JPS6224779B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a silver halide photographic material,
More specifically, the present invention relates to a method for dispersing photographic additives. Generally, various photographic additives are dispersed in silver halide photographic materials. There are several methods for this dispersion. One method is to dissolve the photographic additive in water or an organic solvent such as a lower alcohol or acetone, and add the solution to the coating solution. If the additive is difficult to dissolve in water or the organic solvent, it is dissolved in an organic solvent that is immiscible with water, and the solution is dispersed in water containing a protective colloid agent in the form of fine droplet-like particles. A so-called oil protect dispersion is known in which the oil is added to the coating solution. Examples of water-immiscible organic solvents used in this dispersion method include methyl, ethyl, benzyl, nonyl and decyl phthalates, benzyl and hexyl benzoates, triphenyl phosphate and tricresyl phosphate. Examples include phosphoric acid esters, as well as diethyl laurylamide, tetrahydrofurfuryl succinate, and the like. However, not all oil-soluble photographic additives necessarily have good solubility in these organic solvents; for example, some couplers and UV absorbers have poor solubility even in these solvents. Therefore, during emulsification and dispersion using a colloid mill or homoblender, during the elapsed time after addition to an emulsion or gelatin solution, or during the coating and drying process, additive crystals may precipitate, or small droplets may aggregate with each other. This may lead to uneven coating and reduced product quality. In addition, in recent years, high-temperature rapid photographic processing has been carried out in color photographic materials, and thinning of the photosensitive layer is required to improve processing characteristics.If conventional oils are used, the oils may deposit on the coating film. There are many problems such as the membrane becoming brittle and unable to withstand treatment. As an improvement over this, an example of using a polymer mainly composed of alkyl acrylate as an oil agent (polymer dispersion) has been published in Japanese Patent Publication No. 30494/1983. Separately, photographic additives are dissolved in a water-miscible organic solvent such as acetone or tetrahydrofuran, mixed with latex, and then the organic solvent is distilled off to form photographic additives into latex particles. A method for obtaining a fine dispersion without applying mechanical shearing force (latex dispersion) is disclosed in JP-A-51-59942 and JP-A-51-59942.
Published in issue 59943. This polymer dispersion and latex dispersion, especially latex dispersion, is an excellent method that, unlike oil protect dispersion, does not cause oil to precipitate on the coating film or cause the film to become brittle. However, when using it for dispersing certain photographic additives, especially couplers, etc., it is necessary to combine a conventionally known hydrophobic vinyl monomer mainly composed of butyl acrylate and a hydrophilic vinyl monomer containing sodium sulfonate. Latexes made of polymers could not provide sufficient photographic performance. In other words, when a coupler is filled in latex and dispersed, the higher the proportion of hydrophobic monomer in the latex, the higher the amount of coupler (the amount of coupler filled per unit weight of latex) increases, which reduces the storage stability of the resulting dye image. is good, but color development is poor when color development is performed, and color development is good when the proportion of hydrophilic monomer is high, but color development is poor when color development is performed, and color development is good when color development is performed, but color development is poor when the proportion of hydrophilic monomer is high, but coupler loading is There are disadvantages such as poor quantity and matte coating surface. This is because the coupler is hydrophobic and the color developer with which it reacts is hydrophilic. Therefore, a latex that is hydrophobic during dispersion and hydrophilic during development is desired. JP-A-51-59942 and JP-A-51-59943 exemplify a monomer containing active methylene (acetoacetoxyethyl methacrylate) as a copolymerization component. However, when this type of active methylene is incorporated into a polymer, it dissociates under strong alkali conditions and is useful for making it hydrophilic (US Pat. No. 4,088,499), but it is not completely dissociated under normal color development conditions of PH10-12. Therefore, although the hydrophobization during dispersion is satisfactory, the hydrophilization during development is insufficient. Research Disclosure (RD) 19146
(1980) described a copolymer latex consisting of a hydrophobic monomer (50-90% by weight), a carboxylic acid-containing monomer (5-45%), and a sulfonic acid-containing monomer (2-5%) as an "alkali-activated latex." Disclosed. This latex is certainly an excellent filling latex that becomes hydrophilic under weak alkaline conditions.
