JPH0615228B2 - Packaging material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a packaging material suitable for packaging relatively heavy items, such as movie roll films, among various photographic light-sensitive materials, light-sensitive substances, electronic parts and the like. It is about.

[Conventional technology]

In general, as a packaging material for high-tech products such as photographic light-sensitive materials, in addition to completely blocking light, gas barrier properties, moisture resistance, physical strength (breaking strength, tear strength, impact drilling strength, gelbotest strength, abrasion strength) Etc.), heat sealing suitability (heat sealing strength, cut sealing property, hot tack property, foreign substance sealing property, etc.), antistatic property, lubricity, low dust generation property, flatness, etc. To be done.
It is extremely difficult to combine these properties with a single film material, and conventionally, a packaging material having a plurality of layers has been used.

The present inventor has diligently studied in order to improve a packaging material for a photosensitive substance, and has already disclosed what has improved physical strength by combining two layers of uniaxially stretched film (JP-A-57-6754). ing.

Further, in a three-layer laminated film obtained by laminating a uniaxial molecular orientation thermoplastic resin film on both sides of a sheet-shaped foam, the thickness of the sheet-shaped foam is 0.3 to 2.0 mm, and the expansion ratio is 5 to 50. The double-layered uniaxial molecular orientation film is the thickness of the laminated film that is heat-melt-bonded on both sides of the foam with or without the heat-melting adhesive layer so that the molecular orientation axes intersect at an angle of 30 degrees or more. Is a laminated film that has excellent impact hole ake strength and gelbotest strength compressed to a thickness of 40 to 85% of the theoretical sum of each layer (residual thickness ratio), and has a small curl. Has already been disclosed (Japanese Patent Laid-Open No. 59-201848).

[Problems to be solved by the invention]

In the packaging material composed of such a plurality of layers, since each film layer is laminated with an adhesive layer or laminated by coextrusion, each layer is completely integrated and adhered to be hard,
The physical strength was low and the curl was large.

Further, when a co-extruded T-die film, inflation film or the like is laminated into a laminated film having a plurality of constitutions using an adhesive layer, trimming loss is large and uneconomical.

An object of the present invention is to solve the above problems and to provide a packaging material which is flexible, has a large physical strength, and has a small curl.

[Means for solving problems]

In order to achieve the above-mentioned object, the present invention is configured so that pseudo-adhesion is achieved by blocking, which is conventionally regarded as a failure, without using an adhesive layer, and in particular, an ethylene acrylate ester-based resin layer having a predetermined composition is a physical layer. The inventors have completed the present invention by finding that the strength is high and the occurrence of blocking is large.

More specifically, an ethylene acrylate resin film layer containing 50 wt% or more of an ethylene acrylate resin having a methyl acrylate and / or ethyl acrylate content of 7 wt% or more and 0.01 to 2.00 wt% of an antioxidant, and a light-shielding film. Of two ethylene co-extruded films having a thermoplastic resin film layer having a slip angle of 6 to 30 and containing at least 10% by weight of an organic substance, a lubricant and an ethylene copolymer resin, It is characterized in that the layers are pseudo-bonded by blocking.

A typical packaging material of the present invention has two layers of ethylene acrylate resin film in which an inner layer of a multi-layer coextrusion blown film is pseudo-bonded by blocking. This ethylene acrylic acid ester resin film layer is not completely bonded and fixed as if it is bonded by an adhesive layer, but is pseudo-bonded in a somewhat flexible state by blocking without using an adhesive at all and physically. Improves strength and prevents curling. In some cases, it may be pseudo-bonded in the state of having voids, and in this case, a buffering effect is also obtained, which is preferable.

This ethylene acrylic ester resin film layer,
Contains 50% by weight or more of ethylene acrylate resin. Ethylene acrylate resin content is 50% by weight
When it is less than the above range, flexibility is poor, blocking is less likely to occur, wrinkles and streaks are likely to occur, and the antistatic effect and physical strength are also reduced.

The ethylene acrylate resin contains 7% by weight or more of methyl acrylate and / or ethyl acrylate. When the content is less than 7% by weight, blocking is less likely to occur, flexibility is poor, wrinkles and streaks are likely to occur, physical strength is low, and antistatic effect is not exerted.

