JPS63169641A - Wrapping material for photosensitive substance - Google Patents

Abstract

PURPOSE:To obtain the titled material having the good bag making property and the improved packaging workability, without generating any curling of the titled material by inserting a film layer composed of a thermoplastic resin film having light reflection property between the thermoplastic resin film having a light absorptive property and a flexible sheet layer. CONSTITUTION:The film layer 2a composed of the thermoplastic resin having the light reflection property is a shade film layer having the light reflection property which is formed by adding a shade substance having the light reflection property to the thermoplastic resin, and the thermoplastic resin film layer 3a having the light absorptive property is the shade film layer having the light absorptive property which is formed by adding the shade substance having the light absorptive property to the thermoplastic resin. The film layer 4a is formed by coextruding the film layers 2a and 3a. As the flexible sheet layer 1 is laminated on the surface of the film layer 2a side of the layer 4a, the curling of the titled material does not generate, even in case of making the titled material to a thin layer.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a packaging material for photosensitive materials, particularly photographic materials that require all of the various properties.

[Conventional technology]

Various types of packaging materials for photographic materials are in widespread use, including light-shielding, moisture-proofing, gas-barrier, and
Performance such as physical strength is required.

By the way, a light shielding material 5 is placed on only one side of the flexible sheet, for example, metal foil or aluminum vacuum-deposited film (nylon resin film, polyester resin film, polyethylene resin film, polypropylene resin film, etc.).
1 Contains heat b] Films laminated with plastic resin films (high-pressure processed low-density polyethylene (hereinafter referred to as LDPE) resin films, linear low-density polyethylene (hereinafter referred to as L-LDPE) resin films, etc.) do not contain light-shielding substances. Very large curling occurred on the containing thermoplastic resin film side, making bag making impossible.

Conventionally, therefore, heat-resistant paper, nonwoven fabric, biaxially oriented film (nylon resin film, polyester resin film, high-density polyethylene resin film, etc. film, polypropylene resin film, etc.), -
By fully laminating various types of thermoplastic resin films including an axially oriented film and a light-shielding material, curling was completely reduced and practical use was attempted.

Examples of such conventional packaging materials include those shown in FIGS. 18 to 21.

The packaging material in Fig. 18 consists of LDPE resin light-shielding film layer 1
Al is a 5-layer laminated film in which an aluminum foil layer 11 is laminated on 0a through an adhesive layer 5, and a flexible sheet layer 1' made of bleached kraft paper is further laminated through an adhesive layer 5.

The packaging material shown in FIG. 19 is a packaging material that is often used as a roll photosensitive material and requires high physical strength.In the packaging material shown in FIG. Resin light shielding film layer 1
It is a laminated film with a seven-layer structure in which 000 is further laminated.

The packaging material shown in FIG. 20 is a laminated film in which a uniaxially stretched film 12a is fully laminated on both sides of an aluminum foil layer 11 via an adhesive layer 5 gold.

The packaging material shown in FIG. 21 has a metal vapor deposited film 13' on the thermoplastic resin film layer 14! i- Formed metallized film layer 1
L-LDPE of 50% by weight or more on both sides of 4m
It is a laminated film in which a single layer of polyethylene polymer 15@, 15a'ji containing a resin and a light-shielding substance is laminated, and the strength and layer thickness difference of this single layer of polyethylene polymer have a specific relationship (I\\j Publication No. 61-54934).

[Problem that the invention seeks to solve]

However, although the packaging materials shown in Figures 19, 20, and 21 reduce curling and have good bag formability, they require an additional layer to be laminated on the opposite side of the thermoplastic resin light-shielding film layer. It was expensive, thick and stiff, and had poor packaging workability. The packaging material shown in FIG. 18 did not sufficiently remove curling, could not be put to practical use unless under special bag-making conditions, was expensive, and had poor packaging workability.

In addition, in the packaging materials shown in Figures 19, 20, and 21, when carbon black is used as the light-shielding material, the surface is a thermoplastic resin light-shielding film layer coated with carbon black, so the commercial value is low. As packaging materials for special users such as manufacturers that use large quantities have declined, packaging materials are rarely used.

Furthermore, because the surface is black, it is difficult to distinguish the front and back under safelights used to package photosensitive materials, and it is difficult to pass the paper through processing machines.It also tends to fuzz due to abrasion during transportation, producing black powder that contaminates other products. There was. Furthermore, the high temperature caused by sunlight not only deteriorates the quality of the photosensitive material in the packaging material, but also causes melt adhesion under strong sunlight in summer.

