JP2022152606A - Self-standing packaging bag - Google Patents

Abstract

To propose a self-standing packaging bag that is acceptable as a paper container capable of storing food and can be heated as it is by a microwave oven in an unopened state.SOLUTION: A self-standing packaging bag 1 is obtained by making sealant layers 13 of a front face laminate 2 and a rear face laminate 3 each comprising a paper substrate 10, a gas barrier layer 12, and the sealant layer 13, face each other; inserting, between the sealant layers, a bottom material 4 comprising a gas barrier layer 16 and a sealant layer 17 without containing any paper while being bent by 180° making the sealant layer be outside; and thermally sealing a bottom seal part 5 and a side seal part 6. The self-standing packaging bag has such a feature that weight of the paper substrate is larger than 50% of a packaging bag total weight; each gas barrier layer contains no metal foil; and a steam passing-through mechanism 20 including a steam-venting seal part 21 automatically released by superheated steam generated during microwave heating is formed at the side seal part.SELECTED DRAWING: Figure 1

Description

The present invention relates to a self-supporting packaging bag, in particular, using paper exceeding 50% of the total weight, and having a steaming function that automatically releases water vapor even when heated in a microwave oven in an unopened state. It relates to a self-supporting packaging bag.

A self-supporting packaging bag is a packaging bag in which a bottom material is inserted between a top sheet and a back sheet to seal the periphery, and the bottom surface is formed when the contents are filled, so that the bag is self-supporting. Self-supporting packaging bags These bags are widely used as refill containers for various toiletry products because they are easy to display at stores and have good storage efficiency.

With the growing awareness of the adverse effects of plastic containers on the environment, various attempts have been made to replace conventional plastic containers with paper, a reproducible material. The same applies to self-supporting packaging bags.

The self-supporting bag described in Patent Document 1 is composed of two sheets for body portion formation, which are made of at least a paper base material and a paper base laminated sheet in which a heat adhesive resin layer is laminated as the innermost layer, on the heat adhesive resin layer surface. are arranged facing each other, and a bottom forming sheet made of a laminated sheet having at least a heat-adhesive resin layer as the innermost layer at the lower end between the body forming sheets is mountain-folded at the center with the innermost layer surface as the outer surface It is a self-supporting bag formed by inserting the sheet into the bag and heat-bonding the periphery, wherein the periphery is heat-bonded to the upper part of the two body forming sheets, and the tip is cut off to have a spout for pouring out the contents. This self-supporting bag is characterized by:

The self-supporting bag described in Patent Document 1 is a refillable liquid storage container having a spout. I have a need to In order to store food, it is necessary to use a laminate with gas barrier properties because long-term storage is required. In addition, in order to enable microwave heating in an unopened package, it is not possible to use aluminum foil, which is commonly used as a gas barrier laminate, and in addition, it is not possible to use a A steaming mechanism is required.

JP-A-2009-57071

The problem to be solved by the present invention is to propose a self-supporting packaging bag that is recognized as a paper container that can store food, and that can be heated in a microwave oven as it is in an unopened state. It is something to do.

As a means for solving the above-mentioned problems, the invention according to claim 1 has the sealant layers of the surface laminate and the back laminate each having a paper substrate, a gas barrier layer, and a sealant layer facing each other, and between them, A self-supporting packaging bag obtained by inserting a paper-free bottom material having a gas barrier layer and a sealant layer by folding it 180° with the sealant layer facing outward, and heat-sealing the bottom seal portion and the side seal portions, The weight of the paper substrate is more than 50% of the total weight of the packaging bag,
The gas barrier layer does not contain a metal foil, and the side seal portion is formed with a vapor passage mechanism including a vapor release seal portion that is automatically opened by superheated vapor generated during heating in a microwave oven. It is a self-supporting packaging bag.

The self-supporting packaging bag according to the present invention is recognized as a paper container because it contains more than 50% of the total weight of paper, does not contain metal foil in its layer construction, and has a vapor release seal that is automatically opened by superheated steam. Since a steaming mechanism including a part is formed, it can be heated in a microwave oven in an unopened state.

