Patent ID: 6432605
Filing Date: 2002-08-13
Classification: G03G

Abstract:
A process of preparing toner particles for developing latent electrostatic images, wherein said toner particles i) contain at least one pigment as a colorant, ii) have a volume average diameter in the range 1-10 &mgr;m, with at least 95 percent of said particles having a diameter in the range 2-15 &mgr;m, and iii) are substantially free of contamination by liquid organic medium used to prepare said toner particles, comprising:a) dispersing a pigment and a charge control agent in a polyester macromer to form a macromer mixture; b) forming a dispersion of fine droplets of said macromer mixture in a liquid organic medium in which said macromer and resulting toner particles are substantially insoluble, in the presence of a dispersion stabilizing surfactant; c) maintaining the organic medium containing said fine droplets of macromer mixture at an elevated temperature for a time sufficient to polymerize said macromer in said macromer mixture; d) cooling said liquid organic medium containing polymerized pigmented macromer; and e) separating said liquid organic medium from said polymerized pigmented macromer to obtain toner particles.