JPS6049299B2 - Photographic compositions containing sulfonate copolymers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to the production and use of acrylic-type latex copolymers to improve the physical properties of photographic layers containing hydrophilic colloids.

Hydrophilic colloids of proteins are known to be useful in many contexts, particularly those of photographic properties, because the diluted products that can be made therefrom are optically clear.

For example, gelatin or gelatin derivatives are representative of hydrophilic colloids that have been found to be useful in this regard. However, such colloids exhibit undesirable physical properties in certain applications.

These undesirable physical properties occur when colloids are mixed with or bulked up with one or more synthetic materials, such as synthetic polymers. Patent documents that solve various problems using polymers and colloids such as gelatin include: US Pat. No. 3,411,911 to Dykstra, issued November 19, 1966; No. 1 by Rees et al.
No. 3,536,491, issued October 27, 1971;
U.S. Pat. No. 3,628,957 to O) et al.; U.S. Pat. No. 370 to Smith, issued October 24, 1999.
No. 0456; Nagae, published on July 10, 197
U.S. Pat. No. 3,745,007 to ae et al.; 19745
U.S. Pat. No. 3,811,897 to Babbit et al., published April 21, 1969; British Specification No. 1351767 published on May 1st. Especially in 1956
Forer published on March 20th. Fowler, U.S. Pat. No. 2,739,137; Tong, U.S. Pat.
No. 28 of TOng, published on September 16, 1995.
No. 52386 describes a copolymer of an unsaturated aliphatic amide, an acrylic ester, and a styrene compound! The preparation of hydrosols from the above and their use in photographic emulsions to disperse color couplers and to improve the flexibility of gelatin and similar colloids is disclosed.

British patent no. The present invention relates to gelatin extenders of copolymers consisting of sulfoester monomers (containing active methylene groups) and sulfoester monomers.

This copolymer can be crosslinked through active methylene groups to provide stability to the gelatin binder. However, these copolymers were found to be prone to forming microscopic and macroscopic aggregates when treated with water-miscible or water-soluble solvents. Sulfoester monomers can be used for various purposes)
It has been copolymerized with other ethylenically unsaturated monomers.

In particular, acrylamide sulfonates are disclosed in U.S. Patent No. 29837 to Wilkins On, issued May 9, 1961;
No. 4; and 197, published on April 14th last year.
It has been homopolymerized or copolymerized with acrylonitrile for use in water-soluble films and textile fibers, as disclosed in U.S. Pat.

KIT et al., U.S. Pat. (including styrene) to produce copolymers useful in films and fibers that have high whiteness and an excellent affinity for basic dyes.

However, such documents do not mention any photographic uses of such polymers. Many latex polymers are used as extenders for gelatin.
In particular, Fowler U.S. Patent No. 2739
These latex polymers disclosed in TOng No. 2,772,163; and TOng No. 2,852,386 are capable of resisting gelatin-latex agglomeration and flocculation caused by salts and organic solvents. sensitive to analysis.

This agglomeration in the coating melt limits the stability of the melt and causes extreme filter clogging, as well as "Double-Ended Composition".
This results in coating defects commonly referred to as "edcOmets". Furthermore, because of this agglomeration, the partially used melt cannot be stored for later reuse. As a result, optimal flexibility in melt preparation and planning of emulsion coater use is wasted or lost. Therefore, there is a need for a latex polymer that is less susceptible to the above-mentioned problems and can be used as a gelatin extender.