The ethylene acrylate resin film layer contains 0.01 to 2.00% by weight of an antioxidant. If the amount of the antioxidant is less than 0.01% by weight, the antioxidant effect of the resin becomes small, and the lump of the antioxidant is often generated due to burning of the resin, resulting in poor appearance. In addition, the generation of the spots also causes the generation of pressure fog when the photographic light-sensitive material is packaged.

On the other hand, if it exceeds 2.00% by weight, not only the photographic light-sensitive material utilizing the oxidation / reduction effect is adversely affected, but also bleed-out occurs with the passage of time and the appearance is deteriorated.

Typical examples of the antioxidant are shown below, but the antioxidant is not limited thereto.

Phenol-based n-octadecyl-3 (3 ', 5'-di-t-butyl 4'
Hydroxyphenyl) propinate, 2,6 di-t-butyl 4-methylphenol, 2,6 di-t-butyl-p-cresol, 2,2'-methylenebis (4-methyl-6-t-butylphenol), 4 4,4'-thiobis (3-methyl6-t-butylphenol), 4,4'-butylidenebis (3-methyl-6-t-butylphenol), stearyl-β (3'5-di-4-butyl-4-) Hydroxyphenyl) propionate, 1,1,3, -tris (2-methyl-4-hydroxyphenyl) butane, 1,3,5, trimethyl-2,4,6-tris (3,5-di-t-butyl) -4-hydroxybenzyl) benzene, octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, tetrakis [methylene-3 (3 ', 5'-di-t-butyl-4'] -Hydroxyphenyl) Ropionate] methane, etc.Sulfur-based dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, laurylstearyl thiodipropionate, distearyl-3 ', 3-thiodipropionate, Ditridecyl-3'-, thiodipropionate, etc. Phosphorus-based trinonylphenyl phosphite, triphenyl phosphite, etc. Especially 2,6-di-t-butyl-p-cresol (BHT) and low volatility high molecular weight phenol type Antioxidant (trade name: lregan
ox 1010, lreganox330, To pano ICA, etc.), dilauryl thiodipropionate, distearyl thiopropionate, dialkyl phosphate and the like, and it is effective to use one or more, especially two or more thereof in combination.

In order to pseudo-adhere this ethylene acrylic acid ester resin film layer by blocking, for example, when forming a multi-layer coextrusion inflation film by a multi-layer coextrusion inflation method, it was newly provided in the subsequent stage of the take-up nip roll or the take-up nip roll. This is performed by pressing the ethylene acrylic acid ester-based resin film layer with a pressure roll. Round die method The round die (ring die) used in the multi-layer coextrusion blown film molding machine is roughly classified into three methods: an in-die lamination method, an outside die lamination method, and a laminar flow supply method. Is preferable because of its high interlayer adhesion.

Also, in the case of a laminated film in which the ethylene acrylic acid ester resin film layer of the inner layer of the multi-layer coextrusion inflation film is pseudo-bonded by blocking, there is no ear loss like the film laminated with the conventional adhesive layer, and blocking occurs simultaneously with the inflation film molding. Since the laminated film can be manufactured, the film can be effectively used and is stable, and wrinkles, melt fracture, etc. hardly occur, and the film formability is good.

A thermoplastic resin film layer having a predetermined composition is laminated on the outside of the ethylene acrylate resin film layer by a coextrusion inflation film molding method directly or via an intermediate layer.

The thermoplastic resin film layer contains 10% by weight or more of a light-shielding substance, a lubricant and an ethylene copolymer resin, and has a sliding angle of 6 to 30 degrees.

The light-shielding substance is a substance that can be kneaded or dispersed in each layer and does not transmit visible light, infrared light, ultraviolet light, or the like. Examples of the light-shielding substance that can be used in the present invention include various carbon blacks, graphite, iron oxide, zinc oxide, titanium oxide, clay, aluminum powder, aluminum paste, calcium carbonate, mica, barium sulfate, talc,
Examples thereof include cadmium pigments, red iron oxide, cobalt blue, copper phthalocyanine pigments, monoazo or polyazo pigments, organic pigments such as aniline black, inorganic pigments and coloring dyes.

Among these light-shielding substances, in terms of quality, cost, light-shielding ability, etc., it is lower than coloring pigments that easily absorb or reflect light, in particular, various carbon blacks of black pigments, graphite, and silver-colored aluminum powder and aluminum paste. Those from which volatile substances have been removed are preferred.

