WO2019189479A1 - Packaging material and retort pouch or microwavable pouch provided with packaging material - Google Patents

Abstract

This packaging material is provided with a substrate and a sealant layer. The substrate comprises only a single biaxially stretched plastic film containing polyester as a main component. The value resulting from dividing the loop stiffness of the packaging material in one direction by the thickness of the packaging material is 0.00085 (N/µm) or more.

Description

Retort pouch or pouch for microwave oven provided with packaging material and packaging material

The present invention relates to a packaging material and a packaging product such as a retort pouch or a microwave oven pouch provided with the packaging material.

Conventionally, various packaging materials have been developed as packaging materials for composing packaging products such as bags and containers filled with various articles such as food and drink, pharmaceuticals, chemicals, cosmetics, hygiene products, daily necessities, etc. Proposed. The packaging material is composed of a laminate in which at least one stretched plastic film and at least a sealant layer for welding the packaging materials are laminated. For example, Patent Document 1 discloses as a packaging material a stretched polyethylene terephthalate film, a silica-deposited stretched polyethylene terephthalate film, an alumina-deposited stretched polyethylene terephthalate film, a stretched nylon film, a stretched polypropylene film, or a polypropylene / ethylene-vinyl alcohol copolymer co-pushing. It has been proposed to use a stretched film or a composite film in which two or more of these films are laminated.

JP 2015-120550 A

The packaging material for forming the packaged product is required to have rigidity for preventing the packaged product from being broken even when a sharp member having a sharp tip contacts the packaged product.

The present invention has been made in consideration of such points, and an object thereof is to provide a packaging material having rigidity.

One embodiment of the present invention is a packaging material,
A substrate and a sealant layer;
The base material has only one biaxially stretched plastic film containing polyester as a main component,
The packaging material has a value obtained by dividing the loop stiffness in one direction of the packaging material by the thickness of the packaging material of 0.00085 [N / μm] or more.

One embodiment of the present invention is a packaging material,
A substrate and a sealant layer;
The base material has only one biaxially stretched plastic film containing polyester as a main component,
The biaxially stretched plastic film is a packaging material having a loop stiffness of 0.0017 N or more in one direction.

One embodiment of the present invention is a packaging material,
A substrate and a sealant layer;
The substrate has only one biaxially stretched plastic film containing polyethylene terephthalate as a main component,
The packaging material has a puncture strength of 12 N or more.

One embodiment of the present invention is a packaging material,
A substrate and a sealant layer;
The base material has only one biaxially stretched plastic film containing polyester as a main component,
In at least one direction, the packaging material has a value obtained by dividing the tensile strength of the biaxially stretched plastic film by the tensile elongation is 2.0 [MPa /%] or more.

In the packaging material according to one embodiment of the present invention, the biaxially stretched plastic film may contain polyethylene terephthalate as a main component.

In the packaging material according to one embodiment of the present invention, the puncture strength of the packaging material may be 12N or more.

The packaging material according to an embodiment of the present invention may include a printing layer.

The packaging material according to an embodiment of the present invention may include a vapor deposition layer located on the surface of the biaxially stretched plastic film and a gas barrier coating film located on the vapor deposition layer.

In the packaging material according to one embodiment of the present invention, the sealant layer may contain polypropylene as a main component.

In the packaging material according to an embodiment of the present invention, the sealant layer may include polyethylene having a melting point of 100 ° C. or higher.

In the packaging material according to an embodiment of the present invention, the sealant layer includes a first layer mainly composed of polyethylene or polypropylene, and a second layer that is located closer to the inner surface than the first layer and includes a mixed resin of polyethylene and polypropylene. And may have a layer.

One embodiment of the present invention is a retort pouch provided with the packaging material described above.

One embodiment of the present invention is a microwave oven pouch having a storage portion,
Steam-wrapped packaging material;
It is a pouch for microwave ovens provided with the seal part which joins the inner surfaces of the said packaging material, Comprising: The seal | sticker part containing the steam release seal part which peels by the increase in the pressure of the said accommodating part.

According to the present invention, a packaging material having rigidity can be provided.

It is a front view which shows the bag in the 1st Embodiment of this invention. It is sectional drawing which shows an example of the layer structure of the packaging material which comprises a bag. It is sectional drawing which shows the modification of the layer structure of the packaging material which comprises a bag. It is a top view which shows an example of a loop stiffness measuring device. FIG. 5 is a cross-sectional view taken along line VV of the loop stiffness measuring device of FIG. 4. It is a figure which shows an example of the method of preparing the test piece used with a loop stiffness measuring device. It is a figure for demonstrating the process of attaching a test piece to a loop stiffness measuring device. It is a figure for demonstrating the process of forming a loop part in a test piece. It is a figure for demonstrating the process of applying a load to the loop part of a test piece. It is a figure for demonstrating the process of applying a load to the loop part of a test piece. It is a figure which shows an example of the layer structure of a sealant layer. It is a figure which shows an example of the method of filling the contents with a bag. It is a front view which shows one modification of a bag. It is a front view which shows one modification of a bag. It is a longitudinal cross-sectional view which shows an example of the container containing a packaging material. It is a top view which shows an example of the container containing a packaging material. It is sectional drawing which shows an example of the packaging material by 2nd Embodiment. It is sectional drawing which shows an example of the packaging material by 2nd Embodiment. It is sectional drawing which shows an example of the base material of a barriering laminated film. It is a figure which shows an example of the result of having analyzed the vapor deposition layer of the barrier laminated film with the time-of-flight type secondary ion mass spectrometer. It is a figure which shows an example of the film-forming apparatus which forms a vapor deposition layer in a base material. It is a figure which shows an example of the measuring method of piercing strength. It is a top view which shows the test piece for evaluating impact strength. It is sectional drawing of the test piece shown in FIG. It is a figure which shows an example of the measuring method of impact strength. It is a top view which shows the test piece for evaluating tearability. It is a figure which shows the evaluation result of Example A1-A5 and Comparative Example A1-A2. It is a figure which shows the evaluation result of Example A1-A3 and Comparative Example A1-A2. It is a figure which shows the evaluation result of Example C1-C3. It is a figure which shows the evaluation result of Example C1-C3.

First Embodiment An embodiment of the present invention will be described with reference to FIGS. Note that, in the drawings attached to the present specification, for convenience of illustration and understanding, the scale and vertical / horizontal dimension ratios are appropriately changed and exaggerated from those of the actual ones.

In addition, as used in this specification, the shape and geometric conditions and the degree thereof are specified, for example, terms such as “parallel”, “orthogonal”, “identical”, length and angle values, etc. are strictly Without being bound by meaning, it should be interpreted including the extent to which similar functions can be expected.

FIG. 1 is a front view showing a bag 10 according to the present embodiment. The bag 10 includes a storage portion 17 that stores the contents. In addition, in FIG. 1, the bag 10 of the state before the contents are accommodated is shown. Hereinafter, the configuration of the bag 10 will be described.

In the present embodiment, the bag 10 is a gusseted bag configured to be able to stand on its own. The bag 10 includes an upper portion 11, a lower portion 12, and a pair of side portions 13, and has a substantially rectangular outline in a front view. It should be noted that names such as “upper”, “lower” and “side”, and terms such as “upper” and “lower” refer to a bag based on the state in which the bag 10 is self-supporting with the gusset portion down. It is only a relative representation of the position and direction of 10 and its components. The attitude | position at the time of transport of the bag 10 or use is not limited by the name and terminology in this specification.

In the present embodiment, the width direction of the bag 10 is also referred to as a first direction D1. The pair of side portions 13 described above face each other in the first direction D1. A direction orthogonal to the first direction D1 is also referred to as a second direction D2. In the bag 10 of the present embodiment, a usage pattern is assumed in which the consumer opens the bag 10 by tearing the bag 10 along the first direction D1.

As shown in FIG. 1, the bag 10 includes a surface film 14 that constitutes the front surface, a back film 15 that constitutes the back surface, and a lower film 16 that constitutes the lower portion 12. The lower film 16 is disposed between the front film 14 and the back film 15 in a state where the lower film 16 is folded at the folded portion 16f.

In addition, the term “surface film”, “back film” and “lower film” described above is merely a partition of each film according to the positional relationship, and the method of providing a film when manufacturing the bag 10 It is not limited by the above terms. For example, the bag 10 may be manufactured using one film in which the front film 14, the back film 15, and the lower film 16 are continuously provided, or one sheet in which the front film 14 and the lower film 16 are continuously provided. It may be manufactured using a total of two films, a film and one back film 15, and a total of three films, one surface film 14, one back film 15, and one lower film 16. May be used.

The inner surfaces of the front film 14, the back film 15, and the lower film 16 are joined together by a seal portion. In the plan view of the bag 10 shown in FIG. 1 and the like, the seal portion is hatched.

As shown in FIG. 1, the seal portion has an outer edge seal portion that extends along the outer edge of the bag 10. The outer edge seal portion includes a lower seal portion 12 a extending in the lower portion 12 and a pair of side seal portions 13 a extending along the pair of side portions 13. In addition, in the bag 10 in a state before the contents are accommodated, as shown in FIG. 1, the upper portion 11 of the bag 10 is an opening 11b. After the contents are stored in the bag 10, the upper seal portion 11 a (see FIG. 6) is formed by sealing the bag 10 by joining the inner surface of the front film 14 and the inner surface of the back film 15 at the upper portion 11. The

The side seal part 13 a and the upper seal part 11 a are seal parts configured by joining the inner surface of the front film 14 and the inner surface of the back film 15. On the other hand, the lower seal portion 12a is formed by bonding the inner surface of the surface film 14 and the inner surface of the lower film 16, and by bonding the inner surface of the back film 15 and the inner surface of the lower film 16. Including a configured seal.

As long as the opposing films can be joined and the bag 10 can be sealed, the method for forming the seal portion is not particularly limited. For example, the sealing portion may be formed by melting the inner surfaces of the film by heating or the like and welding the inner surfaces, that is, by heat sealing. Or you may form a seal | sticker part by adhere | attaching the inner surfaces of the opposing film using an adhesive agent etc.

Easy opening means The front film 14 and the back film 15 may be provided with easy opening means 25 for tearing the front film 14 and the back film 15 along the first direction D1 to open the bag 10. . For example, as shown in FIG. 1, the easy-opening means 25 may include a notch 26 that is formed in the side seal portion 13 a of the bag 10 and serves as a starting point of tearing. Further, a half-cut line formed by laser processing, a cutter, or the like may be provided as the easy-opening means 25 in a portion that becomes a path when the bag 10 is torn.

Although not shown, the easy-opening means 25 may include notches and scars formed in the area where the seal portion is formed in the front film 14 and the back film 15. The scar group may include, for example, a plurality of through holes formed so as to penetrate the front film 14 and / or the back film 15. Alternatively, the scar group may include a plurality of holes formed on the outer surface of the front film 14 and / or the back film 15 so as not to penetrate the front film 14 and / or the back film 15.

Next, the layer structure of the front film 14 and the back film 15 will be described. FIG. 2 is a cross-sectional view showing an example of the layer structure of the packaging material 30 that constitutes the front film 14 and the back film 15.

As shown in FIG. 2, the packaging material 30 includes a base material 35 and a sealant layer 70 joined to the base material 35 by an adhesive layer 65. The base material 35 has only one stretched plastic film as indicated by reference numeral 60. The stretched plastic film 60 is located on the outer surface 30y side, and the sealant layer 70 is located on the inner surface 30x side opposite to the outer surface 30y. The inner surface 30x is a surface located on the accommodating portion 17 side.

Each film constituting the packaging material 30 such as the stretched plastic film 60 and the sealant film for constituting the sealant layer 70, and the packaging material 30 have a flow direction and a vertical direction. The flow direction is a direction in which the film flows when the film is formed, and is so-called MD (Machine-Direction). The vertical direction is a direction orthogonal to the flow direction and is a so-called TD (Transverse Direction). In the bag 10 shown in FIG. 1, the direction in which the upper part 11 and the lower part 12 extend is the flow direction, and the direction in which the side part 13 extends is the vertical direction.

The packaging material 30 of the present embodiment is configured to have rigidity. Thereby, the bag 10 including the packaging material 30 can be given rigidity. For example, it is possible to prevent the bag 10 from being broken when a sharp member with a sharp tip contacts the bag 10. The thickness of the packaging material 30 is, for example, 60 μm or more, 70 μm or more, 80 μm or more, or 90 μm or more. The thickness of the packaging material 30 may be 120 μm or less, 110 μm or less, or 100 μm or less.

Hereinafter, each layer of the packaging material 30 will be described in detail.

(Stretched plastic film)
The stretched plastic film 60 is a biaxially stretched plastic film that is stretched in two predetermined directions. The stretching direction of the stretched plastic film 60 is not particularly limited. For example, the stretched plastic film 60 may be stretched in the direction in which the side portion 13 extends, or may be stretched in a direction orthogonal to the direction in which the side portion 13 extends. Moreover, the extending | stretching directions of the stretched plastic film 60 may mutually be the same, and may differ. The stretch ratio of the stretched plastic film 60 is, for example, 1.05 times or more.

In the present embodiment, as the stretched plastic film 60, it is proposed to use a stretched plastic film having a loop stiffness of 0.0017N or more in at least one direction and containing polyester as a main component. In the following description, a stretched plastic film having a loop stiffness of 0.0017 N or more in at least one direction and containing polyester as a main component is also referred to as a high stiffness polyester film. The high stiffness polyester film has a loop stiffness of 0.0017 N or more in at least one of the flow direction (MD) and the vertical direction (TD), for example. The high stiffness polyester film may have, for example, a loop stiffness of 0.0017 N or more in both the flow direction (MD) and the vertical direction (TD). When the packaging material 30 includes the high stiffness polyester film, the packaging material 30 can have rigidity.
The polyester is at least one aromatic dicarboxylic acid selected from terephthalic acid, isophthalic acid and 2,6-naphthalenedicarboxylic acid, and at least selected from ethylene glycol, 1,3-propanediol and 1,4-butanediol. A polyester mainly composed of an aromatic polyester composed of one kind of aliphatic alcohol is preferred. For example, the polyester includes polyethylene terephthalate (hereinafter also referred to as PET), polybutylene terephthalate (hereinafter also referred to as PBT), and the like. High Stiffness Polyester Film Examples of the high stiffness polyester film include a high stiffness PET film containing 51% by mass or more of PET as a main component, and a high stiffness PBT film containing 51% by mass or more of PBT as a main component. . The thickness of the high stiffness polyester film is preferably 5 μm or more, more preferably 7 μm or more. Further, the thickness of the high stiffness polyester film is preferably 25 μm or less, more preferably 20 μm or less.

Loop stiffness is a parameter representing the strength of a film such as a stretched plastic film. Hereinafter, a method for measuring the loop stiffness will be described with reference to FIGS. Note that the measurement method described below can be used not only for a single layer film such as a stretched plastic film but also for a plurality of layers such as a vapor deposition film and a laminated film. The vapor deposition film is a film including a single layer film such as a stretched plastic film and a vapor deposition layer formed on the single layer film. The laminated film is a film including a plurality of laminated films such as the packaging material 30.

4 is a plan view showing the test piece 80 and the loop stiffness measuring device 85, and FIG. 5 is a cross-sectional view of the test piece 80 and the loop stiffness measuring device 85 in FIG. 4 along the line V-V. The test piece 80 is a rectangular film having a long side and a short side. In the present application, the long side length L1 of the test piece 80 is 150 mm, and the short side length L2 is 15 mm. As the loop stiffness measuring instrument 85, for example, No. manufactured by Toyo Seiki Co., Ltd. 581 Loop Stiffness Tester (registered trademark) LOOP STIFFNESS TESTER DA type can be used. The long side length L1 of the test piece 80 can be adjusted as long as the test piece 80 can be gripped by a pair of chuck portions 86 described later.

The loop stiffness measuring instrument 85 includes a pair of chuck portions 86 for gripping a pair of end portions in the long side direction of the test piece 80, and a support member 87 for supporting the chuck portions 86. The chuck portion 86 includes a first chuck 861 and a second chuck 862. 4 and 5, the test piece 80 is disposed on the pair of first chucks 861, and the second chuck 862 still holds the test piece 80 with the first chuck 861. Not. As will be described later, at the time of measurement, the test piece 80 is held between the first chuck 861 and the second chuck 862 of the chuck portion 86. The second chuck 862 may be connected to the first chuck 861 via a hinge mechanism.

When a film to be measured such as a stretched plastic film, a vapor-deposited film, and a laminated film is available in a state before the film is processed into a packaged product, the test piece 80 is produced by cutting the film to be measured. May be. Moreover, the test piece 80 may be produced by cutting a packaged product produced from the packaging material 30 such as a bag and taking out a film to be measured. FIG. 6 is a diagram illustrating an example of a method for preparing the test piece 80 by cutting the front film 14 or the back film 15 of the bag 10. When measuring the loop stiffness of the packaging material 30 in the flow direction, the front film 14 or the back film 15 of the bag 10 is cut so that the long side direction of the test piece coincides with the flow direction as indicated by reference numeral 80A in FIG. To prepare a test piece. When measuring the loop stiffness of the packaging material 30 in the vertical direction, the front film 14 or the back film 15 of the bag 10 is cut so that the long side direction of the test piece coincides with the vertical direction as indicated by reference numeral 80B in FIG. To prepare a test piece.

A method for measuring the loop stiffness of the test piece 80 using the loop stiffness measuring device 85 will be described. First, as shown in FIGS. 4 and 5, the test piece 80 is placed on the first chuck 861 of the pair of chuck portions 86 arranged with a gap L3. In the present application, the interval L3 is set so that the length of the loop portion 81 (to be described later) (hereinafter also referred to as loop length) is 60 mm. The test piece 80 includes an inner surface 80x located on the first chuck 861 side and an outer surface 80y located on the opposite side of the inner surface 80x. When the test piece 80 is made of the packaging material 30, the inner surface 80x and the outer surface 80y of the test piece 80 coincide with the inner surface 30x and the outer surface 30y of the packaging material 30. When the loop portion 81 described later is formed on the test piece 80, the inner surface 80 x is positioned inside the loop portion 81 and the outer surface 80 y is positioned outside the loop portion 81. Subsequently, as shown in FIG. 7, the second chuck 862 is disposed on the test piece 80 so as to grip the end portion of the test piece 80 in the long side direction with the first chuck 861.

Subsequently, as shown in FIG. 8, at least one of the pair of chuck portions 86 is slid on the support member 87 in a direction in which the distance between the pair of chuck portions 86 is reduced. Thereby, the loop part 81 can be formed in the test piece 80. A test piece 80 shown in FIG. 8 includes a loop portion 81, a pair of intermediate portions 82, and a pair of fixing portions 83. The pair of fixing portions 83 are portions of the test piece 80 that are gripped by the pair of chuck portions 86. The pair of intermediate portions 82 are portions of the test piece 80 that are located between the loop portion 81 and the pair of intermediate portions 82. As shown in FIG. 7, the chuck portion 86 is slid on the support member 87 until the inner surfaces 80x of the pair of intermediate portions 82 come into contact with each other. Thereby, the loop part 81 which has a loop length of 60 mm can be formed. The loop length of the loop portion 81 is such that the position P1 where the surface on the loop portion 81 side of one second chuck 862 and the test piece 80 intersect, the surface on the loop portion 81 side of the other second chuck 862, and the test piece 80 This is the length of the test piece 80 between the position P2 and the position P2. The interval L3 is a value obtained by adding 2 × t to the length of the loop portion 81 when the thickness of the test piece 80 is ignored. t is the thickness of the second chuck 862 of the chuck portion 86.

Thereafter, as shown in FIG. 9, the posture of the chuck portion 86 is adjusted so that the protruding direction Y of the loop portion 81 with respect to the chuck portion 86 is horizontal. For example, the posture of the chuck portion 86 supported by the support member 87 is adjusted by moving the support member 87 so that the normal direction of the support member 87 faces the horizontal direction. In the example shown in FIG. 9, the protruding direction Y of the loop portion 81 coincides with the thickness direction of the chuck portion. In addition, the load cell 88 is prepared at a position away from the second chuck 862 by the distance Z1 in the projecting direction Y of the loop portion 81. In the present application, the distance Z1 is 50 mm. Subsequently, the load cell 88 is moved toward the loop portion 81 of the test piece 80 at a speed V by a distance Z2 shown in FIG. As shown in FIGS. 9 and 10, the distance Z2 is set so that the load cell 88 comes into contact with the loop portion 81 and then the load cell 88 pushes the loop portion 81 toward the chuck portion 86. In the present application, the distance Z2 is 40 mm. In this case, the distance Z3 between the load cell 88 and the second chuck 862 of the chuck portion 86 in a state where the load cell 88 pushes the loop portion 81 toward the chuck portion 86 is 10 mm. The speed V for moving the load cell 88 was 3.3 mm / second.

Subsequently, the load cell 88 shown in FIG. 10 is moved to the chuck portion 86 side by a distance Z2, and the load cell 88 is added to the load cell 88 from the loop portion 81 in a state where the load cell 88 pushes the loop portion 81 of the test piece 80. After the load value stabilizes, record the load value. The load value thus obtained is adopted as the loop stiffness of the film constituting the test piece 80. In this application, unless otherwise specified, the environment at the time of measuring loop stiffness is a temperature of 23 ° C. and a relative humidity of 50%.

The preferred mechanical properties of the high stiffness polyester film will be further described.
The puncture strength of the high stiffness polyester film is preferably 10N or more, more preferably 11N or more.

The tensile strength of the high stiffness polyester film in at least one direction is preferably 250 MPa or more, more preferably 280 MPa or more. For example, the tensile strength of the high stiffness polyester film in the flow direction is preferably 250 MPa or more, more preferably 280 MPa or more. Further, the tensile strength of the high stiffness polyester film in the vertical direction is preferably 250 MPa or more, more preferably 280 MPa or more.
The tensile elongation of the high stiffness polyester film in at least one direction is preferably 130% or less, more preferably 120% or less. For example, the tensile elongation of the high stiffness polyester film in the flow direction is preferably 130% or less, more preferably 120% or less. Further, the tensile elongation of the high stiffness polyester film in the vertical direction is preferably 120% or less, and more preferably 110% or less.
Preferably, in at least one direction, a value obtained by dividing the tensile strength of the high stiffness polyester film by the tensile elongation is 2.0 [MPa /%] or more. For example, the value obtained by dividing the tensile strength of the high stiffness polyester film in the vertical direction (TD) by the tensile elongation is preferably 2.0 [MPa /%] or more, more preferably 2.2 [MPa /%]. That's it. The value obtained by dividing the tensile strength of the high stiffness polyester film in the flow direction (MD) by the tensile elongation is preferably 1.8 [MPa /%] or more, more preferably 2.0 [MPa /%] or more. is there.
The tensile strength and tensile elongation can be measured according to JIS K7127. As a measuring instrument, a tensile tester STA-1150 manufactured by Orientec Corporation can be used. As the test piece, a high-stiffness polyester film cut into a rectangular film having a width of 15 mm and a length of 150 mm can be used. The distance at the start of measurement between the pair of chucks holding the test piece is 100 mm, and the tensile speed is 300 mm / min. In this application, unless otherwise specified, the environment at the time of measurement of tensile strength and tensile elongation is a temperature of 23 ° C. and a relative humidity of 50%.
In the bag 10 shown in FIG. 1, the first direction D <b> 1 corresponds to the flow direction (MD) of a film such as the stretched plastic film 60. The second direction D2 corresponds to the vertical direction (TD) of a film such as the stretched plastic film 60.

