JPH04349456A - Packaging material for photographic sensitive material and packaging bag formed by using this material - Google Patents

Abstract

PURPOSE:To improve heat sealability, moistureproofness, oxygen barrier property, dustproofness, etc., while well maintaining easy tearability. CONSTITUTION:An outside layer 2 consisting of a biaxially stretched thermoplastic resin film is laminated via an adhesive later 3 to one side of an intermediate layer 1 consisting of metallic foil. An inside layer 4a consisting of a nonstretched polyolefin resin film added with a light shieldable material is laminated via an adhesive layer 3 to the other side of the intermediate layer 1.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention has moisture-proofing properties, oxygen barrier properties,
It has excellent antistatic properties and heat sealing properties, and can be completely sealed.
The present invention also relates to an easy-to-open packaging material for photographic materials and a packaging bag using the same.

0002

[Prior Art] Conventionally, easy-to-open packaging materials for photographic materials include lubricants, light-shielding substances, and 50 wt% or more LD.
The inner layer containing PE resin and the aluminum foil layer (intermediate layer) that formed the anchor coat layer have a peel strength of 400g/15
There is an easy-to-open packaging material for photographic materials in which the outer layer is laminated with a width of mm or more and has a heat resistance of 5° C. or higher than that of the inner layer (Japanese Utility Model Publication No. 2-19226).

0003

However, the above-mentioned conventional packaging materials for photographic materials do not have sufficient heat-sealing properties, and improvements in dustproof properties, physical strength, etc. have also been desired.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a packaging material for photographic materials that has good tearability and improved heat-sealing properties.

[0005]

[Means for Solving the Problems] The present invention has been made to achieve the above object, and consists of an outer layer made of a biaxially oriented thermoplastic resin film or cellophane, a metal layer or a polyamide resin film, and an ethylene vinyl alcohol film. It has an intermediate layer made of a polymer resin film or a polyacrylonitrile resin film, and an inner layer made of a polyolefin resin film containing one or more types of lubricants and conductive substances and 10% by weight or more of an ethylene copolymer resin. The structure is characterized by an adhesive strength of 250 to 2000 g/15 mm width.

[0006] Biaxially stretched thermoplastic resin films are produced by a known biaxial stretching method such as simultaneous biaxial stretching or sequential biaxial stretching, by 1. The film is stretched 5 to 20 times, preferably 3 to 15 times. Thermoplastic resins used for this film include polyester resin, polyamide (nylon) resin, polyethylene resin, polystyrene resin, polypropylene resin, polyolefin copolymer resin, polyvinyl chloride resin, polyvinylidene chloride resin, and ethylene vinyl alcohol copolymer resin. Copolymer resins, vinylon resins, etc., and copolymer resins of these resins and other resins (including not only binary copolymer resins but also ternary or more copolymer resins. The copolymer type is random copolymer resin) (Polymerization or block copolymerization may be used.), mixed resins of the above resins and other resins, etc.

[0007] The above-mentioned polyester resins include resins synthesized from dimethyl terephthalate and ethylene glycol, dimethyl terephthalate and 1,4-cyclohexanedimethanol, dimethyl terephthalate, dimethyl isophthalate, and the like. Polyamide resin includes nylon 6,
Examples include nylon 66, nylon 12, nylon 11, and nylon 6-66 copolymer resins.

[0008] These resins are then biaxially stretched using a T-die film molding machine or a blown film molding machine to form a film.

The thickness of this biaxially stretched thermoplastic resin film is preferably 5 to 70 μm, particularly preferably 7 to 50 μm, and 10 to 35 μm in order to reduce the thickness of the packaging material, reduce costs, and ensure physical strength. Most preferred. Thickness is 5
If it is less than μm, wrinkles or cuts are likely to occur during the lamination process, and if it exceeds 70 μm, the rigidity is too high, resulting in poor bag-making properties, Gelbo test strength, and handling properties, as well as being expensive.

[0010] In addition, in order to improve light-shielding properties, prevent glare from the metal layer, and improve lubricity, a translucent, white, yellow, or silver appearance can be achieved by selecting various resins and adding additives selected from various additives. It is preferable to In the present invention, translucent means that the haze measured by ASTM D 1003 is 2.
5% to 98%, preferably 40 to 90%. Further, the biaxially stretched thermoplastic resin film may be a single layer or a multilayer coextruded film having two or more layers. It is preferable that the difference in elongation at break in the length and width is within 2 times, preferably within 1.5 times, in order to make it easy to tear by hand without any difference in length and width.

[0011] As the cellophane, use commercially available products such as ordinary cellophane specified in JIS Z 1521, or moisture-proof cellophane in which the surface of ordinary cellophane is coated with salt-vinyl acetate copolymer resin, vinylidene chloride resin, etc. be able to.

[0012] The metal layer is made of aluminum foil, iron foil, tin foil,
Metal foil such as lead foil, electrolytic iron foil, stainless steel foil, copper foil, etc., with a thickness of preferably 5 to 50 μm, particularly preferably 6 to 3 μm.
0 μm, most preferably 7-20 μm. In particular, aluminum foil with a thickness of 6 to 15 μm is preferred because it is inexpensive and has little adverse effect on photographic materials. Furthermore, the metal layer may be a thin metal film processed into a flexible sheet or the like. As this metal thin film, for example, there is an aluminum vapor deposited film.

[0013] The thickness of the aluminum vapor-deposited film is preferably 55 to 1200 Å from the viewpoint of securing physical strength, light-shielding properties, antistatic properties, moisture-proofing properties, gas barrier properties, etc. as a laminate, cost, and quality. That is, if the thickness is less than 55 Å, the moisture proofing and gas barrier properties are insufficient, and it is not possible to reduce the electrification generated in the layers on both sides of the aluminum vapor deposited film. Moreover, if the thickness exceeds 1200 Å, antistatic properties, gas barrier properties, moisture proof properties, and light blocking properties can be ensured, but the cost and
Vacuum deposition methods and the like have problems in that the flexible sheet deteriorates due to heating and the physical strength of the resulting laminated film decreases. In particular, for use in packaging materials for ordinary photographic materials,
A thickness of 800 Å is preferred, more preferably 100-
It is 600 Å.

[0014] In order to process the aluminum vapor deposition film, vacuum vapor deposition method, sputtering method, ion plating method,
This is done using an electron beam evaporation method, etc.

[0015] Furthermore, the aluminum vapor-deposited film may be processed not only on one side of the flexible sheet but also on both sides. It is preferable to apply a physical or chemical surface activation treatment such as applying an anchor coating agent to the surface of the flexible sheet or subjecting it to corona discharge treatment, since this can also increase the adhesive strength of the aluminum vapor deposited film.

A protective layer can be provided on the aluminum vapor-deposited film to prevent scratching and peeling. This protective layer includes petitral resin, acrylic resin, cellulose resin such as cellulose acetate, urethane resin, epoxy resin,
Appropriate resins such as polyester resins, ionomer resins, ethylene-ethyl acrylate copolymer resins, various polyethylene resins, and polypropylene resins can be used. Further, wax, gelatin, polyvinyl alcohol, etc. can also be used.

