JPS6330842A - Packaging material for photographic sensitive material - Google Patents

Abstract

PURPOSE:To obtain an optimum packaging material sufficient in physical strength in spite of its thinness, light shading ability, antistaticness, moisture proofness, or the like for packing a photographic sensitive material by laminating a light-shading polyolefin resin type monoaxially molecule-oriented film layer on the aluminum side of an aluminum vapor-deposited monoaxially oriented thermoplastic resin film layer with an adhesive layer between them so as to cross both molecular orientation axes with each other. CONSTITUTION:The monoaxially molecule-oriented thermoplastic resin film layer 1 and the 5.5-120nm thick aluminum layer 2 vapor-deposited on said film layer 1 constitute a 7-70mum thick layer 3, and the light-shading polyolefin resin type monoaxially molecule-oriented film layer 5 containing a >=5wt% polyoethylene copolymer and a 0.1-20wt% light-shading material is laminated on the adhesive layer 4 attached to the aluminum side of the layer 3 so as to cross the molecular orientation axes of the film layers 5 with that of the layer 1, thus permitting the obtained packaging material to be good in tear resistance, impact puncture resistance, tensile strength, light-shading performance, moisture proofness, slidability, heat-seal aptitude, and the like even in the case of using a thin film.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a packaging material suitable for photographic materials.

[Conventional technology]

Various types of packaging materials for photographic materials are in widespread use, and various performances are required depending on the intended use.

Packaging materials that completely block light are used as packaging materials for photographic materials that lose their commercial value when exposed to light. In this case, the required properties include packaging material slit suitability, gas barrier properties, light shielding properties, moisture proofing properties, rigidity, physical strength (breaking strength, tear strength, impact puncturing strength, gelbo test strength, abrasion strength, etc.), and heat seal suitability ( heat sealing strength, cut sealing properties, hot tack properties, contaminant sealing properties, etc.), antistatic properties, flatness, sliding properties, etc.
Can be mentioned. Conventionally, as shown in Fig. 13, a single-layer film of a very thick high-pressure branched low-density polyethylene (hereinafter referred to as LDPE) resin light-shielding film layer 15a kneaded with carbon black, pigments, etc. Composite laminate films of light-shielding films and flexible sheet layers such as paper, aluminum foil, and cellophane have been used.

An example of a composite laminate film is shown in FIG. 14, which is used in products that particularly require moisture resistance.A metal foil layer 16 is attached to an LDPE resin light-shielding film layer 15a via an adhesive layer 4. They are laminated together, and a flexible sheet layer 6 is further laminated with an adhesive layer 4 interposed therebetween.

FIG. 15 is a partial sectional view of a packaging material used as the inner paper of a double gusset bag for color photographic paper. This packaging material is particularly required to have physical strength, and as shown in FIG.
It has a layered structure in which LDPE resin light-shielding film layers 15 are laminated.

In addition, there are packaging materials shown in FIGS. 16 and 17 that have improved physical strength by combining -axis stretched films. The packaging material shown in FIG. 16 has a layered structure in which uniaxially stretched thermoplastic light-shielding film layers 17 are laminated on both sides of an aluminum foil layer 16 with adhesive layers 4 interposed therebetween so that their stretching directions intersect with each other. The packaging material shown in FIG. 17 has a layered structure in which uniaxially stretched thermoplastic light-shielding film layers 17 are laminated with an adhesive layer 4 so that their stretching directions intersect with each other.

[Problem that the invention seeks to solve]

Although conventional composite laminate films have been constructed to improve the physical properties mentioned above, they still do not have sufficient physical properties, resulting in problems such as tearing or holes during packaging, and peeling of heat-sealed parts. There was a drawback.

Furthermore, adding a large amount of light-shielding substances such as carbon black will significantly deteriorate the physical strength, so the amount added should be around 3%, and the thickness of the film laminated with other flexible sheet layers should be at least 70μ. there were. As a result, the packaging becomes bulky, and the rigidity of the laminate film becomes thick (this results in poor packaging workability and high costs).

For example, in the laminated film shown in Figure 14, the aluminum foil layer is used to provide gas barrier properties, improve moisture resistance, and prevent static electricity.As a result, tear strength, impact puncture strength, gelbo test strength, etc. On the contrary, the problem worsened considerably, and especially when packaging heavy items, the problem of breakage sometimes occurred. For this reason, the thickness of carbon black's LDPE resin light-shielding film has been increased to 70 μm or more, but it still does not have sufficient physical strength, and for example, as shown in Figure 15, the physical strength is insufficient for packaging color photographic paper.
Laminated films of layered constructions have also been used.

In addition, in the case of the packaging material shown in Figure 16, the physical strength such as the degree of tearing is improved to some extent, but as the adhesive layer becomes thicker and the adhesive strength increases, not only does the tear strength decrease, but also the -axial stretching Because it uses a high-density polyethylene film layer, it has poor heat sealability and sometimes causes problems during processing and packaging. In addition, the packaging material shown in Fig. 17, in which the axially stretched thermoplastic resin film layers are directly dipped in a crosswise manner without using aluminum foil, has significantly greater antistatic and moisture-proof properties than a cross-laminated film in which aluminum foil is laminated. Not only was it inferior, but when the product was packaged in a gusset bag, bin holes were generated in the gusset part of the gusset bag, and as a packaging material for photographic light-sensitive materials, it had problems because it had poor light-shielding, moisture-proofing, and gas-barrier properties.

The present invention solves the above-mentioned problems and provides a packaging material that has sufficient physical strength, light-shielding properties, power outage prevention properties, moisture-proofing properties, etc. even though it is thin, and is optimal for packaging photographic materials. purpose.