In the invention according to claim 2, the vapor passage mechanism includes a steam release seal portion projecting from the side seal portion into the inside of the packaging bag, and an unsealed portion formed outside the steam release seal portion and communicating with the outside. 2. The self-supporting packaging bag according to claim 1, wherein the unsealed portion is formed with a through-hole penetrating through the surface laminate and the back laminate in the thickness direction.

Further, the invention according to claim 3 is the self-supporting packaging bag according to claim 1 or 2, wherein the basis weight of the paper base material is 30 g/m ² or more and 200 g/m ² or less. .

Further, the invention according to claim 4 is the self-supporting packaging bag according to claim 3, wherein the paper base material has a basis weight of 50 g/m ² or more and 120 g/m ² or less.

Further, the invention according to claim 5 is characterized in that the gas barrier layer is an inorganic vapor-deposited film in which a metal oxide vapor-deposited layer is formed on a base film. It is a self-supporting packaging bag.

The self-supporting packaging bag according to the present invention is classified as a paper container because it uses more than 50% of the total weight of the container, and can be handled as a paper container. This has the effect of reducing the cost burden in the disposal stage after use.

When paper is also used as the bottom material, the laminate tends to be rigid, making it difficult to open the bottom during filling. In the self-supporting packaging bag according to the present invention, since paper is not used for the bottom material, the bottom is flexible, and the opening of the bottom is good at the time of filling. As for the drop resistance after filling and sealing, the flexible bottom material absorbs the impact, so the drop impact resistance is good.

The laminate does not contain metal foil, and the side seals are formed with a vapor passage mechanism that includes a steam release seal that is automatically opened by the superheated steam generated during heating in the microwave oven. , Even if the container is placed upright and unopened, it will not explode or explode even if it is directly heated in a microwave oven. This property is effective even when rapidly heated in a high-output commercial microwave oven used in convenience stores and the like.

FIG. 1 is a schematic plan view showing one embodiment of a self-supporting packaging bag according to the present invention. FIG. 2 is a perspective transparent view showing a state in which the self-supporting packaging bag shown in FIG. 1 is filled with contents and the top seal portion is heat-sealed. FIG. 3 is a cross-sectional explanatory view showing an example of the layer structure of the front and back laminate of the self-supporting packaging bag according to the present invention. FIG. 4 is a cross-sectional explanatory view showing another example of the layer structure of the front and back laminates of the self-supporting packaging bag according to the present invention. FIG. 5 is a cross-sectional explanatory view showing another example of the layer structure of the front and back laminates of the self-supporting packaging bag according to the present invention. FIG. 6 is a cross-sectional explanatory view showing an example of the layer structure of the bottom material of the self-supporting packaging bag according to the present invention.

A self-supporting packaging bag according to the present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic plan view showing one embodiment of a self-supporting packaging bag 1 according to the present invention. FIG. 2 is a perspective transparent view showing a state in which the self-supporting packaging bag 1 shown in FIG. 1 is filled with contents and the top seal portion 7 is heat-sealed. FIG. 3 is a cross-sectional explanatory view showing an example of the layer structure of the front and back laminates 2 and 3 of the self-supporting packaging bag 1 according to the present invention. FIG. 6 is a cross-sectional explanatory view showing an example of the layer structure of the bottom material 4 of the self-supporting packaging bag 1 according to the present invention.

The self-supporting packaging bag 1 according to the present invention has the surface laminate 2 and the back laminate 3 having at least a paper substrate 10, a gas barrier layer 12, and a sealant layer 13, respectively. A self-supporting package obtained by inserting a bottom material 4 having at least a gas barrier layer 16 and a sealant layer 17, with the sealant layer 17 facing outward, by bending it 180° and heat-sealing the bottom sealing portion 5 and the side sealing portion 6. is a bag. In the self-supporting packaging bag 1 according to the present invention, the weight of the paper base material 10 is more than 50% of the total weight of the packaging bag, the gas barrier layer 12 does not contain metal foil, and the side seal portion 6 has gas generated during microwave heating. It is characterized by forming a vapor passage mechanism 20 including a steam release seal portion 21 which is automatically opened by superheated steam.

A self-supporting packaging bag 1 according to the present invention is composed of a surface laminate 2 and a back laminate 3 containing a paper base material 10, and a bottom material 4 that does not contain paper. It is classified as a paper container because it is greater than 50% by weight. For this reason, compared with plastic containers, it is advantageous in terms of processing costs and the like.

