JPH0118408B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a silver halide photographic material containing in its constituent layers an oil-in-water polymeric dispersion (latex) formed by polymerizing monomers. In general, silver halide emulsion films used for producing photographic light-sensitive materials are required to have specified strengths not only in terms of photographic sensitivity characteristics but also in terms of film physical properties. For this reason, conventionally, by incorporating a latex made by polymerizing various monomers into a silver halide emulsion layer or other constituent layers, the physical properties of the film formed after being coated on a support and dried are improved. Various attempts have been made to improve, for example, scratch strength, dimensional stability, flexibility, pressure resistance and drying properties. For example, latex such as vinyl acetate of U.S. Patent No. 2,376,005, latex of alkyl acrylate of U.S. Pat. No. 3,325,286,
Latex of n-butyl acrylate, methyl acrylate, styrene, butadiene, vinyl acetate, acrylonitrile, etc. of No. 45-5331,
Latexes such as alkyl acrylates, acrylic acid, and sulfoalkyl acrylates of No. 46-22506 are used for the above purpose. However, when these latexes are mixed with a gelatin solution or in the presence of salts, the particle size of the latex particles becomes non-uniform, causing them to aggregate or settle, and some latexes tend to be heavy. Since the polymer that makes up the coalescence itself is ionic, it has drawbacks such as having an adverse effect on the photographic properties of silver halide. In addition, surfactants are sometimes added to polymerized latexes for the purpose of stabilizing polymer particles, but it is not uncommon for surfactants to adversely affect photographic performance. Therefore, an object of the present invention is to provide a latex that is sufficiently stable when incorporated into the constituent layers of a silver halide photographic light-sensitive material, and furthermore, to provide a latex with sufficient scratch strength and dimensional stability without affecting photographic performance. The object of the present invention is to provide a latex that can improve film properties such as thermal stability, flexibility, pressure resistance, and drying properties. A second object of the present invention is to provide a method for using latex with a high antistatic effect, and a third object of the present invention is to provide a method for using latex that has a large antistatic effect. The present invention provides a latex that maintains sufficient stability when mixed with gelatin even when polymerized without the use of gelatin. The object of the present invention is to provide a silver halide photographic material characterized in that at least one of its constituent layers contains an oil-in-water polymerization dispersion containing a repeating unit represented by the following general formula. [General formula] (In the formula, A is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or

[Formula], R and R′ each represent a hydrogen atom or a methyl group, R″ represents a hydrogen atom, an alkyl group, or an aryl group, n,
Each m represents a positive integer of 1 to 50. However, the oil-in-water dispersion does not substantially contain a hydrophobic substance, or if it does, it contains an antistatic agent). Next, examples of compounds represented by the general formula [] are shown below, but of course the compounds are not limited to these. Compound example Methods for synthesizing these monomeric compounds are described, for example, in JP-A-48-786. A latex using the monomer represented by the above general formula [] can be obtained using a commonly used emulsion polymerization method. For example, a polymerization initiator and, if necessary, a polymerization initiation accelerator and an emulsifier are added to degassed distilled water, and to this are added the monomer of the general formula [] and 2 to 3 monomers copolymerizable with it. 50% by weight
Add a molecular weight regulator if necessary,
It can be synthesized by heating to 30° to 90°C and stirring for several hours or by standing still. As the polymerization initiator, water-soluble inorganic peroxides such as potassium persulfate and ammonium persulfate, or water-soluble organic azo compounds such as α,α'-azobiscyanoisobarexic acid sodium salt are used. Moreover, when using an inorganic peroxide as a polymerization initiation promoter, acidic sodium sulfite may be used. The following compounds are known as examples of copolymerizable monomers. (1) (meth)acrylic acid esters (for example,
butyl acrylate, methyl methacrylate) (2) Vinyl esters (e.g. vinyl acetate,
(vinyl propionate) (3) (meth)acrylamides (e.g. acrylamide, N,N-dimethylacrylamide, diacetone acrylamide) (4) Styrenes (e.g. styrene, methylstyrene) (5) Halogenated olefins (e.g. , vinyl chloride) (6) Acrylonitrile, etc. The present invention is not limited to these monomers, and a latex with a monomer that can be copolymerized with the monomer of the present invention can also exhibit sufficient effects. If necessary, two or more of these monomers may be used in combination. Generally, the copolymerization ratio is set so that the latex is stable in water.
