JPH04264443A - Silver halide photographic sensitive material having antistatic property - Google Patents

Abstract

PURPOSE:To obtain excellent antistatic property without dependance on humidity by incorporating conductive carbon black into an antistatic layer. CONSTITUTION:An antistatic layer containing conductive carbon black is provided. The conductive carbon black is produced, for example, by continuous pyrolysis method, etc., by which acetylene gas is introduced to a reaction furnace preliminarily heated to effect pyrolysis, the furnace temp. rises, and then the decomposition reaction is automatically effected. Namely, the carbon black is soot obtd. by inadequate combustion, and is preferably of <=100mum particle size. This conductive carbon black has black color and has an effect to prevent halation. Thereby, this carbon black can be effectively used when it is incorporated to the halation preventing layer of a photographic sensitive material.

Description

Description: FIELD OF INDUSTRIAL APPLICATION This invention relates to antistatic silver halide photographic materials. [0002] Silver halide photographic materials use films, paper, etc. as supports, but these have low conductivity and have caused various problems. One of these problems is that when coating a film, paper, etc. with a coating solution containing silver halide, the coating is applied at high speed, but during the friction and rubbing by the rollers, the coating becomes electrically charged. This is a problem in that silver halide is fogged when discharged (electrostatic fog). If an antistatic layer is applied before applying a coating solution containing silver halide, electrostatic fogging can be prevented. Second, when a user uses a photosensitive material, the material becomes electrically charged and dirt and dust can adhere to the photosensitive material, forming undesirable images such as pinholes during exposure and photographic processing. Another problem is that the photosensitive materials stick together, making workability difficult. What is important in these problems is that the antistatic properties must be good both before and after the processing of development, fixing, and washing with water. In order to solve these problems, methods have been considered to improve the conductivity of the support and coated surface of photographic light-sensitive materials. , polymers, etc. have been attempted. For example, U.S. Patent Nos. 2,882,157 and 2,972
, No. 535, No. 3,062,785, No. 3,262,
No. 807, No. 3,514,291, No. 3,938,9
Polymers such as those described in U.S. Pat. No. 99, etc., U.S. Pat.
Surfactants such as those described in , No. 552,972 and No. 3,655,387 are known. However, although these are effective for certain film supports and photographic materials, they may have an adverse effect on the photographic properties of other photographic materials, may lose their antistatic effect during photographic processing, or may be used under low humidity conditions. In some cases, there is no antistatic effect at all. [0007] Also, US Pat. No. 3,753,716 and US Pat. No. 4,266,015 describe antistatic effects due to the effect of reducing the friction coefficient of fluorine-containing polymers. In order to prevent static electricity on both the front and back sides of a photosensitive material, this fluorine-containing polymer must be contained in the top layer of both the front and back surfaces, and this fluorine-containing polymer must be contained in the upper layer of the photosensitive layer of the photographic light-sensitive material. become. Most fluorine-containing polymers have a water-repellent effect, and in order to obtain antistatic properties on both the front and back surfaces, the topmost layer containing a fluorine-containing polymer is used to repel water during the development of the photographic material. This may cause development problems due to hydration and adversely affect photographic properties. [0008] Also, as a method for preventing static electricity that is not dependent on humidity, Japanese Patent Application Laid-open Nos. 143431/1982 and 98656/1983 disclose
A method using conductive metal oxides is described in No. These are those in which conductive metal oxide fine particles are used by themselves or coated with fibrous potassium titanate. A common drawback of these products is the possibility of agglomeration of particles during coating during the product manufacturing process, which may stain the coated material. Further, conductive metal oxides are very expensive, leading to a considerable increase in cost. SUMMARY OF THE INVENTION An object of the present invention is to provide a silver halide photographic material having excellent antistatic properties without humidity dependence. [0010] The present invention is achieved by providing at least one antistatic layer containing conductive carbon black. [0011] The conductive carbon black preferably has good dispersibility and low specific gravity. The reason for this is that it is known that conductivity is caused by contact between conductive powders, and that conductivity depends on the volume percent of the conductive powder. This has the advantage that only a small amount of carbon black is required. The conductive carbon black of the present invention is produced by a continuous pyrolysis method, etc., in which acetylene gas is passed into a preheated reaction furnace to cause thermal decomposition, the furnace temperature rises, and the decomposition reaction automatically proceeds thereafter. Conductive carbon black such as acetylene black, lamp black, which is soot that has been incompletely burned with a flame that does not disturb oil, tar, resin, etc., and other high structure furnace blacks.