As a method of blending these light-shielding substances into each layer, there are a master bee coloring method, a compound coloring method and the like, which have been often performed conventionally. The light-shielding substance is a powder colorant, a paste colorant, a wet colorant, a masterbatch, a dye / pigment, as a usage pattern depending on the resin used, the machine used, the cost, etc.
There are colored pellets, etc. Various photosensitive materials, particularly when used as a packaging material for various photographic photosensitive materials, from the viewpoint of securing light-shielding properties, improving cost and physical strength, a furnace carbon black having an average particle size of 200 mμ or less is preferable and expensive. As the light-shielding substance having an antistatic effect, acetylene carbon black, Ketjen carbon black, graphite and the like are preferable. It is also preferable to mix two or more light-shielding substances according to the required characteristics, if necessary. The average particle size even if it is preferred to include the following light-shielding material 200mμ to ² to 50 g / m ² laminated film of 0.5 g / m. On the other hand, among these carbon blacks
A furnace carbon black having a pH of 5 to 9 and an average particle size of 10 to 120 mμ is preferable, and a furnace carbon black having a pH of 6 to 9 and an average particle size of 50 mμ or less is particularly preferable. By using one with such a pH and particle size, fogging is less likely to occur, the increase or decrease in photosensitivity is less, the light-shielding ability is large, and pinholes due to carbon black lumps (fish) or fish eyes are generated. It is possible to obtain a packaging material having various advantages such as improved physical strength that is difficult to improve and improved heat sealability.

Although there are various forms of blending the light-shielding substance in each layer as described above, the masterbatch method is preferable in terms of cost, prevention of contamination of the workplace, and the like.

Next to the carbon black, a metal powder that is preferable as a light-shielding substance will be described. This metal powder is a light-reflecting light-shielding substance that gives it a silver-colored, highly commercialized appearance, and is excellent in many points such as moisture resistance, light-shielding property, antistatic property, heat resistance under sunlight, and gas barrier property. There is.

As the metal powder, a substance obtained by removing a low volatile substance from aluminum powder or aluminum paste and kneading with a thermoplastic resin is particularly preferable.

Here, the aluminum paste is a paste in the presence of mineral spirits and a small amount of higher fatty acids such as stearic acid or oleic acid when producing aluminum powder by a known method such as a ball mill method, a stamp method or an atomizing method. It was made in. In the present invention, this aluminum paste and polyolefin thermoplastic resin (various polypropylene resin, various polyethylene resin, EVA resin, E
Aluminum paste compound resin, aluminum paste master that is obtained by heating and kneading EA resin, EAA resin, etc.) and other thermoplastic resins to remove low volatile substances (mineral spirits with a strong malodor) and / or removing them with a vacuum pump. It is preferably used as a batch resin.

In addition to aluminum powder, in addition to powdered molten aluminum by atomizing method, granulating method, rotary disc dropping method, evaporation method, etc., aluminum foil is crushed by ball mill method, stamp mill method or the like into flakes. Including things. Since the aluminum powder alone is unstable, various known treatments such as coating the surface of the aluminum powder with a higher fatty acid to render it inactive are performed.

Instead of the light-shielding substance or in combination with the light-shielding substance, silica, diatomaceous earth, talc, calcium silicate,
Aluminum silicate, magnesium silicate, calcium carbonate, higher fatty acid polyvinyl ester, n-octadecyl urea, dicarboxylic acid ester amide, N, N'-dioleyl oxamide and the like may be added to prevent blocking of the outer layer.

The representative types of the lubricants and their manufacturer names are described below, but the present invention is not limited to these.

(1) Silicone-based lubricants; various grades of dimethylpolysiloxane (Shin-Etsu Silicone, Toray Silicone), etc. (2) Oleic acid amide-based lubricants: Armoslip CP (Lion Akzo), Neutron (Nippon Seika), Neutron E -18 (Nippon Seika), Amide O (Nitto Kagaku),
Alflo E-10 (Nippon Yushi), Diamond O-200
(Nippon Kasei), Diamid G-200 (Nippon Kasei), etc. (3) Elucic acid amide lubricants; Alfuro-P-10 (Nippon Yushi), Neutron S (Nippon Seika), etc. (4) Stearic acid amide Lubricants: Alfro-S-10 (Nippon Yushi), Neutron 2 (Nippon Seika), Diamond
200 (Nippon Kasei), etc. (5) Bis fatty acid amide lubricants; Bisamide (Nippon Kasei), Diamid 200 bis (Nippon Kasei), Armowax EBS (Lion Akzo), etc. (6) Alkylamine lubricants; Electrostripper TS
-2 (Kao soap) etc.