[Means for solving problems]

The present invention has been made to achieve the above object, and provides a packaging material for photographic light-sensitive materials with a uniaxially molecularly oriented thermoplastic resin film layer and a thickness of 55 to 50 mm. A light-shielding layer comprising an aluminum vacuum-deposited thermoplastic resin film layer with a thickness of 7 to 70 IIm consisting of an aluminum vacuum-deposited layer of 1,200 people, and 5% by weight or more of an ethylene copolymer resin and 0.1-20% by weight of a light-shielding substance. The light-shielding polyolefin resin-based uniaxially molecularly oriented film layer has a polyolefin resin-based uniaxially oriented molecularly oriented film layer, and the molecular orientation axis of the light-shielding polyolefin resin-based uniaxially oriented film layer intersects with the aluminum vacuum-deposited layer side of the aluminum vacuum-deposited film layer. This structure is characterized by being laminated with an adhesive layer in between.

As the uniaxial molecularly oriented thermoplastic resin film layer which forms the aluminum vacuum evaporated thermoplastic resin film layer essential to the present invention, there are various thermoplastic resin films such as various polyethylene films, various polypropylene films, polyester films, and polyamide films. It is a film made of a film, a polycarbonate film, a polystyrene film, a polyvinylidene chloride film, a polyvinyl chloride film, etc., a copolymer containing these as a main component, or a mixture of two or more of these thermoplastic resins. Preferred are polyester film, nylon film, and high density polyethylene film (HDPE).
, medium density polyethylene film (MDPE), low pressure normal low density polyethylene film (L-LDPE)
, polypropylene films, particularly preferred are polyester films, polypropylene films, and films with a density of 0.
．． This is a uniaxially molecularly oriented film made of a high-density polyethylene film of 940 g/co1 or more, and a resin composition in which HDPE resin, L-LDPE resin, and carbon black are mixed.

Uniaxial molecular orientation of a thermoplastic resin film layer with uniaxial molecular orientation is defined as when the molecular orientation rate in the molecular orientation direction is 1.5 times or more higher than the molecular orientation rate in the 90 degree direction, or when the tear strength ratio is 1.5 times or more. This means that it has increased by more than five times.

For example, a blown film that is stretched 3 times in the vertical direction at a blowing ratio of 2 times or a uniaxially molecularly oriented film may be obtained.

In addition, although uniaxially stretched films (horizontal uniaxially stretched film using a tenter, longitudinally-axially stretched film) are commonly used as films with uniaxial molecular orientation, in the present invention, films produced by a known uniaxially molecularly oriented film forming method can be used. For example, in the case of physical shaping or blown film (tubular film), the blowing ratio is increased to orient the molecules, or the molecules are strongly oriented in the longitudinal direction, then cut into a spiral shape and spread out at an angle (for example, 45°). A flat film with molecular orientation is also called a uniaxial molecular orientation film. Examples of known manufacturing methods for uniaxially oriented films (including -axially oriented films) include JP-A-47-34656 and JP-A-47-48-
100464, 59-127725, 59-122
726, Special Public Service No. 40-5319.47-38621.4
7-3992753-18072, υ5P33226
There are 13, etc.

Further, the uniaxial molecularly oriented thermoplastic resin film layer may be formed of two or more layers by coextrusion.

In the case of -axis orientation, the molecular orientation may be vertical, horizontal, or oblique.

A method of vacuum-depositing aluminum onto a uniaxially oriented thermoplastic resin film layer will be described.

Various known heating methods such as electric resistance heating, electron beam heating, and high frequency heating may be used to vacuum deposit aluminum.

The aluminum vacuum-deposited layer preferably has a thickness of 55 to 1,200 mm from the viewpoint of physical strength, light-shielding, antistatic and moisture-proof properties as a laminate, cost, and quality.

That is, if the thickness of the aluminum vacuum deposited layer is less than 55 mm, it is not possible to reduce the electrification generated in the uniaxially molecularly oriented thermoplastic resin film layer and the polyolefin resin uniaxially molecularly oriented film layer on both sides of the aluminum vacuum deposited layer. Unless the thickness of the uniaxially oriented film layer and the light-shielding layer on both sides of the aluminum vacuum-deposited layer is increased, the moisture-proofing properties, physical strength, light-shielding properties, etc. necessary for a packaging material for photosensitive materials cannot be secured.

In addition, if the thickness exceeds 1,200 layers, antistatic, moisture-proof, and light-shielding properties can be ensured, but due to cost and vacuum evaporation methods, the uniaxially oriented thermoplastic resin layer may deteriorate due to heating, heat shrinkage, wrinkles, and the finished laminated layer. There are problems such as a decrease in the physical strength of the film, making it difficult to put it into practical use. The thickness of the aluminum vacuum-deposited layer is preferably 55 Å or more, and for normal use it is preferably 80-800, more preferably 100-600.

If necessary, a protective layer may be provided on the aluminum vacuum-deposited layer.

As a protective layer for the aluminum vacuum deposited layer, acrylic resin, cellulose resin such as acetic acid fiber type, urethane resin, epoxy resin, polyester resin, ionomer resin, E
Appropriate resins such as EA resin, various polyethylene resins, and polypropylene resins can be used. Furthermore, wax, gelatin, polyvinyl alcohol, etc. can also be used. The protective layer of aluminum vacuum-deposited layer is preferably formed to have an extremely thin thickness. Even in the case of extrusion lamination, if the thickness is not 50 μm or less, static electricity will not be removed sufficiently.

When the thickness is reduced to 5 μm or less using a known solution coating method or spray coating method, the aluminum vacuum-deposited layer can be protected and static electricity can be effectively removed. Antistatic agents and metals such as carbon black, aluminum powder, and aluminum paste are used in the protective layer of the flexible sheet layer, uniaxially oriented thermoplastic resin film layer, light-shielding polyolefin resin uniaxially oriented film layer, adhesive layer, and aluminum vacuum-deposited layer. It is also possible to mix conductive substances such as powder and carbon fiber.
In this way, static electricity can be removed even more completely.

The thickness of the aluminum vacuum-deposited thermoplastic resin film layer consisting of the uniaxial molecularly oriented thermoplastic resin film layer and the aluminum vacuum bonding layer is 7 to 70 μm. If the thickness is less than 7 μm, if you try to deposit an aluminum vacuum-deposited layer with a thickness of 55 Å or more, thermal deformation will occur, and wrinkles or cuts will easily occur during the lamination process, causing problems. The cost is high, and the cost of the uniaxially oriented thermoplastic resin film layer is also high, making it difficult to put it into practical use.

