PREPARATION OF ELECTROPHOTOGRAPHIC DEVELOPING TONER

摘要

PURPOSE:To obtain an electrophotographic developing toner particles small in average particle diameter and uniform in particle diameter by dividing a toner material dispersed in a liquid dispersing medium heated to a specified temperature or higher by applying shearing force. CONSTITUTION:The toner material is obtained by incorporating a toner component in a toner binder resin comprising a copolymer obtained by chemically combining 90-30pts.wt. of at least one of crystalline polymers each having a melting point of 40-120 deg.C with 10-70pts.wt. of at least one of amorphous polymers each having a glass transition point of >=0 deg.C. The toner particles small and uniform in particle diameter can be obtained by applying shearing force to the disperse phase obtained with high yield by dispersing the toner material into the liquid dispersing medium in a state heated to or above the temperature at which the toner material melts.