JP7314764B2 - pouch - Google Patents

Description

The present invention relates to a pouch obtained by heat-sealing a laminated film.

For example, pouches for microwave ovens containing retort foods and frozen foods are widely used. When the pouch is heated in a microwave oven, the moisture contained in the contents evaporates with the heating, and the pressure inside the pouch rises. If the pressure inside the pouch increases, the pouch may break and the contents may scatter.

Therefore, there has been proposed a pouch provided with a vapor release mechanism for releasing the vapor generated by heating to the outside of the bag.
Patent Literature 1 discloses a self-supporting packaging bag in which a notch is provided in an upper side seal portion and an easily peelable material is used in a heat-sealed portion around the notch. In the self-supporting packaging bag of Patent Document 1, when the pressure inside the pouch increases due to heating, the heat-sealed portion using an easily peelable material is peeled off, and the storage space inside the pouch communicates with the outside of the pouch, allowing the steam inside the pouch to escape to the outside through the notch.

Patent Documents 2 to 4 disclose a sealed area formed by heat-sealing a laminated film in a peripheral area surrounding an accommodation space, an unsealed area that is isolated from the accommodation space by the sealed area and is not heat-sealed, and a pouch having a shape in which the sealed area protrudes toward the accommodation space where the unsealed area is formed. In the pouches of Patent Documents 2 to 4, two laminated films are superimposed and heat-sealed in the vicinity of the periphery of the laminated film to produce the pouch. When the pressure inside the pouch increases due to heating, stress is concentrated at the corners of the overhanging portion. As a result, the seal area of the protruding portion is peeled off, so that the storage space and the unsealed area are communicated with each other, allowing the steam in the pouch to escape to the outside.

Japanese Unexamined Patent Application Publication No. 2010-36968 JP 2015-120550 A JP 2016-74457 A JP 2016-74458 A

In the packaging bag of Patent Document 1, it was necessary to form only the heat-sealed portion around the notch with an easily peelable material. There is a problem that the manufacturing process is complicated, the cost is increased, and the material cost is also high. In addition, when using an easily peelable material, sufficient sealing strength cannot be secured, and when the pouch is subjected to impact such as when dropped, peeling may occur at the heat-sealed portion around the notch, and the contents may leak.

In Patent Documents 2 to 4, the sealant must be a material that softens when heated in a microwave oven and the sealing strength decreases. For this reason, sealant materials are limited. In addition, the formation of the protruding portion makes it easy for the steam to escape, but the steam may escape slowly, and in this case, the seal may retreat at the sealing portion other than the protruding portion.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a pouch that can suppress the occurrence of seal retraction when the internal pressure increases due to heating, can release steam to the outside from a desired location, and can effectively suppress the ejection of the contents to the outside during heating.

In order to solve the above problems, the present invention provides the following [1] to [7].
[1] A pouch made by stacking and heat-sealing at least one laminated film having a sealant layer so that the sealant layer is on the inner layer side, and having a storage space for containing a content, the pouch having a side seal portion formed by heat-sealing the laminated film, wherein the side seal portion is connected to a side edge seal portion located on the side edge side of the laminate film and to the side edge seal portion on the side opposite to the side edge of the laminate film, and closer to the storage space side than the side edge seal portion. a projecting seal portion having a pair of projecting portions projecting toward the pouch, wherein the projecting portions are arranged in the direction in which the side edges extend, and at least one of the laminated films has a heat-generating ink layer in an outer layer than the sealant layer, and the heat-generating ink layer is provided at least in a region between the tips of the pair of projecting portions, including the side end seal portion.
[2] The pouch according to [1], wherein the exothermic ink layer is provided so as to reach the inner edge of the side seal portion on the housing space side.
[3] The pouch according to [1] or [2], wherein the exothermic ink layer is provided in a part of the storage space beyond the inner edge of the side seal portion on the storage space side.
[4] The pouch according to any one of [1] to [3], wherein the exothermic ink layer is provided so as to reach the edge of the side seal portion on the opposite side of the housing space.
[5] The pair of protrusions are spaced apart from each other, the inner edge of the side end seal portion between the pair of protrusions faces the storage space, and the exothermic ink layer is not provided on the pair of protrusions. The pouch according to any one of [1] to [4].
[6] The pair of protrusions are separated from each other, the inner edge of the side end seal portion between the pair of protrusions faces the storage space, and the exothermic ink layer includes a part of the pair of protrusions, and is formed so that it is not provided at the tip of the pair of protrusions, the pouch according to any one of [1] to [4].
[7] The pouch according to any one of [1] to [4], wherein the width in the first direction of the region where the heat-generating ink layer is provided is provided in a region having a ratio of 0.1 to 0.8 of the width in the first direction of the overhang seal portion, and is not provided at each of the tip portions of the protrusions, when the pair of protrusions are in contact with each other and the direction in which the pair of protrusions are arranged is defined as the first direction.

ADVANTAGE OF THE INVENTION According to this invention, the pouch which can suppress generation|occurrence|production of seal|sticker recession|retreat, and can discharge|release vapor|steam outside from a desired location when internal pressure rises by heating can be obtained. Furthermore, according to the present invention, it is possible to obtain a pouch that can effectively suppress the ejection of the contents to the outside during heating.

1 is a plan view showing a pouch of one embodiment of the present invention; FIG. It is a cross-sectional schematic diagram which shows the layer structure of a laminated|multilayer film. FIG. 4 is an enlarged view of the first side seal portion near the overhang seal portion in the pouch according to the first embodiment; It is a modification of the pouch which concerns on 1st Embodiment, and is an enlarged view of the 1st side seal|sticker part near an overhang seal|sticker part. FIG. 11 is an enlarged view of the first side seal portion near the overhang seal portion in the pouch according to the second embodiment; It is a modified example of the pouch according to the second embodiment, and is an enlarged view of the first side seal portion near the overhang seal portion. FIG. 11 is an enlarged view of the first side seal portion near the overhang seal portion in the pouch according to the third embodiment; FIG. 12 is an enlarged view of the first side seal portion near the overhang seal portion in the pouch according to the fourth embodiment; FIG. 12 is an enlarged view of the first side seal portion near the overhang seal portion in the pouch according to the fifth embodiment; It is a modified example of the pouch according to the fifth embodiment, and is an enlarged view of the first side seal portion near the overhang seal portion.

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. Note that the notation of a numerical range of "AA to BB" in this specification means "from AA to BB".

The present invention is a pouch made by stacking and heat-sealing at least one laminated film having a sealant layer so that the sealant layer is on the inner layer side, and having a storage space for containing a content, the pouch having a side seal portion formed by heat-sealing the laminated film, the side seal portion being connected to the side edge seal portion located on the side edge side of the laminate film and the side edge seal portion on the side opposite to the side edge of the laminate film, and closer to the storage space than the side edge seal portion. and a projecting seal portion having a pair of projecting portions projecting toward the pouch, wherein the projecting portions are arranged in the direction in which the side edges extend, and at least one of the laminated films has a heat-generating ink layer in an outer layer than the sealant layer, and the heat-generating ink layer is provided at least in a region between the tips of the pair of projecting portions, including the side end seal portion.

[Pouch]
FIG. 1 shows a plan view of a pouch according to one embodiment of the present invention. The pouch shown in FIG. 1 is a flat bag type pouch. The pouch 1 is composed of two sheets 11 (a front sheet 11a and a back sheet 11b) which are placed one on top of the other, and the vicinity of side edges 13 and bottom edges 14 of the sheets 11 are heat-sealed to each other. Thereby, a storage space 2 for storing contents is formed between the two sheets 11 .

As shown in FIG. 1, the pouch 1 has an opening 4 formed between the upper edges 12 of the sheet 11 . The pouch 1 is devised to ensure a wide opening 4 so that the contents can be efficiently filled into the storage space 2 through the opening 4. - 特許庁After the contents are filled, the vicinity of the upper edge 12 provided with the opening 4 is heat-sealed to obtain the pouch 1 .

In addition, the present invention can be similarly applied to pouches of other shapes such as standing pouches, gusseted pouches, box pouches, four-sided pouches, three-sided pouches, and the like.

