GB2093204A - Silver Halide Photographic Light-sensitive Material - Google Patents

Abstract

A black-and-white silver halide photographic material contains in an emulsion layer or other layer a polymer of a repeating unit: <IMAGE> wherein R is hydrogen, halogen or Cl-6 alkyl, M is hydrogen, alkali metal, alkaline earth metal or organic base, X is C1-6 alkyl, alkoxy or alkylamino or halogen, m=0, 1 or 2 and n=1 or 2. The polymer may be a copolymer with another unit having an unsaturated bond. The amount of polymer can be 0.01-99% of the gelatin and polymer in the layer. 14 polymers including copolymers are shown. Syntheses of monomers and polymers are given. The inclusion of the polymer reduces fading of latent image before development.

Description

SPECIFICATION Silver Halide Photographic Light-sensitive Material This invention relates to black-and-white silver halide photographic light-sensitive materials, and more particularly to black-and-white silver halide photographic light-sensitive materials in which latent image fading is prevented.

As is well known in the art, the formation of a silver image according to a silver halide photographic method requires two processes, namely, an imagewise light-exposure process to form a latent image, and a development processing process to convert the latent image thus-formed into a corresponding silver image.

The formation of a latent image results from extremely small changes in silver halide crystals when considered from a chemical standpoint, and the latent image itself is essentially unstable. Over a period from the time of the projection light-exposure process to the time of the development processing process, the intensity of the latent image is liable to decrease. This phenomenon is generally called "latent image fading". The progress of the latent image fading varies generally depending on the conditions under which an exposed light-sensitive material is stored; for example, when the exposed light-sensitive material is stored at a high temperature, and particularly under conditions of high temperature and high humidity, the latent image fading is generally significant, whereas when stored at a low temperature and low humidity it is generally less significant.

Therefore, one method for overcoming the disadvantages resulting from the latent image fading is to carry out the development processing immediately after the imagewise exposure, and a second method is to store the exposed light-sensitive material at a low temperature for a period between the exposure and the development processing. Although these methods are theoretically simpler, they may not be convenient to the user. Under the conditions of practical use, negative materials and reversal materials for photography are often allowed to stand at room temperature for several months after exposure before they are subjected to development processing. Even positive materials for duplication are some times allowed to stand for several months.

It is therefore desirable to devise a silver halide photographic light-sensitive material which is inherently less subject to fading of the latent image.

In order to obtain such light-sensitive materials, various methods have heretofore been proposed.

However, these known methods, for example, the method of using an aromatic compound substituted with a hydroxy group as described in West German Patent 1,107,508, the method of using a 1,3-dione as described in U.S. Patent 3,447,926, the method of using nitrilotriacetic acid as described in U.S.

Patent 3,318,702, the method as described in U.S. Patent 3,424,583, and the method as described in West German Patent 1,173,339 are not completely sufficient for this purpose.

It has also been found that the most preferred compound for this purpose is a sulfinic acid, a typical example being benzene sulfinic acid, as described in U.S. Patent 2,057,764. However, two severe problems are encountered when such a low molecular weight compound, as represented by benzene sulfinic acid, is added to a silver halide emulsion layer. The first problem is that such a low molecular weight compound readily diffuses into layers other than the emulsion layer, for example, a surface protective layer or an antihalation layer, since the compound is highly water-soluble and has a low molecular weight. Thus the concentration of the compound in the desired emulsion layer decreases.

As a result, a larger amount of the sulfinic acid compound than that theoretically required must be added to obtain sufficient effect in preventing the latent image fading. The second problem #is that the sulfinic acid group is a strongly nucleophilic group, as is generally well known in the field of organic chemistry.

Since any hardening agent which is added to gelatin in order to withstand the photographic layer against high temperature and rapid development processing is electrophilic, the nucleophilic sulfinic acid group readily reacts with the hardening agent, and thus the hardening of the binder in the photographic layer, which is a primary function of the hardening agent, is reduced. In a serious case, this can result in almost totally destroying the ability for high temperature development processing.

