JPS6218546A - Material for packaging photosensitive material - Google Patents

Abstract

PURPOSE:To enhance product insertion easiness, slittability, physical strength, heat sealability, etc., by using a packaging film composed of linear low-density polyethylene L-LDPE, high-density polyethylene HDPE, carbon black, and a lubricant. CONSTITUTION:The packaging film is composed of, preferably, 60-93wt% L-LDPE, preferably, 5-40wt% HDPE, preferably, 3-7wt% carbon black, and 0.01-1.0wt% lubricant. The most desirable typical trade mark is 'Ultzex'(R) and 'Dowlex'(R). As the carbon black, oil furnace carbon having a pH of 6-8 and an average particle diameter of 15-30mum is especially preferable.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to packaging materials for photographic materials.

[Prior Art] Various types of packaging materials for photographic materials have been widely put into practical 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 quality 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, gourd, test strength, abrasion strength, etc.), and heat sealing. Suitability (heat sealing strength, cut sealing properties, hot tack properties, contaminant sealing properties, etc.), antistatic properties, flatness, smoothness, etc. are listed. It is considered difficult to have all of these properties in a single film material, and conventionally, high-pressure branched low-density polyethylene (hereinafter referred to as a single-layer film of LDPK and display resin) mixed with carbon black, pigments, etc. has been used. L.D.
Composite laminate films of PE film and flexible sheet layers such as paper, aluminum foil, and cellophane have been used.

Examples of composite laminate films are shown in FIGS. 8 and 9. In the example shown in FIG. 8, a metal foil layer 3 is laminated on an LDPE resin light-shielding film layer 6a via an adhesive layer 2.
The flexible sheet layer 4 is laminated with the flexible sheet layer 4 interposed therebetween. 9 is an example in which an LDPE resin light-shielding film layer 6a is further laminated on the flexible sheet layer 4 of the composite laminate film as shown in FIG. 8 with an adhesive layer 2 interposed therebetween. It has been used for packaging, etc.

The present inventor conducted extensive research to improve packaging materials for photosensitive materials, and discovered a material with improved physical strength by combining two layers of uniaxially stretched films (Japanese Patent Application Laid-Open No. 57-67
No. 54) has already been disclosed.

In addition, packaging materials using linear low-density polyethylene (hereinafter referred to as L-LDPE) resin are also polyethylene-based. rimer and a light-shielding substance of 1 ffift% or more, and the amount of 5 op s or more of the total ethylene polymer is r
=-t, a light-shielding film made of DpE resin has already been disclosed (Japanese Unexamined Patent Publication No. 58-132).
555 Publication).

[Problem that the invention seeks to solve]

Conventional composite laminate films are constructed to improve the physical properties mentioned above, but the physical properties are still not sufficient, resulting in tear holes and peeling of heat-sealed parts during packaging. There were drawbacks such as.

Furthermore, if a large amount of light-blocking substances such as cargo/black are added, the physical strength will deteriorate significantly, so the amount added should be around 3%, and the thickness of the film laminated with other flexible sheet layers should be 70μ or more. was there. For this reason, packaging is difficult because the rigidity of the umbrella laminate film is high, which deteriorates the packaging workability and makes the packaging expensive.

For example, in the laminated film shown in FIG. 8, the aluminum foil 3 is used to provide gas barrier properties, moisture resistance, antistatic properties, etc., and as a result, tear strength, impact puncture strength, Darbo test strength, etc. On the contrary, the problem has worsened to a large extent, resulting in the problem of breakage, especially when packaging heavy items. Therefore, the thickness of the cargo/black LDPE resin light-shielding film layer has been increased to 70 μm or more, but it still does not have sufficient physical strength. Although the physical strength such as tear strength is improved to some extent, the tear strength decreases as the adhesive layer becomes thicker and the adhesive strength increases. Poor sealing properties sometimes caused problems during processing and packaging. In addition, when using a cross-laminated film in which the axially stretched film layers are directly laminated crosswise without using aluminum foil, when the product is packaged in a gusset bag, pinholes occur in the gusset part of the gusset bag, making it difficult to package photographic materials. As a material, it could not be put into practical use due to its poor light-shielding, moisture-proofing, and gas barrier properties.

By using L-LDPE resin as a packaging material, physical strength such as tear strength and Darbo test strength can be increased, and the amount of crosstalk of the light-shielding substance can be increased, and the above-mentioned problems can be improved. However, if the thickness of the film is reduced, wrinkles and film folding occur, resulting in insufficient tensile strength, lubricity, rigidity, moisture resistance, gas IJ resistance, manufacturing suitability, etc.If the film thickness is increased, slit suitability, cut sealing, etc. are insufficient. Sexuality, etc. worsens. Therefore, it has been desired to develop a packaging material that is inexpensive and has excellent film formability, processing machine suitability, and film physical properties.

