WO2025191480A1 - Chemical solution bag - Google Patents

Abstract

The present invention provides a chemical solution bag that has exceptional resistance to radiation while enhancing adhesion between a bag body and a port member. More specifically, the present invention is a chemical solution bag having a bag body for accommodating contents and a cylindrical port member attached to the bag body, wherein: the bag body is formed by molding a sheet member into the form of a bag; the sheet member includes an innermost layer and a base resin layer; the innermost layer contains, as a main component, an amorphous polymer having a cyclic hydrocarbon skeleton; the port member includes a port material; and the sealing strength of the port material with respect to a base material containing a cyclic olefin is 30 N/15 mm or greater.

Description

Medicine bag

The present invention relates to a drug solution bag.

Medicinal solution bags are used as packaging for storing medicinal solutions (chemicals) used for medical treatment, disinfection, herbicides, etc. A medicinal solution bag generally consists of a container formed into a bag shape using a resin film to hold the medicinal solution, and a port member for filling or discharging the medicinal solution. The container is formed, for example, by stacking laminates made of multiple types of resin films with a port member sandwiched between them, and joining the outer periphery by heat sealing or other methods. Before or after storing the medicinal solution in the container, the medicinal solution bag is sterilized and sealed using radiation such as gamma rays or electron beams.

One such medical infusion bag has been disclosed, which includes a bag body made of polyethylene film shaped into a bag shape to contain the infusion liquid, and a tube port welded to the bottom of the bag body for discharging the infusion liquid from the bag body. In this medical infusion bag, the tube port has a multilayer structure with an outer layer made of high-density polyethylene, an inner layer made of a resin material containing random polypropylene and/or block polypropylene, and an adhesive layer joining the outer and inner layers (see, for example, Patent Document 1).

Japanese Patent No. 5632226

However, the medical infusion bag described in Patent Document 1 had the problem that the polyethylene film that makes up the bag body was prone to adsorbing the contained medicinal ingredients and causing the medicinal ingredients to leach out of the bag body.

Another possible method is to use a cyclic polyolefin resin as the material for forming the bag body, as this resin is less likely to adsorb medicinal ingredients and cause less elution of medicinal ingredients from the bag body than polyethylene film. However, because the outer layer of the tube port of the medical infusion bag described in Patent Document 1 is made of high-density polyethylene, there is insufficient adhesion between the bag body and the tube port, and there is a possibility that medicinal ingredients may elute from the joint between the bag body and the tube port.

Furthermore, because the inner layer of the tube port is made of polypropylene, it has low resistance to radiation sterilization and is easily deteriorated by radiation sterilization. When the inner layer of the tube port deteriorates due to radiation, the adhesive strength between the inner layer of the tube port and the adhesive layer decreases, reducing the durability of the tube port and posing the problem of the possibility of drug ingredients inside the bag body leaching out.

The present invention was made in consideration of the above circumstances, and aims to provide a chemical solution bag that has excellent radiation resistance while improving adhesion between the bag body and the port member (tube port).

In order to solve the above problems, the present invention has the following configuration.
[1] A drug solution bag having a bag body that accommodates contents and a cylindrical port member attached to the bag body,
The bag body is formed by molding a sheet member into a bag shape,
the sheet member includes an innermost layer and a base resin layer, the innermost layer containing an amorphous polymer having a cyclic hydrocarbon skeleton as a main component,
the port member includes a port material;
A drug solution bag, wherein the port material has a seal strength of 30 N/15 mm or more with respect to a substrate containing a cyclic olefin.
[2] The drug solution bag according to [1], wherein the port material has a tensile modulus of elasticity of 20 to 70 MPa.
[3] The drug solution bag according to [1] or [2], wherein the port material has an MFR of 3.8 to 20 g/10 min at 190°C.
[4] The drug solution bag according to any one of [1] to [3], wherein the port material contains one or more linear low-density polyethylenes.
[5] The drug solution bag according to any one of [1] to [4], wherein the port material contains linear low-density polyethylene and a resin having a tensile modulus of elasticity of 25 MPa or less.
[6] The drug solution bag according to [5], wherein the mass ratio of the content of the linear low-density polyethylene to the content of the resin having a tensile modulus of elasticity of 25 MPa or less is 60:40 to 75:25.
[7] The port material includes two different types of linear low-density polyethylene,
one of the two different linear low-density polyethylenes has a higher MFR at 190°C than the other linear low-density polyethylene;
The drug solution bag according to any one of [1] to [6], wherein the flexural modulus of the other linear low-density polyethylene is lower than the flexural modulus of the one linear low-density polyethylene.
[8] The MFR of the one linear low-density polyethylene at 190°C is 8 g/10 min or more,
The drug solution bag according to [7], wherein the other linear low-density polyethylene has a flexural modulus of 100 MPa or less.
[9] The drug solution bag according to any one of [1] to [8], wherein the contents are medicines.

The drug solution bag of the present invention provides excellent radiation resistance while improving adhesion between the bag body and the port member (tube port).

1 is a plan view of a medical solution bag according to an embodiment of the present invention; FIG. 2 is a cross-sectional view taken along the line II in FIG. 1 .

Embodiments of the present invention will be described in detail below with reference to the drawings. To facilitate understanding of the description, identical components are designated by the same reference numerals in each drawing, and duplicate explanations may be omitted. The scale of each member in the drawings may differ from the actual scale. In this specification, unless otherwise specified, the symbol "~" indicating a numerical range means that the numerical values before and after it are included as the lower and upper limits. Furthermore, when a unit is specified for only the upper limit value in a numerical range expressed with "~", it means that the lower limit value is also in the same unit.

<Medicine bag>
A chemical solution bag according to one embodiment of the present invention will be described. Fig. 1 is a plan view of the chemical solution bag according to this embodiment, and Fig. 2 is a cross-sectional view taken along the line I-I in Fig. 1. As shown in Fig. 1, the chemical solution bag 1 according to this embodiment includes a bag body 10 and a tubular port member 20 attached to the bag body 10, one end of which communicates with the interior of the bag body 10 and the other end of which is exposed to the outside of the bag body 10. The chemical solution bag 1 accommodates contents within the bag body 10. Before or after the contents are accommodated in the bag body 10, the chemical solution bag 1 is sterilized with radiation such as gamma rays or electron beams.

