Use of copolymers in the production of photographic emulsions and photographic materials

Claim 2

A photographic material comprising a support and at least one photosensitive silver halide emulsion layer on said support comprising a peptizing agent and at least one silver halide wherein the improvement comprises said photosensitive layer includes a peptizing agent comprised of a copolymer of at least the following polymerized compounds: (1) An allyl ammonium salt corresponding to the following formula ##STR14## in which R 1 and R 2 which may be the same or different, represent hydrogen; an aliphatic, araliphatic or cycloaliphatic radical which may be substituted, or R 1 and R 2 may together represent the atoms required to complete a 5- to 7-membered ring; R 3 , R 4 and R 5 which may be the same or different, represent hydrogen or an alkyl radical which may be substituted; An represents an anion and/or R 3 represents the radical (--CR 5 R 4 --NR 1 R 2 H) + An; (2) a monomer B containing at least one anionic group; and (3) at least 40 mole percent of a compound C which is acrylamide and/or methacrylamide; wherein the copolymer has a molecular weight of from 10,000 to 200,000 and the polymer is present in a quantity of from 500 mg to 500 g per mole of silver halide.

Claim 3

A process for the production of a photosensitive silver halide emulsion comprising precipitation of a silver halide by reacting a water-soluble silver salt and a water soluble halide in the presece of a peptizing agent or comprising dissolution and crystalization to form substantially insoluble silver halide grains from readily soluble silver halide grains in the presence of a peptizing agent wherein the improvement comprises said photosensitive emulsion includes a peptizing agent comprised of a copolymer of at least the following copolymerized compounds: (1) An allyl ammonium salt corresponding to the following formula ##STR15## in which R 1 and R 2 which may be the same or different, represent hydrogen; an aliphatic, araliphatic or cycloaliphatic radical which may be substituted, or R 1 and R 2 may together represent the atoms required to complete a 5- to 7-membered ring; R 3 , R 4 and R 5 which may be the same or different, represent hydrogen or an alkyl radical which may be substituted; An represents an anion and/or R 3 represents the radical (--CR 5 R 4 --NR 1 R 2 H) + An; (2) a monomer B containing at least one anionic group; and (3) at least 40 mole percent of a compound C which is acrylamide and/or methacrylamide; wherein the copolymer has a molecular weight of from 10,000 to 200,000 and the polymer is present in a quantity of from 500 mg to 500 g per mole of silver halide.

Claim 4

A process for the production of a photosensitive silver halide emulsion comprising precipitation of a silver halide by reacting a water-soluble silver salt and a water soluble halide in the presece of a peptizing agent or comprising dissolution and crystalization to form substantially insoluble silver halide grains from readily soluble silver halide grains in the presence of a peptizing agent wherein the improvement comprises said photosensitive emulsion includes a peptizing agent comprised of a copolymer of at least the following copolymerized compounds: (1) An allyl ammonium salt corresponding to the following formula ##STR15## in which R 1 and R 2 which may be the same or different, represent hydrogen; an aliphatic, araliphatic or cycloaliphatic radical which may be substituted, or R 1 and R 2 may together represent the atoms required to complete a 5- to 7-membered ring; R 3 , R 4 and R 5 which may be the same or different, represent hydrogen or an alkyl radical which may be substituted; An represents an anion and/or R 3 represents the radical (--CR 5 R 4 --NR 1 R 2 H) + An; (2) a monomer B containing at least one anionic group; and (3) at least 40 mole percent of a compound C which is acrylamide and/or methacrylamide; wherein the copolymer has a molecular weight of from 10,000 to 200,000 and the polymer is present in a quantity of from 500 mg to 500 g per mole of silver halide.

Claim 5

The process of producing a silver halide emulsion as claimed in claim 2 characterized in that in the copolymer based on the polymer as a whole, the proportion of the polymerised allyl ammonium salt and the proportion of polymerised compound B respectively make up from 5 to 30 mole percent, and in that compound B corresponds to the following formula: ##STR16## in which R 10 represents hydrogen, an alkyl radical which may be substituted by a carboxyl or alkyloxy carbonyl group or by a carbamoyl group which may itself be substituted; Y represents hydroxyl or an alkoxy or alkylamino radical which may be substituted by a solubilising group.

Claim 6

The process of producing a silver halide emulsion as claimed in claim 2 characterized in that in the copolymer R 1 represents hydrogen; C 1 -C 12 alkyl, allyl or cyanoethyl; R 2 to R 5 represent hydrogen; R 10 represents hydrogen or methyl; Y represents hydroxyl; and An represents chloride, sulphate, methane sulphonate, benzene sulphonate, p-toluene sulphonate, methane phosphonate, monoalkyl methane phosphonate or trifluoracetate.

Claim 7

The process of producing a silver halide emulsion as claimed in claim 2 characterized in that in the copolymer polymerized units of an alkyl acrylate and/or methacrylate are additionally present in a quantity of from 5 to 25 mole percent.

Claim 8

The process of producing a silver halide emulsion as claimed in claim 2 characterized in that in the copolymer sulphur-containing compounds are additionally present in the copolymer.

Claim 9

The process of producing a silver halide emulsion as claimed in claim 2 characterized in that in the copolymer compound A is allyl amine hydrochloride and compound B is acrylic acid and/or methacrylic acid and in that from 5 to 25 mole percent of butyl acrylate, based on the polymer, are present in polymerised form.