In particular, packaging materials for dental X-ray films, packaging materials for radiographic films (batch films) for detecting the radiation exposure of radiation handlers, and X-ray films such as those described in Japanese Patent Publication No. 55-24089 are vacuum-treated It has been desired to develop an inexpensive packaging material that can satisfy all the characteristics required as a packaging material for photographic materials even with a single thermoplastic resin film layer.

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 improved product insertability, slit suitability, physical strength, heat seal suitability, etc.

[Means for solving problems]

The present invention includes at least L-LDPE resin, high-density polyethylene (hereinafter referred to as [)PE) resin, and cartilage. The inventors have discovered that the above objects can be achieved by using a light-shielding film containing four types of black and lubricant.

That is, the present invention combines 50 to 95% by weight of L-LDPE resin, 5 to 49.5% by weight of HDPE resin, and 0% by weight of carden bra.
．． The present invention relates to a packaging material for photographic materials comprising a film containing at least four components: 1 to 10% by weight and 0.01 to 1.0% by weight of a lubricant.

L-L, which is the first component essential to the film of the present invention.
DPK resin is an ethylene-α-olefin copolymer resin obtained by copolymerizing ethylene with α-olefin having 3 to 13 carbon atoms, preferably 4 to 10 carbon atoms, by a low-pressure method, and has an ethylene content of 85 to 10 carbon atoms. 99.5 molti, α-olefin content is 0.5 to 15 molti, and has a structure with short branches in a straight chain.

Generally, this material is L-LDPE resin (L1n@ar
It is called Lowdan・n5ltyヱsly tyL@+a・that is, the abbreviation for the head of linear low-density 4-lyethylene.

The most common polymerization processes are gas phase and liquid phase methods that use medium/low pressure equipment, but in recent years French □CDF
developed an ionic polymerization method using high-pressure equipment. In particular, low-pressure L-LDPE resin is preferred because of its low cost.

If you give a specific example by product name, Yu = 73? -L (UCC)
, Dowlex (Dow Chemical), Sflair (DuPont Canada), Marlex (Philips), Neoze, Kusu and Urtoze, Kusu (Mitsui Petrochemical), Ikkoku Sunilex (Japan Petrochemical), Stamilex (DSM)
), NUC Polyethylene-LL and TUFLIN (Nippon Unicar).

α-olefins include butene-1, octene-1, hexene-1,4-methylpentene-1, heptene-1,
etc., in an amount of 0.5 to 15 mol of the polymer. Among these α-olefins, 4-methylpentene-1, hexene-1 and octene-1 are preferred. The density is generally considered to be that of low-medium density polyethylene resin, but commercially available products have a density of 0.87 to 0.9597 cm.
Many are within the range of 3.

Among these L-LDPE resins, those with an ethylene content of 90 to 99.5 molt and an α-olefin content of 0.5 are particularly preferable from the viewpoint of physical strength and heat seal strength.
~10 molti, melt index (hereinafter referred to as MI)
is 0.8 to 30 t7.10 min (ASTMD-1238
). The density is 0.870 to 0.940 f/an” (A
STMD-1505), α-olefin has 6 or more carbon atoms
These are L-LDPK resins produced by eight low-pressure liquid phase processes and vapor phase processes. The most preferred representative product name is L-LDPE in which 4-methylpentene-1 having 6 carbon atoms is used as an α-olefin side chain in ethylene.
Examples of resins include Urtose and Kusu manufactured by Mitsui Petrochemical Co., Ltd., which contain 8-carbon octene as the α-olefin side chain.
Examples of L-LDPE resins using No. 1 include Stamilex manufactured by DSM and Dowlex manufactured by Dow Chemical Company. (The above three companies' products are low pressure, L by the "liquid phase process"
-LDPE resin. ) As a low-pressure gas phase process product, there is TUFLIN manufactured by Nippon Unicar Co., Ltd., which uses xene-1 as the α-olefin side chain.

The content of L-LDPE resin in the film of the present invention is about 50 to 95% by weight, preferably about 60 to 93% by weight.

The HDPE resin, which is the second component essential to the film of the present invention, has a density of
(ASTM D1505-67 test method) 0.940-0
．． It is 97013.

The manufacturing method is medium pressure method (1) Phillips method, (
2) There is a standard method, and a low pressure method is a method in which ethylene is polymerized at low pressure using a Ziegler catalyst. Preferably, the film of the present invention has a linear structure with few branches obtained by a low-pressure method, has high crystallinity, and has a density of 0.9.
45~0.970f, M3, and M I (ASTM
D 1238-65T test method) is 0.3 to 1.5 t
/10 minutes. The content of HDPK resin in the film of the present invention is 5 to 49.
It is about 5% by weight, preferably 5 to 40% by weight.