[Laminated film]
In this embodiment, at least one of the two sheets 11 is made of the laminated film 30 .
FIG. 2 is a schematic cross-sectional view showing the layer structure of the laminated film 30. As shown in FIG. The pouch of this embodiment is manufactured by heat-sealing two sheets of laminated film 30 . The laminate film 30 is provided with a sealant layer 34 having a sealing property on a portion that will be the inner side of the container. In addition, the laminated film 30 is provided with a base layer 31 that serves as a base for printing in a portion that is closer to the outside of the container than the sealant layer 34 . A heat-generating ink layer 36 is provided between the substrate layer 31 and the sealant layer 34 in the laminated film 30 . Furthermore, the laminate film 30 includes an intermediate base layer 33 between the base layer 31 and the sealant layer 34 in order to provide various functions required for microwave pouches.

When one of the sheets 11 is made of the laminated film 30, the other sheet is preferably made of a film having the same configuration as the laminated film 30 illustrated in FIG. 2 except that the heat-generating ink layer is not provided.

The pouch 1 of the present embodiment is described as an example in which two sheets 11 are stacked to form a bag, but a single sheet (laminated film 30) may be folded so that the sealant layer 34 is on the inner side of the container.

Depending on the type of pouch, the number of laminate films used can be appropriately changed. For example, in the case of a standing pouch, it is preferable to use three laminated films of a front sheet, a back sheet and a bottom sheet. In this case, the bottom sheet is preferably made of a film having the same configuration as the laminated film 30 illustrated in FIG. 2 except that the heat-generating ink layer is not provided.

Each layer will be described in detail below.
[Base material layer]
The base layer 31 is the outermost layer of the laminated film 30 when the pouch 1 is formed by bag-making.
It is preferable that the base layer 31 has transparency so that the pattern layer 32 (described later) laminated on the inner surface of the base layer 31 can be visually recognized through the base layer 31 when the pouch 1 is formed by bag making.
Moreover, the pouch 1 for microwave ovens is required to have resistance to heat. Therefore, the base material layer 31 of this embodiment is made of a heat-resistant material. For example, as the base layer 31, a stretched polyethylene terephthalate film, a stretched nylon film, a stretched polypropylene film, a polypropylene/ethylene-vinyl alcohol copolymer coextruded costretched film, or a composite film in which two or more of these films are laminated can be used.
As the above-mentioned film, in order to enhance the gas barrier property, a film obtained by vapor deposition of an inorganic substance such as silicon oxide or aluminum oxide, or a film formed with a coating film of ethylene-vinyl alcohol copolymer may be used.

The thickness of the base material layer 31 is preferably 10 to 50 μm, for example. Within this thickness range, the product cost can be suppressed while satisfying the heat resistance required for the pouch 1 .

[Heat-generating ink layer]
In this embodiment, the heat-generating ink layer 36 is laminated on the surface of the base material layer 31 facing the accommodation space. The heat-generating ink layer 36 is provided between the base material layer 31 and the sealant layer 34 . That is, the heat-generating ink layer is a layer outside the sealant layer 34 . The heat-generating ink layer 36 is formed at a predetermined position within the plane of the substrate layer 31 so as to be provided at a predetermined position when the pouch 1 is formed as described later.
The thickness of the heat-generating ink layer is preferably 0.1 μm or more, more preferably 0.5 μm or more, in consideration of the amount of heat generated when heated in a microwave oven, coatability, manufacturing cost, and the like. In addition, from the viewpoint of preventing damage to the laminated film due to heat generated during microwave heating, the thickness of the heat-generating ink layer is preferably 5 μm or less, more preferably 4 μm or less, and particularly preferably 3 μm or less.

The exothermic ink layer 36 contains a material that absorbs microwaves. Materials that absorb microwaves include one or more selected from conductive polymers and conductive particles. Among these, conductive polymers are preferable because they have good visible light transmittance and are less likely to generate sparks due to microwaves.
The conductive polymer is preferably one or more compounds selected from polythiophenes, polypyrroles, polyanilines, polyacetylenes, polyphenylenes, polyphenylene vinylenes, polyacenes and polythiophene vinylenes, and more preferably contains a dopant in addition to these compounds.
Dopants include halogens, Lewis acids, protonic acids, organic carboxylic acids, transition metal halides, electrolyte anions, organic cyano compounds, quinones, alkali metals, alkaline earth metals, amino acids, nucleic acids, surfactants, dyes, alkylammonium ions and quaternary phosphonium salts.
Conductive particles include carbon black and metal particles.

When conductive particles are used, the heat-generating ink layer preferably contains a binder resin. Also, when a conductive polymer is used, other resins may be contained for adjusting the conductivity. The resin is not particularly limited as long as it is a material that does not inhibit the heat build-up. Examples of resins include polyolefin resins such as polyethylene resins and chlorinated polypropylene resins, poly(meth)acrylic resins, polyvinyl chloride resins, polyvinyl acetate resins, vinyl chloride-vinyl acetate copolymers, polystyrene resins, styrene-butadiene copolymers, vinylidene fluoride resins, polyvinyl alcohol resins, polyvinyl acetal resins, polyvinyl butyral resins, polybutadiene resins, polyester resins, polyamide resins, alkyd resins, epoxy resins, Examples include saturated polyester resins, thermosetting poly(meth)acrylic resins, melamine resins, urea resins, polyurethane resins, phenolic resins, xylene resins, maleic acid resins, cellulose resins such as nitrocellulose, ethyl cellulose, acetylbutyl cellulose, and ethyloxyethyl cellulose, rubber resins such as chlorinated rubber and cyclized rubber, petroleum resins, rosin, and natural resins such as casein.

The heat-generating ink for forming the heat-generating ink layer may further contain optional additives such as pigments, fillers, stabilizers, plasticizers, antioxidants, light stabilizers such as ultraviolet absorbers, dispersants, thickeners, desiccants, lubricants, and cross-linking agents, as long as they do not impair the heat-generating properties.

As the solvent contained in the exothermic ink, solvents used in ordinary pigment inks can be applied. For example, alcohol solvents such as methanol, ethanol, normal propanol, isopropanol, propylene glycol monomethyl ether, etc.; Examples include alicyclic hydrocarbon solvents such as butane, aromatic solvents such as toluene and xylene, and mineral spirits. These may be used individually by 1 type, or may use 2 or more types together.

The heat-generating ink layer 36 can be formed by a known printing method such as gravure printing, offset printing, letterpress printing, and silk screen printing using the above-described heat-generating ink.

If the adhesion between the heat-generating ink layer 36 and the base material layer 31 is not good, an anchor coat layer may be provided between the heat-generating ink layer 36 and the base material 31 .

[Sealant layer]
As described above, the sealant layer 34 is provided for bonding and sealing the edges by overlapping the two laminated films 30 and heat-sealing the vicinity of the opposing edges. Moreover, the sealant layer 34 is a layer positioned closest to the accommodation space side (inner side) of the laminated film 30 when the pouch 1 is formed by bag-making.
In addition to heat sealability, the sealant layer 34 is required to have heat resistance when heated in a microwave oven, impact resistance during transportation and dropping, and the like.

As the sealant layer 34, films containing polyolefin resins such as polyethylene, polypropylene, ethylene-vinyl acetate copolymer, ethylene-propylene random copolymer, and ethylene-propylene block copolymer can be used. Specifically, it is preferable to use low-density polyethylene (LDPE) such as unstretched polypropylene (CPP) and linear low-density polyethylene (LLDPE) as the sealant layer 34 . By using low-density polyethylene (LDPE), impact resistance during transportation can be enhanced. Moreover, the sealant layer 34 may further contain an olefinic elastomer from the viewpoint of impact resistance and puncture resistance.
The sealant layer 34 may be composed of a single layer, or may be composed of a multi-layered structure consisting of a plurality of layers. The material and layer structure of each layer can be appropriately changed according to required specifications such as impact resistance, heat sealability, and easy peelability.

The thickness of the sealant layer 34 is preferably in the range of 40 μm to 200 μm.
In this case, the pouch 1 is excellent in impact resistance against dropping that may occur during the distribution process, and is also excellent in handleability such as ease of filling and taking out of the contents.