Such polymers must be stable to organic solvents and dissolved salts commonly used in photographic emulsions.
According to the present invention, certain sulfonate-containing latex copolymers have traditionally been used for this purpose because they are very stable in the presence of organic solvents or dissolved salts when used with hydrophilic colloids. It is possible to create polymers that are more flexible than the polymers that have been used in the past. Moreover, the polymers thus produced have the surprising effect of significantly increasing the photographic speed and also providing improved contrast and further shifting the hue of color photographic materials. In one aspect, compositions useful in making the flexible coatings of the present invention are copolymers having a hydrophilic colloid and a glass transition temperature of less than or equal to 60°C, wherein the copolymer has a glass transition temperature of less than or equal to 60°C. about 70 weight percent ester of polymerized ethylenically unsaturated carboxylic acid monomer; about 2 to about 18
from about 10 to about 3 weight percent of polymerized vinylbenzene; and from about 2 to about 18 weight percent of a polymerized sulfonate monomer (before polymerization) of the formula: and the total amount of polymerized amide and sno-5-phonate monomers is about 2 weight percent or less of the weight of the total copolymer, where R is hydrogen or alkyl; R1 is alkylene and Y.

2 [However, R2 is an alkyl or hydrogen-substituted divalent amino or -+CH2 sho NO1 (herein,
m is O or 1; and x is hydrogen or a monovalent cation.

In another aspect, the photographic elements of the present invention comprise a support, on the support at least one silver halide emulsion layer, at least one hydrophilic colloid and a copolymer as described above [i.e., a glass transition temperature of 60°C. lower or 60
and from about 50 to about 7 weight percent of an ester of a polymerized ethylenically unsaturated carboxylic acid; from about 2 to about 1 weight percent of an amide of a polymerized ethylenically unsaturated carboxylic acid; from about 10 to about 3 weight percent. % of polymerized vinylbenzene; and about 2 to about 1 weight percent of a polymerized sulfonate monomer represented by general formula (1) above (before polymerization), such that the total amount of polymerized amide and sulfonate monomer is approx. 2 of the polymer weight
% copolymer] in an aqueous dispersion.

As mentioned above, in one aspect, compositions useful for making the flexible coatings of the present invention include a hydrophilic colloid and a colloid having a glass transition temperature below 60°C or 600°C.
C and from about 2 to about 18 weight percent of formula (1) (before polymerization), where m is O or 1; R is hydrogen or alkyl, preferably from 1 to 10. alkyl of carbon atoms, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl and their isomers; R1 is alkylene, preferably of 1 to 5 carbon atoms; such as methylene, ethylene, propylene, butylene, pentylene, hexylene,
It consists of an aqueous dispersion of a copolymer consisting of polymerized sulfonate monomers (heptalene, octalene, nonylene, decylene and their isomers, which can be substituted with various substituents). .

R1 is also 几. 2 [However, R2 is 1 ('' 1, 1, ., 4 (However, R3 is hydrogen or a branched or straight chain alkyl having 1 to 1 carbon atom, and R4 is 1 to w carbon atoms. branched or straight chain alkylene having carbon atoms, specifically amino having the same carbon atoms as shown above).

Moreover, R2 can also be -(CH2+-n-0- (however, n is an integer of 0 to 5). X is hydrogen or a monovalent cation, such as lithium, sodium,
Alkali metal cations such as potassium, rubidium, etc.; copper(1) and others known in the art. Examples of sulfonate monomers useful in making the copolymers described above are sodium 2-acrylamido-2-methylpropane sulfonate, sodium 2-acrylamido-2,2-dimethylpropane sulfonate, 2-methylacryl-2-methylpropane. Sodium sulfonate, 2-methacrylamide 2●Sodium 2-dimethylpropanesulfonate, 2-acrylamide 2-methylpropanesulfonic acid, 2-acrylamide 2-ethylpropanesulfonic acid, 2-acrylamide 2-ethylpropane sulfonate Sodium sulfonate, sodium vinyl sulfonate, potassium vinyl sulfonate,
Sodium 2-propenylsulfonate, r[J--ρ
As mentioned above, from about 50 to about 7 weight percent of the copolymers useful in the present invention can consist of esters of polymerized ethylenically unsaturated carboxylic acids.