[0017] The protective layer is preferably formed with an extremely thin thickness.
Even when provided by extrusion lamination, static electricity will not be removed sufficiently unless the thickness is 50 μm or less. A dry film thickness of 5 μm or less by a known solution coating method, spray coating method, etc. can protect the aluminum vapor-deposited film and is highly effective in removing static electricity.

[0018] Physical surface treatment and AC
Specific examples of agent treatment are shown below.

Representative examples of physical surface treatments are shown below. Flame treatment: Running costs are high and there is a risk of fire. Plasma treatment: convert argon gas etc. into plasma and treat the surface. The physical strength is several times higher than corona discharge treatment, but the equipment cost is also several tens of times higher than corona discharge treatment machines. Corona discharge treatment: Substrates that can be treated include paper, various polymer films, sheets, aluminum foil, aluminum vacuum-deposited film, etc. It is the most commonly used, inexpensive and highly effective treatment. Sandblasting: The surface is roughened by blasting silica, etc. at high pressure. Chemical treatment: Surface treatment with dichromic acid solution, etc. Ozone treatment: Surface treatment in a box filled with ozone. Preheat treatment: Heat treatment of flexible sheets such as films and paper using heater drums, hot air, etc.

Other methods include ultraviolet irradiation treatment, high frequency heating treatment, electric induction heating treatment, and microwave treatment.

AC agent treatment is performed using AC agent (An
This is done by applying chor coating agent. This AC agent is different from a simple adhesive, and is also called a primer, adhesive promoter, etc. in the sense that it chemically adheres. Representative examples of AC agents are described below. (1) Organic titanate (titanium-based) AC agent Tetra
-propyl-titanate or Tetra
-Iso-butyl-titanate is the main component, and Tetra-stearyl- is used as a hydrolysis regulator.
Use with addition of titanate. (2) Polyethyleneimine (imine type) AC agent Polyethyleneimine (-CH2-CH2-NH-n) having a relatively high degree of polymerization is used. It is particularly preferred because it is easy to manage and has a long pot life (shelf life). (3) Isocyanate-based AC agent There are two types: one that uses a polymer with isocyanate groups alone (one-component type) and one that uses it in combination with polyester, etc. that has OH groups (two-component type). A chemical reaction occurs and an adhesive effect appears. The disadvantages are that it has a short pot life and is expensive. (4) Polyester-based and urethane-based AC agents Saturated polyester resins and urethane resins are used by dissolving them in a solvent such as ethyl acetate or toluene. (5) Polyolefin AC agent (6) Polybutadiene AC agent

[0022] The AC agent layer is preferably formed to have an extremely thin thickness. As a coating method for the AC agent, a gravure roll coating method, a kiss roll coating method, a drop coating method, a bar coating method, a reverse roll coating method, a direct roll coating method, an air knife coating method, etc. are used.

[0023] Two or more of the above physical surface treatments may be used in combination, or a physical surface treatment and an AC agent treatment may be combined.

[0024] The polyamide resin film has amide bonds (
-CONH-) is a general term for films manufactured using synthetic polymer compounds having -CONH-), and is generally called nylon film. Types include nylon 6 and nylon 66.
There are films such as , nylon 6-10, nylon 11, and nylon 12.

Ethylene vinyl alcohol copolymer resin film has the highest oxygen gas barrier property among various plastic films. It is a random copolymer of ethylene and vinyl alcohol, generally called EVOH resin, and is a film made from a thermoplastic resin currently manufactured and sold in Japan by Kuraray Co., Ltd. and Nippon Gosei Kagaku Kogyo Co., Ltd.

[0026] The polyacrylonitrile resin film contains acrylonitrile, methacrylonitrile,
The nitrile component of fumaronitrile and maleonitrile is 50%
A film that uses a resin containing at least % by weight and has oxygen gas barrier properties. Generally called PAN resin. It is a film made from thermoplastic resin, which is currently manufactured and sold in Japan by Mitsui Toatsu Chemical Co., Ltd. and Asahi Kasei Kogyo Co., Ltd.

The polyolefin resin film layer has 10
% or more by weight of ethylene copolymer resin. Representative examples of ethylene copolymer resins are shown below. (1) Ethylene-vinyl acetate copolymer resin (2) Ethylene-propylene copolymer resin (3) Ethylene-1
-Butene copolymer resin (4) Ethylene-butadiene copolymer resin (5) Ethylene-vinyl chloride copolymer resin (6) Ethylene-methyl methacrylate copolymer resin (
7) Ethylene-methyl acrylate copolymer resin (8)
Ethylene-ethyl acrylate copolymer resin (hereinafter referred to as EE)
(Displayed as A resin) (9) Ethylene-acrylonitrile copolymer resin (1
0) Ethylene-acrylic acid copolymer resin (11) Ionomer resin (resin in which a copolymer of ethylene and unsaturated acid is crosslinked with metal such as zinc) (12) Ethylene-α olefin copolymer resin (L- L
DPE resin) (13) Ethylene-propylene-butene-1 terpolymer resin

Among the ethylene copolymer resins, L-LDPE resin and EEA resin are preferred because they have good film moldability and heat sealability, and have high bag-breaking strength, impact puncturing strength, and tearing strength.

[0029] L-LDPE (Liner Low De
Polyethylene resin is called the third type of polyethylene resin, and is a low-cost, high-strength resin that has the advantages of both medium-low density and high-density polyethylene resins and meets the demands of the times for energy and resource conservation. This resin is a copolymer made by copolymerizing ethylene with an α-olefin having 3 to 13 carbon atoms, preferably 4 to 10 carbon atoms, using a low-pressure method or a high-pressure modification method, and has a linear straight chain structure with short branches. It is a polyolefin copolymer resin. Preferred α-olefins in terms of physical strength and cost include 1-butene, 1-octene, 1-hexene-1,4-methylpentene, and 1-heptene. The density is generally considered to be about that of low-medium density polyethylene resin, but many commercially available products have a density within the range of 0.87 to 0.95 g/cm3. Many have a melt index within the range of 0.1 to 50 g/10 minutes.

The polymerization process for L-LDPE resin includes a gas phase method using medium/low pressure equipment, a liquid phase method, and an ionic polymerization method using a high pressure modified equipment.

Among these L-LDPE resins, those having a melt index (hereinafter referred to as MI) of 0 are particularly preferable from the viewpoint of physical strength, heat sealing strength, and film formability.
．． 8-10g/10min (JIS K-6760), density 0.870-0.940g/cm3 (JIS K-6760)
6760), and α-olefins having 6 to 8 carbon atoms obtained by a liquid phase process and a gas phase process.

