JP7570665B2 - Film rolls for packaging fruits and vegetables, and packaging bags for preserving the freshness of fruits and vegetables - Google Patents

Description

The present invention relates to a packaging bag for preserving the freshness of fruits and vegetables, and a packaging film roll used to form the packaging bag for preserving the freshness of fruits and vegetables.

As packaging bags for packaging various kinds of fruits and vegetables, such as leafy vegetables, fruit vegetables, root vegetables, fruits, and fungi, there are known packaging bags made of synthetic resin film, such as two-sided bags, three-sided bags, folded bags, pouches, and gusset bags. Furthermore, such packaging bags made of synthetic resin film are often formed by overlapping two sheets of synthetic resin film (or folding a single synthetic resin film) and heat sealing (thermal bonding) the outer periphery. Therefore, from the viewpoint of ease of heat sealing (ability to heat seal at a relatively low temperature), packaging bags made of polyolefin resin film are widely used (Patent Document 1).

In addition, packaging bags made of polyolefin resin film have low water vapor permeability, so when fruits and vegetables, which emit a lot of water vapor, are packaged and sealed, water droplets form on the inside of the film, causing it to become cloudy and degrading its appearance. Therefore, bags with fine holes or slits to adjust the water vapor permeability have been developed.

Packaging bags made of polyolefin resin film as described above are usually continuously manufactured using a film roll made by winding a long synthetic resin film of a fixed width. In addition, packaging bags containing fruits and vegetables can also be continuously manufactured by so-called automatic filling and packaging, in which bags are made from a film roll and filled with fruits and vegetables at the same time.

JP 2004-284654 A

However, when continuously manufacturing packaging bags made of polyolefin resin film with fine holes or slits, depending on how the fine holes or slits are formed, uneven edges due to misalignment of the winding or blocking due to tight winding can occur during production, making it impossible to efficiently manufacture bags with a good yield. This tendency is particularly noticeable when fruit and vegetables are automatically packed and packaged, or when using film rolls made of synthetic resin film with anti-fogging properties.

The object of the present invention is to provide a film roll for packaging fruits and vegetables that solves the problems of the above-mentioned conventional packaging bags for preserving the freshness of fruits and vegetables, and that can be efficiently manufactured with a high yield without causing uneven edges due to misalignment in the winding or blocking due to tight winding. It is also to provide a packaging bag for preserving the freshness of fruits and vegetables that can be manufactured inexpensively and easily, and has excellent freshness preservation properties.

Among the present inventions, the invention described in claim 1 is a film roll formed by winding a long synthetic resin film used in the automatic filling and packaging of fresh produce, which automatically fills the fresh produce and at the same time forms a freshness-preserving packaging bag, wherein a ventilation section for promoting air circulation between the front and back is formed by drilling one or more holes at a predetermined interval in the synthetic resin film, and the air evacuation index of the part of the synthetic resin film centered on the ventilation section is 3,000 seconds or more and 55,000 seconds or less, and the freshness-preserving packaging bag is a hand-folded bag formed by folding the left and right sides of the synthetic resin film and joining the left and right ends in the center and heat-sealing them to a predetermined width to form a back seam, and wherein the ventilation section is formed at a position adjacent to the back seam in the vertical center of the hand-folded bag to be formed .

The invention described in claim 2 is the invention described in claim 1, characterized in that the hole serving as the ventilation section is 0.05 mmφ or more and less than 8.0 mmφ.

The invention described in claim 3 is the invention described in claim 1 or claim 2, characterized in that an anti-fogging agent is present on the surface that will become the inside of the freshness-preserving packaging bag after automatic filling of the synthetic resin film.

The invention described in claim 4 is a packaging bag for preserving the freshness of fruits and vegetables, formed by automatically filling fruits and vegetables with the film roll for automatic filling and packaging of fruits and vegetables described in any one of claims 1 to 3.

The film roll for packaging fruits and vegetables according to the present invention (hereinafter simply referred to as the film roll) can efficiently produce freshness-preserving packaging bags for fruits and vegetables with good yields without causing unevenness in the end faces (mainly the end faces in the width direction) due to misalignment in winding or blocking due to tight winding. In addition, when the film roll according to the present invention is used in automatic filling and packaging of fruits and vegetables (a packaging form in which freshness-preserving packaging bags are formed while filling the fruits and vegetables (simultaneously)), it becomes possible to perform automatic filling and packaging of fruits and vegetables smoothly and efficiently with good yields.

Furthermore, the packaging bag for preserving the freshness of fruits and vegetables (hereinafter simply referred to as the packaging bag) formed by the film roll according to the present invention can be produced inexpensively and easily, has excellent freshness preservation properties, and is suitable for packaging fruits and vegetables such as edamame and broccoli, which are prone to mold growth and discoloration in excessively humid conditions.

FIG. 1 is an explanatory diagram showing a state in which fruits and vegetables are automatically packed using a film roll. FIG. 11 is an explanatory diagram showing a state in which a ventilation portion is formed at one end of a film roll. FIG. 2 is an explanatory diagram (rear view) showing a packaging bag containing fresh produce. FIG. 11 is an explanatory diagram showing how a ventilation portion is formed at one end of a film roll. FIG. 2 is an explanatory diagram (rear view) showing a packaging bag containing fresh produce. FIG. 2 is an explanatory diagram (rear view) showing a packaging bag containing fresh produce. FIG. 2 is an explanatory diagram (rear view) showing a packaging bag containing fresh produce. FIG. 2 is an explanatory diagram (rear view) showing a packaging bag containing fresh produce. FIG. 2 is an explanatory diagram (rear view) showing a packaging bag containing fresh produce.

The film roll for packaging fruits and vegetables according to the present invention (hereinafter, simply referred to as the film roll) is made by winding a long synthetic resin film of a certain width, and the synthetic resin film has a ventilation section formed therein to promote air circulation between the front and back at a specified cycle. Furthermore, the air evacuation index of the synthetic resin film starting from the ventilation section (i.e., the air evacuation index of the part of the synthetic resin film centered on the ventilation section) is adjusted to 3,000 seconds or more and 55,000 seconds or less (the method for measuring the air evacuation index will be described later). By using a film roll with the above characteristics, it becomes possible to make bags and automatically fill and package fruits and vegetables without causing uneven edges due to winding slippage or blocking due to winding tightening. It is more preferable that the air evacuation index of the synthetic resin film is 20,000 seconds or more and 53,000 seconds or less.

As the synthetic resin film for forming the film roll according to the present invention, a general-purpose synthetic resin film that can be heat-sealed or melt-cut sealed, such as a polyolefin film or a polyester film, can be suitably used. Among these, it is preferable to use a biaxially oriented polypropylene film, a polyethylene terephthalate film, or a polylactic acid film, since the transparency of the film roll is high and it is easy to see the inside when fruits and vegetables are packaged inside.

