PREPARATION OF RADIATION SENSITIVE FLAT PLATY GRAIN EMULSION

摘要

PROBLEM TO BE SOLVED: To prepare an emulsion almost independently of a temperature change in sensitization. SOLUTION: In a process for depositing silver bromide on the grains of a host flat platy grain emulsion, (1) a silver salt solution is introduced into a dispersion medium at a sufficient rate to generate a new group of grains, (2) silver ions and bromide ions released from the new group of grains are deposited on the grains of the host flat platy grain emulsion by suspending the introduction of the silver salt solution for a sufficient time to dissolve the new group of grains by an aging stage and (3) the steps (1) and (2) are repeated 3-20 times until the amount of silver bromide deposited on the grains of the host flat platy grain emulsion attains to 5-50% of the total amount of silver constituting the emulsion. The objective radiation sensitive flat platy grain emulsion is thus prepared.