Photographic material

Abstract

Abstract PURPOSE: To increase the surface area of particles and to improve photographic performance, especially photosensitivity, by preparing silver halide particles in a silver halide emulsion layer in such a manner that the particle has a laminar structure of two different layers spreading over the particle surface and the surface is selectively etched. CONSTITUTION: The silver halide particles in a silver halide emulsion layer have a laminar structure of two different layers spreading over the particle surface, and the particle surface is selectively etched to obtain a larger grain surface. The area near the surface layer comprising silver halide which is hardly dissolved is etched. Moreover, since the dissolved silver halide from the grain in the etching process is recrystallized in an oriented growing state on other grains or on another part of the same grain, the grain surface can be increased without losing silver halide in the emulsion. Thereby, photographic performances such as chemical ageing and spectral sensitization can be improved.

Inventors

• 👤 Wolfgang Schmidt
• 👤 ボルフガング・シユミツト

Bibliographic Details