The synthetic resin film may be a single layer, or may have a multi-layer structure in which a heat-sealing layer or the like is laminated on a base layer. However, it is also possible to use a laminate film formed by laminating melt-extruded polyethylene as a heat-sealing layer on a biaxially oriented polyethylene terephthalate film, which is a base layer, as the synthetic resin film.

The thickness of the synthetic resin film, which is the material used for the formation, is not particularly limited, but is preferably in the range of 5 to 75 μm, and more preferably in the range of 20 to 50 μm. If the thickness of the synthetic resin film is less than 5 μm, the film will lose its stiffness, making it difficult to make bags and automatically fill and package fruits and vegetables, and the packaging bags after packaging the fruits and vegetables will have no volume and will be difficult to handle, which is undesirable. On the other hand, if the thickness of the synthetic resin film exceeds 75 μm, the film will be too rigid, making it difficult to make bags and automatically fill and package fruits and vegetables, and making it difficult to seal the bags after packaging the fruits and vegetables, which is undesirable.

The film roll according to the present invention can also be used to package various fruits and vegetables (including those that are prone to mold growth and discoloration due to vigorous breathing when the inside of the bag becomes overhumid, such as edamame and broccoli), and in order to maintain good freshness, it is preferable that one side of the synthetic resin film that will become the inner surface of the final packaging bag (hereinafter referred to as the packaging side) has anti-fogging properties. There are no particular limitations on the method of imparting anti-fogging properties, but an anti-fogging agent may be incorporated in advance into the synthetic resin raw material that forms the synthetic resin film, or the packaging side of the synthetic resin film may be coated with an anti-fogging agent. Examples of anti-fogging agents used here include non-ionic surfactants, and it is preferable to use one that exhibits antistatic properties in addition to anti-fogging properties.

Such anti-fogging agents include non-ionic surfactants such as fatty acid esters of polyhydric alcohols, amines of higher fatty acids, amides of higher fatty acids, sucrose fatty acid esters, and ethylene oxide adducts of amines or amides of higher fatty acids. Among these anti-fogging agents, it is preferable to use polyoxyethylene alkylamine type, polyoxyethylene alkylamine fatty acid ester type, and fatty acid glycerin ester type in combination. It is also possible to use water-soluble resins such as polyvinyl alcohol as a coating agent.

In addition, the resin forming the synthetic resin film may contain additives such as heat stabilizers, antioxidants, light stabilizers, lubricants, nucleating agents, flame retardants, pigments, dyes, calcium carbonate, barium sulfate, magnesium hydroxide, mica, talc, clay, zinc oxide, magnesium oxide, aluminum oxide, antibacterial agents, and additives that impart natural decomposition properties, as long as the properties of each layer are not impaired. Furthermore, thermoplastic resins, thermoplastic elastomers, rubbers, hydrocarbon resins, petroleum resins, and the like may be blended in as long as the properties of the synthetic resin film are not impaired, and the synthetic resin film may be subjected to special treatment to control the moisture state within the fruit or vegetable to be packaged.

In addition, the film roll according to the present invention is required to have a ventilation part formed in the synthetic resin film for promoting air circulation between the front and back at a predetermined cycle. By forming such a ventilation part, not only can bag making and automatic filling and packaging of fruits and vegetables be made more efficient, but also the final packaging bag is endowed with a function for adjusting the permeability of water vapor, _CO2, etc., which are necessary for maintaining the freshness of fruits and vegetables.

When the ventilation section is formed by drilling holes in a synthetic resin film, the shape of the hole is not particularly limited, and can be various shapes such as a circle, an ellipse, a rectangle, etc. Furthermore, the method of forming the ventilation section is also not particularly limited, and various methods such as a puncher, a laser, and a needle piercing can be suitably used. Furthermore, the ventilation section is not limited to a pierced state, and may be an unpierced state. Furthermore, when the packaging bag according to the present invention is a so-called gusset bag (a bag with both left and right end edges heat-sealed on the back), it is also possible to form a ventilation section in the packaging bag by forming a non-heat-sealed portion in a part of the back seam (a vertical heat-sealed portion provided vertically in the approximate center of the back).

Furthermore, when the ventilation section is formed by drilling holes in a synthetic resin film, the size of the hole is not particularly limited, but it is preferable that the diameter (φ) is 0.05 mm or more and less than 8.0 mm, since this makes bag making and automatic filling and packaging of fruits and vegetables more efficient and also ensures that the freshness retention properties of the fruits and vegetables in the final packaging bag are very good. The diameter of the hole as the ventilation section is more preferably 0.07 mm or more and less than 6.0 mm, and particularly preferably 0.09 mm or more and less than 4.0 mm. In addition, when the ventilation section is formed by drilling holes in a synthetic resin film, the number of the holes is not particularly limited, and can be adjusted as needed within the range of approximately 1 to 50.

In addition, the film roll according to the present invention has an air release index of the synthetic resin film starting from the ventilation part (the method for measuring the air release index will be described later) adjusted to 3,000 seconds or more and 40,000 seconds or less. The "air release index of the synthetic resin film starting from the ventilation part" refers to the "air release index of the part of the synthetic resin film where the ventilation part is formed", and is obtained by sampling the periphery of the part of the synthetic resin film where the ventilation part is formed (the part within a radius of about 85 mm from the part where the ventilation part is formed) and measuring the air release index of the sample. By adjusting the air release index of the synthetic resin film starting from the ventilation part to a specific numerical range in this way, it becomes possible to make bags and automatically fill and package fruits and vegetables without causing unevenness of the end faces (mainly the end faces in the width direction) due to winding deviation or blocking due to winding tightening.

If the air evacuation index is less than 3,000 seconds, overlapping synthetic resin films will not slide easily against each other during bag making or automatic filling and packaging of fruits and vegetables, which is undesirable as blocking due to tight rolling will occur. Conversely, if the air evacuation index is more than 40,000 seconds, overlapping synthetic resin films will slide too much against each other during bag making or automatic filling and packaging of fruits and vegetables, which is undesirable as misalignment and unevenness of the end faces (mainly the end faces in the width direction) will occur due to misalignment of the winding. It is more preferable for the air evacuation index to be 3,500 seconds or more and 38,000 seconds or less, and it is particularly preferable for the air evacuation index to be 4,000 seconds or more and 35,000 seconds or less.

In addition, the shape of the packaging bag according to the present invention is not particularly limited, and various shapes are possible, such as a three-sided bag made by heat-sealing the left and right sides and the bottom, a two-sided bag made by heat-sealing the left and right sides of a synthetic resin film folded in half, and a two-sided bag made by folding the left and right sides of a film and heat-sealing the back side. The heat-sealing temperature when making the packaging bag can be adjusted as necessary within the range of 80°C or higher and lower than 250°C.