Specific examples of commercially available L-LDPE resins are shown below. Ethylene-butene-1 copolymer resin G resin and NUC-FLX (UCC) Dowlex
(Dow Chemical) Screar (DuPont Canada) Marex (Philips) Stamilex (DSM) Excellen VL (Sumitomo Chemical) Neozex (Mitsui Petrochemical) Mitsubishi Polyethylene-LL (Mitsubishi Oil Chemical) Nippon Oilx (Nippon Oil) Chemical) NUC Polyethylene-LL (Nippon Unicar) Idemitsu Polyethylene L (Idemitsu Petrochemical) Ethylene/hexene-
1 Copolymer resin TUFLIN (UCC) T
UFTHENE (Nippon Unicar) Ethylene/4-methylpentene-1 copolymer resin Urtozex (Mitsui Petrochemicals) Ethylene/octene-1 copolymer resin Stamilex (DSM) Dowlex (Dow Chemical)
Skrea (DuPont Canada) MORETEC (Idemitsu Petrochemical)

[0033] Particularly preferred representative examples are given by trade names of Urtozex and α- There are Idemitsu Petrochemical Co., Ltd.'s MORETEC, DSM's Stamilex, and Dow Chemical's Dowlex, which introduce octene-1 with 8 carbon atoms as the olefin side chain. This is the obtained L-LDPE resin.). Preferred representative examples obtained by the low-pressure gas phase process are Nippon Unicar Co., Ltd., which introduces hexene-1 with 6 carbon atoms as the α-olefin side chain.
There are TUFLIN from Yahoo! Co., Ltd. and TUFTHENE from UCC.

[0034] In addition, a recently released product with a density of 0.910g
Ultra-low-density linear low-density polyethylene resins with a density of less than /cm3, such as NUC-FLX from UCC and Excelen VL from Sumitomo Chemical Co., Ltd., are also preferred (in both products, the α-olefin is butene with 4 carbon atoms). -1). The EEA resins are manufactured by Union Carbide (USA), Nippon Unicar Co., Ltd., and Mitsubishi Yuka Co., Ltd. (USA).
), Sumitomo Chemical Co., Ltd., and Mitsui Polychemical Co., Ltd. As a specific example, the names of representative brands of EEA resins currently on the market by Nippon Unicar Co., Ltd. and their comonomer content;
Indicates melt index and density (comonomer content 6% or more according to NUC test method).

[0035]

[Table 1]

The above ethylene copolymer resin has 10
If it is less than % by weight, heat sealability, especially hot tack property, heat seal strength over time, sealing heat seal property, etc. will be insufficient, pinholes and peeling of heat seal parts will occur, and moisture proofing, gas barrier properties, light shielding properties, etc. will be insufficient. It becomes impossible to ensure properties essential for a packaging material for photographic materials, such as properties.

In addition, since the polyolefin resin film layer, which tends to generate static electricity, is placed on the photographic material side (to ensure heat sealability), it is particularly difficult to use when used as a packaging bag. In order to prevent the generation of static marks on the photographic material, it contains one or more of a conductive substance and a lubricant.

Representative examples of conductive substances are shown below. (1) Nonionic surfactants (typical ingredients polyoxyethylene glycols) (2) Anionic surfactants (typical ingredients polyoxyethylene glycols) (3) Cationic surfactants (typical ingredients quaternary) Ammonium salts) (4) Ampholytic surfactants (5) Alkylamine derivatives (6) Fatty acid derivatives (7) Various lubricants (8) Carbon black, graphite (9) Metal surface coating pigments (10) Metal powders, metal flakes (11 ) Carbon fiber (12) Metal fiber (13) Whisker (potassium titanate, alumina nitride, alumina)

Representative examples of the nonionic surfactants are shown below. Polyethylene glycol fatty acid ester, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene fatty alcohol ether, polyoxyethylene alkylphenyl ether, polyoxyethylene glycerin fatty acid ester, polyoxyethylene fatty amine, sorbitan monofatty acid ester, fatty acid pentaerythritol , ethylene oxide adducts of fatty alcohols,
Ethylene oxide adducts of fatty acids, ethylene oxide adducts of fatty acid aminos or fatty acid amides, ethylene oxide adducts of alkylphenols, ethylene oxide adducts of alkylnaphthols, ethylene oxide adducts of partial fatty acid esters of polyhydric alcohols, and other special Various nonionic antistatic agents described in Publication No. 63-26697, page 120, etc.

Representative examples of the anionic surfactants are shown below. Ricinoleic acid sulfate ester soda salt, various fatty acid metal salts, silinoleic acid ester sulfate ester sodium salt, sulfated ethylaniline oleate, olefin sulfate ester salts, oleyl alcohol sulfate ester sodium salt, alkyl sulfate ester salt, fatty acid ethyl sulfonate , alkyl sulfonate, alkylnaphthalene sulfonate, alkylbenzene sulfonate, succinate sulfonate, phosphate ester salt, etc.

[
Representative examples of the cationic surfactants are shown below. Primary amine salts, tertiary amine salts, quaternary ammonium salts, pyridine derivatives, etc.

Representative examples of the amphoteric surfactants are shown below. The conductive substances such as carboxylic acid derivatives, imidazoline derivatives, betaine derivatives, etc. are preferably added in an amount of 0.01 to 3.0% by weight.

The names of typical commercially available lubricants added to the polyolefin resin film layer and the names of manufacturers are listed below.

(1) Silicone oil lubricant; various grades of dimethylpolysiloxane and its modified products (Shin-Etsu Silicone, Toray Silicone), polymethylphenylsiloxane, olefin-modified silicone, polyether-modified silicone modified with polyethylene glycol or polypropylene glycol. , olefin/polyether modified silicone, epoxy modified silicone, amino modified silicone,
It is a silicone oil containing modified siloxane bonds such as alcohol-modified silicone. Among the silicone oils, olefin-modified silicone, polyether-modified silicone, olefin/polyether-modified silicone, etc. are particularly excellent. The silicone oil improves the coefficient of friction of the film when heated, reduces the sliding resistance that occurs during hot plate sealing by automatic packaging machines, and prevents wrinkles, resulting in a beautiful appearance and high sealing performance. It is possible to create a basis for obtaining a film that maintains the performance of sagging and adhesion to the packaged object. In addition, it is possible to prevent a decrease in gloss due to sliding and obtain a beautiful seal. In the present invention when silicone oil is used in combination, when performing sliding heat sealing, the high temperature friction coefficient can be made 1.4 or less.

[0045] Viscosity at room temperature is 50 to 100,000
A range of centistokes is preferred, more preferably 5 centistokes.
,000 to 30,000 centistokes is preferable. The amount added varies depending on the type and purpose of use, but it is 0.
01 to 1.0% by weight. Preferably 0.03-0.
5% by weight, particularly preferably 0.05-0.3% by weight.

[0046] There are many effects of adding silicone oil in the applications of the present invention as follows. ■Improve resin fluidity, reduce screw motor load, and prevent melt fractures. ■ Sufficient lubricity can be ensured without adding fatty acid amides that bleed out and become white powder. ■Reducing the coefficient of friction of the film in the heated state,
It improves the suitability for automatic bag making, prevents wrinkles during heat sealing and decreases in gloss due to sliding, and makes it possible to obtain beautiful sealed parts. (2) When used in combination with a light-blocking substance, the light-blocking ability can be improved, and even if the amount of the light-blocking substance that degrades physical properties is reduced, the light-blocking property can be maintained.

