Patent ID: 7384721
Filing Date: 2008-06-10
Classification: G03G

Abstract:
1. A toner for electrostatic image development, obtainable by a process comprising the steps of: (I) melt-kneading a raw material mixture comprising a resin binder, a releasing agent, and a colorant; cooling the melt-kneaded mixture; and pulverizing the cooled mixture; and (II) further pulverizing a pulverized product obtained in the step (I) in the presence of an external additive; and classifying the pulverized product, wherein the releasing agent in said step (I) comprises a wax having a melting point of from 65° to 100° C., and wherein the external additive in said step (II) comprises an inorganic oxide subjected to hydrophobic treatment having an average particle size of 4 nm or more and less than 20 nm (hereinafter referred to as an “inorganic oxide A”), and an inorganic oxide subjected to hydrophobic treatment having an average particle size of 20 nm or more and 100 nm or less (hereinafter referred to as an “inorganic oxide B”).