Polyolefin resins used for the polyolefin resin uniaxially oriented film layer include (1) low density polyethylene resin (LDPE), and (2) medium.
(Montaba E) (3) High (IIDPE) (4) Linear low density (L-LDPE) (5) Ethylene-propylene copolymer resin (random or block copolymer resin, etc.) (6 ) Ethylene-butene-1 copolymer resin (capropylene 〃 〃 (8) Ethylene-propylene-butene-1 copolymer resin (9) Polybutylene-1 resin α0) Polystyrene resin 0υ Polymethyl methacrylate resin layer Styrene
Acrylonitrile copolymer resin Q'1) ABS resin (141 polypropylene resin Q'J) Crystalline propylene-α-olefin copolymer resin αe Modified polypropylene resin an Polyethylene α (to) Polypropylene/maleic anhydride graft copolymer Resin 0ω Chlorinated polyolefin resin (mainly chlorinated polyethylene resin) (HDPE, LDPE, PE copolymer, acoustic pp, etc.) (2Φ Ethylene-vinyl acetate copolymer (EVA) (2
1) Ethylene-based ionomer resin (resin in which a copolymer of ethylene and unsaturated acid is cross-linked with metal) (22) Poly-4-methylpentene-1 resin (23) Ethylene-acrylic acid copolymer resin (EAA) ( 24) Ethylene/methyl acrylate copolymer resin (to Gate E) (25) Ethylene/ethyl acrylate copolymer resin (E
EA) (26) Vinyl chloride/propylene copolymer resin (27)
Ethylene/vinyl alcohol resin (28) Crosslinked polyethylene resin (electron beam irradiation crosslinking, chemical crosslinking, etc.) (29) Polyisobutylene resin (30) Ethylene-vinyl chloride copolymer resin (31)
(2), 2-polybutadiene resin, etc.

Among various polyolefin resins, the most preferred copolymer of ethylene and α-olefin having 3 to 13 carbon atoms (Line
ar Low Density Poly Ethyi
The resin (hereinafter referred to as L-LDPE after taking the initial letter ene) is called the third polyethylene resin, and is produced using the conventional medium-low pressure method.
It is a low-cost, high-strength resin that combines the advantages of both high-pressure polyethylene resins and meets today's demands for energy and resource conservation.

L-LDPE resins are broadly classified into two types in terms of physical strength.

The first L-LDPE resin is a copolymer resin of ethylene and butene-1 having 4 carbon atoms, and has an Ml of 0.2 to Log/10.
A typical example of ethylene with a density of 0.87 to 0.94 g/c is produced by a low-pressure, gas-phase reaction in the presence of a highly active catalyst called the Unipol process developed by Union Carbide in the United States. It is a copolymer resin.

This L-LDPE resin was manufactured using a conventional high-pressure process (300
Compared to branched low-density polyethylene resin (hereinafter referred to as LDPE) produced by LDPE (0 atm, 300°C), it has a narrower molecular weight distribution and is linear. Since it is an energy-saving process product, it is inexpensive, has good hot duck properties and impurity sealing properties, and has excellent cold resistance with little loss of heat seal strength at low temperatures and over time. In terms of strength, there are problems in that the molecular orientation in the vertical direction is more likely than in the molecular structure, and the strength of tearing in the vertical direction is small. However, the present invention is preferably used as a heat seal layer with longitudinally uniaxial molecular orientation. Manufacturing methods other than the gas phase method include a liquid phase method and a high pressure modification method using ionic polymerization.

The specific product names and manufacturing methods are vapor phase method...G resin or Uniball (U CC), N
UC polyethylene-LL (Nippon Unicar), iso-liquid phase method...Idemitsu polyethylene L (Idemitsu Petrochemical), Nippon Oil Chemicals (Nippon Petrochemical), Souffle (DuPont Canada), iso-high pressure method (ionic polymerization) ...Rotrex (CDFch
imie) etc.

The second L-LDPE resin has a melt index of 0.
Density is 0.870-0.940 at 5-10g/10 minutes
g/CII! and 4-methylpentene-1 or hexene-1 having 6 carbon atoms in ethylene or 8 carbon atoms
It is a copolymer of octene-1.

As a resin made by copolymerizing 4-methylpentene-1, which has 6 carbon atoms, and ethylene, there is Urtozex, which is made by Mikata Petrochemical's solution method, and as a resin made by copolymerizing hexene-1 and ethylene, there is Examples include TUFLIN, a gas-phase method manufactured by Union Carbide.

Examples of resins made by copolymerizing octene-1, which is an α-olefin having 8 carbon atoms, and ethylene include Stamilesox, a liquid-phase method produced by DSM-Stamicarbon Co., Ltd., and Dowlex, a liquid-phase method produced by Dow Chemical Company.

Although the same L-LDPE resin is used, L-LDP is made by copolymerizing butene-1 with 4 carbon atoms as an α-olefin with ethylene.
E resin is 20% cheaper than L-LDPE resin, which is made by copolymerizing 4-methylpentene-1, hexene-1, and octene-1 with 6 or more carbon atoms as α-olefins with ethylene.
Although they are inexpensive, the tear strength is lower than 172.They are completely different resins, and even when used as a blend, the mixing ratio, grade, etc. must be kept within a limited range, otherwise they cannot be used as packaging materials for photographic materials. The laminated film becomes unusable.

The polyolefin resin uniaxially oriented film layer contains 5% by weight or more of ethylene copolymer resin. This ethylene copolymer resin includes L-LDPE resin, EV
These include A resin, EEA resin, EMA resin, and EAA resin.

Among these resins, the most preferable ethylene copolymer resin is that it increases physical strength such as tear strength and gelbo test strength, and even if a light-shielding substance, especially carbon black, is added, conventional LDPE resins and HDPE resins do not have physical strength or heat resistance. While the seal strength decreases, the physical strength and heat seal strength improve.

It is L-LDPE resin.