(2) Fatty acid amide lubricant; i. Saturated fatty acid amide-based lubricants ■Behenic acid amide-based lubricants; Diamid KN (Nippon Kasei), etc. ■Stearic acid amide-based lubricants: Aramide HT (Lion Oil), Alflo S-10 (Nippon Oil), Fatty Acid Amide S (Kao), Diamid 200 (Nippon Kasei),
Diamid AP-1 (Nippon Kasei), Amide S/Amide T (Nitto Chemical), Neutron-2 (Nippon Fine Chemical), etc.

ii. Unsaturated fatty acid amide-based lubricant ■Erucic acid amide-based lubricant; Alflo P-10 (NOF), Neutron-S (Nippon Fine Chemical), LUBROL (I・C・
I), Diamid L-200 (Nippon Kasei), etc. Oleic acid amide lubricant; Armoslip CP (Lion Akzo), Neutron (Nippon Fine Chemical), Neutron E-
18 (Nippon Fine Chemical), Amide O (Nitto Chemical), Diamid O-200/Diamid G-200 (Nippon Kasei)
, Alflo E-10 (NOF), Fatty Acid Amide O
(Kao) etc.

[0049]iii. Bis fatty acid amide lubricant ■ Methylene bis behenic acid amide lubricant; Diamid NK Bis (Nippon Kasei), etc. ■ Methylene bis stearic acid amide lubricant; Diamid 200 Bis (Nippon Kasei), Armowax (Lion Akzo) , Bisamide (Nitto Kagaku), etc. ■ Methylene bis oleic acid amide lubricant; Lubron O (Nippon Kasei), etc. ■ Ethylene bis stearic acid amide type lubricant; Armoslip EBS (Lion Akzo), etc. ■ Hexamethylene bis stearic acid amide type lubricant ; Amide 65 (Kawaken Fine Chemicals), etc. ■Hexamethylenebisoleic acid amide lubricant; Amide 60 (Kawaken Fine Chemicals), etc.

iv. Monoalkylolamide lubricant■
N-(2-hydroxyethyl)lauric acid amide-based lubricant; Tohol N130 (Toho Chemical), etc. ■ N-(2-hydroxyethyl) stearic acid amide-based lubricant; Amizole (Kawaken Fine Chemicals), etc. ■ N
-(2-hydroxymethyl) stearamide lubricant; methylolamide (Nitto Chemical), etc.

(3)
) Nonionic surfactant-based lubricants; Electro Stripper-TS-2, Electro Stripper-TS-3 (Kao Soap), etc.

(4) Hydrocarbon lubricant; liquid paraffin, natural paraffin, microwax, synthetic paraffin, polyethylene wax, polypropylene wax, chlorinated hydrocarbon, fluorocarbon, etc.

(5) Fatty acid-based lubricant; higher fatty acid (C1
(preferably 2 or more), oxyfatty acids, etc.

(6) Ester lubricant; lower alcohol ester of fatty acid, polyhydric alcohol ester of fatty acid,
Polyglycol esters of fatty acids, fatty alcohol esters of fatty acids, etc.

(7) Alcohol-based lubricant; polyhydric alcohol, polyglycol, polyglycerol, etc.

(8) Metal soap; higher fatty acids such as lauric acid, stearic acid, ricinoleic acid, naphthenic acid, and oleic acid, and Li, Mg, Ca, Sr, Ba, Zn, and Cd.
, compounds with metals such as Al, Sn, Pb, etc.

The above-mentioned lubricants are preferably added in an amount of 0.01 to 5.0% by weight, and in the case of fatty acid amide-based lubricants that have a large lubricity effect and are prone to bleed out, the amount is 0.01 to 5.0% by weight.
It is preferable to add 1 to 1.0% by weight.

Furthermore, the polyolefin resin film layer can be blended with other thermoplastic resins, rubber, various additives, and modifiers in order to improve various properties.

A light-shielding substance can be added to the packaging material for photographic light-sensitive materials of the present invention in order to ensure light-shielding properties.

Typical examples of light-shielding substances are shown below. (1) Inorganic compound A. Oxides...Silica, diatomaceous earth, alumina, titanium oxide, iron oxide, zinc oxide, magnesium oxide, antimony oxide, barium ferrite, strontium ferrite,
B. Beryllium oxide, pumice, pumice balloon, alumina fiber, etc. Hydroxide...aluminum hydroxide, magnesium hydroxide, basic magnesium carbonate, etc.C. Carbonates...calcium carbonate, magnesium carbonate, dolomite, dawsonite, etc.D. (Sulfite) sulfates...calcium sulfate, barium sulfate, ammonium sulfate, calcium sulfite, etc.E. Silicates...talc, clay, mica, asbestos,
F. Glass fiber, glass balloon, glass beads, calcium silicate, montmorillonite, bentonite, etc. Carbon...Carbon black, graphite, carbon fiber, carbon hollow spheres, etc.G. Others...Iron powder, copper powder, lead powder, aluminum powder, molybdenum sulfide, poron fiber, silicon carbide fiber, brass fiber,
Potassium titanate, lead zirconate titanate, zinc borate, barium metaborate, calcium borate, sodium borate, aluminum paste, talc, etc.

[0061]
(2) Organic compound wood flour (pine, oak, sawdust, etc.), shell fiber (almond, peanut, rice husk, etc.), cotton, jute, paper strips, cellophane strips, nylon fibers, polypropylene fibers,
Starch, aromatic polyamide fiber, etc.

[0062] Among these light-shielding substances, opaque inorganic compounds are preferable, and in particular, they have excellent heat resistance and light resistance, and are relatively inert substances, so light-absorbing carbon black, titanium nitride, and graphite are preferable. is preferred.

[0063] Examples of classification of carbon black by raw material include gas black, furnace black, channel black, anthracene black, acetylene black, Ketjen carbon black, thermal black, lamp black, oil smoke, pine smoke, animal black, vegetable black, etc. There is.

In the present invention, furnace carbon black is preferable for the purpose of improving light-shielding properties, cost, and physical properties, and as light-shielding substances that are expensive but have an antistatic effect, acetylene carbon black and Ketjen, which is a modified by-product carbon black, are preferable. Carbon black is preferred. It is also desirable to mix the former and the latter according to the required characteristics, if necessary. As mentioned above, there are various ways of blending the light-shielding substance into the polyethylene polymer, but the masterbatch method is preferable in terms of cost, prevention of workplace contamination, and the like. Japanese Patent Publication No. 40-26196, a known document, describes a method for preparing a masterbatch of polymer carbon black by dispersing carbon black in a solution of a polymer dissolved in an organic solvent; A method for preparing a masterbatch by dispersing black in polyethylene is described.

When used as a packaging material for photographic light-sensitive materials of the present invention, there is no fogging, little increase or decrease in photosensitivity, high light-shielding ability, and even when added to an L-LDPE resin film, it does not harden ( Among carbon blacks, it has a pH of 6.0 to 9.0, an average particle size of 10 to 120 mμ, a volatile component of 2.0% or less, and an oil absorption property that is less likely to cause pinholes such as pimples and fish eyes in the film. Furnace carbon black in an amount of 50 ml/100 g or more is preferable in terms of improved light-shielding properties, improved dispersibility, and less deterioration of physical properties.