Carbon black, which is the third component essential to the film of the present invention, can be classified into raw materials: gas plastic, lily, oil furnace black, channel black, anthracene black, acetylene black, oil smoke, pine smoke, animal black, vegetable plastic, There are many other things. Among these, 7 Arnes car black is preferable in terms of light-shielding properties, cost, and improved physical properties, while acetylene car is more expensive but has an antistatic effect. Chenkagen black, which is a modified by-product carbon black, is preferred. If necessary, the former and the latter can be mixed according to the required characteristics. On the other hand, among these carbon blacks, pH is 5 to 9, average particle size is 10 to 120 mμ,
Particularly preferred is oil furnace carbon black with a diameter of 6 to 8 and an average particle diameter of 15 to 30 mμ. By using such a carbon black with a particle size of 15 to 30 mμ, it is possible to improve the photosensitivity of the photographic material with less fogging. It has a high light-shielding ability, does not have a negative effect on photographic materials, and does not easily cause pinholes such as glue lumps and fish eyes even when added to thermoplastic resin films. A packaging material having a number of advantages can be obtained.

Forms for blending carbon black into a blend resin of L-LDPE resin and HDPE resin (hereinafter referred to as L-LDPE-HDPE resin) include powder addition method, paste addition method, moisturizing addition method, compound method, and master patch. There are laws etc. Among these, the MASTER PA, CH method is preferable in terms of cost, prevention of workplace contamination, and the like.

Japanese Patent Publication No. 40-26196, which is a publicly known document, describes a method of making a master patch for polymer strength by dispersing carbon black in a solution of a polymer dissolved in an organic solvent. The publication describes a method for making a master patch by dispersing carbon black in polyethylene.

In the case of the masterbatch method, a masterpatch is first prepared by mixing carbon black with a high concentration of 2% by weight or more, generally 10% by weight or more, into an LDPE resin. This master patch is weighed and mixed with L-LDPE-)IDPE-based resin so that the amount of carbon black in the final product becomes a predetermined value.

Two advantages can be recognized in this method.

First, unlike directly mixing carbon black with L-LDPE-HDPE resin, this method is easier to mix and disperse, reduces costs, and improves fish eyes.

Secondly, compared to L-LDPE-HDPE resin, a mixed system of LDPE resin and L-LDPK-)IDPE resin has better processability when manufacturing a film. L-LDPE resin may be used as the master patch resin to reduce the cost of carbon black mixing. L-LDPE-HDPE is used as a pace resin for master patch.
It is possible to use any thermoplastic resin that can be mixed with the thermoplastic resin, but polyolefin resins are preferred. In particular, the MI of the master patch resin is L/-LDPE-HD.
Thermoplastic resins having higher thermoplastic properties than PE-based resins are desirable.

Note that the same applies to cases where other light-shielding substances are used.

The present inventors have discovered that conventional LDPE single resin and HDPE single resin substitutes have had problems when used as packaging films.
- The influence of carbon black formulation was tested using a mixed resin of LDPE resin and HDPE resin. As a result, L-
An unexpected result was found in that when carbon black was blended into the LDPE-HDPE resin, the physical strength significantly increased, contrary to the case of the MPG resin alone or the LDPE resin alone.

That is, I (DPI-based resin films and LDPE-based resin films have originally lower strength than L-LDPE-HDPE-based resin films, but the strength decreases particularly when Cargen Black is added. On the other hand,
The strength of the L-LDPE-HDPE resin film is improved by adding carden black.

The same thing can be said about L-LDPE-based resin films, but L-LDPE-based resin films have low tensile strength and rigidity, have poor sliding properties without the addition of a lubricant, and have poor processing suitability. Not only was it inferior in properties, but it also had problems such as poor slitting suitability due to its large elongation, making it difficult to put it to practical use as a packaging material for photographic materials using a single film alone. The effect of adding carbon black to L-LDPE-HDPE resin is 0.1% by weight.
It appears clearly in the IM amount, 3% by weight.
It becomes noticeable when the amount is exceeded, but if the amount added is further increased, the occurrence of bumps will increase and the cost will increase.

If the amount exceeds 20% by weight, problems arise particularly in terms of spots often occurring due to poor dispersion of carton black and poor light-shielding properties due to pinholes. Moreover, the cost is also relatively high.

Therefore, the blending amount of car plastic and resin should be determined based on economic efficiency, generation of lumps,
It is preferably about 0.1 to 10% by weight in terms of tear strength etc.
It can be said that about 3 to 7 weights is particularly preferable.

In order to add the same amount and make the light shielding property as good as possible,
It is best to add cargan black 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).

The lubricant, which is the fourth essential component of the film of the present invention, not only improves suitability for processing machines and makes it easier to insert the product, but also prevents the generation of static electricity during film molding and packaging of photographic materials. . Furthermore, it prevents film formation and kinging and improves film formability by T-die method, inflator method, etc.

