JPS6326697B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to improvements in packaging bags for photosensitive materials. In recent years, various packaging materials have been devised, and in particular, so-called composite materials that combine materials such as plastic, paper, and aluminum have been rapidly developed. These materials are mainly used in food products and greatly contribute to the distribution of fresh foods, processed foods, and the like. On the other hand, many photosensitive materials that are more sensitive to environmental influences than foods are usually distributed in a form protected by packaging materials using composite materials such as those described above. However, since the combination of the photosensitive material and the mounting material is not desirable, the following problems exist. In other words, we are conscious of the fact that it is photosensitive and are careful about light shielding properties, but it is easy to generate static electricity, and moisture resistance is insufficient. Because it was difficult to do so, many were left defenseless. The present inventors have discovered that electrification of photosensitive materials occurs particularly when a packaging bag is opened, and has thus come up with the present invention. An object of the present invention is to provide a packaging bag for photosensitive materials that hardly generates static electricity in the photosensitive materials, has sufficient moisture-proofing and light-shielding properties, and does not have any adverse effects on the photosensitive materials. The object of the present invention is to consist essentially of (a) a polyester layer, (b) an aluminum layer, and (c) a polyolefin resin layer containing a light-shielding material and a nonionic antistatic agent, in order from the outside; , (b) and (c) are achieved by a packaging bag for a photosensitive material having a combined optical density of 7.5 or more. In the packaging bag of the present invention, the outermost polyester layer is substantially made of a resin synthesized from dimethyl terephthalate and ethylene glycol, dimethyl terephthalate and 1,4-cyclohexanedimethanol, dimethyl terephthalate, dimethyl isophthalate, etc. This layer may contain an anti-aging agent such as a phosphoric acid type, an anti-blocking agent such as a calcium salt, a dye such as a phthalocyanine type, etc. In the packaging bag of the present invention, the aluminum layer is
For the purpose of moisture proofing, photosensitive materials generally contain many reactive compounds in addition to photosensitive substances.
Since it is easily deteriorated by moisture, a thickness of 200 Å or more is essential, and a thickness of 500 Å or more is more preferable. The purity of aluminum is preferably 97% or higher, 99.3%
The above is particularly preferable. The aluminum layer may be either deposited on a plastic film or aluminum foil. In the packaging bag of the present invention, the innermost layer is a layer made of a polyolefin resin containing a light shielding material and a nonionic antistatic agent. The light shielding material is preferably carbon black, but metal powder, sintered metal powder, organic,
Inorganic pigments may also be used. The nonionic antistatic agent used in the packaging bag of the present invention is specifically glycerin fatty acid (C ₈ - C ₂₂ )
Esters, sorbitan fatty acid ( _C8 - _C22 ) ester, propylene glycol fatty acid (C8- _{C22) ester, sucrose fatty acid (C8-C22 ) ester ,} citric acid monostearyl ester, citric acid distearyl ester, citric acid Acid tristearyl ester, pentaerythritol fatty acid ( _C8 - _C18 ) ester, trimethylolpropane fatty acid (C8- _C18 )
_C18 ) ester, polyglycerol fatty acid (C8 _~
C22 ) ester, polyoxyethylene (20 mol)
Glycerin fatty acid ( _C12 - _C18 ) ester, polyoxyethylene (20 mol) Sorbitan fatty acid ( _C12)
~ _C18 ) ester, polyethylene glycol fatty acid ( _C8 ~ _C22 ) ester, polypropylene glycol fatty acid ( _C8 ~ _C18 ) ester, polyoxyethylene fatty alcohol ( _C12 ~ _C20 ) ether, polyoxyethylene (4~ 50 mol) alkyl ( _C4
above) phenyl ether, N,N-bis(2-hydroxyethyl) fatty ( _C8 - _C18 ) amine, etc., and it is preferable to add 0.05% to 5% by weight, more preferably from 0.05% by weight to the polyolefin resin. is from 0.1% to 2% by weight. In the packaging bag of the present invention, the light shielding material and the nonionic antistatic agent may be in the same polyolefin resin layer, or may be in different polyolefin resin layers adjacent to each other. When they are in the same layer, the antistatic effect is strong with the same amount of charging agent, and when they are in different layers, the rigidity is strong, so the layer structure can be determined depending on the characteristics required of the packaging bag. The polyolefin resin used in the present invention is
These include polyethylene, polyethylene derivatives (for example, ionomers), ethylene copolymers (for example, ethylene and vinyl acetate copolymers), polypropylene, polybutylene, and the like. In the packaging bag of the present invention, between the polyester layer, aluminum layer, and polyolefin resin layer,
In addition to lamination using commonly known lamination methods (wet lamination, dry lamination, hot melt lamination, extrusion lamination, etc.), titanium-based, Applying adhesives such as urethane, corona discharge treatment, printing with printing ink, imprinting with embossing rolls,
The surface can be processed to have a mirror finish, matte finish, satin finish, etc. Further, various coatings such as polyethylene coating, hot melt coating, etc. can be applied to the outer surface. The optical density of the packaging bag prepared in this way is
Must be 7.5 or higher. This is the optical density required to block even highly concentrated photosensitive materials from the effects of light in a normal room. When the aluminum layer is aluminum foil, less light-shielding material is needed for the polyolefin resin layer, but when it is an aluminum vapor-deposited layer and the layer thickness is around 500 Å, the optical density of the polyolefin resin layer is usually
Around 5.0 is appropriate. The photosensitive material to which the packaging bag according to the present invention can be applied is as follows:
Silver halide photographic materials (e.g., X-ray film, printing film, color film, color paper, printing master paper, DTR sensitive material, etc.), diazo photographic materials (4-morpholinobenzenediazonium chloride/zinc chloride) Photosensitive materials containing double salts (e.g., microfilms, adhesion films, printing plates, etc.), azide- and diazide-based photographic materials (photosensitive materials containing para-azidobenzoade, 4,4'-diazidostilbene, etc.), (e.g., copying films, printing plates, etc.), quinonediazide photographic materials (orthoquinonediazide, orthonaphthoquinonediazide compounds, such as benzoquinone (1,2)-diazide-(2)-4-sulfonic acid phenyl ether) (e.g., printing plate materials, copying films, adhesion films, etc.), photopolymers (photosensitive materials containing vinyl monomers, printing plates, adhesion films, etc.),
These include polyvinyl cinnamic acid esters (for example, printing films, IC resists, etc.). Next, the effects of the present invention will be listed. (1) When the packaging bag is opened and the photosensitive material is taken out, static electricity marks are not generated on the photosensitive material. Further, the photosensitive materials are not adhered to each other or the photosensitive materials and the packaging bag due to static electricity, and handling is easy. (2) The physical properties of the packaging bag, such as rigidity, chargeability, and moisture permeability, are as follows:
Since it can be changed depending on the layer thickness of each constituent layer and the amount of additives, it has a wide range of applications. (3) In addition to the moisture resistance of the aluminum layer, heat sealing with the polyolefin resin layer on the inner surface provides complete moisture resistance. (4) Manufacturing costs are low. (5) The packaging bag has high mechanical strength, making it suitable for high-speed, automated packaging processes. (6) Since the outer surface is resistant to friction, there is no need to further protect it by placing it in an outer box. (7) Since no chemical reaction occurs between the photosensitive material and the inner surface, the photosensitive material can withstand long-term storage. EXAMPLES Below, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereby. Example 1 A packaging bag having the structure shown in Table 1 was prepared, and 100 sheets (8 inches x 10 inches) of the high-sensitivity silver halide photographic material Sakurapan SS were packaged. The air conditioning conditions during packaging were 25°C, relative humidity 55%, and a completely dark room.

