Patent ID: 7569322
Filing Date: 2009-08-04
Classification: G03G

Abstract:
1. A method for producing a toner comprising: mixing and dispersing in an aqueous medium at least a resin particle dispersion in which resin particles are dispersed, a pigment particle dispersion in which pigment particles are dispersed, and a wax particle dispersion in which wax particles are dispersed, wherein the wax particles have a cumulative volume particle size distribution in which PR16 ranges between 20 and 200 nm, PR50 ranges between 40 and 300 nm, PR84 is not more than 400 nm in diameter, respectively, and PR84/PR16 is 1.2 to 2.0, where PR16, PR50, and PR84 are defined as particle sizes when a cumulative volume obtained by summing volumes of the wax particles successively from a smaller particle size side accounts for 16%, 50%, and 84% of the total volume (100%) of the wax particles, respectively; adjusting a pH of a mixed dispersion in which the resin particles, the pigment particles, and the wax particles are dispersed to 10 or higher and adding a water-soluble inorganic salt to the mixed dispersion; and producing aggregated particles by heating the mixed dispersion at temperature not lower than a glass transition point of the resin particles and then cooling, each of the aggregated particles comprising a core composed of an aggregate of the wax particles and aggregated particle layer that covers the core and comprises the resin particles that melted by the heating and the pigment particles, and whereby a resin film is formed on surfaces of the aggregated particles.