Process for the production of a spheroidized toner powder.

摘要

A process for the production of a spheroidized toner powder suited for use in single-component toner development of electrostatic charge images is provided, said process comprising the following steps : (1) dispersing irregularly shaped thermoplastic resin particles containing magnetically attractable material in the presence of colloidal carbon particles having sizes below 100 nanometer in a carrier liquid being a mixture of water and a water-miscible solvent, (2) heating the dispersion with stirring to a temperature at which said resin particles do not melt but soften and acquire a spherical or substantially spherical shape, (3) cooling down the dispersion to a temperature at which the resin particles are no longer sticky, (4) separating the resin particles from the carrier liquid and surplus colloidal carbon by magnetic attraction means, and (5) drying the separated particles. r