It is also possible to use one type alone or a combination of two or more types, and the particle size is 10.
The thickness is preferably 0 μm or less, particularly preferably 0.01 to 2 μm. If the particle size is 100 .mu.m or more, the coated material will be stained when the coating solution is applied during the production of photographic light-sensitive materials, and carbon black will not be uniformly contained due to insufficient dispersion, resulting in a loss of commercial value. The conductive carbon black of the present invention is black and has an antihalation effect, and can be used more effectively by incorporating it into an antihalation layer of a photographic light-sensitive material. The antistatic layer may also serve as a backing layer, undercoat layer, antihalation layer, anticurl layer, adhesive layer, etc.
Furthermore, other additives such as various surfactants, hardeners, matting agents, dispersants, adhesives, antifoggants, stabilizers, etc. used in this field can be used as necessary. The conductive carbon black used in the present invention can also be used in combination with other antistatic agents.
Examples include polypyrrole latex described in JP-A-69621, thermosetting conductive polymers described in Japanese Patent Application No. 2-26442, and conductive metal oxides described in JP-A-56-143431 and JP-A-63-98656. . [0016] It is unexpected that by using the conductive carbon black of the present invention, antistatic properties that are independent of humidity can be obtained, and it is possible to produce photographic materials with antistatic properties at low cost. Met. Examples of the support used in the present invention include cellulose nitrate film, cellulose acetate film, cellulose acetate butyrate film, cellulose acetate propionate film, polystyrene film, polyethylene terephthalate film, polycarbonate film, and other laminates thereof. There are things etc. Further examples include paper coated or laminated with baryta or α-olefin polymers, particularly polymers of α-olefins having 2 to 10 carbon atoms, such as polyethylene, polypropylene, and ethylene butene copolymers. In the present invention, another antistatic agent can be used in combination with the protective layer or other layers of the photographic light-sensitive material, thereby making it possible to obtain more preferable antistatic properties. Such antistatic agents include U.S. Pat. No. 2,882;
No. 157, No. 2,972,535, No. 2,982,6
No. 51, No. 3,062,785, No. 3,262,80
No. 7, No. 3,428,456, No. 3,457,076
No. 3,454,625, No. 3,514,291, No. 3,552,972, No. 3,615,531,
No. 3,655,387, No. 3,753,716, No. 3,938,999, No. 4,070,189, No. 4
, No. 266,015, No. 4,891,306, etc. The silver halide photographic material according to the present invention will be explained. Binders for the photographic constituent layers include proteins such as gelatin and casein, cellulose compounds such as carboxymethyl cellulose, hydroxyethyl cellulose, and dextran, agar, sodium alginate, sugar derivatives such as starch derivatives, and synthetic hydrophilic colloids such as polyvinyl alcohol and poly-N- Vinyl pyrrolidone, polyacrylic acid copolymer, polyacrylamide, or derivatives thereof and partial hydrolysis can also be used in combination. The gelatin mentioned here refers to lime-treated gelatin, acid-treated gelatin, enzyme-treated gelatin, and the like. The antistatic layer of the present invention is mainly composed of the above-mentioned binder and conductive carbon black, and the amount of conductive carbon black used is 0.00% per 1 g of binder.
0.01 g to 10 g is preferable, and 0.05 g to 5 g is particularly preferable. If it is less than 0.01g, sufficient conductivity cannot be obtained,
If it exceeds 10 g, it is not preferable because it has an adverse effect on photographic properties. As the light-sensitive silver halide emulsion layer, any one known in the art can be used, but preferably it is an emulsion layer used in high-sensitivity silver halide light-sensitive materials, silver halide light-sensitive materials for high-temperature rapid processing, etc. can be mentioned. The composition of the photographic processing liquid, such as a developer, a development stopper, a fixer, etc. in the photographic light-sensitive material of the present invention, can be determined according to the purpose and the type of photographic material, and those known to those skilled in the art can be used. . [Examples] The present invention will be illustrated below with reference to Examples, but the present invention is not limited thereto. Example 1 The following coating, which also served as a backing layer, was formed on a polyester film support that had been subjected to an aqueous subbing process with a subbing composition containing an epoxy compound disclosed in JP-A No. 60-213942 for the purpose of making it hydrophilic. Apply the antistatic layer as shown below. Method for preparing antistatic coating liquid Gelatin

50g
water

500ml 17% conductive carbon black dispersion SD9553 (Dainippon Ink & Chemicals Co., Ltd.)
Co., Ltd.)
60g
10% SNP-4N (manufactured by Nikko Chemicals)
20ml 2,4-dichloro-6-hydroxy-S-triazine salt (10% aqueous solution)