Examples of such monomers are: methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, and other alkyl acrylates; 2-hydroxyethyl acrylate, 2-hydroxyethyl acrylate,
-Hydroxypropyl acrylate and other hydroxyalkyl acrylates; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n
-butyl methacrylate and other alkyl methacrylates; 2-hydroxyethyl methacrylate, 2-
Hydroxypropyl methacrylate and other hydroxyalkyl methacrylates (m- and p-vinylphenyl)acetic acid, m- and p-vinylbenzoic acid,
3-Acrylamido Esters of 3-methylbutanoic acid and other ethylenically unsaturated carboxylic acids. Alkyl esters of acrylic acid, such as methyl acrylate, ethyl acrylate, propyl acrylate, n-butyl acrylate, etc., are examples of preferred monomers.

Additionally, about 2 to about 1 weight percent of the copolymers of the present invention consist of amides of ethylenically unsaturated carboxylic acids.

Examples of such monomers are acrylamide, methacrylamide, N-inpropylacrylamide, N-(1
・1-dimenothyl-3-dimethylaminopropyl)acrylamide, Nt-butylacrylamide, diacetone acrylamide, etc. Furthermore, as mentioned above,
About 10 to about 3 weight percent of the copolymers useful in this invention consist of polymerized vinylbenzene.

Such monomers include styrene, vinyltoluene,
Included are alpha-methylstyrene, p-bromostyrene, p-t-butylstyrene, styrene sulfonic acid, sodium salts and other substituted styrenes. Examples of useful copolymers include n-butyl acrylate (40-6 weight percent), methacrylamide (4-15 weight percent), styrene (10-3 weight percent), and 2-acrylamide-2-methylpropanesulfone. copolymer of sodium acid (2:1 weight percent); poly(butyl acrylate tocostyrene-co-sodium vinylyl sulfonate-co-methacrylamide) (58.8:25
．． and poly(methylacrylate-to-styrene-co-acrylamide-sodium 2-methylpropanesulfonate) (58.8:25).

2:8:8 weight ratio).

The sulfonate monomers useful in making the copolymers of this invention are commercially available or may be obtained from U.S. Pat. No. 3332904 of LaCOMbe et al.
issue; and Mirror (M
No. 3,506,707, published by Iller et al.

As used herein, glass transition temperatures (Tg) are defined by Marcel Dekker..lnc., N.C., unless otherwise specified.
Y. 197O's "Techniques and methods for polymer evaluation"
niquesandMethOdsOfPOlymer
It was determined using a differential scanning calorimeter disclosed in "Evaluation On", Vol. 2.

The glass transition temperature of the copolymers described herein is less than or equal to 60°C, preferably from about -20°C to about +20°C. The molecular weight of the copolymers useful in this invention varies over a wide range, but ranges from about 1 Cf' to about 1 Cf'. Such copolymers preferably have an inherent viscocity of about 0.3 to about 0.9, more preferably about 0.4 to about 0.6, provided that 0.25y of polymer is dissolved in 100mL of acetic acid. (measured at 25°C). Inherent viscocity used here is calculated by the following formula. where μ(ITlll) is the inherent viscosity, μ(Rel) is the relative viscosity of the acetic acid solution of the polymer, and C is the concentration of the polymer per 100 cc of solution, grams (4)
．． 25). Latex copolymers useful in the present invention can be made by well known polymerization techniques.

The preferred methods include various emulsion polymerization methods, such as batch, semi-continuous and continuous polymerization methods. Preparation Example 1 illustrates one semi-continuous process for making latex copolymers by premixing the monomers with suitable surfactants in a hot tank to create a fully homogeneous monomer mixture. This mixture is then added to the aqueous solution of surfactant and catalyst in the reaction vessel. The addition time is 1 to 12 minutes, preferably 3 minutes. This can be varied to change the physical properties of the interpolymer, such as the molecular weight. The temperatures at which the polymers described herein are made can vary widely. This temperature depends on factors such as the particular monomer used, heating time, and the pressure used. However, the polymerization temperature is generally about 110
C., often within the range of about 50 to about 100.degree. The pressure used in the polymerization may be sufficient to maintain the reaction mixture in liquid form. However, pressures above or below normal pressure can also be used if this is advantageous. The concentration of polymerizable monomer in the polymerization mixture can vary widely, up to about 100 weight percent, but preferably:
From about 20 to about 7 percent by volume, based on the weight of the polymerization mixture. Catalysts suitable for use in the polymerization reaction include, for example, from about 0.1 to about 2.0%, based on the total weight of monomers. Free radical catalysts such as hydrogen peroxide, peroxydisulfate, cumene hydroperoxide, water-soluble azo-type initiators, and the like.

