METHOD FOR PRODUCTION OF MICROFINE COLORED PARTICLES AND ELECTROPHOTOGRAPHIC TONER USING THE PARTICLES

摘要

A method for the production of microfine colored particles, characterized by subjecting a polymeric monomer suspended in a suspension medium to suspension polymerization in the presence of a coloring agent and/or a magnetic powder thereby forming microfine globular colored particles possessing an average particle diameter in the range of from 3 to 50 .mu.m, heat treating said microfine globular colored particles with water as a heating medium at a temperature in the range of from 50.degree.C to 130.degree.C thereby inducing fusion of said particles and giving rise to blocks of fused particles, and then disintegrating said blocks of particles to an average particle diameter substantially equal to the average particle diameter of said microfine globular colored particles existent prior to said fusion.