Furthermore, when a photographic light-sensitive material is subjected to development at a high temperature in an automatic developing machine, such as a photographic light-sensitive material for lithography, fog is sometimes formed during development; this phenomenon is called "aerial fog" in the art. In order to prevent aerial fog, a technique in which an anti-oxidant such as resorcin is added to a surface protective layer of a photographic light-sensitive material is known. However, this technique is not always sufficient.

Therefore, an object of the invention is to provide a black-and-white silver halide photographic light-sensitive material in which the fading of latent image is prevented.

Another object of the invention is to provide a black-and-white silver halide photographic lightsensitive material in which the fading of latent image in a desired layer is effectively prevented by the use of a compound which does not diffuse from the layer to which it is added.

A further object of the invention is to provide a black-and-white silver halide photographic lightsensitive material in which the physical properties of layers in a wet state (i.e., adhesion strength and scratching strength of a hydrophilic colloid layer in a wet state) are appropriately considered.

A still further object of the invention is to provide a black-and-white silver halide photographic light-sensitive material in which the increase of aerial fog is prevented.

An even further object of the invention is to provide a black-and-white silver halide photographic light-sensitive material in which hardening of binder in the photographic layer is not inhibited.

It has now been found that not only is latent image fading sufficiently prevented, but also the above-described disadvantages, namely, diffusion of the compound, decrease in the functioning of the hardening agent, and aerial fog, can be prevented by the use of certain high molecular weight benzene sulfinic acid compounds.

Thus, according to the invention there can be incorporated into a silver halide emulsion layer or other hydrophilic colloid layer a polymer containing at least 0.01 mol% of a repeating unit represented formula (I)

wherein R represents a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms, such as a methyl group or an ethyl group, or a halogen atom, such as a chlorine atom or a bromine atom; M represents a hydrogen atom, an alkali metal atom, such as a sodium atom or a potassium atom, an alkaline earth metal atom, such as a calcium atom or a magnesium atom, or an organic base, such as triethylamine; X represents an alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms, an alkylamino group having from 1 to 6 carbon atoms, or a halogen atom; m represents 0, 1 or 2; and n represents 1 or 2.

Particularly preferred is a polymer containing at least 0.01 mol% of repeating unit represented by formula (la)

wherein M represents a hydrogen atom, an alkali metal atom, an alkaline earth metal or organic base.

Polymers having a repeating unit according to formula (I) above include homopolymers produced by polymerizing a monomer represented by formula (II) below, copolymers produced by polymerizing a monomer represented by formula (II) with another monomer having at least one additionpolymerizable unsaturated bond, and polymers produced by introducing a sulfinic acid group at side chains of the polymer after polymerization, as well as derivatives of these polymers.

Formula (II) for the monomers is:

wherein the symbols are as defined above.

Specific examples of monomers represented by formula (II) are set forth below.

Of these compounds, a particularly preferred monomer is Compound (A). The Monomer (A) can be synthesized by the method described in Chemistry Letters, pp. 41 9-420, published by Japan Chemical Society (1976), and the synthesis of the Monomer is not limited to that particular method.

The other monomers can be synthesized by the general method described in Chemistry Letters, ibid., or by reduction with a reducing agent such as sodium sulfite followed by optional vinyl formation of the corresponding sulfonic acid chloride.

A polymer such as polystyrene may be used as a starting material for the polymer reaction that is carried out in the above-described method to produce a polymer including a repeating unit of formula (1).

