METHOD OF MAKING PHOTOGRAPHIC MATERIALS

1293367 Incorporating colour couplers into photographic materials EASTMAN KODAK CO 30 Oct 1969 [1 Nov 1968] 53149/69 Heading G2C A dispersion of a water-insoluble photographic colour coupler in a hydrophilic colloid binder is made by dissolving the coupler and a waterinsoluble polymer in an auxiliary solvent, dispersing the solution in the colloid binder and removing the solvent. The coupler dispersion is then added to a photographic silver halide emulsion and coated to form a colour material. Polymers specified are alkyl methacrylate or acrylate homopolymers or interpolymers of alkyl acrylates or methacrylates with e.g. acrylic acid, acryloxyalkane sulphonic acids, vinyl-pyridines, acrylamide and N-vinylpyrrolidone. Auxiliary solvents include CHCl 3 , butyl and benzyl alcohols and alkyl acetates.