The size of the packaging bag according to the present invention is not particularly limited as long as it is a size suitable for putting fruits and vegetables in, but a size of 100 to 350 mm in width x 150 to 450 mm in height is more suitable for use. If the size of the packaging bag is too small or conversely too large, it is not preferable because it becomes difficult to adjust the permeability of water vapor, _CO2 , etc. by the ventilation part.

The packaging bag according to the present invention will be described in detail below with reference to examples and comparative examples. However, the packaging bag according to the present invention is not limited to the embodiments of the examples, and can be modified as appropriate without departing from the spirit of the present invention. The methods for evaluating the characteristics in the examples and comparative examples are as follows.

<Air release index>
A test specimen was cut into a rectangle of 60 mm x 60 mm so as to include the ventilation part, and the time until completion of degassing when degassing from a sealed space (small vacuum container) including the test specimen was measured using a Beck smoothness tester (HK type manufactured by Kumagai Riki Kogyo Co., Ltd.) specified in JIS P 8119 under conditions of a measured vacuum degree of 50.7 kPa to 48.0 kPa and a measured air volume of 1 cc based on 9.a in JIS P 8119. The average value (number of seconds) of five repeated measurements was taken as the air evacuation index (note that the test specimen was placed in the sealed space so that the ventilation part did not overlap with the degassing port and the measurement was performed).

<Automatic filling and packaging of fruits and vegetables>
Fruits and vegetables were automatically filled and packaged using a film roll laid out as shown in Fig. 1. That is, a synthetic resin film F was pulled horizontally from a film roll R, and the left and right edges were folded inward and pulled downward at a predetermined speed while overlapping the left and right edges and continuously heat-sealing (i.e., attaching the back) at a predetermined temperature (about 150°C), thereby continuously forming a tubular body T having a back seam B.

Simultaneously with the continuous formation of the tubular body T, a portion that will become the bottom seal portion _Sb of the packaging bag P was formed by heat sealing at a constant width in the width direction at a predetermined interval. Simultaneously with the formation of the bottom seal portion _Sb , a predetermined amount of fruit or vegetable was dropped from the upper funnel-shaped supply device I to fill the upper side of the bottom seal portion _Sb with the fruit or vegetable. Immediately after filling with the fruit or vegetable, a portion that will become the top seal portion S _t of the packaging bag P was formed by heat sealing at a constant width in the width direction at a predetermined interval. Simultaneously with the formation of the top seal portion S _t , a portion that will become the bottom seal portion _Sb (of the packaging bag P to be formed next) was formed by heat sealing at a constant width in the width direction at a predetermined interval.

Furthermore, simultaneously with the continuous formation of the tubular body T as described above, the steps of forming the bottom seal portion _Sb → filling with fruit and vegetables → forming the top seal portion S _t , and forming the bottom seal portion _Sb → filling with fruit and vegetables... were repeated to form a long tubular body T intermittently filled with the obtained fruit and vegetables. Then, the long tubular body T was cut between the top seal portion S _t and the bottom seal portion _Sb to continuously form packaging bags (hand-held bags) P containing the fruit and vegetables.

The automatic filling of fruits and vegetables using the film roll described above was carried out for four types of fruits and vegetables: shiitake mushrooms, broccoli, green soybeans, and mitsuba. For the automatic filling of shiitake mushrooms, a synthetic resin film with a width of 320 mm was used to create a packaging bag with a height (length in the longitudinal direction of the film) x width = 150 mm x 215 mm and containing 120 g of shiitake mushrooms. For the automatic filling of broccoli, a synthetic resin film with a width of 540 mm was used to create a packaging bag with a height x width = 260 mm x 360 mm and containing 270 g of broccoli. For the automatic filling of green soybeans, a synthetic resin film with a width of 300 mm was used to create a packaging bag with a height x width = 140 mm x 220 mm and containing 200 g of green soybeans. For the automatic filling of mitsuba, a synthetic resin film with a width of 200 mm was used to create a packaging bag with a height x width = 90 mm x 540 mm and containing 50 g of mitsuba.

<Ease of operation during automatic filling and packaging>
The workability when continuously forming packaging bags (double-sided bags) containing fruits and vegetables as described above was sensorily evaluated on the following three-level scale.
○: There was no unevenness in the end faces due to misalignment of the film roll, no blocking due to tightening, and automatic filling and packaging of fruits and vegetables was possible without any problems. △: There was unevenness in the end faces due to misalignment of the film roll, some blocking due to tightening, and some film meandering occurred during automatic filling and packaging of fruits and vegetables, hindering stable continuous production. ×: There was unevenness in the end faces due to misalignment of the film roll, and blocking due to tightening occurred, and film meandering frequently occurred during automatic filling and packaging of fruits and vegetables, making continuous production difficult.

<Freshness retention characteristics (shiitake mushrooms)>
The packaging bags (150 mm wide × 215 mm high, folded bags) containing shiitake mushrooms obtained in the Examples and Comparative Examples were stored in an atmosphere of 25°C × 65% RH for 72 hours (3 days). After that, the state of the packaged shiitake mushrooms was sensorily evaluated on the following 4-point scale in terms of dryness, color, and odor.
Evaluation criteria: ◎: No difference in color or odor was observed from before packaging. ○: Appears to be slightly dry, but no discoloration or strange odor was observed. △: Slight discoloration and a faint strange odor were observed. ×: Overall dryness, discoloration, obvious strange odor, mold growth, and decay were observed, and the product value was lost.

<Freshness retention characteristics (broccoli)>
The packaging bags (260 mm wide × 360 mm high, folded bags) containing broccoli obtained in the Examples and Comparative Examples were stored in an atmosphere of 25°C × 65% RH for 96 hours (4 days). After that, the condition of the packaged broccoli was sensorily evaluated on the following 4-point scale from the viewpoints of dryness, color, odor, and falling of flower buds.
Evaluation criteria: ◎: No difference in color or odor was observed from before packaging. ○: Appears to be slightly dry, but no discoloration or unpleasant odor was observed. △: Slight discoloration and a faint unpleasant odor were observed. ×: Overall dryness, discoloration, obvious unpleasant odor, mold growth, decay, or falling of flower buds were observed, and the product value was lost.

<Freshness retention characteristics (Edamame)>
The packaging bags containing soybeans obtained in the Examples and Comparative Examples (140 mm wide × 220 mm high, folded bags) were stored in an atmosphere of 25°C × 65% RH for 192 hours (8 days). After that, the state of the packaged soybeans was sensorily evaluated in terms of dryness, color, and odor using the following four-point scale.
Evaluation criteria: ◎: No difference in color or odor was observed from before packaging. ○: Appears to be slightly dry, but no discoloration or strange odor was observed. △: Slight discoloration and a faint strange odor were observed. ×: Overall dryness, discoloration, obvious strange odor, mold growth, and decay were observed, and the product value was lost.

