Triarylmethane dyes, photographic recording materials, a process in which they are used, and methods for forming triarylmethane dyes.

摘要

Novel compounds are disclosed which have the formula <CHEM> wherein A is a phenyl moiety or a naphthyl moiety; B is a 4 min -oxo-1 min -phenyl moiety or 4 min -oxo-1 min -naphthyl moiety and X is a non-nucleophilic group that cannot add to the central carbon atom but in alkaline solution undergoes an irreversible cleavage reaction with base to provide a nucleophilic moiety that adds to the central carbon atom to form a ring-closed compound which is colourless. The compounds may be included in photographic products comprising a support, at least one photosensitive silver halide emulsion layer and a layer containing the coloured compound and during development of such products with an aqueous alkaline processing composition the group X cleaves to form a ring closed colourless compound.