If the amount of lubricant added is large, the above characteristics can be greatly improved, but the heat-sealing properties may be adversely affected, the photographic material may be adversely affected (inhibition of development), stickiness may occur, etc. This causes problems such as dirt becoming more likely to stick to the surface. Therefore, add a lubricant of 0.01 to 1. It is preferable to add about i% by weight of O. In order to improve the above-mentioned various properties without adversely affecting the photographic light-sensitive materials, and to improve the lubricating properties with the photographic light-sensitive materials, trimethylpolysiloxane and fatty acid amide-based lubricants (oleic acid amide, erucic acid amide) are used. , stearamide, ethyl amide, etc.) and fatty acid-based lubricants are particularly preferred.

Representative examples of commercially available lubricants preferred for the present invention are described below, but the present invention is not limited thereto.

Silicone lubricant: Various dimethylpolysiloxanes (Shin-Etsu Silicone, Toshi Silicone) Oleic acid amide lubricant: Armosli 7°CP (Lion Akzo), Neutron (Nippon Fine Chemical), Nytron E18 (Nippon Fine Chemical), Amide 0 (Nitto Chemical), Alflow E10 (NOF), Diamond 0-200 (Nichibei Kasei), Diamond G
Erucic acid amide lubricant such as -200 (Nippon Kasei): Stearic acid amide lubricant such as Alflo P-10 (NOF); Alflo 5-10 (Nippon Oil), 2, -Tron 2
(Nippon Fine Chemical), Diamit 200 (Nippon Kasei) etc. Bis fatty acid amide lubricant: Bisamide (Nippon Kasei),
Diamond (ZOK Nippon Kasei) 'Armorwax - EBS (Although it does not fall into the above classification, which includes Lion and Acrylic, it is also preferable to use Kao Soap's ``Electrostrits Ya-'', which has strong anti-static properties and a large antistatic effect.

Other resins that can be blended with L-LDPE-HDPE resins other than HDPE resin include LDP.
E resin is preferably used, but other polyolefin resins, such as medium density polyethylene (hereinafter MD
PE) resin, various polypropylene resins, ethylene-vinyl acetate copolymer (hereinafter referred to as EVA) resin, and ethylene-ethyl acrylate copolymer □
Combined (hereinafter referred to as EEA) resin, ethylene-methacrylate copolymer (hereinafter referred to as EMA) resin, I-lysobutylene resin, ethylene-acrylic acid copolymer (hereinafter referred to as F:A)
A) It is also possible to blend resins, etc., as long as the basic properties are not changed.

Various additives other than those mentioned above can be added in required amounts to each layer of the present invention, if necessary.

Representative examples of additives are described below, but the present invention is not limited thereto, and any additive can be selected from among all known additives.

(Additive types) (Typical 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, Organotin-based etc. (3) Antistatic agent; cationic activator, anionic activator,
Nonionic activators, bifacial activators, etc. (4) Flame retardants; phosphoric esters, halogenated phosphoric esters, halogenides, inorganic substances, phosphorus-containing lyols, 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, carbon fibers, etc. (7) Coloring agents; inorganic pigments (AL-Fs 205, T
102- ZnO, CdS, etc.), organic pigments, dyes, etc. (8) Blowing agents; inorganic blowing agents (carbonic acid, ammonia, soda bicarbonate), organic blowing agents (thoron type, azo type), etc. (9) Vulcanizing agents; vulcanization Accelerators, accelerators, etc. α-deterioration inhibitors; ultraviolet absorbers, antioxidants, metal deactivators, peroxide decomposers, etc. α9 coupling agents; silane-based, titanate-based, chromium-based, aluminum-based, etc. (6) As explained above, the packaging material for photographic materials of the present invention, such as various thermoportable resins and rubbers, may be a single layer of L-LDPE-HDPE resin light-shielding film, or may be a combination of other flexible sheet layers. It may be laminated.

When used as a single layer of L-LDPE-HDPE resin light-shielding film, it has light-shielding properties, gas barrier properties, moisture proofing properties, rigidity, physical strength (tensile strength, tear strength, impact puncture strength, Rude test strength), heat seal strength, cut sealability,
A thickness of 50 μm or more is required to ensure flatness, sliding properties, and prevention of pinholes in the heat seal part.
In particular, in the case of heavy products, highly photosensitive products, and products that are easily affected by humidity, oxygen gas, sulfur gas, etc.,
Preferably, a film thickness of 100 μm or more is required. On the other hand, the film thickness is preferably 250 μm or less, preferably 10% or more thinner than conventional LDPE films, from the viewpoints of low temperature heat sealability, film slitting suitability, bag making suitability, cut sealability, cost, etc.

Practical film thickness when used as a single layer of L-LDPE-HDPE resin light-shielding film is 50-250
μm1 is preferably 70 to 180 μm1, and more preferably 100 to 160 μm.

When laminating with other flexible sheet layers, L-L
DP HDPE resin light shielding film layer is i, -t, op
Rigidity, moisture resistance, and barrier properties are better than when using E resin or L-LDPE-LDPE resin film layer, so it can be made thinner by 10 inches or more. Practically speaking, L-
The thickness of the LDPE-HDPE resin light shielding film layer is 30
~200 μm, preferably 40 to 150 μm, more preferably 50 to 100 μm.