<Freshness retention characteristics (Mitsuba)>
The packaging bags containing mitsuba obtained in the Examples and Comparative Examples (90 mm wide × 540 mm high, folded bags) were stored in an atmosphere of 20°C × 50% RH for 96 hours (4 days). After that, the state of the packaged soybeans was sensorily evaluated on the following 4-point scale in terms of dryness, color, and odor.
Evaluation criteria: ◎: No difference in color or odor was observed from before packaging. ○: Appears to be slightly dry, but no discoloration or strange odor was observed. △: Slight discoloration and a faint strange odor were observed. ×: Overall dryness, discoloration, obvious strange odor, mold growth, and decay were observed, and the product value was lost.

[Example 1]
Using a 20 μm thick long biaxially oriented polyolefin film (OPP film, P5562, manufactured by Toyobo Co., Ltd.) kneaded with an anti-fogging agent, three kinds of fruits and vegetables (shiitake mushroom, broccoli, and mitsuba) were automatically filled and packaged by the above-mentioned method to produce packaging bags (hand-held bags) containing fruits and vegetables. At that time, as shown in FIG. 2, a special gravure ink (PULPTECC Bell White D, manufactured by Tokyo Ink Co., Ltd.) mainly composed of nitrocellulose was coated on one end of the synthetic resin film F constituting the film roll R in a wide rectangular shape (longitudinal direction x width direction = 6 mm x 20 mm) at a predetermined interval (coated part C) to form a part that was not heat-sealed when forming the back seam (non-heat-sealed part). Therefore, a ventilation part consisting of a non-heat-sealed part was formed in the back seam of the packaging bag containing fruits and vegetables obtained by automatic filling and packaging. The workability when fruit and vegetables were automatically filled and packaged in this manner was evaluated by the above-mentioned method. In addition, the periphery of the ventilation part forming part of the synthetic resin film constituting the film roll forming the two-sided bag (i.e., a rectangular part of 60 mm x 60 mm including the part coated with the special gravure ink) was cut out, and the air release index of the cut out part was evaluated by the above-mentioned method.

FIG. 3 is a schematic diagram of the produced packaging bags containing fruits and vegetables (i.e., three types of packaging bags, i.e., packaging bags containing shiitake mushrooms, packaging bags containing broccoli, and packaging bags containing mitsuba). In the packaging bag _P1 , both the left and right sides of the synthetic resin film are folded inward, and the left and right ends are overlapped in the center and heat-sealed at a predetermined width to form a back seal B. In addition, the upper and lower ends are heat-sealed at a constant width to form an upper seal part S _t and a bottom seal part S _b , respectively. Then, non-heat-sealed parts (ventilation parts V ₁ ) are formed 30 mm below the upper seal part S _t and 30 mm above the bottom seal part S _b , respectively. In addition, the upper and lower edges of the packaging bag _P1 are cut into a saw-tooth shape. Using these packaging bags, the freshness-preserving effect was evaluated by the above-mentioned method. Table 1 shows the freshness-retaining properties of the three types of packaging bags (packaging bags P ₁ containing fruits and vegetables) and the ease of use during automatic filling and packaging of fruits and vegetables, together with the properties of the synthetic resin film (air escape index around the ventilation part).

[Example 2]
Using the same synthetic resin film as in Example 1, green soybeans, which are fruits and vegetables, were automatically filled and packaged in the same manner as in Example 1 to produce packaging bags (gassed bags) containing green soybeans. At that time, the vertical length (length along the longitudinal direction) of the non-heat-sealed portion (ventilation portion) formed on the back of the packaging bag (gassed bag) (heat-sealed portion at both ends of the synthetic resin film) was changed to 20 mm (i.e., a square-shaped special gravure ink coating portion measuring 20 mm x 20 mm in the longitudinal direction x width direction was formed at the edge of the synthetic resin film, forming two non-heat-sealed portions with a vertical width of 20 mm on the back). Otherwise, the packaging bag (gassed bag) containing green soybeans was produced in the same manner as in Example 1.

The workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the method described above. In addition, the periphery of the ventilation section of the synthetic resin film constituting the film roll forming the two-pronged bag (i.e., a rectangular section of 60 mm x 60 mm including the area coated with the special gravure ink) was cut out, and the air escape index of the cut-out section was evaluated by the method described above. Furthermore, the freshness-retention effect was evaluated by the method described above using the packaging bag containing edamame. The freshness-retention properties of the packaging bag (packaging bag containing fruits and vegetables) and the workability when the fruits and vegetables were automatically filled and packaged are shown in Table 1, along with the properties of the synthetic resin film (air escape index around the ventilation section).

[Example 3]
Using the same synthetic resin film as in Example 1, green soybeans and mitsuba were automatically filled and packaged in the same manner as in Example 1, and two types of packaging bags (hand-held bags) containing these fruits and vegetables were produced. At that time, as shown in Fig. 4, holes H of 6 mm diameter were formed at a predetermined interval on one end of the synthetic resin film F constituting the film roll R using a _CO2 laser marker to provide ventilation parts. Then, the workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the above-mentioned method. In addition, the synthetic resin film constituting the film roll forming the hand-held bags was cut out around the ventilation part (i.e., a rectangular part of 60 mm x 60 mm including the hole H of 6 mm diameter), and the air release index of the cut-out part was evaluated by the above-mentioned method.

FIG. 5 is a schematic diagram of the produced packaging bags containing fruits and vegetables (i.e., two types of packaging bags, one containing green soybeans and one containing mitsuba). The packaging bag _P3 has a back seam B, a top seal portion S _t , and a bottom seal portion S _b formed in the same manner as the packaging bag P1 of Example _1. A ventilation portion _V3 consisting of a hole with a diameter of 6 mm is formed in a portion adjacent to the back seam B in the center in the vertical direction (a portion 10 mm away from the base end of the back seam B). The freshness-preserving effect was evaluated by the above-mentioned method using these packaging bags _P3 . The freshness-preserving properties of the two types of packaging bags (packaging bags containing fruits and vegetables) and the workability during automatic filling and packaging of fruits and vegetables are shown in Table 1 together with the properties of the synthetic resin film (air escape index around the ventilation portion).

[Example 4-1]
Using the same synthetic resin film as in Example 1, automatic filling and packaging of shiitake mushrooms was carried out by the same method as in Example 1 to produce a packaging bag (a two-handed bag) containing shiitake mushrooms. At that time, a 0.5 mmφ hole was formed at a predetermined interval at one end of the synthetic resin film constituting the film roll, using a _CO2 laser marker, to provide a ventilation part. That is, a 0.5 mmφ hole functioning as a ventilation part was drilled in a part adjacent to the back lining (a part 10 mm away from the base end of the back lining) at the center in the height direction of the packaging bag containing fruits and vegetables. Then, the workability when the fruits and vegetables were automatically filled and packaged in this way was evaluated by the above-mentioned method. In addition, the synthetic resin film constituting the film roll forming the two-handed bag was cut out around the ventilation part (i.e., a rectangular part of 60 mm x 60 mm including the 0.5 mmφ hole), and the air release index of the cut-out part was evaluated by the above-mentioned method.