[Pattern layer]
In this embodiment, a pattern layer 32 including a pattern is laminated on the surface of the base material layer 31 which is the inner side of the container. That is, the pattern layer 32 is provided between the base material layer 31 and the sealant layer 34 .
As shown in FIG. 2, the pattern layer 32 is preferably provided closer to the sealant layer 34 than the heat-generating ink layer 36 from the viewpoint of ensuring safety during handling by making the heat-generating ink layer visible. Alternatively, considering the visibility of the pattern layer and the efficiency of transferring the heat generated in the heat-generating ink layer to the sealant layer, a pattern layer may be formed on the base material layer, and the heat-generating ink layer may be provided on the pattern layer.
Further, as a modification of FIG. 2, a configuration in which the heat-generating ink layer and the pattern layer are not laminated may be employed. In this case, when the laminated film is viewed in plan, the heat-generating ink layer and the pattern layer may be adjacent to each other, or the heat-generating ink layer and the pattern layer may be separated from each other.

A pattern is a recording object of various aspects that can be recorded or printed on the base material layer 31, and includes a wide range of drawings, characters, designs, patterns, symbols, designs, marks, etc., without being particularly limited. In the laminated film 30 used in the pouch 1 intended to enclose food, a picture of the contents and letters indicating information such as the product name of the contents, the expiration date, the date of manufacture, and the manufacture number are used as the pattern.
The pattern layer 32 may be formed on the entire surface of the base material layer 31 or may be formed partially. The design layer 32 is laminated on the base material layer 31 according to product specifications, and the design layer 32 may not be provided on the base material layer 31 .

In this embodiment, the pattern layer 32 is formed on the inner surface of the base material layer 31 . With such a configuration, the pattern layer 32 is excellent in abrasion resistance, so that it can effectively prevent disappearance due to rubbing or the like, and can also effectively prevent falsification of the pattern.

The pattern layer mainly contains a colorant and a binder resin.
Colorants include white pigments such as titanium dioxide, barium sulfate, magnesium oxide, calcium carbonate, zinc oxide and lead white; black pigments such as carbon black, titanium black and iron black; chromatic inorganic pigments such as yellow lead, titanium yellow, iron oxide, cadmium red, ultramarine blue and cobalt blue; chromatic organic pigments such as quinacridone red, isoindolinone yellow and phthalocyanine blue; Two or more kinds can be used.

The pattern layer can be formed, for example, on the substrate layer by a known printing method such as gravure printing, offset printing, letterpress printing, or silk screen printing, using known ink. The pattern layer forming ink usually contains a vehicle comprising a binder resin and a solvent as a main component.

Examples of binder resins include polyolefin resins such as polyethylene resins and chlorinated polypropylene resins, poly(meth)acrylic resins, polyvinyl chloride resins, polyvinyl acetate resins, vinyl chloride-vinyl acetate copolymers, polystyrene resins, styrene-butadiene copolymers, vinylidene fluoride resins, polyvinyl alcohol resins, polyvinyl acetal resins, polyvinyl butyral resins, polybutadiene resins, polyester resins, polyamide resins, alkyd resins, epoxy resins, Examples include unsaturated polyester resins, thermosetting poly(meth)acrylic resins, melamine resins, urea resins, polyurethane resins, phenolic resins, xylene resins, maleic acid resins, cellulose resins such as nitrocellulose, ethyl cellulose, acetylbutyl cellulose, and ethyloxyethyl cellulose, rubber resins such as chlorinated rubber and cyclized rubber, petroleum resins, rosin, and natural resins such as casein.

The picture layer-forming ink may further contain optional additives such as fillers, stabilizers, plasticizers, antioxidants, light stabilizers such as UV absorbers, dispersants, thickeners, desiccants, lubricants, antistatic agents, and cross-linking agents, if necessary.

As the solvent contained in the ink of the pattern layer, solvents used in ordinary pigment inks can be applied. For example, alcohol solvents such as methanol, ethanol, normal propanol, isopropanol, and propylene glycol monomethyl ether; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; ester solvents such as methyl acetate, ethyl acetate, and normal propyl acetate; , alicyclic hydrocarbon solvents such as cycloheptane, aromatic solvents such as toluene and xylene, and mineral spirits. These may be used individually by 1 type, or may use 2 or more types together.

The content of the coloring agent in the pattern layer is not particularly limited, but is preferably 5 to 70% by mass, more preferably 15 to 65% by mass, and even more preferably 20 to 60% by mass of the total solid content of the pattern layer.

The thickness of the pattern layer is not particularly limited, and is preferably about 1.0 to 5.0 μm, more preferably 1.0 to 3.0 μm.

[Other layers]
The laminated film 30 of the present invention may have an intermediate substrate layer 33 between the substrate layer 31 and the sealant layer 34 . The intermediate base material layer 33 is provided to supplement various functions required of the microwave pouch.
Specifically, in order to make a pouch suitable for enclosing food as a content, the intermediate base material layer 33 may have a gas barrier property that prevents permeation of gases such as water vapor and oxygen gas so that the content can be preserved while preventing deterioration such as oxidation of the content. Also, the standing pouch type pouch 1 is displayed in a self-supporting state on a product shelf in a sales floor. For this reason, the intermediate base material layer 33 may have bending resistance and impact resistance so that it can sufficiently withstand the impact when the pouch 1 falls from the product shelf. Further, the intermediate base material layer 33 may have a function of sufficiently enhancing the concealability so that the contents of the pouch 1 cannot be seen, in order to increase consumer willingness to buy.

As the intermediate base material layer 33 having such a function, for example, films such as polyolefins such as polyethylene terephthalate, polyamide, polyethylene, and polypropylene, nylon, polyvinyl chloride, polycarbonate, polyvinyl alcohol, ethylene-propylene copolymers, ethylene-vinyl acetate copolymer saponified products can be used. As the above-mentioned film, a film on which an inorganic substance such as silicon oxide or aluminum oxide is vapor-deposited, or a film on which a coating film of ethylene-vinyl alcohol copolymer is formed may be used.
The intermediate base material layer 33 may be composed of one of the films listed above, or may be used in combination of two or more.

As shown in FIG. 2 , in this embodiment, a bonding layer 35 is interposed between the base layer 31 and the intermediate base layer 33 and between the intermediate base layer 33 and the sealant layer 34 . As the bonding layer 35, an adhesive generally used in a known dry lamination method can be used. For example, polyvinyl acetate-based adhesives, polyacrylate-based adhesives, cyanoacrylate-based adhesives, ethylene copolymer-based adhesives, cellulose-based adhesives, polyester-based adhesives, polyamide-based adhesives, amino resin-based adhesives, epoxy-based adhesives, polyurethane-based adhesives, and the like can be used.

Examples of laminated films that can be applied to this embodiment include films having the following configurations.
(1) Transparent deposition PET/heat generating ink layer/pattern layer/sealant layer/ONy/sealant layer/CPP
(2) ONy/heat generating ink layer/picture layer/sealant layer/transparent deposition PET/sealant layer/CPP
(3) Transparent deposition PET/heat-generating ink layer/pattern layer/PET/sealant layer/CPP
(4) Transparent deposition PET/heat generating ink layer/picture layer/sealant layer/PET/sealant layer/PET/sealant layer/CPP
(5) Transparent vapor-deposited PET/pattern layer/heat-generating ink layer/sealant layer/ONy/sealant layer/CPP
(6) ONy/pattern layer/heating ink layer/sealant layer/transparent deposition PET/sealant layer/CPP
(7) Transparent deposition PET/pattern layer/heat-generating ink layer/PET/sealant layer/CPP
(8) Transparent deposition PET/picture layer/heat-generating ink layer/sealant layer/PET/sealant layer/PET/sealant layer/CPP

[Seal part]
A seal portion 50 is formed by heat-sealing the vicinity of the periphery of the sheet 11 made of the laminated film 30 . When viewed from the direction shown in FIG. 1 , the seal portion 50 surrounds the housing space 2 and seals the housing space 2 .

The form of the seal portion in the pouch of the present invention will be described below with reference to examples.
<First embodiment>
In the pouch according to the first embodiment, the outer edge 50a of the seal portion 50 extends circumferentially along the edges 12 to 14 of the sheet 11, as shown in FIG. On the other hand, the inner edge 50b of the seal portion 50 extends circumferentially while being spaced apart from the outer edge 50a.