Naturally, the stability varies depending on the combination, and the copolymerization ratio cannot be specified individually. Emulsifiers that can be used include anionic surfactants such as sodium alkylsulfonates and alkylbenzenesulfonic acids, nonionic surfactants such as polyoxyalkylene derivatives, amphoteric surfactants such as sulfobetaine type, and cationic surfactants such as quaternary ammonium salts. Surfactants can be mentioned, but in the latex used in the present invention, the amount of emulsifier can be reduced from the usual amount by appropriately combining the monomer of the general formula [] and a monomer that can be copolymerized with it. It has been found that it is possible to obtain a latex which is not only sufficiently stable in water without using an emulsifier, but also sufficiently stable without causing any agglomeration even when added to a silver halide photographic light-sensitive material.
This is considered to be one of the great advantages of the present invention, considering that emulsifiers used in the production of latex have adversely affected not only photographic performance but also antistatic performance. In addition to this, it has been found that the antistatic performance is improved by using the monomer of the general formula []. Specifically, the effects described above are probably due to the stabilizing effect of the latex by the ethylene oxide group or the propylene oxide group, which will be described in the following examples. Although the polymer composition of the latex is specifically shown below, it is of course not limited to this. Polymer example Examples of synthesis of latex according to the present invention are shown below. Synthesis Example 1 (Latex with the composition of Polymer Example (1)) A thermometer and a dropping funnel stirring rod were attached to a 500 ml four-headed colben, and 320 ml of water was added to dissolve 0.8 g of sodium dodecylbenzenesulfonate. The system is raised to 80°C and placed in a nitrogen atmosphere. After quickly adding 0.4 g of ammonium persulfate and 0.4 g of sodium bisulfite dissolved separately to this, a mixture of 64 g of ethyl acrylate and 16 g of the monomer of compound example (1) was added dropwise from the dropping funnel over about 1 hour. do. After the dropwise addition was completed, stirring was continued for 4 hours at 80°C, and then the mixture was cooled to room temperature to complete the polymerization. Solids concentration 19.5%, transmittance 75% (transmittance at 670nm at solids concentration 0.5wt%), molecular weight
150000 (measured by osmotic pressure method). Synthesis Example 2 (Latex containing the composition of Polymer Example (2)) A stirrer, thermometer, and dropping funnel were set in a 500 ml four-headed flask, 320 ml of water was added, and the system was made into a nitrogen atmosphere. To this, the system was raised to 80°C without adding any emulsifier, 0.4 g of ammonium persulfate was added, and ethyl acrylate was immediately added.
A mixture of 56 g and 24 g of the monomer of Compound Example (2) was added dropwise over about 2 hours. After the dropwise addition was completed, the mixture was further stirred at 80°C, and then cooled to room temperature to complete the reaction. The obtained latex was stable, with a solid content concentration of 20.1wt% and a transmittance of 80% (solid content
It exhibited a transmittance at 570 nm at 0.5% by weight) and a molecular weight of 40,000 (measured by osmotic pressure). Synthesis Example 3 (Latex containing the composition of Polymer Example (8)) In the same manner as Synthesis Example 2, styrene 72 and Compound Example (6) were added.