The present invention is a packaging material for photosensitive materials that solves the above problems, can be provided at low cost, does not cause curling, and can eliminate problems caused by a thermoplastic resin light-shielding film layer containing carbon black on the surface. The purpose is to provide

Means for Solving Problem C] In order to achieve the above object, the present invention has a light-reflecting thermoplastic resin film layer laminated between a light-absorbing thermoplastic resin film and a flexible sheet layer. .

That is, the packaging material for photosensitive materials of the present invention includes a multilayer coextruded film layer having a light-reflecting thermoplastic resin film layer and a light-absorbing thermoplastic resin film layer, and a light-reflecting thermoplastic IWJJli film of the multilayer coextruded film 1. The structure is characterized by comprising a flexible sheet layer laminated on the layer side.

The light-reflecting thermoplastic resin film layer is a light-reflecting light-shielding film layer obtained by adding a light-reflecting light-shielding substance to a thermoplastic resin. As this thermoplastic resin, polyolefin resin, polyester resin, polyamide resin, etc. are used, and among these, polyolefin resin is preferable.
In particular, high-density polyethylene (TDPE) resins, polypropylene resins, L-LDPE resins, or mixed resins containing these resins have good moisture resistance and low hygroscopicity even when a light-reflecting light-shielding material is added. is preferred.

As the light-reflecting light-shielding substance, metal powder, white or pale yellow pigment, etc. are used. The metal powder is aluminum powder, aluminum yeast, tin powder, nickel powder, zinc powder, or powder of these metal alloys or metal compounds.

Here, aluminum ester) and U, *-When making aluminum powder by a known method such as the lumill method, stamp mill method or atomization method, the presence of mineral spirit and a small amount of higher fatty acids such as stearic acid or oleic acid may also be used. It is made in the form of yeast. In the present invention, this aluminum yeast and polyolefin thermoplastic resins (various polypropylene resins, various polyethylene resins, EVA
resin, EEA resin, EAA m fat, etc.) are heated and kneaded, and low volatile substances (mainly mineral spirits with a strong odor) are removed using a vacuum pump, etc., and then used as aluminum paste compound resin and aluminum yeast master patch housing. .

In particular, it is preferable to use it as an aluminum-coated master patch resin in order to eliminate bad shadows and bad odors on photographic materials.

Particularly preferred is mineral spirit tJfl chair containing higher fatty acid 2o, i ~ 10% by weight aluminum powder with 90~99.9% by weight, completely covering the surrounding area with higher fatty acid, and thermoplastic metal powder. This is a resin that has been kneaded with the resin in the required amount.

Manen Aluminum Wam Powder refers to molten aluminum made into powder by the total atomization method, granulation method, rotating disk dropping method, evaporation method, etc., as well as aluminum foil f? - Pulverized into flakes by the Lumille method or Stang mill method, etc., and contains the following gold. Since aluminum powder alone is unstable, various known treatments are used to make the aluminum powder surface completely inert.

The amount of the metal powder added is preferably 0.1 to 20% by weight, particularly preferably 1 to 6% by weight tD g:1',
, is enclosed.

Moreover, the thickness of this light-reflecting thermoplastic resin film layer is 1
The thickness is preferably 0 μm or more, particularly preferably 20 μm or more.

The light-absorbing thermoplastic resin film layer is a light-absorbing light-shielding film layer obtained by adding a light-absorbing light-shielding substance to a thermoplastic resin. This thermoplastic resin is preferably an ethylene copolymer resin, and particularly preferably an L-LDPK resin. The product names of this L-LDPE resin include Uniball (UCC), Dowlex (Dow Chemical), Sflare (5-'Yupon Kanata), Marlex (Filinogs), Neozex and Waldzex (Mitsui Petrochemical Co., Ltd.). ), 8 stone Nilex (Japan Petrochemical), Stamilex (DSM), Idemitsu Moretic (Idemitsu Petrochemical), etc. As an α-olefin, butene-
1, octene-1, hexene-1,4-methylpentene-1, hegetene-1, octene-1, etc. are used, and the amount thereof is about 0.5 to 15 molti of the polymer. The density is generally considered to be about that of low-medium pressure polyethylene resin, but many commercially available products are in the range of 0.87 to 095 g^3.