By including sulfonic acid in the latex, the latex becomes stable when loaded with additives.
However, monomers containing sulfonic acid are generally expensive, and it is difficult to stably carry out emulsion polymerization while containing a large amount of electrolyte (sulfonic acid monomer). Therefore, a latex active under alkaline conditions that is inexpensive and can be synthesized stably is desired. The purpose of the present invention is to improve the addition of photographic additives, that is, their dispersion.
The purpose of the present invention is to provide a latex for filling (hydrophobic when used, hydrophilic when developed). As a result of extensive research, the present inventor has found that an aqueous polymer dispersion (latex) having at least one monomer unit represented by the following general formulas (), (), and () as a constituent component is suitable for photographic use. It has been found that the above object can be achieved by containing and dispersing additives. General formula () (-A-) _x x (In the formula, A represents a vinyl monomer containing carboxylic acid, and x is 2 to 30% by weight based on 100% by weight of the polymer.) General formula () (- B-) _y y (In the formula, B represents a vinyl monomer containing an alkali metal salt or an organic salt of a carboxylic acid, and y is 0.5 to 8% by weight based on 100% by weight of the polymer.) General formula () ( -C-) _z z (wherein, C represents a hydrophobic vinyl monomer,
z is 50 to 95% by weight based on 100% by weight of the polymer. ) Furthermore, the present inventors have discovered that the target alkali-activated filling latex contains a carboxylic acid-containing vinyl monomer (30 to 2% by weight) and a hydrophobic vinyl monomer (95 to 2% by weight).
50 wt.
It has been found that it can be very easily synthesized by neutralizing 8% by weight of the carboxylic acid (preferably 5-30% of the amount of carboxylic acid, i.e. 1-5% of the total amount of polymer). Examples of hydrophobic vinyl monomers include alkyl acrylates, methacrylates, alkyl acrylamides, alkyl methacrylamides, styrene and derivatives thereof, and carboxylic acid esters of vinyl alcohol, and these may be used in combination. . Examples of carboxylic acid-containing vinyl monomers include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, half esters thereof, and the like.
30% by weight, preferably 3-20% by weight. Particularly preferred hydrophobic monomers include propyl acrylate, butyl acrylate, butyl methacrylate, hexyl acrylate, etc., which have a low Tg. In addition to the above monomers, the latex of the present invention contains sulfonic acid-containing monomers (up to 1% by weight, such as 3-methacryloyloxypropane-1-sulfonic acid sodium salt, 2-acrylamide-2-
sodium methylpropanesulfonate, etc.), monomers containing active methylene (10 or less by weight)
(for example, acetoacetoxyethyl methacrylate), and furthermore, a small amount (5% by weight or less) of crosslinking monomers such as N-methylolacrylamide and glycidyl methacrylate can be used as a copolymerization component. Addition of active methylene monomer (10% or less) has the function of suppressing fog and promoting hardening, and adding sulfonic acid monomer in large amounts will make polymerization unstable, but adding a very small amount (1% or less) has the effect of increasing the PKa of carboxylic acids incorporated into latex. Depending on the nature of the photographic additive to be filled, monomers exhibiting weak hydrophilic properties such as methacrylonitrile, acrylonitrile, hydroxyethyl acrylate, and diacetone acrylamide (0 to 50
(% by weight) copolymerization component may be better for loading photographic additives and compatibility with gelatin. After polymerizing the latex, bases used to neutralize a portion of the carboxylic acid include alkali metal bases such as sodium hydroxide, potassium hydroxide, potassium carbonate, and sodium bicarbonate, ammonia, methylamine, ethylamine, trimethylamine, and tetrahydroxide. Organic bases such as methylammonium can be used. Hereinafter, typical latexes of the present invention will be illustrated, but the present invention is not limited thereto. still,