In this embodiment, the contents may include pharmaceuticals (drugs), cells, tissues, organs, biological materials, blood, body fluids, enzymes, antibodies, beauty products, nutrients, health supplements, cosmetics, and food. Of these, pharmaceuticals are preferred. Preferred examples of pharmaceuticals include chemically synthesized low-molecular-weight compounds (low-molecular-weight pharmaceuticals) and biopharmaceuticals (biological preparations) manufactured using polymers such as proteins. Preferred examples of biopharmaceuticals include protein preparations.

The form of the contents is not particularly limited and may be, for example, a solid, liquid, gas, powder, granules, a mixture, a composition, or a dispersion. Furthermore, if the contents are liquid, the liquid may be an aqueous solution containing a drug.

[Bag body]
As shown in Fig. 2, the bag body 10 is a packaging bag (pouch) formed into a bag shape by overlapping a pair of sheet members 100. The bag body 10 is manufactured by overlapping the pair of sheet members 100 so that they face each other, welding their outer peripheral edges together, and forming them into a bag shape.

The bag body 10 has a joint (seal) 11 formed by overlapping a pair of sheet members 100 facing each other and welding their outer peripheral edges together, a storage chamber 12 defined by the pair of sheet members 100 and the joint 11, and openings 13A and 13B where the outer peripheral edges of the pair of sheet members 100 are not welded together but are welded to the port member 20.

The joint 11 is provided in a closed ring shape around the periphery of the bag body 10. The joint 11 has a first joint 11-1 where the sheet members 100 are joined together, and a second joint 11-2 where the sheet members 100 are joined to the port member 20. As shown in FIG. 1 , the first joint 11-1 and the second joint 11-2 are formed continuously in a plan view of the bag body 10.

The storage chamber 12 is a space into which the contents are filled. Note that the specific state and shape of the contents are not shown in the drawings.

Openings 13A and 13B are gaps between opposing sheet members 100 that are not fused together, and are formed by welding or other means to the port member 20. Before the port member 20 is welded or other means, openings 13A and 13B may be used as filling ports for filling (injecting) the contents to be stored in the storage chamber 12.

Note that while the bag body 10 shown in Figure 1 is a four-sided bag, the shape of the bag body 10 is not particularly limited and may be, for example, a three-sided bag, a seamed bag, a gusseted bag, a self-standing bag, an inner bag for a bag-in-box, or an inner bag for a drum can.

(Sheet member)
Here, the pair of sheet members 100 constituting the bag body 10 will be described. As shown in Fig. 2, the sheet member 100 includes an innermost layer (sealing layer) 101, an adhesive resin layer (AD) 102, and a base resin layer 103, which are laminated in this order. The pair of sheet members 100 are overlapped with each other so that the innermost layers 101 of the sheet members 100 face each other, with the innermost layers 101 facing each other. Note that the sheet member 100 may be configured by laminating two or more layers, including the innermost layer 101 and the base resin layer 103.

The thickness of the sheet member 100 is not particularly limited, but is preferably 70 to 400 μm, and from the standpoint of the strength and flexibility required for the bag body 10, 150 to 300 μm is more preferable.

In this specification, the thickness of the sheet member 100 refers to the length in the direction perpendicular to the main surface of the sheet member 100. The thickness of the sheet member 100 may be, for example, the thickness measured at an arbitrary location on the cross section of the sheet member 100, or it may be measured at several arbitrary locations and the average value of these measurements may be used. Below, the definition of thickness is similar for other members.

The seal width around the periphery of the sheet member 100 is not particularly limited, but may be, for example, 2 to 20 mm.

((innermost layer))
The innermost layer 101 is used when the sheet members 100 are bonded together by heat sealing or the like to form a bag shape. The innermost layer 101 faces the storage chamber 12 and comes into contact with the contents.

The innermost layer 101 contains one or more types of olefin monomers, at least one of which is a monomer having a cyclic hydrocarbon skeleton, and contains an amorphous polymer composed of the monomer having the cyclic hydrocarbon skeleton as its main component. This makes the innermost layer 101 resistant to radiation and reduces deterioration when the chemical solution bag 1 is sterilized with radiation.

Note that "main component" means that the proportion of amorphous polymer in all components constituting the innermost layer 101 is 50% by mass or more. Note that the same meaning applies to each layer constituting the sheet member 100 and the port member 20.

The amorphous polymer, which is the main component of the innermost layer 101, is composed of at least one or more types of olefin monomers, at least one of which is a monomer having a cyclic hydrocarbon skeleton. Examples of amorphous polymers include polymers obtained by copolymerizing cyclic olefin monomers, and examples of cyclic olefin monomers include norbornene compounds. When the amorphous polymer is composed of only one type of cyclic olefin monomer (such as a norbornene compound), it may be a ring-opening metathesis polymer of a norbornene compound or the like, but it is preferable that it does not contain a homoaddition polymer of a norbornene compound or the like.

The amorphous polymer that is the main component of the innermost layer 101 includes a copolymer of two or more types of cyclic olefin monomers such as norbornene compounds, an addition polymer obtained by copolymerizing a cyclic olefin monomer with an olefin monomer (acyclic olefin monomer) other than a cyclic olefin monomer such as an α-olefin, or a polymer obtained by ring-opening metathesis polymerization of a cyclic olefin monomer such as a norbornene compound, followed by hydrogenation of the remaining double bonds. However, it is preferable that the polymer does not include a homoaddition polymer of only one type of cyclic olefin monomer. Hereinafter, polymers obtained by copolymerizing these cyclic olefin monomers are also referred to as "cyclic olefin polymers."