The seal portion 50 includes a first side seal portion 51 and a second side seal portion 52 that face each other in the lateral direction d1, and an upper seal portion 53 and a lower seal portion 54 that face each other in the vertical direction d2 orthogonal to the lateral direction d1. In other words, the horizontal direction d1 is the direction in which the first side seal portions 51 and the second side seal portions 52 are arranged, and the vertical direction d2 is the direction perpendicular to the arrangement direction.

The side seal portions 51 and 52 are formed by heat-sealing the vicinity of the side edges 13 of the two sheets 11 . The upper seal portion 53 is formed by heat-sealing the vicinity of the upper edge 12 of the sheet 11 . The lower seal portion 54 is formed by heat-sealing the vicinity of the lower edge 14 of the sheet 11 .

FIG. 3 is an enlarged view of the first side seal portion near the overhang seal portion in the pouch according to the first embodiment. As shown in FIG. 3 , the first side seal portion 51 is composed of a side end seal portion 56 and an overhang seal portion 55 .
The side end seal portions 56 are formed by heat-sealing the vicinity of the side edges 13 of the sheet 11 (laminated film 30). That is, the side end seal portion 56 is located on the side edge 13 side of the sheet 11 (laminated film 30 ) with respect to the accommodation space 2 . The side end seal portion 56 extends in the vertical direction d2 of the pouch 1 and connects to the upper seal portion 53 and the lower seal portion 54 .

1 and 3, the width of the side end seal portion 56 on the upper seal portion 53 side (the width in the direction from the accommodation space 2 toward the outside of the pouch) is larger than the width of the side end seal portion 56 on the lower seal portion 54 side (the width in the direction from the accommodation space 2 toward the outside of the pouch). This is a configuration that takes into consideration the ease of handling when the package is opened from a notch described later after heating. However, the present embodiment is not limited to this, and the side end seal portion 56 may have the same width from the upper seal portion 53 to the lower seal portion 54 .

In the present embodiment, the position where the projecting seal portion 55 is provided is not particularly limited, but it is preferably provided at a position that does not come into contact with the contents during heating in the microwave oven. For example, when the pouch 1 is heated with the lower seal portion 54 facing downward, the overhang seal portion 55 is preferably provided above the first side seal portion 51 (near the upper seal portion 53).

1 and 3, the overhang seal portion 55 has a pair of projecting portions 57 (57a, 57b). The projecting portions 57 a and 57 b each extend from the inner edge 21 of the side seal portion 51 toward the housing space 2 . That is, the projecting portions 57 a and 57 b connect the first side seal portion 51 and the side edge 13 on the side opposite to each other, and protrude toward the housing space 2 beyond the side end seal portion 56 . 1 and 3, the projections 57a and 57b have a rectangular shape when the pouch 1 is viewed from above. The tips of the projections 57a and 57b may have corners or may be curved in a fan shape. As shown in FIGS. 1 and 3, the projections 57a and 57b preferably have the same shape and size, but may be different.
In addition, planar view means viewing the pouch 1 from a direction orthogonal to both the horizontal direction d1 and the vertical direction d2 in the drawing.

As shown in FIGS. 1 and 3, the protruding portions 57a and 57b are spaced apart from each other and are arranged in the longitudinal direction of the side end seal portion 56 (the direction extending from the upper seal portion 53 to the lower seal portion 54, the vertical direction d2 in FIG. 3). The inner edge 21 of the side end seal portion 56 faces the accommodation space 2 between the pair of projecting portions 57a and 57b.

As shown in FIGS. 1 and 3, the upper side end seal portion 56 is formed with a notch 7 that can serve as a starting point for opening. The position where the notch 7 is provided is the planned opening position when the pouch 1 is to be opened in order to take out the contents accommodated in the accommodation space 2 . Notch 7 penetrates sheet 11 . The notch 7 may be a cut formed in the side end seal portion 56, or may be a notch having a predetermined width. Due to the formation of the notch 7 in the side end sealing portion, opening of the pouch 1 can be easily started from the notch 7 .
Notch 7 is preferably provided in at least one of first side seal portion 51 and second side seal portion 52 . For example, as shown in FIG. 1, the notch 7 may be provided not only in the first side seal portion 51 but also in the second side seal portion 52 . In this case, the positions where the two notches 7 are formed are preferably at substantially the same height in the vertical direction d2 of the pouch 1. As shown in FIG.
Note that the notch 7 may be formed in the lower side end seal portion 56 .

The planned unsealing position is not limited to the notch 7, and various known easy-sealing means can be provided. As another easy-to-open means, there is an example of providing a plurality of fine small holes.

In this embodiment, it is not necessary to provide an unsealed area on the side edge side of the sheet, which is formed in the pouches of Patent Documents 2-4.

In this embodiment, the heat-generating ink layer is provided at least in the region between the tip portions 58 (58a, 58b) of the pair of projecting portions 57 (57a, 57b), including the side end seal portions 56. As shown in FIG.
In FIG. 3, the areas where the heat-generating ink layers are provided are indicated by oblique lines. In the example shown in FIG. 3, the area in which the heat-generating ink layer is provided is rectangular in plan view.

One end in the horizontal direction d1 of the region where the heat-generating ink layer is provided is provided so as to reach the side edge 13 of the first side seal portion 51 (the edge of the first side seal portion 51 on the side opposite to the accommodation space 2).
Even if the heat-generating ink layer is not provided in the vicinity of the side edge 13 of the first side seal portion 51, as long as the area of the heat-generating ink layer of the first side seal portion 51 is sufficiently secured, the sheet peeling effect described later can be obtained.

The other end in the lateral direction d1 of the region where the heat-generating ink layer is provided reaches the inner edge of the first side seal portion 51 on the accommodation space 2 side. In FIG. 3 , since the side end seal portion 56 faces the housing space 2 between the pair of projecting portions 57 , the region where the heat generating ink layer is provided is provided so as to reach the inner edge 21 of the side end seal portion 56 .
Even if the heat-generating ink layer is not provided so as to reach the inner edge of the first side seal portion 51, if it is provided up to the vicinity of the inner edge, the sheet peeling effect described later can be achieved.

Both ends in the vertical direction d2 of the region where the heat-generating ink layer is provided are located in regions between the pair of projecting portions 57 (57a, 57b).

In FIG. 3, the heating ink layer is provided so as to form a rectangular area, but the present embodiment is not limited to this. The area on which the exothermic ink layer is provided may have other shapes, such as triangular, trapezoidal, oval, etc., as long as it satisfies the application area requirements described above.

When steam is generated from the contents by heating, the accommodation space 2 expands. The storage space 2 can be considered to expand from the vicinity of the center of the pouch 1 . Therefore, the pressure applied to the seal portion 50 depends on the distance from the vicinity of the center of the pouch 1, and the closer the pouch 1 is to the center, the stronger the steam load the seal portion receives.
On the other hand, during heating in the microwave oven, the side end sealing portion 56 provided with the heat-generating ink layer is heated by the conductive polymer and conductive particles in the heat-generating ink. As a result, the bonding strength of the sheet 11 at the side end seal portions 56 is reduced relatively early after heating in the microwave oven. Therefore, when the pressure in the accommodation space 2 increases, the sheet 11 peels off at the side end seal portions 56 where the joining force is weakened. Then, the steam in the housing space 2 is released to the outside of the pouch 1 from the peeled portion.
In this way, the pouch of the present embodiment reliably causes peeling of the sheet 11 in the region where the heat-generating ink layer of the side end seal portion 56 is provided during microwave heating, and the steam in the storage space 2 can escape to the outside. The pouch of the present embodiment is capable of allowing steam to escape even when containing contents that generate a small amount of steam.

In this embodiment, since the heat-generating ink layer is formed on the first side seal portion 51 (side end seal portion 56), even when the pouch 1 is heated in an upright state using a flat table microwave oven, the contents do not prevent the microwaves from reaching the heat-generating ink layer. Therefore, the pouch 1 of the present embodiment can reliably generate steam escape in the region where the heat-generating ink layer is provided, regardless of the heating method of the microwave oven used.