Numbers indicate weight %. Actually, after polymerizing the latex illustrated here,
Neutralization is performed and part of the carboxylic acid is used as the sodium salt. <Exemplary latex> 1 Poly(butyl acrylate 91%, acrylic acid 9%) 2 Poly(butyl acrylate 60%, styrene 30%)
%, acrylic acid 10%) 3 Poly (60% butyl acrylate, 30% methacrylonitrile, 10% methacrylic acid) 4 Poly (80% propyl acrylate, styrene
10%, methacrylic acid 10%) 5 Poly(butyl methacrylate 70%, butyl acrylamide 15%, methacrylic acid 15%) 6 Poly(ethyl acrylate 30%, butyl acrylamide 20%, butyl methacrylate 45
%, itaconic acid 5%) 7 Poly(butyl methacrylate 50%, styrene 40%, methacrylic acid 5%, maleic acid half-butyl ester 5%) 8 Poly(butyl acrylate 90%, acrylic acid 9%, 2-acrylamide -2-Sodium methylpropanesulfonate 1%) 9 Poly(butyl acrylate 86%, diacetone acrylamide 5%, methacrylic acid 9%) 10 Poly(styrene 60%, butyl acrylate 30
%, methacrylic acid 10%) 11 Poly (50% styrene, 30% propyl acrylamide, 15% methacrylonitrile, 5% acrylic acid) 12 Poly (60% propyl methacrylate, 30% styrene, acetoacetoxyethyl methacrylate 5 %, itaconic acid 5%) 13 Poly(vinyl acetate 95%, methacrylic acid 5%)
%) There are various oil-soluble additives that can be contained in the latex of the present invention, some of which are shown below. The present invention is not limited to this.

【formula】

【formula】

The latex of the present invention contains a wide variety of compounds, such as couplers, developer ultraviolet absorbers, scavengers, and DRR compounds. It is particularly effective for loading compounds, scavengers, etc.). Phenol derivatives, naphthol derivatives, 5-pyrazolone derivatives and acylacetamide derivatives are well-known as couplers, but other structures may of course be used. It also includes those that are colored themselves, such as colored couplers, those that become colorless compounds through a coupling reaction, and those that release special effects through a coupling reaction, such as DIR couplers. Examples of the developer include hydroquinone derivatives, P-phenylenediamine derivatives, and 1-phenyl-3-pyrazolidone derivatives. Scavengers for deactivating excess oxidized developer include hydroquinone derivatives with ballast groups and 1-phenyl-3-pyrazolidone derivatives. Furthermore, substances suitable for being filled and dispersed with the latex of the present invention include dye developers and DRR compounds used in instant photography. DRR compounds (dye-releasing redox compounds)
Dye Releasing Redox compound) is, for example, a ballasted phenol (or naphthol) o
Alternatively, a dye is bound to the p-position through a sulfonamide, or a dye is bound to the 3-position of the indole through a sulfonamide, etc., which also react with the oxidized form of the phenidone derivative during development. Thus, it releases a diffusible dye. (Unexamined Japanese Patent Publication 1973-
33826, No. 51-104343, No. 54-130122, etc.) The latex (aqueous dispersion) of the present invention is particularly excellent in dispersing hydrophobic photographic additives that require elution or reaction during development. The amount of solid latex content per unit weight is large, and the loaded additives have sufficient reactivity (for example, couplers have high color development), and the color images formed are also robust. The film has good physical properties. A manufacturing example is shown below. Production Example 1 (Production of Exemplary Latex 1 of the Invention) After attaching a dropping funnel stirring rod to a 500 ml four-headed colben, 280 ml of distilled water was added thereto, and 0.7 g of sodium dodecylbenzenesulfonate was dissolved therein. Heat to ℃. 0.4 g of ammonium persulfate dissolved in a small amount of water separately
After quickly adding 0.4 g of sodium bisulfite, 60 g of n-butyl acrylate and 6 g of acrylic acid were added dropwise from the dropping funnel over 30 minutes. After the dropwise addition was completed, stirring was continued for 4 hours at 80°C, and then the mixture was cooled to stop the polymerization. When this was filtered, there were almost no aggregates (0.1 g or less).