Any monomer that has at least one addition-polymerizable unsaturated bond can generally be used as a monomer copolymerizable with the monomer of formula (II). Such addition-polymerizable unsaturated compounds include, for example, allyl compounds such as allyl esters (e.g., allyl acetate, allyl caproate, allyl caprylate, allyl laurate); vinyl ethers (e.g., methyl vinyl ether, butyl vinyl ether, hexyl vinyl ether, octyl vinyl ether); vinyl esters (e.g., vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl dimethyl propionate, vinylcyclohexylcarboxylate, vinylbenzoate, vinyl salicylate, vinyl chlorobenzoate); vinyl heterocyclic compounds (e.g., N-vinyl oxazolidone, N-vinylimidazole, Nvinylpyrrolidone, N-vinylcarbazole, vinyl thiophene, N-vinylethyl acetamide); styrenes (e.g., styrene, methylstyrene, dimethylstyrene, trimethylstyrene, ethylstyrene, diethylstyrene, isopropylstyrene, chloromethylstyrene, chlorostyrene); vinyl ketones (e.g., methyl vinyl ketone, phenyl vinyl ketone and methoxyethyl vinyl ketone); olefins (e.g., dicyclopentadiene, ethylene, propylene, 1 -butane, 1 -pentene, 1-hexene, 4-methyl-1-pentene); itaconic acids (e.g., itaconic acid, itaconic anhydride, etc.); halogenated olefins (e.g., vinyl chloride, vinylidene chloride, isoprene); unsaturated nitriles (e.g., acrylonitrile, methacrylonitrile); acrylic acids (e.g., acrylic acid, methyl acrylate); and methacrylic acids (e.g., methacrylic acid).

Of these addition-polymerizable unsaturated compounds, styrenes, vinyl heterocyclic compounds, vinyl ethers, vinyl esters, and olefins are particularly preferred.

The polymer that is used according to the present invention must contain at least 0.01 mol%, preferably at least 0.1 mol%, and more preferably at least 1 mol%, of the repeating unit represented by formula (I). If the polymer contains less than 0.01 mol% of the repeating unit of formula (I), it is not capable of preventing the latent image fading. The intended objects of the present invention can be obtained by using one or more polymers according to the invention in an amount of from 0.01 to 99 wt%, preferably from 0.1 to 50 wt%, and more preferably from 1 to 20 wt%, based on the sum of the solid content of gelatin and the polymer in the silver halide emulsion layer or other hydrophilic colloid layer (for example, surface protective layer).The polymer used in too small an amount is not very effective, and using an excessive amount ( > 99 wt%) of the polymer results in an undesirably viscous coating solution, and this may result in difficult application of the solution or gelatin, which then does not set. The polymers defined above preferably have a molecular weight of from 1,000 to 2,000,000, and more preferably from 10,000 to 500,000. A polymer having too low a molecular weight is not vers effective, and using a polymer having an excessively high molecular weight may result in an undesirably viscous coating solution.

Illustrative polymers that can be used in the present invention are set forth below, wherein the proportion of constituent monomers is indicated in terms of the molar ratio.

Gelatin which is used in a silver halide emulsion layer, a surface protective layer, etc., according to the present invention may be "alkali-treated (lime-treated)" gelatin or "acid-treated" gelatin, which is prepared by immersion in an alkali bath or an acid bath before extraction. Alternatively, an enzymetreated gelatin of the type described in Bull Soc. Sci. Photo. Japan, No. 1 6, p. 30 (1966) may be used.

Gelatin of low molecular weight may also be used which is partially hydrolyzed by heating in a water bath or by treatment with protease.

Part of the gelatin used in the present invention can be optionally replaced by colloidal albumin, casein, a cellulose derivative such as carboxymethyl cellulose or hydroxyethyl cellulose, a sugar derivative such as agar, sodium alginate or a starch derivative, a synthetic hydrophilic colloid such as polyvinyl alcohol, poly-N-vinyl pyrrolidone, polyacrylic acid copolymer or polyacrylamide or derivatives or partial hydrolyzates thereof. Alternatively, the gelatin may be partially replaced with a gelatin derivative which is obtained by treating and modifying the intramolecular functional amino, imino, hydroxy or carboxyl groups with a reagent having one group that is capable of reacting with such functional groups. A portion of the gelatin may also be replaced with a graft polymer wherein gelatin is bound to the molecular chain of another polymeric substance.

The present invention can be used with particular advantage as a method of preventing the latent image fading in a silver halide photographic light-sensitive material.