The above-mentioned ethylene copolymer resin is contained in an amount of 5% by weight or more.

As a result, heat-sealing properties (heat-sealing strength, real tank properties, contaminant sealing properties) are good, tear strength and other physical strengths can be improved, and suitability for mixing with light-shielding properties is improved.

In particular, the light-shielding polyolefin resin-based uniaxial molecularly oriented film layer containing carbon black, which contains L-LDPE resin, has several times the tear strength compared to the light-shielding LDPE resin film layer, and also has a tear strength that is several times stronger than that of the light-shielding LDPE resin film layer. Good seal strength.

The polyolefin resin-based uniaxially molecularly oriented film layer is laminated such that its molecularly oriented axis intersects the molecularly oriented axis of the uniaxially oriented thermoplastic resin film layer. It is sufficient that these molecular orientation axes intersect, and they can be stacked at any angle such as 90 degrees or 45 degrees.

The uniaxially oriented thermoplastic resin film layer and polyolefin resin uniaxially oriented film layer of the present invention are L-LDPE resins with excellent heat sealability and physical strength, lubricity, rigidity, tensile strength, moisture resistance, and film surface. By blending HDPE resin, which has low strength and is suitable for manufacturing uniaxially molecularly oriented films, it is suitable for manufacturing uniaxially molecularly oriented films, physical strength, heat sealing, moisture proofing, and suitability for adding light shielding substances.
We investigated the slip characteristics, etc.

In this way, compared to the axial molecularly oriented film produced only with HDPE resin, in particular, 50 to 90% by weight of HDPE resin,
IIDPE- containing 10-50% by weight of L-LDPE resin
The axially oriented film produced using the L-LDPE resin composition not only greatly increases the possibility of adding light-shielding substances, but also improves heat-sealability (heat-seal adhesion width expands, heat-seal strength, hot tack property, and contaminants). Improved sealing performance and increased heat sealing strength even at low temperatures), physical strength (improved tear strength, impact drilling strength, and Gelbo test strength), and processing machine suitability (improved heat-resistant flexible sheets such as aluminum foil and paper with uniaxial molecular If it is not laminated between the oriented films, the axial molecular oriented film made with only II DPE resin will have various characteristics such as pinholes (the problem could not be solved) even if the shape of the heat sealer was changed in various ways. Significantly improved.

In particular, a polyolefin resin-based uniaxially oriented film layer to which a powdery light-shielding substance such as carbon black is added has a particularly large improvement effect on film manufacturing suitability, film physical strength, light-shielding properties, etc. LDP [! When carbon black is blended with a resin or HDPE resin, the physical strength is significantly reduced, and the film cannot be put into practical use unless the film thickness is increased. HDPE consisting of HOPE resin with special addition of carbon black
When the amount of carbon black added to the uniaxially oriented film layer increases, not only does the physical strength decrease, but also the occurrence of fish knots increases.The amount of carbon black added that can be stably produced even if the stretching ratio is less than 2 times is 7% by weight or less. When the stretching ratio is 6 times or more, the amount of carbon black that can be stably produced is 2% by weight or less, and it is necessary to increase the thickness of the film to ensure light-shielding properties with only a uniaxially oriented film. In contrast, L-HDPE resin
~90% by weight, HDPE-L-LDPE resin composition containing 10~50% by weight of L-LDPE resin -Axis molecular oriented film can be stably manufactured using HDPE resin with carbon black addition amount of 10~50% by weight. 1, about twice as much as if
It is 5 times ■%.

In particular, HD containing 30% by weight or more of L-LDPE resin.
In the case of a PEL-LDPE resin composition, the addition of carbon black greatly improves the tear strength, impact puncture strength, etc., and the strength also improves as the amount of carbon black added increases up to about 7% by weight. Since both light shielding properties and physical strength are improved at the same time, it is possible to reduce the thickness of the uniaxially oriented film layer, which not only improves suitability for heat sealing and processing machines, but also reduces the appearance and storage costs of packaging materials. Packaging costs can be significantly reduced due to savings and reduced raw material costs. In particular, when the resin contains 50% by weight of L-LDPE resin, up to 20% by weight of the light shielding substance can be added.

The light-shielding substance, which is a preferable component of the light-shielding polyolefin resin-based uniaxially oriented film layer, is one that can be mixed and dispersed in the polyolefin resin and does not transmit visible light sources, ultraviolet rays, and the like.

Light-shielding substances that can be used in the present invention include various carbon blacks, iron oxide, zinc white, titanium oxide, clay aluminum powder, aluminum paste, calcium carbonate, mica, barium sulfate, talc cadmium pigments, yellow lead, and Bengara. , cobalt blue, phthalocyanine pigments, monoazo or polyazo pigments, aniline black, and other organic pigments and inorganic pigments.

Among these light-shielding substances, in terms of quality, cost, light-shielding ability, etc., those with lower volatile substances removed are better than colored pigments that easily absorb or reflect light, especially various types of black pigments such as carbon black, aluminum powder, and aluminum paste. preferable.

Among carbon blacks, furnace carbon black is preferable, and as light-shielding substances that are expensive but have antistatic effects, acetylene carbon black, Ketjen carbon black, graphite, etc. are preferable.If necessary, two or more types of light-shielding substances may be used. It is also preferable to mix according to the following. On the other hand, among these carbon bras, those with a pH of 15 to 9 and an average particle size of 10 to 120 mμ are preferable, particularly those with a pH of 6 to 9 and an average particle size of 15 to 30 mμ.
μm furnace carbon black is preferred.

By using a material having such a pH and particle size, fogging is less likely to occur. A polyolefin resin-based uniaxial molecularly oriented film with little increase or decrease in photosensitivity and high light shielding ability. Even when added to a uniaxially oriented L-LDPE film, for example, pinholes due to carbon black lumps and fissoyuai will not occur. Packaging materials can be obtained that have a number of advantages, such as low resistance.

