| abstract |
A process for the production of colored photographic images by the silver dye-bleach process by image-wise exposure and subsequent processing by developing the silver image, dye-bleaching and silver bleaching, it being possible, optionally, for the last two steps to be combined, silver fixing and washing, in which process dye-bleaching and/or silver bleaching is carried out in the presence of at least one bleach catalyst of the formula <IMAGE> In the formula, A and B are in each case the non-metallic atoms necessary to complete a benzene or pyridine ring, R1 and R3 are each hydrogen, hydroxyl, halogen, alkyl, carboxyl, carbalkoxy, carbalkoxyalkoxy, -CH2OH, -O(CH2)nOH, -O(CH2)2O(CH2)2OH, -CH2Cl, -CH2Br, -NR5R6, -CH2NR5R6, -O(CH2)nNR5R6, -CH2SO3M, -O(CH2)nSO3M or -SO3M, R2 and R4 are each hydrogen, hydroxyl, alkyl or alkoxy and R5 and R6 are each hydrogen or alkyl, M is hydrogen, an alkali metal, ammonium or alkylammonium and n is an integer from 2 to 4. |