MANUFACTURE OF SILVER HALIDE EMULSION, SILVER HALIDE PHOTOGRAPHIC SENSITIVE MATERIAL, AND METHOD FOR SPECTRALLY SENSITIZING SILVER HALIDE

摘要

PROBLEM TO BE SOLVED: To provide a method for manufacturing a silver halide emulsion which is good in the lot reproducibility and suitable to scale-up, of a photosensitive material high in sensitivity and low in fog and by changing a silver potential between before and after the start of addition of a sensitizing dye. ;SOLUTION: The silver potential is changed in the course of the spectral sensitization before and after the start of addition of the sensitizing dye, for example, the total amount of the sensitizing dye is added instantly into the emulsion adjusted to the silver potential for retarding a sensitizing dye absorption speed in order to form an uniform distribution, thus permitting the sensitizing dye concentration distribution in the system to be prevented from being directly reflected as it is to the adsorption amount distribution in the grains. After that, the silver potential is changed from the initial value by the absolute value of 3-700mV and adjusted to the value for accelerating the sensitizing dye adsorption speed, thus permitting the sensitizing dye to bv uniformly adsorbed and the emulsion to be enhanced in contrast. The emulsion is lower in contrast a little by adjusting the silver potential at the time of the addition to a potential a little higher in the speed and adjusting to a potential higher in the adsorption speed, when the sensitizing dye has been uniformly diffused into the system.;COPYRIGHT: (C)1998,JPO