Emulsion polymerization process for dry positive toner compositions employs charge control agent as wetting agent

Claim 1

A process for preparing dry positively charged toner particles which comprises subjecting to an emulsion polymerization, or suspension polymerization in the absence of a surfactant, a toner resin and colorant, the resin being a styrene/n-butyl methacrylate copolymer, or a styrene butadiene copolymer, carbon black, and a charge control agent present in the amount of from 0.1% to about 10 weight %, the charge control agent being selected from cetyl benzyl dimethyl ammonium chloride, distearyl dimethyl ammonium chloride or cetyl pyridinium chloride, which charge control agent functions as a wetting agent in the polymerization process, and as a charge control agent for the toner resin, said charge control agent being permanently attached to the toner resin and uniformily dispersed in said resin thereby resulting in a toner composition having a positive uniform triboelectrostatic charge over a substantial period of time, improved particle to particle uniformity, a narrow charge distribution, and the substantial elimination of the leaching of the charge control agent from the toner resin the reaction being accomplished at a temperature of at least 50° C.