The heat shrinkage ratio of the high stiffness polyester film in at least one direction is preferably 0.7% or less, and more preferably 0.5% or less. For example, the thermal contraction rate of the high stiffness polyester film in the flow direction is preferably 0.7% or less, and more preferably 0.5% or less. The heat shrinkage rate of the high stiffness polyester film in the vertical direction is preferably 0.7% or less, and more preferably 0.5% or less. The heating temperature when measuring the heat shrinkage rate is 100 ° C., and the heating time is 40 minutes.
The tensile elasticity modulus of the high stiffness polyester film in at least one direction is preferably 4.0 GPa or more, more preferably 4.5 MPa or more. For example, the tensile elastic modulus of the high stiffness polyester film in the flow direction is preferably 4.0 GPa or more, more preferably 4.5 MPa or more. The tensile elastic modulus of the high stiffness polyester film in the vertical direction is preferably 4.0 GPa or more, more preferably 4.5 GPa or more.

In the production process of a high stiffness polyester film, for example, a plastic film obtained by melting and molding polyester is first subjected to 3 times to 4.5 times at 90 to 145 ° C. in the flow direction and the vertical direction, respectively. The 1st extending process extended | stretched is implemented. Subsequently, a second stretching step is performed in which the plastic film is stretched 1.1 to 3.0 times at 100 to 145 ° C. in the flow direction and the vertical direction, respectively. Thereafter, heat setting is performed at a temperature of 190 ° C. to 220 ° C. Subsequently, in the flow direction and the vertical direction, a relaxation treatment (treatment for reducing the film width) of about 0.2% to 2.5% is performed at a temperature of 100 ° C. to 190 ° C. In these steps, a high stiffness polyester film having the above-mentioned mechanical properties can be obtained by adjusting the stretching ratio, stretching temperature, heat setting temperature, and relaxation treatment rate.

According to the present embodiment, the packaging material 30 includes the high stiffness polyester film, whereby the strength of the packaging material 30 can be increased. For example, the loop stiffness of the packaging material 30 per unit thickness of the packaging material 30 can be increased. The value obtained by dividing the loop stiffness of the packaging material 30 in at least one direction by the thickness of the packaging material 30 is, for example, 0.00085 N / μm or more, may be 0.00090 N / μm or more, and 0.00095 N / μm. The above may be sufficient, and 0.00100 N / micrometer or more may be sufficient. For example, the value obtained by dividing the loop stiffness of the packaging material 30 in the flow direction (MD) by the thickness of the packaging material 30 is, for example, 0.00085 N / μm or more, and may be 0.00090 N / μm or more. It may be greater than or equal to 00095 N / μm and may be greater than or equal to 0.00100 N / μm. The value obtained by dividing the loop stiffness of the packaging material 30 in the vertical direction (TD) by the thickness of the packaging material 30 is, for example, 0.00080 N / μm or more, and may be 0.00085 N / μm or more. It may be 9090 N / μm or more, or 0.00095 N / μm or more.

When the high stiffness polyester film is a high stiffness PET film containing PET as a main component, the PET constituting the high stiffness PET film may contain biomass-derived PET. In this case, the high stiffness PET film may be composed of only biomass-derived PET. Alternatively, the high stiffness PET film may be composed of biomass-derived PET and fossil fuel-derived PET. Since the high-stiffness PET film contains biomass-derived PET, the amount of PET derived from fossil fuel can be reduced compared to the conventional case, so that the amount of carbon dioxide emission can be reduced and the environmental load can be reduced. it can. Biomass-derived PET uses biomass-derived ethylene glycol as a diol unit and fossil fuel-derived terephthalic acid as a dicarboxylic acid unit. Fossil fuel-derived PET uses fossil fuel-derived ethylene glycol as diol units and fossil fuel-derived terephthalic acid as dicarboxylic acid units.

Since carbon dioxide in the atmosphere contains C14 at a constant ratio (105.5 pMC), the C14 content in plants that take in carbon dioxide in the atmosphere and grow, for example, corn, is also about 105.5 pMC. It is known. It is also known that fossil fuel contains almost no C14. Therefore, the ratio of carbon derived from biomass can be calculated by measuring the ratio of C14 contained in all carbon atoms in PET. In the present invention, “biomass degree” indicates the weight ratio of biomass-derived components. Taking PET as an example, PET is obtained by polymerizing ethylene glycol containing 2 carbon atoms and terephthalic acid containing 8 carbon atoms in a molar ratio of 1: 1. When only biomass-derived components are used as the ethylene glycol of PET, the weight ratio of biomass-derived components in PET is 31.25%, so the theoretical value of the biomass degree of PET is 31.25%. Specifically, since the mass of PET is 192 and the mass derived from biomass-derived ethylene glycol is 60, 60 ÷ 192 × 100 = 31.25. Moreover, the weight ratio of the biomass-derived component in PET derived from fossil fuel is 0%, and the biomass degree of PET derived from fossil fuel is 0%. In the present invention, the biomass degree of the high stiffness PET film is preferably 5.0% or more, and more preferably 10.0% or more. The biomass degree of the high stiffness PET film is preferably 30.0% or less.

Biomass-derived ethylene glycol is made from ethanol (biomass ethanol) produced from biomass as a raw material. For example, biomass-derived ethylene glycol can be obtained from biomass ethanol by a conventionally known method, such as a method of producing ethylene glycol via ethylene oxide. Examples of raw materials for biomass ethanol include corn, sugar cane, beet, and manioc. Moreover, you may use commercially available biomass ethylene glycol, for example, the biomass ethylene glycol marketed from India Glycol can be used conveniently. India Glycoal's biomass ethylene glycol is made from sugarcane waste molasses.

(Adhesive layer)
The adhesive layer 65 includes an adhesive for bonding the stretched plastic film 60 and the sealant layer 70 by a dry laminating method. The adhesive constituting the adhesive layer 65 is generated from an adhesive composition prepared by mixing a first composition containing a main agent and a solvent and a second composition containing a curing agent and a solvent. Specifically, an adhesive contains the hardened | cured material produced | generated by the reaction of the main ingredient and solvent in an adhesive composition.

Examples of adhesives include polyurethane. Polyurethane is a cured product produced by a reaction between a polyol as a main agent and an isocyanate compound as a curing agent. Examples of polyurethane include polyether polyurethane and polyester polyurethane. The polyether polyurethane is a cured product produced by a reaction between a polyether polyol as a main agent and an isocyanate compound as a curing agent. Polyester polyurethane is a cured product produced by a reaction between a polyester polyol as a main agent and an isocyanate compound as a curing agent.

Isocyanate compounds include aromatic isocyanate compounds such as tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and the like. Aliphatic isocyanate compounds, or adducts or multimers of the above-mentioned various isocyanate compounds can be used.

As described above, an aromatic isocyanate compound and an aliphatic isocyanate compound exist as the isocyanate compound constituting the curing agent of the adhesive. Among these, aromatic isocyanate compounds elute components that cannot be used in food applications under high-temperature environments such as heat sterilization. Incidentally, the adhesive layer 65 is in contact with the sealant layer 70. For this reason, when the adhesive layer 65 contains an aromatic isocyanate compound, the component eluted from the aromatic isocyanate compound may adhere to the contents accommodated in the accommodating portion 17 in contact with the sealant layer 70. .

In consideration of such problems, preferably, a cured product produced by a reaction between a polyol as a main agent and an aliphatic isocyanate compound as a curing agent is used as an adhesive constituting the adhesive layer 65. . Thereby, the component which cannot be used for the food use resulting from the adhesive bond layer 65 can prevent adhering to the content.

The material constituting the adhesive layer 65 preferably has a higher thermal conductivity than the material constituting the stretched plastic film 60. For example, the thermal conductivity of the material constituting the adhesive layer 65 is preferably 1.0 W / m · K or more, more preferably 3.0 W / m · K or more. The thermal conductivity of polyurethane is in the range of 3.0 W / m · K to 5.0 W / m · K, for example 5.0 W / m · K. Due to the high thermal conductivity of the material constituting the adhesive layer 65, when the bag 10 made using the packaging material 30 is heated, the heat generated in the housing portion 17 is generated from the inner surface 30x side of the packaging material 30. Heat is easily diffused in the surface direction of the packaging material 30 while being transferred to the outer surface 30y side. Thereby, since the heat dissipation of the packaging material 30 can be improved, the temperature rise of the packaging material 30 can be suppressed. As a result, the packaging material 30 can be prevented from being damaged by heat when the bag 10 is heated. That is, the heat resistance of the packaging material 30 can be increased.

The thickness of the adhesive layer 65 is preferably 2 μm or more, more preferably 3 μm or more. The thickness of the adhesive layer 65 is preferably 6 μm or less, and more preferably 5 μm or less. By setting the thickness of the adhesive layer 65 to 3 μm or more, heat diffusion in the surface direction of the packaging material 30 is more likely to occur.

(Sealant layer)
Next, the sealant layer 70 will be described. As a material constituting the sealant layer 70, one or more resins selected from polyethylene such as low density polyethylene and linear low density polyethylene, and polypropylene can be used. The sealant layer 70 may be a single layer or a multilayer. The sealant layer 70 is preferably made of an unstretched sealant film. “Unstretched” is a concept that includes not only a film that is not stretched at all, but also a film that is slightly stretched due to the tension applied during film formation.

The sealant film that constitutes the sealant layer 70 is, for example, a plastic film that has been subjected to a stretching process necessary for conveyance, but has not been intentionally stretched. The preferred mechanical properties of the sealant film will be further described.
The tensile elastic modulus of the sealant film in at least one direction is preferably 1000 MPa or less. For example, the tensile elastic modulus of the sealant film in the flow direction and the vertical direction is preferably 1000 MPa or less.
The tensile elongation of the sealant film in at least one direction is preferably 300% or more. For example, the tensile elongation of the sealant film in the flow direction and the vertical direction is preferably 300% or more.

The tensile elastic modulus and tensile elongation of the sealant film can be measured according to JIS K7127, as in the case of the high stiffness polyester film. As a measuring instrument, a tensile tester STA-1150 manufactured by Orientec Corporation can be used. As the test piece, a film obtained by cutting the film into a rectangular film having a width of 15 mm and a length of 150 mm can be used. The distance at the start of measurement between the pair of chucks holding the test piece is 100 mm, and the tensile speed is 300 mm / min.

The bag 10 composed of the packaging material 30 may be subjected to a sterilization process such as a boil process or a retort process at a high temperature. The sealant layer 70 is preferably heat resistant to withstand these high temperature processes. The retort process is a process of filling the bag 10 with the contents and sealing the bag 10 and then heating the bag 10 in a pressurized state using steam or heated hot water.
The temperature of retort processing is 120 degreeC or more, for example. The boil process is a process of filling the bag 10 with the contents and sealing the bag 10 and then bathing the bag 10 under atmospheric pressure. The temperature of boil processing is 90 degreeC or more and 100 degrees C or less, for example.

The melting point of the material constituting the sealant layer 70 is preferably 150 ° C. or higher, and more preferably 160 ° C. or higher. By increasing the melting point of the sealant layer 70, the bag 10 can be retorted at a high temperature, and therefore the time required for the retort processing can be shortened. The melting point of the material constituting the sealant layer 70 is lower than the melting point of the resin constituting the stretched plastic film 60.

When considering from the viewpoint of retort treatment, a material mainly composed of propylene can be used as a material constituting the sealant layer 70. Here, the material having “propylene as a main component” means a material having a propylene content of 90% by mass or more. Specific examples of the material mainly composed of propylene include propylene / ethylene block copolymer, propylene / ethylene random copolymer, polypropylene such as homopolypropylene, or a mixture of polypropylene and polyethylene. Can do. Here, the “propylene / ethylene block copolymer” means a material having a structural formula represented by the following formula (I). The “propylene / ethylene random copolymer” means a material having a structural formula represented by the following formula (II). “Homopolypropylene” means a material having the structural formula shown by the following formula (III).

In the case of using a mixture of polypropylene and polyethylene as a material mainly composed of propylene, the material may have a sea-island structure. Here, the “sea-island structure” means a structure in which polyethylene is discontinuously dispersed in a region where polypropylene is continuous.

When considered from the viewpoint of boil treatment, examples of the material constituting the sealant layer 70 include polyethylene, polypropylene, or a combination thereof. Examples of polyethylene include medium density polyethylene, linear low density polyethylene, and combinations thereof. For example, it is also possible to use the materials mentioned as the material constituting the sealant layer 70 from the viewpoint of the above retort processing. The material constituting the sealant layer 70 has a melting point of, for example, 100 ° C. or higher, more preferably 105 ° C. or higher, more preferably 110 ° C. or higher, and still more preferably 115 ° C. or higher. When polyethylene is used as the material constituting the sealant layer 70, a melting point of 100 ° C. or higher can be realized, for example, when the density of polyethylene is 0.920 g / cm ³ or higher. Specific examples of the sealant layer for constituting the sealant layer 70 having a melting point of 100 ° C. or higher include TUX-HC manufactured by Mitsui Chemicals Tosero, L6101 manufactured by Toyobo, and LS700C manufactured by Idemitsu Unitech. As a specific example of the sealant layer for constituting the sealant layer 70 having a melting point of 105 ° C. or higher, NB-1 manufactured by Tamapoli can be cited. Specific examples of the sealant layer for forming the sealant layer 70 having a melting point of 110 ° C. or higher include LS760C manufactured by Idemitsu Unitech, TUX-HZ manufactured by Mitsui Chemicals Tosero, and the like.

Preferably, the sealant layer 70 is a single layer film containing a propylene / ethylene block copolymer. For example, the sealant layer including the sealant layer 70 is a single-layer unstretched film whose main component is a propylene / ethylene block copolymer.
By using the propylene / ethylene block copolymer, the impact resistance of the sealant layer can be increased, and thereby, the bag 10 can be prevented from being broken due to the impact at the time of dropping. Moreover, the puncture resistance of the packaging material 30 can be improved.

The propylene / ethylene block copolymer includes, for example, a sea component composed of polypropylene and an island component composed of an ethylene / propylene copolymer rubber component. The sea component can contribute to enhancing the blocking resistance, heat resistance, rigidity, seal strength and the like of the propylene / ethylene block copolymer. In addition, the island component can contribute to enhancing the impact resistance of the propylene / ethylene block copolymer. Therefore, the mechanical properties of the sealant layer containing the propylene / ethylene block copolymer can be adjusted by adjusting the ratio of the sea component and the island component.

In the propylene / ethylene block copolymer, the mass ratio of the sea component made of polypropylene is higher than the mass ratio of the island component made of the ethylene / propylene copolymer rubber component. For example, in the propylene / ethylene block copolymer, the mass ratio of the sea component made of polypropylene is at least 51% by mass, preferably 60% by mass or more, and more preferably 70% by mass or more.

The single-layer sealant layer may further contain a second thermoplastic resin in addition to the first thermoplastic resin made of propylene / ethylene block copolymer. Examples of the second thermoplastic resin include an α-olefin copolymer and polyethylene. The α-olefin copolymer is, for example, linear low density polyethylene. Examples of polyethylene include low density polyethylene, medium density polyethylene, and high density polyethylene. The second thermoplastic resin can contribute to increasing the impact resistance of the sealant layer.

The low-density polyethylene, density of 0.910 g / cm ³ or more and 0.925 g / cm ³ or less of polyethylene. Medium density polyethylene is polyethylene having a density of 0.926 g / cm ³ or more and 0.940 g / cm ³ or less. The high density polyethylene is polyethylene having a density of 0.941 g / cm ³ or more and 0.965 g / cm ³ or less. Low density polyethylene is obtained, for example, by polymerizing ethylene at a high pressure of 1000 atm or more and less than 2000 atm. The medium density polyethylene and the high density polyethylene are obtained, for example, by polymerizing ethylene at a medium pressure or low pressure of 1 atm or more and less than 1000 atm.

The medium density polyethylene and the high density polyethylene may partially contain a copolymer of ethylene and α-olefin. Even when ethylene is polymerized at an intermediate pressure or a low pressure, when a copolymer of ethylene and an α-olefin is contained, an intermediate density or low density polyethylene can be produced. Such polyethylene is referred to as the above-mentioned linear low density polyethylene. The linear low density polyethylene is obtained by introducing a short chain branch by copolymerizing an α-olefin with a linear polymer obtained by polymerizing ethylene at a medium pressure or a low pressure. Examples of α-olefins include 1-butene (C ₄ ), 1-hexene (C ₆ ), 4-methylpentene (C ₆ ), 1-octene (C ₈ ) and the like. The density of the linear low density polyethylene is, for example, 0.915 g / cm ³ or more and 0.945 g / cm ³ or less.

Note that the α-olefin copolymer constituting the second thermoplastic resin of the propylene / ethylene block copolymer is not limited to the above-mentioned linear low density polyethylene. The α-olefin copolymer means a material having a structural formula represented by the following formula (IV).

　Ｒ_１、Ｒ_２はいずれも、Ｈ（水素原子）、又はＣＨ_３、Ｃ_２Ｈ_５などのアルキル基である。また、ｊ及びｋはいずれも、１以上の整数である。また、ｊはｋよりも大きい。すなわち、式（IV）に示すα－オレフィン共重合体においては、Ｒ_１を含む左側の構造がベースとなる。Ｒ_１は例えばＨであり、Ｒ_２は例えばＣ_２Ｈ_５である。

R ₁ and R ₂ are both H (hydrogen atom) or an alkyl group such as CH ₃ or C ₂ H ₅ . J and k are both integers of 1 or more. J is larger than k. That is, in the α-olefin copolymer represented by the formula (IV), the left side structure including R ₁ is the base. R ₁ is, for example, H, and R ₂ is, for example, C ₂ H ₅ .

In the sealant layer, the mass ratio of the first thermoplastic resin made of propylene / ethylene block copolymer is higher than the mass ratio of the second thermoplastic resin containing at least the α-olefin copolymer or polyethylene. For example, in the single-layer sealant layer, the mass ratio of the first thermoplastic resin composed of the propylene / ethylene block copolymer is at least 51% by mass, preferably 60% by mass or more, and more preferably 70%. It is at least mass%.

As described above, the second thermoplastic resin can contribute to enhancing the impact resistance of the sealant layer. Therefore, the mechanical properties of the sealant layer can be adjusted by adjusting the mass ratio of the second thermoplastic resin containing at least the α-olefin copolymer or polyethylene in the single sealant layer.

The sealant layer 70 may further contain a thermoplastic elastomer. By using a thermoplastic elastomer, the impact resistance and puncture resistance of the sealant layer 70 can be further enhanced.

The thermoplastic elastomer is, for example, a hydrogenated styrene thermoplastic elastomer. The hydrogenated styrene-based thermoplastic elastomer has a structure comprising a polymer block A mainly composed of at least one vinyl aromatic compound and a polymer block B mainly composed of at least one hydrogenated conjugated diene compound. . The thermoplastic elastomer may be an ethylene / α-olefin elastomer. The ethylene / α-olefin elastomer is a low crystalline or amorphous copolymer elastomer, which is a random copolymer of 50 to 90% by mass of ethylene as a main component and α-olefin as a comonomer. is there.

Further, the sealant layer 70 may further contain a crystal accelerator. By using a crystal accelerator, the tensile elastic modulus of the sealant layer 70 can be increased. Thereby, the tearability of the sealant layer 70 and the packaging material 30 can be improved. The crystal accelerator is, for example, a phosphoric acid ester metal salt or a benzoic acid metal salt.

The content of the propylene / ethylene block copolymer in the sealant layer 70 is, for example, 80% by mass or more, and preferably 90% by mass or more.

Examples of the method for producing a propylene / ethylene block copolymer include a method of polymerizing propylene, ethylene, and the like as raw materials using a catalyst. As the catalyst, Ziegler-Natta type or metallocene catalyst can be used.

The thickness of the sealant layer 70 is preferably 30 μm or more, more preferably 40 μm or more. Moreover, the thickness of the sealant layer 70 is preferably 100 μm or less, and more preferably 80 μm or less.

Hereinafter, preferable mechanical properties of the sealant film when the sealant layer 70 is formed of a single-layer sealant film containing a propylene / ethylene block copolymer will be described.
The tensile elongation at 25 ° C. of the sealant film in the flow direction (MD) is preferably 600% or more and 1300% or less. The product of the tensile elongation (%) of the sealant film and the thickness (μm) of the sealant film in the flow direction (MD) is preferably 35000 or more and 80000 or less. Further, the tensile elongation at 25 ° C. of the sealant film in the vertical direction (TD) is preferably 700% or more and 1400% or less. The product of the tensile elongation (%) of the sealant film and the thickness (μm) of the sealant film in the vertical direction (TD) is preferably 40000 or more and 85000 or less.
The tensile modulus at 25 ° C. of the sealant film in the flow direction (MD) is preferably 400 MPa or more and 1100 MPa or less. The product of the tensile modulus (MPa) of the sealant film and the thickness (μm) of the sealant film in the flow direction (MD) is preferably 30000 or more and 55000 or less. Further, the tensile elastic modulus at 25 ° C. of the sealant film in the vertical direction (TD) is preferably 250 MPa or more and 900 MPa or less. The product of the tensile modulus (MPa) of the sealant film and the thickness (μm) of the sealant film in the vertical direction (TD) is preferably 20000 or more and 45000 or more.
In the bag 10 shown in FIG. 1, the first direction D1 corresponds to the flow direction (MD) of the sealant film. The second direction D2 corresponds to the vertical direction (TD) of the sealant film.

Tensile modulus and tensile elongation can be measured according to JIS K7127. As a measuring instrument, a tensile tester STA-1150 manufactured by Orientec Corporation can be used. In the bag 10 shown in FIG. 1, the direction in which the upper portion 11 and the lower portion 12 extend is the flow direction of the film constituting the bag 10 such as a sealant film, and the direction in which the side portion 13 extends is such as a sealant film. , The vertical direction of the film constituting the bag 10. Although not shown, the bag 10 may be configured such that the direction in which the upper portion 11 and the lower portion 12 extend is the vertical direction of the film, and the direction in which the side portion 13 extends is the flow direction of the film.

There are mainly two types of single-layer sealant films containing a propylene / ethylene block copolymer.
The first is a type having high tensile elongation and impact resistance, such as an unstretched polypropylene film ZK500 manufactured by Toray Film Processing Co., Ltd. The first type of sealant film preferably further has the property of low hot seal strength. Thereby, it can suppress that the internal pressure of the accommodating part 17 becomes excessive at the time of the heating of the bag 10, and it can suppress that the packaging material 30 arises a damage.
The second is a type having a high tensile elastic modulus, such as unstretched polypropylene film ZK207 or ZK500R manufactured by Toray Film Processing Co., Ltd. By using the second type sealant film, it is possible to improve the tearability when the bag is opened by the consumer tearing the bag 10 along the first direction D1.