Redox polymerization systems employ conventional ingredients such as potassium persulfate and potassium metabisulfite and others known in the art. If necessary, the polymer can be separated from the reaction medium by freezing, salting out, precipitation or other methods suitable for this purpose. In some cases, it may be advantageous to incorporate from about 0.5 to about 4 weight percent of a surfactant or a combination thereof, based on the total weight of monomers, into the preparation of the copolymers of the present invention. be. Suitable wetting agents include nonionic, ionic and amphoteric types such as polyoxyalkylene derivatives, amphoteric amino acid dispersants, including sulfobetaines, and the like. Such wetting agents are described in U.S. Pat. No. 260, issued June 17, 1952.
No. 0831, U.S. Patent No. 22, issued February 3, 1942.
No. 71,623; U.S. Pat. No. 2,275,727, issued March 10, 1942; U.S. Pat. It is disclosed in US Pat.
DuPont's Duponol (DupOnOl) ME and 01
Commercially available surfactants such as Surf Actant 1 from MathiesOn are also effective. The composition of the present invention consists of an aqueous dispersion of the above-mentioned copolymer and a hydrophilic/sexual colloid, preferably a protein colloid.

Examples of such colloids include: gelatin, protein derivatives such as carboxymethylated proteins, colloidal albumin, cellulose derivatives,
Nopoly (vinylpyrrolidone) and other water-soluble polymers. This colloid usually accounts for about 10% of the weight of the total composition.
and about 9 percent heel volume. In preferred embodiments of the invention, the described compositions further comprise a photosensitive silver halide, such as silver chloride, silver bromide, silver chlorobromide, in an amount of about 30 to about 7 by weight of the total composition. , silver iodide, silver bromoiodide and mixtures thereof. Dispersions of photographic silver halide and the sulfonate copolymers described herein and hydrophilic colloids such as gelatin can be made by a variety of methods. For example, an aqueous gelatin dispersion of photographic silver halide can be mixed with an aqueous dispersion or solution of a sulfonate copolymer.
The photographic silver halide can also be precipitated in an aqueous dispersion or solution of the copolymer. In this case, the copolymer and another colloid that influences the dispersibility of the copolymer may or may not be used together. In this case, a water-soluble salt such as silver nitrate is mixed with a water-soluble chloride such as potassium bromide in the presence of this mixture. In another method, photographic silver halide is precipitated in an aqueous gelatin solution and then ripened using conventional methods known in the art. After ripening and before coating, an aqueous dispersion of the copolyester is added to the emulsion. The bulk of the dispersion thus produced can be increased by adding large amounts of copolymers and/or natural or synthetic colloids or other binder agents suitable for use in photographic silver halide emulsions. Generally, the concentration of copolyester in the compositions of the present invention is from about 10 to about 90 weight percent, more preferably from about 30 to about 60 weight percent, based on the total weight of the composition. When the composition is used in a photographic element in a layer other than the silver halide emulsion layer, such as a filter layer, an anti-halation layer, an anti-abrasion layer, an antistatic layer, a barrier layer, an image-receiving layer in a diffusion transfer method, etc. These can be used as sole vehicles or together with natural or synthetic colloids as described above. The compositions described herein can be applied to a variety of supports.