When used for packaging photographic light-sensitive materials, the amount of these lubricants that do not adversely affect the photographic light-sensitive material is 0.01 to 1.0% by weight.
Therefore, not only the single addition but also two types may be used in combination.
The fatty acid amide-based lubricant preferred in the present invention has 8 to 50 carbon atoms.
And particularly preferably 15 to 35.

Ethylene copolymer resin contained in the thermoplastic resin film layer, ethylene-propylene copolymer resin, L-LDPE resin, EEA resin, EMA resin, EVA resin, EAA resin can be used, 10 wt% or more include. If it is less than 10% by weight, the delamination strength is small and the physical strength is greatly reduced when a large amount of the light-shielding substance and the lubricant are contained.

In addition, the thermoplastic resin film layer has a sliding angle of 6 to 30 degrees in order to improve sliding during blown film molding, lamination with other film layers, bag making, product packaging, etc., and to prevent wrinkles. It has become.

The sliding angle is the angle from the horizontal plane at which the contact surface of the film layer starts to slide when the film layer is attached to a solid substance, and is measured by the test method described later.

If the slip angle is less than 9 degrees, slipping occurs when winding the laminated film, and winding deviation occurs, which is not practical. Also, a package using such a laminated film cannot be stacked.

On the other hand, if the slip angle exceeds 30 degrees, wrinkles and streaks are generated during film formation, and troubles occur in the process of packaging using such a laminated film, which is not practical.

In addition, the thermoplastic resin film layer has a softening point (ASTM
It is preferred that D1525) is high. This is because when the sealed / light-shielding bag is manufactured by using the packaging material of the present invention by the heat-sealing method or the like, it is necessary to completely melt and bond the blocking layer in the heat-sealed portion.

The multilayer coextrusion blown film has an ethylene acrylic acid ester resin film layer and a thermoplastic resin film layer, and an intermediate layer may be laminated between them.

The packaging material of the present invention can be used for packaging various products, and is particularly suitable for packaging photosensitive materials such as photographic light-sensitive materials, foods, pharmaceuticals, and chemical substances.

In particular, when using a multi-layer coextrusion film containing a light-shielding substance, the quality is destroyed by slight gas, light and humidity, silver halide photographic light-sensitive materials, diazo photographic light-sensitive materials, direct positive color light-sensitive materials, photosensitive resins, It is suitable as a photographic light-sensitive material such as a development-type photographic light-sensitive material, a diffusion transfer type photographic light-sensitive material, and a photosensitive heat-sensitive material.

When the packaging material of the present invention is applied to, for example, the above-mentioned photographic light-sensitive material, a single flat bag, a double flat bag, a self-supporting bag, a single gusset bag, a double gusset bag, a laminated film, and a moisture-proof box inside,
It can be used in all known forms such as inside a light-room loading light-shielding magazine and leader paper.

The bag-making method is a conventionally known plastic film sealing method such as heat sealing, fusing sealing, impulse sealing, ultrasonic sealing, or high-frequency sealing depending on the properties of the laminated film used. Note that it is also possible to make a bag using an appropriate adhesive or pressure-sensitive adhesive.

[Action]

In the packaging material of the present invention, the ethylene acrylic acid ester-based resin film layers located inside are pseudo-adhered to each other by blocking, so that the ethylene acrylic acid ester-based resin film layers are not completely integrated and fixed, Pseudo-adhesion with elasticity to some voids, and in some cases, pseudo-adhesion with voids, improves tear strength and reduces curl. In addition, the thermoplastic resin film layer blocks the bad odor of the ethylene acrylic ester resin film layer and prevents it from appearing outside.

〔Example〕

Examples of the packaging material according to the present invention will be described below with reference to FIGS.
It will be described with reference to the drawings.

1 to 7 are partial cross-sectional views showing the layer structure of a typical packaging material of the present invention.