Add 50ml water
1000ml Conductive carbon powder material used here SD9553
is a 17% dispersion of acetylene black in an aqueous dispersion. Sample 1 was prepared by coating at a moisture content of 50 ml/m2. As a comparative sample, Comparative A was prepared in the same manner except that conductive carbon powder was not added. In addition, Comparative b was prepared in the same manner except that SD-9082 (36% dispersion, manufactured by Dainippon Ink and Chemicals Co., Ltd.), which is an aqueous dispersion of thermal black, was used instead of the conductive carbon SD-9553. . Thereafter, each sample was heated at 40°C for 6 days. After heating, the sample was cut and subjected to photographic development. As a developing solution, AC for Silver Master manufactured by Mitsubishi Paper Mills Co., Ltd., which is a commercially available processing liquid for silver complex diffusion transfer, was used, and as a stabilizer, ST for Silver Master manufactured by Mitsubishi Paper Mills was used. Photographic processing was performed using a P-460R processor manufactured by Mitsubishi Paper Mills. [0029] To determine the antistatic ability, samples before and after treatment were tested at 25°C, 20% RH (relative humidity), and 25°C, 50% RH (relative humidity) for 2 hours to examine humidity dependence.
After leaving it for a while, the surface resistance value was measured using a Hiresta surface resistance meter model HT-210 manufactured by Mitsubishi Yuka Co., Ltd. As for the surface resistance, the lower the resistance value, the better the antistatic property. Furthermore, membrane strength is necessary to obtain commercial value of the sample. If the film strength is weak, the film may peel off during photographic processing or when handled by users, causing it to stick to processor rolls and clog them, or contaminating processing solutions, which is really necessary in terms of commercial value. The evaluation method is to make square scratches at 5 mm intervals on the surface of the sample with a knife, immerse it in the above AC treatment solution for Silver Master at 30°C for 30 seconds, rinse with water for 1 minute, and then rub the surface with a tissue. It was evaluated by Those that did not come off at all were marked as ○, those that peeled off slightly were marked as △, and those that peeled off considerably were marked as ×. These results are shown in Table 1. [Table 1] [0032]
As is clear from Table 1, Sample 1 containing conductive carbon black has good levels of conductivity and film strength, has a much lower surface resistance value than Comparative A, and exhibits humidity dependence in antistatic properties. It can be said that the antistatic property is quite excellent. Therefore, it has been revealed that the embodiments of the present invention provide a silver halide photographic material with excellent antistatic properties and no humidity dependence. Example 2 Sample 2 was prepared in the same manner as in Example 1 except that the amount of conductive carbon black SD9553 added to the coating solution for applying the antistatic layer was 75 g. Furthermore, Sample 3 was prepared in the same manner except that the amount of the powder material added to the coating liquid was 100 g. Hereinafter, the same evaluation as in Example 1 was performed, and the results shown in Table 2 were obtained. [Table 2] [0035] As is clear from the results in Table 2, it is clear that the embodiments of the present invention provide a silver halide photographic material with excellent antistatic properties and no humidity dependence. became. Example 3 JP-A-64-69621 was added to the antistatic coating liquid of Example 1.
Sample 4 was prepared in the same manner except that 50 g of the polypyrrole latex described in the above issue was added. Further, Sample 5 was prepared in the same manner except that 50 g of the thermosetting conductive polymer described in Japanese Patent Application No. 2-26442 was contained instead of polypyrrole latex. Sample 6 was prepared in the same manner except that 50 g of conductive tin oxide crystals described in JP-A-56-143431 were added. Coating liquids containing no conductive carbon black contained in the coating liquids of Samples 4, 5, and 6 were prepared, and then applied and heated in the same manner to obtain Comparative C, Comparison d and comparison e were created. Hereinafter, the same evaluation as in Example 1 was performed, and the results shown in Table 3 were obtained. [Table 3] As is clear from the results in Table 3, Samples 4, 5, and 6 of the present invention have lower surface resistance values than Comparison a to Comparison e, and also have a lower humidity dependence. There is no gender. In other words, it has been revealed that the embodiments of the present invention provide a silver halide photographic material with excellent antistatic properties and no humidity dependence. Effects of the Invention As is clear from the results of the Examples, it has been revealed that the embodiments of the present invention provide a silver halide photographic light-sensitive material that is independent of humidity and has excellent antistatic properties.

Claims (1)

[Claims] 1. A silver halide photographic material having at least one antistatic layer, characterized in that the antistatic layer contains conductive carbon black.