[Table] After wrapping in film and sealing with impulse heat sealer, it was left standing in an air bath at 60°C and 80% relative humidity for 2 days (during this period in a bright room). After slow cooling, the packaging bag was opened using scissors in a dark room at 25°C and 25% relative humidity, and the contents were gently pulled out. The adhesion between the film and the static mark that occurred upon opening was evaluated. The results are shown in Table 2.

【table】

[Table] As shown in Table 2, the packaging bag according to the present invention is completely antistatic and moisture proof. In addition,
The packaging bags a to d according to the present invention were not adversely affected in terms of photographic properties. On the other hand, in Comparative 2, fogging was observed on the entire surface and in dots through the pinholes of the aluminum foil. Example 2 A packaging bag having the configuration shown in Table 3 was produced.

[Table] 25 sheets of X-ray photosensitive material Sakura X-ray type A were directly sealed and placed in an air bath at 55℃.
It was left undisturbed for a day. After opening, the film was developed with Sakura X Rayfilm developer Conidor X at 20° C. with continuous stirring for 4 minutes and 30 seconds, and fog was measured. e to h according to the present invention
is 0.04, which is the same level as that without heat treatment,
Comparison packaging bag 3 had a value of 0.08, 4 had a value of 0.12, and Comparative packaging bag 5 had a value of 0.05. It can be seen from this that the packaging bag according to the present invention has excellent photographic properties. Example 3 Packaging bags having the configurations shown in Table 4 were produced, and one Sakura PS plate (negative type) SWN was tightly packaged in each bag.

[Table] Note that Comparison 6 allows light to pass through, so even more
It was packaged in 100μ black polyethylene. after that,
After all samples were allowed to stand for two weeks in a bath at 60°C and relative humidity of 90%, the change in sensitivity compared to samples without heat treatment was determined. i decreased by 2%, j decreased by 1%, and 6 decreased by 45%, indicating that the packaging bag according to the present invention is highly effective in improving the storage stability of non-silver salt photographic materials.

Claims (1)

[Claims] 1 Consisting, in order from the outside, of (a) a polyester layer, (b) an aluminum layer, and (c) a polyolefin resin layer containing a light shielding material and a nonionic antistatic agent, and the above (a), (b), and The combined optical density of (c) is
A packaging bag for photosensitive materials characterized by a rating of 7.5 or higher.