It is designed so that when heat-sealed under the same conditions, the bonding force at an arbitrary point in the seal portion 50 is equal to the bonding force at another point. However, a distribution of bonding force may occur within the seal portion 50 during heat sealing. If the heat-generating ink layer is not provided, when the pressure in the housing space rises due to heating in the microwave oven, there is a possibility that the sealing portion with weak joining force other than the overhanging sealing portion may cause the seal to retreat. As in the present embodiment, since the heat-generating ink layer including the side end seal portion is provided in the region between at least the tip end portions of the pair of protrusions, the bonding force of the sheet 11 at the side end seal portion 56 can be reduced, and the effect of suppressing the seal retreat at the other seal portions is also exhibited.
Since the retraction of the seal can be suppressed in this manner, the width of the seal portion 50 can be made smaller than in the conventional pouch in the pouch of the present embodiment. Specifically, the width of the seal portion 50 can be about 4 mm. As a result, the size of the bag can be reduced. Alternatively, the size of the outer circumference can be the same, and the volume of the accommodation space can be increased.

If the contents contain a lot of liquid, the liquid will boil as well as steam during microwave heating. For example, when the pouch 1 is placed upright and heated in a microwave oven, the liquid not only boils up from below the accommodation space 2, but also reaches the upper part of the accommodation space 2 (upper sealing portion 53 when the pouch is upright) and falls downward. When the protruding seal portion 55 is provided, the boiling content is restricted from reaching the side end seal portion 56 between the protruding portions 57a and 57b, so that the content can be prevented from being ejected to the outside of the pouch 1 through the peeled portion of the side end seal portion 56.

The amount of heat generated by the heat-generating ink layer depends on the content of the microwave-absorbing material in the applied heat-generating ink. That is, the amount of heat generated depends on the area of the region where the heat-generating ink layer is provided, particularly when the pouch 1 is viewed from above. The area is appropriately set in consideration of the peelability of the side end seal portion, the manufacturing cost, and the like. When the pouch is viewed from above, the area of the region where the heat-generating ink layer is provided is preferably 0.3 cm ² to 4.5 cm ² , more preferably 0.4 cm ² to 3.0 cm ² .

In the present embodiment, the spacing in the direction in which the pair of projections 57a and 57b are arranged (vertical direction d2 in FIG. 3) is not particularly limited. On the other hand, if the distance between the projecting portions 57a and 57b is large relative to the length of the first side seal portion 51, the projecting portions 57a and 57b may not be able to exhibit a sufficient ejection suppressing effect. From this point of view, the interval is preferably 20 mm or less, more preferably 15 mm or less. Also, the ratio of the gap to the length of the first side seal portion 51 is preferably 1/5 or less, preferably 1/7 or less.
The distance between the protrusions refers to the distance between the closer ends of the sides where the protrusions and the side end seal portions are connected when the pouch is viewed from above.

The length of the region where the heat-generating ink layer is provided (the length d2 in the vertical direction in FIG. 3) affects vapor permeability, prevention of leakage of contents, production cost, and the like. If the length of the region where the heat-generating ink layer is provided is large, the amount of heat-generating ink applied increases, which increases the production cost. If the length of the region where the heat-generating ink layer is provided is short, the force of the steam in the storage space 2 blows out when the sheet 11 is peeled off, and there is a risk that the contents will blow out of the pouch 1 along with the steam. In addition, since the area of the region where the heat-generating ink layer is provided is small, the side end sealing portion 56 cannot be sufficiently heated, and there is concern that peeling may not occur. From this point of view, the length of the region in which the heat-generating ink layer is provided in the first direction is preferably 1 to 20 mm, more preferably 4 to 15 mm.
In addition, the heat-generating ink layer may be applied solidly within the region where it is formed, or may be applied in a grid pattern or the like.

In the present embodiment, the length of the protruding portions 57a and 57b (the length of the lateral direction d1 from the inner edge 21 of the side end seal portion 56 to the distal end portions 58a and 58b) is not particularly limited, but is appropriately set in consideration of the volume of the storage space 2 and not becoming an obstacle when the content is filled. In particular, the length of the protruding portions 57a and 57b is preferably 1 to 20 mm, more preferably 1 to 10 mm, from the viewpoint of obtaining an effect of suppressing the ejection of contents during microwave heating, as will be described later. Also, the ratio (L2/L1) of the length L2 of the projections 57a and 57b to the distance L1 between the pair of projections is preferably 0.2 to 1.5, more preferably 0.3 to 1.0.

As described above, the pouch of the present embodiment has a simpler shape of the overhang seal portion than those of Patent Documents 2 to 4, and does not have an unsealed area. Therefore, compared with the pouches having unsealed areas disclosed in Patent Documents 2 to 4, it has the advantage of being able to increase the volume of the containing space and being less likely to become an obstacle during filling. In addition, it is possible to suppress contamination by foreign matter. Furthermore, it has a manufacturing merit that the bag-making process of the pouch is easy.

FIG. 4 is a diagram explaining a modification of the first embodiment. In FIG. 4, the same components as in FIG. 3 are assigned the same reference numerals. In FIG. 4, the area where the heat-generating ink layer is provided is indicated by oblique lines.
In the example shown in FIG. 4, the area where the heat-generating ink layer is provided is rectangular in plan view, and one end in the horizontal direction d1 is provided in a part of the housing space 2 beyond the inner edge 21 of the side end seal portion 56 (the inner edge of the first side seal portion 51 on the side of the housing space 2). With such a configuration, the area of the region where the heat-generating ink layer is provided can be increased, so that the side edge sealing portion 56 can be heated so that the joining force of the sheet 11 is sufficiently reduced. Furthermore, it is possible to allow production tolerances such as misprinting of the heat-generating ink layer and seal misalignment. On the other hand, if the area of the heat-generating ink layer formed in the accommodation space 2 becomes large, the sheet may be excessively heated and shrinkage of the sheet may occur. In addition, the production cost increases, and the heat-generating ink layer stands out, which may deteriorate the design. Considering the above, it is preferable that the heat-generating ink layer formed in the accommodation space 2 is formed within a region of 5 mm or less from the inner edge 21 of the side end seal portion 56 .

<Second embodiment>
FIG. 5 is an enlarged view of the first side seal portion near the overhang seal portion of the pouch according to the second embodiment. In FIG. 5, the same reference numerals are assigned to the configurations common to those in FIG.

The second embodiment is the same as the first embodiment except for the shape of the overhang seal portion.
The projecting seal portion 155 in FIG. 5 is a right-angled triangle when the pair of projecting portions 155 (155a, 155b) is viewed from above. The pair of protruding portions 155 (155a, 155b) are spaced apart from each other and arranged in the longitudinal direction of the side end seal portion 56. As shown in FIG. The inner edge 21 of the side end seal portion 56 (the inner edge of the first side seal portion 51) faces the accommodation space 2 between the pair of projecting portions 155 (155a, 155b).

One of the two perpendicular sides of the projecting portions 155a and 155b is connected to the inner edge 21 of the side end seal portion 56 on the accommodation space 2 side (the inner edge on the side opposite to the side edge 13 of the laminated film 30). Of the two sides, the other side protrudes in the lateral direction d1 from the side end seal portion 56 toward the housing space 2 side. The tips of the projections 155a and 155b may have corners as shown in FIG. 5, or may be curved in a fan shape.
In FIG. 5, the oblique sides of protrusions 155a and 155b are arranged to face each other. As a modification of FIG. 5, the projecting portions 155a and 155b may be arranged such that the sides projecting in the horizontal direction d1 toward the accommodation space 2 face each other and the oblique sides face the upper seal portion 53 and the lower seal portion 54.
The shape and size of the pair of protrusions 155a and 155b are preferably the same, but may be different.

FIG. 5 is an example, and the shape and size (the angle of the vertex and the length of the side) of the protrusion are not particularly limited as long as the protrusion is triangular. For example, the protrusion may be an isosceles triangle, an equilateral triangle, or the like. The shape and size of the protruding portion are appropriately set in consideration of the volume of the space 2, not becoming an obstacle when the content is filled, the effect of suppressing the ejection of the content, and the like.

In FIG. 5, the width of the side end seal portion 56 is the same from the upper seal portion 53 toward the lower seal portion 54, but the present embodiment is not limited to this. As shown in FIG. 3, it is also possible to design the width of the side end seal portion 56 near the upper seal portion 53 to be wide in consideration of the handleability when unsealing after heating.