Examples of such cyclic olefin polymers include:

Known methods for producing cyclic olefin polymers include hydrogenating ring-opening metathesis polymers of norbornene compounds and copolymerizing norbornene compounds with α-olefins.

An example of the basic structure of a cyclic olefin polymer is formula (I) below. That is, the polymer of formula (I) below is a polymer in which cyclic unit skeletons and ethylene unit skeletons are alternately arranged. The cyclic skeleton of formula (1) below is a 1,3-cyclopentylene skeleton. However, the ring-opening metathesis polymer of a norbornene compound itself does not need to be a copolymer.

In formula (I), n is an integer of 1 or more, _R1 and _R2 are hydrogen atoms or alkyl groups, and may be the same or different. _R1 and _R2 may be bonded to form a ring.

The structure shown in the above formula (I) may be a homopolymer of one type of cyclic olefin monomer. That is, in the structure shown in the above formula (I), the substituents _R1 and _R2 possessed by the n 1,3-cyclopentylene skeletons may be the same, and the ring-opening metathesis polymer of the norbornene compound may be a homopolymer. Note that the structure shown in the above formula (I) is not limited to a homopolymer.

The structure shown in formula (I) above also encompasses copolymers made of multiple cyclic olefin monomers (wherein there are two or more combinations of _R1 and _R2 bonded to n cyclic unit skeletons). That is, the structure shown in formula (I) above may be a polymer obtained by hydrogenating a ring-opening metathesis polymer of two or more norbornene compounds. Examples of such polymers include those shown in formula (II) below.

In formula (II), m and n are integers of 1 or more, and _R1 and _R2 represent a hydrogen atom or an alkyl group. m and n may be the same as or different from each other. _R1 and _R2 may be the same as or different from each other. _R1 and _R2 may be bonded to each other to form a ring.

Specific examples of polymers obtained by hydrogenating ring-opening metathesis polymers of norbornene compounds include the ZEONEX (registered trademark) series and ZEONOR (registered trademark) series manufactured by Zeon Corporation.

Furthermore, an example of an addition polymer obtained by copolymerizing a cyclic olefin monomer and a non-cyclic olefin monomer is represented by the following formula (III). The addition polymer represented by the following formula (III) is a polymer in which cyclic skeletons and ethylene skeletons are randomly arranged. The cyclic skeleton in the following formula (III) is a 2,3-norbornanylene skeleton.

In formula (III), m and n are integers of 1 or more, and R ₁ , R ₂ , and R ₃ represent a hydrogen atom or an alkyl group. m and n may be the same as or different from each other. R ₁ , R ₂ , and R ₃ may be the same as or different from each other. _{R 1} and R ₂ may be bonded to each other to form a ring.

An example of a polymer in which R ₁ , R ₂ , and R ₃ are all hydrogen atoms is "TOPAS (registered trademark)" manufactured by Polyplastics Co., Ltd. Furthermore, an example of a polymer in which R ₁ and R ₂ are alkyl groups and R ₃ is a hydrogen atom is "APEL (registered trademark)" manufactured by Mitsui Chemicals, Inc.

These cyclic olefin resins have excellent water vapor barrier properties and are easily available. As described above, in the bag body 10, the sheet member 100 can use these cyclic olefin polymers as the amorphous polymer that is the main component of the innermost layer 101. The innermost layer 101 may contain one type of cyclic olefin resin, or two or more types of cyclic olefin resins.

Here, the two or more types of cyclic olefin polymers may be two or more types of cyclic olefin polymers corresponding to any one of the above formulas (I) to (III), or may be one or more types of cyclic olefin polymers for each of two or more formulas (I) to (III). The two or more types of cyclic olefin polymers may further include cyclic olefin polymers that do not correspond to the above formulas (I) to (III).

Commercially available cyclic olefin polymers include, but are not limited to, ZEONEX (registered trademark) (manufactured by Zeon Corporation, a hydrogenated polymer of ring-opening metathesis polymer of norbornene-based monomers), ZEONOR (registered trademark) (manufactured by Zeon Corporation, a copolymer based on the ring-opening polymerization of dicyclopentadiene and tetracyclopentadodecene), TOPAS (registered trademark) (manufactured by Polyplastics Co., Ltd., a copolymer of norbornene and ethylene), APEL (registered trademark) (manufactured by Mitsui Chemicals, Inc., a copolymer of ethylene and tetracyclododecene), and ARTON (registered trademark) (manufactured by JSR Corporation, a cyclic olefin resin containing polar groups made from dicyclopentadiene and methacrylic acid esters).

The innermost layer 101 may contain other resin components in addition to the cyclic olefin-based resin. Examples of other resin components include one or more of polyolefin-based resins such as polyethylene, polypropylene, polybutene, ethylene-α-olefin copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-vinyl acetate copolymer, and ethylene-(meth)acrylic acid ester copolymer; urethane-based resins; rubber-based resins; polyester-based resins; polyester-urethane-based resins; acrylic resins; amide-based resins; styrene-based resins; and silane-based resins. Among these, styrene-based resins include polystyrene, styrene-acrylonitrile copolymer (SAN), and styrene-based elastomers. Among these, it is particularly preferred that the innermost layer 101 contain one or more components, such as styrene-butadiene copolymer, styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene copolymer, styrene-isoprene-styrene block copolymer (SIS), hydrogenated products thereof (e.g., SEBS, SEPS, etc.), and styrene-butadiene random copolymer, in an amount ranging from 0.05 to 20% by mass.

By including other resin components in the innermost layer 101, it is possible to improve the performance desired for containers such as infusion bags, such as improving the impact resistance of the bag body 10 at low temperatures, maintaining transparency immediately after high-pressure steam sterilization, and improving flexibility.