The silver halide emulsion used in the present invention is usually prepared by mixing a solution of a water-soluble silver salt (e.g., silver nitrate) with a solution of a water-soluble halogen salt (e.g., potassium bromide) in the presence of a solution of a water-soluble polymer, e.g., gelatin. Examples of the suitable silver halide are silver chloride, silver bromide and mixed silver halides such as silver chlorobromide, iodobromide and chloroiodobromide. These photographic emulsions are described in such publications as Mees, The Theory of the Photographic Process, 3rd Ed., Macmillan Co. (1966), and P. Glafikides, Chimie Photographique, Paul Montel (1957).

These photographic emulsions may incorporate therein various additives to prevent fog or a drop in sensitivity from occurring in the production, storage or processing of a photographic light-sensitive material. A great many such compounds are known, including 4-hydroxy-6-methyl-1 ,3,3a,7tetraazaindene, 3-methylbenzothiazole, 1 -phenyl-5-mercaptotetrazole, various heterocyclic compounds, mercury-containing compounds, mercapto compounds, and metal salts. Some specific examples of suitable compounds are mentioned in K. Mees, The Theory of the Photographic Process, 3rd Ed. (1966), pp. 344-349 by reference to the papers which first reported such compounds.

The photographic emulsion layer and other layers according to the present invention may incorporate therein one or more synthetic polymer compounds, such as a water-dispersed vinyl polymer of a latex type (such as polyalkyl acrylate), that increase the dimensional stability of the photographic material individually or in combination of different kinds of polymers. These compounds may be used in combination with hydrophilic water-permeable colloids.

The polymer in the present invention can be used in the photographic light-sensitive material together with a matting agent. A suitable matting agent is fine particles of a water-insoluble organic or inorganic compound having an average particle size of from 0.2 to 1 0 microns, and fine particles comprising polymethyl methacrylate or silicon dioxide are particularly prefered.

Examples of the gelatin hardener that can be used in the present invention include, for example, aldehydes (e.g., formaldehyde, glyoxal, glutaraldehyde, etc.) N-methylol compounds (e.g., dimethylolurea, methyloldimethylhydantoin, etc.), dioxane derivatives (e.g., 2,3-dihydroxydioxane, etc.), active vinyl compounds (e.g., 1 ,3,5-triacryloylhexahydro-s-triazine, bis(vinylsulfonyl)methyl ether, etc.), active halogen compounds (e.g., 2,4-dichloro-6-hydroxy-s-triazine, etc.) mucohalogenic acids (e.g.

mucochioric acid, mucophenoxychloric acid, etc.), isooxazoles, dialdehyde starch, 1-chloro-6hydroxytriazinylated gelatin, etc.

A photographic emulsion layer or other layers in the photographic light-sensitive material to which the polymer of the present invention is applied may contain one or more surfactants. Surfactants are primarily used as a coating aid, but they are sometimes used for other purposes, such as for effective dispersion, sensitization, improvement of the photographic characteristics, prevention of static, prevention of blocking, and the like.These surfactants include natural surfactants such as saponin, etc., nonionic surfactants such as alkylene oxide compounds, glycerin compounds, glycidol compounds, etc., cationic surfactants such as higher alkylamines, quaternary ammonium salts, pyridine -and other heterocyclic compounds, phosphonium compounds, sulfonium compounds, etc., anionic surfactants containing an acidic group such as a carboxylic acid, a sulfonic acid, a phosphoric acid, a sulfate ester group and a phosphate ester group, etc., and amphoteric surfactants such as amino acids, aminosulfonic acids, and sulfate or phosphate ester of aminoalcohol, etc.

Further disclosure regarding materials that can be applied to a silver halide photographic lightsensitive material according to the invention are described in Research Disclosure, Viol. 1 76, pp. 22- 28 (1978), e.g., preparation of silver halide, chemical sensitizers, antifoggants, spectral sensitizing dyes, polymer latexes, matting agents, brightening agents, surfactants, plasticizers, lubricants, antistatic agents, and supports.

