NEW DYE RELEASING COMPOUNDS AND THEIR USE IN PHOTOGRAPHIC SILVER HALIDE COLOUR MATERIALS FOR THE PRODUCTION OF COLOUR IMAGES BY A DYE DIFFUSION TRANSFER PROCESS

摘要

A photographic silver halide material comprises a shifted dye compound capable of releasing a dye moiety, characterized in that said compound corresponds in reduced state to general formula (1) and in oxidized state to general formula (2): A1-L-P(1) A2-L-P(2) wherein: A1 represents a hydroquinonyl group including a substituted hydroquinonyl group, or such group forming part of a fused ring system, A2 represents a quinonyl group including a substituted quinonyl group, or such group forming part of a fused ring system, L represents a bivalent group which undergoes a cleavage under hydrolytic alkaline conditions when the compound is in reduced state corresponding to formula (1), P represents an organic dye moiety incorporating an azo chromophoric group -N=N- linked through a conjugated bond system to an electron-withdrawing group being monoester oxalyl group wherein R represents an organic group, that can be introduced by esterification of a carboxylic acid group, said monoester oxalyl group being removable by hydrolysis resulting in a residual auxochromic hydroxyl (-OH) group.