The innermost layer 101 preferably contains only a cyclic olefin polymer as the resin component (it may contain non-resin additives), and may contain 100% by mass of a cyclic olefin polymer (it does not contain any other additives). If it contains the other resin components described above, it is preferable that the innermost layer 101 be primarily composed of a cyclic olefin polymer. That is, the innermost layer 101 preferably contains one type of cyclic olefin polymer or two or more types of cyclic olefin polymers in total at 50% by mass or more, and particularly preferably at 70% by mass or more. If the composition ratio of the cyclic olefin polymer is low and the contents are pharmaceutical, trace components and pharmaceutical components with a high affinity for plastic may be adsorbed, which may result in insufficient storage stability of the contained pharmaceutical component.

The material constituting the innermost layer 101 may contain various additives such as antioxidants, UV absorbers, antistatic agents, lubricants, and antiblocking agents, to improve the appearance of the container, stabilize quality, and provide other required performance, as long as safety and hygiene are not compromised.

The thickness of the innermost layer 101 is 10 to 100 μm, and more preferably 20 to 80 μm. If the thickness of the innermost layer 101 is 10 μm or more, the innermost layer 101 will have sufficient sealing properties and sufficient welding strength with the port member 20. On the other hand, if the innermost layer 101 is too thin, the innermost layer 101 will thin due to heat and pressure when welding the port member 20 to the openings 13A and 13B, which may result in pinholes that could allow the contents stored in the storage chamber 12 to leak through the pinholes. If the thickness of the innermost layer 101 is 100 μm or less, the flexibility of the bag body 10 will be more easily maintained and manufacturing costs will be reduced.

((adhesive resin layer))
The adhesive resin layer 102 is provided between the innermost layer 101 and the base resin layer 103 to bond the innermost layer 101 and the base resin layer 103 together.

Any commonly used adhesive resin layer may be used as the adhesive resin layer 102, such as an adhesive resin composition containing resin components consisting of linear low-density polyethylene (LLDPE), a styrene (St)-based elastomer, and a polypropylene (PP)-based resin, in which the mass ratio of the LLDPE content to the total content of the St-based elastomer and PP-based resin (LLDPE:(St-based elastomer + PP-based resin)) is within the range of 40:60 to 95:5. Specific examples of adhesive resin layer 102 include "ADMER (registered trademark)" manufactured by Mitsui Chemicals, Inc. and "MODIC (registered trademark)" manufactured by Mitsubishi Chemical Corporation.

The polypropylene used in the adhesive resin layer 102 is produced using a Ziegler-Natta catalyst or a metallocene catalyst. Syndiotactic polypropylene produced using a metallocene catalyst is preferred due to its excellent flexibility and transparency. The polypropylene preferably has a melting peak temperature of 110°C or higher, preferably 120°C or higher. Using polypropylene with these temperature characteristics in the adhesive resin layer 102 imparts heat resistance to the bag body 10.

((Base resin layer))
The base resin layer 103 is a layer located on the outside of the bag body 10, and examples of materials that can be used to form the base resin layer 103 include PP-based resins and polyethylene (PE)-based resins.

The PP-based resin may be a propylene homopolymer, a copolymer obtained by copolymerizing a small amount (e.g., 10% by mass or less) of an α-olefin such as ethylene or 1-butene, or a copolymer produced by multi-stage polymerization of propylene and an α-olefin. Compounds of the above homopolymers or copolymers with other polyolefins or resins may also be used. To improve the flexibility of the sheet member 100, the PP-based resin preferably has a flexural modulus of 400 to 600 MPa. Furthermore, the PP-based resin preferably has a melt flow rate (MFR) of 1 to 4 g/10 min at 230°C and 21.2 N. Furthermore, the PP-based resin preferably has a peak melting temperature of 160 to 170°C. Specific examples of PP-based resins include XELAS (registered trademark) manufactured by Mitsubishi Chemical Corporation.

As the PE resin, low-density polyethylene (LDPE) or linear low-density polyethylene (linear low-density polyethylene (LLDPE)) is preferably used. The density of the polyethylene is preferably in the range of 0.880 to 0.920 g/ ^cm3 . The α-olefin has 12 or fewer carbon atoms, and examples thereof include propylene, butene-1, hexene-1, 4-methylpentene-1, and octene-1. The linear low-density polyethylene is preferably produced using a metallocene catalyst. Linear low-density polyethylene polymerized using a metallocene catalyst has little structural heterogeneity and is therefore excellent in transparency. Furthermore, since the molecular weight distribution is nearly uniform, when the LLDPE is heated, the polyethylene produces little bleeding and is less likely to become cloudy.

The polypropylene used in the base resin layer 103 is produced using a Ziegler-Natta catalyst or a metallocene catalyst. Syndiotactic polypropylene produced using a metallocene catalyst is preferred due to its excellent flexibility and transparency. The polypropylene preferably has a melting peak temperature of 110°C or higher, preferably 120°C or higher. Using polypropylene with these temperature characteristics in the base resin layer 103 imparts heat resistance to the bag body 10.

(Other layers)
The sheet member 100 may optionally include other layers between or on the surface of either the innermost layer 101 or the base resin layer 103. The types of other layers can be appropriately selected, and examples thereof include a reinforcing layer, a printed layer, a coating layer, a light-shielding layer, a vapor-deposited layer, a metal foil, and synthetic paper.

Examples of reinforcing layers include reinforcing resin layers such as biaxially oriented polyethylene terephthalate (O-PET), biaxially oriented nylon (O-Ny), and biaxially oriented polypropylene (OPP).

The printed layer or coating layer may be provided on the surface (front surface) 103a of the base resin layer 103 opposite the adhesive resin layer 102.

The printing layer can impart distinctiveness and design to the drug solution bag 1 by printing ink on the surface 103a of the base resin layer 103.

The coating layer is intended to protect the base resin layer 103 or other layers, such as a printed layer, provided on the base resin layer 103. Examples of such coating layers include a thin resin layer (resin film) and an ultraviolet-curable resin layer.

As described above, the joint 11 is formed by overlapping a pair of sheet members 100 facing each other with the port member 20 sandwiched between them.