Among these L-LDPE resins, ethylene-containing smooth 9 is particularly preferable from the viewpoint of physical strength and heat seal strength.
0 to 99.5 molti, alpha-' olefin content 0.5
~10 molti, melt index (hereinafter referred to as Ml)
is O, S ~ 3011/10 minutes CJIS K6760),
Density is 0.870~0.94097cm (JTS K
6760), and is obtained by a liquid phase process in which the α-olefin has 6 to 8 carbon atoms.

The most preferred representative examples are 4-methylpentene-1, which has 6 carbon atoms, artificially introduced into polyethylene as an α-olefin side chain, and is produced by Kumitsui Petrochemical ■'s Urtozex, and α-olefin side chain. -8 carbon atoms as olefin side chain
There are DSM's Stamilex, Dow Chemical's Dowlex, and Idemitsu Petrochemical's Idemitsu Moretex, all of which have introduced octene-1. (All of the above three companies are L-LDPE resins obtained by a liquid phase process.) Carbon black, iron oxide, etc. are used as the light-absorbing light-shielding substance.

An example of the classification of carbon black by raw material is as follows:
There are Supranok, oil furnace black, anthracene black, acetylene black, oil smoke, powder smoke, animal black, Pejitapu black, etc. Furnace car and 47 black are preferred for the purpose of improving light-shielding properties, cost, and physical properties, and acetylene curtain black and Ketjen carbon black are preferred as light-shielding substances that are expensive but have an antistatic effect.

It is also preferable to mix the former and the latter according to the required characteristics, if necessary. On the other hand, among these carbon blacks, those with p+ (5 to 9, average particle size 10 to 5Qmμ) are preferable, especially those with p!-15 to 9, average particle size 15 to 30
mμ furnace carbon black is preferred. By using all of these particles with a smaller diameter, there is less increase or decrease in capri and photosensitivity, and the light-shielding ability is large.
Furthermore, even when added to L-LDPE resin, it is possible to obtain a packaging material that has numerous advantages such as less occurrence of carbon black lumps and pinholes such as fish eyes, and improved physical strength.

The amount of the light-absorbing light-shielding substance added is preferably 0.1 to 20 g, particularly preferably 1 to 6 g.

To be sure, the thickness of this light-absorbing thermoplastic resin film layer is 1
The thickness is preferably 0 μm or more, particularly preferably 20 μm or more.

The thickness of the light-reflecting thermoplastic resin film layer described in detail above is preferably 20 to 80 times the thickness of the multilayer coextruded film layer from the viewpoint of curl balance, physical strength, moisture resistance, cost, etc. Preferably it accounts for 35-65% of the thickness.

A multilayer coextruded film layer is formed by having the light-reflecting thermoplastic resin film layer and the light-absorbing thermoplastic resin film layer described above. The thickness of this multilayer coextruded film layer is
Preferably it is 35 μm or more, particularly preferably 50 μm or more. A flexible sheet layer is laminated on the light-reflecting thermoplastic resin film layer side of this multilayer co-pressed film layer.

As the flexible sheet layer, thermoplastic resin films such as various polyethylene resins, polyethylene copolymer resins, polypropylene resins, polyvinyl chloride resins, polyvinyl chloride resins, polyamide resins, polycarbonate resins, fluorine resins, and polyesters can be used. There are known films of resins and films of modified resins and mixed resins thereof. In addition, metal thin film processing films (typically aluminum vacuum-deposited films), acetate films,
Examples include cello, polyvinyl alcohol film, various papers, various metal foils (aldinium foil as a typical example), nonwoven fabric, warp, perforated film, and foamed sheets such as polyethylene, polystyrene, and polyurethane. Preferably,
Taselohan, acetate film, biaxially oriented thermoplastic resin film with good transparency and heat resistance, processed film made by coating these films with vinylidene chloride or other moisture-proofing and gas-barrier layers, metal thin film processing. It's a film.

When the flexible sheet layer is made fully transparent or semi-transparent, the surface of the flexible sheet layer appears silver, making it possible to distinguish between the front and back sides even under a safelight, improving workability, and having high commercial value, even under sunlight. The quality of the photosensitive material does not deteriorate due to temperature rise. Furthermore, a beautiful mark with less turbidity can be made with colored ink on the surface of the flexible sheet layer.

