Patent ID: 6794121
Filing Date: 2004-09-21
Classification: G03C

Abstract:
A method of spectrally sensitizing a silver halide emulsion comprising the following steps in the following ordera) providing a silver halide emulsion comprising tabular silver halide grains having an inner dye layer adjacent to the silver halide grain, said dye layer comprising at least one dye (Dye 1) that is capable of spectrally sensitizing silver halide, b) adding to the emulsion at least one dye (Dye 2) capable of providing a second dye layer adjacent to the inner dye layer, and c) adding to the emulsion a scavenger for oxidized developer, to form a silver halide emulsion comprising silver halide grains having associated therewith two dye layers, wherein the dye layers are held together by non-covalent forces or by in situ bond formation; the outer dye layer adsorbs light at equal or higher energy than the inner dye layer; and the energy emission wavelength of the outer dye layer overlaps with the energy absorption wavelength of the inner dye layer.