The above-mentioned aluminum paste is a paste-like material that is formed into a paste in the presence of mineral spirit and a small amount of higher fatty acids such as stearic acid or oleic acid when making aluminum powder by a known method such as a ball mill method, a stamp mill method, or an atomization method. It was made in. In the present invention, this aluminum paste and polyolefin thermoplastic resins (various polypropylene resins, various polyethylene resins, EVA resins, EEA resins, EAA resins, etc.) are heated and kneaded, and low-volatile substances (mainly mineral spirits with a strong odor) are pumped using a vacuum pump. The material removed by etc. is used as aluminum paste compound resin, aluminum paste master bar Noah resin.

In particular, it is used as an aluminum paste master bunch resin in order to eliminate harmful effects and bad odors on photographic light-sensitive materials, and also has light-shielding properties, and the content of mineral spirits in the polyolefin resin uniaxially oriented film layer is 0.1% by weight or less. It is also preferable to

For example, mineral spirits in a masterbatch resin with an aluminum paste content of 40% by weight, 7 months, 0
Even if the aluminum paste concentration is 2% by weight in the light-shielding polyolefin resin uniaxially oriented film layer, 19 parts by weight of natural polyolefin resin per 1 part by weight of aluminum paste masterbatch. Since some of the mineral spirit in the light-shielding polyolefin resin uniaxially oriented film layer is removed as gas during film formation, the mineral spirit content is 0.05% by weight or less. As a result, there is no adverse effect on the photographic material, and odor is also reduced.

Aluminum powder can be made by pulverizing molten aluminum into powder by atomizing, granulating, rotating disk dropping, evaporating, etc., or by crushing aluminum foil into flakes by ball milling, stamp milling, etc. Including things. Fluminiram powder alone is unstable, so various known treatments are applied to make the surface of the aluminum powder inert. Known metal flake manufacturing methods include USP 4,4
69.282, Tokuko Sho 37-6779, Tokuko Sho 46-6
713, etc., and JP-A-59-75931, etc. as a method for producing metal powder for filling synthetic resin.

The amount of the above-mentioned light-shielding substance added to the light-shielding polyolefin resin uniaxially oriented film layer is 0.1 to 20% by weight.
It is.

The effect of carbon black blending is clearly visible at 0.1% by weight and becomes more pronounced when it exceeds 3% by weight, but as the blending amount is further increased, the occurrence of lumps increases and costs increase. If it exceeds 20% by weight, the occurrence of lumps due to poor dispersion of carbon black will increase, moisture permeability will increase, and pinholes will cause problems in terms of poor light-shielding properties.

Moreover, the cost is also relatively high. As packaging materials for photographic materials, hygroscopicity, flatness, film surface strength, heat sealability, contamination of photographic materials, etc. are also issues, so when deciding on the amount of carbon black to be added, economic efficiency, occurrence of bumps, tear strength, etc. are also taken into consideration. Then, it is 0.1 to 20% by weight, preferably 3 to 20% by weight.
It is 7% by weight.

Methods for blending these light-shielding substances into polyolefin resins include the master bunch coloring method, dry color coloring method, compound coloring method, and the like, which have been commonly used in the past.

As mentioned above, there are various methods of blending the light-shielding substance into the polyolefin resin, but the mustard bar-edge method is preferable from the viewpoint of cost, prevention of contamination of the workplace, and the like.

A publicly known document, Japanese Patent Publication No. 40-26196, 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. The publication describes a method for preparing a master bunch by dispersing carbon black in polyethylene.

Adhesives used for the adhesive layer that bonds the aluminum vacuum-deposited thermoplastic film layer and the polyolefin resin-based film layer with the same axis molecular arrangement include various polyethylene resins,
Polyolefin thermoplastic resin hot melt adhesives such as various polypropylene resins, ethylene copolymer resins such as ethylene-propylene copolymer resins, ethylene-vinyl acetate copolymer resins, ethylene-ethyl acrylate copolymer resins, ethylene -There are thermoplastic resin hot-melt adhesives such as acrylic acid copolymer resins and ionomer resins, and other hot-melt rubber-based thermal adhesives.As solution adhesives, there are wet laminating adhesives, emulsions, and latexes. It is a type of adhesive. Typical examples of emulsion adhesives include polyvinyl acetate, vinyl acetate-ethylene copolymer, vinyl acetate and acrylic ester copolymer, vinyl acetate and maleate ester copolymer, acrylic copolymer, and ethylene-acrylic acid. There are emulsions such as copolymers. Typical examples of latex adhesives include natural rubber, styrene butadiene (SBR), and acrylonitrile butidiene (
There are rubber latexes such as NBR) and chloroprene (CR). Adhesives for dry lamination include isocyanate adhesives and urethane adhesives, as well as blends of paraffin wax, microcrystalline wax, ethylene-vinyl acetate copolymer resin, ethylene-ethyl acrylate copolymer resin, etc. Known adhesives such as hot melt laminating adhesives, pressure sensitive adhesives, heat sensitive adhesives, etc. can be used. More specifically, polyolefin adhesives for extrusion include polymers made of polyolefin resins such as various polyethylene resins, polypropylene resins, polybutylene resins, and L-LDPE resins other than ethylene copolymer (EVA, EEA, etc.) resins. Some other monomers (α-olefins) are added to ethylene, such as
Copolymerized ionomer resins such as Dupon Co.'s Surlyn, Mikata Polychemical Co., Ltd.'s Hylamin, etc.
(ionic copolymer) and Mikata Petrochemical's Atomer (adhesive polymer).

The product is easily inserted into the uniaxially oriented thermoplastic resin film layer and the light-shielding polyolefin resin uniaxially oriented film layer (in order to prevent histology and improve film formability, the amount of lubricant should be 1100pp to 1.5% by weight or less). Particularly preferred are dimethylpolysiloxane lubricants and fatty acid amide lubricants (oleic acid amide, erucic acid amide, stearic acid amide, ethyl acid amide, etc.), which are lubricants that make the camera and materials easy to slide without adversely affecting the camera and materials. Particularly preferred is Kao Soap Electro Stripper, which has antistatic and antistatic effects.