[0066] In order to improve the light-shielding property as much as possible by adding the same amount, it is necessary to add a light-shielding substance to the inside (the side that comes into contact with the product when packaged, or the side that is heat-sealed in the case of a bag). desirable.

[0067] The above-mentioned light-shielding substance depends on the resin used, the machine used,
Depending on cost and other factors, there are powder colorants, paste colorants, moisturizing colorants, masterbatches, dyes and pigments, colored pellets, and the like.

[0068] The amount of the light-shielding substance added is preferably such that the overall optical density is 5 or more.

[0069] It is preferable to add an antioxidant in order to prevent coloring failure and the like. Representative examples of this antioxidant are shown below.

(a) Phenolic antioxidant 6-t-
Butyl-3-methylphenyl derivative, 2,6-di-t
-Butyl-P-cresol, 2,2'-methylenebis-(
4-ethyl-6-t-butylphenol), 4,4'-
butylidene bis(6-t-butyl-m-cresol),
4,4'-thiobis(6-t-butyl-m-cresol), 4,4-dihydroxydiphenylcyclohexane,
Alkylated bisphenol, styrenated phenol, 2
・6-di-t-butyl-4-methylphenol, n-octadecyl-3-(3',5'-di-t-butyl-4'
-hydroxyphenyl)propinate, 2,2'-methylenebis(4-methyl-6-t-butylphenol),
4,4'-thiobis(3-methyl-6-t-butylphenyl), 4,4'-butylidenebis(3-methyl-6
-t-butylphenol), stearyl-β (3,5-
di-4-butyl-4-hydroxyphenyl) propionate, 1,1,3-tris(2-methyl-4hydroxy-5-t-butylphenyl)butane, 1,3,5 trimethyl-2,4,6- Tris (3,5-di-t-butyl-
4-hydroxybenzyl)benzene, tetrakis[methylene-3(3',5'-di-t-butyl-4'-hydroxyphenyl)propionate]methane, etc.

(b) Ketone amine condensation antioxidant 6
-Ethoxy-2,2,4-trimethyl-1,2-dihydroquinoline, polymers of 2,2,4-trimethyl-1,2-dihydroquinoline, trimethyldihydroquinoline derivatives, etc.

(c) Allylamine antioxidant phenyl-α-naphthylamine, N-phenyl-β-naphthylamine, N-phenyl-N'-isopropyl-P-phenylenediamine, N·N'-diphenyl-P-phenylenediamine , N・N'-di-β-naphthyl-P-phenylenediamine, N-(3'-hydroxybutylidene)-
1-naphthylamine etc.

(d) Imidazole antioxidant 2-mercaptobenzimidazole, 2
-Zinc salt of mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, etc.

(e) Phosphite-based antioxidants Alkylated allyl phosphite, diphenylisodecyl phosphite, tris(nonylphenyl) phosphite, sodium phosphite, trinonylphenyl phosphite, triphenyl phosphite, etc.

(f) Thiourea-based antioxidant Thiourea derivative, 1,3-bis(dimethylaminopropyl)-2-
Thiourea etc.

(g) Other antioxidants useful for air oxidation, such as dilauryl thiodipropionate, etc.

Typical commercially available antioxidants are shown below. (1) Phenolic antioxidant; SUMILIZER BHT (Sumitomo), IRGANOX
1076 (Ciba Geigy), MARK AO-50 (
ADEKA ARGUS), SUMILIZER BP-76
(Sumitomo), TOMINOX SS (Yoshitomi), IRGAN
OX 565 (Ciba Geigy), NONOX WSP (
ICI), SANTONOX (Monsanto), S
UMILIZER WX R (Sumitomo), ANTAGEC
RYSTAL (Kawaguchi), IRGANOX 1035 (Ciba Geigy), ANTAGE W-400 (Kawaguchi), N
OCLIZER NS-6 (Shinko Ouchi), IRGANO
X1425 WL (Ciba Geigy), MARKAO-8
0 (ADEKA ARGUS), SUMILIZER GA-
80 (Sumitomo), TOPANOL CA (ICI), M
ARK AO-30 (ADEKA ARGUS), MARK
AO-20 (ADEKA ARGUS), IRGANOX31
14 (Ciba Geigy), MARK AO-330 (Adeka Argus), IRGANOX 1330 (Ciba Geigy), CYANOX 1790 (ACC), IRGA
NOX 1010 (Ciba Geigy), MARK AO-
60 (ADEKA ARGUS), SUMILIZER BP
-101 (Sumitomo), TOMINOX TT (Yoshitomi), etc.

(2) Phosphorous antioxidant; IRGAFOS
168 (Ciba Geigy), MARK 2112 (Adeka Argus), WESTON 618 (BorgWarner), MARK PEP-8 (Adeka Argus), U
LTRANOX 626 (Borg Warner), MAR
K PEP-24G (ADEKA ARGUS), MARK
PEP-36 (Adeka Argus), HCA (Sanko), etc.

(3) Thioether antioxidant; DL
TDP “YOSHITOMI” (Yoshitomi), SUMIL
IZER TPL (Sumitomo), ANTIOX L (NOF)
, DMTD “YOSHITOMI” (Yoshitomi), SUMI
LIZER TPM (Sumitomo), ANTIOX M (NOF), DSTP “YOSHITOMI”, SU
MILIZER TPS (Sumitomo), ANTIOX S (
NOF), SEENOX 412S (Cipro), MARK
AO-412 S (ADEKA ARGUS), SUMIL
IZER TP-D (Sumitomo), MARK AO-23 (
ADEKA ARGUS), SANDSTAB P-EPQ (
Sand), IRGAFOS P-EPQ FF (Ciba Geigy), IRGANOX 1222 (Ciba Geigy)
, MARK 329K (ADEKA ARGUS), WES
TON399 (Borg Warner), MARK 260
(Adeka Argus), MARK 522A (Adeka Argus), MARK 522A (Adeka Argus)
Argus) etc.

(4) Metal deactivator NAUGARD XL-1 (Uniroyal), MARK
CDA-1 (ADEKA ARGUS), MARK CDA
-6 (ADEKA ARGUS), LRGANOX MD-1
024 (Ciba Geigy), CUNOX (Mitsui Toatsu), etc.

[
Particularly preferred antioxidants are phenolic antioxidants, and commercially available products include various Irganox products from Ciba Geigy and Sumilizer from Sumitomo Chemical Co., Ltd.
BHT, Sumilizer BH-76, Su
milizer WX-R, Sumilizer B
P-101 etc.

In addition, 2,6-di-hybutyl-p-cresol (BHT), a low-volatility high molecular weight phenolic antioxidant (trade name Ireganox 1010, Ir
eganox 1076, Topanol CA,
Ionox 330, etc.), dilauryl thiodipropionate, distearyl thiopropionate, dialkyl phosphate, etc. It is effective to use one or more, especially two or more, in combination.

The amount added is, for example, 0.01 to 2.0% by weight when added to a polyolefin resin film.