The solid content concentration was 21.5%. After this raw latex was subjected to dialysis treatment for 3 days, it was diluted to a solid content concentration of 10%, and 0.2N sodium hydroxide was added dropwise to adjust the pH to 6.6. 17ml of 0.2N-NaOH per 100ml of latex
It took. This is 25% of the acrylic acid in latex.
indicates that it is dissociated. Production Example 2 (Production of Exemplary Latex 8 of the Present Invention) A dropping funnel stirring rod was attached to a 500ml four-headed kolben, and 250ml of water was added thereto to dissolve 0.7g of sodium dodecylbenzenesulfonate, and the mixture was heated at 80°C under a nitrogen atmosphere. Heat to. After quickly adding 0.4 g of ammonium persulfate and 0.4 g of sodium hydrogen sulfite individually dissolved in a small amount of water, 60 g of n-butyl acrylate, 6 g of acrylic acid dissolved in 30 ml of water, and 2
A mixture of 0.6 g of sodium -acrylamide-2-methylpropanesulfonate was simultaneously added dropwise over 30 minutes. After the dropwise addition was completed, stirring was continued for 4 hours at 80°C, and then the polymerization was stopped by cooling.
This was filtered to obtain a latex with a solid content concentration of 20.2%. (0.25 g of aggregate) After dialysis treatment in the same manner as in Production Example 1, it was diluted to 10% and neutralized to pH 6.8. 6.5 ml of 0.2N-NaOH was required per 100 ml of latex (10%). This indicates that 10% of the acrylic acid in the latex has been dissociated. Production Example 3 (Production of Comparative Latex-1) Using the same method as in Production Example 2, 3.0 g of sodium 2-acrylamido-2-methylpropanesulfonate was dissolved in 60 g of butyl acrylate and 30 ml of water.
Comparative latex-1 (95% by weight of butyl acrylate, 2-acrylamide-2)
- Sodium methylpropanesulfonate (5% by weight) was produced. Solid content concentration 19.5% aggregate is 1.20
It was hot at g. Production Example 4 (Production of Comparative Latex-2) Using the same method, a mixture of 60 g of butyl acrylate and 8.0 g of sodium 2-acrylamido-2-methylpropanesulfonate dissolved in 50 ml of water was simultaneously added dropwise to produce Comparative Latex-2 ( Butyl acrylate 88% by weight, 2-acrylamide-2-
Sodium methylpropanesulfonate 12% by weight)
was manufactured. The amount of aggregate with a solid content concentration of 18.5% was 2.5 g. Production Example 5 (Production of Comparative Latex-3) Using the same method as Production Example 2, 60 g of butyl acrylate, 6 g of acrylic acid, and 3.5 g of sodium 2-acrylamide-2-methylpropanesulfonate dissolved in 30 ml of water were added dropwise for comparison. Latex-3 (86% by weight of butyl acrylate, 9% by weight of acrylic acid, 5% by weight of sodium 2-acrylamide-2-methylpropanesulfonate) was produced. The amount of aggregate with a solid content concentration of 20.8% was 2.2 g. Production Example 6 (Production of Comparative Latex-4) By the same method as in Production Example 2, 60 g of butyl acrylate, 8.0 g of sodium acrylate dissolved in 50 ml of water, and 0.7 g of sodium bicarbonate were added dropwise to produce Comparative Latex-4 (butyl (89% by weight of acrylate, 11% by weight of sodium acrylate). The amount of aggregate with a solid content concentration of 20.5% was 2.1 g. As can be seen from the above examples, since the present invention polymerizes in a system containing few electrolyte monomers, there are fewer aggregates.