Such supports include polyethylene terephthalate,
cellulose acetate butyrate, polycarbonate,
Film bases such as polyolefins (eg, polyethylene, polypropylene) can be mentioned. When such a film base is used, the photographic product obtained can be used, for example, as a transparency. If desired, the composition can be coated onto an opaque support such as paper, polyolefin coated paper, eg polyethylene or polypropylene coated paper. They can also be colored with TiO2 and subjected to electron bombardment or corona discharge to improve emulsion adhesion. When such supports are used, color photographic prints can be obtained. Emulsions containing the copolymers described herein can be chemically sensitized with sulfur compounds, noble metal salts such as gold salts, or reductively sensitized with reducing agents.

The emulsion layers and other layers of photographic elements made in accordance with this invention can be hardened with suitable hardeners. Useful concentrations of hardeners are related to the amount of binder used and are known in the art. The dura layer has a melting point in water greater than about 65°C, preferably 90°C.
higher than ℃. The emulsion may also contain other additives, especially known additives useful in photographic emulsions, such as water-miscible and water-immiscible organic solvents, stabilizers or antifoggants,
Speed enhancers, soluble inorganic salts, absorbing dyes, plasticizers, etc. can be included. Sensitizers that give particularly good results to the photographic compositions disclosed herein are alkylene oxide polymers, which may be used alone or with other substances, such as those disclosed in U.S. Pat. No. 2,886,437. Quaternary ammonium salts such as or U.S. Pat.
This can be used in conjunction with mercury compounds and nitrogen-containing compounds such as those disclosed in No. 129 Unagi.

The compositions described herein are suitable for a variety of photographic compositions and elements, such as direct positive silver halide emulsions, X-line and other non-spectrally sensitized emulsions, orthochromatic, panchromatic and infrared sensitive emulsions, particularly merocyanine dyes, It can be used in emulsions sensitized with cyanine dyes, carbocyanine dyes, etc.

Additionally, these compositions can be used in emulsions consisting of color-forming substances or emulsions developed with solutions containing couplers or other color-forming substances. Furthermore, these methods utilize a photographic emulsion containing a developer such as hydroxybenzene or undeveloped silver halide in the non-image area of the negative to dissolve the underdeveloped silver halide and further add this to the first silver halide emulsion layer. It can also be used in emulsions used in diffusion transfer methods in which a positive image is produced by precipitation on an image-receiving layer in close proximity to an image-receiving layer. Such a method is described in U.S. Pat. No. 23,520 to ROtt.
No. 14, Land U.S. Pat. No. 254,318
No. 1, and US Pat. No. 3,020,155 to Yackel et al. The sulfonate copolymers disclosed herein are useful in photographic image transfer film units, such as those described in the following patents: U.S. Pat. No. 2,543,181;
No. 6; No. 3227550: No. 3227552: No. 3415695; No. 3415644; No. 34
15646; and 3635707; Canadian Patent No. 67408; Belgian Patent No. 7579 and Belgian Patent No. 7579ω (both issued on April 23, 1971); British Patent No. 904364 and Belgian Patent No. 840731
No.; and German Patent No. 224276? .

The compositions of this invention can be used in the individual layers of multilayer photographic elements, with the coated layers varying over a wide range, for example from about 0.001y to about 0.01y per square meter of support.
．． 5y1 is preferably about 0.05y to about 0.3y.

Such compositions are particularly useful in color reversal photographic elements.

However, the latex sulfonate copolymer incorporated therein helps reduce the brittleness of the layer and the shade shift of the element's dyes. This hue shift is a shift in the intensity and absorption maximum of the image dye in the multiple layers of a photographic element with a joint increase in speed and contrast compared to an element with the same multiple layers but without the sulfonate copolymer. It means to be done. Next, examples of the present invention will be described.

Production Example 1 Poly(butyl acrylate tocostyrene-2-acrylamide-2-methylpropanesulfonic acid sodium comethacrylamide (58.8:25.2:8.
0:8. (Calculation ratio) This polymer latex was produced as follows.

Distilled water (528q) and Duponol (DupOnOl)
■(Sodium lauryl sulfate surfactant; E.I.Du
pOntdeNemOursllnc trade name) (1.
7k9) into the reaction vessel. Ta.