When the polymer in the present invention is used, each layer of the photographic light-sensitive material can be applied by various known coating methods such as dip coating, air-knife coating, curtain coating, spray coating, and extrusion coating that uses a hopper as described in U.S. Patent 2,681,294. If desired, two or more layers can be applied at the same time according to the method described, for example, in U.S. Patents 2,761,791, 3,508,947, 2,941,898 and 3,526,528.

There is no particular limitation on the method of exposing and development processing a photographic light-sensitive material of the present invention, and if necessary, reference can be made to Research Disclosure, Vol. 176, pup.28~30 (1978) for a suitable method.

The biack-and-white silver halide photographic light-sensitive material according to the present invention provides a metallic silver image as the finally obtained image and includes, for example, black-and-white film for amateur use, X-ray film, film for lithography, black-and-white printing paper, aerial film, micro film, facsimile film, film or printing paper for phototypesetting, and the like.

The monomers used to prepare the benzene-sulfinic acid-containing polymers used in the present invention can be synthesized by the following illustrative methods, but the synthesis is by no means limited to these examples.

I. Synthesis of Sodium Salt of Vinyl Benzenesulfinic Acid (Compound A) 1-1. Synthesis of p-(P-bromoethylbenzene)sulfonyl Chloride A measured amount (84.3 g) of 30% fuming sulfuric acid was placed in a three-necked flask with a stirrer, and at a controlled temperature of 20 to 230C, a mixture of 58.8 g (0.32 mol) of commercial ,B-bromoethylbenzene and 26.1 g (0.636 mol) of acetonitrile was added to the flask dropwise.

Thereafter, the temperature of the reaction mixture was elevated to 40 to 450C, then 92.3 g (0.795 mol) of chlorosulfonic acid was added dropwise. Following the dropwise addition, the reaction mixture was held at 40 to 450C for a while until the reaction was terminated. The reaction mixture was poured into one liter of ice water, and the resulting crystals were filtered off, dried, and recrystallized from hexane. The resulting compound, having a melting point of 54 to 550 C, was obtained in a yield of 59%.

1-2. Synthesis of p-(P-bromoethylbenzene)sulfinic acid A measured amount (42.5 g) (0.15 mol) of the p-(,-bromoethylbenzene)sulfonyl chloride and 210 cc of glacial acetic acid were placed in a 500-cc three-necked flask, and under stirring, 12.8 g of zinc powder was added to the flask at 25 to 350C. Thereafter, the mixture was stirred for an hour at 350C, and after the addition of 128 ml of concentrated hydrochloric acid and 106 ml of water, the temperature of the reaction mixture was elevated to about 800 C. When the contents were dissolved completely, the reaction mixture was cooled with ice, and the resulting crystals were filtered off and recrystallized from water.The resulting compound, having a melting point of 105 to 1 070C, was obtained in a yield of 42%.

1-3. Synthesis of Sodium Salt of Vinylbenzenesulfinic Acid (Compound A) A mixture of 12.7 g (0.051 mol) of the 2-bromoethylbenzenesulfinic acid,10.0 g (0.153 mol) of caustic potash, 237 ml of methanol and 0.14 g of hydroquinone was placed in a 500-cc three-necked flask and heated under reflux for an hour. Thereafter, the methanol was dried to form a solid which was mixed with 80 ml of water and 9 ml of concentrated hydrochloric acid. The resulting mixture was cooled with ice, and the crystals of vinylbenzenesulfinic acid was filtered off, dissolved in water, neutralized with caustic soda, and the water was distilled off to yield 60% of the desired product (Compound (A)) having a melting point of at least 2000C.

II. Synthesis of Sodium p-(a-methylvinyl)benzenesulfinate (Compound C) a-methylstyrene was treated with chlorosulfonic acid in the manner of Synthesis 1-1 to prepare p-(a-methylvinyl)benzenesulfonyl chloride. The chloride was reduced in the manner of Synthesis 1-2, and neutralized with caustic soda to obtain sodium p-(a-methylvinyl)benzenesulfinate having a melting point of at least 2000C in a yield of 36%.