The product of the tensile elongation (%) of the first type sealant film in the flow direction (MD) and the thickness (μm) of the sealant film is preferably 45000 or more, more preferably 50000 or more, 55000 or more, Or 60000 or more may be sufficient. The product of the tensile elongation (%) of the first type sealant film and the thickness (μm) of the sealant film in the vertical direction (TD) is preferably 53,000 or more, more preferably 60000 or more. Since the sealant film has a high tensile elongation, the bag 10 can be prevented from breaking due to an impact at the time of dropping or the like.
Further, the product of the tensile modulus (MPa) of the first type sealant film and the thickness (μm) of the sealant film in the flow direction (MD) is preferably 38000 or less, more preferably 35000 or less. The product of the tensile modulus (MPa) of the first type sealant film and the thickness (μm) of the sealant film in the vertical direction (TD) is preferably 30000 or less, more preferably 25000 or less.

The product of the tensile modulus (MPa) of the second type sealant film and the thickness (μm) of the sealant film in the flow direction (MD) is preferably 35000 or more, 38000 or more, 42000 or more, 45000 or more, or 48000. It may be the above. From the viewpoint of tearability, in particular, when the thickness of the single sealant layer 70 is 50 μm, the propylene / ethylene block copolymer has a tensile elastic modulus (MPa) in the flow direction (MD) of 800 MPa or more. It is preferable to use a material containing
The product of the tensile modulus (MPa) of the second type sealant film and the thickness (μm) of the sealant film in the vertical direction (TD) is preferably 25000 or more, 30000 or more, 35000 or more, or 38000 or more. It may be. From the viewpoint of tearability, in particular, when the thickness of the single sealant layer 70 is 50 μm, the propylene / ethylene block copolymer has a tensile elastic modulus (MPa) in the vertical direction (TD) of 650 MPa or more. It is preferable to use a material containing
When the sealant film has a high tensile elastic modulus, the tearability when the bag 10 is opened can be improved.
The product of the tensile elongation (%) of the second type sealant film and the thickness (μm) of the sealant film in the flow direction (MD) is preferably 55000 or less, more preferably 50000 or less. The product of the tensile elongation (%) of the second type sealant film and the thickness (μm) of the sealant film in the vertical direction (TD) is preferably 60000 or less, more preferably 55000 or less.

The sealant layer 70 may have an easy peel property. The easy peel property means that, for example, when the packaging material 30 having the sealant layer 70 is used to form a container lid, the lid is easily peeled from the flange portion of the container at the lower surface thereof, that is, the sealant layer 70. It is a characteristic. The easy peel property can be expressed, for example, by configuring the sealant layer 70 with two or more kinds of resins and making one resin and another resin incompatible. Examples of the resin capable of exhibiting easy peel properties include a mixed resin of polyethylene and polypropylene such as high-density polyethylene.

When the sealant layer 70 has an easy peel property, as shown in FIG. 11, the sealant layer 70 is positioned on the stretched plastic film 60 side, the inner side of the first layer 71, and the packaging material. And a second layer 72 that constitutes the inner surface 30x of 30. As the first layer 71 and the second layer 72 of the sealant layer 70 having easy peel properties, there are mainly two types such as A type and B type described below.

In the A type sealant layer 70, the first layer 71 is a layer mainly composed of polyethylene, and the second layer 72 is a layer containing a mixed resin of polyethylene and polypropylene. In the second layer 72, the blending ratio of polypropylene is larger than the blending ratio of polyethylene. The mass ratio of polypropylene and polyethylene in the second layer 72 is 6: 4 to 8: 2.

When the packaging material 30 including the A-type sealant layer 70 is used in a packaged product for heat sterilization, the density of polyethylene in the sealant layer 70 is preferably 0.940 g / cm ³ or more.

As the polypropylene in the second layer 72 of the A type sealant layer 70, for example, an ethylene-propylene random copolymer can be used.

In the A type sealant layer 70, the ratio of the thickness of the first layer 71 to the thickness of the second layer 72 can be 5: 1 to 10: 1.

In the B-type sealant layer 70, the first layer 71 is a layer mainly composed of polypropylene, and the second layer 72 is a layer containing a mixed resin of polyethylene and polypropylene. In the second layer 72, the blending ratio of polypropylene is larger than the blending ratio of polyethylene. The mass ratio of polypropylene and polyethylene in the second layer 72 is 6: 4 to 8: 2.

When the packaging material 30 including the B-type sealant layer 70 is used in a packaged product for heat sterilization, the density of the polyethylene in the sealant layer 70 is preferably 0.940 g / cm ³ or more.

As the polypropylene in the first layer 71 of the B type sealant layer 70, for example, an ethylene-propylene block copolymer can be used. As the polypropylene in the second layer 72 of the B type sealant layer 70, for example, an ethylene-propylene random copolymer can be used.

In the B type sealant layer 70, the ratio of the thickness of the first layer 71 to the thickness of the second layer 72 can be 3: 1 to 8: 1.

The sealant layer 70 may be a resin layer provided on the inner surface side of the stretched plastic film 60 by an extrusion method or the like. In this case, the above-mentioned adhesive layer 65 may not exist between the stretched plastic film 60 and the sealant layer 70.

(Other layers)
As shown in FIG. 2, the packaging material 30 may further include a printed layer 36 provided on the stretched plastic film 60. The printed layer 36 is a layer for displaying information on the contents and the packaged product or imparting aesthetics to the packaged product such as the bag 10. The print layer expresses letters, numbers, symbols, figures, patterns, and the like. As a material constituting the printing layer, gravure printing ink or flexographic printing ink can be used. As a specific example of the ink for gravure printing, FINAT manufactured by DIC Graphics Corporation can be given.

FIG. 3 is a cross-sectional view showing a modification of the layer structure of the packaging material 30. As shown in FIG. 3, the packaging material 30 may further include a vapor deposition layer 37 located on the surface on the inner surface 30 x side of the stretched plastic film 60. The packaging material 30 may further include a gas barrier coating film 38 that is located on the surface of the vapor deposition layer 37 and has transparency.

Hereinafter, the vapor deposition layer 37 and the gas barrier coating film 38 will be described.

The vapor deposition layer 37 is a layer provided on the packaging material 30 in order to improve the gas barrier property of the packaging material 30. As a material constituting the vapor deposition layer 37, a metal such as aluminum can be used. The vapor deposition layer 37 may be a transparent vapor deposition layer formed of an inorganic material having transparency, such as aluminum oxide (aluminum oxide) or silicon oxide. In particular, when the printing layer 36 is provided on the inner surface 30x side of the vapor deposition layer 37, the vapor deposition layer 37 is configured as a transparent vapor deposition layer.

The vapor deposition layer 37 functions as a layer having a gas barrier function that prevents permeation of oxygen gas, water vapor, and the like. Two or more vapor deposition layers 37 may be provided. When it has two or more vapor deposition layers 37, each may have the same composition or different compositions. Examples of the method for forming the vapor deposition layer 37 include physical vapor deposition methods (Physical Vapor Deposition method, PVD method) such as vacuum vapor deposition, sputtering, and ion plating, or plasma chemical vapor deposition, thermal Examples thereof include chemical vapor deposition and chemical vapor deposition (chemical vapor deposition, CVD) such as photochemical vapor deposition. Specifically, a vapor deposition layer can be formed on a film formation roller using a roller-type vapor deposition film forming apparatus. The thickness of the vapor deposition layer 37 is, for example, 20 mm or more and 200 mm, preferably 30 mm or more and 150 mm, and more preferably 50 mm or more and 120 mm or less. In addition, the thickness of the vapor deposition layer 37 can be measured by a fundamental parameter method using, for example, a fluorescent X-ray analyzer (trade name: RIX2000 type, manufactured by Rigaku Corporation).

The gas barrier coating film 38 is a layer that functions as a layer that suppresses permeation of oxygen gas, water vapor, and the like. The gas barrier coating film 38 has a general formula R ¹ _n M (OR ² ) _m (wherein R ¹ and R ² represent an organic group having 1 to 8 carbon atoms, M represents a metal atom, n represents an integer of 0 or more, m represents an integer of 1 or more, and n + m represents a valence of M.) and a polyvinyl alcohol as described above And a transparent gas barrier composition that is polycondensed by a sol-gel method in the presence of a sol-gel method catalyst, an acid, water, and an organic solvent. It is done. The gas barrier coating film 38 is preferably transparent.

Next, the layer structure of the lower film 16 will be described.

The layer structure of the lower film 16 is arbitrary as long as it has an inner surface that can be joined to the inner surface of the front film 14 and the inner surface of the back film 15. For example, the packaging material 30 described above may be used as the lower film 16 as with the front film 14 and the back film 15. Alternatively, a film having an inner surface constituted by a sealant layer and a configuration different from that of the packaging material 30 may be used as the lower film 16.

Method for producing a packaging material will be described an example of a method for manufacturing the packaging material 30.

First, the stretched plastic film 60 and the sealant layer 70 described above are prepared. The stretched plastic film 60 is provided with a printing layer 36, a vapor deposition layer 37, a gas barrier coating film 38, and the like as necessary.

Subsequently, the stretched plastic film 60 and the sealant layer 70 are laminated via the adhesive layer 65 by a dry laminating method. Thereby, the packaging material 30 provided with the stretched plastic film 60 and the sealant layer 70 can be obtained.

In the dry laminating method, first, an adhesive composition is applied to one of two laminated films. Subsequently, the applied adhesive composition is dried to volatilize the solvent. Then, two films are laminated | stacked through the adhesive composition after drying. Subsequently, aging is performed for 24 hours or more in an environment of 20 ° C. or higher, for example, in a state where the two laminated films are wound.

Method for producing a bag Next, a method for producing the bag 10 with the packaging material 30 described above. First, the front film 14 and the back film 15 made of the packaging material 30 are prepared. In addition, the lower film 16 in a folded state is inserted between the front film 14 and the back film 15. Subsequently, the inner surfaces of the films are heat-sealed to form seal portions such as the lower seal portion 12a and the side seal portion 13a. Further, the films bonded to each other by heat sealing are cut into an appropriate shape to obtain a bag 10 shown in FIG.

Subsequently, the contents 10 are filled into the bag 10 through the opening 11b of the upper portion 11. Specifically, as shown in FIG. 12, portions of the pair of side seal portions 13 a of the bag 10 that are close to the upper portion 11 are gripped by the pair of chuck portions 105. Further, as indicated by an arrow P in FIG. 12, the chuck portion 105 is moved in such a direction that the interval between the pair of chuck portions 105 becomes narrow in the width direction of the bag 10. Thereby, the surface film 14 and the back film 15 are deformed so as to form the opening 11b in the upper part 11. At this time, as shown in FIG. 12, the suction unit 106 may be attached to the outer surfaces of the front film 14 and the back film 15, and the suction unit 106 may be moved in the direction of the arrow Q. Thereby, it becomes easy to form the opening part 11b. Subsequently, the contents 18 are filled into the bag 10 through the opening 11b. Thereafter, the upper part 11 is heat-sealed to form the upper seal part 11a. Thus, the bag 10 in which the contents 18 are accommodated and sealed can be obtained.

The contents 18 are cooked foods containing moisture, such as curry, stew, and soup. The contents 18 may have a material containing a large amount of oil, such as meat and fish and seasonings for them. In addition to food, items that can be heated by hot water can be stored in the bag 10 as contents. In addition, the bag 10 may contain contents that do not require heating.

In the present embodiment, a high-stiffness polyester film is used as the stretched plastic film 60 of the packaging material 30 constituting the bag 10. For this reason, the packaging material 30 and the bag 10 can have rigidity and puncture resistance. Thereby, for example, when a sharp member with a sharp tip comes into contact with the bag 10, the bag 10 can be prevented from being torn. The puncture strength of the packaging material 30 is preferably 12N or more, and more preferably 13N or more. The method for measuring the piercing strength will be described in the examples described later.

In the present embodiment, since the packaging material 30 constituting the front film 14 and the back film 15 has rigidity, when the chuck portion 105 is moved as shown in FIG. It becomes easy to form. For example, the front film 14 and the back film 15 are each easily deformed so as to have a curved shape that is convex on the outer surface side. Thereby, it becomes easy to ensure the opening width K of the opening part 11b. Moreover, in this Embodiment, since the packaging material 30 which comprises the surface film 14 and the back film 15 has rigidity, it is hard to produce a wrinkle in the surface film 14 and the back film 15. For this reason, the adsorption | suction part 106 tends to adsorb | suck to the outer surface of the surface film 14 and the back film 15. This can also contribute to securing the opening width K of the opening 11b.

Opening method of bag will now be described opening method of bag 10. The consumer opens the bag 10 by tearing the bag 10 along the first direction D1. In this case, it is preferable that the sealant layer 70 of the packaging material 30 constituting the bag 10 has a high tensile elastic modulus. For example, it is preferable to use the second type sealant layer 70 described above. Thereby, tearing property can be given to the packaging material 30 and the bag 10. Therefore, for example, when a consumer tears and opens the bag 10, it can suppress that a tear direction deviates from the 1st direction D1.

(Modification)
Various modifications can be made to the above-described embodiments. Hereinafter, modified examples will be described with reference to the drawings as necessary. In the following description and the drawings used in the following description, the same reference numerals as those used for the corresponding parts in each of the above embodiments are used for the parts that can be configured in the same manner as in each of the above embodiments. And redundant description is omitted. In addition, when it is clear that the operational effects obtained in each of the above-described embodiments can be obtained in the modification, the description thereof may be omitted.

(Bag variant)
FIG. 13 is a diagram illustrating another example of the bag 10 including the packaging material 30. The bag 10 shown in FIG. 13 is different only in that it further includes a steam release mechanism 20, and the other configuration is substantially the same as the bag 10 shown in FIG. In the bag 10 shown in FIG. 13, the same parts as those in the bag 10 shown in FIG.

As shown in FIG. 13, the bag 10 includes a steam release mechanism 20 for releasing steam generated when the contents stored in the storage portion 17 are heated. The steam release mechanism 20 allows the inside and the outside of the bag 10 to communicate with each other when the pressure of the steam reaches a predetermined value or more to escape the steam, and suppresses the steam from being released from a place other than the steam release mechanism 20. ,It is configured.

In addition, when the bag 10 provided with the vapor venting mechanism 20 is heated using a microwave oven or the like, the internal pressure of the bag 10 may not increase to the extent that the vapor is released from the vapor venting mechanism 20 to the outside. That is, depending on how the bag 10 is used, the steam release mechanism 20 may have a low probability of developing a function of escaping steam to the outside. Even in this case, by providing the vapor venting mechanism 20 in the bag 10, it is possible to further reduce the probability that the vapor will escape from a place other than the vapor venting mechanism 20 or the bag 10 may rupture.

In the example shown in FIG. 13, the steam release mechanism 20 includes a steam release seal portion 20 a that protrudes from the side seal portion 13 a toward the inside of the bag 10, and a non-seal that is isolated from the housing portion 17 by the steam release seal portion 20 a. Part 20b. The non-seal portion 20 b communicates with the outside of the bag 10. When the pressure in the accommodating portion 17 is increased by being heated by a microwave oven or the like, the steam release seal portion 20a is peeled off. The steam in the housing part 17 can escape to the outside of the bag 10 through the peeling part of the steam release seal part 20a and the non-seal part 20b. At this time, since the packaging material 30 has heat resistance, it is possible to suppress the formation of a hole in the packaging material 30 or the formation of wrinkles in the packaging material 30 during heating.

It should be noted that the configuration of the steam release mechanism 20 is not limited to the configuration shown in FIG. The configuration of the steam release mechanism 20 is arbitrary as long as the housing portion 17 and the outside of the bag 10 can be communicated with each other when the steam pressure exceeds a predetermined value.

For example, as shown in FIG. 14, the surface film 14 may include a palm portion 14a in which the inner surfaces of the surface film 14 are partially overlapped. The palm portion 14a can be configured, for example, by folding back with a folding portion 14f so as to form a pleat on one surface film 14. Further, the palm portion 14a may be configured by overlapping a part of the two surface films 14.

In the palm portion 14a, a palm seal portion 14b extending from one side seal portion 13a to the other side seal portion 13a is formed. In this case, the steam release mechanism 20 includes, for example, a steam release seal part 20a that protrudes from the palm seal part 14b toward the housing part 17, and a non-seal part 20b that is surrounded by the steam release seal part 20a and the joint seal part 14b. And a through hole 20c formed in the surface film 14 in the non-seal portion 20b.

Also in this modified example, when the pressure in the accommodating portion 17 increases, the steam release seal portion 20a is peeled off, and the accommodating portion 17 and the non-seal portion 20b communicate with each other. The steam that has flowed into the non-seal portion 20b from the housing portion 17 through the peeled portion of the steam release seal portion 20a passes through the through hole 20c and escapes to the outside of the bag 10.

In addition, the bag 10 shown in FIG. 14 is arrange | positioned in a microwave oven so that the back surface film 15 may contact the turntable or lower surface (flat table) of a microwave oven over a wide area. For this reason, compared with the self-supporting bag 10 as shown in FIG. Moreover, since the area of the part where the bag 10 is in contact with the microwave oven is large, even if the bag 10 is softened by heating, the position of the liquid level of the contents is unlikely to change. For this reason, in the heating process using a microwave oven, it is difficult for the contents to adhere to the inner surface of the front film 14 or the back film 15 above the liquid level of the contents. Thereby, it can suppress that the phenomenon that the content adhering to the inner surface of the surface film 14 or the back surface film 15 overheats excessively and a hole is formed in the surface film 14 or the back surface film 15 arises.

15A and 15B are a longitudinal sectional view and a plan view showing a container 110 with a lid, which is an example of the use of the packaging material 30. FIG. The lidded container 110 includes a container main body 112 manufactured by sheet molding such as drawing or injection molding, and a lid member 114 joined to the container main body 112. The container main body 112 includes a bottom surface 112a and a side surface 112b, and a flange portion 113 that spreads outward in the horizontal direction from the upper end of the side surface 112b. The lid member 114 is joined to the upper surface of the flange portion 113 of the container main body 112 via a seal portion 116. The lid 114 may include the packaging material 30 described above having a high stiffness polyester film. By configuring the lid member 114 using the packaging material 30 described above, the lid member 114 can have excellent piercing strength. Thereby, when the sharp member with the pointed tip contacts the lid member 114, the lid member 114 can be prevented from being broken. Moreover, when the container 110 with a lid | cover falls, it can suppress that the container 110 with a lid | cover is damaged and the content leaks out.

The sealant layer 70 of the packaging material 30 constituting the lid material 114 may have an easy peel property. That is, the sealant layer 70 of the packaging material 30 constituting the lid member 114 includes a first layer 71 mainly composed of polyethylene or polypropylene, and a second layer 72 comprising a mixed resin of polyethylene and polypropylene and constituting the inner surface 30x. , May be included.

In the present application, products for packaging articles such as the bag 10 and the lidded container 110 are also referred to as packaging products.

In the packaging material 30 used in the packaged product having the steam release mechanism 20, the strength of the seal portion (hereinafter also referred to as hot seal strength) constituted by the sealant layer 70 at a high temperature, for example, at 100 ° C. or higher. It is preferable that the seal strength is extremely small at low temperatures, for example, at room temperature. For example, it is preferable that the hot seal strength at 100 ° C. is 1/3 or less, preferably 1/4 or less, of the seal strength at 25 ° C. (hereinafter also referred to as room temperature seal strength). For example, the hot seal strength at a width of 15 mm at 100 ° C. is 30 N or less, preferably 25 N or less, more preferably 20 N or less, and even more preferably 15 N or less. Further, the normal temperature seal strength at a width of 15 mm at 25 ° C. is 23 N or more, preferably 40 N or more, more preferably 50 N or more, and further preferably 60 N or more. Due to the low hot seal strength, when the bag 10 provided with the steam release mechanism 20 is heated using a microwave oven, the steam release seal portion 20a is easily peeled off, and the steam in the housing portion 17 is exposed to the outside of the bag 10. It becomes easy to come off. For this reason, it can suppress that the internal pressure of the accommodating part 17 becomes excessive, and, thereby, it can suppress that the packaging material 30 damages at the time of a heating. The seal strength can be measured according to JIS Z1707 7.5. As the measuring device, for example, RTC-1310A, a tensile tester with a thermostatic bath manufactured by Orientec Co., Ltd. can be used.

(Other variations of bags)
In the above-described embodiment, an example in which the bag 10 is a gusset type bag has been shown, but the specific configuration of the bag 10 is not particularly limited. For example, the bag 10 may be a so-called four-side sealed bag formed by joining the inner surfaces of the front film 14 and the back film 15 made of the packaging material 30 at the upper part 11, the lower part 12 and the side part 13.

Second Embodiment Next, a second embodiment of the present invention will be described. Similarly to the first embodiment described above, the second embodiment also relates to a packaging product including the packaging material and the packaging material. First, a problem to be solved by the second embodiment will be described.

Conventionally, various packaging materials have been developed and proposed for filling and packaging various articles such as foods and drinks, pharmaceuticals, chemicals, cosmetics, and others. In such a packaging material, various physical properties are required as the packaging material, although it varies depending on the purpose of packaging, the contents to be filled, the storage / distribution of the packaged product, and the like. For example, as one of those physical properties, there is a gas barrier property that prevents permeation of oxygen, water vapor, and the like.

Conventionally, various gas barrier materials that prevent permeation of oxygen and water vapor have been developed and proposed. For example, aluminum foil or nylon film or polyethylene terephthalate film having a polyvinylidene chloride resin coating film, polyvinyl alcohol film, saponified ethylene-vinyl acetate copolymer film, polyacrylonitrile resin film, etc. Gas barrier materials have been developed and proposed.

Further, in recent years, a transparent barrier film having a structure in which a vapor-deposited layer of an inorganic oxide such as silicon oxide or aluminum oxide is provided on a plastic substrate, or a vapor-deposited layer of a metal such as aluminum is provided. Barrier films and the like have also been proposed. For example, Japanese Patent Laid-Open No. 2007-303000 proposes producing a barrier film by forming a vapor deposition layer of an inorganic oxide on a nylon film.

By the way, the packaging material is required to have a characteristic that prevents the bag from being torn even when a sharp member with a sharp tip contacts the packaging bag, that is, a so-called puncture resistance.

This embodiment is intended to provide a packaging material that can effectively solve such problems.

Next, the means for solving the problem will be described.

The present embodiment includes a barrier laminate film and a sealant layer positioned inside the barrier laminate film, and the barrier laminate film is provided on a base material, the base material, and a metal. Or a vapor-deposited layer containing an inorganic compound, and the base material contains polyester as a main component, and a value obtained by dividing the tensile strength of the base material by the tensile elongation in at least one direction is 2.0 [MPa. /%] Or more.

In the packaging material according to the present embodiment, the sealant layer may include 90% by mass or more of polypropylene.

In the packaging material according to the present embodiment, the sealant layer may include linear low density polyethylene having a melting point of 100 ° C. or higher.

In the packaging material according to the present embodiment, the sealant layer includes a first layer containing polypropylene and high-density polyethylene, and a first layer containing polypropylene or high-density polyethylene, which is positioned closer to the barrier laminate film than the first layer. And may have two layers.