Fig. 1 shows that the packaging material consists of four layers, an ethylene acrylic acid ester-based resin film layer 1.1 which is an inner layer of a multi-layer coextrusion inflation film and a thermoplastic resin film layer 2.2 which is an outer layer of the same film. Ester-based resin film layer 1 and thermoplastic resin film layer 2
Is a two-layer coextrusion film 3 formed by a circular die two-layer coextrusion inflation film molding machine. Further, a pseudo adhesive layer adhered by blocking is provided between the ethylene acrylic ester resin film layers 1 and 1 which are the inner layers.

The packaging material of FIG. 2 is the same as the packaging material of FIG. 1 except that the thermoplastic resin film layer 2a containing a light-shielding substance is used as the outer layer of the multilayer coextrusion inflation film 3a having a light-shielding property.

The packaging material of FIG. 3 is the same as the packaging material of FIG. 1 except that the thermoplastic resin film layer 2a having a light-shielding property and the ethylene acrylate resin film layer 1a are used.

The packaging material of FIG. 4 is the same as the packaging material of FIG. 1 except that the ethylene acrylate resin film layer 1a having a light shielding property is used.

The packaging material of FIG. 5 is composed of 6 layers including an ethylene acrylate resin film layer 1.1 which is an inner layer of a multi-layer coextrusion inflation film, an intermediate layer 4.4 and a thermoplastic resin film layer 2 which is an outer layer 2. Thus, the ethylene acrylic acid ester-based resin film layer 1, the intermediate layer 4, and the thermoplastic resin film layer 2 are the three-layer coextrusion film 5 formed by the round die method three-layer coextrusion inflation film forming method. A pseudo adhesive layer is formed between the ethylene acrylic acid ester resin film layers 1 and 1 by blocking.

In the packaging material of FIG. 6, except that each layer has a light-shielding property,
It is the same as the packaging material of FIG.

The packaging material of FIG. 7 is an ethylene acrylic ester resin layer 1.1, an intermediate layer 41, 41 which is an inner layer in a multi-layer coextrusion blown film, and an intermediate layer 42 having a light shielding property.
a ・ 42a and a thermoplastic resin film layer 2a having a light-shielding property which is an outer layer in a multilayer coextrusion blown film
2a, these ethylene acrylic acid ester-based resin film layer 1, intermediate layers 41 and 42a, and thermoplastic resin film layer 2a are four-layer coextruded film formed by a round die method four-layer coextrusion inflation film molding method. 6a. A pseudo adhesive layer is formed between the ethylene acrylic acid ester resin film layers 1 and 1 by blocking.

Next, experimental results comparing the characteristics of the products I to V of the present invention and the comparative product I will be described.

Inventive Product I Inventive Product I corresponds to the layer structure of FIG.

The ethylene acrylic acid ester-based resin film layer 1 has a comonomer content of 18% by weight, MI of 6 g / 10 minutes, and density of 0.9.
EEA resin 70% by weight with Vicat softening point 56 ° C, ethylene copolymer resin of ethylene and octene-1 with 3g / 10min, density 0.920g / cm ³ , MI 2g / 10min, Vicat softening point Is composed of 30% by weight of L-LDPE resin at 96 ° C and has a thickness of 25 μm.

The thermoplastic resin film layer 2a, density and 0.954a / cm ^3, MI
HDPE resin with 1.1g / 10min, Vicat softening point of 126 ℃ 20% by weight
Is a copolymer resin of ethylene and 4-methylpentene-1, having a density of 0.920 g / cm ³ , MI of 2.1 g / 10 minutes, a Vicat softening point of 100 ° C., L-LDPE resin of 76.95% by weight, carbon It is composed of 3% by weight of black and 0.05% by weight of oleic acid amide, and has a thickness of 25 μm and a sliding angle of 9 to 30 °.

Inventive product II The inventive product II corresponds to the layer structure shown in FIG.

The ethylene acrylate resin film layer 1a has a comonomer content of 15% by weight, an MI of 1.5 g / 10 minutes, a density of 0.93 g / 10 minutes, an EEA resin with a Vicat softening point of 61 ° C. 60% by weight and ethylene. And an ethylene copolymer resin of butene-1, having a density of 0.890 g / cm ³ , an MI of 1 g / 10 minutes, a Vicat softening point of 58 ° C., 38% by weight of L-LDPE resin, and 2% by weight of carbon black. And has a thickness of 25 μm.

