method and nichtdiffundierenden of lipophilic kupplern with a alkylphenoxygruppe or alkoxyphenylgruppe in the alkylrest 10 to 20 carbon atoms is in a photographic silver halogenid emulsion

摘要

937,387. Photographic colour material. GENERAL ANILINE & FILM CORPORATION. May 26, 1961 [July 26, 1960], No. l9139/61. Class 98 (2). Lipophilic, non-diffusing colour couplers containing an alkylphenoxy group wherein the alkyl chain contains 10-20 carbon atoms are incorporated in silver halide emulsions by dissolving the coupler in a water-miscible organic solvent in the presence of at least one molar equivalent of an alkali metal hydroxide, forming an aqueous coupler solution by adding more water than the amount of solvent present and mixing this solution with an emulsion. A lipophilic coupler is defined as water insoluble and not containing any water-solubilising groups but which can be dissolved in a watermiscible organic solvent. Specified couplers are those of Specification 852,922 and preferred organic solvents are ethanol, propanol, isopropanol and dimethylformamide. In the example, a coupler of formula is dissolved in dimethylformamide containing sodium hydroxide. This solution is diluted with water, combined with an aqueous gelatin solution and then further diluted with water before being combined with a gelatin silver halide emulsion.