The thickness of this flexible sheet layer varies depending on the purpose of use, but is generally 6 to 1000 μm, preferably 7 to 1 μm.
00 Am.

The method for laminating the multilayer coextruded film layer and the flexible sheet layer may be any conventional method, such as a thermal bonding method (
Hot plate bonding method, impulse bonding method.

Ultrasonic bonding method), methods using adhesives (including wet lamination method, dry lamination method, hot melt lamination method, extrusion lamination method, coextrusion lamination method), etc. are used.

Typical adhesives include various polyethylene resins,
Polypropylene resin? Polyolefin thermoplastic resin hot melt adhesives such as ligten resin, olefin copolymers such as ethylene-propylene copolymer resin, ethylene-vinyl acetate copolymer resin, ethylene-ethyl acrylate copolymer resin, ethylene-acrylic acid There are thermoplastic resin heat melt adhesives such as copolymer resins and ionomer resins, geothermal melt type rubber adhesives, etc. Solution adhesives include wet laminating adhesives such as Aashi, Emulsilon, and latex adhesives. It is a drug. Emal, ).

Typical examples of adhesives include 71J vinyl acetate, vinyl acetate-ethylene copolymer, vinyl acetate and acrylic ester copolymer, vinyl acetate and maleate ester copolymer, acrylic acid copolymer, There are emulsions such as ethylene-acrylic acid copolymer. Typical examples of latex adhesives include natural rubber, styrene pudazoene (SBR)
), acrylonitrile pudazoene (NBR), chloroprene (CR), and other rubber latexes. Adhesives for dry lamination include polyurethane adhesives, and others include rough-in wax, microcrystalline wax, ethylene-vinyl acetate copolymer resin,
Known adhesives such as hot melt laminating adhesives blended with ethylene-ethyl acrylate copolymer resin, pressure-sensitive adhesives, heat-sensitive adhesives, etc. can be used. More specifically, polyolefin adhesives for extrusion lamination include polyolefin resins such as various polyethylene resins, polypropylene resins, and polybutylene resins, ethylene copolymer (EVA, EEA, etc.) resins, as well as linear low-density polyethylene ( L-LDPE) W
Like Fat, Echi V7 (7) and some other songs' monomer (α-
It also includes ionomer resins (ionic copolymer resins) such as olefin copolymer resins, DuPont's Surlyn, and Mitsui Polycarbonate's Atomer.

It is preferable that these adhesives have a melting point 5° or more lower than the flexible sheet layer to be laminated. A temperature difference of this degree does not adversely affect the flexible sheet layer and allows complete thermal melt bonding.

The thickness of the adhesive layer formed by extrusion lamination using a thermoplastic resin is usually 108 m to 500 m, preferably 15 m to 200 m.

Various additives can be added to each layer in required amounts as necessary.

Typical examples of additives are listed below, but the present invention is not limited thereto, and any known additives may be selected.

(Additives) (Representative example) (IIJff
I agent: phthalate ester, dalicol ester, JIW
Fatty acid ester, phosphate ester, etc. (2) Stabilizer; lead-based, cadmium-based, zinc-based, 7, V
Potassic earth metal type, organic tin type, etc. (3) Antistatic agent; cationic activator, anionic activator,
Nonionic activators, bifacial activators, etc. (4) Flame retardants; phosphoric acid esters, halogenated phosphoric esters, halides, inorganic substances, phosphorous-containing polyols, etc. (5) Fillers; alumina, kaolin, clay, calcium carbonate, mica, Talc, titanium oxide, silica, etc. (6) Reinforcement agent; lath roving, metal fiber, glass fiber, lath milled fiber, carbon fiber, etc. (7) Colorant; Inorganic pigment (AZ * F@ 205 *
(8) Blowing agents; Inorganic blowing agents (ammonia carbonate, sodium bicarbonate); Accelerators, accelerators, etc. (10 Deterioration inhibitors; UV absorbers, antioxidants, metal deactivators, peroxide decomposers, etc.6) Lubricants; Paraffin, wax, fatty acid-based, silicone-based, stearic acid Abad type, higher fatty acid metal salt type, bis fatty acid amide type, fatty acid amide type, aluamine type, ester type, higher alcohol, etc. (6) Coupling agent: silane type, titanate type, chromium type, aluminum Systems, etc. (2) Various thermoplastic resins, rubbers, etc. In addition, lubricants of 0.03 to 0.03% are added to the light-absorbing thermoplastic resin film layer in order to improve film formability and packaging of photosensitive materials.
It is preferable to add 1.0% by weight.