The packaging bag was then used to evaluate the freshness-retention effect using the method described above. The freshness-retention properties of the packaging bag (packaging bag containing fruit and vegetables) and the ease of use during automatic filling and packaging of fruit and vegetables are shown in Table 1, along with the properties of the synthetic resin film (air escape index around the ventilation part).

[Example 4-2]
Using the same synthetic resin film as in Example 1, automatic filling and packaging of broccoli and mitsuba was carried out in the same manner as in Example 1, and two types of packaging bags (hand-held bags) containing these fruits and vegetables were produced. At this time, ventilation parts were provided by continuously forming six holes of 0.5 mmφ at a predetermined interval on one end of the synthetic resin film constituting the film roll using a _CO2 laser marker. Then, the workability when carrying out automatic filling and packaging to produce packaging bags containing fruits and vegetables was evaluated by the above-mentioned method.

FIG. 6 is a schematic diagram of the produced packaging bags containing fruits and vegetables (i.e., two types of packaging bags, a packaging bag containing broccoli and a packaging bag containing mitsuba). The packaging bag _P4-2 has a back lining B, an upper seal portion S _t , and a bottom seal portion S _b formed in the same manner as the packaging bag P1 of Example _1. Six holes H, H... of 0.5 mm diameter that function as ventilation portions _V4-2 are drilled at intervals of 10 mm in a portion adjacent to the back lining B (a portion 10 mm away from the base end of the back lining B), and the upper three holes H, H... and the lower three holes H, H... are arranged symmetrically above and below with respect to the center in the height direction. The freshness-preserving effect was evaluated by the above-mentioned method using these packaging bags. The freshness-preserving properties of the two types of packaging bags (packaging bags containing fruits and vegetables) and the workability during automatic filling and packaging of fruits and vegetables are shown in Table 1 together with the properties of the synthetic resin film (air escape index around the ventilation portion).

[Example 5]
Using the same synthetic resin film as in Example 1, automatic filling and packaging of shiitake mushrooms, broccoli, and mitsuba was performed by the same method as in Example 1, and three types of packaging bags (hand-held bags) containing these fruits and vegetables were produced. At that time, ventilation parts were provided by forming slits (length x width = 5.0 mm x 0.18 mm) at a predetermined interval on one end of the synthetic resin film constituting the film roll using a roll equipped with a cutting blade (cutter). Then, the workability when automatically filling and packaging the packaging bags containing the fruits and vegetables was evaluated by the above-mentioned method. In addition, the synthetic resin film constituting the film roll forming the hand-held bags was cut out around the ventilation part (i.e., a rectangular part of 60 mm x 60 mm including the slit of length x width = 5.0 mm x 0.18 mm) and the air release index of the cut-out part was evaluated by the above-mentioned method.

FIG. 7 is a schematic diagram of the produced packaging bags containing fruits and vegetables (i.e., two types of packaging bags, a packaging bag containing green soybeans and a packaging bag containing mitsuba). The packaging bag _P5 has a back seal B, a top seal portion S _t , and a bottom seal portion S _b formed in the same manner as the packaging bag P1 of Example _1. A cut S (ventilation portion V5) having a length x width of 5.0 mm x 0.18 mm and functioning as a ventilation portion is formed in the center of the height direction adjacent to the back seal B (a portion 10 mm away from the base end of the back seal _B ). The freshness-preserving effect was evaluated by the above-mentioned method using these packaging bags. The freshness-preserving properties of the two types of packaging bags (packaging bags containing fruits and vegetables) and the workability during automatic filling and packaging of fruits and vegetables are shown in Table 1 together with the properties of the synthetic resin film (air escape index around the ventilation portion).

[Example 6-1]
Using the same synthetic resin film as in Example 1, automatic filling and packaging of shiitake mushrooms, broccoli, and mitsuba was performed by the same method as in Example 1, and three types of packaging bags (hand-held bags) containing these fruits and vegetables were produced. At that time, ventilation parts were provided by forming cuts (slits) of length x width = 5.0 mm x 0.05 mm at predetermined intervals on one end of the synthetic resin film constituting the film roll using a _CO2 laser marker. That is, a cut of length x width = 5.0 mm x 0.05 mm that functions as a ventilation part was formed in the center of the height direction of the packaging bag containing fruits and vegetables, adjacent to the back seam (10 mm away from the base end of the back seam). Then, the workability when automatically filling and packaging to produce packaging bags containing fruits and vegetables was evaluated by the above-mentioned method. In addition, the periphery of the ventilation portion forming portion of the synthetic resin film constituting the film roll forming the two-sided bag (i.e., a rectangular portion of 60 mm x 60 mm including a cut of length x width = 5.0 mm x 0.05 mm) was cut out, and the air release index of the cut out portion was evaluated by the above-mentioned method.

The three types of packaging bags obtained were then used to evaluate their freshness-retaining effects using the method described above. The freshness-retaining properties of the three types of packaging bags (packaging bags containing fruit and vegetables) and the ease of use when automatically filling and packaging fruit and vegetables are shown in Table 1, along with the properties of the synthetic resin film (air escape index around the ventilation part).

[Example 6-2]
Using the same synthetic resin film as in Example 1, automatic filling and packaging of green soybeans was carried out in the same manner as in Example 1 to produce packaging bags (hand-held bags) containing green soybeans. At this time, ventilation sections were provided by continuously forming three cuts (slits) of length x width = 5.0 mm x 0.05 mm at predetermined intervals on one end of the synthetic resin film constituting the film roll using a _CO2 laser marker. Then, the workability when carrying out automatic filling and packaging to produce packaging bags containing fruits and vegetables was evaluated by the above-mentioned method.

FIG. 8 is a schematic diagram of the packaging bag containing green soybeans that was produced. The packaging bag _P6-2 has a back seal B, an upper seal portion S _t , and a bottom seal portion S _b formed in the same manner as the packaging bag P1 of Example _1. Three slits S, S... each having a length x width of 5.0 mm x 0.05 mm and functioning as a ventilation portion _V6-2 are formed at 30 mm intervals in a portion adjacent to the back seal B in the center of the height direction (a portion 10 mm away from the base end of the back seal B), with the central slit S being disposed in the center of the height direction. The packaging bag was used to evaluate the freshness-preserving effect by the above-mentioned method. The freshness-preserving properties of the packaging bag (packaging bag containing fruits and vegetables) and the workability during automatic filling and packaging of fruits and vegetables are shown in Table 1 together with the properties of the synthetic resin film (air escape index around the ventilation portion).

[Example 7]
Using the same synthetic resin film as in Example 1, green soybeans and mitsuba were automatically filled and packaged in the same manner as in Example 1, and two types of packaging bags (gassed bags) containing these fruits and vegetables were produced. At that time, the diameter of the ventilation parts (circular holes) formed at predetermined intervals by a _CO2 laser marker on one end of the synthetic resin film constituting the film roll was changed to 8.0 mmφ, and the two types of packaging bags (gassed bags) containing fruits and vegetables were produced in the same manner as in Example 1. Then, the workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the above-mentioned method.