[0084] If the amount added is less than 0.01% by weight, there is almost no effect of the addition. On the other hand, if the amount added exceeds 2.0% by weight, it may have an adverse effect on photographic films that utilize oxidation and reduction effects, and abnormalities may occur in photographic performance. For this reason, it is preferable to add the antioxidant in the minimum amount that will not cause color failure or spots.

Furthermore, when used in combination with carbon black etc., the oxidation prevention effect is mutually exerted. It is preferable to use a phenolic antioxidant, a phosphorus antioxidant, and carbon black in combination because it has little adverse effect on the photographic material and particularly exhibits the antioxidant effect.

[0086] In addition, various antioxidants disclosed on pages 794 to 799 of the Plastic Data Handbook (published by the KK Industrial Research Group) and various antioxidants disclosed on pages 327 to 329 of the Plastic Additive Data Collection (KK Chemical Industry Co., Ltd.) Antioxidants and PLASTICS AGE E
It is possible to select and use various antioxidants and the like disclosed in pages 211-212 of NCYCLOPEDIA Progress Edition 1986 (KK Plastic Age).

[0087] Each of the above layers is preferably laminated with a solution type adhesive layer made of a polyester resin or a polyether resin having an isocyanate group at the end. This solution type adhesive layer is preferable because it has high adhesive strength even if it is a thin layer, and can ensure flexibility and easy opening. In addition, since it undergoes reaction and solidification, there is little adverse effect on photographic materials.

[0088] Each of the above layers contains 5 to 40% adhesive resin.
It is also preferable to laminate with a polyolefin resin extrusion laminate adhesive layer containing % by weight.

The adhesive resin is a modified polyolefin resin obtained by graft-modifying a polyolefin resin and an unsaturated carboxylic acid, and includes, for example, a graft-modified polyethylene resin, a graft-modified polypropylene resin, and a graft-modified ethylene copolymer resin.

[0090] Unsaturated carboxylic acids are a general term including their derivatives, and typical examples include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, tetrahydrophthalic acid, mesaconic acid, angelic acid, and citraconic acid. acid, crotonic acid, isocrotonic acid, nadic acid, (
endocys-bicyclo[2,2,1]hept-5-ene-2,3-dicarboxylic acid), maleic anhydride, citraconic anhydride, itaconic anhydride, methyl acrylate, methyl methacrylate, ethyl acrylate, methacrylic acid Ethyl, butyl acrylate, butyl methacrylate, glycidyl acrylate, glycidyl methacrylate, monoethyl maleate, diethyl maleate, monomethyl fumarate, dimethyl fumarate, diethyl itaconate, acrylic amide, methacrylamide , maleic acid monoamide, maleic acid diamide, maleic acid-N-monoethylamide, maleic acid-
N,N-diethylamide, maleic acid-N-monobutylamide, maleic acid-N,N-dibutylamide, fumaric acid monoamide, fumaric acid diamide, fumaric acid-N-monoethylamide, fumaric acid-N,N-diethylamide , fumaric acid-N-monobutylamide, fumaric acid-N,N-diethylamide, fumaric acid-N-monobutylamide, fumaric acid-N,N-dibutylamide, maleimide, monomethyl maleate, dimethyl maleate, matacrylic acid Potassium, sodium acrylate, zinc acrylate, magnesium acrylate, calcium acrylate, sodium methacrylate, potassium acrylate, potassium methacrylate, N-butylmaleimide, N-phenylmaleimide, malenyl chloride, glycidyl maleate, dipropyl maleate , aconitic acid anhydride, sorbic acid, etc., and it is also possible to use them in combination.

Among these, acrylic acid, maleic acid, maleic anhydride and nadic acid are preferred, with maleic anhydride being particularly preferred.

[0092] The method for graft-modifying the unsaturated carboxylic acids in the modified polyolefin resin is not particularly limited. For example, Japanese Patent Publication No. 43-274, which is reacted in a molten state.
21, a method disclosed in Japanese Patent Publication No. 44-15422, etc., in which the reaction is carried out in a solution state, a method disclosed in Japanese Patent Publication No. 43-18144, etc., in which the reaction is carried out in a slurry state, and a method disclosed in Japanese Patent Publication No. 43-18144, etc., in which the reaction is carried out in a slurry state. Tokuko Sho 50-77, which reacts in the state
There are methods of disclosure etc. in Publication No. 493 and the like.

Among these methods, the melt-kneading method using an extruder is preferred because it is easy to operate and inexpensive.

The amount of unsaturated carboxylic acids to be used is determined by adjusting the amount of polyolefin resin base polymer (various polyethylene resins, various polypropylene resins, various polyolefin copolymer resins, polybutene-1 resin, poly-4 resin) to ensure adhesive strength.
-α-olefin copolymer resin such as methylpentene-1 and its copolymer resin) 0.01 per 100 parts by weight
~20 parts by weight, preferably 0.2 to 5 parts by weight.

An organic peroxide or the like is used to promote the reaction between the polyolefin resin and the unsaturated carboxylic acids.

Examples of organic peroxides include benzoyl peroxide, lauroyl peroxide, azobisisobutyronitrile, dicumyl peroxide, α,
α'bis(t-butylperoxydipropyl)benzene, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, 2,5-dimethyl-2,5-di(t-
butylperoxy)hexyne, di-t-butyl peroxide, cumene hydroperoxide, t-butyl-hydroperoxide, dicumyl peroxide, t-
Butyl peroxylaurate, t-butyl peroxybenzoate, 1,3 bis(t-butyl peroxyisopropyl)benzene, cumene hydroperoxide,
Examples include organic peroxides such as di-t-butyl-diperoxyphthalate, t-butylperoxymaleic acid, and isopropyl percarbonate, azo compounds such as azobisisobutyronitrile, and inorganic peroxides such as ammonium persulfate. .

[0097] These may be used alone or in combination of two or more. Particularly preferred is a decomposition temperature of 170°C.
di-t-butyl peroxide between ~200°C,
Dicumyl peroxide, 2,5-dimethyl-2,5
Di(t-butylperoxy)hexane, 2,5-dimethyl-2,5di(t-butylperoxy)hexane, 1
, 3-bis(t-butylperoxyisopropyl)benzene.

[0098] The amount of these peroxides added is not particularly limited, but is 0.00 parts by weight per 100 parts by weight of the polyolefin resin.
0.005 to 5 parts by weight, preferably 0.01 to 1 part by weight.

Representative examples of commercially available adhesive polyolefin resins are shown below. (1) Japan Petrochemical KK “
N Polymer” (2) Mitsui Petrochemical Industries KK
“ADMER” (3) Showa Denko KK
“ER RESIN” (4)
Mitsubishi Chemical Industries KK “Novatec-AP” (5) Mitsubishi Yuka KK
“MODIC” (6) Nippon Unicar KK
“NUC-ACE”

010
0] Adhesive strength between each layer is 250 to 2000g/15
The width is at least mm. If the adhesive strength is less than 250 g/15 mm width, easy openability will be lost. 100g/15mm
If the width is less than that, delamination is likely to occur.

Furthermore, if the adhesive strength exceeds 2000 g/15 mm width, pinholes are likely to occur due to the sharp edges of the photosensitive material, the tear strength will be greatly reduced, the bag will be easy to break, and the sealing performance will be impaired. It will not be possible to secure it.