The packaging material for photosensitive materials of the present invention can be used to
Photosensitive materials that have deteriorated due to curing, e.g.

Used in the packaging of food products such as chocolate, margarine, basso, wine, beer, pharmaceuticals, ultraviolet curing films, ultraviolet curing resins, dyes, and other chemical substances, such as developing solutions, dyeing mordants, and photographic materials. It will be done.

In particular, photographic materials whose quality is destroyed by slight gas, light or humidity, such as silver halide photographic materials,
Ideal for packaging Soazo photographic materials, photosensitive materials, self-developing photographic materials, diffusion transfer photographic materials, etc.

When the packaging material for photosensitive materials of the present invention is used for packaging the above-mentioned photographic materials, single-child bags, 2. All known forms such as flat bags, square bottom bags, self-supporting bags, single-layer gusseted bags, double-layered gusseted bags, film sheets, moisture-proof box lining, and leader paper are possible.

The bag can be manufactured by conventionally known plastic film bonding methods such as hot plate bonding, impulse bonding, fusing bonding, ultrasonic bonding, and high frequency bonding.

Note that it is also possible to make bags using an adhesive method using glue, an adhesive method using pressure-sensitive/thermal adhesive sound, or the like.

[Effect]

The packaging material for photosensitive materials of the present invention has a multi-layer coextruded film layer consisting of a light-absorbing thermoplastic fat-resistant film layer and a light-reflecting thermoplastic resin film layer, all of which are coextruded. rarely occurs. Furthermore, when a transparent flexible sheet is used, the silver color of the light-reflecting thermoplastic resin film layer is visible from the outside.

〔Example〕

Example t of the packaging material for photosensitive materials of the present invention will be described based on FIGS. 1 to 6.

1 to 6 are partial cross-sectional views showing the layer structure of the packaging material for photosensitive materials.

The packaging material for photosensitive materials shown in Figure 1 consists of a single flexible sheet layer 1, a light-reflecting thermoplastic resin film layer 2
A and a multilayer coextruded film layer 4a consisting of a light-absorbing thermoplastic resin film layer 31 are laminated with an adhesive layer 5 interposed therebetween. As shown in FIG. 7, this packaging material hardly causes curling.

In the packaging material for photosensitive materials shown in FIG. 2, the flexible sheet layer 1 is formed of two coextruded flexible sheet layers 1' and 1'', and the critical area is the same as that of the packaging material for photosensitive materials shown in FIG.

The packaging material for photosensitive materials shown in Fig. 3 is made of light-shielding simultaneous multilayer coextrusion consisting of three layers, with an intermediate layer 6' laminated between a light-reflecting thermoplastic resin film layer 2a and a light-absorbing thermoplastic resin film layer 3a. The film 4&nine is the same as the packaging material for photosensitive material shown in FIG.

The packaging material for photosensitive materials shown in FIG. 4 is the same as the packaging material for photosensitive materials shown in FIG. 1, except that a flexible sheet layer 1 whose surface has been treated with a coating layer 7 is used.

The packaging material for photosensitive materials shown in FIG. 5 is the same as the packaging material for photosensitive materials shown in FIG. 1, except that it uses a flexible sheet layer 1 whose surface is treated with a metal thin film 8 represented by an aluminum vacuum-deposited film layer. .

The packaging material for photosensitive materials shown in FIG.
The nine metal foil layers 9 laminated via the adhesive layer 5 are the same as the packaging material for photosensitive materials shown in FIG.

FIGS. 8 to 11 are partial cross-sectional views showing the layer structure of comparative examples.

The comparative example in FIG. 8 is a light-absorbing thermoplastic resin film layer 3a.
, 3a and the flexible sheet layer 1 are laminated with an adhesive layer 5 interposed therebetween. In the laminated film of this comparative example, large curling occurred as shown in FIG. 12.

In the comparative example shown in FIG. 9, a light-absorbing thermoplastic resin film layer 3 and a flexible sheet layer 1 are laminated with an adhesive layer 5 in between. As shown in FIG. 13, the laminated film of this comparative example suffers from curling in a cylindrical shape with two or more turns.

