JP2020083431A - Packaging bag - Google Patents

Abstract

To provide a packaging bag which has a metal-based chemical absorbent, and of which embrittlement under high temperature environment is suppressed.SOLUTION: A packaging bag 300 has first and second laminated films 100, 200, the first laminated film 100 has a gas absorption layer 110, which contains a polypropylene resin and a gas absorbent 112, and a first base material layer 120, and the second laminated film 200 has an oxygen absorption layer 210, which contains a thermoplastic resin and an oxygen absorbent 212, and a second base material layer 220. The first and second base material layers 120, 220 have barrier property, the first laminated film 100 and the second laminated film 200 are located so that the gas absorption layer 110 and the oxygen absorption layer 210 face to each other, peripheral edges of the gas absorption layer 110 and the oxygen absorption layer 210, which face to each other, are thermally sealed to each other.SELECTED DRAWING: Figure 1

Description

The present invention relates to a packaging bag.

BACKGROUND ART Conventionally, in the fields of foods, pharmaceuticals, electronic parts, precision machines, recording materials, etc., a method of enclosing a gas absorbent in order to prevent quality deterioration has been adopted. Further, in order to allow the packaging material itself to have a gas absorbing function without putting a separate gas absorbent in the package, the packaging material itself is made to contain the absorbent.

Specifically, as a packaging material that absorbs oxygen, in Patent Document 1, a polyolefin inner surface material, an oxygen absorbing layer made of a composition of polyolefin and an iron-based oxygen absorbent, a polyolefin buffer layer, an aluminum foil, a stretched film or an inorganic material. An oxygen-absorbing packaging material is disclosed in which vapor-deposited plastic films are sequentially laminated.

In addition, as a packaging material that absorbs a sulfide-based gas such as hydrogen sulfide and mercaptan, in Patent Document 2, a first skin layer including an olefin elastomer, and an inorganic adsorbent and a binder that adsorb sulfide are included. A sulfide-based gas adsorption laminate having an adsorption layer is disclosed.

As referred to in Patent Document 2, as an inorganic adsorbent for adsorbing sulfide, a metal-based chemical adsorbent such as copper, iron, zinc, manganese, cobalt, nickel, zirconium, and a lanthanoid element is used. It is known to use a compound or salt containing at least one selected metal.

JP-A-2000-343661 JP, 2016-112510, A

Depending on the application of the packaging material, in addition to gas absorption, heat resistance capable of maintaining the shape for a long period in a high temperature environment may be required. In this case, it is preferable to use a polypropylene resin that is easy to form into a film and has excellent heat resistance. However, when a gas-absorbing film is produced using a polypropylene-based resin and a metal-based chemical absorbent and placed in a high temperature environment, the gas-absorbing film becomes brittle in a short period of time and the heat resistance of polypropylene cannot be fully utilized. The present inventors have found that

Therefore, there is a need to provide a packaging bag which has a metal-based chemical absorbent and whose brittleness is suppressed in a high temperature environment.

As a result of intensive studies, the present inventors have found that the above-mentioned problems can be solved by the following means, and have completed the present invention. That is, the present invention is as follows:
<Aspect 1> Having first and second laminated films,
The first laminated film has a polypropylene resin, and a gas absorbing layer containing a metal chemical absorbent, and a first base material layer,
The second laminated film has a thermoplastic resin, and an oxygen absorbing layer containing an oxygen absorbent, and a second substrate layer,
The first and second base material layers have barrier properties, and the gas absorption layer and the oxygen absorption layer are opposed to each other, the first laminated film and the second laminated film Arranged, and the peripheral edges of the gas absorbing layer and the oxygen absorbing layer facing each other are heat-sealed to each other,
Packaging bag.
<Aspect 2> Aspect 1, wherein the metal-based chemical absorber contains at least one selected from the group consisting of copper, cobalt, manganese, iron, nickel, zinc, silver, calcium, and titanium. Packaging bag.
<Aspect 3> The packaging bag according to Aspect 1 or 2, wherein the thermoplastic resin of the second laminated film is a polypropylene resin.
<Aspect 4> The packaging bag according to any one of Aspects 1 to 3, wherein the first and second base material layers have a barrier layer and a resin layer.
<Aspect 5> A packaging bag containing content, including the content and the packaging bag according to any one of aspects 1 to 4 containing the content.
<Aspect 6> The packaging bag according to Aspect 5, wherein the content is an electronic member.

