176573 ⎘
Multicolour photographic processes or agents therefor; Regeneration of such processing agents; Photosensitive materials for multicolour processes; Colour processes using colour-coupling substances; Materials therefor; Preparing or processing such materials; Substances liberating photographically active agents, e.g. development-inhibiting releasing couplers characterised by the linking group between the releasing and the released groups, e.g. time-groups
Sub-classes: