Konishiroku Photo Industry Co., Ltd.

Syozi Matsuzaka

Takeo Koitabashi

Toshifumi Iijima

Tetsuya Harada

Tashifumi Iijima

A photographic emulsion containing composite crystals of (a) silver halide and (b) copper halide or a solid solution crystal of copper halide and silver halide is found to be sufficiently photosensitive and developable. In such a photographic emulsion, the amount of silver used can significantly be decreased.

Photographic emulsion containing copper halide host crystals

There are provided a photographic silver halide emulsion which comprises composite silver halide crystals consisting essentially of multi-faceted silver iodobromide crystals containing 15-40 mole % of silver iodide and silver halide crystals containing not more than 10 mole % of silver iodide, said silver halide crystals being combined as epitaxial silver halide crystals with said multi-faceted silver iodobromide crystals, at least half of the facetes of said multi-faceted crystals being substantially free of said epitaxial crystals and the amount of said epitaxial crystals being limited to not more than 75 mole % based on the total silver halide forming said composite crystals, a silver halide emulsion comprising silver halide grains consisting essentially of silver iodobromide containing 15-40 mole % of silver iodide substantially homogeneously distributed therein, and a process for preparing the same.

Growing community of inventors

Hino, Japan

Syozi Matsuzaka