The solution was thoroughly purged with nitrogen and then heated to about 90° C. with a slight nitrogen purge. A 1 volume percent aqueous solution of sodium 2-acrylamide 2-methylpropanesulfonate (132 kg); surfactant Duponol ME (1.7k9) and methacrylamide (13.3k9) was added to the head tank with gentle stirring. added.

Butyl acrylate (100 kg) and styrene (42.
5 kg) was then added to this and the monomer emulsion in the head tank was continuously stirred for 2 minutes. Potassium persulfate catalyst (a). 85k9) was added to the contents in the reaction vessel and then the emulsion in the head tank was added within 2 minutes after catalyst addition. Three portions of this emulsion were continuously added to the reaction vessel. The contents of the reaction vessel were maintained at 92-95°C during this time. After the reaction of the monomer emulsion, the contents in the reaction vessel were cooled to 85° C., and polymerization was continued for three cycles. After the reaction, lower the temperature to 75
The temperature was further lowered to 0.degree. C., and the remaining monomer was recovered by vacuum distillation.

After the latex thus obtained was cooled to room temperature, further distilled water (538k9) was added with stirring. The latex was strained through a thin, coarse cotton cloth and placed in a storage container. The latex made in this way is 1
It had 2.2% solids.

The separated polymer had an inherent viscocity of 0.78 (measured in acetic acid); a glass transition temperature of +2°C. Production Example 2 Poly(butyl acrylate tocostyrene-co-vinylsulfonate sodium-co-methacrylamide) (58.8:25.2:8:8
Weight ratio) This copolymer was produced in the same manner as in Production Example 1.

However, sodium vinylsulfonate was used as the sulfonate monomer instead of sodium 2-acrylamido-2-methylpropanesulfonate. The separated polymer has an inherent viscocity of 0.49 (measured in acetic acid) and a glass transition temperature of -1°C.
It was hot. Production Example 3 Poly(methyl acrylate, styrene, 2-acrylamide, sodium 2-methylpropanesulfonate, methacrylamide) (
This copolymer was prepared in the same manner as the copolymer of Preparation Example 1, using methyl acrylate in place of butyl acrylate (weight ratio of 58.8:25.2:8:8).

The isolated polymer had an inherent viscosity of 0.72 as measured in acetic acid and a glass transition temperature of 60°C. Example 1 Gelatin and poly(butyl acrylate, styrene, 2-acrylamide, sodium 2-methylpropanesulfonate, methacrylamide) (58.8:2)
5.2:8.0:8. This is a comparative example showing that the stability of the composition of the present invention is better than compositions outside the present invention.

Table 1 lists representative latex properties and stability test results for compositions comprising the sulfonate copolymer of Preparation Example 1, as described in US Pat.
Latex properties of a control latex composition consisting of poly(butyl acrylate-co-styrene-co-methacrylamide) (58.8:25.2:16 weight ratio) made by the method described in No. 137. This is a comparison of the test results. For light scattering, the latex copolymer was diluted 1:10 with distilled water.
This diluted latex was placed in a 1 cm cell and placed on a Beckman DU spectrophotometer. It was obtained by measuring the apparent absorbance of 546TW1.

The tolerance limits for gelatin-latex compositions for typical organic solvents used in photographic compositions, such as methanol, are 5q of gelatin, 70 mL.

The mixture of water, 207,711 methanol and 4.3 ml of latex was aged for 4 hours at 40'C, and the melt was then examined microscopically at 645x magnification to simulate a polymer agglomerate. . The field of view seen through a microscope is transparent to a fine background and a small amount visible to the naked eye! It is desirable that the particles have agglomerated particles. It is satisfactory if the tolerance limit for alcohol is 20 percent or more.
Tolerance limits for dissolved inorganic salts in the composition are determined by the method used for light dispersion after aging at room temperature for samples made from 97.5 Da latex and 2.5 Y representative salts, such as potassium bromide. It was measured with

A satisfactory salt tolerance limit is an increase in apparent absorbance of 50
% or less, and furthermore, it is shown by the fact that no agglomeration occurs. Furthermore, a similar test was conducted using poly(butyl acrylate styrene-3-acryloyloxypropane-1-sulfonic acid sodium salt-co-methacrylamide) (58.8:25.2:88 weight ratio),
This is similar to the copolymer described in Dykstra U.S. Pat. No. 3,411,911;
It was immediately flocculated by KBR solution.