The paper base material 10 preferably has a basis weight of 30 g/m ² or more and 200 g/m ² or less. More desirably, the basis weight is 50 g/m ² or more and 120 g/m ² or less. If it is less than 30 g/m ² , the thickness of the film must be increased accordingly, making it difficult to increase the ratio of paper to more than 50%. When the basis weight of the paper exceeds 200 g/m ² , the stiffness and heat insulating properties of the paper are affected, resulting in poor bag-making properties and uneconomical.

As the gas barrier layer 12, a gas barrier film such as a polyvinylidene chloride film, a polyvinyl alcohol film, an ethylene vinyl alcohol copolymer film, a gas barrier nylon film, a gas barrier polyethylene terephthalate (PET) film, or a base film such as a PET film can be used. Inorganic oxide deposited film in which inorganic oxide such as aluminum oxide and silicon oxide is deposited on the film, or polyvinylidene chloride coating, coating containing water-soluble resin and inorganic layered compound, metal alkoxide or its hydrolyzate and isocyanate compound A gas barrier coating layer such as a resin layer made of a film obtained by reacting can be used. Among them, an inorganic oxide vapor-deposited film obtained by vapor-depositing an inorganic oxide such as aluminum oxide or silicon oxide on a PET film can be preferably used.

As the sealant layer 13, polyolefin resins are generally used. Specifically, low density polyethylene resin (LDPE), medium density polyethylene resin (MDPE), linear low density polyethylene resin (LLDPE), ethylene- Ethylene-based resins such as vinyl acetate copolymer (EVA), ethylene-α-olefin copolymer, ethylene-methacrylic acid resin copolymer, blend resin of polyethylene and polybutene, homopolypropylene resin (PP), propylene- Polypropylene resins such as ethylene random copolymers, propylene-ethylene block copolymers and propylene-α-olefin copolymers are used.

As in the self-supporting packaging bag according to the present invention, in order to automatically open the steam release seal portion by superheated steam, a block polypropylene resin that can be stably steamed by cohesive peeling as a sealant layer is suitable. used.

FIG. 4 is a cross-sectional explanatory view showing another example of the layer structure of the front and back laminates 2 and 3 of the self-supporting packaging bag 1 according to the present invention. In this example, a base film 11 is used on the outermost surface in addition to the configuration shown in FIG. If the paper substrate 10 exists on the outermost surface, the outermost surface can be made of a synthetic resin film in this way when there is concern about the water resistance and the like.

Various synthetic resin films can be used as the material of the base film 11 . Specifically, low density polyethylene resin (LDPE), high density polyethylene resin (HDPE), linear low density polyethylene resin (LLDPE), polypropylene resin (PP), polyolefin resin such as polyolefin elastomer, polyethylene terephthalate resin (PET), polybutylene terephthalate resin (PBT), polyester resin such as polyethylene naphthalate resin (PEN), polymethyl methacrylate resin (PMMA), ethylene-vinyl acetate copolymer resin (EVA), ionomer resin, polybutene -based resin, polyacrylonitrile-based resin, polyamide-based resin such as nylon-6, nylon-66, polystyrene-based resin (PS), polyvinyl chloride resin (PVC), polyvinylidene chloride resin (PVDC), polycarbonate resin (PC), Synthetic resin films such as fluorine-based resins and urethane-based resins can be used.

FIG. 5 is a cross-sectional explanatory view showing another example of the layer structure of the front and back laminates 2 and 3 of the self-supporting packaging bag 1 according to the present invention. In this example, an adhesive resin layer 14 is inserted between the paper substrate 10 and the gas barrier layer 12 .

In preparing each laminate of the surface laminate 2, the back laminate 3, and the bottom material 4, each layer is laminated by a dry lamination method using a known adhesive or an extrusion lamination method using an adhesive resin. be able to. In the example shown in FIG. 5, an extrusion lamination method using polyethylene resin is used. Although adhesive layers are omitted in FIGS. 3 to 6, each layer is laminated by a dry lamination method using an adhesive.