In the packaging material according to the present embodiment, the piercing strength of the base material of the barrier laminate film may be 9.5 N or more.

In the packaging material according to the present embodiment, the base material of the barrier laminate film may have a loop stiffness of 0.0017 N or more in the flow direction and the vertical direction, and may contain polyester as a main component.

In the packaging material according to the present embodiment, the base material of the barrier laminate film may contain polybutylene terephthalate as a main component.

In the packaging material according to the present embodiment, the barrier laminate film may further include a gas barrier coating film provided on the vapor deposition layer.

In the packaging material according to the present embodiment, the vapor deposition layer of the barrier laminate film may be a transparent vapor deposition layer containing an inorganic compound.

In the packaging material according to the present embodiment, the vapor deposition layer of the barrier laminate film is a transparent vapor deposition layer containing aluminum oxide, the transparent vapor deposition layer includes a transition region, and the transition region includes the barrier laminate. The peak position of element-bonded Al ₂ O ₄ H detected by etching the film from the transparent vapor deposition layer side using time-of-flight secondary ion mass spectrometry (TOF-SIMS), and the transparent vapor deposition layer And the ratio of the thickness of the transition region to the thickness of the transparent vapor deposition layer may be 5% or more and 60% or less.

This embodiment is a packaged product composed of the packaging material described above.

According to this embodiment, a packaging material having gas barrier properties and strength can be provided.

Hereinafter, the second embodiment will be described in detail. The packaging material 210 in the second embodiment is characterized by having a high stiffness polyester film provided with a vapor deposition layer. In the following description, the same names are used for portions that can be configured in the same manner as in the first embodiment described above, and redundant descriptions may be omitted. Moreover, when it is clear that the operational effects obtained in the first embodiment described above can be obtained in the second embodiment, the description thereof may be omitted.

FIG. 16 is a cross-sectional view showing an example of the packaging material 210 according to the present embodiment. The packaging material 210 includes a barrier laminate film 205, a printed layer 218, a first adhesive layer 213, and a sealant layer 212 in this order from the outside to the inside. The barrier laminate film 205 includes at least a base material 201 and a vapor deposition layer 202 in this order. The barrier laminate film 205 may further include a gas barrier coating film 203 located on the vapor deposition layer 202. The base material 201 constitutes the outer surface 210 y of the packaging material 210, and the sealant layer 212 constitutes the inner surface 210 x of the packaging material 210.

In this embodiment, the outer surface is a surface located on the outermost side in the packaging material 210, and the inner surface is a surface located on the innermost side in the packaging material 210. Further, in the present application, the term “order” in descriptions such as “provide in this order” and “stacked in order” represents the order in the direction from the outside to the inside unless otherwise specified.

FIG. 17 is a cross-sectional view showing a modification of the packaging material according to the present embodiment. The example of FIG. 17 is different only in that the sealant layer 212 includes the first layer 2121 and the second layer 2122 positioned closer to the barrier laminate film 205 than the first layer 2121. Is the same as the packaging material 210 shown in FIG. In the example shown in FIG. 17, the first layer 2121 of the sealant layer 212 constitutes the inner surface 210 x of the packaging material 210. The thickness of the packaging material 210 is, for example, 60 μm or more, 70 μm or more, 80 μm or more, or 90 μm or more. Further, the thickness of the packaging material 210 may be 120 μm or less, 110 μm or less, or 100 μm or less.

Hereinafter, the film and layers constituting the packaging material 210 will be described. First, the barrier laminate film 205 will be described.

[Base material]
The substrate 201 used for the barrier laminate film 205 is a polyester film containing polyester as a main component. The base material 201 contains, for example, 51% by mass or more of polyester. The polyester is at least one aromatic dicarboxylic acid selected from terephthalic acid, isophthalic acid and 2,6-naphthalenedicarboxylic acid, and at least selected from ethylene glycol, 1,3-propanediol and 1,4-butanediol. A polyester mainly composed of an aromatic polyester composed of one kind of aliphatic alcohol is preferred. For example, the polyester includes polyethylene terephthalate (hereinafter also referred to as PET), polybutylene terephthalate (hereinafter also referred to as PBT), and the like.

In order to prevent the bag from tearing when a sharp member with a sharp tip comes into contact with a packaging bag made of a packaging material including the barrier laminate film 205, the base of the barrier laminate film 205 is used. It is preferable that the material 201 has resistance such as puncture resistance. Therefore, in the present embodiment, it is proposed to use either a high stiffness PET film or a PBT film as the base material 201. Thereby, for example, the puncture strength of the base material 201 can be increased. For example, the puncture strength of the base material 201 can be set to 9.5 N or more, more preferably 10 N or more. Further, the ratio of the tensile strength to the tensile elongation of the substrate 201 can be increased. For example, in at least one direction, the value obtained by dividing the tensile strength of the substrate by the tensile elongation is 2.0 [MPa /%] or more. Thereby, the rigidity for suppressing that a bag is torn even when a sharp member with a sharp tip contacts the packaging material including the barrier laminate film 205 can be provided.

Hereinafter, the high stiffness PET film and the PBT film will be described in detail. First, the high stiffness PET film will be described.

The high stiffness PET film is a biaxially stretched PET having a loop stiffness of 0.0017 N or more in at least one direction and containing 51 mass% or more of PET, as in the case of the first embodiment described above. It is a film. The thickness of the high stiffness PET film is preferably 5 μm or more, more preferably 7 μm or more. The thickness of the high stiffness PET film is preferably 25 μm or less, and more preferably 20 μm or less. The loop stiffness measurement method is the same as that in the first embodiment described above.

The preferred mechanical properties of the high stiffness PET film will be further described.
The puncture strength of the high stiffness PET film is preferably 9.5 N or more, more preferably 10.0 N or more.

The tensile strength and tensile elongation of the high stiffness PET film in the flow direction, the value obtained by dividing the tensile strength of the high stiffness PET film by the tensile elongation, the thermal shrinkage rate, and the tensile elastic modulus are the same as those in the first embodiment. Since it is the same as the case of the stiffness polyester film, the description is omitted.

In the production process of the high stiffness PET film, as in the case of the high stiffness polyester film, for example, first, a PET film obtained by melting and molding polyethylene terephthalate is subjected to 90 ° C. in the flow direction and the vertical direction, respectively. A first stretching step of stretching 3 to 4.5 times at ˜145 ° C. is performed. Subsequently, a second stretching step is performed in which the plastic film is stretched 1.1 to 3.0 times at 100 to 145 ° C. in the flow direction and the vertical direction, respectively. Thereafter, heat setting is performed at a temperature of 190 ° C. to 220 ° C. Subsequently, in the flow direction and the vertical direction, a relaxation treatment (treatment for reducing the film width) of about 0.2% to 2.5% is performed at a temperature of 100 ° C. to 190 ° C. In these steps, a high stiffness PET film having the above-mentioned mechanical properties can be obtained by adjusting the stretching ratio, stretching temperature, heat setting temperature, and relaxation treatment rate.

The PET constituting the high stiffness PET film may include biomass-derived PET, as in the case of the first embodiment described above. In this case, the high stiffness PET film may be composed of only biomass-derived PET. Alternatively, the high stiffness PET film may be composed of biomass-derived PET and fossil fuel-derived PET. The biomass-derived PET contained in the high stiffness PET film, the biomass degree of the high stiffness PET film, and the like are the same as in the case of the high stiffness polyester film of the first embodiment described above, and thus the description thereof is omitted.

Next, the PBT film will be described. The PBT film is a stretched plastic film containing 51% by mass or more of PBT. Hereinafter, advantages of the base material 201 containing PBT will be described.

PBT has excellent heat resistance. For this reason, it can suppress that the base material 201 deform | transforms or the intensity | strength of the base material 201 falls when performing a boil process and a retort process to the packaging bag which accommodates contents, such as foodstuffs. The retort process is a process of heating the packaging bag in a pressurized state using steam or heated hot water after filling the packaging bag with the contents and sealing the packaging bag. The temperature of retort processing is 120 degreeC or more, for example. The boil process is a process of filling the packaging container with the contents and sealing the packaging container, and then bathing the packaging container under atmospheric pressure. The temperature of boil processing is 90 degreeC or more and 100 degrees C or less, for example.

Also, PBT has high strength. For this reason, the packaging bag can be provided with puncture resistance as in the case where the packaging material 210 constituting the packaging bag contains nylon. The puncture strength of the PBT film is preferably 9.5 N or more, more preferably 10.0 N or more.

The tensile strength of the PBT film in the flow direction is preferably 150 MPa or more, more preferably 180 MPa or more. The tensile strength of the PBT film in the vertical direction is preferably 250 MPa or more, and more preferably 280 MPa or more.
The tensile elongation of the PBT film in the flow direction is preferably 220% or less, and more preferably 200% or less. The tensile elongation of the PBT film in the vertical direction is preferably 120% or less, and more preferably 110% or less.
Preferably, in at least one direction, a value obtained by dividing the tensile strength of the PBT film by the tensile elongation is 2.0 [MPa /%] or more. For example, the value obtained by dividing the tensile strength of the PBT film in the vertical direction (TD) by the tensile elongation is preferably 2.0 [MPa /%] or more, more preferably 2.2 [MPa /%] or more. Yes, more preferably 2.5 [MPa /%] or more.

Also, PBT has a characteristic that it is less likely to absorb moisture than nylon. For this reason, even if it is a case where the base material 201 containing PBT is arrange | positioned on the outer surface of the packaging material 210, it suppresses that the base material 201 absorbs a water | moisture content and the laminate strength of the packaging material 210 falls. it can.

Hereinafter, the configuration of the base material 201 including PBT will be described in detail. As the configuration of the base material 201 containing PBT in the present embodiment, any of the following first configuration or second configuration may be adopted.

[First Configuration of Substrate Containing PBT]
The content of PBT in the substrate 201 according to the first configuration is preferably 51% by mass or more, more preferably 60% by mass or more, further 70% by mass or more, particularly preferably 75% by mass or more, and most preferably. 80% by mass or more. By making the content of PBT 51% by mass or more, the base material 201 can have excellent impact strength and pinhole resistance.

PBT used as a main constituent component is preferably 90 mol% or more, more preferably 95 mol% or more, still more preferably 98 mol% or more, most preferably 100 mol% or more of terephthalic acid as a dicarboxylic acid component. Mol%. 1,4-butanediol as the glycol component is preferably 90 mol% or more, more preferably 95 mol% or more, still more preferably 97 mol% or more, and most preferably 1,4-butanediol during polymerization. It is not included except by-products generated by the ether bond of butanediol.

The base material 201 may contain a polyester resin other than PBT. Thereby, for example, the film formability when the film-like base material 201 is biaxially stretched and the mechanical properties of the base material 201 can be adjusted.
Polyester resins other than PBT include polyester resins such as PET, polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), and polypropylene terephthalate (PPT), as well as isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, and biphenyldicarboxylic acid. , PBT resin copolymerized with dicarboxylic acid such as cyclohexanedicarboxylic acid, adipic acid, azelaic acid, sebacic acid, ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, neopentyl glycol, 1,5 -Diols such as pentanediol, 1,6-hexanediol, diethylene glycol, cyclohexanediol, polyethylene glycol, polytetramethylene glycol, polycarbonate diol Min can be mentioned copolymerized PBT resin.

The amount of the polyester resin other than PBT is preferably 49% by mass or less, and more preferably 40% by mass or less. If the addition amount of the polyester resin other than PBT exceeds 49% by mass, the mechanical properties as PBT may be impaired, and impact strength, pinhole resistance, and drawability may be insufficient.

The base material 201 may include a polyester-based and polyamide-based elastomer obtained by copolymerizing at least one of a flexible polyether component, a polycarbonate component, and a polyester component as an additive. Thereby, the pinhole resistance at the time of bending can be improved. The additive amount of the additive is, for example, 20% by mass. If the additive amount exceeds 20% by mass, the effect as an additive may be saturated, or the transparency of the substrate 201 may be reduced.

An example of a method for producing the film-like substrate 201 according to the first configuration will be described. Here, a method for producing the film-like substrate 201 by a casting method will be described. More specifically, a method of casting a resin having the same composition in multiple layers during casting will be described.

Since PBT has a high crystallization speed, crystallization proceeds even during casting. At this time, when cast as a single layer without being multi-layered, there is no barrier that can suppress the growth of the crystal, so the crystal grows to a large size, and the resulting unstretched original fabric is obtained. The yield stress of becomes higher. For this reason, it becomes easy to fracture when the unstretched original fabric is biaxially stretched. Moreover, it is possible that the yield stress of the obtained biaxially stretched film becomes high and the moldability of the biaxially stretched film becomes insufficient.
On the other hand, if the same resin is multilayered at the time of casting, the stretching stress of the unstretched sheet can be reduced. For this reason, stable biaxial stretching is possible, and the yield stress of the obtained biaxially stretched film is reduced. Thereby, a flexible and high breaking strength film can be obtained.

FIG. 18 is a cross-sectional view showing an example of the layer structure of the base material 201. When the base material 201 is produced by casting the resin in multiple layers, the base material 201 includes a multilayer structure including a plurality of layers 201a, as shown in FIG. Each of the plurality of layers 201a includes PBT as a main component. For example, each of the plurality of layers 201a preferably includes 51% by mass or more of PBT, and more preferably includes 60% by mass or more of PBT. In the plurality of layers 201a, the (n + 1) th layer 201a is directly stacked on the nth layer 201a. That is, no adhesive layer or adhesive layer is interposed between the plurality of layers 201a.

The reason why the properties of the PBT film are improved by multilayering is estimated as follows. When the resins are laminated, even if the resin composition is the same, a layer interface exists, and crystallization is accelerated by the interface. On the other hand, the growth of large crystals beyond the layer thickness is suppressed. For this reason, it is considered that the size of the crystal (spherulite) becomes small.

As a specific method for reducing the size of spherulites by multilayering, a general multilayering apparatus (multilayer feed block, static mixer, multilayer multimanifold, etc.) can be used. For example, a method of laminating thermoplastic resins sent from different flow paths using two or more extruders in multiple layers using a feed block, a static mixer, a multi-manifold die, or the like can be used. In addition, when multilayering resin of the same composition, it is also possible to introduce the above multilayering apparatus into the melt line from the extruder to the die using only one extruder.

The substrate 201 is composed of a multilayer structure including at least 10 layers, preferably 60 layers or more, more preferably 250 layers or more, and still more preferably 1000 layers or more. By increasing the number of layers, the size of spherulites in the unstretched raw PBT can be reduced, and the subsequent biaxial stretching can be carried out stably. Moreover, the yield stress of PBT in the state of a biaxially stretched film can be made small. Preferably, the diameter of the spherulite in the unstretched raw PBT is 500 nm or less.

The stretching temperature (hereinafter also referred to as MD stretching temperature) in the longitudinal stretching direction (hereinafter referred to as MD) when producing a biaxially stretched film by biaxially stretching the unstretched raw material of PBT is preferably 40 ° C. or higher. Yes, more preferably 45 ° C or higher. By setting the MD stretching temperature to 40 ° C. or higher, the film can be prevented from being broken. Moreover, MD extending | stretching temperature becomes like this. Preferably it is 100 degrees C or less, More preferably, it is 95 degrees C or less. The phenomenon that the orientation of the biaxially stretched film does not occur can be suppressed by setting the MD stretching temperature to 100 ° C. or lower.

The draw ratio in MD (hereinafter also referred to as MD draw ratio) is preferably 2.5 times or more. Thereby, a biaxially stretched film can be oriented and a favorable mechanical characteristic and uniform thickness can be implement | achieved. MD stretch ratio is 5 times or less, for example.

The stretching temperature (hereinafter also referred to as TD stretching temperature) in the transverse stretching direction (hereinafter also referred to as TD) is preferably 40 ° C. or higher. By setting the TD stretching temperature to 40 ° C. or higher, the film can be prevented from being broken. The TD stretching temperature is preferably 100 ° C. or lower. By setting the TD stretching temperature to 100 ° C. or lower, the phenomenon that the orientation of the biaxially stretched film does not occur can be suppressed.

The stretching ratio in TD (hereinafter also referred to as TD stretching ratio) is preferably 2.5 times or more. Thereby, a biaxially stretched film can be oriented and a favorable mechanical characteristic and uniform thickness can be implement | achieved. MD stretch ratio is 5 times or less, for example.

TD relaxation rate is preferably 0.5% or more. Thereby, it can suppress that a fracture | rupture arises at the time of heat setting of the biaxially stretched film of PBT. The TD relaxation rate is preferably 10% or less. Thereby, sagging etc. arise in a biaxially stretched film of PBT, and it can control that thickness unevenness generate | occur | produces.

The thickness of the layer 201a of the substrate 201 shown in FIG. 18 is preferably 3 nm or more, and more preferably 10 nm or more. The thickness of the layer 201a is preferably 200 nm or less, more preferably 100 nm or less.
Moreover, the thickness of the base material 201 is preferably 9 μm or more, more preferably 12 μm or more. The thickness of the base material 201 is preferably 25 μm or less, more preferably 20 μm or less. By setting the thickness of the base material 201 to 9 μm or more, the base material 201 has sufficient strength. Moreover, the base material 201 comes to show the outstanding moldability by making the thickness of the base material 201 into 25 micrometers or less. For this reason, the process which processes the packaging material 210 containing the base material 201 and manufactures a packaging bag can be implemented efficiently.

[Second Configuration of Substrate Containing PBT]
The base material 201 according to the second configuration is made of a single layer film containing polyester having butylene terephthalate as a main repeating unit. For example, the base material 201 is mainly composed of 1,4-butanediol as a glycol component or an ester-forming derivative thereof and terephthalic acid as a dibasic acid component or an ester-forming derivative thereof, and condenses them. Homo- or copolymer-type polyester obtained. The content of PBT in the base material 201 according to the second configuration is preferably 51% by mass or more, more preferably 60% by mass or more, further preferably 70% by mass or more, further preferably 80% by mass or more, and most preferably. Is 90% by mass or more. Moreover, it is preferable that the base material 201 which concerns on a 2nd structure is comprised only with the polybutylene terephthalate and the additive.

In order to impart mechanical strength to the substrate 201, PBT having a melting point of 200 ° C. or more and 250 ° C. or less and an IV value (intrinsic viscosity) of 1.10 dl / g or more and 1.35 dl / g or less Is preferred. Furthermore, those having a melting point of 215 ° C. or more and 225 ° C. or less and an IV value of 1.15 dl / g or more and 1.30 dl / g or less are particularly preferable. These IV values may be satisfied by the entire material constituting the substrate 201. The IV value can be calculated based on JIS K 7367-5: 2000.

The substrate 201 according to the second configuration may include a polyester resin other than PBT such as PET in a range of 30% by mass or less. When the base material 201 contains PET in addition to PBT, PBT crystallization can be suppressed, and the stretchability of the PBT film can be improved. As PET mix | blended with PBT of the base material 201, the polyester which uses ethylene terephthalate as a main repeating unit can be used. For example, a homotype mainly composed of ethylene glycol as a glycol component and terephthalic acid as a dibasic acid component can be preferably used. In order to impart good mechanical strength characteristics, among PET, those having a melting point of 240 ° C. or more and 265 ° C. or less and an IV value of 0.55 dl / g or more and 0.90 dl / g or less are preferable. Furthermore, those having a melting point of 245 ° C. or more and 260 ° C. or less and an IV value of 0.60 dl / g or more and 0.80 dl / g or less are particularly preferable.
By setting the blending amount of PET to 30% by mass or less, it is possible to suppress the unstretched raw fabric and the stretched film from becoming too rigid. Thereby, a stretched film becomes brittle and it can suppress that the pressure resistance strength, impact strength, puncture strength, etc. of a stretched film fall. Moreover, it is possible to suppress the occurrence of stretching failure when the unstretched raw fabric is stretched.

The substrate 201 is made of a lubricant, an anti-blocking agent, an inorganic extender, an antioxidant, an ultraviolet absorber, an antistatic agent, a flame retardant, a plasticizer, a colorant, a crystallization inhibitor, and a crystallization accelerator as necessary. Etc. may be contained. Further, the polyester resin pellets used as the raw material of the base material 201 has a moisture content of 0.05% by weight or less, preferably 0.01% by weight or less before heating and melting in order to avoid a decrease in viscosity due to hydrolysis during heating and melting. It is preferable to use after sufficiently pre-drying so that

An example of a method for producing the film-like substrate 201 according to the second configuration will be described.

In order to stably produce the film of the base material 201 having the above-described configuration, it is important to suppress the crystal growth in the unstretched raw fabric state. Specifically, when forming the film by cooling the extruded PBT melt, the crystallization temperature region of the polymer is cooled at a certain rate or more, that is, the raw fabric cooling rate is an important factor. The raw fabric cooling rate is, for example, 200 ° C./second or more, preferably 250 ° C./second or more, particularly preferably 350 ° C./second or more. Since the unstretched original film formed at a high cooling rate maintains a low crystalline state, the stability of the bubbles during stretching is improved. Furthermore, since film formation at high speed is possible, film productivity is also improved. When the cooling rate is less than 200 ° C./sec, it is considered that the crystallinity of the obtained unstretched original fabric is increased and the stretchability is lowered. In extreme cases, the stretching bubble may burst and stretching may not continue.

It is preferable that the unstretched raw material containing PBT as a main component is conveyed to a space where biaxial stretching is performed while maintaining the atmospheric temperature at 25 ° C. or lower, preferably 20 ° C. or lower. Thereby, even if it is a case where residence time becomes long, the crystallinity of the unstretched original fabric immediately after film-forming can be maintained.

The biaxial stretching method for obtaining a stretched film by stretching an unstretched raw fabric is not particularly limited. For example, the longitudinal direction and the lateral direction may be simultaneously stretched by the tubular method or the tenter method, or the longitudinal direction and the lateral direction may be sequentially stretched. Among these, the tubular method can obtain a stretched film having a good balance of physical properties in the circumferential direction, and is particularly preferably employed.

In the tubular method, the unstretched raw material introduced into the stretching space is inserted between a pair of low-speed nip rolls, and then heated by a stretching heater while air is being pressed therein. After stretching, air is blown onto the stretched film by a cooling shoulder air ring. The stretching ratio is preferably 2.7 times or more and 4.5 times or less for MD and TD, respectively, in consideration of stretching stability, strength physical properties of the stretched film, transparency, and thickness uniformity. By setting the draw ratio to 2.7 times or more, it is possible to sufficiently ensure the tensile elastic modulus and impact strength of the stretched film. In addition, by setting the draw ratio to 4.5 times or less, it is possible to suppress the occurrence of excessive molecular chain distortion due to stretching, and to suppress the occurrence of breakage and puncture during the stretching process, so that the stretched film can be stabilized. Can be produced.