A latex was synthesized from 8 g of the monomer. In particular, no emulsifier was used. The obtained latex had a solid content of 18.5% by weight, a transmittance of 50% (measured by the same method as in Synthesis Example 2), and a molecular weight of 100,000 (by osmotic pressure method). The latex according to the present invention is an excellent latex that overcomes the drawbacks of latexes conventionally used in the industry. That is, even when mixed with hydrophilic colloids such as gelatin or in the presence of various salts, latex particles do not aggregate, are extremely stable, and do not cause color staining due to interaction with color developing agents. Furthermore, the dye produced by the reaction between the coupler and the color developing agent does not change color. Furthermore, it has been found that since the polymer constituting the latex of the present invention is nonionic, it not only does not impair the sensitivity of photosensitive silver halide, but also does not cause fogging. Furthermore, when synthesizing the latex according to the present invention, it is not only possible to reduce the amount of emulsifier that is normally used, but also it is possible to synthesize the latex without using an emulsifier. It has been found that, for example, deterioration of antistatic performance and deterioration of coating properties can be significantly improved. As mentioned above, the latex of the present invention has an excellent antistatic effect, but in order to make this antistatic effect even more effective, it is necessary to use a latex obtained from the monomer of the present invention. It is preferable to use an antistatic agent in combination by a method such as impregnation. The antistatic agents used in combination in the present invention include all known antistatic agents for photography, such as anionic antistatic agents, cationic antistatic agents, amphoteric antistatic agents, and nonionic antistatic agents. Next, the method of impregnating the latex obtained from the monomer of the present invention with the above-mentioned antistatic agent can be roughly divided into the following five methods. 1. Mix a solution of an antistatic agent dissolved in a water-soluble organic solvent and a polymer latex. Thereafter, the organic solvent is removed if necessary. 2. A solution of an antistatic agent dissolved in a substantially water-insoluble organic solvent is mixed with the polymer latex, and stirred vigorously if necessary. Thereafter, the organic solvent is removed if necessary. 3 Add the antistatic agent directly to the polymer latex and mix, stirring vigorously if necessary. 4. Mix a solution obtained by dissolving a polymer obtained by a normal polymerization method in an appropriate organic solvent with a solution in which an antistatic agent is added to an appropriate aqueous solvent such as water, and a surfactant is added if necessary. The polymer is emulsified and dispersed by stirring vigorously. after that,
Remove organic solvent if necessary. 5. During latex production, an antistatic agent is present and polymerized. By using the above-mentioned impregnation method, the polymer in the polymer latex can be impregnated with one or more antistatic agents, and the polymer latex composition used in the present invention can be obtained. The antistatic agent mixed in the polymer latex of the present invention does not need to be impregnated in its entirety into the polymer particles, but it may be partially impregnated and the remainder present in the dispersion medium of the polymer latex. Anything is fine. Preferably, the impregnation rate of antistatic agent (weight of antistatic agent impregnated into polymer particles in polymer latex/weight of antistatic agent added to polymer latex) is at least about 10%, and preferably from 20% to 20%. 90% is more preferred. In the above-mentioned impregnation method, examples of the organic solvent used to dissolve the antistatic agent and the polymer include those described in US Pat. No. 2,801,171 and the like. To give specific examples, examples of water-soluble organic solvents include acetone, methanol, ethanol, acetonitrile, dioxane,
Dimethylformamide, etc., and substantially water-insoluble organic solvents include ethyl acetate, butanol, chloroform, carbon tetrachloride, benzene,
Examples include hexane and ethyl ether. Each of these solvents can be used alone or in combination of two or more. Further, it is desirable that the concentration of the polymer latex used in the above method etc. is 5 to 30% by weight. Further, the concentration of the antistatic agent in the organic solvent solution is arbitrary, but is usually 1% or more, preferably 10% or more. Furthermore, the concentration of the organic solvent solution of the polymer used in the fourth impregnation method is arbitrary, but it is preferably 10% or more. In the polymer latex composition used in the present invention, the concentration of the antistatic agent to the polymer latex is 10 to 200% by weight, preferably 20 to 100% by weight.