[0102] Adhesive strength is 250-2000g/15mm
To achieve the desired width, the composition, thickness, and surface treatment of the adhesive are controlled.

The packaging material for photographic light-sensitive materials of the present invention can be used for, for example, 35 mm cartridge-packed photographic film, Brownie film, K-16 film, K-35 film, disc film, film unit with lens, and packaging for loading in bright room (e.g. For sealed packaging (pillow packaging, gusset bags, flat bags), etc. (pillow packaging, gusset bags, flat bags, etc.) etc.). In addition, display packaging (for example, film unit with lens “Utsurun Desu Hi”)
It can also be used for “Utsurun desu flash”, “Utsurun desu panorama”, etc.).

[0104] The packaging bag for photographic light-sensitive materials of the present invention is produced by making bags using the above-mentioned packaging material for photographic light-sensitive materials by a heat sealing method, and applying an easy-opening process to the heat-sealed portion of the packaging bag in the direction where the tear strength is low. has been done.

[0105] Easy-to-open processing includes notches, cutting lines,
V-notches, weakened lines, perforations, opening cuts, jagged seals, etc. are used.

[0106] The packaging bags for photographic materials may be of various types, such as single-layer flat bags, double-layer flat bags, single-layer gusset bags, and double-layer gusset bags. The bag can be made by conventionally known plastic film bonding methods such as hot plate bonding, impulse bonding, fusing bonding, ultrasonic bonding, and high frequency bonding. In addition, it is also possible to make bags by an adhesive method using an adhesive, an adhesive method using a pressure-sensitive adhesive, or an adhesive method using a pressure-sensitive or heat-sensitive adhesive.

[0107]

[Function] In the packaging material for photographic materials of the present invention, the outer layer made of biaxially oriented thermoplastic resin film or cellophane ensures heat resistance, easy opening, dust-free property, and physical strength, and has a white, yellow, silver color or When made translucent, it improves printability, appearance, and ability to distinguish between front and back under safelight.

[0108] The polyolefin resin film layer ensures physical strength, heat sealability, antistatic property, moisture proof property, gas barrier property, light shielding property, sealing property, etc.

[0109] When the metal layer ensures moisture resistance, gas barrier properties, and easy opening, and when the outer layer is white, yellow, silver, or translucent, it has an appearance with high commercial value, and even under safelight, the presence and the front and back are invisible. The packaging material is easy to identify and has excellent workability.

[0110] In addition, polymide resin films, ethylene vinyl alcohol copolymer resin films, or polyacrylonitrile resin films improve gas barrier properties, especially oxygen barrier properties that degrade the quality of photographic light-sensitive materials, and provide excellent physical strength. ing.

In particular, a multilayer coextruded film coextruded simultaneously with the polyolefin resin film of the inner layer is an inexpensive packaging material with excellent physical strength, oxygen barrier properties, heat sealability, etc.

[0112]

[Example] Examples of the packaging material for photographic materials according to the present invention will be explained based on the drawings. 1 to 3 are partial cross-sectional views showing the layer structure of a packaging material for photographic light-sensitive materials. In the packaging material for photographic materials shown in FIG. 1, an outer layer 2 made of a biaxially oriented thermoplastic resin film is laminated on one side of an intermediate layer 1 made of metal foil with an adhesive layer 3 interposed therebetween, and an An inner layer 4a made of an unstretched polyolefin resin film to which a light-shielding substance has been added is laminated with an adhesive layer 3 interposed therebetween.

The packaging material for photographic materials shown in FIG. 2 has a biaxially stretched thermoplastic resin on the side of the metal thin film 6 of the intermediate layer 1 which is made of a metal thin film processed flexible sheet in which a metal thin film 6 is processed on the flexible sheet layer 5. Outer layer 2 consisting of film
are laminated with an adhesive layer 3 interposed therebetween, and an inner layer 4a made of a uniaxially oriented polyolefin resin film to which a light-shielding substance is added is laminated with an adhesive layer 3 interposed therebetween. ing.

The packaging material for photographic materials shown in FIG. 3 has a biaxially stretched thermoplastic resin film on one side of an intermediate layer 1 made of a polyamide resin film, an ethylene vinyl alcohol copolymer resin film, or a polyacrylonitrile resin film. An outer layer 2 consisting of is laminated via an adhesive layer 3, and an inner layer 4a consisting of a uniaxially oriented polyolefin resin film to which a light blocking substance is added is laminated via an adhesive layer 3 on the other side. There is.

FIG. 4 is a plan view of an embodiment of a packaging bag for photographic materials made from the packaging material for photographic materials of the present invention.

The packaging bag for photographic material shown in FIG. 4 is heat-sealed around the periphery to form a heat-sealed sealing portion 11, in which a photographic material 12 is housed. Furthermore, triangular notches 13 are continuously formed on both ends to facilitate opening.

Example 1 A packaging material for photographic materials having a layer structure corresponding to the partial sectional view shown in FIG. 1.

[0118] The outer layer is a biaxially stretched polyester resin film with a thickness of 12 μm, the middle layer is a soft aluminum foil with a thickness of 9 μm (matte side facing the outer layer), and the inner layer has an MI of 10 g/10.
Ethylene butene with a density of 0.920 g/cm3
1 copolymer resin (C4 L-LDPE resin) 50% by weight
and MI is 0.5g/10min, density is 0.954g/cm
29.55% by weight of high-density homopolyethylene resin polymerized by a low-pressure method using the Ziegler catalyst of No. 3, 5% by weight of oil furnace carbon black, 0.1% by weight of nonionic surfactant (monoglyceride type antistatic agent) , 5.8 Dimenthyl-tocotrie
A polyolefin resin composition consisting of 0.15% by weight of nol, 0.2% by weight of dimethylpolysiloxane having a viscosity of 20,000 centistokes, and 15% by weight of an unsaturated carboxylic acid graft polymerized polyolefin adhesive resin (Novatec AP manufactured by Mitsubishi Kasei). A light-shielding polyolefin resin film with a thickness of 50 μm was produced using an inflation film molding machine at a blow ratio of 1.2. The outer layer and the middle layer, the middle layer and the inner layer are both 20 μm thick, and the MI is 20 g/10 minutes.
30% by weight of ethylene-butene-1 copolymer resin with a density of 0.921 g/cm3, 59.7% by weight of high-pressure low-density homopolyethylene resin with an MI of 5.18 g/10 min and a density of 0.919 g/cm3. , unsaturated carboxylic acid graft polymerization adhesive resin (Novatec AP manufactured by Mitsubishi Kasei) 10% by weight
, 5.8 Dimenthyl-tocotrieno
A polyolefin resin composition consisting of 0.2% by weight of L and 0.1% by weight of synthetic silica was laminated using an extrusion laminator via an adhesive layer coated by hot melt extrusion. The two adhesive layers were applied by hot melt extrusion using a tandem laminator in the same process (extrusion lamination speed: 100 m/min). Inside the outer layer (
The surface (aluminum foil side) was subjected to corona discharge treatment, and the intermediate layer aluminum foil was presheeted with a heated roller at 100°C to improve the adhesive strength with each hot-melt extrusion coating layer.