According to the present invention, it is possible to provide a packaging bag that has a metal-based chemical absorbent and that is less susceptible to embrittlement in a high temperature environment.

FIG. 1 is a side sectional view of the packaging bag of the present invention.

<< packaging bag >>
As shown in FIG. 1, the packaging bag 300 of the present invention is
Having first and second laminated films 100, 200,
The first laminated film 100 has a gas absorbent layer 110 containing a polypropylene resin and a gas absorbent 112, and a first base material layer 120,
The second laminated film 200 has a thermoplastic resin and an oxygen absorption layer 210 containing an oxygen absorbent 212, and a second base material layer 220,
The first laminated film 100 and the second laminated film are formed such that the first and second base material layers 120 and 220 have barrier properties and the gas absorption layer 110 and the oxygen absorption layer 210 face each other. The gas absorbing layer 110 and the oxygen absorbing layer 210 facing each other are heat-sealed with each other.

The first base material layer 120 may include a first barrier layer 122 and a first base material resin layer 124, and the second base material layer 220 may include a second barrier layer 222 and a second barrier layer 222. Of the base resin layer 224.

The present inventors have found that the embrittlement of the film is promoted by placing the polypropylene-based resin and the metal-based chemical absorbent in the presence of oxygen in a high temperature environment in a state of being in contact with each other. Without wishing to be bound by theory, it is believed that this is because the reaction between the oxidizable polypropylene resin and oxygen is promoted by the high temperature environment and the metal chemical absorber acting as a catalyst. Be done. With respect to this problem, the present inventors have found that the above-described configuration can suppress the embrittlement of the film by reducing the oxygen concentration that causes the embrittlement of the polypropylene resin.

Therefore, the gas absorbing film of the present invention has a high temperature, for example, 50°C or higher, 60°C or higher, 70°C or higher, 80°C or higher, or 90°C or higher, and 150°C or lower, 140°C or lower, 130°C or lower, 120°C or lower. Or, it can be used in an environment in which a temperature of 110° C. or lower can be reached. Therefore, the gas absorbing film of the present invention can be used, for example, for packaging all-solid-state lithium-ion batteries.

The packaging bag of the present invention has, for example, a first laminated film and a second laminated film arranged such that the gas absorbing layer and the oxygen absorbing layer face each other, and the gas absorbing layer and the oxygen absorbing layer facing each other. It can be manufactured by heat-sealing the periphery of each other.

Below, each component of this invention is demonstrated.

<First laminated film>
The first laminated film has a gas absorbing layer containing a polypropylene resin and a gas absorbing agent, and a first base material layer. In addition, the first laminated film may have a skin layer on one side or both sides of the gas absorption layer.

The first laminated film can absorb various gases, and can be a hydrogen sulfide absorption film that absorbs hydrogen sulfide particularly well.

The first laminated film can be produced, for example, by melting and kneading the materials constituting each layer of the first laminated film, if necessary, to form a film, and laminating each layer.

The melt-kneading can be performed by using, for example, a kneader, a Henschel mixer, a batch-type kneader such as a mixing roll, or a continuous kneader such as a biaxial kneader.

The film formation can be performed by, for example, an inflation method, a T-die method, a calendar method, a casting method, a hot press molding, an extrusion molding or an injection molding.

The lamination can be performed by an extrusion laminating method such as a sand laminating method, a heat sealing method, a hot press molding, or the like. Moreover, in particular, the lamination of the first base material layer can be performed via an adhesive layer. As the adhesive layer, for example, a dry laminating adhesive, an anchor coat adhesive, a hot melt adhesive, a water-soluble adhesive, an emulsion adhesive, a non-solvent laminating adhesive, and a thermoplastic resin for extrusion laminating can be used. ..

Further, the film formation and the lamination may be simultaneously performed by a coextrusion method such as a coextrusion inflation method and a coextrusion T-die method.

(Gas absorption layer)
The gas absorption layer contains a polypropylene resin and a metal chemical absorbent. The metal-based chemical absorbent may be in contact with the polypropylene-based resin, and particularly may be dispersed in the polypropylene-based resin. The gas absorption layer may be a single layer or a laminated body. Further, in the case of a laminate, the gas absorbing layer may have a layer composed of a polypropylene resin on one or both sides of the layer containing the metal chemical absorbent, In this case, the layer containing the metal-based chemical absorbent may be a layer in which the metal-based chemical absorbent is dispersed in the polyethylene-based resin referred to below.