The above object of the present invention can be achieved by including the compound in the outermost layer of the photosensitive material within this range. When the latex of the present invention having such good properties is added to a photographic element and coated on a support, it exhibits good dimensional stability and rolling properties, as well as scratch strength, flexibility, pressure resistance, and drying properties. etc. will also be greatly improved. The term "photographic element" as used herein refers to a non-light-sensitive layer and a light-sensitive emulsion layer provided on a support. Examples of the non-photosensitive layer include an intermediate layer, an antihalation layer, a filter layer, and a protective layer. Further, the aqueous dispersion of the present invention can be advantageously used alone or in combination with a hydrophilic colloid such as gelatin in each of the above layers. For example, when using the latex of the present invention as an intermediate layer, the polymer particle concentration is 5 to 60% by weight, preferably 10 to 50% by weight, and the latex is coated on a photosensitive silver halide emulsion layer by a conventional method. good. Alternatively, it can be mixed with a hydrophilic colloid such as gelatin in any proportion and applied. Preferably, the amount of polymer particles in the latex of the invention is from 5 to 100 parts by weight per 100 parts by weight of hydrophilic colloid. Furthermore, the latex of the present invention can also be applied to photosensitive layers as described above. In the embodiment of application to the photosensitive layer, silver halide is prepared in the latex of the present invention (polymer particle concentration 5 to 50% by weight), and silver halide is prepared in a mixed solution of the latex of the present invention and a hydrophilic colloid such as gelatin. It is possible to prepare silver halide, or to prepare silver halide in a hydrophilic colloid such as gelatin, and then add the latex of the present invention. As the silver halide, any silver halide such as silver chloride, silver bromide, silver iodide, silver chlorobromide, silver chloroiodide, silver iodobromide, silver chloroiodobromide, etc. can be used. The method for preparing silver halide is single
Various known preparation methods such as the jet method, double jet method, or direct mixing method can be arbitrarily selected. Also, silver halides prepared by various different methods may be mixed. Further, the silver halide emulsion according to the present invention may be sensitized with a known chemical sensitizer or stabilized with a stabilizer. Hydrophilic colloids include gelatin, agar, albumin, hydrolyzed cellulose derivatives, synthetic binders such as polyvinyl alcohol, water-soluble polymers, gelatin derivatives, and monomers with polymerizable ethylene groups. Examples include those obtained by graft copolymerization. Example 1 Control Sample 1 A silver iodobromide gelatin emulsion containing 3 mol% of silver iodide was chemically sensitized using a gold sensitizer and a sulfur sensitizer, and 4
-Hydroxy-6-methyl-1,3,3a,7-
After adding tetrazaindene and mucochloric acid, it was coated onto a polyethylene terephthalate support at a silver content of 50 mg/dm ² . Comparative Sample [A] A comparative sample [A] was prepared in exactly the same manner as the control sample, except that 5% by weight of a latex consisting only of ethyl acrylate was added to the gelatin in the emulsion immediately before coating. Comparative sample [B] Completely the same as comparative sample [A] except that the composition of the latex to be added was a copolymer of 90% by weight of n-butyl acrylate and 10% by weight of sodium 2-acrylamide-2-methylpropanesulfonate. A comparative sample [B] was prepared. Sample No. 1 of the Invention This sample was prepared in exactly the same manner as Comparative Sample [A] except that the latex of Synthesis Example 1 was used as the latex added. Sample No. 2 of the present invention was prepared in exactly the same manner as Sample No. 1 of the present invention except that the latex of Synthesis Example 2 was added. Sample No. 3 of the present invention This sample is exactly the same as Sample No. 1 of the present invention except that the latex of Synthesis Example 3 is added. Sample No. 6 of the present invention Exactly the same as sample No. 1 of the present invention except that latex of polymer example (9) was added. Invention Sample No. 7 Exactly the same as Invention Sample 1 except that the latex of Polymer Example 13 was added. When a part of the coating liquid of each sample was observed under bright light, it was found that comparative sample [A]
Only aggregates were observed. Further coating and observation revealed that coating unevenness was observed in comparative samples [A] and [B], but in sample No. 1 of the present invention,
No. 2 and No. 3 were not recognized. Further, each sample was exposed to wedge light and subjected to the development treatment shown below, and then the effects on dimensional stability and photographic performance were examined, and the results shown in Table 1 were obtained. Processing process Development: 30°C for 45 seconds Fixing: 25°C for 35 seconds Washing: 15°C: 35 seconds Drying: 45°C: 20 seconds The composition of the developer is as follows. Phenidone 0.4g Metol 5g Hydroquinone 1g Anhydrous sodium sulfite 60g Sodium carbonate monohydrate 54g 5-Nitroimidazole 100mg Potassium bromide 2.5g Add water to 1 and adjust the pH to 10.20. In addition, for dimensional stability, the radius of curvature of the sample is 20
After being left in an atmosphere of 20% relative humidity and 30°C for 3 days, it was measured and evaluated.