It is clear that latex can be produced stably. Next, an example in which the latexes of Production Examples 1 and 2 were subjected to neutralization titration will be shown to show how the latex of the present invention behaves during coating or development. <Neutralization titration of the latex of the present invention> The latex of Production Example 1 (after dialysis) was adjusted to a solid content concentration of 5%, and this was placed in a 50 ml beaker and 0.2N
- NaOH solution was added dropwise. Drop 0.5ml of alkali onto the latex,
Figure 1 shows the results of measuring the pH after a few minutes. Further, the neutralization behavior of the latex of Production Example 2 measured in the same manner is shown in FIG. As is clear from each figure, the latex of Production Example 1 has a PKa of 6.95, and the latex of Production Example 2 has a PKa of 7.5. At around PH 6.5, where it is mixed with gelatin and applied, most of its carboxylic acid is is found to be in a non-dissociated state. That is, the latex is made hydrophobic during filling and coating with photographic additives. Furthermore, the latex of Production Example 6 had a PKa of 5.8, which is thought to be because the carboxylic acid moieties in the latex were extremely oriented on the surface because acrylic acid was supplied in the form of Na salt. In this case, most of the carboxylic acids are thought to have dissociated into ions during coating, and the latex is also thought to have been made hydrophilic during filling with photographic additives and coating. The loading of photographic additives into latexes uses water-miscible organic solvents (tetrahydrofuran, acetone, alcohol, etc.) as co-solvents. At this time, it is made easier by adding a very small amount of a water-immiscible solvent such as ethyl acetate. Filling procedures include dissolving the photographic additive in a solvent and pouring the latex into it, or mixing the latex with an auxiliary solvent, adding the photographic additive to it, and stirring for a while. Although either method may be used to produce the latex of the present invention, the latter method is superior to the former method in that the amount of solvent can be reduced. In either method, by distilling off the organic solvent, the hydrophobic additive is completely transferred from the solution to the latex particles, and the dispersion is completed. The resulting dispersion of photographic additives is mixed with a conventional hydrophilic binder (gelatin, polyvinyl alcohol, etc.) to form a photographic coating liquid. Furthermore, since gelatin and the like have protective colloidal properties, mixing gelatin and a latex dispersion before distilling off the auxiliary solvent and then distilling off the solvent is also an excellent method in terms of suppressing agglomeration of the latex. The obtained photographic coating solution can be used for ordinary well-known silver halide photographic light-sensitive materials and is processed by well-known processing methods, but the latex for filling of the present invention can be used for processing at a pH of 9 or higher. It is especially effective when using liquid. Examples will be shown below, but the present invention is not limited thereto. Example 1 Each latex synthesized in Production Examples 1 to 6 was adjusted to PH6.6.
After neutralizing, dilute to 5% solid content and add 20ml of this.
Take in a beaker. To this was added 20 ml of a 1:1 mixed solvent of tetrahydrofuran-acetone, and then 0.5 ml of ethyl acetate. Add a predetermined amount (0.5 to 2.5 g) of magenta couplers (M-1 and M-2) to this mixed solution while stirring, and stir for a while. When the solid powder (coupler) disappeared, the organic solvent was distilled off under reduced pressure to obtain a coupler-filled latex liquid. Example 2 Of the coupler-filled latex liquid obtained in Example 1, one with C/L=1 (coupler weight/latex solids weight) was mixed with a green-sensitive silver halide emulsion and spread on a polyester support. It was applied to have the following composition. Coupler 6 mg/100 cm ² Silver bromide (3.8 mg/100 cm ² in terms of silver) Gelatin 12 mg/100 cm ² After exposure through a silver wedge, color development was performed according to the following processing steps. Processing () Processing process (38℃) Processing time Color development 3 minutes Bleaching 5 minutes 30 minutes Washing with water 3 minutes Fixing 5 minutes Washing with water 4 minutes [Color developer composition] 4-Amino-3-methyl-N-ethyl -N-
(β-hydroxyethyl)-Aniline sulfate 4.8g Anhydrous sodium sulfite 4.3g Hydroxylamine 1/2 sulfate 2.0g Anhydrous potassium carbonate 37.0g Sodium bromide 1.3g Potassium hydroxide 1.0g Add water to make 1, potassium hydroxide Using
Adjust to PH10.0. [Bleach solution composition] Ethylenediaminetetraacetic acid iron ammonium salt
100.0g Ethylenediaminetetraacetic acid diammonium salt
10.0g Ammonium bromide 150.0g Glacial acetic acid 10.0ml Add water to adjust to 1 and use ammonia water to pH
Adjust to 6.0. [Fixer composition] Ammonium thiosulfate (50% aqueous solution) 162ml Anhydrous sodium sulfite 12.4g Add water to make 1, and adjust to PH6.5 using acetic acid. Further, in the color development step in treatment (2), a color developer to which benzyl alcohol was added at an additional 10 ml/1 was used to conduct treatment (2). The maximum concentration was determined and the results are shown in Table 1.