FIG. 6 is a cross-sectional explanatory view showing an example of the layer structure of the bottom material 4 of the self-supporting packaging bag 1 according to the present invention. In this example, the gas barrier layer 16, the base film 15, and the sealant layer 17 are laminated together by a dry lamination method using an adhesive.

As the gas barrier layer 16, the same material as the gas barrier layer 12 used for the front and back laminates 2 and 3 can be used. can be preferably used.

As the base film 15, various synthetic resin films made of the same material as the base film 11 used for the front and back laminates 2 and 3 can be used. Depending on the three-layer structure, the base film 15 may be omitted.

As the sealant layer 17, the same material as the sealant layer 13 used for the front and back laminates 2 and 3 can be used. The self-supporting packaging bag according to the present invention will now be described in more detail based on examples and comparative examples.

<Example 1>
A paper having a basis weight of 104.7 g/m ² was used as the paper substrate. As a gas barrier layer, an inorganic deposition film (GL film manufactured by Toppan Printing Co., Ltd.) obtained by depositing aluminum oxide on a polyethylene terephthalate resin film (PET) having a thickness of 12 μm was used. A non-stretched polypropylene resin film (CPP) having a thickness of 60 μm was used as the sealant layer. The three layers were dry-laminated using a dry lamination adhesive to form a front/back laminate having a layer structure as shown in FIG.

As the bottom material, an inorganic vapor-deposited film (GL film manufactured by Toppan Printing Co., Ltd.) obtained by vapor-depositing aluminum oxide on a polyethylene terephthalate resin film (PET) having a thickness of 12 μm was used as a gas barrier layer. A nylon film having a thickness of 15 μm was used as the base film. A non-stretched polypropylene resin film (CPP) having a thickness of 60 μm was used as the sealant layer. The three layers were dry-laminated using a dry-laminate adhesive to form a bottom material having a layer structure as shown in FIG.

The sealant layers of the front and back laminates are opposed to each other, and the bottom material is inserted between them by bending it 180° so that the sealant layer is on the outside, and the peripheral edge is heat-sealed to form a self-supporting packaging bag as shown in FIG. made. The height dimension was 158 mm, the width dimension was 152 mm, and the height of the bottom material was 45 mm. The weight of paper in the total weight of the packaging bag was 52%, and the weight of plastic was 48%.

A packaging bag was filled with 400 cc of water, and the bottom openability at the time of filling was confirmed. A case where the bottom opened smoothly and there was no problem with filling was rated as ◯.

In order to check the drop impact resistance, the packaging bag was filled with 150 cc of water, sealed, dropped from a height of 1 m, and the presence or absence of abnormalities such as water leakage was confirmed. 0 indicates no abnormality.

The packaging bag was filled with 150 cc of water, sealed, and then heated in a microwave oven (600 W output) for 2 minutes to confirm vapor permeability. The case where there was no smooth steaming, bursting, explosion, etc. was evaluated as ◯.

<Example 2>
A paper having a basis weight of 104.7 g/m ² was used as the paper substrate. As a gas barrier layer, an inorganic deposition film (GL film manufactured by Toppan Printing Co., Ltd.) obtained by depositing aluminum oxide on a polyethylene terephthalate resin film (PET) having a thickness of 12 μm was used. A non-stretched polypropylene resin film (CPP) having a thickness of 50 μm was used as the sealant layer. A PET film having a thickness of 12 μm was used as a base film, and four layers were dry-laminated using a dry-laminating adhesive to obtain a front/back laminate having a layer structure as shown in FIG.

As the bottom material, an inorganic vapor-deposited film (GL film manufactured by Toppan Printing Co., Ltd.) obtained by vapor-depositing aluminum oxide on a polyethylene terephthalate resin film (PET) having a thickness of 12 μm was used as a gas barrier layer. A nylon film having a thickness of 15 μm was used as the base film. A non-stretched polypropylene resin film (CPP) having a thickness of 50 μm was used as the sealant layer. The three layers were dry-laminated using a dry-laminate adhesive to form a bottom material having a layer structure as shown in FIG.

A self-supporting packaging bag as shown in FIG. 1 was produced in the same manner as in Example 1. The weight of paper in the total weight of the packaging bag was 51%, and the weight of plastic was 49%. Evaluation was made in the same manner as in Example 1 below.