The stretching temperature is preferably 40 ° C. or higher and 80 ° C. or lower, and particularly preferably 45 ° C. or higher and 65 ° C. or lower. Since the unstretched original fabric produced at the above-described high cooling rate has low crystallinity, the unstretched original fabric can be stably stretched even when the stretching temperature is relatively low. Further, by setting the stretching temperature to 80 ° C. or less, it is possible to suppress stretching bubble shaking and obtain a stretched film with good thickness accuracy. In addition, by setting the stretching temperature to 40 ° C. or higher, it is possible to suppress the occurrence of excessive stretch-oriented crystallization due to low-temperature stretching, thereby preventing whitening of the film.

The base material 201 produced as described above is constituted by a single layer containing, for example, polyester having butylene terephthalate as a main repeating unit. According to the above-described production method, since the unstretched raw film is formed at a high cooling rate, even when the unstretched raw fabric is constituted by a single layer, a low crystalline state can be maintained, For this reason, an unstretched original fabric can be extended | stretched stably.

When the base material 201 contains PBT, the heat resistance of the barrier laminate film 205 and the heat resistance of the packaging material 210 including the barrier laminate film 205 can be increased. For example, the tensile elastic modulus of the barrier laminate film 205 and the packaging material 210 can be sufficiently increased. In particular, the tensile elastic modulus (hereinafter also referred to as hot tensile elastic modulus) of the barrier laminate film 205 and the packaging material 210 in a high-temperature atmosphere, for example, an atmosphere at 100 ° C. can be sufficiently increased.

Also in the present embodiment, when the packaging material 210 includes a high stiffness PET film or a PBT film, the puncture strength of the packaging material 210 can be increased as in the case of the first embodiment described above. The puncture strength of the packaging material 210 is, for example, 12N or more, and may be 13N or more. In addition, the strength of the packaging material 210 can be increased as in the case of the first embodiment described above. For example, the loop stiffness of the packaging material 210 per unit thickness of the packaging material 30 can be increased. The value obtained by dividing the loop stiffness of the packaging material 30 in at least one direction by the thickness of the packaging material 210 is, for example, 0.00085 N / μm or more, may be 0.00090 N / μm or more, and 0.00095 N / μm. The above may be sufficient, and 0.00100 N / micrometer or more may be sufficient. For example, the value obtained by dividing the loop stiffness of the packaging material 210 in the flow direction (MD) by the thickness of the packaging material 210 is, for example, 0.00085 N / μm or more, and may be 0.00090 N / μm or more. It may be greater than or equal to 00095 N / μm and may be greater than or equal to 0.00100 N / μm. The value obtained by dividing the loop stiffness of the packaging material 210 in the vertical direction (TD) by the thickness of the packaging material 30 is, for example, 0.00080 N / μm or more, and may be 0.00085 N / μm or more. It may be 9090 N / μm or more, or 0.00095 N / μm or more.

[Deposition layer]
Next, the vapor deposition layer 202 of the barrier laminate film 205 will be described.

The vapor deposition layer 202 is a thin film having a gas barrier performance that blocks or blocks permeation of oxygen gas, water vapor, and the like. The vapor deposition layer 202 may be a metal layer containing a light-shielding metal such as aluminum, or may be a transparent vapor deposition layer formed of an inorganic compound having transparency. For example, the vapor deposition layer 202 is a transparent vapor deposition layer formed of an inorganic oxide having transparency.

Hereinafter, the case where the vapor deposition layer 202 is a transparent vapor deposition layer is demonstrated. The inorganic oxide forming the vapor deposition layer 202 contains, for example, an aluminum compound as a main component, which contains at least aluminum oxide or aluminum nitride, carbide, hydroxide alone or a mixture thereof. For example, the inorganic oxide contains aluminum oxide as a main component.
The vapor deposition layer 202 may be a layer containing a silicon compound as a main component. For example, the inorganic oxide layer contains silicon oxide (silicon oxide) as a main component.
Furthermore, the vapor deposition layer 202 contains an aluminum compound such as the above-described aluminum oxide as a main component, and further includes silicon oxide, silicon nitride, silicon oxynitride, silicon carbide, magnesium oxide, titanium oxide, tin oxide, and indium oxide. Further, it may be a layer containing a metal oxide such as zinc oxide or zirconium oxide, or a metal nitride, carbide or mixture thereof.

The thickness of the vapor deposition layer 202 is preferably 3 nm or more and 50 nm or less, and more preferably 9 nm or more and 30 nm or less.

(Gas barrier coating film)
When the vapor deposition layer 202 is a transparent vapor deposition layer, the gas barrier coating film 203 of the barrier multilayer film 205 protects the vapor deposition layer 202 mechanically and chemically and improves the barrier property of the barrier multilayer film 205. Therefore, the layers are stacked so as to be in contact with the vapor deposition layer 202. The gas barrier coating film 203 is a cured film formed by a coating agent for a gas barrier coating film made of a resin composition containing a metal alkoxide, a hydroxyl group-containing water-soluble resin, and a silane coupling agent added as necessary. is there.

The mass ratio of the hydroxyl group-containing water-soluble resin / metal alkoxide in the resin composition is preferably 5/95 or more and 20/80 or less, more preferably 8/92 or more and 15/85 or less. When it is smaller than the above range, the barrier effect of the barrier coating layer tends to be insufficient, and when it is larger than the above range, the rigidity and brittleness of the barrier coating layer tend to increase.

The thickness of the gas barrier coating film 203 is preferably 100 nm or more and 800 nm or less. If it is thinner than the above range, the barrier effect of the gas barrier coating film 203 tends to be insufficient, and if it is thicker than the above range, rigidity and brittleness tend to increase.

The metal alkoxide has the general formula R ₁ nM (OR ₂ ) m (wherein R ₁ and R ₂ represent a hydrogen atom or an organic group having 1 to 8 carbon atoms, M represents a metal atom, n Represents an integer of 0 or more, m represents an integer of 1 or more, and n + m represents a valence of M. Even if each of a plurality of R ₁ and R _{2 in} one molecule is the same, (It may be different.) ... It is represented by (XI).

Specific metal atoms represented by M in the metal alkoxide include silicon, zirconium, titanium, aluminum, tin, lead, borane, and the like. For example, alkoxy in which M is Si (silicon) It is preferred to use silane.

In the general formula (XI), specific examples of OR ₂ include a hydroxyl group, a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an i-propoxy group, a butoxy group, and a 3-methacryloxy group. Examples thereof include alkoxy groups such as 3-acryloxy group and phenoxy group, and phenoxy groups.

In the above, specific examples of R ₁ include methyl group, ethyl group, n-propyl group, isopropyl group, phenyl group, p-styryl group, 3-chloropropyl group, trifluoromethyl group, vinyl group, γ-glycol. Examples thereof include a sidoxypropyl group, a methacryl group, and a γ-aminopropyl group.

Specific examples of the alkoxysilane include, for example, tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetrabutoxysilane, tetraphenoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, Methyltributoxysilane, methyltriphenoxysilane, phenylphenoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, dimethyldimethoxysilane, dimethyldiethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, isopropyltrimethoxy Silane, isopropyltriethoxysilane, dimethyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, vinyl Limethoxysilane, vinyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyl Trimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-acryloxypropyltriethoxysilane, 3-chloropropyltriethoxysilane, trifluoromethyltrimethoxysilane, 1,6- Examples include various alkoxysilanes such as bis (trimethoxysilyl) hexane and phenoxysilane. In the present embodiment, a polycondensation product of these alkoxysilanes can also be used. Specifically, for example, polytetramethoxysilane, polytetraethoxysilane, or the like can be used.

The silane coupling agent is used to adjust the crosslinking density of a cured film with a metal alkoxide and a hydroxyl group-containing water-soluble resin to obtain a film having a barrier property and a heat-resistant water treatment property.

The silane coupling agent has the general formula: R ₃ nSi (OR ₄ ) 4-n (XII)
(In the formula, R ₃ and R ₄ each independently represents an organic functional group, and n is 1 to 3.)
It is represented by

In the general formula (XII), R ₃ is, for example, a hydrocarbon group such as an alkyl group or an alkylene group, an epoxy group, a (meth) acryloxy group, a ureido group, a vinyl group, an amino group, an isocyanurate group or an isocyanate group. The functional group which has is mentioned. Specifically, at least one of R ₃ present in two or three is preferably a functional group having an epoxy group, such as a 3-glycidoxypropyl group and a 2- (3,4 epoxycyclohexyl) group. It is more preferable that R ₃ may be the same or different.

In the general formula (XII), R ₄ is, for example, an organic functional group having 1 to 8 carbon atoms, preferably an alkyl group having 1 to 8 carbon atoms which may have a branch, or 3 to 3 carbon atoms. 7 alkoxyalkyl groups. For example, examples of the alkyl group having 1 to 8 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group and the like. Examples of the alkoxyalkyl group having 3 to 7 carbon atoms include methyl ethyl ether, diethyl ether, methyl propyl ether, methyl isopropyl ether, ethyl propyl ether, ethyl isopropyl ether, methyl butyl ether, ethyl butyl ether, methyl sec-butyl ether, ethyl sec. A group obtained by removing one hydrogen atom from a linear or branched ether such as butyl ether, methyl tert-butyl ether, or ethyl tert-butyl ether; Note that (OR ₄ ) may be the same or different.

Examples of the silane coupling agent represented by the general formula (XII) include 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropyltriethoxysilane when n = 1. Examples of n = 2 include 3-glycidoxypropylmethyldimethoxysilane and 3-glycidoxypropylmethyldiethoxysilane. When n = 2, 3-glycidoxypropyldimethylmethoxysilane, 3-glycidoxypropyl Sidoxypropyldimethylethoxysilane, 2- (3,4-epoxycyclohexyl) dimethylmethoxysilane, 2- (3,4-epoxycyclohexyl) dimethylethoxysilane and the like.

In particular, the crosslinking density of the cured film of the barrier coating layer using 3-glycidoxypropylmethyldimethoxysilane and 3-glycidoxypropylmethyldiethoxysilane is lower than the crosslinking density in the system using trialkoxysilane. Become. Therefore, since it is excellent as a film having gas barrier properties and heat-resistant water treatment properties, it becomes a flexible cured film, and also has excellent bending resistance. Therefore, the packaging material using the barrier film has gas barrier properties even after the gelbo flex test. Hard to deteriorate.

Silane coupling agents with n = 1, 2, 3 can be mixed and used, and the amount ratio and amount of silane coupling agent used are determined by the design of the cured film of the barrier coating layer. .

The hydroxyl group-containing water-soluble resin can be dehydrated and co-condensed with a metal alkoxide, and the degree of saponification is preferably 90% or more and 100% or less, more preferably 95% or more and 100% or less, and 99% or more, 100 % Or less is more preferable. When the saponification degree is smaller than the above range. The hardness of the barrier coating layer tends to decrease.

Specific examples of the hydroxyl group-containing water-soluble resin include, for example, polyvinyl alcohol resins, ethylene / vinyl alcohol copolymers, polymers of bifunctional phenol compounds and bifunctional epoxy compounds, and the like. You may use, 2 or more types may be mixed and used, and you may make it copolymerize and use. Among these, polyvinyl alcohol is preferable and polyvinyl alcohol resin is preferable because it is excellent in flexibility and affinity.

Specifically, for example, a polyvinyl alcohol resin obtained by saponifying polyvinyl acetate or an ethylene / vinyl alcohol copolymer obtained by saponifying a copolymer of ethylene and vinyl acetate is used. can do.
Examples of such polyvinyl alcohol resins include PVA-124 manufactured by Kuraray Co., Ltd. (degree of saponification = 99%, degree of polymerization = 2,400), and “GOHSENOL NM-14 (degree of saponification) manufactured by Nippon Synthetic Chemical Industries = 99%, degree of polymerization = 1,400).

(Preferred configuration of barrier laminate film)
Next, a preferable configuration of the barrier laminate film 205 in the thickness direction when the vapor deposition layer 202 is a transparent vapor deposition layer containing aluminum oxide will be described with reference to FIG. FIG. 19 shows time-of-flight secondary ion mass spectrometry (TOF-) while soft etching is repeated at a constant rate on the surface of the barrier laminate film 205 on the gas barrier coating film 203 side with a Cs (cesium) ion gun. It is a figure which shows the result of having measured the ion derived from the vapor deposition layer 202 containing an aluminum oxide, and the ion derived from the base material 201 using SIMS. The vapor deposition layer 202 of the barrier laminate film 205 includes a transition region specified by the graph analysis diagram shown in FIG.

The transition region is the position of the peak of element-bonded Al ₂ O ₄ H that is converted into aluminum hydroxide and is detected by etching the barrier laminate film 205 from the gas barrier coating film 203 side using TOF-SIMS. This is a region between T ₂ and the interface T ₁ between the vapor deposition layer 202 and the substrate 201. Interface T ₁ of the the deposition layer 202 and the substrate 201, the intensity of the graph element C ₆ is identified as a position that is half the strength of the element C ₆ in the substrate 201. In FIG. 19, the symbol W ₁ represents the thickness of the transition region.

The ratio of the thickness W ₁ of the transition region to the thickness of the vapor deposition layer 202 (hereinafter also referred to as the transition region modification rate) is desirably 5% or more and 60% or less. By making the transformation rate 5% or more and 60% or less, when the packaging material including the barrier laminate film 205 is subjected to sterilization treatment such as boil treatment or retort treatment, the barrier property of the barrier laminate film 205 against water vapor is improved. It can suppress that it falls. A retort process is a process which heats a packaging bag in a pressurized state, after filling the packaging bag comprised with the packaging material provided with the barrier property laminated | multilayer film 205 and sealing a packaging bag. The temperature of retort processing is 120 degreeC or more, for example. The boil process is a process of filling the packaging bag with the contents and sealing the packaging bag, and then bathing the packaging bag under atmospheric pressure. The temperature of boil processing is 90 degreeC or more and 100 degrees C or less, for example. Note that the packaging material including the barrier laminated film 205 having a transition region transformation rate of 5% or more and 60% or less is used in packaging bags that are not subjected to sterilization treatment such as boil treatment or retort treatment. However, it can function effectively in maintaining the barrier property against gases such as oxygen and water vapor.

The interface between the base material 201 and the vapor deposition layer 202 is subjected to mechanical and chemical stress by heat. Therefore, in order to suppress deterioration in adhesion and barrier properties, it is important to firmly cover the base material 201 with the vapor deposition layer 202 at the interface between the base material 201 and the vapor deposition layer 202.

Aluminum hydroxide has good adhesion to plastic films such as polyester film due to its chemical structure, and has high water vapor barrier properties because it itself forms a network and is dense. However, the bonding structure based on hydrogen bonding between aluminum hydroxide and the plastic film is easily broken microscopically against heat stress. Also, it easily penetrates into the membrane due to the affinity of the water molecule and aluminum hydroxide grain interface to the aluminum hydroxide network.

In the present embodiment, in order to make the transition region at the interface with the base material 201 formed by aluminum hydroxide in the vapor deposition layer 202 containing aluminum oxide as much as possible, attention is paid to element-bonded Al ₂ O ₄ H and its presence. Control the amount. This suppresses aluminum hydroxide generated from elementally bonded Al ₂ O ₄ H due to thermal stress, and increases the proportion of the aluminum oxide layer that is relatively low in aluminum hydroxide, thereby making it microscopic due to water molecules caused by thermal stress. It is intended to suppress the destruction of the vapor deposition layer 202 and the interface destruction with the plastic film. As a result, a barrier laminate film 205 having unprecedented adhesion and barrier properties can be provided.

The vapor deposition layer 202 containing aluminum oxide can be formed by forming the vapor deposition layer 202 on the surface of the base material 201 that has been pretreated with oxygen plasma. As a vapor deposition method for forming the vapor deposition layer 202, various vapor deposition methods can be applied among physical vapor deposition and chemical vapor deposition. The physical vapor deposition method can be selected from the group consisting of vapor deposition method, sputtering method, ion plating method, ion beam assist method, and cluster ion beam method. Chemical vapor deposition methods include plasma CVD method, plasma polymerization method, thermal method. It can be selected from the group consisting of CVD method and catalytic reaction type CVD method. In this embodiment, a physical vapor deposition method is preferable.

A specific example of a method for obtaining the graph of FIG. 19 will be described. First, using Cs, etching is performed from the outermost surface of the gas barrier coating film 203, and the element bonding of the interface between the gas barrier coating film 203, the vapor deposition layer 202, and the film such as the substrate 201 and the element bonding of the vapor deposition layer 202 are performed. Perform analysis. Thereby, the graph shown in FIG. 19 can be obtained.

Next, a specific example of the analysis method of the graph in FIG. 19 will be described. Here, a case where the gas barrier coating film 203 contains silicon oxide will be described.

First, in the graph, the position at which the strength of SiO ₂ (mass number 59.96), which is a constituent element of the gas barrier coating film 203, becomes half the strength of the gas barrier coating film 203 is indicated by the gas barrier coating film 203 and the vapor deposition layer. 202 is specified as the interface. Next, a position where the strength of C ₆ (mass number 72.00), which is a constituent material of the base material 201, becomes half of the strength of the base material 201 is specified as an interface between the base material 201 and the vapor deposition layer 202. Further, the distance in the thickness direction between the two interfaces is adopted as the thickness of the vapor deposition layer 202.

Next, a peak of the measured element-bonded Al ₂ O ₄ H (mass number 118.93) is obtained, and the transition from the peak to the interface is taken as the transition region. However, when the component of the gas barrier coating film 203 is made of a material having the same mass number as Al ₂ O ₄ H (mass number 118.93), it is necessary to separate the waveform of 118.93.

When reactants AlSiO ₄ and hydroxide Al ₂ O ₄ H are generated at the interface between the gas barrier coating film 203 and the vapor deposition layer 202, Al and the Al present at the interface between the substrate 201 and the vapor deposition layer 202 are present. ₂ O ₄ H can be separated. As described above, the waveform separation can be appropriately handled according to the material of the gas barrier coating film 203.

In waveform separation, for example, a profile with a mass number of 118.93 obtained by TOF-SIMS is subjected to nonlinear curve fitting using a Gaussian function, and overlapping peaks are separated using a least square method Levenberg Marquardt algorithm. It can be carried out.

The above analysis assumes that the barrier laminate film 205 includes the base material 201, the vapor deposition layer 202, and the gas barrier coating film 203. However, the same analysis shows that the barrier laminate film 205 includes the base material 201. In addition, the present invention can also be applied to the case where the vapor barrier layer 202 is included but the gas barrier coating film 203 is not included. Even when the barrier laminate film 205 does not include the gas barrier coating film 203, the packaging material including the barrier laminate film 205 can be boiled by setting the transformation rate of the transition region of the vapor deposition layer 202 within a predetermined range. When the sterilization process such as the process or the retort process is performed, it is possible to prevent the barrier property of the barrier laminate film 205 from being deteriorated against water vapor. When the barrier laminate film 205 includes a base material 201 and a vapor deposition layer 202 and etching is performed from the vapor deposition layer 202 side using time-of-flight secondary ion mass spectrometry (TOF-SIMS), the transition region of the vapor deposition layer 202 is changed. The modification rate is preferably 45% or less.

Next, mechanical properties of the barrier laminate film 205 will be described. The mechanical properties of the barrier laminate film 205 are mainly determined by the mechanical properties of the substrate 201. Therefore, the mechanical properties such as the loop stiffness, puncture strength, tensile strength, tensile elongation, tensile strength divided by tensile elongation, thermal shrinkage rate, and tensile elastic modulus of the barrier laminate film 205 are the same as those of the substrate 201. This is equivalent to the mechanical properties of the high-stiffness PET film and PBT film to be constructed. Therefore, if the measurement results of the mechanical properties of the barrier laminate film 205 are within the above-described preferable range, the measurement results of the mechanical properties of the base material 201 formed of a high stiffness PET film or a PBT film are also described above. Is considered to be within the preferable range.

[Sealant layer]
Next, the sealant layer 212 will be described. The sealant layer 212 is a layer containing a thermoplastic resin that constitutes the inner surface 210 x of the packaging material 210. In the example shown in FIGS. 16 and 17, the sealant layer 212 is formed by bonding a thermoplastic resin film to the barrier laminate film 205 via the first adhesive layer 213. Although not shown, the sealant layer 212 may be formed by extruding a thermoplastic resin onto the barrier laminate film 205.

As a material constituting the sealant layer 212, one or more resins selected from polyethylene such as low density polyethylene and linear low density polyethylene, and polypropylene can be used. The sealant layer 212 may be a single layer or a multilayer. The sealant layer 212 is preferably made of an unstretched film. “Unstretched” is a concept that includes not only a film that is not stretched at all, but also a film that is slightly stretched due to the tension applied during film formation.

By the way, the packaging container constituted by the packaging material 210 including the sealant layer 212 may be subjected to sterilization treatment such as boil treatment and retort treatment at a high temperature. Accordingly, the sealant layer 212 has a heat resistance that can withstand the processing at these high temperatures.

The melting point of the material constituting the sealant layer 212 is preferably 150 ° C. or higher, and more preferably 160 ° C. or higher. By increasing the melting point of the sealant layer 212, the packaging container can be retorted at a high temperature, and the time required for the retorting process can be shortened. Note that the melting point of the material constituting the sealant layer 212 is lower than the melting point of the resin constituting the substrate 201.

When considering from the viewpoint of the retort treatment, a material mainly composed of propylene can be used as a material constituting the sealant layer 212 as in the case of the sealant layer 70 in the first embodiment.

Further, when considering from the viewpoint of boil processing, examples of the material constituting the sealant layer 212 include polyethylene, polypropylene, or a combination thereof as in the case of the sealant layer 70 in the first embodiment described above. Can do.

Preferably, the sealant layer 212 includes a propylene / ethylene block copolymer as in the case of the sealant layer 70 in the first embodiment described above. For example, the sealant film including the sealant layer 212 is an unstretched film having a propylene / ethylene block copolymer as a main component. By using the propylene / ethylene block copolymer, the impact resistance of the sealant film can be increased, and thereby the packaging container can be prevented from being broken due to the impact at the time of dropping. Moreover, the puncture resistance of the packaging material 210 can be improved.

Further, the sealant layer 212 may further include a thermoplastic elastomer as in the case of the sealant layer 70 in the first embodiment described above. By using a thermoplastic elastomer, the impact resistance and puncture resistance of the sealant film can be further enhanced.

The content of the propylene / ethylene block copolymer in the sealant layer 212 is, for example, 80% by mass or more, and preferably 90% by mass or more.

Examples of the method for producing a propylene / ethylene block copolymer include a method of polymerizing propylene, ethylene, and the like as raw materials using a catalyst. As the catalyst, Ziegler-Natta type or metallocene catalyst can be used.

The sealant layer 212 may have an easy peel property. The easy peel property means that, for example, when a packaging material 210 having a sealant layer 212 is used to form a lid for a container, the lid is easily peeled from the flange portion of the container at the lower surface thereof, that is, the sealant layer 212. It is a characteristic. The easy peel property can be expressed, for example, by configuring the sealant layer 212 with two or more types of resins and making one resin and another resin incompatible. Examples of the resin capable of exhibiting easy peel properties include a mixed resin of polyethylene and polypropylene such as high-density polyethylene.