Flexible sheet layers that can be laminated on the L-LDPE-HDPE resin light-shielding film layer include thermoplastic resin films (including unstretched, uniaxial molecular orientation, and biaxial molecular orientation);
For example, various polyethylene resins, ethylene copolymer resins,
Polypropylene resin, vinyl chloride resin, polyvinylidene chloride resin, polyamide resin, polycargonate resin, fluororesin, ? There are known films such as polyester resins and films of modified resins thereof. In addition, metal thin film processed films (typically aluminum vacuum-deposited film), metal thin film processed paper, cellulose acetate film, cellophane, polyvinyl alcohol film, various papers, various metal foils (typical example aluminum foil), nonwoven fabrics. There are known flexible sheet layers such as , warp, perforated film, and foamed sheets of polyethylene, polystyrene, I-urethane, and the like. If necessary, the L-t and Dpt-IDPE resin light-shielding film layers of the present invention may be used as two layers.

The above-mentioned flexible sheet layers can be used alone or in combination of two or more depending on the required characteristics.

Even when laminated with other flexible sheet layers to form a composite film, the L-LDPE-)IDPE resin light-shielding film layer must be placed on the surface in contact with the photographic material.

The L-LDPE-IDPE resin light-shielding film layer is 2
It may also be part of a film in which more than one layer is coextruded.

Among the flexible sheet layers, a metal thin film processed flexible sheet layer which is particularly suitable for packaging photosensitive materials will be described in detail.

Metal thin film processed flexible sheet layer Particularly desirable flexible sheet layers include biaxially oriented nylon film, biaxially oriented polypropylene film, biaxially oriented polyester film, cellophane, unstretched polypropylene film, reinforced high-density polyethylene film, and biaxially oriented polypropylene film. There is an axially oriented high density polyethylene film.

If necessary, a uniaxial molecularly oriented thermoplastic resin film (H
DPE resin, polypropylene resin, L-LDPE-H
DPE resin, I-lyamide resin, polyester resin, L
- A film made of LDPE resin or the like with uniaxial molecular orientation in any one of vertical, horizontal, and diagonal directions may be used as a metal thin film processed flexible sheet layer.

Metal thin film processing flexible sheet layer The thickness of the flexible sheet layer is 8 to 50 μm from the viewpoint of metal thin film processing cost.
is preferred, particularly 10 to 30 μm.

The metal thin film processing method (also referred to as the total refraction thin film forming method) is a method for forming a flexible sheet on both sides or one side (for example, light-shielding It can be provided on one side of the layer side.

The metal thin film contains At, Sn + Zn tco, Ni,
All metals such as Fe#Cu, alloys, and other metals capable of forming a thin film can be used, but aluminum (HT) is the most suitable in terms of cost and ease of processing.

The metal thin film has a rating of 55 to 12 in terms of physical strength as a laminate, light-shielding property, Vi-electric protection, moisture-proofing, cost, and quality.
A thickness of 00X is preferred. That is, if the thickness is less than 55X, the metal thin film processing flexible sheet layer alone cannot reduce the charge generated on the layers on both sides of the metal thin film, and the thickness of the flexible sheet layer and light shielding layer on both sides of the metal thin film increases. Otherwise, it will not be possible to ensure the moisture-proofing and light-shielding properties necessary for packaging materials for photosensitive materials.

If the thickness exceeds 12,001 mm, antistatic, moisture-proof, and light-shielding properties can be ensured, but problems arise in terms of cost and vacuum deposition methods such as deterioration of the flexible sheet layer due to heating and reduction in physical strength of the finished laminated film. Therefore, it is difficult to put it into practical use. In the case of an aluminum vapor deposited film, the thickness is preferably 70X or more, 80 to soo 1 for normal use, and more preferably 100 to 600X.

If necessary, the surface of the flexible sheet layer forming the metal thin film may be subjected to known activation treatment or anchor treatment, or a protective layer may be provided on the metal thin film.

L-LDPE-IDPE resin light shielding film layer and other 7
A conventional method may be used to laminate the lexical sheet layers. For example, methods that do not use an adhesive include a hot plate sealing method, an internal school method, an ultrasonic welding method, a vibration friction welding method, a rotational friction welding method, a hot air welding method, and the like. On the other hand, lamination methods using adhesives include wet lamination method, dry lamination method, hot melt lamination method, extrusion lamination method (including coextrusion lamination method), coextrusion T-die or blown film molding method, etc. is used. The thickness of the adhesive layer obtained by the extrusion lamination method using thermoplastic resin, which is the most effective lamination method for these, is usually 7 μm to 100 μm, preferably 13 μm to 50 μm, but this thickness depends on cost, coating speed, and the laminate. This value is not particularly limited because it is determined based on the total thickness, etc.

