Advanced Process for Polyester Chemically Prepared Toner in Aqueous Phase

Abstract

In the full color laser printers and copiers, the performance features of high print speed, fine image quality and environmental friendliness are required. Therefore the special toner also has been required for high speed printing and fine image quality. Recently many chemically prepared toners have been proposed, and these toners are suitable to achieve small and narrow particle size distribution. But most of these toners use styrene acrylic resin, and only a few toners use polyester which is superior to styrene acrylic resin in low-energy fusing. The polyester chemically prepared toners remain a matter of improvement in the point of environment friendliness, due to the use of organic solvent in the manufacturing process.Previously we reported on a solvent-free polyester chemically prepared toner in aqueous phase by using several surfactants, but it is not desirable to prepare polyester emulsions for toner with a large amount of surfactant. In this study it is found that the combination of anionic surfactants and nonionic surfactants is effective for preparing the polyester emulsion. In addition, it is found that hydrolysis of the polyester resin during emulsification can be inhibited by controlling the pH for neutralization of carboxyl terminal groups of the polyester.