When the sealant layer 212 has an easy peel property, the sealant layer 212 may include a first layer 2121 and a second layer 2122 as shown in FIG. In this case, the first layer 2121 may be a layer containing mixed polypropylene and high density polyethylene. The second layer 2122 may be a layer made of polypropylene or high-density polyethylene. Such a sealant layer 212 can be formed by bonding a coextruded film including the first layer 2121 and the second layer 2122 to the barrier laminate film 205. When the second layer 2122 is made of polypropylene, the sealant layer 212 including the first layer 2121 and the second layer 2122 has heat resistance that can withstand heat treatment up to 135 ° C., for example. When the second layer 2122 is made of high-density polyethylene, the sealant layer 212 including the first layer 2121 and the second layer 2122 has heat resistance that can withstand heat treatment up to 123 ° C., for example.

The sealant layer 212 may contain a biomass-derived component or may not contain a biomass-derived component. When the sealant layer 212 is formed of a material containing a biomass-derived component, the sealant layer 212 can be formed using the following biomass polyolefin. Moreover, when forming the sealant layer 212 with the material which does not contain a biomass origin component, the sealant layer 212 can be formed using the conventionally well-known thermoplastic resin derived from a fossil fuel. Similarly, the sealant layer 70 in the first embodiment described above may include a biomass-derived component described later, or may not include a biomass-derived component.

Biomass polyolefin is a polymer of a monomer containing an olefin such as ethylene derived from biomass. Since a biomass-derived olefin is used as a monomer as a raw material, the polymerized polyolefin is derived from biomass. In addition, the raw material monomer of polyolefin does not need to contain 100 mass% of olefin derived from biomass.

For example, biomass-derived ethylene can be produced using biomass-derived ethanol as a raw material. In particular, it is preferable to use biomass-derived fermented ethanol obtained from plant raw materials. A plant raw material is not specifically limited, A conventionally well-known plant can be used. For example, corn, sugar cane, beet, and manioc can be mentioned.

Biomass-derived fermented ethanol refers to ethanol that has been purified after contacting a microorganism-producing product or a product derived from its crushed material with a culture solution containing a carbon source obtained from plant raw materials. For the purification of ethanol from the culture solution, conventionally known methods such as distillation, membrane separation, and extraction can be applied. For example, a method of adding benzene, cyclohexane or the like and azeotropically or removing water by membrane separation or the like can be mentioned.

The monomer that is a raw material of biomass polyolefin may further contain an ethylene monomer derived from fossil fuel and / or an α-olefin monomer derived from fossil fuel, or may further include an α-olefin monomer derived from biomass.

The above α-olefin is not particularly limited in carbon number, but usually those having 3 to 20 carbon atoms can be used, and is preferably butylene, hexene or octene. This is because if it is butylene, hexene or octene, it can be produced by polymerization of ethylene which is a biomass-derived raw material. In addition, by including such an α-olefin, the polymerized polyolefin has an alkyl group as a branched structure, so that it can be more flexible than a simple linear one.

As the biomass polyolefin, polyethylene or a copolymer of ethylene and α-olefin may be used alone, or two or more kinds may be mixed and used. In particular, the biomass polyolefin is preferably polyethylene. This is because, by using ethylene, which is a biomass-derived raw material, it is theoretically possible to manufacture with 100% biomass-derived components.

The biomass polyolefin may contain two or more kinds of biomass polyolefins having different biomass degrees, and the biomass degree of the polyolefin resin layer as long as it is within the range described later.

Biomass polyolefin, preferably 0.91 g / cm ³ or more 0.93 g / cm ³ or less, more preferably 0.912 g / cm ³ or more 0.928 g / cm ³ or less, more preferably 0.915 g / cm ³ or more 0 It has a density of 925 g / cm ³ or less. The density of biomass polyolefin is a value measured according to the method defined in Method A of JIS K7112-1980 after annealing described in JIS K6760-1995. If the density of the biomass polyolefin is 0.91 g / cm ³ or more, the rigidity of the polyolefin resin layer containing the biomass polyolefin can be increased, and it can be suitably used as the inner layer of the packaged product. Moreover, if the density of biomass polyolefin is 0.93 g / cm < ³ > or less, the transparency and mechanical strength of the polyolefin resin layer containing biomass polyolefin can be improved, and it can be used suitably as an inner layer of a packaged product.

Biomass polyolefin has a melt flow of 0.1 g / 10 min to 10 g / 10 min, preferably 0.2 g / 10 min to 9 g / 10 min, more preferably 1 g / 10 min to 8.5 g / 10 min. It has a rate (MFR). The melt flow rate is a value measured by the method A under the conditions of a temperature of 190 ° C. and a load of 21.18 N in the method specified in JIS K7210-1995. If the MFR of the biomass polyolefin is 0.1 g / 10 min or more, the extrusion load during the molding process can be reduced. Moreover, if MFR of biomass polyolefin is 10 g / 10min or less, the mechanical strength of the polyolefin resin layer containing biomass polyolefin can be raised.

As biomass polyolefin suitably used, low density polyethylene derived from biomass (trade name: SBC818, density: 0.918 g / cm ³ , MFR: 8.1 g / 10 min, biomass degree 95%) manufactured by Braskem, Low-density polyethylene derived from biomass manufactured by Braskem (trade name: SPB681, density: 0.922 g / cm ³ , MFR: 3.8 g / 10 min, biomass degree 95%), linear derived from biomass manufactured by Braskem Examples thereof include low-density polyethylene (trade name: SLL118, density: 0.916 g / cm ³ , MFR: 1.0 g / 10 min, biomass degree 87%).

Examples of the fossil fuel-derived thermoplastic resin include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, polypropylene, propylene-ethylene copolymer, ethylene-vinyl acetate copolymer, Examples thereof include an ethylene-acrylic acid copolymer, an ethylene-methacrylic acid copolymer, an ethylene-methyl acrylate copolymer, an ethylene-ethyl acrylate copolymer, an ethylene-methyl methacrylate copolymer, and an ionomer.

The sealant layer 212 has a biomass degree of preferably 5% or more, more preferably 5% or more and 60% or less, and still more preferably 10% or more and 60% or less. If the degree of biomass is in the above range, the amount of fossil fuel used can be reduced, and the environmental load can be reduced.

As described above, the sealant layer 212 may be a single layer or a multilayer. When using the biomass polyolefin as described above for the sealant layer, a sealant layer including three layers of an inner layer, an intermediate layer, and an outer layer may be used. In that case, the intermediate layer may be a layer made of biomass polyolefin, or a layer made of a mixture of biomass polyolefin and a conventionally known fossil fuel-derived polyolefin, and the inner layer and the outer layer may be a conventionally known fossil fuel-derived polyolefin. preferable.

The thickness of the sealant layer 212 is preferably 30 μm or more, more preferably 40 μm or more. The thickness of the sealant layer 212 is preferably 100 μm or less, and more preferably 80 μm or less.

[Adhesive layer]
The first adhesive layer 213 is a layer that adheres the barrier laminate film 205 and the film including the sealant layer 212. The first adhesive layer 213 is an adhesive layer or an adhesive resin layer. Hereinafter, each of the adhesive layer and the adhesive resin layer will be described.

The adhesive layer can be formed by a conventionally known method such as a dry laminating method. When two layers are bonded by a dry laminating method, the adhesive layer is formed by applying an adhesive to the surface of the layer to be laminated and drying it. Examples of the adhesive to be applied include one-part or two-part cured or non-cured vinyl, (meth) acrylic, polyamide, polyester, polyether, polyurethane, epoxy, and rubber. It is possible to use an adhesive such as a solvent type, an aqueous type, or an emulsion type. As a two-component curable adhesive, a cured product of a polyol and an isocyanate compound can be used. As a coating method of the adhesive for laminating, for example, direct gravure roll coating method, gravure roll coating method, kiss coating method, reverse roll coating method, fountain method, transfer roll coating method, and other methods can be used. . The adhesive layer after drying has a thickness of, for example, 1 μm to 10 μm, preferably 2 μm to 5 μm.

The adhesive layer may contain a biomass-derived component. For example, when the adhesive layer includes a cured product of a polyol and an isocyanate compound, at least one of the polyol and the isocyanate compound may include a biomass-derived component. Thereby, the biomass degree of the packaging material 210 can further be improved.

The adhesive resin layer contains a thermoplastic resin. The adhesive resin layer can be formed by a conventionally known method such as a melt extrusion laminating method or a sand laminating method. Examples of the thermoplastic resin that can be used for the adhesive resin layer include a polyethylene resin, a polypropylene resin, or a cyclic polyolefin resin, or a copolymer resin, a modified resin, or a mixture (including alloy) containing these resins as a main component. ) Can be used. Examples of polyolefin resins include low density polyethylene (LDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE), linear (linear) low density polyethylene (LLDPE), polypropylene (PP), and metallocene catalysts. Ethylene-α-olefin copolymer, ethylene-polypropylene random or block copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-acrylic acid copolymer (EAA), ethylene Ethyl acrylate copolymer (EEA), ethylene-methacrylic acid copolymer (EMAA), ethylene-methyl methacrylate copolymer (EMMA), ethylene / maleic acid copolymer, ionomer resin, and interlayer adhesion In order to improve the , It can be used acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, and an acid-modified polyolefin resin modified with an unsaturated carboxylic acid such as itaconic acid. Further, a resin obtained by graft polymerization or copolymerization of an unsaturated carboxylic acid, an unsaturated carboxylic acid anhydride, or an ester monomer can be used as the polyolefin resin. These materials can be used alone or in combination of two or more. As the cyclic polyolefin-based resin, for example, cyclic polyolefins such as ethylene-propylene copolymer, polymethylpentene, polybutene, and polynorbornene can be used. These resins can be used alone or in combination. The adhesive resin layer has a thickness of, for example, 5 μm to 50 μm, preferably 10 μm to 30 μm.

In addition, as the above-described polyethylene-based resin, those using ethylene derived from biomass described in the sealant layer 212 as a monomer unit may be used. Thereby, the biomass degree of the packaging material 210 can further be improved.

[Print layer]
The printed layer 218 is designed to display letters, numbers, patterns, graphics, symbols, etc. for decoration, display of contents and packaged products, display of the best-before period, display of manufacturers, sellers, etc. , A layer for forming a desired arbitrary printed pattern such as a pattern. The printing layer 218 can be provided as necessary, and can be provided on the barrier laminate film 205, for example. The printing layer 218 may be provided on the entire surface of the film or may be provided on a part thereof. The printing layer 218 can be formed using a conventionally known pigment or dye, and the formation method is not particularly limited.

The printing layer 218 preferably has a thickness of 0.1 μm to 10 μm, more preferably 1 μm to 5 μm, and still more preferably 1 μm to 3 μm.

The printing layer 218 may contain a biomass-derived component. For example, when the printing layer 218 includes a cured product of a polyol and an isocyanate compound, at least one of the polyol and the isocyanate compound may include a biomass-derived component.

<Method for manufacturing packaging material>
Next, an example of a method for manufacturing the packaging material 210 will be described. First, an example of a method for producing the barrier laminate film 205 will be described.

(Manufacturing process of barrier laminated film)
First, the base material 201 is prepared. Subsequently, a vapor deposition layer 202 containing aluminum oxide is formed on the surface of the substrate 201. FIG. 20 is a diagram illustrating an example of the film forming apparatus 260. Hereinafter, a film forming apparatus 260 and a film forming method using the film forming apparatus 260 will be described.

As shown in FIG. 20, in the film forming apparatus 260, partition walls 285a to 285c are formed in the decompression chamber 262. The partition walls 285a to 285c form a base material transfer chamber 262A, a plasma pretreatment chamber 262B, and a film formation chamber 262C, and in particular, a plasma pretreatment chamber 262B and a film formation chamber as spaces surrounded by the partition walls and the partition walls 285a to 285c. 262C is formed, and an exhaust chamber is further formed inside each chamber as necessary.

The plasma pretreatment process in the plasma pretreatment chamber 262B and the plasma pretreatment chamber 262B will be described. In the plasma pretreatment chamber 262B, a part of the plasma pretreatment roller 270 that conveys the substrate 201 to be pretreated and enables the plasma treatment is provided so as to be exposed to the substrate conveyance chamber 262A. Yes. The substrate 201 moves to the plasma pretreatment chamber 262B while being wound up.

The plasma pretreatment chamber 262B and the film formation chamber 262C are provided in contact with the base material transfer chamber 262A, and can move without the base material 201 being exposed to the atmosphere. Further, the pretreatment chamber 262B and the base material transfer chamber 262A are connected by a rectangular hole, and a part of the plasma pretreatment roller 270 protrudes to the base material transfer chamber 262A side through the rectangular hole. A gap is opened between the wall of the transfer chamber and the pretreatment roller 270, and the substrate 201 can move from the substrate transfer chamber 262A to the film forming chamber 262C through the gap. The structure between the base material transfer chamber 262A and the film formation chamber 262C is similar, and the base material 201 can be moved without being exposed to the atmosphere.

The base material transport chamber 262A is moved again to the base material transport chamber 212A by the film forming roller 275, and the base material 201 with the vapor deposition layer 202 formed on one side is wound up in a roll shape. A take-up roller is provided so that the substrate 201 on which the vapor deposition layer 202 is formed can be taken up.

When manufacturing the barrier laminate film 205 having the vapor deposition layer 202 containing aluminum oxide, the plasma pretreatment chamber 262B separates the space where the plasma is generated from other regions so that the facing space can be efficiently evacuated. By being configured, control of the plasma gas concentration becomes easy and productivity is improved. The pre-treatment pressure formed by reducing the pressure can be set and maintained at about 0.1 Pa to 100 Pa. In particular, the oxygen plasma pre-treatment is performed in order to obtain a preferable transformation rate of the transition region of the vapor deposition layer 202 containing aluminum oxide. The processing pressure is preferably 1 to 20 Pa.

The conveying speed of the substrate 201 is not particularly limited, but can be at least 200 to 1000 m / min from the viewpoint of production efficiency, and in particular, oxygen in order to obtain a transformation rate in the transition region of the vapor deposition layer 202 containing aluminum oxide. The conveyance speed of the plasma pretreatment is preferably 300 to 800 m / min.

The plasma pretreatment roller 270 constituting the plasma pretreatment apparatus prevents the base material 201 from being contracted or damaged by heat during the plasma processing by the plasma pretreatment means, and the oxygen plasma P is uniformly and widely distributed over the base material 201. It is intended to be applied to. It is preferable that the pretreatment roller 270 can be adjusted to a constant temperature between −20 ° C. and 100 ° C. by adjusting the temperature of the temperature adjustment medium circulating in the pretreatment roller.

The plasma pretreatment means includes a plasma supply means and a magnetic formation means. The plasma pretreatment means cooperates with the plasma pretreatment roller 270 to confine the oxygen plasma P in the vicinity of the surface of the substrate 201.

The plasma pretreatment means is provided so as to cover a part of the pretreatment roller 270. Specifically, the plasma supply means 272 and the magnetic formation means 273 that constitute the plasma pretreatment means are disposed along the surface in the vicinity of the outer periphery of the pretreatment roller 270. The plasma supply means 272 includes a plasma supply nozzle that supplies a plasma source gas. The magnetic forming means 273 has a magnet or the like for promoting the generation of the plasma P. Further, the plasma pretreatment means includes an electrode 271 to which a voltage is applied between the plasma pretreatment means 270 and the pretreatment roller 270. FIG. 20 shows an example in which the electrode 271 and the plasma supply means 272 are separate members, but the present invention is not limited to this. Although not shown, the electrode 271 and the plasma supply means 272 may be constituted by an integral member.

Plasma P is generated in a space sandwiched between the pretreatment roller 270 and the magnetic forming means 273, and a region having a high plasma density is formed in the vicinity of the surface of the pretreatment roller 270 and the substrate 201. The plasma-treated surface can be formed by performing oxygen plasma pretreatment on the inner surface.

The plasma supply means 272 of the plasma pretreatment means includes a source gas volatilization supply device 268 connected to a plasma supply nozzle provided outside the decompression chamber 262 and a source gas supply line for supplying source gas from the device. The plasma source gas to be supplied is supplied while oxygen alone or a mixed gas of oxygen gas and inert gas is measured from the gas reservoir through a flow rate controller while measuring the gas flow rate. As an inert gas, 1 type, or 2 or more types of mixed gas chosen from the group which consists of argon, helium, and nitrogen is mentioned.

These supplied gases are mixed at a predetermined ratio as necessary, formed into a plasma raw material gas alone or a plasma forming mixed gas, and supplied to the plasma supply means. The single or mixed gas is supplied to the plasma supply nozzle of the plasma supply means, and is supplied to the vicinity of the outer periphery of the pretreatment roller 270 where the supply port of the plasma supply nozzle opens. The nozzle opening is directed to the base material 201 on the pretreatment roller 270, and is arranged and configured so that the oxygen plasma P can be uniformly diffused and supplied to the entire surface of the base material 201. Thereby, a uniform plasma pretreatment can be performed on a large area portion of the substrate 201.

As described above, the transition rate of the transition region of the vapor deposition layer 202 containing aluminum oxide is set to 5% or more and 60% or less. The active gas) is preferably 6/1 to 1/1, more preferably 5/2 to 3/2. By setting the mixing ratio to 6/1 to 1/1, the film formation energy of the vapor deposition layer 202 on the substrate 201 is increased, and by setting the mixing ratio to 5/2 to 3/2, the formation of aluminum hydroxide is increased. Is formed in the vicinity of the interface of the base material, that is, the rate of transformation of the transition region is lowered.

The electrode 271 functions as a counter electrode of the pretreatment roller 270. The plasma source gas supplied by the potential difference due to the high frequency voltage, the low frequency voltage, etc. supplied to the pretreatment roller 270 is excited, and plasma P is generated and supplied.

Specifically, the electrode 271 is provided with a plasma pretreatment roller as a plasma power source, an AC voltage having a frequency of 10 Hz to 2.5 GHz is applied between the electrode 271 and the counter electrode, and input power control or impedance control is performed. In addition, an arbitrary voltage can be applied between the plasma pretreatment roller 270 and the plasma pretreatment roller 270. The film forming apparatus 260 includes a power source 282 capable of applying a bias voltage that makes the oxygen plasma P capable of physically or chemically modifying the surface properties of the substrate 201 positive.

The plasma intensity per unit area is preferably 50 to 8000 W · sec / m ² . At 50 W · sec / m ² or less, the effect of the plasma pretreatment is not observed, and at 8000 W · sec / m ² or more, deterioration of the base material 201 due to plasma occurs, such as consumption of the base material 201, damage coloring, and firing. There is a tendency. In particular, the plasma intensity per unit area is preferably 100 to 1000 W · sec / m ² . By providing the plasma intensity with a bias voltage perpendicular to the base material 201, adhesion to the vapor deposition layer 202 containing aluminum oxide can be improved stably.

As the magnetic forming means 273, an insulating spacer and a base plate provided in a magnet case and a magnet provided on the base plate can be used. An insulating shield plate is provided on the magnet case, and an electrode can be attached to the insulating shield plate. The magnet case and the electrode are electrically insulated, and even if the magnet case is installed and fixed in the decompression chamber 262, the electrode can be brought to an electrically floating level. By providing the magnet, the reactivity in the vicinity of the surface of the substrate 201 is increased, and a good plasma pretreatment surface can be formed at a high speed.

Preferably, the magnet is configured such that the magnetic flux density at the surface position of the substrate 201 is from 10 gauss to 10,000 gauss. If the magnetic flux density on the surface of the substrate 201 is 10 gauss or more, the reactivity in the vicinity of the surface of the substrate 201 can be sufficiently increased, and a good pretreatment surface can be formed at high speed.

Next, a film formation process in the film formation chamber 262C and the film formation chamber 262C will be described. The film forming apparatus 260 includes a film forming roller 275 disposed in the decompressed film forming chamber 262 </ b> C, and a target of the vapor deposition film forming unit 274 disposed to face the film forming roller 275. The film forming roller 275 conveys the base material 201 while winding the base material 201 with the processing surface of the base material 201 preprocessed by the plasma pretreatment apparatus facing outside. In the film forming step, the target of the vapor deposition film forming means 274 is evaporated to form an aluminum oxide film on the surface of the substrate 201.

The vapor deposition film forming means 274 is, for example, a resistance heating method, and uses aluminum metal wire with aluminum as an evaporation source, and supplies aluminum to oxidize aluminum vapor while containing aluminum oxide on the surface of the substrate 201. The vapor deposition layer 202 is formed.

The thickness of the vapor deposition layer 202 containing aluminum oxide formed as described above is preferably 3 to 50 nm, more preferably 9 to 30 nm. Within this range, the barrier property can be maintained. However, when the vapor deposition layer 202 containing aluminum oxide is very thin, it is difficult to calculate the transition region transformation rate by TOF-SIMS measurement.

Next, a method for forming the gas barrier coating film 203 on the vapor deposition layer 202 will be described. First, an organic solvent such as the above metal alkoxide, silane coupling agent, hydroxyl group-containing water-soluble resin, reaction accelerator (sol-gel method catalyst, acid, etc.), water as a solvent, alcohol such as methyl alcohol, ethyl alcohol, isopropanol, etc. By mixing, a coating agent for a gas barrier coating film made of a resin composition is prepared.

When the gas barrier coating film 203 contains a silane coupling agent, a coating agent for the gas barrier coating film may be prepared as follows. First, a metal alkoxide such as alkoxysilane and a silane coupling agent are mixed. The metal alkoxide and the silane coupling agent are preferably mixed at 10 ° C. or lower. Thereby, the film structure in the gas barrier coating film 203 to be formed is likely to be dense. Subsequently, a mixture of a metal alkoxide and a silane coupling agent and a hydroxyl group-containing water-soluble resin such as a polyvinyl alcohol-based resin are mixed.

After preparing the coating agent for the gas barrier coating film, the coating agent for the gas barrier coating film is applied onto the vapor deposition layer 202 by a conventional method and dried. By this drying step, the condensation or co-condensation reaction further proceeds to form a coating film. On the first coating film, the above coating operation may be further repeated to form a plurality of coating films composed of two or more layers.

Furthermore, heat treatment is performed for 3 seconds to 10 minutes at a temperature in the range of 20 to 200 ° C., preferably 50 to 180 ° C., and a temperature below the softening point of the resin constituting the substrate 201. As a result, the gas barrier coating film 203 made of the gas barrier coating film coating agent can be formed on the vapor deposition layer 202. In this way, the barrier laminate film 205 having the substrate 201, the vapor deposition layer 202, and the gas barrier coating film 203 can be produced.

(Lamination process)
Next, a method for manufacturing the above-described packaging material 210 by laminating the sealant layer 212 on the barrier laminate film 205 will be described.

First, a barrier laminate film 205 is prepared, and a printing layer 218 is formed on the gas barrier coating film 203 of the barrier laminate film 205 by, for example, a gravure printing method. In addition, a film constituting the sealant layer 212 is prepared. Thereafter, the film including the barrier laminate film 205 and the film constituting the sealant layer 212 are bonded via a first adhesive layer 213 formed of an adhesive layer by a dry laminating method. In this way, the packaging material 210 can be obtained.

<Packaging products>
As an example of the packaged product formed by using the packaging material 210, as in the case of the first embodiment described above, the bag 10 shown in FIGS. 1, 13, and 14 is shown in FIGS. 15A and 15B. The lid material 114 of the container 110 with a lid shown can be mentioned.