Since the packaging material of the present invention is used for photographic materials, it is necessary to have light-shielding properties. Therefore, it is necessary that at least one of the layers constituting the laminate has light-shielding properties. That is, it is essential to ensure the light-shielding property of the L-LDPE-HDPE resin light-shielding film layer alone, but in order to further cover the light-shielding property, a flexible sheet layer,
A light-shielding substance may be contained in one or more of the adhesive layer or any other layer, and the light-shielding layer may be made of colored paper, aluminum foil, galvanized thin-layer steel plate, etc. with a thickness of 5 μm or more and 50 μm.
The following metal foils or other layers with light-shielding properties such as paper with a metal vapor-deposited layer of 55 to 12001 (e.g. aluminum vapor-deposited paper) or metal vapor-deposited film (e.g. aluminum vapor-deposited film) are laminated or printed. The light-shielding property can be covered using a method such as adding .

Hereinafter, typical embodiments of the present invention will be described with reference to cross-sectional views, but the present invention is not limited thereto.

1 to 6 are cross-sectional views of the product of the present invention.

Figure 1 shows L-L, which is the most basic packaging material of the present invention.
This is a single layer 1a of a DPK-HDPE resin moisture-proof light-shielding film.

FIG. 2 shows a light-shielding flexible sheet layer 4a or an L-LDPE-I (DPE-based resin moisture-proof light-shielding film layer 1a) laminated on the L-LDPE-HDPE resin moisture-proof light-shielding film layer 1a shown in FIG. 1 via an adhesive layer 2. It is a laminated film with a three-layer structure.

In Figure 3, a metal foil layer 3 is laminated on an L-LDPE-HDPE resin moisture-proof light-shielding film layer 1a via an adhesive layer 2, and a flexible sheet layer 4 or L-L layer is further laminated via an adhesive layer 2.
DPK-HDPE resin moisture-proof film layer 1 laminated 5
It is a laminated film with a layered structure.

FIG. 4 shows a laminated metal thin film processed light-shielding film layer 5& in which a metal thin film layer 5 is formed on a flexible sheet layer 4 or an L-LDPE-HDPE resin moisture-proof film layer 1 in place of the metal foil 3 in FIG. It is a 6-layer laminated film.

FIG. 5 shows a three-layer structure in which a flexible sheet layer 4 or an L-LDPE-HDPE resin moisture-proof film 1 is laminated on an L-LDPE-HDPE resin moisture-proof light-shielding film I1.41a via an adhesive layer 2. It is a layered film.

Figure 6 shows the L-LDPE-HDPE resin moisture-proof light-shielding film JU1a and the light-shielding flexible sheet layer 4a or 1jL.
-LDPE-HDPE resin moisture-proof light-shielding film layer 1a is coextruded to form a two-layered film.

Figure 7 shows LDPE, the most basic of conventional packaging materials.
The resin light-shielding film layer 6a is a single layer.

FIG. 8 shows a structure in which a metal foil layer 3 is laminated via an adhesive layer 2 on an LDPE resin light-shielding film layer 6a, which has been conventionally used in products that particularly require moisture resistance, and a flexible sheet layer 4 is further laminated via an adhesive layer 2. It is a laminated film with a five-layer structure.

FIG. 9 is an example of a packaging material that is conventionally used for color photographic paper and the like and requires physical strength. An LDPE resin light-shielding film layer 6a is further laminated on the laminated film of FIG. 8 via an adhesive layer 2. It is a 7-layer laminated film.

The packaging material for photographic light-sensitive materials of the present invention is also suitable for packaging light-sensitive materials. Photographic light-sensitive materials include ), silver oxide photographic materials, diazo photographic materials, photosensitive resins, self-developing photographic materials, diffusion transfer photographic materials, and the like.

The packaging materials for photographic materials of the present invention include single-layer flat bags, double-layer flat bags, square bottom bags, self-standing bags, single-layer gusseted bags, double-layered gusseted bags,
All known forms such as a film sheet, the inside of a moisture-proof box, and a leader paper are possible.

The bag manufacturing method is based on conventionally known plastic film sealing methods such as heat sealing, impulse sealing, ultrasonic sealing, and high frequency sealing, depending on the properties of the laminated film used. In addition, it is also possible to make bags using an appropriate adhesive, pressure-sensitive adhesive, or the like.

[Effect]

The packaging material for photographic light-sensitive materials of the present invention is a film having an L-LDPE-HDPE resin light-shielding film layer on the photographic light-sensitive material side, which is a mixture of lubricant, carmen black, L-LDPE resin, and HDPE resin in a specific ratio. It is.

The lubricity, tear strength, and impact puncture strength required for packaging materials for photographic materials that cannot be achieved with a single resin film layer using HDPR resin, LDPE resin, or L-LDPE resin.
rru? Test strength, film cutting property, hot tack property, low temperature heat sealing property, heat sealing strength, drop strength,
Light blocking ability, contaminant sealability, cut sealability, hermetic sealability (vacuum packaging suitability), processing machine suitability, bag making suitability, rigidity,
Many properties such as antistatic properties have been improved.