Ill. Synthesis of Sodium Vinylbenzene-2,4-disulfinate (Compound E) According to Tr. Vses Nauch-lssed. lnst. Khim. Reactiv. Osobo. Chist. Khim. Veschestv, No. 33, p.

22~29, (1 971), a barium salt of 1 -(2-bromoethyl)benzene-2,4-disulfonic acid was reacted in a conventional manner with chlorosulfonic acid to form 1-(2-bromoethyl)benzene-2,4-disulfonic acid chloride. The chloride was reduced in the manner of Synthesis 1-2 to provide 1 -(2-bromoethyl)benzene-2,4-disulfinic acid, which was then vinylated in the manner of Synthesis 1-3 to form vinylbenzene-2,4-disulfonic acid.

A homopolymer of vinylbenzenesulfinate salt included in the formula (I) can be synthesized according to Chem. Lett, pp. 419--420, (1976). The polymer can also be prepared by any conventional polymerization method. Copolymers of vinylbenzenesulfinate salt can be synthesized by any known polymerization method, e.g., the method described in W. R. Sorenson s T. W. Campbell, Experimenting Synthesis Polymers (Tokyo Kagaku Dojin), pp. 147 and 1 57. The polymer can achieve the intended objects of this invention whether it is used as a solution in water or organic solvent or dispersion in water.

As already mentioned, a polymer having a repeating unit according to formula (I) can be prepared by polymerizing a monomer of the formula (II) or by introducing a sulfinic group into a separately prepared polymer. For example, a chlorosulfonated polystyrene can be prepared from polystyrene or poly(a-methylstyrene) in the manner of Synthesis l-1, and a polystyrene having a sulfinic group in the benzene nucleus can be produced in the manner of Synthesis 1-2.

Synthesis Example 1 Synthesis of Compound (1) A mixture of 30.0 g of sodium salt of vinylbenzenesulfinic acid and 1.5 g of potassium persulfate was dissolved in 300 cc of distilled water and the mixture in aqueous solution was polymerized in a nitrogen stream at 700C for 24 hours. Thereafter, the aqueous solution was dialyzed with distilled water for 24 hours and freeze-dried. The yield of the polymer was 22.6 g. It had an intrinsic viscosity rlsp /c (c=0.2 wt%) of 1.388 in a 1.5 mol aqueous solution of sodium bromide.

Synthesis Example 2 Synthesis of Compound (4) A mixture of 10.0 g of sodium salt of vinylbenzenesulfinic acid,5.83 g of N-vinylpyrrolidone and 0.570 g of the hydrochloride of 2,2'-azobis(2-amidinopropane) was dissolved in 200 cc of distilled water and subjected to polymerization in the same manner as in Synthesis Example 1. The polymer was obtained in a yield of 16.0 g.

Synthesis Example 3 Synthesis of Compound (7) A mixture of 15.0 g of sodium salt of vinylbenzenesulfinic acid, 5.8 g of potassium salt of vinylbenzenesulfonic acid and 0.570 g of the hydrochloride of 2,2'-azobis(2-amidinopropane) was dissolved in 200 cc of distilled water, and polymerization was performed in the same manner as in Synthesis Example 1. The yield of the polymer was 1 9.9 g. It had an intrinsic viscosity ii. sp /c (c=0.2 wt%) of 1.850 in a 1.5 mol aqueous solution of sodium bromide.

Synthesis Example 4 Synthesis of Compound (11) A mixture of 10 g of sodium salt of vinylbenzenesulfinic acid,1.13 g of vinyl acetate, and 0.356 g of 2,2'-azobisisobutyronitrile was dissolved in 200 cc of methanol and polymerized at 600C for 24 hours. The aqueous solution was then dialyzed with distilled water for 24 hours and freeze-dried.

Synthesis Example 5 Synthesis of Compound (12) Compound (11) was dissolved in dilute caustic soda, thoroughly hydrolyzed at 600C, dialyzed, and freeze-dried.

The present invention is hereunder described in greater detail by reference to the following examples.