[0119] The adhesive strength between the outer layer and the middle layer is 675g/15
mm width, and the adhesive strength between the middle layer and the inner layer is 482g/1
It was 5mm wide.

Using this packaging material, a light-shielding bag for a sheet-like photographic material as shown in FIG. 4 was prepared with the inner layer as a heat-sealing layer. This completely sealed light-shielding bag makes it easy to distinguish between the front and back and the presence of the package even under the safe light used to process and package photographic materials, and can be easily torn by hand. It also had excellent dust resistance. Furthermore, we were able to provide a light-shielding bag that has a luxurious appearance with less glare even under sunlight and has the effect of making it difficult to see scratches and irregularities caused by foreign matter (clumps of insoluble matter, etc.) in the laminated film.

[0121] Large light blocking ability (5.8 Diment
hyl-tocotrienol, dimethylsiloxane addition effect), the inner layer was able to be obtained while reducing the screw load and reducing the generation of insoluble matter due to resin burning.

By adding 10% by weight or more of ethylene copolymer resin to the inner layer, it is possible to compensate for the deterioration in heat sealability caused by adding one or more of lubricants and conductive substances. In particular, a packaging material that can ensure long-term sealing performance can be provided. This laminated film uses an ethylene/α-olefin copolymer resin with high tear strength, but by laminating the film with an adhesive strength of 250 g/15 mm or more, it can be made into a packaging material that can be torn by hand.

[0123] It has a beautiful appearance with little negative impact on photographic performance and has great commercial value (the matte surface of soft aluminum is placed on the outer layer side, a blend of three types of resin is used for the adhesive layer of the outer layer and the intermediate layer, and the thin 5.8 of antioxidants that add color
Effects of using a resin composition containing dimentyl-tocotrienol and synthetic silica) This is a packaging material.

Example 2 The outer layer was aluminum vapor-deposited with a thickness of 30 μm (deposition thickness of 40 μm).
0Å, vertically uniaxially stretched high-density polyethylene resin film,
The middle layer is an unstretched ethylene vinyl alcohol copolymer resin film with a thickness of 30 μm, and the inner layer has an MI of 2.1 g/10.
Ethylene butene with a density of 0.920 g/cm3
1 copolymer resin 60% by weight, MI 2.0g/10min,
10% by weight of low-pressure homopolyethylene resin with a density of 0.945 g/cm3, an MI of 2.4 g/10 min, and a density of 0.
923 g/cm3 high pressure homopolyethylene resin 24.
55% by weight, 5% by weight of oil furnace carbon black, 0.2% by weight of dimethylpolysiloxane with a viscosity of 10,000 centistokes, 0.1% by weight of phenolic antioxidant, 0.05% by weight of synthetic silica, nonionic This is a polyolefin resin film containing 0.1% by weight of a surfactant (Electro Stripper TS manufactured by Kao Soap). MI with a thickness of 20 μm for the outer layer and the middle layer, and the middle layer and the inner layer.
is 6.3 g/10 minutes, 80% by weight of high-pressure homopolyethylene resin with a density of 0.920 g/cm3, 1% by weight of titanium oxide, 5.8 Dimenthyl-tocotrie
(Tandem laminate in the same process) (The resin temperature was 315°C).

[0125] The adhesive strength between the outer layer and the middle layer is 547g/15
mm width, and the adhesive strength between the middle layer and the inner layer is 893g/1
It was 5mm wide.

Using this packaging material, a light-shielding bag for a sheet-like photographic material as shown in FIG. 4 was prepared. This completely sealed light-shielding bag makes it easy to distinguish between the front and back and the presence of the package even under the safe light used to process and package photographic materials, and can be easily torn by hand. We were able to provide a light-shielding bag that has excellent dust-proofing properties, moisture-proofing properties, oxygen barrier properties, light-shielding properties, and Gelbo test strength, and maintains photographic performance.

[0127] Great light shielding ability (5.8 Diment
hyl-tocotrienol, dimethylsiloxane addition effect), the inner layer was able to be obtained while reducing the screw load and reducing the generation of insoluble matter due to resin burning.

By adding 10% by weight or more of ethylene copolymer resin to the inner layer, it is possible to compensate for the deterioration in heat sealability caused by adding one or more of lubricants and conductive substances. In particular, a packaging material that can ensure long-term sealing performance can be provided. This laminated film uses an ethylene/α-olefin copolymer resin with high tear strength, but by laminating the film with an adhesive strength of 250 g/15 mm or more, it can be made into a packaging material that can be torn by hand.

[0129]

Effects of the Invention The present invention can improve heat-sealability, moisture-proofing properties, oxygen barrier properties, dust-proofing properties, etc. while maintaining good tearability.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional view showing the layer structure of the packaging material for photographic materials of the present invention.

FIG. 2 is a partial cross-sectional view showing the layer structure of the packaging material for photographic materials of the present invention.

FIG. 3 is a partial cross-sectional view showing the layer structure of the packaging material for photographic materials of the present invention.

FIG. 4 is a plan view of a packaging bag made from the packaging material for photographic materials of the present invention.

[Explanation of symbols]

1...middle class 2...Outer layer 3...Adhesive layer 4...Inner layer 5...Flexible sheet layer 6...Metal thin film 12...Photographic material 13...Notch

Claims (7)

[Claims] Claim 1: A polyolefin system comprising an outer layer made of a biaxially oriented thermoplastic resin film or cellophane, an intermediate layer made of a metal layer, one or more of a lubricant and a conductive substance, and 10% by weight or more of an ethylene copolymer resin. It has an inner layer made of resin film, and the adhesive strength between each layer is 250 to 2.
Packaging material for photographic materials characterized by having a width of 000g/15mm 2. An outer layer made of a biaxially oriented thermoplastic resin film or cellophane, an intermediate layer made of a polyamide resin film, an ethylene vinyl alcohol copolymer resin film, or a polyacrylonitrile resin film, and one or more of a lubricant and a conductive substance. and an inner layer made of a polyolefin resin film containing 10% by weight or more of ethylene copolymer resin, and the adhesive strength between each layer is 250 to 2000 g/15 mm width. 3. The packaging material for photographic materials according to claim 1 or 2, wherein the inner layer has molecules oriented in a uniaxial direction. 4. The outer layer and the intermediate layer, and the intermediate layer and the inner layer are bonded together with a solution type adhesive layer made of a polyester resin or a polyether resin having an isocyanate group at the end.
Packaging materials for photographic materials described in 5. The outer layer and the intermediate layer and the intermediate layer and the inner layer are bonded together with a polyolefin resin extrusion laminate adhesive layer containing 5 to 40% by weight of an adhesive resin. Packaging materials for photographic materials
6. The packaging material for photographic materials according to claim 1 or 2, wherein the outer layer is white, yellow, silver, or translucent. 7. The packaging material for photographic material according to claim 1, 2, 3, 4, 5 or 6 is made into a bag by a heat sealing method, and the packaging bag is heat-sealed in a direction where the tear strength is low. A packaging bag for photographic materials characterized by easy-opening processing on the edges.