〔Example〕

Preferred embodiments of the present invention and their effects will be described below.

Products 1 to 4 of the present invention correspond to the embodiment shown in FIG.

The composition is as shown in Table 1, and Mitsui Petrochemical's L-LDPK resin (Urtze, Kusu 2
021L) or α-olefin with 8 carbon atoms (
L- manufactured by DSM in the Netherlands using octene-1 of C8)
LDPE resin (Stamilex 1026) and density 0
．． 9697cm') [DPE resin (HiZEX')
This is a single film layer of an L-LDPE-HDPE resin light-shielding film layer 1a, which is a blend of 3300F) and further contains 3% by weight of oil furnace carden bra, and 0.05% by weight of oleic acid amide as a lubricant.

Products 5 and 6 of the present invention correspond to the embodiment shown in FIG.

L-LDPE-HDPE with the composition shown in Table 1 and a thickness of 50 μm
An aluminum foil 3 with a thickness of 7 μm is laminated on the light-shielding resin film layer 1a via an LDPE adhesive layer 2 with a thickness of 13 μm, and a flexible sheet layer 4 with a basis weight of 35 is further laminated via an LDPE adhesive layer 2 with a thickness of 13 μm. This is a 5-layer laminated film made by laminating 11m thick Nishikrait paper of t/-.

Comparative product 1 corresponds to the embodiment shown in FIG. The product of the present invention is a single layer L-LDPE resin light-shielding film (L-LDPK) that has the same composition and the same thickness except that it does not contain only HDPE resin.
The resin is Mitsui Petrochemical's Tsuruto Zex 2021L.
).

Comparative product 2 corresponds to the embodiment shown in FIG. 3% by weight of cargan black in HDPE resin and DSM LDPE resin (Stamilex+1026) that does not contain lubricant.
It is a single layer of added L-LDPE resin light shielding film.

Conventional product 1 corresponds to the embodiment shown in FIG. car? Thickness 205 containing 3% by weight of plastic and 0.05% by weight of lubricant.
It is a single layer of μm LDPI resin light-shielding film.

Conventional product 2 corresponds to the embodiment shown in FIG. 8, and has a thickness of 70 mm and contains 3% by weight of Karn black and 0.05% by weight of lubricant.
LDPE resin light-shielding film layer 6a with a thickness of 15 μm
An aluminum foil 3 with a thickness of 7 μm is laminated via an LDPE resin extrusion adhesive layer 2, and a further layer with a thickness of 15 μm is layered.
This is a packaging material in which bleached kraft paper with a weight of 3,597 m2 is laminated with an LDPI resin extrusion adhesive layer 2 of 3,597 m2.

Conventional product 3 corresponds to the embodiment shown in FIG. Conventional product 2 L
The thickness of the DPE resin light-shielding film layer 6a is changed from 70 μm to 5 μm.
A LDPE resin light-shielding film layer 6a with a thickness of 50 μm is further applied to the bleached kraft paper of the laminated film with a thickness of 0 μm via a LDPI resin extrusion layer 2 with a thickness of 15 μm.
It is a packaging material with a seven-layer structure.

Although the above examples are representative examples of preferred embodiments of the packaging material for photographic light-sensitive materials of the present invention, the present invention is not limited thereto, and other known materials and flexible sheet layers may be used. A combination is possible.

Table 1 shows the layer structure, materials used, thickness of each layer, etc. of the invention products 1 to 6, comparative products 1 to 2, and conventional products 1 to 3, and Table 2 shows the results of comparing the characteristics. .

As the LDPE extrusion adhesive layer 2 in the examples, Mirason 14 (MIs, 1
t/10 min, density 0. 91997 cm"), car gun blacks include Mitsubishi Kasei Oil Furnace Pla, Ri 44B (average particle size 21 mμ, pH 7.7), L
The DPK film layer is DFD-01 manufactured by Nippon Unicar.
11 (MI 2.4 P710 min, density 0.92397
cm”), and the HDPK resin is Mitsui Petrochemical No. 1 Izex 3300F (MI 0.90 f7
10 minutes, density 0.95497 cm") were used, respectively.

The evaluation in Table 1 is as follows.

Fair; Very good; Good; Excellent; Fair; Within practical limits, needs improvement: Problematic; Not practical. The test method is as follows.

Density: According to ASTM D-1505.

Melt Index (MI): ASTM 1238
In accordance with

*1 Destruction strength: The number of times the packaging material is bent using a device based on the U.S. military standard MIL-8131 until pinholes occur in the packaging material and light-shielding properties cannot be ensured. The higher the number, the more difficult it is to evaluate the strength; pinholes occur after 2 or fewer attempts.

