PRODUCTION OF TONER FOR DEVELOPING ELECTROSTATIC CHARGE IMAGE

摘要

PROBLEM TO BE SOLVED: To efficiently use a dispersion stabilizer without causing environmental pollution by recovering slightly water-soluble calcium phosphate used as the dispersion stabilizer, regenerating and reuti-lizing it as well as to obtain a toner having <=10μm average particle diameter and a sharp particle size distribution. SOLUTION: A polymerizable monomer compsn. contg. a colorant and an electrostatic charge controlling agent is dispersed in an aq. medium with a dispersion stabilizer and suspension polymn. is carried out to produce the objective toner. At this time, fine particles of slightly water-soluble calcium phosphate deposited by adding an aq. soln. of <=pH4 contg. at least phosphate ions and calcium ions to an aq. alkali soln. so that the pH of the alkali soln. is not reduced to <5 after the addition are used as the dispersion stabilizer.