In this embodiment, the heat-generating ink layer is provided at least in the region between the tip portions 158a, 158b of the pair of protruding portions 155a, 155b, including the side end seal portion 56. As shown in FIG.
In FIG. 5, the region where the heat generating ink layer is provided is indicated by oblique lines. In the example shown in FIG. 5, the area where the heating ink layer is provided is rectangular in plan view.
As in FIG. 3, the heat-generating ink layer is provided in the region between the pair of protrusions 155a and 155b within the side end seal portion 56. As shown in FIG.
In FIG. 5, the exothermic ink layer is provided so as to reach the side edge 13 of the side seal portion 51 . Further, the heat-generating ink layer is provided so as to reach the inner edge 21 (the inner edge of the first side seal portion 51) of the housing space 2 of the side end seal portion 56. As shown in FIG. As a modification of FIG. 5, the heat-generating ink layer may be provided in part of the housing space 2 beyond the inner edge 21 of the side end seal portion 56 as shown in FIG.

FIG. 6 is a modified example of the second embodiment, and is an enlarged view of the first side seal portion near the overhang seal portion. In FIG. 6, the same reference numerals are assigned to the configurations common to those in FIGS.

In FIG. 6, the area where the heat-generating ink layer is provided is indicated by oblique lines. In the example shown in FIG. 6, the area where the heating ink layer is provided is triangular (isosceles triangle) when viewed from above.
The bottom edge of the area coincides with the side edge 13 of the first sealing area 51 . That is, the heat-generating ink layer is provided so as to reach the edge of the side seal portion 51 on the side opposite to the housing space 2 . The length of the bottom may be greater than the distance between protrusions 157a and 157b, as shown in FIG.
The apex angle is provided within the housing space 2 when viewed from above. Therefore, the heat-generating ink layer in FIG. 6 is provided beyond the inner edge of the side end seal portion 56 (side seal portion 51). In FIG. 6, the heating ink layer is not provided on the projecting portions 157a and 157b.

Thus, in this embodiment, the shape of the region where the heat-generating ink layer is provided is not particularly limited. The area on which the exothermic ink layer is provided may have other shapes such as trapezoidal, elliptical, etc., as long as the requirements for the coating area described above are satisfied.

By providing the heat-generating ink layer as shown in FIGS. 5 and 6, it is possible to reliably reduce the bonding force of the sheet in the heat-generating ink layer formation region of the side end seal portion and cause the sheet to peel when heated in the microwave oven. For this reason, it is possible to achieve the effect of suppressing seal retreat at other seal portions.
Furthermore, by providing a pair of protrusions so as to sandwich the heat-generating ink layer forming region, it is possible to suppress the ejection of the contents during heating in the microwave oven.

In the first and second embodiments, the projections are rectangular and triangular, respectively, but the present invention is not limited to this. For example, other shapes such as trapezoids, pentagons, and other polygons can be applied as long as the above-described effects of the present invention are achieved.

<Third Embodiment>
FIG. 7 is an enlarged view of the first side seal portion near the overhang seal portion in the pouch according to the third embodiment. In FIG. 7, the same reference numerals are assigned to the configurations common to those in FIG.

The third embodiment is the same as the first embodiment except for the shape of the overhang seal portion.
A pair of projections 257 (257a, 257b) of the overhang seal portion 255 in FIG. The inner edge 21 of the side end seal portion 56 (the inner edge of the first side seal portion 51) faces the housing space 2 between the pair of projecting portions 257 (257a, 257b).
The protruding seal portion in the third embodiment has an arcuate shape protruding toward the housing space 2 from the side end seal portion, and does not have a corner region. In the example shown in FIG. 7, the tip portions 258a and 258b of the projecting portions 257a and 257b are semi-elliptical in plan view, and the long axis substantially coincides with the vertical direction d2 (first direction). In the example of FIG. 7 , the protrusions 257 a and 257 b have a shape that combines a semi-ellipse and a rectangle, and the rectangular portions are connected to the side end seal portions 56 .

FIG. 7 is an example, and the shape and size of the protrusion are not particularly limited as long as the tip of the protrusion has an arc shape. For example, the long and short axis portions of the semi-elliptical protrusion may be connected to the side end seal portions. Also, the tip of the protruding portion may be a semicircle or an asymmetrical arc when viewed from above. The size of the protruding portion is appropriately set in consideration of the capacity of the storage space 2, not becoming an obstacle when the content is filled, the effect of suppressing the ejection of the content, and the like.
The shape and size of the pair of protrusions 257a and 257b are preferably the same, but may be different.

In this embodiment, the heat-generating ink layer is provided at least in the region between the tip portions 258a, 258b of the pair of protrusions 257a, 257b, including the side end seal portions 56. As shown in FIG.
In FIG. 7, the area where the heat-generating ink layer is provided is indicated by oblique lines. In the example shown in FIG. 7, the region in which the heat-generating ink layer is provided is rectangular in plan view.
Similar to FIG. 3, the heat-generating ink layer is provided in the region between the pair of protrusions 257a and 257b within the side end seal portion 56. As shown in FIG.
In FIG. 7, the heat-generating ink layer is provided so as to reach the edge portion 13 of the side seal portion 51 on the side opposite to the housing space 2 . Also, the heat-generating ink layer is provided so as to reach the inner edge 21 of the side end seal portion 56 . As a modification of FIG. 7, the heat-generating ink layer may be provided in part of the housing space 2 beyond the inner edge 21 of the side end seal portion 56 as shown in FIG.

FIG. 7 is merely an example, and the shape and size of the region where the heat-generating ink layer is provided are not particularly limited in this embodiment. For example, the area in which the heat-generating ink layer is provided may have other shapes, such as triangular, trapezoidal, and elliptical, as long as it satisfies the requirements of the coating area described above.

By providing the heat-generating ink layer as shown in FIG. 7, it is possible to reliably reduce the joining force of the sheet in the heat-generating ink layer formation region of the side end seal portion and cause the sheet to peel when heated in the microwave oven. For this reason, it is possible to achieve the effect of suppressing seal retreat at other seal portions.
Furthermore, by providing a pair of protrusions so as to sandwich the heat-generating ink layer forming region, it is possible to suppress the ejection of the contents during heating in the microwave oven.

If the overhanging seal portion has a shape that does not have a corner region as in the third embodiment, it is possible to achieve an advantageous effect that the bag can be prevented from breaking from the overhanging seal portion due to the impact when the pouch is dropped.

<Fourth Embodiment>

The fourth embodiment differs from the first to third embodiments in that a heat-generating ink layer is provided on part of the overhanging seal portion.
In this embodiment, the exothermic ink layer is provided including the region between the pair of protrusions, a portion of each protrusion, and the side edge seal portions 56 .

Here, a pouch having an overhang seal portion having the same shape as that of FIG. 5 will be described as an example. FIG. 8 is an enlarged view of the first side seal portion near the overhang seal portion in the pouch according to the fourth embodiment. In FIG. 8, the same reference numerals are assigned to the configurations common to those in FIG.
In FIG. 8, the area where the heat-generating ink layer is provided is indicated by oblique lines. In the example shown in FIG. 8, the area where the heat generating ink layer is provided is rectangular in plan view. The heat-generating ink layer is provided including the areas on the oblique sides of the protrusions 158a and 158b, but is not provided at the tips of the protrusions 158a and 158b.

In FIG. 8, the heat-generating ink layer is provided so as to reach the edge portion 13 of the side seal portion 51 on the side opposite to the accommodation space 2 . Further, the heat-generating ink layer is provided so as to reach the inner edge 21 (inner edge of the first side seal portion 51 ) of the housing space 2 of the side end seal portion 56 . As a modification of FIG. 7, the heat-generating ink layer may be provided in part of the housing space 2 beyond the inner edge 12 of the side end seal portion 56 as shown in FIG.

FIG. 8 is merely an example, and the shape and size of the region where the heat-generating ink layer is provided are not particularly limited in this embodiment. For example, the area in which the heat-generating ink layer is provided may have other shapes, such as triangular, trapezoidal, and elliptical, as long as it satisfies the requirements of the coating area described above.

