Silver halide emulsions having host crystals with guest crystals formed

Abstract

Disclosed is a novel silver halide emulsion containing silver chloride-containing crystal grains which are cubic or rectangular parallelepiped silver halide crystals containing 30 mol % or more silver chloride on the crystal surface and surrounded mainly by (100) crystal faces, where the silver halide crystal has a projection of another crystal part formed on at least one (100) surface of the six crystal faces thereof and starting from the (100) surface has a bottom surface, the projection crystal part has substantially the same halogen composition as that of the surface of the (100) face of the original cubic or rectangular parallelepiped silver halide crystal grain, and the adjacent projection crystal parts have a groove part therebetween which is parallel to the edge part of the original silver halide crystal grain. The projection crystal parts on the silver chloride-containing crystal grains in the emulsion are preferably formed in the presence of a crystal habit-controlling agent selected from the group consisting of a nucleic acid or decomposition products thereof, a mercaptotetrazole compound, a mercaptothiadiazole compound, a hydroxyazaindene compound, a dicarbocyanine compound and a merocyanine compound. Also disclosed is a silver halide photographic material having at least one light-sensitive layer which contains the silver halide emulsion having the above-mentioned silver halide crystal grains having one or more of the projection crystals parts on a support. The material preferably has a coupler capable of forming a dye by a coupling reaction with an oxidation product of an aromatic primary amine color developing agent in the light-sensitive layer.