The content ratio of the metal-based chemical absorbent in the layer containing the metal-based chemical absorbent in the gas absorption layer is 1% by mass based on the mass of the above-mentioned entire layer from the viewpoint of ensuring good absorption capacity. It is preferably 3% by mass or more, 5% by mass or more, 7% by mass or more, or 10% by mass or more, and from the viewpoint of ensuring good film-forming properties, 70% by mass or less, 65% by mass or less, It is preferably 60% by mass or less, 55% by mass or less, or 50% by mass or less.

The thickness of the gas absorption layer is preferably 1 μm or more, 2 μm or more, 3 μm or more, 5 μm or more, 10 μm or more, 20 μm or more, or 30 μm or more from the viewpoint of ensuring good absorption capacity, and 100 μm or less, 90 μm It is preferably not more than 80 μm, from the viewpoint of ensuring the flexibility of the film.

(Gas absorption layer: polypropylene resin)
In the present specification, a polypropylene-based resin is a resin that contains more than 50 mol%, 60 mol% or more, 70 mol% or more, or 80 mol% or more of propylene repeating units in the polymer main chain. Examples of the polypropylene resin include polypropylene (PP) homopolymer, random polypropylene (random PP), block polypropylene (block PP), chlorinated polypropylene, carboxylic acid-modified polypropylene, and derivatives thereof, and mixtures thereof.

(Gas absorption layer: Metal-based chemical absorbent)
The metal-based chemical absorbent may contain at least one selected from the group consisting of copper, cobalt, manganese, iron, nickel, zinc, silver, calcium, and titanium, and particularly these simple substances or compounds, particularly These salts may be, more particularly their silicates.

Particularly preferred metal-based chemical absorbents are metal silicates containing at least one metal selected from copper, zinc, manganese, cobalt and nickel, and more preferably the elemental composition (molar) ratio of metal to silicon is Metal/silicon=0.60 to 0.80. Such an inorganic adsorbent can be produced by reacting a metal salt with an alkali silicate salt. As the metal salt, an inorganic salt of at least one metal selected from copper, zinc, manganese, cobalt, nickel, such as sulfuric acid, hydrochloric acid, nitric acid, and/or an organic salt of formic acid, acetic acid, oxalic acid, etc. is used. be able to. Among these, copper (I), copper (II), and zinc (I) are preferable as the metal. As the above-mentioned silicate, the silicate of the formula of M ₂ O·nSiO ₂ ·xH ₂ O (wherein M represents a monovalent alkali metal, n is 1 or more, and x is 0 or more). Acid alkali salts can be mentioned. The most preferred metal silicate is copper(II) silicate which is a reaction product of copper(II) sulfate and sodium silicate, and is described in, for example, JP 2011-104274 A. For example, a copper (II) silicate-based adsorbent available from Toagosei Co., Ltd. under the name of Kesmon NS-20C can be used. In particular, when this metal-based chemical absorbent is used, hydrogen sulfide can be satisfactorily absorbed as mentioned in Patent Document 2.

(First base material layer)
The first base material layer is a layer having a barrier property. The first base material layer may include a first barrier layer and a first base material resin layer.

The lamination of the first base material layer and the gas absorption layer and the lamination of the following layers that can form the first base material layer can be performed, for example, via an adhesive layer. As the adhesive layer, for example, a dry laminating adhesive, an anchor coat adhesive, a hot melt adhesive, a water-soluble adhesive, an emulsion adhesive, a non-solvent laminating adhesive, a thermoplastic resin for extrusion laminating and the like can be used. ..

(First base material layer: first barrier layer)
As the first barrier layer, a material that can suppress permeation of moisture, organic gas and inorganic gas from the outside into the functional layer can be used. Examples of the barrier layer include, but are not limited to, aluminum foil, metal foil such as aluminum alloy, aluminum vapor deposition film, silica vapor deposition film, alumina vapor deposition film, and inorganic vapor deposition film such as silica/alumina binary vapor deposition film. Alternatively, an organic coating film such as a polyvinylidene chloride coating film or a polyvinylidene fluoride coating film can be used. In particular, it is preferable to use an aluminum foil as the first barrier layer from the viewpoint of easily achieving both the barrier property and the handleability.