[Table] As is clear from Table 1, the latexes of the present invention (Production Examples 1 and 2) have a large amount of coupler loading, sufficient color development, and do not require as much benzyl alcohol. On the other hand, in Production Example 3, the amount of coupler filled was satisfactory at C/L=3/2, but the color development was poor and almost no image was formed unless benzyl alcohol was added. In Production Example 4, on the other hand, the color development is sufficient, but the coupler filling rate is low. Production Example 5 is not much different from the present invention in terms of filling rate and color development, but as mentioned earlier, there are difficulties in synthesis. In Production Example 6, the latex of the present invention (Production Example 1) and acrylic acid were only changed to sodium acrylate salt, but the coupler filling rate was low. Example 3 The latex synthesized in Production Example 1 was neutralized to pH 6.5, diluted to a solid concentration of 3%, and placed in a 200 ml beaker. To this was added 200 ml of tetrahydrofuran, and then 2 ml of ethyl acetate. Add the following DRR compounds (DRR1 to 3) to this mixture while stirring.
Added 5.0g. After stirring for about 10 minutes, it becomes a clear solution. Then, most of the tetrahydrofuran was evaporated to obtain a DRR compound-filled latex liquid. Example 4 A photosensitive element was prepared by sequentially coating the following layers on a transparent polyethylene terephthalate film support having a thickness of 110 μm. In addition, for each layer below, the numerical values in parentheses are the coating amount of the material unless otherwise specified. (1) Styrene and N,N-dimethyl-N-benzyl-N-p-(methacryloylaminophenyl)
Terpolymer of methylammonium chloride and divinylbenzene (48/48/4 in molar ratio)
(27mg/ ^100cm2 ), the following fluorescent brightener (0.4mg/100cm2)
cm ² ) and gelatin (27 mg/100 cm ² ) (2) Light-reflecting layer (3) of titanium dioxide (230 mg/100 cm ² ) and gelatin (22 mg/100 cm ² ) Carbon black (25 mg/100 cm ² ) and gelatin (17 mg/100 cm ² ) opacifying layer (4) DRR compound 3 (4.0 mg/100 cm ² ) filled latex (4.8 mg/100 cm ² ) (produced in Example 3)
and cyan DRR of gelatin (11.0 mg/100 cm ² )
Compound layer (5) Red-sensitive internal latent image type direct positive silver bromide emulsion (10 mg/100 cm ² in terms of silver), potassium 2-sec-octadecylhydroquinone-5-sulfonate (1.4 g per mole of silver) ), 1-[4-(2-formylhydrazino)phenyl]-3-phenylthiourea (1.2 mg per mole of silver), and gelatin (15.5 mg/100 cm ² ) red-sensitive silver halide emulsion layer, (6) 2,5-di-sec-dodecylhydroquinone (4.5mg/100cm ² ), dibutyl phthalate (2.25mg/
100cm ² ), and an intermediate layer of gelatin (10.0mg/100cm ² ) (7) DRR compound 1 (4.6mg/100cm ² ), filled latex (5.52mg/100cm ² ), and gelatin (11.5
mg/100cm ² ) Magenta DRR compound layer (8) Green-sensitive internal latent image type silver bromide emulsion (8 mg/100cm ² in terms of silver) Potassium 2-octadecylhydroquinone-5-sulfonate (1 mole of silver) Hit
1.4g), 1-[4-(2-formylhydrazino)phenyl]-3-phenylthiourea (silver 1
1.2g per mole) and gelatin (13mg/100cm ² )
Green photosensitive silver halide emulsifier layer (9) 2,5-sec-dodecylhydroquinone (4.5