Example 1 A silver iodobromide gelatin emulsion containing 6 mol% of silver iodide (average particle size of silver halide: 0.8 #), containing 270 g of silver iodobromide per 1 kg of the emulsion and 114 g of gelatin per 1 kg of the emulsion, was ripened by adding sodium thiosulfate and potassium chloroaurate.

To a part of the emulsion were added a compound used in the present invention or a comparison compound as described in Table 1 below and 4-hydroxy-6-methyl-1 ,3,3a,7-tetraazaindene as a stabilizer, sodium dodecylbenzenesulfonate as a coating aid, and 2,4-dichloro-6-hydroxy-s-triazine as a hardener, and the resulting mixture was coated on a cellulose triacetate support and dried to obtain Samples 1 to 10. These samples were exposed through an optical wedge using a sensitometer for 1/20 second. Then one set of these samples were stored in a refrigerator for 7 days and the other set of these samples were stored under the conditions of a temperature of 400C and a relative humidity of 70% for 7 days. Furthermore, still another set of these samples were stored under the conditions of a temperature of 500C and a relative humidity of 80% for 7 days, and then exposed in the same manner as described above.

These three sets of samples were developed with a Kodak (registered Trade Mark) D-72 developing solution at 200C for 4 minutes and fixed, washed with water, and dried in a conventional manner. The photographic properties (i.e., sensitivity and fog) were measured and the results thusobtained are shown in Table 1 below.

In Table 1, the photographic sensitivity is a reciprocal logarithm value of a light-exposure amount required to obtain an optical density of fog value+0.2, with the sensitivity of Sample 1 stored in the refrigerator being taken as 100, and the other sensitivities being shown relatively.

Table 1 Sensitivity after Storage of Latent Image Storage at 50 CC and 80% RH AmountAdded In At 40 0C Sample Compound (mol/molAgX) Refrigerator and 70% RH Sensitivity Fog 1 - - 100 80 68 0.12 2 Compound (1) 9x10-3 100 100 72 0.12 3 ,' 36x10-3 102 105 79 0.12 4 ,, 90x10-3 105 109 87 0.12 5 Compound (4) 9x10-3 100 100 71 0.12 6 ,, 36x10-3 98 105 79 0.12 7 ,' 90x10-3 96 107 93 0.13 8 Comparison* 9x10-3 100 96 76 0.15 Compound 9 ,, 36x10 100 100 68 0.16 10 ,, 90x 10-3 100 112 65 0.20 *Comparison Compound::

It is apparent from the results shown in Table 1 that the compound according to the present invention is advantageous in that the fog formation due to the storage under the conditions of high temperature and high humidity (i.e., at 500C and 80% RH) is relatively low, and latent image fading is prevented to a certain extent, in comparison with benzenesulfinic acid as described in U.S. Patent 2,057,764.

Example 2 To the same silver iodobromide gelatin emulsion as prepared in Example 1 were added a compound used in to the present invention or a comparison compound as described in Table 2 below and 4-hydroxy-6-methyl- 1 ,3,3a,7-tetraazaindene as a stabilizer, and sodium dodecylbenzenesulfonate as a coating aid. To the resulting mixture was added 2,4-dichloro-6-hydroxy-s-triazine as a hardener in an amount of 5 mmol per 100 g of dry gelatin. The thus-obtained mixture was coated on a cellulose triacetate support and dried to obtain Samples 11 to 13. Then, these samples were allowed to stand at room temperature for 1, 3, 7 and 15 days. The samples were measured for the swelling ratio (Q) in water at 250C determined according to the following formula: Increase in film thickness upon swelling 0= Thickness of dry film The results thus-obtained are shown in Table 2 below.

Table 2 Swelling Ratio {QJ Days after Coating Amount Added Sample Compound (mol/molAg) 1 3 7 15 11 - - 7.5 3.7 3.1 2.8 12 Compound (1) 90x10 7.4 3.9 3.3 3.0 13 Comparison* 90x 1 Oa 8.1 5.4 4.0 3.8 Compound *Comparison Compound:

It is apparent from the results shown in Table 2 that the compound according to the present invention has a less tendency of inhibiting hardening of gelatin in comparison with benzenesulfinic acid.