The synthetic resin film constituting the film roll forming the two-pronged bag was cut out around the ventilation area (i.e., a rectangular area of 60 mm x 60 mm including the 8.0 mm diameter hole), and the air release index of the cut-out area was evaluated using the method described above. Furthermore, the freshness-retention effect was evaluated using the method described above using these two types of packaging bags containing fruit and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruit and vegetables) and the operability during automatic filling and packaging of fruit and vegetables are shown in Table 1, along with the properties of the synthetic resin film (air release index around the ventilation area).

[Example 8-1]
Using the same synthetic resin film as in Example 1, automatic filling and packaging of shiitake mushrooms was carried out in the same manner as in Example 1 to produce packaging bags (gassed bags) containing the fruits and vegetables. At that time, except that the diameter of the ventilation parts (circular holes) formed at predetermined intervals at one end of the synthetic resin film constituting the film roll by a _CO2 laser marker was changed to 0.07 mmφ, packaging bags (gassed bags) containing the fruits and vegetables were produced in the same manner as in Example 1. Then, the workability when automatically filling and packaging the fruits and vegetables in this way was evaluated by the above-mentioned method.

The synthetic resin film constituting the film roll forming the two-pronged bag was cut out around the ventilation area (i.e., a rectangular area of 60 mm x 60 mm including a 0.07 mm diameter hole), and the air release index of the cut-out area was evaluated using the method described above. Furthermore, the freshness-retention effect was evaluated using the method described above using these two types of packaging bags containing fruit and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruit and vegetables) and the operability during automatic filling and packaging of fruit and vegetables are shown in Table 1, along with the properties of the synthetic resin film (air release index around the ventilation area).

[Example 8-2]
Using the same synthetic resin film as in Example 1, broccoli and mitsuba were automatically filled and packaged in the same manner as in Example 1, and two types of packaging bags (gabled bags) containing these fruits and vegetables were produced. At that time, 0.07 mmφ holes were continuously formed in two rows of four holes (total of eight holes) at a predetermined interval on one end of the synthetic resin film constituting the film roll using a _CO2 laser marker to provide ventilation parts. Then, other than that, two types of packaging bags (gabled bags) containing fruits and vegetables were produced in the same manner as in Example 1. Furthermore, the workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the above-mentioned method.

FIG. 9 is a schematic diagram of the produced packaging bags containing fruits and vegetables (i.e., two types of packaging bags, a packaging bag containing broccoli and a packaging bag containing mitsuba). The packaging bag _P8-2 has a back seam B, a top seal portion S _t , and a bottom seal portion S _b formed in the same manner as the packaging bag P1 of Example _1. Four holes H, H... each having a diameter of 0.07 mm, which function as the ventilation portion _V8-2 , are alternately drilled at intervals of 20 mm in a portion adjacent to the back seam B (a portion 10 mm away from the base end of the back seam B) and a portion adjacent to the outer edge (a portion 10 mm away from the outer edge). The center positions of the eight holes H, H... in the height direction are generally aligned with the center position of the entire packaging bag _P8-2 in the height direction. The freshness-preserving effect was evaluated by the above-mentioned method using these packaging bags. The freshness-retaining properties of the two types of packaging bags (packaging bags containing fruits and vegetables) and the ease of use during automatic filling and packaging of fruits and vegetables are shown in Table 1, along with the properties of the synthetic resin film (air escape index around the ventilation part).

[Comparative Example 1]
Using the same synthetic resin film as in Example 1, shiitake mushrooms, broccoli, green soybeans, and mitsuba were automatically filled and packaged in the same manner as in Example 1, and four types of packaging bags (gassed bags) containing these fruits and vegetables were produced. At that time, the vertical length (length along the longitudinal direction) of the non-heat-sealed part (ventilation part) formed on the back of the packaging bag (gassed bag) (heat-sealed part at both ends of the synthetic resin film) was changed to 45 mm (i.e., two non-heat-sealed parts with a vertical width of 20 mm were formed on the back by applying special gravure ink to the edge of the synthetic resin film in a rectangular shape of 45 mm x 20 mm in the longitudinal direction). Then, four types of packaging bags (gassed bags) containing fruits and vegetables were produced in the same manner as in Example 1 except for the above.

The workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated using the method described above. In addition, the periphery of the ventilation section of the synthetic resin film constituting the film roll forming the two-sided bag (i.e., a rectangular section of 60 mm x 60 mm including the area coated with the special gravure ink) was cut out, and the air escape index of the cut-out section was evaluated using the method described above. Furthermore, the freshness-retention effect was evaluated using the method described above using these four types of packaging bags containing fruits and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruits and vegetables) and the workability when the fruits and vegetables were automatically filled and packaged are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation section).

[Comparative Example 2]
Using the same synthetic resin film as in Example 1, shiitake mushrooms, broccoli, green soybeans, and mitsuba were automatically filled and packaged in the same manner as in Example 1, and four types of packaging bags (gassed bags) containing these fruits and vegetables were produced. At that time, the vertical length (length along the longitudinal direction) of the non-heat-sealed part (ventilation part) formed on the back of the packaging bag (gassed bag) (heat-sealed part at both ends of the synthetic resin film) was changed to 1.0 mm (i.e., two non-heat-sealed parts with a vertical width of 1.0 mm were formed on the back by applying special gravure ink to the edge of the synthetic resin film in a rectangular shape of longitudinal direction x width direction = 1.0 mm x 20 mm). Then, four types of packaging bags (gassed bags) containing fruits and vegetables were produced in the same manner as in Example 1 except for the above.

The workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated using the method described above. In addition, the periphery of the ventilation section of the synthetic resin film constituting the film roll forming the two-sided bag (i.e., a rectangular section of 60 mm x 60 mm including the area coated with the special gravure ink) was cut out, and the air escape index of the cut-out section was evaluated using the method described above. Furthermore, the freshness-retention effect was evaluated using the method described above using these four types of packaging bags containing fruits and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruits and vegetables) and the workability when the fruits and vegetables were automatically filled and packaged are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation section).

[Comparative Example 3-1]
Two types of packaging bags (gassed bags) containing fresh produce were produced by automatically filling and packaging shiitake mushrooms and edamame soybeans using the same synthetic resin film as in Example 1 and the same method as in Example 1. At that time, the diameter of the ventilation parts (circular holes) formed at predetermined intervals by a _CO2 laser marker on one end of the synthetic resin film constituting the film roll was changed to 10 mmφ, and the two types of packaging bags (gassed bags) containing fresh produce were produced in the same manner as in Example 3.

The workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the method described above. In addition, the periphery of the ventilation section of the synthetic resin film constituting the film roll forming the two-sided bag (i.e., a rectangular section of 60 mm x 60 mm including a 10 mm diameter hole) was cut out, and the air escape index of the cut-out section was evaluated by the method described above. Furthermore, the freshness-retention effect was evaluated by the method described above using these two types of packaging bags containing fruits and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruits and vegetables) and the workability when the fruits and vegetables were automatically filled and packaged are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation section).

[Comparative Example 3-2]
Broccoli and mitsuba were automatically filled and packaged by the same method as in Example 1 using the same synthetic resin film as in Example 1, and two types of packaging bags (gabled bags) containing these fruits and vegetables were produced. At that time, ventilation parts were provided by continuously forming six holes of 10 mm diameter at a predetermined interval using a _CO2 laser marker at one end of the synthetic resin film constituting the film roll. That is, six holes of 10 mm diameter functioning as ventilation parts were drilled at 30 mm intervals in a part adjacent to the back seam of the packaging bag containing fruits and vegetables (part 10 mm away from the base end of the back seam) so as to be symmetrical above and below the center in the height direction. Then, in the same manner as in Example 1 except for the above, two types of packaging bags (gabled bags) containing fruits and vegetables were produced.

The workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated using the method described above. Furthermore, the freshness-retention effect was evaluated using the method described above using these two types of packaging bags containing the fruits and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruits and vegetables) and the workability when automatically filling and packaging the fruits and vegetables are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation part).

[Comparative Example 5-1]
Three types of packaging bags (gassed bags) containing fresh produce were produced by automatically filling and packaging shiitake mushrooms, broccoli, and mitsuba using the same synthetic resin film as in Example 1 and the same method as in Example 1. The three types of packaging bags (gassed bags) containing fresh produce were produced in the same manner as in Example 5, except that the size of the ventilation parts (slits) formed at predetermined intervals by a cutting blade on one end of the synthetic resin film constituting the film roll was changed to length x width = 5.0 mm x 0.33 mm.

The workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the method described above. In addition, the periphery of the ventilation portion of the synthetic resin film constituting the film roll forming the two-sided bag (i.e., a rectangular portion of 60 mm x 60 mm including a cut of length x width = 5.0 mm x 0.33 mm) was cut out, and the air escape index of the cut out portion was evaluated by the method described above. Furthermore, the freshness retention effect was evaluated by the method described above using these three types of packaging bags containing fruits and vegetables. The freshness retention properties of the packaging bags (packaging bags containing fruits and vegetables) and the workability when automatically filling and packaging the fruits and vegetables are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation portion).

[Comparative Example 5-2]
Using the same synthetic resin film as in Example 1, green soybeans were automatically filled and packaged in the same manner as in Example 1 to produce a packaging bag (a two-handed bag) containing green soybeans. At that time, a roll equipped with a cutting blade (cutter) was used to continuously form three slits (slits) of length x width = 5.0 mm x 0.33 mm at a predetermined interval on one end of the synthetic resin film constituting the film roll, thereby providing a ventilation section. That is, three slits of length x width = 5.0 mm x 0.33 mm that function as ventilation sections were perforated at 30 mm intervals in a portion adjacent to the back seam of the packaging bag containing fresh produce (a portion 10 mm away from the base end of the back seam) so as to be symmetrical above and below the center in the height direction. Otherwise, a packaging bag (a two-handed bag) containing fresh produce was produced in the same manner as in Example 1.

The workability when fruit and vegetables were automatically filled and packaged in this manner was evaluated using the method described above. Furthermore, the freshness-retention effect was evaluated using the method described above using packaging bags containing fruit and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruit and vegetables) and the workability when fruit and vegetables were automatically filled and packaged are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation part).

[Comparative Example 6-1]
Three types of packaging bags (gassed bags) containing fresh produce were produced by automatically filling and packaging shiitake mushrooms, broccoli, and mitsuba using the same synthetic resin film as in Example 1 and the same method as in Example 1. At that time, the size of the ventilation parts (slits) formed at predetermined intervals by a _CO2 laser marker on one end of the synthetic resin film constituting the film roll was changed to length x width = 5.0 mm x 0.005 mm, and the three types of packaging bags (gassed bags) containing fresh produce were produced in the same manner as in Example 6-1.

The workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the method described above. In addition, the periphery of the ventilation portion of the synthetic resin film constituting the film roll forming the two-sided bag (i.e., a rectangular portion of 60 mm x 60 mm including a cut of length x width = 5.0 mm x 0.005 mm) was cut out, and the air escape index of the cut out portion was evaluated by the method described above. Furthermore, the freshness retention effect was evaluated by the method described above using these three types of packaging bags containing fruits and vegetables. The freshness retention properties of the packaging bags (packaging bags containing fruits and vegetables) and the workability when automatically filling and packaging the fruits and vegetables are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation portion).

[Comparative Example 6-2]
Green soybeans were automatically filled and packaged in a packaging bag (gassed bag) containing green soybeans by the same method as in Example 1 using the same synthetic resin film as in Example 1. At that time, the size of each of the three ventilation parts (slits) formed at predetermined intervals on one end of the synthetic resin film constituting the film roll by a _CO2 laser marker was changed to length x width = 5.0 mm x 0.005 mm, and the packaging bag (gassed bag) containing fruits and vegetables was produced in the same manner as in Example 6-2.

The workability when fruit and vegetables were automatically filled and packaged in this manner was evaluated using the method described above. Furthermore, the freshness-retention effect was evaluated using the method described above using packaging bags containing fruit and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruit and vegetables) and the workability when fruit and vegetables were automatically filled and packaged are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation part).

[Comparative Example 7-1]
Using the same synthetic resin film as in Example 1, automatic filling and packaging of shiitake mushrooms and edamame beans was performed by the same method as in Example 1, and two types of packaging bags (gassed bags) containing these fruits and vegetables were produced. At that time, ventilation parts were provided by forming holes H of 10 mmφ at predetermined intervals at one end of the synthetic resin film constituting the film roll using a hot needle heated to about 140°C. That is, a hole H of 10 mmφ functioning as a ventilation part was drilled in the center of the height direction in a part adjacent to the back seam of the packaging bag containing fruits and vegetables (a part 10 mm away from the base end of the back seam) (see FIG. 5). Then, two types of packaging bags (gassed bags) containing fruits and vegetables were produced in the same manner as in Example 1 except for the above.

The workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the method described above. In addition, the periphery of the ventilation section of the synthetic resin film constituting the film roll forming the two-sided bag (i.e., a rectangular section of 60 mm x 60 mm including a 10 mm diameter hole) was cut out, and the air escape index of the cut-out section was evaluated by the method described above. Furthermore, the freshness-retention effect was evaluated by the method described above using these two types of packaging bags containing fruits and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruits and vegetables) and the workability when the fruits and vegetables were automatically filled and packaged are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation section).