The first joint 11-1 of the joint 11 is formed by fusing together the resins contained in the innermost layers 101 of the pair of sheet members 100. The first joint 11-1 has a layered structure in which the layers are stacked in the following order from the surface side of one base resin layer 103 of the sheet members 100 toward the surface side of the other base resin layer 103: base resin layer 103/adhesive resin layer 102/innermost layer 101/innermost layer 101/adhesive resin layer 102/base resin layer 103.

The second joint 11-2 is formed by fusing together the resin contained in the innermost layer 101 of each of the pair of sheet members 100 and the port member 20. The second joint 11-2 has a layered structure in which the layers are stacked in the following order from the surface side of one base resin layer 103 of the sheet members 100 toward the surface side of the other base resin layer 103: base resin layer 103 / adhesive resin layer 102 / innermost layer 101 / port member 20 / innermost layer 101 / adhesive resin layer 102 / base resin layer 103.

[Port member]
As shown in Figure 2, the port member 20 is sandwiched and welded between opposing innermost layers 101 of the sheet member 100 that constitutes the bag body 10. The port member 20 has a substantially cylindrical shape and includes a flow path 21 large enough to allow the flow of contents stored in the storage chamber 12. At least a portion of the port member 20 may be contained within the storage chamber 12, with one end 20a of the port member 20 communicating with the storage chamber 12 and an opening 22 at the other end 20b exposed to the outside of the bag body 10. The shape of the port member 20 as viewed in the axial direction may be a shape other than cylindrical, and may be, for example, a polygonal shape such as a square or hexagon, or an elliptical shape.

The port member 20 may contain a port material, preferably consist essentially of the port material, and more preferably consist entirely of the port material. Note that "substantially" means that the port member 20 may contain impurities that are unavoidably mixed in during its manufacture. The port member 20 is obtained by molding a port-forming composition containing the port material into a cylindrical shape. When the port member 20 is made of the port material, the port member 20 is obtained by molding the port material.

The seal strength (hereinafter simply referred to as "seal strength") of the port material contained in the port member 20 to a substrate containing a cyclic olefin is 30 N/15 mm or more, preferably 35 N/15 mm or more, more preferably 40 N/15 mm or more, and even more preferably 50 N/15 mm or more. The upper limit of the seal strength of the port material may be 70 N/15 mm or less. Even if the innermost layer 101 contains an amorphous polymer having a cyclic hydrocarbon skeleton such as a cyclic olefin as its main component, the port member 20 formed using the port material can have high adhesion to the innermost layer 101 of the sheet member 100 as long as the seal strength of the port material is 30 N/15 mm or more.

Seal strength can be measured in accordance with ASTM F88. For example, a laminate is produced by heat-sealing a port sheet made of port material to a substrate such as a resin film having, on its outermost surface, a layer (COP layer) containing a polymer (cycloolefin polymer; COP) made of one or more cyclic olefins such as norbornene. The seal strength can be determined by measuring the strength when the produced laminate is peeled off at a specified tensile speed (e.g., 300 mm/min).

The tensile modulus of the port material is preferably 20 to 70 MPa. The lower limit of the tensile modulus is more preferably 25 MPa or more, and even more preferably 27 MPa or more. The upper limit of the tensile modulus is more preferably 65 MPa or less, and even more preferably 62 MPa or less. When the tensile modulus is within the above preferred range, the port member 20 formed using the port material is highly flexible and easily deformed, thereby reducing damage to the port member 20 due to bending and facilitating liquid stoppage by crushing the port member 20. Furthermore, a predetermined length of the port member 20 can be easily peeled off from the wound-up state during manufacturing. Furthermore, when a connector member or the like is connected to the tube tip of the port member 20 on the side opposite the second joint 11-2, adhesion with the connector member or the like can be maintained.

The tensile modulus can be measured in accordance with ISO 527-3:2018. For example, a sheet-shaped sample is prepared using the port material, and then cut to a specified size to prepare a rectangular test piece. The cut-out test piece can be pulled at a pulling rate (e.g., 300 mm/min) and the tensile modulus of the port material can be calculated from the slope of the graph in the range of 10 to 20 N.

The melt mass flow rate (MFR) of the port material at 190°C is preferably 3.8 to 20 g/10 min. The lower limit of the MFR at 190°C is more preferably 3.9 g/10 min or more, and even more preferably 4.5 g/10 min or more. The upper limit of the MFR at 190°C is more preferably 15 g/10 min or less, and even more preferably 13 g/10 min or less. If the MFR at 190°C is within the above preferred range, the extrusion moldability of the port material is improved, making it easier to mold and produce the port member 20.

The MFR at 190°C can be measured in accordance with JIS K 7210-1:2014. For example, a sheet-like sample is prepared using the port material, and then the prepared sample is cut to a specified size to prepare a rectangular test specimen. The cut-out test specimen is placed in a cylinder at a specified temperature (190°C) connected directly below a die, and pressed down with a piston. Preheating is performed at 190°C for 6 minutes. After preheating, the temperature is returned to 190°C, and a specified weight (2.16 kg) is placed on the piston to extrude the molten test specimen through the die. The mass of the extruded test specimen at the specified extrusion time is measured, and the mass per 10 minutes [g/10 min] is calculated to determine the MFR at 190°C. Instead of a cut-out sheet sample, the port material may be pelletized (powdered) and weighed out in the required amount to be used as the test specimen.

The port material used to form the port member 20 preferably contains a polyolefin resin.

Polyolefin resins may be homopolymers of one type of olefin or copolymers of two or more types of olefins. Examples of olefins include acyclic olefins such as ethylene, propylene, 1-butene, 1-hexene, 1-octene, and α-olefins. Specific examples of polyolefins include polyethylene, polypropylene, and ethylene-α-olefin copolymers. These polyolefins may also be copolymers containing small amounts of non-olefin vinyl monomers such as vinyl acetate, vinyl chloride, and vinyl alcohol. The olefins may be derived from petroleum-derived olefins, plant-derived olefins, or a combination of both.

