Patent ID: 9023573
Filing Date: 2015-05-05
Classification: G03G

Abstract:
1. A method for producing a toner for electrostatic-charge image development including toner particles in which the surfaces of core particles including a binder resin composed of a polyester resin are coated with shell layers, the method including steps (I) to (IV): (I): a core particle dispersion-preparing step of obtaining an aqueous dispersion (1) containing core particles including a binder resin composed of a polyester resin, where aqueous dispersion (1) contains an anionic or nonionic dispersant; (II): a mixing step of mixing aqueous dispersion (1) adjusted to a pH of 5 or less and an aqueous dispersion (2) containing resin fine particles to obtain an aqueous dispersion (3) containing the core particles and the resin fine particles; (III): a coating step of adjusting the pH of aqueous dispersion (3) to 6 or more and 10 or less, followed by heating of aqueous dispersion (3) to coat the surfaces of the core particles with the resin fine particles, thereby obtaining an aqueous dispersion (4) containing core particles coated with the resin fine particles; and (IV): a film-forming step of adjusting the pH of aqueous dispersion (4) to 5 or less, followed by heating aqueous dispersion (4) to transform the resin fine particles, with which the surfaces of the core particles are coated, into a film, wherein the shell layer is a resin composed of a copolymer of monomers including a monomer having a quaternary ammonium group and a (meth)acrylic monomer, and the molar ratio of units derived from the monomer having a quaternary ammonium group in the copolymer is 5 mol % or more and 35 mol % or less.