In the comparative example shown in FIG. 10, the light-reflecting thermoplastic resin film layer 2
m and the flexible sheet layer 1 are laminated with an adhesive layer 5 interposed therebetween. As shown in FIG. 14, the laminated film of this comparative example has somewhat improved curling, but is still difficult to put into practical use.

In the comparative example shown in FIG. 11, the surface is treated with a metal thin film 8 typified by an aluminum vacuum-deposited film layer, followed by a flexible sheet layer, a light-absorbing thermoplastic resin film layer 3 m thick,
A two-layer coextruded film layer 171 having a thickness of 3 m is laminated with an adhesive layer 5 interposed therebetween. In the laminated film of this comparative example, as shown in FIG. 13, very large curling occurred.

In addition, FIG. 15 is a cross-sectional view showing the curling state of the multilayer coextruded film layer 4 consisting of the light-reflecting thermoplastic resin film layer 2 and the light-absorbing thermoplastic resin film layer 3, and shows the difference in shape of the additives. and curls toward the light-reflecting thermoplastic resin film layer 2a side due to the difference in hygroscopicity.

FIG. 16 is a cross-sectional view of the curling state of the two-layer coextruded film layer 17m consisting of the light-absorbing thermoplastic resin film layer 3m. Since the additives and hygroscopicity are the same, it is almost flat and curling is not observed. Almost never occurs.

FIG. 17 is a sectional view showing a curling state of a single layer film of the light-absorbing thermoplastic resin film layer 3, and no curling occurs.

Next, products I to (■) of the present invention, comparative product I, and conventional product I.

Table 1 shows the experimental results comparing the characteristics of (2).

The evaluation in the table is based on the following.

◎; Very good O; Excellent ・: Within practical limits; Problems and improvements needed ×; Test method not practical *A (curling state) A laminated film with a diameter of 10 cm that should be tested! A circular test sample of No. 8 was prepared, and the temperature was 20°C and the humidity was 65% RH.
After being left under a 1 kg load plate for 24 hours in an atmosphere under the above conditions, each circular test sample was left unloaded on a flat plate for 24 hours in the atmosphere under the above conditions, and then the curling state was evaluated.

Test method * (Cost ratio) Laminated film 1 when conventional product ■ is set as 100? Cost ratio per M, that is, price of conventional laminated film ■ per m υ rym>Xi
OO = cost ratio and the following test method *c (distinguishability of front and back under safelight and workability)
Determining the ease of distinguishing the front and back sides of a laminated film using a safelight for rolled color photographic paper, and the ease of packaging rolls of color photographic paper using an automatic bag-making machine with the entire circumference of the laminated film.

Test method *2 (Temperature rise under sunlight) After leaving the laminated film with the non-heat-sealed side (flexible sheet layer 1) facing up and leaving it under 80,000 lux sunlight for 1 hour, the surface temperature of the laminated film increased. Judging by the feel of the hand.

Test method *E (tear strength (vertical)) Conforms to JIS P8116.

[Effects of the Invention] Since the present invention is constructed as described above, it is possible to provide a packaging material for photosensitive materials that is inexpensive and has good bag-making and packaging workability without causing curling even if it is a thin layer.

[Brief explanation of the drawing]

Figures 1 to 6 are partial sectional views of embodiments of the packaging material for photosensitive materials according to the present invention, Figure 7 is a diagram showing the curling state of the embodiment of Figure 1, and Figures 8 to 11. 12 to 14 are diagrams showing the curling state of the comparative product, Figures 15 to 17 are diagrams showing the curling state of other films, and Figures 18 to 18 are diagrams showing the curling state of other films. 21 to 21 are partial cross-sectional views of conventional packaging materials. DESCRIPTION OF SYMBOLS 1...Flexible sheet layer, 21A...Light-reflecting thermoplastic resin film layer, 3-layer...Light-absorbing thermoplastic resin film layer, 41...Multilayer coextruded film layer, 5.
... Adhesive layer, 6... Intermediate layer, 出... Indicating that it has light-shielding properties Patent applicant Fuji Photo Film Co., Ltd. Representative Patent attorney Masahiro Tanaka and one other person Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 2

Claims (1)

[Claims] A multilayer coextruded film layer having a light reflective thermoplastic resin film layer and a light absorbing thermoplastic resin film layer, and a flexible sheet layer laminated on the light reflective thermoplastic resin film layer side of the multilayer coextruded film layer. Packaging material for photosensitive materials characterized by