The thickness of the first barrier layer is preferably 7 μm or more, 10 μm or more, or 15 μm or more from the viewpoint of ensuring strength and barrier properties, and is 45 μm or less, 40 μm or less, or 35 μm or less, It is preferable from the viewpoint of improving handleability.

(First base material layer: first base material resin layer)
As the first base resin layer, a thermoplastic resin having excellent impact resistance, abrasion resistance, etc., such as polyolefin, vinyl-based polymer, polyester, polyamide, etc., may be used alone or in a combination of two or more layers. Can be used. This base resin layer may be a stretched film or a non-stretched film. The base resin layer may be present on one side or both sides of the barrier layer. This base resin layer can protect the barrier layer.

Examples of the polyolefin include polyethylene resin and polypropylene resin.

In the present specification, the polyethylene-based resin is a resin containing a repeating unit of an ethylene group in the main chain of the polymer in an amount of more than 50 mol%, 60 mol% or more, 70 mol% or more, or 80 mol% or more. As such polyethylene resin, polyethylene such as low density polyethylene (LDPE), linear low density polyethylene (LLDPE), medium density polyethylene (MDPE), high density polyethylene (HDPE) may be used. A copolymer with an ethylene-based monomer having a group or an ester group may be used.

As the polypropylene-based resin, the polypropylene-based resins mentioned for the gas absorption layer can be used.

Examples of the vinyl polymer include polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), polychlorotrifluoroethylene, polytetrafluoroethylene, polyacrylonitrile (PAN) and the like.

Examples of polyesters include polyethylene terephthalate (PET) and polybutylene terephthalate.

Examples of the polyamide include nylon such as nylon (registered trademark) 6 and nylon MXD6.

The thickness of the base resin layer is preferably 7 μm or more, 10 μm or more, or 15 μm or more from the viewpoint of satisfactorily protecting the barrier layer, and is 55 μm or less, 50 μm or less, or 45 μm or less. It is preferable from the viewpoint of improving the property.

(Skin layer)
The skin layer may be a layer present on one side or both sides of the gas absorption layer. Further, the skin layer may be fused to the gas absorption layer.

The skin layer can prevent the metallic chemical absorbent from coming off and coming into contact with the contents. Further, the skin layer may be a layer containing no metal-based chemical absorbent.

The skin layer may be composed of polyolefin, for example. As the polyolefin, the polyolefins mentioned for the first base resin layer can be used.

The thickness of the skin layer can be 1 μm or more, 3 μm or more, 5 μm or more, or 7 μm or more, and can be 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, or 15 μm or less.

<Second laminated film>
The second laminated film has a thermoplastic resin, an oxygen absorbing layer containing an oxygen absorbent dispersed in the thermoplastic resin, and a second base material layer. In addition, the first laminated film may have a skin layer on one side or both sides of the gas absorption layer.

(Oxygen absorption layer)
The oxygen absorption layer contains a thermoplastic resin and an oxygen absorbent. The oxygen absorber may be dispersed in the thermoplastic resin.

In the oxygen-absorbing layer, the thermoplastic resin is preferably contained in an amount of 50% by mass or more, 60% by mass or more, 70% by mass or more, or 75% by mass or more, and 98% by mass or less, 95% by mass with respect to the entire oxygen absorption layer. Below, 90 mass% or less, 89.7 mass% or less, or 85 mass% or less is contained.

The thickness of the oxygen absorption layer can be 10 μm or more, 20 μm or more, or 30 μm or more, and can be 300 μm or less, 200 μm or less, 100 μm or less, 80 μm or less, or 50 μm or less.

The oxygen absorption layer can be produced, for example, by melt-kneading the material forming the gas absorption layer and forming a film from this. Melt kneading and film formation can be performed, for example, by the method described for the gas absorption layer.

(Oxygen absorbing layer: thermoplastic resin)
As the thermoplastic resin of the oxygen absorption layer, for example, polyolefin can be used. As the polyolefin, for example, the polyolefins mentioned for the base resin layer can be used.

(Oxygen absorbing layer: oxygen absorbing agent)
Examples of the oxygen absorber include metal oxides having oxygen deficiency, inorganic oxygen absorbers such as iron-based oxygen absorbers, and oxygen-absorbing metal-containing resin compositions containing metals and polyphenols. Be done.

Examples of the metal oxide having an oxygen deficiency include cerium oxide having an oxygen deficiency and titanium dioxide having a metal deficiency. Among them, cerium oxide having oxygen deficiency as an absorbent is preferable from the viewpoint of oxygen absorption.