<Example 3>
A paper having a basis weight of 104.7 g/m ² was used as the paper substrate. As a gas barrier layer, an inorganic deposition film (GL film manufactured by Toppan Printing Co., Ltd.) obtained by depositing aluminum oxide on a polyethylene terephthalate resin film (PET) having a thickness of 12 μm was used. A non-stretched polypropylene resin film (CPP) having a thickness of 50 μm was used as the sealant layer.

The gas barrier layer and the sealant layer were dry-laminated, and the paper substrate and the gas barrier layer were laminated together by an extrusion lamination method using a polyethylene resin having a thickness of 20 μm to form a front/back laminate having a layer structure as shown in FIG. .

As the bottom material, the same bottom material as used in Example 2 was used, and self-supporting packaging bags similar to those in Examples 1 and 2 were produced. The weight of paper in the total weight of the packaging bag was 51%, and the weight of plastic was 49%. Evaluation was made in the same manner as in Examples 1 and 2 below.

<Comparative Example 1>
A laminate similar to that used in Example 1 was used as the front and back laminates. The same laminate was used which also contained this paper as the substrate. A self-supporting packaging bag was produced in the same manner as in Example 1 except for the above. The weight of paper was 60% of the total weight of the packaging bag, and the weight of plastic was 40%. The following evaluations were made in the same manner.

<Comparative Example 2>
A front and back laminate was produced in the same manner as in Example 1 except that paper with a basis weight of 84 g / m ² was used as the paper base material, and the same bottom material as used in Example 1 was used to have the same self-supporting property. A packaging bag was produced. The weight of paper in the total weight of the packaging bag was 47%, and the weight of plastic was 53%. The following evaluations were made in the same manner.

<Comparative Example 3>
As Comparative Example 3, a configuration in which no paper is used was employed. A self-supporting packaging bag was produced in the same manner as in Example 1, using the bottom material used in Example 1 as the laminate on the front and back surfaces and as the bottom material. The weight of paper in the total weight of the packaging bag was 0%, and the weight of plastic was 100%. The following evaluations were made in the same manner. Table 1 shows the above results.

From the results in Table 1, it can be seen that the self-supporting packaging bags of Examples 1 to 3, which are classified as paper containers, are excellent in bottom-openability, drop impact resistance, and microwave heating aptitude.

Reference Signs List 1 Self-supporting packaging bag 2 Surface laminate 3 Back surface laminate 4 Bottom material 5 Bottom seal portion 6 Side seal portion 7 Top seal portion 10 ...Paper substrate 11...Base film 12...Gas barrier layer 13...Sealant layer 14...Adhesive resin layer 15...Base film 16...Gas barrier layer 17...Sealant Layer 20 Vapor transmission mechanism 21 Vapor release seal portion 22 Unsealed portion 23 Through hole

Claims (5)

The sealant layers of the surface laminate and the back laminate each having a paper substrate, a gas barrier layer, and a sealant layer are opposed to each other, and between them, a bottom material that does not contain paper and has a gas barrier layer and a sealant layer is placed with the sealant layer on the outside. A self-supporting packaging bag obtained by bending the bag 180° and inserting it, and heat-sealing the bottom seal portion and the side seal portion,
The weight of the paper substrate is more than 50% of the total weight of the packaging bag,
the gas barrier layer does not contain a metal foil,
A self-supporting packaging bag, wherein the side seal portion is formed with a vapor passage mechanism including a steam release seal portion that is automatically opened by superheated steam generated during heating in a microwave oven. The vapor passage mechanism has a steam release seal portion projecting from the side seal portion into the packaging bag, and an unsealed portion formed outside the steam release seal portion and communicating with the outside. 2. The self-supporting packaging bag according to claim 1, wherein a through-hole is formed through the surface laminate and the back laminate in the thickness direction. The self-supporting packaging bag according to claim 1 or 2, wherein the basis weight of the paper substrate is 30 g/ ^m2 or more and 200 g/ ^m2 or less. The self-supporting packaging bag according to claim 3, wherein the basis weight of the paper substrate is 50 g/ ^m2 or more and 120 g/ ^m2 or less. The self-supporting packaging bag according to any one of claims 1 to 4, wherein the gas barrier layer is an inorganic deposited film in which a metal oxide deposited layer is formed on a base film.

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