When the polyolefin resin used for the port material is polyethylene, linear low-density polyethylene (LLDPE) is preferred. If the port material is LLDPE, the port member 20 is formed from LLDPE. When the port member 20 is formed from LLDPE, the sheet member 100 that forms the bag body 10 and the port member 20 can be more easily joined, and the adhesion between the sheet member 100 and the port member 20 is increased.

The port material may be formed from one or more types of LLDPE.

The port material preferably contains LLDPE and a resin with a tensile modulus of elasticity of 25 MPa or less.

Examples of resins with a tensile modulus of elasticity of 25 MPa or less include LLDPE, styrene (St)-based elastomers, and olefin-based elastomers.

Examples of St-based elastomers include St-based thermoplastic elastomers.

Examples of St-based thermoplastic elastomers include styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-isoprene-styrene block copolymer (SIS), styrene-butadiene-styrene block copolymer (SBS), styrene-ethylene-propylene-styrene block copolymer (SEPS), and styrene-ethylene-ethylene-propylene-styrene block copolymer (SEEPS). Of these, SEBS is preferred.

The mass ratio of the LLDPE content to the resin content having a tensile modulus of 25 MPa or less is preferably 60:40 to 75:25, more preferably 60:40 to 75:25, and even more preferably 60:40 to 75:25. When the LLDPE and resin having a tensile modulus of 25 MPa or less are contained in the above preferred ratio, the port material is likely to exhibit both flexibility and moldability.

When the port member 20 is made of two different types of LLDPE, it is preferable that the MFR at 190°C of one of the two different types of LLDPE is higher than the MFR at 190°C of the other LLDPE, and that the flexural modulus of the other LLDPE is lower than the flexural modulus of the one LLDPE. This allows the port material to maintain a good balance between flexibility and moldability.

The MFR of one of the LLDPEs at 190°C is preferably 8 g/10 min or more, more preferably 10 g/10 min or more, and even more preferably 12 g/10 min or more.

The flexural modulus of the other LLDPE is preferably 100 MPa or less, more preferably 80 MPa or less, and even more preferably 70 MPa or less.

Note that the definitions of "one" and "the other" for linear low-density polyethylene (LLDPE) in terms of MFR and "one" and "the other" for linear low-density polyethylene (LLDPE) in terms of flexural modulus are the same. Therefore, for example, "one LLDPE" in terms of MFR and "one LLDPE" in terms of flexural modulus refer to the same LLDPE.

In addition to the port member 20, the drug solution bag 1 may also have accessories such as an injection port, a cock, a label, an opening knob, and a handle. If the accessories are molded from resin, they may have the same configuration as the port member 20 described above.

[Method of manufacturing a drug solution bag]
The chemical solution bag 1 can be manufactured using a general manufacturing method for chemical solution bags. An example of the manufacturing method for the chemical solution bag 1 will be described. In the manufacturing method for the chemical solution bag 1, a resin that is a raw material for the innermost layer 101, a resin that is a raw material for the adhesive resin layer 102, and a resin that is a raw material for the base resin layer 103 are laminated in this order to form a sheet member 100 in which the innermost layer 101, the adhesive resin layer 102, and the base resin layer 103 are laminated in this order (sheet member forming process).

The sheet member 100 may be formed by laminating the resin that will be used as the raw material for the innermost layer 101, the resin that will be used as the raw material for the adhesive resin layer 102, and the resin that will be used as the raw material for the base resin layer 103 using a method such as dry lamination or extrusion lamination.

Next, the port member 20 is produced by molding the port-forming composition containing the port material into a cylindrical shape such as a cylinder (port member forming process).

Next, the pair of sheet members 100 and the port member 20 are joined together (joining process).

First, the innermost layers 101 of a pair of sheet members 100 are stacked facing each other, and the port member 20 is sandwiched between the sheet members 100.

Next, the pair of sheet members 100 and the port member 20 are joined to form the second joint 11-2.

Next, the pair of sheet members 100 are joined together to form the first joint 11-1.

This completes the production of the drug solution bag 1.

As such, the drug solution bag 1 comprises a bag body 10 and a port member 20. The sheet member 100 constituting the bag body 10 includes an innermost layer 101 and a base resin layer 103. The innermost layer 101 contains an amorphous polymer having a cyclic hydrocarbon skeleton as its main component, and the port material contained in the port member 20 has a seal strength of 30 N/15 mm or greater. Because the innermost layer 101 of the sheet member 100 contains an amorphous polymer having a cyclic hydrocarbon skeleton as its main component, it is resistant to radiation. Furthermore, because the port member 20 is formed using a port material with a seal strength of 30 N/15 mm or greater, the port member 20 can achieve enhanced adhesion with the sheet member 100. Therefore, the drug solution bag 1 can achieve enhanced adhesion between the bag body 10 and the port member 20 while also exhibiting excellent resistance to radiation.

Furthermore, in the drug solution bag 1, deterioration of the innermost layer 101 is suppressed even when sterilized using radiation, which prevents a decrease in the adhesive strength between the bag body 10 and the port member 20. Therefore, the drug solution bag 1 can maintain adhesion between the bag body 10 and the port member 20, thereby preventing the elution of the contents within the bag body 10.

In the drug solution bag 1, the port material contained in the port member 20 preferably has a tensile modulus of elasticity of 20 to 70 MPa. A port member 20 formed using this port material can increase flexibility, thereby further improving the adhesion between the bag body 10 and the port member 20.

In particular, commercially available tube ports are generally manufactured by extrusion molding, and it is important for the port member to be flexible in order to ensure adhesion to the molded product, such as the bag body 10 to which the port member is connected, and to seal the port member by pressing and crushing it. By increasing the flexibility of the port member 20 formed using a port material, the port member 20 can be pressed and crushed to seal it against the innermost layer 101 of the bag body 10, thereby further improving the airtightness of the drug solution bag 1.