By providing the heat-generating ink layer as shown in FIG. 8, it is possible to reliably reduce the joining force of the sheet in the heat-generating ink layer formation region of the side end seal portion and cause the sheet to peel when heated in the microwave oven. In the configuration of the present embodiment, since a sufficient area can be secured for the region where the heat-generating ink layer is provided, it is possible to reliably release the steam in the accommodation space from the peeled portion. Therefore, it is possible to reliably obtain the effect of suppressing the seal from retreating at other seal portions.
Furthermore, by providing a pair of protrusions so as to sandwich the heat-generating ink layer forming region, it is possible to suppress the ejection of the contents during heating in the microwave oven. In this embodiment, the exothermic ink layer is also provided on the protruding portion, but since the exothermic ink layer is not provided on the tip portion, for example, the effect of suppressing the ejection of the contents is reduced compared to the embodiments of FIGS.

<Fifth Embodiment>
FIG. 9 is an enlarged view of the first side seal portion near the overhang seal portion in the pouch according to the fifth embodiment. In FIG. 9, the same reference numerals are assigned to the configurations common to those in FIG.
In the fifth embodiment, a pair of projecting portions 357 (357a, 357b) are arranged in the longitudinal direction of the side end seal portion 56 and are provided so as to contact each other. In the fifth embodiment, the inner edge of the side end seal portion is not exposed to the housing space 2 between the protrusions 357a and 357b.
In the example of FIG. 9, the projecting seal portion 355 is a right-angled triangle when the pair of projecting portions 357 (357a, 357b) are viewed from above. 5, one side of the two sides forming a right angle of the projections 357a and 357b is connected to the inner edge 21 of the side end seal portion 56, and the other side protrudes from the side end seal portion 56 toward the accommodation space 2 side in the horizontal direction d1. The oblique sides of the protruding portions 357a and 357b are arranged to face each other, and the protruding portions 357a and 357b are in contact with each other at the bottom corners. The shape and size of the pair of protrusions 357 (357a, 357b) are preferably the same, but may be different.

FIG. 10 is a modified example of the fifth embodiment, and is an enlarged view of the first side seal portion near the overhang seal portion. In FIG. 10, the same reference numerals are assigned to the configurations common to those in FIGS.
In the example of FIG. 10, the projecting seal portion 455 is connected such that a pair of right-angled triangular projecting portions 457 (457a, 457b) overlap each other when viewed from above. Therefore, a connecting region 459 is formed in a region between the distal end portions 458a and 458b of the projecting portions 457a and 457b when viewed from above. The connecting region 459 is positioned closer to the accommodation space 2 than the inner edge 21 of the side end seal portion 56 . Therefore, the width (the width in the lateral direction d1) of the overlapping portion (connecting region 459) of the projecting portion 457 is larger than the width of the side end seal portion 56. As shown in FIG.
The shape and size of the pair of protrusions 457a and 457b are preferably the same, but may be different.

In this embodiment, the heat-generating ink layer is provided at least in the region between the tips of the pair of protrusions, including the side end seal portions 56 . Since the protrusions connect, some of the protrusions are provided with a heat-generating ink layer, but not each of the tip portions.
In FIGS. 9 and 10, hatched areas indicate areas where the heat-generating ink layer is provided. In the examples shown in FIGS. 9 and 10, the area where the heating ink layer is provided is rectangular in plan view.

In FIG. 9, the heat-generating ink layer is provided so as to reach the edge portion 13 of the side seal portion 51 on the side opposite to the accommodation space 2 . Also, the heat-generating ink layer is provided on partial regions of the protrusions 355a and 355b. Therefore, the heat-generating ink layer protrudes from the side end seal portion 56 and the projecting portion 355 and is provided in part of the housing space 2 . However, the exothermic ink layer is not provided on the tip portions 358a, 358b of the projecting portions 357a, 357b.

In FIG. 10, the heat-generating ink layer is provided so as to reach the edge portion 13 of the side seal portion 51 on the side opposite to the accommodation space 2 . Also, the heat-generating ink layer is provided on the connecting region 459 and partial regions of the projecting portions 455a and 455b. The heat-generating ink layer protrudes from the connection region 459 and is provided in part of the housing space 2 . That is, the heat-generating ink layer is provided in part of the accommodation space 2 beyond the inner edge of the first side seal portion 51 on the accommodation space 2 side. However, the exothermic ink layer is not provided on the tip portions 457a and 458b of the projecting portions 457a and 457b.

In the present embodiment, when the direction in which the pair of protrusions are arranged is defined as the first direction, the width of the region in which the heat-generating ink layer is provided in the first direction (the width in the vertical direction d2 in FIGS. 9 and 10) is provided in a region having a ratio of 0.1 to 0.8 of the width of the overhanging seal portions 355 and 455 in the first direction.

Also in this embodiment, by providing the heat-generating ink layer, it is possible to reliably reduce the joining force of the sheet in the heat-generating ink layer formation region of the side end seal portion and cause the sheet to peel when heated in the microwave oven. For this reason, it is possible to achieve the effect of suppressing seal retreat at other seal portions.
By providing the heat-generating ink layer with the width of the above ratio, when the accommodation space is not exposed between the protrusions, especially when the width of the side seal portion 51 in the region between the protrusions becomes larger than the width of the side end seal portion 56 as shown in FIG.

Furthermore, since the pair of protrusions are provided so as to sandwich the heat-generating ink layer forming region, it is possible to suppress the ejection of the contents during heating in the microwave oven. In this embodiment, since no heat-generating ink layer is provided at the tip of the protruding portion, the effect of suppressing the ejection of the contents is not deteriorated as compared with the embodiments of FIGS. 5 and 6, for example.

9 and 10 are examples, and the shape of the protrusion is not particularly limited in this embodiment. For example, the protrusions may be trapezoidal, elliptical, circular, or the like. The size of the protruding portion is not particularly limited, but it is appropriately set in consideration of the volume of the space 2, not becoming an obstacle when the content is filled, and the effect of suppressing the ejection of the content.
However, this embodiment excludes the case where the two tips are connected in such a way that they cannot be recognized. For example, if two right-angled triangles are arranged so that their hypotenuses face the upper seal portion 53 and the lower seal portion 54, they are regarded as one triangle and have only one tip, and are excluded from the present embodiment.

In this embodiment, the shape of the region where the heat-generating ink layer is provided is not particularly limited. The area in which the exothermic ink layer is provided may have other shapes as long as the requirements for the coating area described above are satisfied.

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited by these examples.
[Preparation of sample]
<Example 1>
1. Production of Laminated Film An alumina-deposited PET film (thickness: 12 μm) was prepared as a substrate layer. An ink containing a conductive polymer (manufactured by Tokyo Ink Co., Ltd., product number MW heat agent) was gravure-printed on the deposition surface side of the substrate layer and dried to form a 1 μm-thick exothermic ink layer. Note that the heat-generating ink layer is described in Item 2. It was formed by patterning so as to be formed at the location described in .
Next, an intermediate base layer (stretched Ny, thickness 15 μm) was laminated by a dry lamination method using a urethane-based two-liquid curing adhesive (RU-004/H-1, manufactured by Rock Paint Co., Ltd.) on the side of the base layer on which the exothermic ink layer was formed.
Next, a sealant layer (CPP, thickness 70 μm) was laminated on the intermediate substrate layer (stretched Ny) by a dry lamination method using the above adhesive to obtain a laminated film.

2. Preparation of Pouch A pair of sheets was obtained from the laminated film described above. The two sheets were superimposed and the side edges and lower edges were heat-sealed to obtain a flat bag-type pouch (the upper edge is an opening that is not heat-sealed) having the shape shown in FIG. Dimensions are given below for the side edge seal portions and the overhang seal portions. The volume of the pouch housing space was 420 cm ³ .
(Side end seal part)
Width on the side of the upper seal portion 53 (width in the lateral direction d1 from the pouch edge portion 13): 10 mm
Width on the lower seal portion 54 side (width in the lateral direction d1 from the pouch edge 13): 6 mm
Width in region between protrusions (width in lateral direction d1 from pouch edge 13): 6 mm
(Overhang seal part)
Length of protrusions 57a and 57b (length in lateral direction d1 from inner edge 21 of side end seal portion between protrusions): 10 mm
Width of protrusions 57a and 57b (length in vertical direction d2 (first direction)): 3 mm
Spacing between protrusions 57a and 57b: 15 mm

The heat sealing conditions were as follows.
・Temperature: 180℃
・Time: 1.5 seconds ・Pressure: 2.0 MPa (air cylinder type)

In Example 1, as shown in FIG. 3, a heat-generating ink layer having a rectangular shape when viewed from above was formed. The width of the heating ink layer in the vertical direction d2 (first direction) was 10 mm.