The metal oxide having oxygen deficiency will be described more specifically. Oxygen deficiency of the metal oxide (MO ₂ ) is forcibly withdrawn from the crystal lattice of the metal oxide by the reduction treatment in a strong reducing atmosphere, as represented by the following formula (1). It is brought about by the oxygen deficiency state (MO _2-x , 0<x<2). The reduction treatment can be performed, for example, by heat treatment at a high temperature such as 1000° C. in a reducing atmosphere such as hydrogen gas.
MO ₂ +xH ₂ →MO _2-x +xH ₂ O (1)

Then, as shown in the following formula (2), the oxygen-deficient portion reacts with oxygen, so that the effect as an inorganic oxygen absorber is exhibited.
MO _2−x +(x/2)O ₂ →MO ₂ ...(2)

The value of x may be a positive number of 1.0 or less, and is preferably a positive number of 0.7 or less. As shown in equation (2) above, the metal oxide need not have water present in the atmosphere in the reaction with oxygen. Therefore, the use of a metal oxide having an oxygen deficiency as the inorganic oxygen absorber is particularly effective for contents that do not like water.

As the iron-based oxygen absorber, for example, iron powder (eg, reduced iron powder, atomized iron powder, activated iron powder, etc.), ferrous oxide, ferrous salt, etc. can be used.

(Second base material layer)
The second base material layer is a layer having a barrier layer. The second base material layer may include a second barrier layer and a second base material resin layer. As the second barrier layer and the second base resin layer, for example, the materials mentioned for the first barrier layer and the first base resin layer can be used.

The lamination of the second base material layer and the oxygen absorbing layer, and the lamination of the following layers that can form the second base material layer can be performed via an adhesive layer, for example. As the adhesive layer, those mentioned for the first base material layer can be used.
(Skin layer)
The skin layer may be a layer existing on one side or both sides of the oxygen absorbing layer. Further, the skin layer may be fused to the oxygen absorbing layer.

The skin layer can prevent the oxygen absorbent from coming off and coming into contact with the contents. Further, the skin layer may be a layer containing no oxygen absorbent.

The skin layer may be composed of polyolefin, for example. As the polyolefin, for example, the polyolefins mentioned for the first base resin layer can be used.

The thickness of the skin layer can be 1 μm or more, 3 μm or more, 5 μm or more, or 7 μm or more, and can be 50 μm or less, 40 μm or less, 30 μm or less, 20 μm or less, or 15 μm or less.

<<Packaging bag with contents>>
The packaging bag of the present invention includes the contents and the above-mentioned packaging bag containing the contents.

<Contents>
The contents are not limited as long as they can be deteriorated by contact with the outside air, and include drugs, foods, cosmetics, medical instruments, medical devices, electronic members, precision machines, recording materials, etc. You can In addition to pharmaceutical preparations, the drugs include detergents, agricultural chemicals and the like.

Among them, when the content is an electronic member, particularly an all-solid-state lithium-ion battery using a sulfide-based solid electrolyte, heat resistance capable of withstanding heat generation during use, and hydrogen sulfide generated by the sulfide-based solid electrolyte Therefore, the packaging bag of the present invention becomes more useful.

The present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

<<Preparation of sample>>
<Film of sample 1>
90 parts by mass of polypropylene (Novatech FL02A, Nippon Polypro Co., Ltd.) as a thermoplastic resin, and 10 parts by mass of a copper(II) silicate-based adsorbent (Kesmon NS-20C, Toagosei Co., Ltd.) as a gas absorbent. Was mixed with a Banbury mixer at 190° C. for 10 minutes, cut into a predetermined mass, and hot-press molded (press temperature 190° C., pressure 40 MPa, press time 2 minutes) to give Sample 1 having a thickness of 100 μm. The film of was produced.

<Film of sample 2>
A film of Sample 2 having a thickness of 100 μm was prepared in the same manner as Sample 1 except that another polypropylene (Novatech FG3DC, Japan Polypro Co., Ltd.) was used as the thermoplastic resin.