Moreover, in addition to the above-mentioned lubricants, various additives can be added in required amounts as necessary.

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

(Additive types) (Representative examples) (1) Plasticizers: phthalate esters, glycol esters, fatty acid esters, phosphate esters, etc. (2) Stabilizers: lead-based, cadmium-based, zinc-based, alkaline earth metal-based , organic tin type, etc. (3) Antistatic agent; cationic activator, anionic activator,
Nonionic activators, bifacial activators, etc. (4) Flame retardants; phosphate esters, halogenated phosphate esters, halides, inorganic substances, phosphorus-containing polyols, etc. (5) Fillers: alumina, kaolin clay, calcium carbonate, mica, talc , titanium oxide, silica, etc. (6) Reinforcing agents; glass roving, metal fibers, glass fibers, glass milled fibers, carbonated fibers, etc. (7) Coloring agents; Inorganic pigments (A I! + Fe zo
(3 + TiOz + ZnO + CdS, etc.), organic pigments (carbon), dyes, etc. (8) Blowing agents; inorganic blowing agents (ammonia carbonate, sodium bicarbonate), organic blowing agents (thoron type, azo type), etc. (9) Vulcanizing agents, vulcanization accelerators, accelerating aids, etc. aω Deterioration inhibitors; UV absorbers, antioxidants, metal deactivators, peroxide decomposers, etc. 00 Camping agents: Silane-based, titanate-based, chromium type, aluminum type, etc.@ Various thermoplastic resins, rubber, etc. Aluminum vacuum vapor deposited thermoplastic resin film layer or light-shielding polyolefin resin type uniaxially oriented film layer with other film layers such as flexible sheet layer and heat seal layer on the outside. It may be laminated.

Other flexible sealing layers used in composite films include thermoplastic resin films such as various polyethylene resins, ethylene copolymer resins, polypropylene resins,
There are known films of polyvinyl chloride resin, polyvinylidene chloride resin, polyamide resin, polycarbonate resin, polyester resin, and films of modified resins thereof.

In addition, metal thin film processing films (typically aluminum vacuum-deposited films), cellulose acetate films, cellophane, polyvinyl alcohol films, various papers, various metal foils (typically aluminum foils),
Non-woven fabric, warif, perforated alkylene film and polyethylene,
Known flexible sheet layers such as foamed sheets of polystyrene, polyurethane, etc. are also suitable.

[For production]

The packaging material for photographic light-sensitive materials of the present invention has essential moisture-proofing properties, antistatic properties, tear strength, impact puncturing strength, gelbo test strength, real tack properties, low-temperature heat-sealing properties, heat-sealing properties, and It has improved drop strength, light blocking properties, contaminant sealing properties, processing machine suitability, bag making suitability, etc.

〔Example〕

An embodiment of the packaging material for photographic materials according to the present invention will be explained based on FIGS. 1 to 9, respectively.

1 to 9 are partial cross-sectional views of packaging materials for photographic materials, respectively.

The embodiment shown in FIG. 1 is an aluminum vacuum-deposited thermoplastic resin consisting of a uniaxially molecularly oriented thermoplastic resin film layer 1a having a light shielding property and an aluminum vacuum evaporated layer 2 formed on the uniaxially molecularly oriented thermoplastic resin film layer 1. It is constructed by laminating a light-shielding polyolefin resin-based uniaxially oriented film layer 5a on a film layer 3a via an adhesive layer 4.

The embodiment shown in FIG. 2 is constructed by laminating the same structure as the embodiment shown in FIG. 1 using an adhesive layer 4a having a light-shielding property.

The embodiment shown in FIG. 3 is constructed by laminating uniaxially oriented thermoplastic resin film layers 1 that do not have light shielding properties in the embodiment shown in FIG.

The embodiment shown in FIG. 4 is constructed by laminating a flexible sheet layer 6 on the light-shielding uniaxially oriented thermoplastic resin film N1 of the embodiment shown in FIG. 1 via an adhesive N4.

The embodiment shown in FIG. 5 is constructed by directly laminating a heat-sealing layer 7 on the light-shielding polyolefin resin uniaxially oriented film layer 5 of the embodiment shown in FIG.

The embodiment shown in FIG. 6 differs from the embodiment shown in FIG. 1 in that an aluminum vacuum-deposited layer 2 is formed on the light-shielding polyolefin resin-based uniaxially oriented film layer 5, and this aluminum vacuum-deposited layer 2 is bonded with an adhesive layer 4. It is constructed by laminating light-shielding polyolefin resin-based uniaxially oriented film layers 5.

The embodiment shown in FIG. 7 is constructed by laminating a heat-sealing layer 7 via an adhesive layer 4 on the light-shielding polyolefin resin-based uniaxially oriented film layer 5 of the embodiment shown in FIG.

The embodiment shown in FIG. 8 is the same as that of the embodiment shown in FIG. The polyolefin resin-based uniaxially oriented film layer 5 is formed by co-extrusion of two layers, and the first light-shielding polyolefin resin-based uniaxially oriented film layer 5
It is formed of two layers by co-extrusion of a and a second light-shielding polyolefin resin-based uniaxially oriented film i5b.

The embodiment shown in FIG. 9 is similar to the embodiment shown in FIG.
It is formed of two layers by co-extrusion of a and a second light-shielding polyolefin resin-based uniaxially oriented film layer 5b.

FIGS. 10 and 11 show examples of packaging bags using the packaging material according to the present invention.

FIG. 10 is a partial sectional view of a double bag in which a photographic material 9 is sealed. A tape 13 is attached. As shown in the partial cross-sectional view of FIG. 12, the outer paper 10 is made of a packaging material consisting of two layers, a flexible sheet N6 and a heat-sealing layer 7, and the inner paper 11 is one of the packaging materials according to the present invention. It is made of the packaging material shown in FIG. 1, which is an example.

Figure 11 shows photographic paper, movie film, printing film,
1 is a conceptual cross-sectional view of a packaging bag for packaging black-and-white or color call-like photosensitive materials such as indirect film and microfilm; FIG. This packaging bag consists of an outer paper 10 and an inner paper 11, both ends of which are folded in, one of which is adhered with an adhesive 12, and the other with an adhesive tape 13.