For the bag of the packaging product, the packaging material 210 is folded in half, or two packaging materials 210 are prepared, and the sealant layer 212 of the front side packaging material 210 and the sealant layer 212 of the back side packaging material 210 are opposed to each other. Overlap, and the peripheral edge, for example, side seal type, two-side seal type, three-side seal type, four-side seal type, envelope-attached seal type, joint-attached seal type (pillow seal type), pleated seal type, flat bottom Various types of packaging bags can be manufactured by heat sealing using a heat sealing mode such as a sealing type or a square bottom sealing type. Further, a gusset-type packaging bag can be manufactured by performing heat sealing with the folded packaging material 210 inserted between the front packaging material 210 and the back packaging material 210. In addition, all of the packaging material 210 which comprises a packaging bag may not be the packaging material 210 by this invention. That is, at least a part of the packaging material 210 constituting the packaging bag may be the packaging material 210 including the barrier laminate film 205 having the base material 201 including the high stiffness PET film or the PBT film, and the packaging constituting the packaging bag. The other part of the material 210 may be the packaging material 210 that does not include the barrier laminate film 205.

As a heat sealing method, for example, a known method such as a bar seal, a rotary roll seal, a belt seal, an impulse seal, a high frequency seal, or an ultrasonic seal can be used.

At least one of the films such as the front film 14, the back film 15, and the lower film 16 constituting the bag 10 as shown in FIGS. 1, 13, and 14 is a base material including a high stiffness PET film or a PBT film. It is comprised by the packaging material 210 provided with the barriering laminated film 205 which has 201. FIG. Thereby, gas barrier properties and strength can be imparted to the bag 10. Similarly, the lid member 114 constituting the container with lid 110 as shown in FIGS. 15A and 15B is constituted by a packaging material 210 including a barrier laminate film 205 having a base 201 containing a high-stiffness PET film or a PBT film. You can also Thereby, gas barrier property and intensity | strength can be provided to a container with a lid | cover.

Next, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the description of the following examples unless it exceeds the gist.

The puncture strength, tearability and heat resistance of the packaging material 30 in the present invention were evaluated according to Examples A1 to A5 and Comparative Examples A1 to A2.

(Example A1)
As the stretched plastic film 60, a high stiffness polyester film (hereinafter also referred to as a high stiffness PET film) made of PET having a loop stiffness of 0.0017 N or more was prepared. Subsequently, a printed layer 36 having a thickness of 1 μm was formed on the surface of the high stiffness PET film.
Specifically, XP-55 manufactured by Toray Industries, Inc. was used as the high stiffness PET film. The thickness of the high stiffness PET film was 16 μm. The measured value of the loop stiffness of the high stiffness PET film was 0.0021 N in both the flow direction and the vertical direction. Moreover, the tensile elasticity modulus of the high stiffness PET film in the flow direction was 4.8 GPa, and the tensile elasticity modulus of the high stiffness polyester film in the vertical direction was 4.7 GPa.
The tensile strength of the high stiffness PET film in the flow direction was 292 MPa, and the tensile strength of the high stiffness polyester film in the vertical direction was 257 MPa. Further, the tensile elongation of the high stiffness PET film in the flow direction was 107%, and the tensile elongation of the high stiffness polyester film in the vertical direction was 102%. In this case, the value obtained by dividing the tensile strength of the high stiffness PET film in the flow direction by the tensile elongation is 2.73 [MPa /%], and the tensile strength of the high stiffness PET film in the vertical direction is divided by the tensile elongation. The value is 2.52 [MPa /%].
In addition, the thermal shrinkage rate of the high stiffness PET film in the flow direction and the vertical direction was both 0.4%.

Also, as the sealant layer 70, an unstretched polypropylene film ZK500 manufactured by Toray Film Processing Co., Ltd. was prepared. ZK500 contains the above-mentioned propylene / ethylene block copolymer and elastomer. The thickness of the sealant layer 70 was 60 μm.

ZK500 has a higher tensile elongation than a general unstretched polypropylene film. Specifically, the tensile elongation of ZK500 in the flow direction (MD) is 1180% when the thickness is 50 μm and 1100% when the thickness is 60 μm. The tensile elongation of ZK500 in the vertical direction (TD) is 1240% when the thickness is 50 μm, and 1150% when the thickness is 60 μm. Therefore, the product of the tensile elongation (%) and the thickness (μm) of ZK500 in the flow direction is 59000 when the thickness is 50 μm and 66000 when the thickness is 60 μm. The product of the tensile elongation (%) and thickness (μm) of ZK500 in the vertical direction is 62000 when the thickness is 50 μm and 69000 when the thickness is 60 μm.

Further, ZK500 has a lower tensile elastic modulus than a general unstretched polypropylene film. Specifically, the tensile modulus of elasticity of ZK500 in the flow direction (MD) is 640 MPa when the thickness is 50 μm, and 550 MPa when the thickness is 60 μm. The tensile modulus of elasticity of ZK500 in the vertical direction (TD) is 480 MPa when the thickness is 50 μm, and 400 MPa when the thickness is 60 μm. Therefore, the product of the tensile modulus (MPa) and the thickness (μm) of ZK500 in the flow direction is 32000 when the thickness is 50 μm and 33000 when the thickness is 60 μm. The product of the tensile modulus (MPa) and thickness (μm) of ZK500 in the vertical direction is 24000 when the thickness is 50 μm and 35000 when the thickness is 60 μm.

Subsequently, the stretched plastic film 60 and the sealant layer 70 were laminated by a dry laminating method to produce the packaging material 30. The print layer 36 was laminated so as to face the surface side of the sealant layer 70. As the adhesive layer 65, a two-component polyurethane adhesive (main agent: RU-40, curing agent: H-4) manufactured by Rock Paint Co., Ltd. was used. The main agent, RU-40, is a polyester polyol. The thickness of the adhesive layer 65 was 3.5 μm. The total thickness of the packaging material 30 was 80.5 μm.

[Evaluation of puncture resistance]
Subsequently, the piercing strength of the packaging material 30 was measured according to JIS Z1707 7.4. As a measuring instrument, Tensilon universal material testing machine RTC-1310 manufactured by A & D was used. Specifically, as shown in FIG. 21, a semicircular needle 90 having a diameter of 1.0 mm and a tip shape radius of 0.5 mm from the outer surface 30y side with respect to the test piece of the packaging material 30 in a fixed state. Was pierced at a speed of 50 mm / min (50 mm per minute), and the maximum value of stress until the needle 90 penetrated the packaging material 30 was measured. About five or more test pieces, the maximum value of stress was measured, and the average value was defined as the piercing strength of the packaging material 30. The environment during the measurement was a temperature of 23 ° C. and a relative humidity of 50%. As a result, the puncture strength was 13.0N.

[Evaluation of loop stiffness]
Further, the loop stiffness in the flow direction and the vertical direction of the packaging material 30 was measured. As a measuring instrument, No. manufactured by Toyo Seiki Co., Ltd. A 581 loop step tester (registered trademark) LOOP STIFFNESS TESTER DA type was used. The environment during the measurement was a temperature of 23 ° C. and a relative humidity of 50%. As a result, the loop stiffness in the flow direction of the packaging material 30 was 0.082 N, and the loop stiffness in the vertical direction was 0.077 N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 30 by the thickness of the packaging material 30 is 0.00102 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 30 is 0.00096 N. / Μm.

[Evaluation of impact resistance]
Further, the two packaging materials 30 were stacked and heated at 190 ° C. for 1 second, and the inner surfaces 30x of the packaging material 30 were heat-sealed. Next, the heat-sealed two packaging materials 30 were cut out with a width of 15 mm, and the test piece 100 was produced. 22 is a plan view showing the test piece 100, and FIG. 23 is a cross-sectional view of the test piece 100 of FIG. The test piece 100 has a width V1 of 15 mm and a length V2 of 50 mm, a seal portion 101 is formed over a length V3 of 10 mm from one end, and a length of 40 mm from the other end. The seal portion is not formed. Next, as shown in FIG. 24, the unsealed portion of one packaging material 30 and the unsealed portion of the other packaging material 30 are opposite to each other in a direction perpendicular to the surface direction of the seal portion 101. In other words, the end portion of the unsealed portion of one packaging material 30 and the end portion of the unsealed portion of the other packaging material 30 are respectively attached to the jig 102. , 103. At this time, the distance N between the jigs 102 and 103 in the direction orthogonal to the surface direction of the seal portion 101 was 40 mm. Subsequently, when one of the packaging materials 30 and the other packaging material 30 is separated by striking the one jig 102 with a hammer 104 from the surface of the one packaging material 30 on the first stretched plastic film 40 side. The impact strength of was measured. Evaluation was performed using a digital impact tester manufactured by Toyo Seiki Seisakusho Co., Ltd. As the hammer for applying an impact to the test piece 100, a 2J hammer was used. As a result, the impact strength was 374 kJ / m.

[Evaluation of tearability]
In addition, as shown in FIG. 25, the two packaging materials 30 joined through the sealant layer 70 were cut out so that the width V4 was 15 mm and the length V5 was 100 mm, and a test piece 95 was produced. The direction of the width V4 of the test piece 95 is parallel to the second direction D2 shown in FIG. The direction of the length V5 of the test piece 95 is parallel to the flow direction (MD) when a film such as a stretched plastic film or a sealant film is formed, and is parallel to the first direction D1 shown in FIG. It is. Subsequently, as shown in FIG. 25, a cut 28 was formed in the center of the test piece 95 in the direction of the width V4. Subsequently, the test piece 95 was manually torn in the direction of the length V5 starting from the notch 28. As a result, the test piece 95 could be torn in the direction of the length V5 without the sealant layer 70 of the packaging material 30 extending along the way.

[Evaluation of openability and heat resistance]
Then, the bag 10 was produced using the packaging material 30, and the opening property and heat resistance of the bag 10 were evaluated. Specifically, first, the bag 10 shown in FIG. The height S1 of the bag 10 was 145 mm and the width S2 was 150 mm. Further, the height S3 of the folded lower film 16, that is, the height from the lower end portion of the bag 10 to the folded portion 16f was 43 mm. In the following description, the bag 10 having a height S1 of 145 mm, a width S2 of 150 mm, and a height S3 of 43 mm is also referred to as an M size bag 10. Subsequently, 100 g of content containing a large amount of oil such as meat and miso was filled into the bag 10 through the opening 11 b of the upper portion 11. At this time, the openability of the opening 11b was evaluated. Specifically, as shown in FIG. 12, when a lateral force P is applied to the bag 10 using the chuck 111, the front film 14 and the back film 15 each have a curved shape that is convex on the outer surface side. It was confirmed whether it deform | transformed so that it may have. As a result, the front film 14 and the back film 15 were deformed so as to have a curved shape that is convex on the outer surface side.

After filling the bag 10 with the contents, the upper part 11 was heat-sealed to form an upper seal part 11a. Then, the bag 10 in which the contents were accommodated was heated for 2 minutes using the microwave oven of 500 W, and it was confirmed whether the packaging material 30 which comprises the bag 10 was damaged. The test was performed on 10 bags 10. As a result, it was confirmed that in 10 of 10 bags 10, there was no damage such as a hole in the packaging material 30 or formation of wrinkles in the packaging material 30.

(Example A2)
A packaging material 30 was produced in the same manner as in Example A1, except that an unstretched polypropylene film ZK207 manufactured by Toray Film Processing Co., Ltd. was used as the sealant layer 70. The thickness of the sealant layer 70 was 70 μm. The total thickness of the packaging material 30 was 90.5 μm.

ZK207 has a high tensile elastic modulus. Specifically, the tensile modulus of elasticity of ZK207 in the flow direction (MD) is 780 MPa when the thickness is 50 μm and 680 MPa when the thickness is 60 μm. Further, the tensile modulus of elasticity of ZK207 in the vertical direction (TD) is 630 MPa when the thickness is 50 μm and 560 MPa when the thickness is 60 μm. Therefore, the product of the tensile modulus (MPa) and the thickness (μm) of ZK207 in the flow direction is 39000 when the thickness is 50 μm and 40800 when the thickness is 60 μm. The product of the tensile modulus (MPa) and thickness (μm) of ZK207 in the vertical direction is 31500 when the thickness is 50 μm and 33600 when the thickness is 60 μm.

ZK207 also has a low tensile elongation. Specifically, the tensile elongation of ZK207 in the flow direction (MD) is 790% when the thickness is 50 μm and 730% when the thickness is 60 μm. The tensile elongation of ZK207 in the vertical direction (TD) is 1020% when the thickness is 50 μm, and 870% when the thickness is 60 μm. Therefore, the product of the tensile elongation (%) and thickness (μm) of ZK207 in the flow direction is 39500 when the thickness is 50 μm and 43800 when the thickness is 60 μm. The product of the tensile elongation (%) and the thickness (μm) of ZK207 in the vertical direction is 51000 when the thickness is 50 μm and 52200 when the thickness is 60 μm.

Subsequently, the puncture strength, impact strength, and loop stiffness of the packaging material 30 were measured in the same manner as in Example A1. As a result, the puncture strength was 13.2 N, and the impact strength was 287 kJ / m. The loop stiffness in the flow direction of the packaging material 30 was 0.091 N, and the loop stiffness in the vertical direction was 0.088 N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 30 by the thickness of the packaging material 30 is 0.00101 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 30 is 0.00097 N. / Μm.

Subsequently, the tearability of the packaging material 30 was evaluated in the same manner as in Example A1. As a result, the test piece 95 could be torn in the direction of the length V5 without the sealant layer 70 of the packaging material 30 extending along the way.

Subsequently, in the same manner as in Example A1, a bag 10 was produced using the packaging material 30, and the opening of the bag 10 when the bag 10 was filled with the contents was evaluated. The size of the bag 10 was set to M size as in the case of Example A1. As a result, the front film 14 and the back film 15 were deformed so as to have a curved shape that is convex on the outer surface side. Moreover, the heat resistance of the bag 10 containing the contents was evaluated in the same manner as in Example A1. As a result, although the wrinkle was formed in the packaging material 30, it confirmed that the packaging material 30 did not have a hole.

(Example A3)
A packaging material 30 was produced in the same manner as in Example 1 except that an unstretched polypropylene film ZK500R manufactured by Toray Film Processing Co., Ltd. was used as the sealant layer 70. The thickness of the sealant layer 70 was 50 μm. The total thickness of the packaging material 30 was 70.5 μm.

ZK500R has a high tensile elastic modulus. Specifically, the tensile modulus of elasticity of ZK500R in the flow direction (MD) is 980 MPa when the thickness is 50 μm. The tensile modulus of elasticity of ZK500R in the vertical direction (TD) is 780 MPa when the thickness is 50 μm. Therefore, the product of the tensile modulus (MPa) and the thickness (μm) of ZK500R in the flow direction is 49000 when the thickness is 50 μm. The product of the tensile modulus (MPa) and the thickness (μm) of ZK500R in the vertical direction is 39000 when the thickness is 50 μm.

Also, ZK500R has a low tensile elongation. Specifically, the tensile elongation of ZK500R in the flow direction (MD) is 770% when the thickness is 50 μm. Further, the tensile elongation of ZK500R in the vertical direction (TD) is 870% when the thickness is 50 μm. Therefore, the product of the tensile elongation (%) and thickness (μm) of ZK500R in the flow direction is 38500 when the thickness is 50 μm. The product of the tensile elongation (%) and thickness (μm) of ZK500R in the vertical direction is 43500 when the thickness is 50 μm.

Subsequently, the puncture strength, impact strength, and loop stiffness of the packaging material 30 were measured in the same manner as in Example A1. As a result, the puncture strength was 13.6 N, and the impact strength was 263 kJ / m. The loop stiffness in the flow direction of the packaging material 30 was 0.067 N, and the loop stiffness in the vertical direction was 0.057 N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 30 by the thickness of the packaging material 30 is 0.00095 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 30 is 0.00081 N. / Μm.

Subsequently, the tearability of the packaging material 30 was evaluated in the same manner as in Example A1. As a result, the test piece 95 could be torn in the direction of the length V5 without the sealant layer 70 of the packaging material 30 extending along the way. In addition, the amount of displacement of the two packaging materials 30 at the torn portions in the direction of the width V4 was 5 mm or less.

Subsequently, in the same manner as in Example A1, a bag 10 was produced using the packaging material 30, and the opening of the bag 10 when the bag 10 was filled with the contents was evaluated. The size of the bag 10 was set to M size as in the case of Example A1. As a result, the front film 14 and the back film 15 were deformed so as to have a curved shape that is convex on the outer surface side. Moreover, the heat resistance of the bag 10 containing the contents was evaluated in the same manner as in Example A1. As a result, although the wrinkle was formed in the packaging material 30, it confirmed that the packaging material 30 did not have a hole.

(Comparative Example A1)
A packaging material 30 was produced in the same manner as in Example A2, except that two stretched PET films having a thickness of 12 μm were joined as the base material 35 by an adhesive layer. The total thickness of the packaging material 30 was 102 μm.

Subsequently, the puncture strength and loop stiffness of the packaging material 30 were measured in the same manner as in Example A1. As a result, the piercing strength was 13.2N. The loop stiffness in the flow direction of the packaging material 30 was 0.102 N, and the loop stiffness in the vertical direction was 0.095 N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 30 by the thickness of the packaging material 30 is 0.00100 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 30 is 0.00093 N. / Μm.

Subsequently, the tearability of the packaging material 30 was evaluated in the same manner as in Example A1. As a result, the sealant layer 70 of the packaging material 30 was stretched midway, and the test piece 95 could not be torn in the direction of the length V5.

Subsequently, in the same manner as in Example A1, a bag 10 was produced using the packaging material 30, and the opening of the bag 10 when the bag 10 was filled with the contents was evaluated. The size of the bag 10 was set to M size as in the case of Example A1. As a result, the front film 14 and the back film 15 were deformed so as to have a curved shape that is convex on the outer surface side. Moreover, the heat resistance of the bag 10 containing the contents was evaluated in the same manner as in Example A1. As a result, although the wrinkle was formed in the packaging material 30, it confirmed that the packaging material 30 did not have a hole.

(Comparative Example A2)
A packaging material 30 was produced in the same manner as in Example A2, except that a stretched PET film having a thickness of 12 μm was used as the stretched plastic film 60. The total thickness of the packaging material 30 was 86.5 μm.

Subsequently, the puncture strength, impact strength, and loop stiffness of the packaging material 30 were measured in the same manner as in Example A1. As a result, the puncture strength was 11.1 N, and the impact strength was 301 kJ / m. The loop stiffness in the flow direction of the packaging material 30 was 0.071 N, and the loop stiffness in the vertical direction was 0.069 N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 30 by the thickness of the packaging material 30 is 0.00082 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 30 is 0.00080 N. / Μm.

Subsequently, the tearability of the packaging material 30 was evaluated in the same manner as in Example A1. As a result, the sealant layer 70 of the packaging material 30 was stretched midway, and the test piece 95 could not be torn in the direction of the length W5.

Subsequently, in the same manner as in Example 1, the bag 10 was produced using the packaging material 30, and the opening property when the bag 10 was filled with the contents was evaluated. The size of the bag 10 was set to M size as in the case of Example A1. As a result, the surface film 14 and the back film 15 are also formed with a plurality of curved portions that are convex on the inner surface side in addition to the plurality of curved portions that are convex on the outer surface side. Could not be secured. Moreover, the heat resistance of the bag 10 containing the contents was evaluated in the same manner as in Example A1. As a result, although the wrinkle was formed in the packaging material 30, it confirmed that the packaging material 30 did not have a hole.

(Example A4)
The packaging material 30 is the same as in Example A1, except that a sealant film made of a mixed resin containing low-density polyethylene and linear low-density polyethylene and having a melting point of 105 ° C. is used as the sealant layer 70. Was made. The thickness of the sealant layer 70 was 50 μm. The total thickness of the packaging material 30 was 70.5 μm.

Subsequently, the puncture strength and loop stiffness of the packaging material 30 were measured in the same manner as in Example A1. As a result, the piercing strength was 12.1N. The loop stiffness in the flow direction of the packaging material 30 was 0.050 N, and the loop stiffness in the vertical direction was 0.055 N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 30 by the thickness of the packaging material 30 is 0.00071 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 30 is 0.00078 N. / Μm.

(Example A5)
As the sealant layer 70, the packaging material 30 is provided in the same manner as in Example A1 except that a coextruded film having the first layer 71 and the second layer 72 shown in FIG. Produced. The first layer 71 was a layer made of polyethylene and having a thickness of 45 μm. The second layer 72 was a layer having a thickness of 5 μm containing a mixed resin of polyethylene and polypropylene. As the polyethylene, high density polyethylene having a density of 0.950 g / cm ³ was used. As the polypropylene, an ethylene-propylene random copolymer was used. The mass ratio of polypropylene and polyethylene in the second layer 72 was 7: 3. The thickness of the sealant layer 70 was 50 μm. The total thickness of the packaging material 30 was 70.5 μm.

Subsequently, the puncture strength and loop stiffness of the packaging material 30 were measured in the same manner as in Example A1. As a result, the piercing strength was 12.2N. The loop stiffness in the flow direction of the packaging material 30 was 0.053N, and the loop stiffness in the vertical direction was 0.052N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 30 by the thickness of the packaging material 30 is 0.00075 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 30 is 0.00074 N. / Μm.

FIG. 26 summarizes the layer configurations of Examples A1 to A5 and Comparative Examples A1 to A2, and the evaluation results regarding the piercing strength and loop stiffness. In addition, FIG. 27 summarizes the layer configurations of Examples A1 to A3 and Comparative Examples A1 to A2, and the evaluation results regarding impact strength, tearability, and heat resistance. In FIG. 26 and FIG. 27, in the “layer configuration” column, the components of the packaging material are described from the top in order from the outer layer. Further, in the “heat resistance” column, when holes and wrinkles were not formed in the packaging material 30, “great” was written, and wrinkles were formed in the packaging material 30, but no holes were formed. In this case, “good” was written, and when holes and wrinkles were formed in the packaging material 30, “bad” was written. In the “opening” column, when the front film 14 and the back film 15 are deformed so as to have a curved shape that is convex on the outer surface side, “good” is written. In addition to the plurality of curved portions that are convex on the outer surface side, a plurality of curved portions that are convex on the inner surface side are also indicated as “bad”.

As can be seen from the comparison between Examples A1 to A5 and Comparative Example A2, by using a high stiffness polyester film as the stretched plastic film 60, even when only one stretched plastic film is included in the packaging material 30, The puncture strength of the packaging material 30 could be increased to 12N or higher, for example, 13N or higher. Such a puncture strength is equivalent to the case where there are two stretched plastic films included in the packaging material 30, as can be seen from Comparative Example A1.

Further, as can be seen from the comparison between Examples A1 to A3 and Comparative Example A2, by using a high stiffness polyester film as the stretched plastic film 60, only one stretched plastic film is included in the packaging material 30. However, in at least one direction, the value obtained by dividing the loop stiffness of the packaging material 30 by the thickness of the packaging material 30 is 0.00085 N / μm or more, for example, 0.00090 N / μm or more, 0.00095 N / μm or more, or 0.0. It could be increased to 10000 N / μm or more. Thereby, the opening property of the bag 10 provided with the packaging material 30 was able to be improved.