The thermoplastic resin film layer 2a is the same as the product I of the present invention.

Invention product III Invention product III also corresponds to the layer structure of FIG.

The ethylene acrylate resin film layer 1a has a comonomer content of 20% by weight, MI of 20 g / 10 minutes, and a density of 0.
93 g / 10 min, an ethylene copolymer resin Vicat softening point 50 ° C. of EEA resin 60 wt% of ethylene and butene-1, density of 0.906 g / cm ^3, MI is 0.8 g / 10 min, Vicat softening It is composed of 37% by weight of L-LDPE resin having a point of 84 ° C. and 3% by weight of carbon black, and has a thickness of 25 μm.

The thermoplastic resin film layer 2a is the same as the product I of the present invention.

Inventive product IV Inventive product IV also corresponds to the layer structure shown in FIG.

The ethylene acrylic acid ester-based resin film layer 1a has the same resin composition as the product II of the present invention and is formed to a thickness of 30 μm.

The thermoplastic resin film layer 2a has a density of 0.923 g / cm ³ and an MI of
2.4g / 10min, 5% by weight of LDPE resin with Vicat softening point of 92 ℃
And 92% by weight of HDPE resin having a density of 0.964 g / cm ³ , MI of 0.4 g / 10 min, Vicat softening point of 128 ° C., and carbon black 3
It has a thickness of 20 μm and a sliding angle of 9 degrees.

Inventive product V Inventive product V also corresponds to the layer structure shown in FIG.

The ethylene acrylate resin film layer 1a has a comonomer content of 20% by weight, MI of 20 g / 10 minutes, and a density of 0.
93 g / 10 min, Vicat softening point is 50% EEA resin 60 wt% and ethylene and ethylene copolymer resin of 4-methylpentene-1, density is 0.920 g / cm ³ , MI is 2.1 g / 10 min. ,
It is composed of 38% by weight of L-LDPE resin having a Vicat softening point of 100 ° C. and 2% by weight of carbon black and has a thickness of 25 μm.

The thermoplastic resin film layer 2a is the same as the product III of the invention.

Comparative product I A layer formed with the same resin composition as the ethylene acrylic acid ester-based resin film layer of Invention product IV and having a thickness of 50 1/3, and a thermoplastic resin film layer of the Invention product IV having the same resin composition. It is a packaging material for a two-layer coextruded film, which comprises a layer formed with a thickness of 50 1/3.

In the above invention products, the measuring method of each property was as follows.

MI (g / 10 min) ； JIS K6760 = ASTM D1238 (190 ℃) Density (g / cm ³ ) ； JIS K6760 = ASTM D1505 Vicat softening point (℃) ； JIS K7206 = ASTM D1525 Experimental results are shown in Table 1. .

On the other hand, a part of the film to be tested was similarly cut and adhered to the inclined surface, the film surface of the block was placed on the inclined surface, the inclination angle of the inclined surface was changed, and the block began to slide. The angle θ was read.

〔The invention's effect〕

Since the present invention adheres by blocking and uses the ethylene acrylic acid ester-based resin film layer, it is flexible and excellent in antistatic property, and physical strength such as tear strength, gel body strength, burst strength, impact drilling strength is significantly improved. Then
In addition, curling does not occur, and unlike a laminated film using an adhesive, bonding equipment and the like can be omitted, so that it can be provided at low cost. Further, it has become possible to block off the bad odor of ethylene acrylate resin, which has been a problem in the past.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 to FIG. 7 are partial cross-sectional views showing a layer structure of an embodiment of a packaging material according to the present invention. 1 ... Ethylene acrylate resin film layer (inner layer) 2 ... Thermoplastic resin film layer (outer layer) 3 ... Two-layer coextrusion inflation film 4 ... Intermediate layer 5 ... Three-layer coextrusion inflation film 6 ... ... four-layer coextrusion blown film a: Shows that it has a light-shielding property.

Claims (1)

[Claims] 1. A laminated packaging material comprising a pseudo-adhesive layer obtained by adhering two layers of an ethylene acrylate resin film, which is an inner layer of a multilayer co-extruded film, by blocking.