[Table] As is clear from Table 1, the latex according to the present invention has improved dimensional stability without any adverse effect on photographic performance. Example 2 Gelatin was coated as a protective layer on control sample 1 in Example 1 so that the dry film thickness was 1μ, but samples were prepared in which 10% by weight of the gelatin was added with latex having the following composition. did. Control sample 2 Comparative sample without latex addition [C] Butyl acrylate latex synthesized using 2% by weight of sodium dodecylbenzenesulfonate as an emulsifier. Sample No. 4 of the present invention Latex synthesized in Synthesis Example 1 Sample No. 5 of the present invention Latex synthesized in Synthesis Example 2 Sample No. 8 of the present invention The latex of Polymer Example (9) was used. Sample No. 9 of the Invention The latex of Polymer Example (13) was used. The samples prepared as described above were left in an atmosphere of 25° C. and relative humidity of 50% and 20%, respectively, and then the surface resistance was measured. The results are shown in Table 2.

[Gelatin aqueous solution composition]

Gelatin 20g Water 500ml 20% saponin 1ml 2% mucochloric acid 5ml Adjust the volume to 1 with water. Next, 200ml each was divided into five samples, no antistatic agent was added to the first sample, and 2g of the following antistatic agent was added to the second and third samples.
For the fourth and fifth samples, the antistatic agent was dispersed in latex using the following manufacturing method, and the amount of antistatic agent was 1.
After adding 2g and 3g of each, each of the five compounds was coated as a protective film on the silver iodobromide emulsion layer to a dry film thickness of 1.5μ and dried to prepare a sample. [Antistatic agent] (Production example of polymer latex of the present invention impregnated with the above antistatic agent) 50 ml of polymer latex containing 20% of the above polymer [11] was added to an isopropanol solution containing 25% of the above antistatic agent. Add dropwise to 10 ml and stir for several minutes using a magnetic stirrer. Next, 1.5 g of gelatin is added and dissolved, and then cooled and solidified. This coagulated material was washed with running water for 24 hours,
The desired product is obtained by removing isopropanol. These samples were conditioned at 25℃ and 20% relative humidity for 3 hours, rubbed with rubber in a dark room under the same air-conditioning conditions, and then subjected to normal development processing, and the appearance of static marks was observed. The situation was evaluated in five stages: [no outbreak], [small outbreak], [current outbreak], [large outbreak], and [maximum outbreak]. In addition, with the remainder of the sample, cut into quarters per developer solution for an ordinary automatic processor to check the precipitation in the developer solution.
After processing 10 sheets (processing time 30 seconds, temperature 35℃),
The developer was observed and the degree of precipitation was evaluated in four stages: [no precipitation], [small precipitation], [during precipitation], and [large precipitation]. The results are shown in Table 3. For the automatic processing, a continuous roller conveyance type automatic developing machine was used, which can perform development, fixing, washing, and drying all at once. The composition of the treatment liquid used was as follows. Hydroquinone 10g Anhydrous sodium sulfite 70g Boric anhydride 1g Sodium carbonate (monohydrate) 20g 1-phenyl-1,3-pyrazolidone 0.35g Sodium hydroxide 5g 5-methylbenzotriazole 0.05g Potassium bromide 15g Glutaraldehyde bisulfite 15g Glacial acetic acid 8g Add water to make 1.

[Table] As is clear from Table 3, the samples according to the present invention (No. 4, No. 5) have the disadvantage of precipitation of antistatic agent into the developer when a large amount of antistatic agent is used. I can see that it is improving. Furthermore, it can be seen that the antistatic performance is also extremely good. Embodiments of the invention are described below. 1. A patent claim characterized in that the outermost layer contains a polymer latex polymer composition in which an oil-in-water polymer dispersion obtained by polymerizing monomers represented by the general formula is impregnated with an antistatic agent. A silver halide photographic material as described in the range.

Claims (1)

[Scope of Claims] 1. A silver halide photographic material characterized in that at least one of its constituent layers contains an oil-in-water polymerization dispersion containing a repeating unit represented by the following general formula. [General formula] (In the formula, A is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or [Formula], R and R' are each a hydrogen atom or a methyl group, and R'' is a hydrogen atom, an alkyl group, or an aryl group. The group is n,
Each m represents a positive integer of 1 to 50. However, the oil-in-water dispersion does not substantially contain a hydrophobic substance, or if it does, it contains an antistatic agent).