Further, as can be seen from the comparison between Example A2 and Comparative Examples A1 and A2, the packaging material 30 includes a high stiffness polyester film, thereby suppressing the expansion of the sealant layer 70 when the packaging material 30 is torn. I was able to. Moreover, as can be seen from Example A3, the tearability of the packaging material 30 could be further improved by using ZK500R as the sealant layer 70. Regarding the tearability, in Examples A1 and A2, the test piece 95 could be smoothly torn across the entire area in the direction of the length V5, so the evaluation result was “good”. In Example A3, the test piece 95 can be smoothly torn across the entire area in the direction of the length V5, and the position of the two packaging materials 30 constituting the test piece 95 in the direction of the width V4 Since the deviation amount was 5 mm or less, the evaluation result was set to “great”. On the other hand, in Comparative Examples A1 and A2, the sealant layer 70 of the packaging material 30 stretched in the middle, and therefore, the test piece 95 could not be torn smoothly over the entire area in the direction of the length V5. The result was “bad”.

Further, as can be seen from Example A1, by using ZK500 as the sealant layer 70, it was possible to prevent the packaging material 30 of the bag 10 from being damaged during heating. The characteristic that the hot seal strength is low in ZK500 is considered to contribute to the suppression of damage.

Next, examples and comparative examples relating to the case where the packaging material 210 has the barrier laminate film 205 described in the second embodiment will be described.

[Example B1]
As the base material 201, a high stiffness PET film having a loop stiffness of 0.0017 N or more and made of petroleum-derived PET was prepared. Specifically, XP-55 manufactured by Toray Industries, Inc. was used as a high stiffness PET film. The thickness of the high stiffness PET film was 16 μm. The measured value of the loop stiffness of the high stiffness PET film was 0.0021 N in both the flow direction and the vertical direction. Moreover, the tensile elasticity modulus of the high stiffness PET film in the flow direction was 4.8 GPa, and the tensile elasticity modulus of the high stiffness polyester film in the vertical direction was 4.7 GPa.
The tensile strength of the high stiffness PET film in the flow direction was 292 MPa, and the tensile strength of the high stiffness polyester film in the vertical direction was 257 MPa. Further, the tensile elongation of the high stiffness PET film in the flow direction was 107%, and the tensile elongation of the high stiffness polyester film in the vertical direction was 102%. In this case, the value obtained by dividing the tensile strength of the high stiffness PET film in the flow direction by the tensile elongation is 2.73 [MPa /%], and the tensile strength of the high stiffness PET film in the vertical direction is divided by the tensile elongation. The value is 2.52 [MPa /%].
In addition, the thermal shrinkage rate of the high stiffness PET film in the flow direction and the vertical direction was both 0.4%.

Subsequently, the puncture strength of the high stiffness PET film was measured according to JIS Z1707 7.4. As a measuring instrument, Tensilon universal material testing machine RTC-1310 manufactured by A & D was used. Specifically, a semi-circular needle having a diameter of 1.0 mm and a tip shape radius of 0.5 mm is applied to the test piece of the high stiffness PET film in a fixed state from the outer surface 30y side at 50 mm / min (1 The maximum value of the stress until the needle penetrated the high stiffness PET film was measured at a speed of 50 mm per minute). About five or more test pieces, the maximum value of stress was measured, and the average value was defined as the piercing strength of the high stiffness PET film. The environment during the measurement was a temperature of 23 ° C. and a relative humidity of 50%. As a result, the piercing strength was 10.2N.

[Example B2]
As the base material 201, a PBT film including a plurality of layers described in the first configuration and produced by a casting method was prepared. The PBT content in each layer was 80%, the number of layers was 1024, and the thickness of the PBT film was 15 μm. Moreover, the tensile strength of the PBT film in the flow direction was 191 MPa, and the tensile strength of the PBT film in the vertical direction was 289 MPa. Further, the tensile elongation of the PBT film in the flow direction was 195%, and the tensile elongation of the PBT film in the vertical direction was 100%. In this case, the value obtained by dividing the tensile strength of the PBT film in the flow direction by the tensile elongation is 0.98 [MPa /%], and the value obtained by dividing the tensile strength of the PBT film in the vertical direction by the tensile elongation is 2. 89 [MPa /%].
Further, the thermal shrinkage rate of the PBT film in the flow direction and the vertical direction was both 0.4%.

[Example C1]
First, the vapor deposition layer 202 was formed on the base material 201, the gas barrier coating film 203 was formed on the vapor deposition layer 202, and the barrier property laminated film 205 was produced. Then, the packaging material 210 provided with the barriering laminated film 205 was produced.

First, production of the barrier laminate film 205 will be described. First, the roll which wound up the 16-micrometer-thick high stiffness PET film used by the above-mentioned Example B1 as the base material 201 was prepared. Subsequently, after the substrate 201 was subjected to oxygen plasma treatment using the above-described film forming apparatus 260 shown in FIG. 20, a vapor deposition layer 202 having a thickness of 12 nm containing aluminum oxide was formed on the oxygen plasma treatment surface. . Hereinafter, the oxygen plasma process and the film forming process will be described in detail.

In the oxygen plasma processing, plasma is introduced from the plasma supply nozzle 272 under the following conditions in the plasma pretreatment chamber 262B on the surface of the base material 201 where the vapor deposition layer 202 is provided, and is transported at a transport speed of 400 m / min. The material 201 was subjected to plasma pretreatment. Thereby, the oxygen plasma processing surface was formed in the surface in which the vapor deposition layer 202 was provided among the base materials 201. FIG.
[Oxygen plasma pretreatment conditions]
・ Plasma intensity: 200 W · sec / m ²
・ Plasma forming gas ratio: Oxygen / Argon = 2/1
・ Applied voltage between pretreatment drum and plasma supply nozzle: 340V
-Vacuum degree of pretreatment section: 3.8 Pa

In the film formation process, in the film formation chamber 262C into which the base material 201 continuously transferred from the plasma pretreatment chamber 262B is carried, aluminum is used as a target on the oxygen plasma processing surface of the base material 201. A vapor deposition layer 202 containing aluminum oxide having a thickness of 12 nm was formed on the substrate 201 by a vacuum vapor deposition method. As a heating means of the vacuum deposition method, a reactive resistance heating method was adopted. The film forming conditions are as follows.
[Aluminum oxide deposition conditions]
・ Degree of vacuum: 8.1 × 10 ⁻² Pa
・ Conveying speed: 400m / min
・ Oxygen gas supply amount: 20000 sccm

Subsequently, a gas barrier coating film 203 was formed on the vapor deposition layer 202. Specifically, first, 385 g of water, 67 g of isopropyl alcohol, and 9.1 g of 0.5N hydrochloric acid were mixed and adjusted to pH 2.2, and then 175 g of tetraethoxysilane as a metal alkoxide and glycid as a silane coupling agent. A solution A was prepared by mixing 9.2 g of xylpropyltrimethoxysilane while cooling to 10 ° C.
As a water-soluble polymer, a solution B was prepared by mixing 14.7 g of polyvinyl alcohol having a degree of polymerization of 2400 with a ken number of 99% or more, 324 g of water, and 17 g of isopropyl alcohol.
Then, A liquid and B liquid were mixed so that it might become a weight ratio 6.5: 3.5. The solution thus obtained was used as a coating agent for a gas barrier coating film.

The gas barrier coating film coating agent prepared above was coated on the vapor deposition layer 202 by a spin coating method. Thereafter, heat treatment was performed in an oven at 180 ° C. for 60 seconds to form a gas barrier coating film 203 having a thickness of about 400 nm on the vapor deposition layer 202. In this way, a barrier laminate film 205 having a base material 201, a vapor deposition layer 202, and a gas barrier coating film 203 was obtained.

(Transformation rate)
In a vacuumed environment, time-of-flight secondary ion mass spectrometry (TOF) is performed while repeatedly performing soft etching on the surface of the gas barrier coating film 203 of the barrier laminate film 205 with a Cs (cesium) ion gun at a constant rate. -SIMS), ions derived from the gas barrier coating film 203, ions derived from the vapor deposition layer 202, and ions derived from the substrate 201 were measured. For example, _{C 6} (mass number 72.00) derived from the resin film of the substrate 201, _Al 2 _O 4 H (mass number 118.93) from aluminum oxide deposited film of the deposited layer 202 was subjected to mass analysis of ions.

A time-of-flight secondary ion mass spectrometer used for TOF-SIMS is manufactured by ION TOF, TOF. The measurement was performed under the following measurement conditions using SIMS5. As a result, a graph as shown in FIG. 19 was obtained.
(TOFSIMS measurement conditions)
Primary ion type: Bi ₃ ++ (0.2 pA, 100 μs)
Measurement area: 150 × 150 μm ²
Etching gun type: Cs (1 keV, 60 nA)
Etching area: 600 × 600 μm ²
Etching Et rate: 3 sec / Cycle
Vacuuming time: 15 hours or longer at 1 × 10 ⁻⁶ mbar or less Measurement using a time-of-flight secondary ion mass spectrometer was performed within 30 hours after the start of vacuuming.

In the graph, the positions at which the strength of SiO ₂ (mass number 59.96), which is a constituent element of the gas barrier coating film 203, is half the strength of the gas barrier coating film 203 are determined between the gas barrier coating film 203 and the vapor deposition layer 202. Identified as an interface. In addition, the position where the strength of C ₆ (mass number 72.00), which is a constituent material of the base material 201, becomes half the strength of the base material 201 was specified as the interface between the base material 201 and the vapor deposition layer 202. Moreover, the distance in the thickness direction between the two interfaces was adopted as the thickness of the vapor deposition layer 202.

Next, a peak representing the measured element-bound Al ₂ O ₄ H (mass number 118.93) was determined, and the transition from the peak to the interface was taken as the transition region. However, when the component of the gas barrier coating film 203 is made of a material having the same mass number as Al ₂ O ₄ H (mass number 118.93), it is necessary to separate the waveform of 118.93.

When reactants AlSiO ₄ and hydroxide Al ₂ O ₄ H are generated at the interface between the gas barrier coating film 203 and the vapor deposition layer 202, Al and the Al present at the interface between the substrate 201 and the vapor deposition layer 202 are present. ₂ O ₄ H can be separated. As described above, the waveform separation can be appropriately handled according to the material of the gas barrier coating film 203.

In waveform separation, for example, a profile with a mass number of 118.93 obtained by TOF-SIMS is subjected to nonlinear curve fitting using a Gaussian function, and overlapping peaks are separated using a least square method Levenberg Marquardt algorithm. You may go.

Two samples were prepared from the barrier laminate film 205 of Example C1, and for each of the two samples, the conversion rate of the vapor deposition layer 202 was expressed as (transition region thickness W ₁ / vapor deposition layer 202 thickness) × 100 (% ). As a result, the modification rate in the first sample was 36.2%, and the modification rate in the second sample was 28.8%.

Next, production of the packaging material 210 including the barrier laminate film 205 will be described. First, a printing layer 218 having a thickness of 1 μm was formed on the gas barrier coating film 203 of the barrier laminate film 205. Further, the film including the barrier laminate film 205 and the film constituting the sealant layer 212 were bonded together by a dry laminating method through the first adhesive layer 213 having a thickness of 3.5 μm. As the film of the sealant layer 212, an unstretched polypropylene film (thickness 60 μm) was used. As the unstretched polypropylene film, unstretched polypropylene film ZK207 manufactured by Toray Film Processing Co., Ltd. was used. In this way, a packaging material 210 having the layer configuration shown in FIG. 16 was produced. The total thickness of the packaging material 210 was 80.5 μm.

The layer structure of the packaging material 210 of the present embodiment is expressed as follows.
High PET16 / Transparent Deposition / Barrier / Mark / Adhesive / CPP60
“High PET” means high stiffness PET film. “Transparent deposition” means a transparent deposition layer containing aluminum oxide. “Barrier” means a gas barrier coating film. “Mark” means a printed layer. “Adhesive” means an adhesive layer. “CPP” means an unstretched polypropylene film. The number means the thickness of the layer (unit: μm).

Subsequently, the puncture strength and loop stiffness of the packaging material 210 were measured in the same manner as in Example A1. As a result, the piercing strength was 13.2N. The loop stiffness in the flow direction of the packaging material 210 was 0.084 N, and the loop stiffness in the vertical direction was 0.079 N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 210 by the thickness of the packaging material 210 is 0.00104 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 210 is 0.00098N. / Μm.

Further, as described below, after the retort treatment was applied to the packaging material 210 of Example C1, the oxygen permeability and the water vapor permeability were measured.

(Oxygen permeability)
A four-sided seal pouch was prepared using the packaging material 210. Subsequently, 100 mL of water was injected into the inside of the four-way seal pouch from the opening at the top of the four-way seal pouch, and then a seal portion was formed on the upper portion to seal the four-way seal pouch. Subsequently, the four-side seal pouch was subjected to a retort treatment at 121 ° C. for 40 minutes and 2 atmospheres.
Then, the packaging material 210 which comprises the single side | surface of the four-sided seal pouch after the retort process was cut out, and the sample for evaluating the oxygen permeability after a retort process was produced.

Subsequently, the sample after the retort treatment is set so that the base material 201 is on the oxygen supply side, and the oxygen permeability is measured in accordance with JIS K 7126 B method under measurement conditions in an atmosphere of 23 ° C. and 100% RH. Was measured. As a measuring device, an oxygen permeability measuring device (manufactured by Modern Control (MOCON) [model name: OX-TRAN 2/21]) was used. Result, the oxygen permeability of the sample after retort treatment was less than ^{1.5cc / m 2 / 24hr / atm} .

(Water vapor permeability)
The water vapor permeability was measured using the same sample as that used for measuring the oxygen permeability. Specifically, each sample was set so that the base material 201 was on the sensor side, and the water vapor transmission rate was compliant with the JIS K 7126 B method under measurement conditions in an atmosphere of 37.8 ° C. and 100% RH. Was measured. As a measuring device, a water vapor permeability measuring device (a measuring machine manufactured by MOCON [model name, PERMATRAN 3/33]) was used. Result, the water vapor permeability of the sample after retort treatment was less than 2.0g / m ² / 24hr.

The packaging material 210 of the present embodiment can be used, for example, to configure a pouch that is subjected to retort processing.

[Example C2]
In the same manner as in Example C1, a barrier laminate film 205 was produced. Subsequently, as in the case of Example C1, except that a sealant film (thickness 50 μm) made of a mixed resin of low density polyethylene and linear low density polyethylene was used as the film of the sealant layer 212, A packaging material 210 having the layer configuration shown in FIG. The total thickness of the packaging material 210 was 70.5 μm.

The layer structure of the packaging material 210 of the present embodiment is expressed as follows.
High PET16 / transparent deposition / barrier / mark / adhesive / blend PE50
“Blend PE” means a sealant film made of a mixed resin of low density polyethylene and linear low density polyethylene.

Subsequently, the puncture strength and loop stiffness of the packaging material 210 were measured in the same manner as in Example A1. As a result, the piercing strength was 12.5N. The loop stiffness in the flow direction of the packaging material 210 was 0.051N, and the loop stiffness in the vertical direction was 0.053N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 210 by the thickness of the packaging material 210 is 0.00072 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 210 is 0.00075 N. / Μm.

Also, as described below, after the boil treatment was applied to the packaging material 210 of Example B2, the oxygen permeability and the water vapor permeability were measured.

(Oxygen permeability)
A four-sided seal pouch was prepared using the packaging material 210. Subsequently, 100 mL of water was injected into the inside of the four-way seal pouch from the opening at the top of the four-way seal pouch, and then a seal portion was formed on the upper portion to seal the four-way seal pouch. Subsequently, the four-side seal pouch was boiled at 95 ° C. for 60 minutes.
Subsequently, the packaging material 210 constituting one side of the four-sided seal pouch after the boil treatment was cut out, and a sample for evaluating the oxygen permeability after the boil treatment was produced. Subsequently, the oxygen permeability of the sample after the boil treatment was measured in the same manner as in Example C1. Result, the oxygen permeability was less than ^{1.5cc / m 2 / 24hr / atm} .

(Water vapor permeability)
Using the same sample as in the measurement of oxygen permeability, the water vapor permeability of the sample after the boil treatment was measured in the same manner as in Example C1. Result, water vapor permeability was less than 2.0g / m ² / 24hr.

The packaging material 210 of the present embodiment can be used to configure a pouch that is subjected to boil processing, for example.

[Example C3]
In the same manner as in Example C1, a barrier laminate film 205 was produced. Subsequently, as a film of the sealant layer 212, the sealant film including the first layer 2121 and the second layer 2122 shown in FIG. 17 and formed by co-extrusion and having an easy peel property (thickness 50 μm) is used. In the same manner as in Example C1, a packaging material 210 having the layer configuration shown in FIG. 17 was produced. The first layer 2121 is a layer having a thickness of 5 μm made of a mixed resin of high-density polyethylene and polypropylene. The second layer 2122 is a layer made of high-density polyethylene and having a thickness of 45 μm. The total thickness of the packaging material 210 was 70.5 μm.

The layer structure of the packaging material 210 of the present embodiment is expressed as follows.
High PET16 / Transparent Deposition / Barrier / Mark / Adhesive / Easy Peel 50
“Easy peel” means a sealant film including a layer made of a mixed resin of polyethylene and polypropylene and having easy peel properties.

Subsequently, the puncture strength and loop stiffness of the packaging material 210 were measured in the same manner as in Example A1. As a result, the piercing strength was 12.4N. The loop stiffness in the flow direction of the packaging material 210 was 0.054N, and the loop stiffness in the vertical direction was 0.054N. In this case, the value obtained by dividing the loop stiffness in the flow direction of the packaging material 210 by the thickness of the packaging material 210 is 0.00077 N / μm, and the value obtained by dividing the loop stiffness in the vertical direction by the thickness of the packaging material 210 is 0.00077 N. / Μm.

Subsequently, as in Example C1, after the retort treatment was performed on the four-sided seal pouch produced using the packaging material 210, the oxygen permeability was measured using the sample cut out from the four-way seal pouch, and the water vapor transmission rate. The degree of measurement was taken. Result, the oxygen permeability of the sample after retort treatment was less than ^{1.5cc / m 2 / 24hr / atm} . Further, water vapor permeability of the sample after retort treatment was less than 2.0g / m ² / 24hr.

The packaging material 210 of the present embodiment can be used, for example, to constitute a lid material for a container with a lid that is subjected to a retort process. The container body of the lidded container can be made of, for example, polypropylene.

The layer structure of the packaging material 210 of Examples C1 to C3, and the evaluation results relating to the piercing strength and loop stiffness are collectively shown in FIG. Further, FIG. 29 shows the layer structure of the packaging material 210 of Examples C1 to C3, the evaluation result of the oxygen permeability, and the evaluation result of the water vapor permeability. In the column of "oxygen permeability" in FIG. 29, "OK" is oxygen permeability of the sample after retort treatment means that was less than ^{1.5cc / m 2 / 24hr / atm} . Further, in the column of "water vapor transmission rate" in FIG. 29, "OK" means that the water vapor permeability of the sample after retort treatment was less than 2.0g / m ² / 24hr.

As can be seen from Examples C1 to C3, when a high stiffness polyester film is used as the stretched plastic film 60, the packaging material 30 includes only one stretched plastic film, as in Examples A1 to A5. Even so, the puncture strength of the packaging material 30 could be increased to 12N or higher, for example, 13N or higher. In Example C1 using an unstretched polypropylene film ZK207 manufactured by Toray Film Processing Co., Ltd. as the sealant layer 70, a value obtained by dividing the loop stiffness of the packaging material 30 by the thickness of the packaging material 30 in at least one direction, It could be increased to 0.00085 N / μm or more, specifically 0.00095 N / μm or more, or 0.00100 N / μm or more.

10 bags (pouches)
DESCRIPTION OF SYMBOLS 11 Upper part 12 Lower part 12a Lower seal part 13 Side part 13a Side part seal part 14 Surface film 15 Back surface film 16 Lower film 17 Storage part 18 Contents 20 Vapor release mechanism 20a Vapor release seal part 25 Easy-opening means 26 Notch 30 Packaging material 35 Base material 60 Stretched plastic film 65 Adhesive layer 70 Sealant layer 80 Test piece 80A Flow direction test piece 80B Vertical direction test piece 80x Inner surface 80y Outer surface 81 Loop portion 82 Intermediate portion 83 Fixed portion 85 Loop stiffness measuring device 86 Chuck portion 861 First chuck 862 Second chuck 87 Support member 88 Load cell 201 Base material 202 Deposition layer 203 Gas barrier coating film 205 Barrier laminated film 210 Packaging material 212 Sealant layer 2121 First layer 2122 Second layer 213 First adhesive layer 218 Printing layer

Claims (13)

Packaging material,
A substrate and a sealant layer;
The base material has only one biaxially stretched plastic film containing polyester as a main component,
A packaging material in which a value obtained by dividing the loop stiffness in one direction of the packaging material by the thickness of the packaging material is 0.00085 [N / μm] or more. Packaging material,
A substrate and a sealant layer;
The base material has only one biaxially stretched plastic film containing polyester as a main component,
The biaxially stretched plastic film is a packaging material having a loop stiffness of 0.0017 N or more in one direction. Packaging material,
A substrate and a sealant layer;
The substrate has only one biaxially stretched plastic film containing polyethylene terephthalate as a main component,
A packaging material in which the puncture strength of the packaging material is 12 N or more. Packaging material,
A substrate and a sealant layer;
The base material has only one biaxially stretched plastic film containing polyester as a main component,
A packaging material having a value obtained by dividing the tensile strength of the biaxially stretched plastic film by the tensile elongation in at least one direction is 2.0 [MPa /%] or more. The packaging material according to claim 1, 2, or 4, wherein the biaxially stretched plastic film contains polyethylene terephthalate as a main component. The packaging material according to claim 1, 2, 4, or 5, wherein the puncture strength of the packaging material is 12N or more. The packaging material according to any one of claims 1 to 6, further comprising a printing layer. The packaging material according to any one of claims 1 to 7, further comprising: a vapor deposition layer located on a surface of the biaxially stretched plastic film; and a gas barrier coating film located on the vapor deposition layer. The packaging material according to any one of claims 1 to 8, wherein the sealant layer contains polypropylene as a main component. The packaging material according to any one of claims 1 to 8, wherein the sealant layer includes polyethylene having a melting point of 100 ° C or higher. The said sealant layer has a 1st layer which has polyethylene or a polypropylene as a main component, and a 2nd layer located in the inner surface side rather than a 1st layer and containing the mixed resin of polyethylene and a polypropylene. The packaging material according to any one of the above. A retort pouch comprising the packaging material according to any one of claims 1 to 11. A microwave oven pouch having a storage portion,
The packaging material according to any one of claims 1 to 11,
A microwave oven pouch comprising: a seal portion that joins the inner surfaces of the packaging material, the seal portion including a steam vent seal portion that peels off due to an increase in pressure in the housing portion.

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