In the drug solution bag 1, the port material contained in the port member 20 preferably has an MFR at 190°C of 3.8 to 20 g/10 min. This allows the port material to have improved moldability, particularly extrusion moldability, so that the port member 20 formed using this port material is easier to manufacture, has reduced surface irregularities, and has a good appearance. This makes it less likely for gaps to form between the innermost layer 101 of the sheet member 100 and the port member 20 at the openings 13A and 13B of the bag body 10, allowing for more reliable adhesion. Therefore, the drug solution bag 1 can further improve the adhesion between the bag body 10 and the port member 20.

In the drug solution bag 1, the port material contained in the port member 20 preferably contains one or more types of LLDPE. A port member 20 formed using this port material is easier to bond to the sheet member 100 that forms the bag body 10, improving adhesion to the bag body 10. As a result, the drug solution bag 1 can more reliably improve the sealing of the storage chamber 12 and improve durability.

In the drug solution bag 1, the port material contained in the port member 20 is preferably formed from a material containing LLDPE and a resin with a tensile modulus of elasticity of 25 MPa or less. This makes it easier for the port member 20 to maintain both flexibility and formability, and therefore makes it easier for the drug solution bag 1 to improve adhesion between the bag body 10 and the port member 20.

In the drug solution bag 1, the port material contained in the port member 20 preferably has a mass ratio of LLDPE content to resin content with a tensile modulus of 25 MPa or less of 60:40 to 75:25. This makes it easier for the port member 20 formed using this port material to maintain both flexibility and formability, making it easier to further improve the adhesion between the bag body 10 and the port member 20 in the drug solution bag 1, thereby improving quality.

In the drug solution bag 1, the port material contained in the port member 20 includes two different types of LLDPE, and it is preferable that the MFR at 190°C of one of the two different types of LLDPE is higher than the MFR at 190°C of the other LLDPE, and that the tensile modulus of the other LLDPE is higher than the tensile modulus of the one LLDPE. This allows the port member 20 to have a balanced improvement in both flexibility and moldability, thereby improving the adhesion between the bag body 10 and the port member 20 in the drug solution bag 1.

In the drug solution bag 1, it is preferable that the MFR at 190°C of one of the LLDPEs contained in the port material of the port member 20 is 8 g/10 min or more, and the tensile modulus of elasticity of the other LLDPE is 100 MPa or less. This allows the port member 20 to have a balanced improvement in both flexibility and formability, thereby improving the adhesion between the bag body 10 and the port member 20 in the drug solution bag 1.

Note that the definitions of "one" and "the other" for LLDPE in terms of MFR and "one" and "the other" for LLDPE in terms of flexural modulus are the same.

As described above, due to the properties of the medicinal solution bag 1, it can be suitably used as an infusion bag that contains medicines (drugs), nutrients, food, beverages, etc. and is subjected to sterilization. Examples of medicines include low-molecular-weight medicines and biopharmaceuticals. The medicinal solution bag 1 can be particularly effectively used as an infusion bag that contains biopharmaceuticals.

Although the embodiments have been described above, they are presented as examples and the present invention is not limited to these embodiments. The embodiments can be implemented in a variety of other forms, and various combinations, omissions, substitutions, modifications, etc. are possible without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention, as well as within the scope of the inventions and their equivalents as set forth in the claims.

The present embodiment will be explained in more detail below using examples, but the present embodiment is not limited to these examples. Note that Examples 1 to 9, 12 to 16, 19 to 26, and 29 are working examples, and the other examples are comparative examples.

<Examples 1 to 30>
[Preparation of port formation sheet]
Resin pellets serving as port materials were prepared using one or two of the resins listed in Table 1 below. When a single port material was used, the port material was melted and processed into pellets to produce the resin pellets. When two resins were used, the two resins (Resin 1 and Resin 2) were mixed, melted in an extruder, kneaded, and processed into pellets to produce the resin pellets. The prepared resin pellets were melt-pressed using a hot press at a set temperature of 190°C and a press pressure of 15 MPa, then cooled to produce port-forming sheets with thicknesses of 0.6 to 0.75 mm. The type and physical properties of the resins used to prepare each resin pellet are listed in Table 1. The type and ratio of the resin pellets used to prepare the port-forming sheets are listed in Table 2. In Table 2, when a port material is made of a single resin, it is indicated as "Resin 1" or "Resin 2." When a port material is made of a mixture of two resins, one resin is indicated as "Resin 1" and the other as "Resin 2."

The resins used in Table 1 are as follows:
LLDPE1: Metallocene-based linear low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd.)
LLDPE2: Metallocene-based linear low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd.)
LLDPE3: Metallocene-based linear low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd.)
LLDPE4: Metallocene-based linear low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd.)
LLDPE5: Metallocene-based linear low-density polyethylene (manufactured by Tosoh Corporation)
LLDPE6: Metallocene-based linear low-density polyethylene (manufactured by Japan Polyethylene Co., Ltd.)
LLDPE7: Metallocene-based linear low-density polyethylene (manufactured by Tosoh Corporation)
LLDPE8: Metallocene-based linear low-density polyethylene (manufactured by Tosoh Corporation)
Styrene-based elastomer: styrene-ethylene-butylene-styrene block copolymer (Kraton (registered trademark) G (styrene content 13% by mass, specific gravity 0.90 g/cm ³ , MFR=22 g/10 min (230° C., 5 kgf)), manufactured by Kraton Polymer Japan Co., Ltd.)
PP: MF800, manufactured by Renolit Co., Ltd. HDPE: High-density polyethylene (manufactured by Tosoh Corporation)

[Evaluation of port formation sheets]
The properties of the produced port-forming sheets were evaluated, including MFR at 190°C, tensile modulus, seal strength, and radiation resistance. The measurement results for each property are shown in Table 3. Note that the values shown in gray in Table 3 satisfy or are preferable for this embodiment.

