Method for preparing silver halide emulsions and apparatus for implementing the method

摘要

A method and an apparatus for precisely controlling flow rate of reactant solution such as silver nitrate solution or halide salt solution which is added into a precipitation vessel. The method comprises applying a pressure to each source of said two solutions and controlling both said applied pressure and a flow resistance of each feed lines of said two solutions so that each flow rate of the two solutions to be added into the precipitation vessel can be adjusted to a predetermined value. The apparatus comprises a storage vessel for the reactant, a feed line to feed the reactant into the precipitation vessel and a flow rate controller, wherein the storage vessel is connected to a pressure controller which includes a pressure vessel pressurized with air or other gases and a pressure control valve, the feed line has a pressure sensor for detecting a pressure inside the feed line, a flow meter and a flow path opening controller along its line in order, the flow rate controller controls the flow rate of the reactant fed into the precipitation vessel by controlling the pressure control valve and the flow path opening controller.