mg/100cm ² ), dibutyl phthalate (2.25mg/100
cm ² ), and an intermediate layer (10) of gelatin (10.0 mg/100 cm ² ), DRR compound 2 (5.6 mg/100 cm ² ), filled latex (6.72 mg/100 cm ² ), and gelatin (12 mg/100
cm ² ), a yellow DRR compound layer (11) consisting of a blue-sensitive internal latent image type bromide emulsion (8 mg/100 cm ² in terms of silver), potassium 2-octadecylhydroquinone-5-sulfonate (per mole of silver)
1.4g), 1-[4-(2-formylhydrazino)phenyl]-3-phenylthiourea (silver 1
per mole, 1.2 mg) and gelatin (13 mg/100
cm ² ) blue-sensitive silver halide emulsion layer (12) Tetrakis(vinylsulfonylmethyl)methane (2 mg/100 cm ² ) and gelatin (9 mg/100
Protective layer consisting of cm ² ) A photosensitive element was produced as described above. Separately, a treated sheet was prepared by sequentially coating the following layers on a 100 μm thick transparent polyethylene terephthalate film support. (a) Neutralizing layer with a copolymer of acrylic acid and butyl acrylate (70/30 weight ratio) (200 mg/100 cm ² ) (b) Cellulose diacetate (degree of acetylation 55 mol%) (57
mg/100cm ² ) and a copolymer of styrene and maleic anhydride (1:1) (4.5mg/100cm ² ), and 5-(2-phenylsulfonyl-ethylthio)-1-phenyltetrazole (3.4mg /100
( ^c ) terpolymer of vinylidene chloride, acrylonitrile and acrylic acid (polymerization ratio of 79/15/6)
(d) 4-Hydroxymethyl-4-methyl-1-p with (21 mg/100 cm ² )
-Tolyl-3-pyrazolidone (2.5mg/100
cm ² ), filled latex (3 mg/100 cm ² , Production Example 1)
A developer layer consisting of gelatin (8 mg/100 cm 2 ) and gelatin (8 mg/100 cm ² ), which was filled using a latex of A pot containing an alkaline processing composition is deposited and the pot is ruptured by passing between a pair of pressure rollers to spread the processing composition in the pot between the photosensitive element and the processing sheet. Processed. After a few minutes at 23°C a good color image was obtained. <Alkaline treatment composition> Potassium hydroxide 75g Sodium hydroxide 5.0g Sodium sulfite 2.0g 5-methylbenzotriazole 4.0g 2-tert-butylhydroquinone 0.1g 2-methylhydroquinone 0.1g cyclopentanol 1.5ml Carboxymethylcellulose sodium salt
60.0g Carbon black 171g Add water to make 1

[Brief explanation of the drawing]

FIG. 1 shows the neutralization behavior of the latex of Production Example 1, and FIG. 2 shows the neutralization behavior of the latex of Production Example 2.

Claims (1)

[Scope of Claims] 1. A polymer aqueous dispersion (latex) containing at least one monomer unit represented by the following general formulas (), (), and () as constituent components, containing a photographic additive. A method for dispersing photographic additives, characterized by dispersing them. General formula () (-A-) _x [wherein A represents a vinyl monomer containing carboxylic acid, and x is 2 to 30% by weight based on 100% by weight of the polymer. ] General formula () (-B-) _y [In the formula, B represents a vinyl monomer containing an alkali metal salt or an organic salt of carboxylic acid, and y is 0.5 to 8% by weight based on 100% by weight of the polymer. ] General formula () (-C-) _z [In the formula, C represents a hydrophobic vinyl monomer,
z is 50 to 95% by weight based on 100% by weight of the polymer. ]