The packaging material according to the present invention is used for the inner paper 11.

Although the above-mentioned examples have shown preferred representative examples of the packaging material for photographic light-sensitive materials of the present invention, the present invention is not limited thereto, and combinations with other known materials and flexible sheet layers are possible. is possible.

Next, the results of an experiment comparing the characteristics of a product of the present invention, a conventional product, and a comparative product will be explained.

Inventive product 1 is an L-LDPE resin made by Mikata Petrochemical Co., Ltd., which contains 5% by weight of oil furnace carbon black and whose 2-olefin is 4-methylpentene 1 having 6 carbon atoms (C6), which corresponds to the example shown in FIG. (Urtzex 202OL)
HDP of 25% by weight and density 0.964 g/crl
E resin (HIZESOX 5300S) 70% by weight thickness 35. A uniaxially oriented thermoplastic resin film layer 1 and a light-shielding polyolefin resin uniaxially oriented film layer 5 were formed using a diagonally uniaxially oriented film based on HDPH-L-LDPE mixed resin of crm. Then, an extrusion LD with a thickness of 10 μm is placed so that the molecular orientation axes intersect at 90 degrees.
It was laminated with a PE resin adhesive layer 4.

In addition, the thickness of the aluminum vacuum-deposited layer 2 is 400,
The total thickness of the packaging material is 80A1ffl.

The product 2 of the present invention corresponds to the example shown in FIG. 1, and is made of L-LDPE resin manufactured by DSM (Stamirefx #1046) of the Netherlands with C8 α-olefin (30% by weight) and Mitsui Petrochemical type (density 0.96 g/crl). HDPE-L-LDPE mixed resin with a thickness of 35 μm mixed with 6497% by weight of IDPE resin (HIZEX), 5% by weight of oil furnace carbon black, and 0.03% by weight of oleic acid amide (Armoslip CP) manufactured by Lion Akuzu as a lubricant. A uniaxially oriented thermoplastic resin film layer 1 and a light-shielding polyolefin resin uniaxially oriented film layer 5 were formed using axially oriented molecularly oriented films.

Then, the thickness was 10 μm so that the molecular orientation axis was 90 degrees.
Laminated with extrusion LDPE resin adhesive N4.

In addition, the thickness of the aluminum vacuum-deposited layer 2 is 400,
The total thickness of the packaging material is 80pm.

Product 3 of the present invention corresponds to the embodiment shown in FIG. The light-shielding polyolefin resin-based uniaxially oriented film layer 5 is the product of the present invention 2
This is a longitudinally-axially stretched film having a thickness of 50 μm and having the same resin composition. The uniaxially oriented thermoplastic resin film layer 1 is a horizontally uniaxially stretched high-density polyethylene film (Karalyan film) manufactured by Toyo Kagaku and has a thickness of 18 μm. and thickness 1
A 2 μm extrusion LDPE resin adhesive layer was laminated so that the molecular orientation axes intersected at 15 degrees.

In addition, the thickness of the aluminum vacuum-deposited layer 2 is 400,
The total thickness of the packaging material is 80 μm.

The products of the present invention A, 4B, 4C, and 4D correspond to the embodiment shown in FIG. L-LDPE resin manufactured by DSM (Netherlands) where the 2-olefin is Cs octene-1 (Stamirefx #
1016) 15% by weight and Mikata Petrochemical's density 0.
96g/clll IDPE resin (Hizesox) 80
．． 4% by weight, oil furnace carbon black 4.5
% by weight, thickness 3 mixed with 0.1% by weight of oleic acid amide (Armos Resop CP) manufactured by Lion Akzo as a lubricant.
A uniaxially oriented thermoplastic resin film layer 1 and a light-shielding polyolefin resin uniaxially oriented film layer 5 were formed using a 5 pm HDPE-L-LDPE' IR synthetic resin obliquely uniaxially oriented film.

Then, the thickness was 10 μm so that the molecular orientation axis was 90 degrees.
The extrusion LDPE adhesive layer 4 was laminated using an Idemitsu Petrochemical type L-LDPE resin (Idemitsu polyethylene L1034D) copolymerized with ethylene and butene-1.

In addition, the thickness of the aluminum vacuum-deposited layer is 4A is 100
200 people in 4B, 400 people in 4C and 60 people in 4D.
There are 0 people.

Product 5 of the present invention corresponds to the embodiment shown in FIG. Packaging material of invention product 2 Extrusion L- using L-LDPE resin (Idemitsu polyethylene L1034D) made by Idemitsu Petrochemicals
This is a LDPE resin adhesive layer laminated with spunbond nonwoven fabric (trade name: Syntex) made by Sanso Resin and having a basis weight of I5 g/m2.

Conventional product 1 corresponds to the embodiment shown in FIG. Density 0.96 containing 4.5% by weight of oil furnace carbon black
The uniaxially stretched thermoplastic film layer 17 was formed of a 35 μm thick HDPE diagonally uniaxially oriented film made of HDPE resin (HiZEX) manufactured by Mikata Petrochemical Co., Ltd. and having a g/ci ratio. It is a cross-laminated film with a thickness of 80 μm laminated with an extrusion LDPE resin adhesive layer 4 with a thickness of 10 μm.

Conventional product 2 has a uniaxially stretched thermoplastic film layer 17 of the same resin composition as conventional product 1, which corresponds to the embodiment shown in FIG.
Resin extrusion laminate with adhesive layer 4 and thickness 7
This is a cross-laminated film laminated on both sides of μm aluminum foil JW16.

Conventional product 3 corresponds to the embodiment shown in FIG. A 7 μm thick aluminum foil layer 1 is applied to a 70 μm thick LDPE light-shielding film layer 15 containing 3% by weight of carbon black via a 15 μm thick LDPE extrusion adhesive layer 4.
This is a packaging material in which a flexible sheet layer 6 made of bleached kraft paper with a basis weight of 35 g/m'' is further laminated via an LDPE extrusion adhesive layer 4 with a thickness of 15 μm.

