CYANINE DYES AND THEIR USE AS SPECTRAL SENSITIZERS IN DIRECT POSITIVE PHOTOGRAPHIC MATERIALS OF THE SPECTRALLY SENSITIZED TYPE

摘要

ABSTRACT OF THE DISCLOSURENew cyanine dyes, comprising at least one of the followingnuclei (or derivatives thereof):1) 2,3,3-trimethyl-5-phenyl-sulfonyl-indolenine;2) 2,3,3-trimethyl-5-benzoyl-indolenine;3) 1-aryl or alkyl-2-phenyl-5-phenyl-sulfonyl-indole;4) 1-aryl or alkyl-2-phenyl-5-benzoyl-indole,are desensitizers for silver halide negative emulsions anduseful electron acceptor spectral sensitizers for directpositive silver halide emulsions.