Other copolymers that are not stable to KBR include poly(butyl acrylate styrene-co-styrene sulfonic acid, sodium salt-co-methacrylamide) (
58.8:25.2:88 weight ratio) and poly(butyl methacrylate-2-acrylamido-2-methylpropanesulfonate sodium) (84:8:8 weight ratio). These results demonstrate that the composition of the present invention comprising a sulfonate copolymer has better stability against alcohol and dissolved salts than conventional latex compositions. Examples 2-4 Compositions of latex polymers with varying amounts of sodium 2-acrylamido-2-methylpropanesulfonate monomer These are comparative examples.

Latex polymers containing varying amounts of sodium 2-acrylamide 2-methylpropanesulfonate and methacrylamide were made according to the method of Preparation Example 1.

Compositions of each copolymer were tested for alcohol and bromide salt tolerance limits using the method of Example 1.

At this time, for comparison, the copolymer poly(butyl acrylate tocostyrene-comethacrylamide) (58.8:25.2:16 weight ratio) described in U.S. Pat. No. 2,739,137 was used as a control latex composition. Using. The results are shown in Table H. These examples demonstrate that the stability of the compositions of the present invention to alcohol and dissolved salts is better than that of conventional control compositions.

Even small amounts of sodium 2-acrylamido-2-methylpropanesulfonate in the latex significantly increase the stability of the composition. Salt tolerance improves as the amount of sulfonate monomer in the interpolymer increases, yet the absorbance is low and no clumping occurs. Example 5 Stability testing of the copolymer of Preparation Example 3 This is a comparative example.

The copolymer of Preparation Example 3 was composed of poly(butyl acrylate tocostyrene-2-acrylamido-2-methylpropanesulfonate) (58.8:25.2:1) as shown in the test results in Table m. It has better tolerance to alcohol and salt solutions (lower absorbance and greater stability) than the control copolymer composition without methacrylamide (total weight ratio).

Claims (1)

[Scope of Claims] 1 An aqueous dispersion of a hydrophilic colloid and a copolymer having a glass transition temperature of 60° C. or lower, wherein the copolymer comprises: A 50 to 70 weight percent of an ester of a polymerized ethylenically unsaturated carboxylic acid monomer; ;B 2
from 10 to 18 weight percent of polymerized amides of ethylenically unsaturated carboxylic acid monomers; C from 10 to 30 weight percent of polymerized vinylbenzene monomers; and D from 2 to 18 weight percent of general formula (I).
(However, before polymerization) a polymerized sulfonate monomer; ▲ There are mathematical formulas, chemical formulas, tables, etc. and
R in the formula is hydrogen or alkyl; R^1 is alkylene and ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [However,
R^2 is selected from the group consisting of alkyl or hydrogen-substituted amino, or ▲ has a mathematical formula, chemical formula, table, etc. ▼ (where n is 0 to 5); m is 0 or 1
and X is hydrogen or a monovalent cation;
A photographic composition characterized by: 2. The composition according to claim 1, wherein the hydrophilic colloid is gelatin. 3. The composition according to claim 1, wherein the ester is an alkyl ester of acrylic acid. 4. The composition according to claim 1, wherein the amide is an amide of methacrylic acid. 5. The composition according to claim 1, wherein the vinylbenzene is styrene. 6 The sulfonate has the following formula: ▲Mathematical formula, chemical formula, table, etc.▼ (where R is hydrogen or methyl; R^2 is alkyl or amino substituted with hydrogen; and X is an alkali metal cation. The composition according to claim 1, which is represented by: 7. The composition according to claim 1, further comprising photosensitive silver halide.