[Comparative Example 7-2]
Broccoli and mitsuba were automatically filled and packaged by the same method as in Example 1 using the same synthetic resin film as in Example 1, and two types of packaging bags (hand-held bags) containing the fruits and vegetables were produced. At that time, 10 mmφ holes were continuously formed in two rows of four holes (total of eight holes) at a predetermined interval on one end of the synthetic resin film constituting the film roll using two hot needles heated to about 140°C, to provide ventilation parts. That is, four holes H, H... each of which has a diameter of 10 mm and functions as ventilation parts were alternately formed at 20 mm intervals in the part adjacent to the back seam (part 10 mm away from the base end of the back seam) and the part adjacent to the outer edge (part 10 mm away from the outer edge) of the packaging bag containing the fruits and vegetables (see FIG. 9). Then, two types of packaging bags (hand-held bags) containing the fruits and vegetables were produced in the same manner as in Example 1 except for the above.

The workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the method described above. In addition, the periphery of the ventilation section of the synthetic resin film constituting the film roll forming the two-sided bag (i.e., a rectangular section of 60 mm x 60 mm including a 10 mm diameter hole) was cut out, and the air escape index of the cut-out section was evaluated by the method described above. Furthermore, the freshness-retention effect was evaluated by the method described above using these two types of packaging bags containing fruits and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruits and vegetables) and the workability when the fruits and vegetables were automatically filled and packaged are shown in Table 2, along with the properties of the synthetic resin film (air escape index around the ventilation section).

[Comparative Example 8-1]
Using the same synthetic resin film as in Example 1, automatic filling and packaging of shiitake mushrooms and edamame beans was carried out in the same manner as in Example 1, and two types of packaging bags (gassed bags) containing these fruits and vegetables were produced. At that time, ventilation sections were provided by forming holes H of 0.03 mmφ at predetermined intervals using a _CO2 laser marker on one end of the synthetic resin film F constituting the film roll R. Then, other than that, two types of packaging bags (gassed bags) containing fruits and vegetables were produced in the same manner as in Example 1. Furthermore, the workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the above-mentioned method.

The synthetic resin film constituting the film roll forming the two-pronged bag was cut out around the ventilation area (i.e., a rectangular area of 60 mm x 60 mm including a 0.03 mm diameter hole), and the air release index of the cut-out area was evaluated using the method described above. Furthermore, the freshness-retention effect was evaluated using the method described above using these two types of packaging bags containing fruit and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruit and vegetables) and the operability during automatic filling and packaging of fruit and vegetables are shown in Table 2, along with the properties of the synthetic resin film (air release index around the ventilation area).

[Comparative Example 8-2]
Broccoli and mitsuba were automatically filled and packaged in the same manner as in Example 1 using the same synthetic resin film as in Example 1, and two types of packaging bags (gabled bags) containing these fruits and vegetables were produced. At that time, the diameter of the ventilation parts (eight circular holes) formed at a predetermined interval on one end of the synthetic resin film constituting the film roll by a _CO2 laser marker was changed to 0.03 mmφ, and the two types of packaging bags (gabled bags) containing fruits and vegetables were produced in the same manner as in Example 8-2. Then, the workability when the fruits and vegetables were automatically filled and packaged in this manner was evaluated by the above-mentioned method.

The synthetic resin film constituting the film roll forming the two-pronged bag was cut out around the ventilation area (i.e., a rectangular area of 60 mm x 60 mm including a 0.03 mm diameter hole), and the air release index of the cut-out area was evaluated using the method described above. Furthermore, the freshness-retention effect was evaluated using the method described above using these two types of packaging bags containing fruit and vegetables. The freshness-retention properties of the packaging bags (packaging bags containing fruit and vegetables) and the operability during automatic filling and packaging of fruit and vegetables are shown in Table 2, along with the properties of the synthetic resin film (air release index around the ventilation area).

From Table 1, it can be seen that when fruit and vegetables are automatically packed and packaged with a film roll whose air release index around the ventilation section meets the requirements of the present invention (Examples 1 to 8), the fruit and vegetables can be automatically packed and packaged efficiently and smoothly without uneven edges due to misalignment of the winding or blocking due to tight winding. It can also be seen that the packaging bags containing fruit and vegetables in Examples 1 to 8 that are automatically packed and packaged with a film roll whose air release index around the ventilation section meets the requirements of the present invention have a good freshness-preserving effect.

In contrast, Table 2 shows that when fruit and vegetables are automatically packed with a film roll whose air release index around the ventilation area does not meet the requirements of the present invention (Comparative Examples 1-3, 5-8), the fruit and vegetables cannot be automatically packed smoothly due to the occurrence of unevenness of the end faces due to misalignment of the winding and blocking due to tight winding. It is also clear that the packaging bags containing fruit and vegetables in Comparative Examples 1-3, 5-8, which are automatically packed with a film roll whose air release index around the ventilation area does not meet the requirements of the present invention, have poor freshness-preserving properties.

The film roll according to the present invention has the excellent effects described above, and therefore can be suitably used as a component for automatic filling and packaging of fruits and vegetables such as edamame and broccoli. In addition, the packaging bag according to the present invention has the excellent effects described above, and therefore can be suitably used as a packaging bag for preserving the freshness of fruits and vegetables.

F: Synthetic resin film R: Film roll P ₁ , P ₃ , P _4-2 , P ₅ , P _6-2 , P _8-2 : Packaging bag V ₁ , V ₃ , V _4-2 , V ₅ , V _6-2 , V _8-2 : Ventilation section

Claims (4)

A film roll made by winding a long synthetic resin film used in automatic filling and packaging of fruits and vegetables, which automatically fills the fruits and vegetables and forms freshness-preserving packaging bags at the same time,
A ventilation section for promoting air circulation between the front and back sides is formed by drilling one or more holes at a predetermined interval in the synthetic resin film,
The air evacuation index of the synthetic resin film at the center of the ventilation portion is 3,000 seconds or more and 55,000 seconds or less, and
The freshness-preserving packaging bag is a two-sided bag formed by folding the left and right sides of the synthetic resin film, joining the left and right ends at the center, and heat-sealing the left and right ends at a predetermined width to form a back seam,
A film roll for packaging fruits and vegetables, characterized in that the ventilation section is formed at a position adjacent to the spine at the vertical center of the formed two-sided bag . The film roll for packaging fruits and vegetables according to claim 1, characterized in that the holes serving as the ventilation sections are 0.05 mm or more and less than 8.0 mm in diameter. The film roll for packaging fruits and vegetables according to claim 1 or 2, characterized in that an anti-fogging agent is present on the surface of the synthetic resin film that will become the inside of the freshness-preserving packaging bag after automatic filling. A freshness-preserving bag for fruits and vegetables, formed by automatic filling and packaging of fruits and vegetables using the film roll for packaging fruits and vegetables according to any one of claims 1 to 3.

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