(MFR at 190°C)
In accordance with JIS K 7210, a port-forming sheet was cut to a predetermined size to prepare rectangular test specimens. The cut test specimen was placed in a cylinder at a specified temperature (190°C) connected directly below a die, pressed down with a piston, and preheated at 190°C for 6 minutes. After preheating, a specified weight (2.16 kg) was placed on the piston at 190°C, and the molten test specimen was extruded through the die. The mass of the extruded test specimen at the specified extrusion time was measured. The MFR at 190°C was determined by calculating the mass per 10 minutes [g/10 min]. When the MFR of the port-forming sheet at 190°C was 3.8 to 20 g/10 min, the MFR at 190°C was evaluated as good.

(Tensile modulus)
According to ISO 527-3:2018, the port-forming sheet was cut to a predetermined size (15 mm wide x 70 mm long) to prepare rectangular test specimens. The cut test specimens were pulled at a pulling rate of 300 mm/min, and the tensile modulus of the port-forming sheet was calculated from the slope of the graph in the range of 10 to 20 N. A port-forming sheet with a tensile modulus of 20 to 70 MPa was evaluated as having a good tensile modulus.

(Seal strength)
In accordance with ASTM F88, a port-forming sheet and a resin film (resin film composition: PP (thickness 150 μm)/adhesive resin layer (AD) (thickness 65 μm)/COP (thickness 25 μm)) were heat-sealed under the following heat-sealing conditions to produce a laminate. The produced laminate was cut to a predetermined size (width 15 mm x length 70 mm) to prepare rectangular test pieces. The port-forming sheet and resin film of the cut test pieces were peeled apart at a tensile speed of 300 mm/min, and the strength was measured as the seal strength. A port-forming sheet with a seal strength of 30 N/15 mm or more was evaluated as having good seal strength.
*Heat sealing temperature: 240℃
Time: 3sec
Pressure: 0.2 MPa

In Examples 22 to 25 (examples with an "*" next to the numerical values in Table 3), resin pellets made from the resins shown in Table 1 were used instead of a port-forming sheet. A cylindrical port member (inner diameter: 6 mm, outer diameter: 8 mm, cylindrical wall thickness: 1 mm) was extrusion molded into a tubular shape, and the seal strength was measured using this.

(Radiation resistance)
The port-forming sheet was irradiated with gamma rays at a sterilization dose of 25 kGy, and the port-forming sheet was visually inspected for yellowing and evaluated based on the following criteria: If the port-forming sheet did not yellow upon gamma-ray irradiation, the port-forming sheet was evaluated as having good radiation resistance and suitable for radiation sterilization.
*Evaluation criteria A: The port formation sheet did not turn yellow. B: At least a part of the port formation sheet turned yellow.

Table 3 shows that the port-forming sheets of Examples 1 to 9, 12 to 16, 19 to 26, and 29 had a seal strength of 25.4 N/15 mm or more and were also resistant to radiation (see the gray areas in Table 3).

Furthermore, of the port-forming sheets in the above examples, the port-forming sheets other than those in Examples 15, 16, 22, and 25 had an MFR of 3.9 g/10 min or more at 190°C (see the gray areas in Table 3).

Furthermore, of the port-forming sheets in Examples 1 to 9, 12 to 16, 19 to 26, and 29 above, the tensile modulus of elasticity of the port-forming sheets other than Examples 8, 9, 12 to 15, and 19 to 26 was approximately 61 MPa or less (see the gray areas in Table 3).

On the other hand, the port-forming sheets in Examples 1 to 9, 12 to 16, 19 to 26, and 29 above had a seal strength with the cyclic olefin of 27.4 N/15 mm or less. Furthermore, the port-forming sheet in Example 28 was not resistant to radiation because PP was used to form the port-forming sheet.

Therefore, if the port member (tube port) of a drug solution bag is manufactured using the port material constituting the port formation sheets of Examples 1 to 9, 12 to 16, 19 to 26, and 29 above, the port member can exhibit the same effects. Therefore, drug solution bags equipped with port members manufactured using the port materials used in Examples 1 to 9, 12 to 16, 19 to 26, and 29 above can exhibit excellent resistance to radiation while improving adhesion between the bag body and the port member.

1...medicinal solution bag, 10...bag body, 11...joint (sealing portion), 12...storage chamber, 13A, 13B, 22...opening, 20...port member (tube port), 100...sheet member, 101...innermost layer (sealing layer), 102...adhesive resin layer (AD), 103...base resin layer

Claims (9)

A drug solution bag having a bag body that accommodates contents and a cylindrical port member attached to the bag body,
The bag body is formed by molding a sheet member into a bag shape,
the sheet member includes an innermost layer and a base resin layer, the innermost layer containing an amorphous polymer having a cyclic hydrocarbon skeleton as a main component,
the port member includes a port material;
A drug solution bag, wherein the port material has a seal strength of 30 N/15 mm or more with respect to a substrate containing a cyclic olefin. The drug solution bag according to claim 1, wherein the port material has a tensile modulus of elasticity of 20 to 70 MPa. The drug solution bag according to claim 1 or 2, wherein the port material has an MFR of 3.8 to 20 g/10 min at 190°C. The drug solution bag according to any one of claims 1 to 3, wherein the port material contains one or more linear low-density polyethylenes. The drug solution bag according to any one of claims 1 to 4, wherein the port material contains linear low-density polyethylene and a resin having a tensile modulus of elasticity of 25 MPa or less. The drug solution bag according to claim 5, wherein the mass ratio of the content of the linear low-density polyethylene to the content of the resin having a tensile modulus of elasticity of 25 MPa or less is 60:40 to 75:25. the port material comprises two different types of linear low density polyethylene;
one of the two different linear low-density polyethylenes has a higher MFR at 190°C than the other linear low-density polyethylene;
7. The drug solution bag according to claim 1, wherein the other linear low-density polyethylene has a lower flexural modulus than the one linear low-density polyethylene. the MFR of the one linear low-density polyethylene at 190°C is 8 g/10 min or more;
8. The drug solution bag according to claim 7, wherein the other linear low-density polyethylene has a flexural modulus of elasticity of 100 MPa or less. The drug solution bag according to any one of claims 1 to 8, wherein the contents are a medicine.