Comparative Example 1 is two light-shielding IDPE-L- with the same resin composition and the same thickness as the invention product 4 corresponding to the example shown in FIG.
A film layer of diagonally uniaxially oriented molecularly oriented LDPE mixed resin was used. Then, the thickness is 10μ so that the molecular orientation axis is 90 degrees.
This is a cross-laminated film laminated with an extrusion adhesive layer 4 using an L-LDPE resin (Idemitsu polyethylene L1034D) copolymerized with ethylene and butene-1.

Comparative product 2 is the same packaging material as inventive product 4, which corresponds to the embodiment shown in FIG. 1, except that the thickness of the aluminum vacuum-deposited layer was changed to 50.

The experimental results are shown in Tables 1 and 2.

The evaluation in Table 2 is as follows.

Excellent Excellent, Good Excellent, Acceptable Within practical limits, needs improvement Problems, Not Practicable The test method is density according to the following: JIS K6760 (=ASTMD-1505)
).

Melt index (Ml)...JIS K6760
(=to ST?I 1238).

Thickness: According to JIS-8118.

Tear strength, according to JIS-8116.

Impact drilling strength, according to JIS-P8134.

Light-shielding property: ASAloo photographic film is placed in a bag made of each packaging material, completely sealed, and exposed to 80,000 lux light for 1 hour, and the light-shielding property is detected and evaluated by the degree of capri of the photographic film.

Ladleability: Hot peeling distance when the open ends of two packaging materials (width 15fl) are pulled at a peeling angle of 22.5 degrees with a load of 45g on each side (hot sealability) immediately after heat sealing at 160°C (cm).

Electrical resistance value: A value measured using a Q-Meg insulation resistance meter (manufactured by Kyoritsu Electric Meter KK) for the film to be tested.

Peeling voltage: Make an endless belt with a width of 35 m and a length of 1350 m using the film to be tested, and connect this belt to a SUS roller (stainless steel) with a load of 500 g and an SO5
Value measured by peeling voltage using a voltmeter (manufactured by Shinan Kagaku KK) when feeding between rollers at a speed of 12 m/min.

Heat-sealing strength over time: Two samples with a film width of 151 m were stacked and heat-sealed at the desired sealing temperature with a sealing pressure of 1 kg/ci and a sealing time of 1 second, and after being left in nature for 3 months (room temperature 20°C, Humidity: 65% RH) Calculate the load required to peel off the seal surface at a 180 degree angle.

Bag making properties: LDPEN with a thickness of 15 μm as a heat-sealing layer on 73 g/m” Kurpankushi 7 as shown in Figure 12.
An outer paper 10 laminated with the inner paper 1 of the packaging material of the present invention
Judgment is made based on the difficulty in generating pinholes, suitability for heat sealing, curling, etc. when the photosensitive material 9 is packaged in a double bag as shown in FIG. 10.11.

〔Effect of the invention〕

The packaging material of the present invention has tear strength even when made into a thin film.
Good impact hole strength, tensile strength, light shielding properties, moisture proofing properties, slipperiness, heat sealability, etc.

As long as the same physical strength is guaranteed, the wall thickness can be significantly reduced compared to conventional products, and as a result, costs can be reduced.

[Brief explanation of drawings]

1 to 9 are partial cross-sectional views of examples of packaging materials for photographic materials according to the present invention. 10 and 11 are views showing a packaging bag using the packaging material for photographic light-sensitive materials according to the present invention, and FIG. 12 is a partial sectional view of the same packaging bag. FIGS. 13 to 17 are partial cross-sectional views of conventional packaging materials for photographic materials. 1...uniaxial molecular orientation thermoplastic resin film layer, 2...
- Aluminum vacuum-deposited layer, 3... Aluminum vacuum-deposited thermoplastic resin film layer, 4... Adhesive layer, 5...
・Light-shielding polyolefin resin-based uniaxially oriented film layer, 6...Flexible sheet layer, 7...Heat-sealing layer Note a and b indicate co-extruded film layers containing a light-shielding substance Patent applicant Fuji Photo Film Co., Ltd. Company agent Patent attorney 1) Masahiro Naka 1 person Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9

Claims (6)

[Claims] (1) A uniaxial molecularly oriented thermoplastic resin film layer formed on the uniaxially molecularly oriented thermoplastic resin film layer and having a thickness of 55 to 50 mm.
Light-shielding property comprising an aluminum vacuum-deposited thermoplastic resin film layer with a thickness of 7 to 70 μm consisting of an aluminum vacuum-deposited layer of 1200 Å, 5% by weight or more of ethylene copolymer resin, and 0.1-20% by weight of a light-shielding substance. and a polyolefin resin-based uniaxially molecularly oriented film layer, the light-shielding polyolefin resin-based uniaxially molecularly oriented film layer is adhered to the aluminum vacuum-deposited layer side of the aluminum vacuum-deposited thermoplastic resin film layer so that the molecular orientation axes thereof intersect. Packaging material for photographic materials characterized by being laminated with layers (2) The packaging material for photographic light-sensitive materials according to claim 1, wherein the uniaxial molecularly oriented thermoplastic resin layer contains carbon black, a conductive substance, or an antistatic agent. (3) Uniaxial molecular orientation thermoplastic resin layer has a density of 0.940g
Packaging material for photographic materials according to claim 1 or 2, which contains 50% by weight or more of polyethylene resin with a polyethylene resin of /cm^3 or more. (4) The photographic material according to claim 1, 2 or 3, wherein the uniaxially oriented thermoplastic resin layer and the polyolefin resin axially oriented film layer have substantially the same composition and thickness. packaging material (5) The light-shielding polyolefin resin uniaxially oriented film layer contains a light-shielding substance, a conductive substance, an antistatic agent, or a lubricant. Packaging materials for photographic materials as described (6) Claims 1 and 2, in which the adhesive contains carbon black, an antistatic agent, or a conductive substance;
Packaging material for photographic materials as described in paragraph 3, paragraph 4 or paragraph 5