Needs improvement: 3-7 times I: 27-50 times, Good: 51-100 times, Excellent: 101 times or more , 1 for 80,000 lux of light
Detects the degree of fog on photographic film by time exposure and light shielding properties.

evaluate.

Judgment is based on the hot peel distance (α) when pulled at a peel angle of 22.5 degrees with a load of 45 f on one side.

*44 The photosensitive material 11 is made of an outer paper 13 made by laminating a 15 μm thick LDPE layer as a heat-sealing layer on Krutsukutsuk paper with a near 3 f/m2 suitability and an inner paper 14 of the packaging material of the present invention as shown in Fig. 10. Judging from the difficulty of pinhole formation when double-bagged, suitability for heat sealing, curling, etc.

*5 Sliding angle: Cut out a part of the 7-t to be tested,
This is pasted on the bottom of a block with a load of 2002 measuring 75 meters long and 35 meters wide.

On the other hand, a part of the sheet to be tested is similarly cut out and pasted on an inclined surface, the sheet surface of the block is placed on the inclined surface, and the oblique angle of this inclined surface is changed, so that the block slides. Read the starting angle.

*6 Heat sealing strength: Layer two samples with a film width of 15 m and heat seal at the desired sealing temperature with a sealing pressure of 1ψ♂ and a sealing time of 1 second. After cooling completely, peel off the sealed surface at a 180 degree angle. Find the load required for Unit 1 A specific representative example in which the packaging material of the present invention is applied to a double gusset bag for color photographic paper will be described with reference to FIGS. 10 and 11.

FIG. 10 is a sectional view of the packaging bag 12 that houses the photographic material 11. This packaging bag 12 is composed of an outer paper 13 and an inner paper 14, and the outer paper 13 is composed of a laminated flexible sheet layer 4 or 1 and a heat seal layer 6 or 1, as shown in the partial cross-sectional view of FIG. It is formed by The inner paper 14 is made of the packaging material of the present invention, for example the packaging material shown in FIG. 1 or FIG. 6 may be used. These outer paper 13 and inner paper 14 are folded together at the ends by a center seal part and a heat seal part 15 at the end, are heat-sealed and adhered with an adhesive 18, and are further bonded with tape 1.
6 is pasted and sealed.

〔Effect of the invention〕

The packaging material of the present invention, whether it is a single layer film or a laminated film, has good tear strength, impact hole scratching strength, Ruge test strength, tensile strength, light shielding property, moisture proofing property, 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 the drawing]

1 to 6 are partial sectional views of packaging materials according to embodiments of the present invention, and FIGS. 7 to 9 are partial sectional views of conventional packaging materials. FIG. 10 is a partial sectional view of one embodiment of a packaging bag using the packaging material of the present invention.
Figure 1 is a partial cross-sectional view of the same outer paper. 1...L-LDPE resin moisture-proof film layer, 1&...
L-LDPE resin moisture-proof light-shielding film layer, 2... PP resin layer or M-HDPE resin layer, 2 a-PP resin light-shielding layer or M-HDPE resin light-shielding layer, 3... adhesive layer, 4
...Flexible sheet layer, 41L...Light-shielding flexible sheet layer, 5...Metal thin film layer, 5a...Metal thin film processing flexible sheet layer (=metal thin film forming flexible sheet layer), 6...LDPE Resin film layer, 6a... LDPE resin light-shielding film layer, 7... Metal foil layer, 11... Photographic material, 12... Packaging bag,
13...Outer paper, 14...Inner paper, 16...Tape,
17... Heat seal part, 18... Adhesive. Patent applicant Fuji Photo Film Co., Ltd. Agent Patent attorney 1) Hiroshi Nakamasa 1st! ” 2nd
rM m3 Figure 4 Figure 5 Figure 6 (!! Figure 7 Figure 8 Figure 911!I 10T!!! Figure 11 Figure 12 Procedural amendment (voluntary) November 14, 1985

Claims (5)

[Claims] (1) Linear low density polyethylene resin 50-95% by weight
and high-density polyethylene resin 5-49.5% by weight, carbon black 0.1-10% by weight, and lubricant 0.01-1.0
Packaging material for photographic materials consisting of a film containing at least four components in weight percent (2) The packaging material according to claim 1, in which one or more flexible sheet layers are laminated on the outside of the film. (3) α-olefin of linear low density polyethylene resin is 4-methylpentene-1, hexene-1, octene-1
1. The packaging material according to claim 1 or 2, which is any one of 1. (4) Density of high-density polyethylene resin (ASTMD15
05-67 test method) is 0.945 to 0.97 g/cc, and the melt index (ASTMD1238-6
5T test method) is 0.3 to 1.5 g/10 minutes, the packaging material according to claim 1, 2 or 3. (5) 50% by weight or more of carbon black has a pH of 5 to 9
, the packaging material according to claim 1, 2, 3, or 4, which is oil furnace carbon black with an average particle diameter of 10 to 120 mμ.