Process for the preparation of silver halide emulsion.

摘要

A process for the preparation of a silver halide emulsion comprising silver halide grains dispersed in a dispersing medium. The process comprises the steps of (1) forming host silver halide nuclei in the dispersing medium, (2) adding a halide solution to the silver halide nuclei to form a crystal defect which gives rise the formation of tabular grain, by forming at least one gap interface of halide composition in the nuclei by a halogen conversion reaction and (3) growing silver halide grains preferentially along the direction of edges of the grains to form tabular grains having an aspect ratio (diameter per thickness) of not less than 1.5 and {100} major faces. A difference in chloride content or bromide content between the halide composition of the host silver halide nuclei and the halide composition of the halide solution is in the range of 10 to 100 mol % or a difference in iodide content between the halide composition of the host silver halide nuclei and the halide composition of the halide solution is in the range of 5 to 100 mol %. <IMAGE>