Water (160 g) was contained as a content in the pouch, and the opening at the upper edge was heat-sealed to obtain a pouch of Example 1.

<Example 2>
A pouch (flat bag type pouch) of Example 2 was obtained in the same steps as in Example 1, except that a heat-generating ink layer was formed at the location shown in FIG. The region in which the heat-generating ink layer was formed had a rectangular shape with a width of 10 mm in the vertical direction d2 (first direction) and a width of 10 mm in the horizontal direction d1 from the side edge 13 .

<Example 3>
Using the same laminated film as in Example 1, a flat bag-type pouch having an overhang seal portion having the shape shown in FIG. 5 was obtained. The width of the side end seal portion was 6 mm from the upper seal portion 53 to the lower seal portion 54 . Dimensions are listed below for the overhang seal portion. The volume of the pouch housing space was 420 cm ³ .
(Overhang seal part)
Length of protrusions 157a and 157b (length in lateral direction d1 from inner edge 21): 7 mm
Angle of tips 158a, 158b: 45°
Spacing between protrusions 157a and 157b: 10 mm

The shape of the region where the heat-generating ink layer was formed was rectangular, and the width in the vertical direction d2 (first direction) was 7 mm.

<Example 4>
Using the same laminated film as in Example 1, a flat bag-type pouch having an overhang seal portion having the shape shown in FIG. 7 was obtained. The width of the side end seal portion was 6 mm from the upper seal portion 53 to the lower seal portion 54 . Dimensions are listed below for the overhang seal portion. The volume of the pouch housing space was 420 cm ³ .
(Overhang seal part)
Shape of protrusion: Semi-elliptical arc at the tip (major axis coincides with vertical direction d2), rectangular connecting part with side end seal part Dimensions of semi-elliptical arc part: major axis 3 mm, minor axis 2 mm
Dimensions of rectangular portion: 3 mm in length in horizontal direction d1 from inner edge 21, 6 mm in length in vertical direction d2 (first direction)
Spacing between protrusions 257a and 257b: 15 mm

The shape of the region where the heat-generating ink layer was formed was rectangular, and the width in the vertical direction d2 (first direction) was 6 mm.

<Example 5>
Using the same laminated film as in Example 1, a flat bag-type pouch having an overhang seal portion having the shape shown in FIG. 9 was obtained. The width of the side end seal portion was 6 mm from the upper seal portion 53 to the lower seal portion 54 . Dimensions are listed below for the overhang seal portion. The volume of the pouch housing space was 420 cm ³ .
(Overhang seal part)
Length of protrusions 357a and 357b (length in lateral direction d1 from inner edge 21): 7 mm
Angle of tips 358a, 358b: 45°
Width of projecting seal portion 355 (length in vertical direction d2 (first direction)): 7 mm

The region in which the heat-generating ink layer was formed had a rectangular shape with a width of 10 mm in the vertical direction d2 (first direction) and a width of 10 mm in the horizontal direction d1 from the side edge 13 .

<Comparative Example 1>
A pouch (flat bag type pouch) of Comparative Example 1 was obtained in the same steps as in Example 1, except that the overhang seal portion and the heat-generating ink layer were not provided.

<Comparative Example 2>
A pouch (flat bag type pouch) of Comparative Example 2 was obtained in the same process as in Example 1, except that a heating ink layer of the same shape was provided on the first side seal portion at the same position as in Example 1 without providing an overhang seal portion.

[evaluation]
<Sealability evaluation>
The pouches of Examples and Comparative Examples were placed upright in a flat table microwave oven. After that, it was heated at 600 W for 180 seconds. After that, the pouch was taken out from the microwave oven, and the state of the sealed portion was visually observed. Twenty pouches were tested in each example and comparative example and evaluated according to the following criteria. Table 1 shows the results.
A: In all pouches, peeling was confirmed in the region where the heat-generating ink layer was formed, and there was no peeling or seal retraction at the seal portion other than the region where the heat-generating ink layer was formed.
B: Even one pouch in which the seal retreated was confirmed at the seal portion other than the region where the heat-generating ink layer was formed.
C: Even one pouch in which the seal retreated and the content leaked out during heating was confirmed in the sealed portion other than the region where the heat-generating ink layer was formed.

<Boilover evaluation>
While the pouches of Examples and Comparative Examples were heated under the above conditions, the state of boiling over through the region provided with the heat-generating ink layer was visually observed. Twenty pouches were tested in each example and comparative example and evaluated according to the following criteria. Table 1 shows the results.
A: Boil-over could not be confirmed in all pouches.
B: 1 to 4 pouches in which boiling over was confirmed.
C: Five or more pouches in which boiling over was confirmed.

In any of the examples, no seal recession of the seal portion was observed in areas other than the area where the heat-generating ink layer was formed. In addition, it was confirmed that the pouches of Examples released steam slowly from the region where the exothermic ink layer was formed relatively early during heating in the microwave oven. Furthermore, no ejection (blowing over) of the contents was confirmed.

Since the pouch of Comparative Example 1 was not provided with a heat-generating ink layer, leakage of the contents due to seal retreat and seal peeling was confirmed at various locations of the seal portion.

In the pouch of Comparative Example 2, it was confirmed that steam was gradually released from the region where the exothermic ink layer was formed relatively early during heating in the microwave oven, and no seal retreat was confirmed. However, it was confirmed that the content spouted from the region where the heat-generating ink layer was formed.

1 Pouch 2 Storage space 11 Sheet 30 Laminated film 31 Base layer 34 Sealant layer 36 Heat-generating ink layer 51 Side sealing part (first side sealing part)
55, 155, 255, 355, 455 overhang seal portion 56 side end seal portion 57, 157, 257, 357, 457 protrusion

Claims (7)

A pouch made by stacking and heat-sealing at least one laminated film having a sealant layer so that the sealant layer is on the inner layer side, and having a storage space for storing contents,
Having a side seal portion heat-sealed with the laminated film,
The side seal portion has a side edge seal portion located on the side edge side of the laminated film, and an overhang seal portion having a pair of protrusions connected to the side edge seal portion on the side opposite to the side edge of the laminate film and extending toward the accommodation space from the side edge seal portion, the protrusions being arranged in the direction in which the side edges extend,
At least one of the laminated films has a heat-generating ink layer outside the sealant layer,
The pouch, wherein the heat-generating ink layer is provided at least in a region between the tips of the pair of protrusions, including the side end seal portion. 2. The pouch according to claim 1, wherein the heat-generating ink layer is provided so as to reach the inner edge of the side seal portion on the accommodation space side. 3. The pouch according to claim 1, wherein the heat-generating ink layer is provided in a part of the storage space beyond the inner edge of the side seal portion on the storage space side. 4. The pouch according to any one of claims 1 to 3, wherein the exothermic ink layer is provided so as to reach the edge of the side seal portion opposite to the housing space. The pair of protrusions are separated from each other, and the inner edges of the side end seal portions face the accommodation space between the pair of protrusions,
The pouch according to any one of claims 1 to 4, wherein the exothermic ink layer is not provided on the pair of protrusions. The pair of protrusions are separated from each other, and the inner edges of the side end seal portions face the accommodation space between the pair of protrusions,
5. The pouch according to any one of claims 1 to 4, wherein the heat-generating ink layer includes part of the pair of protrusions and is formed so as not to be provided at the tips of the pair of protrusions. the pair of protrusions are in contact with each other;
When the direction in which the pair of protrusions are arranged is defined as the first direction,
The pouch according to any one of claims 1 to 4, wherein the width in the first direction of the region where the heat-generating ink layer is provided is provided in a region that is a ratio of 0.1 to 0.8 of the width in the first direction of the overhanging seal portion, and is not provided at each of the tip portions of the protrusions.