Claims (23)

Claims

1. A black-and-white silver halide photographic light-sensitive material comprising a support having thereon at least one light-sensitive silver halide emulsion layer, wherein at least one of the silver halide emulsion layer or other hydrophilic colloid layers contains a polymer containing at least 0.01 mol% of a repeating unit represented by the general formula:

wherein R represents a hydrogen atom, an alkyl group having from 1 to 6 carbon atoms or a halogen atom; M represents a hydrogen atom, an alkali metal atom, an alkaline earth metal atom or an organic base; X represents an alkyl group having from 1 to 6 carbon atoms, an alkoxy group having from 1 to 6 carbon atoms, and alkylamino group having from 1 to 6 carbon atoms or a halogen atom; m represents 0, 1, or 2; and n represents 1 or 2.

2. A silver halide photographic material as claimed in Claim 1, wherein R is a hydrogen atom.

3. A silver halide photographic material as claimed in Claim 1 , wherein R is a methyl group or an ethyl group.

4. A silver halide photographic material as claimed in Claim 1 , wherein R is a chlorine atom or a bromine atom.

5. A silver halide photographic material as claimed in Claim 1,2,3 or 4, wherein M is a hydrogen atom.

6. A silver halide photographic material as claimed in Claim 1,2,3 or 4, wherein M is a calcium atom or a magnesium atom.

7. A silver halide photographic material as claimed in Claim 1, 2, 3 or 4, wherein M is a sodium atom or a potassium atom.

8. A silver halide photographic material as claimed in Claim 1, 2, 3 or 4, wherein M is triethylamine.

9. A silver halide photographic material as claimed in Claim 2, wherein the repeating unit is represented by the general formula:

wherein M is as defined in any of Claims 1 or 5 to 8.

10. A silver halide photographic material as claimed in any preceding Claim, wherein the polymer is a copolymer.

11. A silver halide photographic material as claimed in Claim 10, wherein said copolymer contains a repeating unit derived from a monomer having at least one addition polymerizable unsaturated bond.

12. A silver halide photographic material as claimed in Claim 11, wherein said monomer is an ally ester, a vinyl ether, a vinyl ester, a vinyl heterocyclic compound, a styrene, a vinyl ketone, an olefin, an itaconic acid, a halogenated olefin, an unsaturated nitrile, an acrylic acid or a methacrylic acid.

13. A silver halide photographic material as claimed in Claim 10, 11 or 12, wherein said copolymer contains at least 0.1 mol% of the repeating unit of formula (I).

14. A silver halide photographic material as claimed in Claim 13, wherein said copolymer contains at least 1% of the repeating unit of formula (I).

15. A silver halide photographic material as claimed in any preceding Claim, wherein said polymer is present in an amount of from 0.01 to 99 wt% based on the total amount of gelatin and polymer present in the layer.

16. A silver halide photographic material as claimed in Claim 15, wherein said amount of polymer is 0.1 to 50 wt%.

17. A silver halide photographic material as claimed in Claim 16, wherein said amount of polymer is 1 to 20 wt%.

18. A silver halide photographic material as claimed in any preceding Claim, wherein said polymer has a molecular weight of from 1,000 to 2,000,000.

1 9. A silver halide photographic material as claimed in Claim 18, wherein said molecular weight is from 10,000 to 500,000.

20. A silver halide photographic material as claimed in any preceding Claim, wherein said polymer is present in a silver halide emulsion layer.

21. A silver halide photographic material as claimed in any preceding Claim, wherein said polymer is a polymer of any of monomers (1) to (14) shown hereinbefore.

22. A silver halide photographic light-sensitive material as claimed in Claim 1, substantially as hereinbefore described with reference to any of Samples 2 to 7 or 12 of the Examples.

23. A photograph made by imagewise exposure and development of a silver halide photographic material as claimed in any preceding Claim.