<Oxygen absorption film>
Using a Banbury mixer, 25 parts by mass of polypropylene (Novatech FG3DC, Nippon Polypro Co., Ltd.) as a thermoplastic resin and 75 parts by mass of cerium oxide CeO _2-x (x=0.5) having an oxygen deficiency as an oxygen absorbent are used. By kneading at 190°C for 10 minutes to prepare a masterbatch for oxygen absorption layer, cutting this into a predetermined mass, and hot press molding (pressing temperature 190°C, pressure 40 MPa, pressing time 2 minutes) An oxygen absorbing film having a thickness of 100 μm was produced.

<<Evaluation>>
<Evaluation as a film>
The produced film of Sample 1 was cut into 5 cm square pieces and individually enclosed in a glass container having a volume of 22 ml (Comparative Example 1). The same operation was performed on the film of Sample 2 (Comparative Example 2).

Further, the film of Sample 1 and the oxygen absorbing film were each cut into 5 cm square pieces, and both were enclosed in a glass container having a volume of 22 ml (Example 1).

The glass container in which each film was enclosed was left for a time sufficient for the oxygen absorbing film to absorb oxygen in the container, and then this container was placed in an oven at 100° C. and stored for 5 days.

After storage, the sample films in the containers of Example 1 and Comparative Examples 1 and 2 were taken out, and the cracks on the surface when the films were bent 180° were visually observed. The evaluation criteria are as follows.
A: No cracks and cracks were generated B: Cracks were generated C: Cracks were generated

<Evaluation as a laminate for packaging>
An aluminum foil having a thickness of 9 μm as a barrier layer was adhered to one side of each film of Sample 1 and Sample 2 produced, and 12 μm of polyethylene terephthalate (PET) having a thickness of 12 μm as a base resin layer was adhered thereto. Then, the packaging laminate 1 and the packaging laminate 2 as the first laminated film were produced. Adhesion is performed by mixing Takelac A525S (Mitsui Chemicals, Inc.), Takenate A52 (Mitsui Chemicals, Inc.), and ethyl acetate in a predetermined composition, applying a coating amount of 3 g/m ² with a hand coater, and press-bonding. It was done by doing.

Further, a barrier layer and a base resin layer were adhered to one side of the produced oxygen absorbing film in the same manner as above to produce an oxygen absorbing packaging laminate as a second laminated film.

The same test as described above was performed using Comparative Example 1 in which the produced packaging laminate 1 was cut into a 5 mm square and individually enclosed in a glass container having a volume of 22 ml. The same operation was performed on the packaging laminate 2 (Comparative Example 2).

Further, the same test as above was carried out with Example 1 in which the packaging laminate 1 and the oxygen-absorbing packaging laminate were each cut into 5 cm square pieces and sealed in a glass container having a volume of 22 ml.

Table 1 shows the configurations and evaluation results of Examples and Comparative Examples.

From Table 1, in Comparative Examples 1 and 2 which are modes having no oxygen absorber, cracks or cracks were generated, whereas in Example 1 which is a mode having oxygen absorbers, cracks and cracks were generated. You can understand that not.

100 First Laminated Film 110 Gas Absorption Layer 112 Gas Absorber 120 First Base Material Layer 122 First Barrier Layer 124 First Base Material Resin Layer 200 Second Laminated Film 210 Oxygen Absorption Layer 212 Oxygen Absorber 220 First base material layer 222 Second barrier layer 224 Second base material resin layer 300 Packaging bag

Claims (6)

Having a first and a second laminated film,
The first laminated film has a polypropylene resin, and a gas absorbing layer containing a metal chemical absorbent, and a first base material layer,
The second laminated film has a thermoplastic resin, and an oxygen absorbing layer containing an oxygen absorbent, and a second substrate layer,
The first and second base material layers have barrier properties, and the gas absorption layer and the oxygen absorption layer are opposed to each other, the first laminated film and the second laminated film Arranged, and the peripheral edges of the gas absorbing layer and the oxygen absorbing layer facing each other are heat-sealed to each other,
Packaging bag. The packaging bag according to claim 1, wherein the metal-based chemical absorbent contains at least one selected from the group consisting of copper, cobalt, manganese, iron, nickel, zinc, silver, calcium, and titanium. .. The packaging bag according to claim 1, wherein the thermoplastic resin of the second laminated film is a polypropylene resin. The packaging bag according to claim 1, wherein the first and second base material layers have a barrier layer and a resin layer. A packaging bag containing contents, including the contents and the packaging bag according to any one of claims 1 to 4, which stores the contents. The packaging bag according to claim 5, wherein the content is an electronic member.

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