Patent ID: 7955773
Filing Date: 2011-06-07
Classification: G03G

Abstract:
1. A toner for developing an electrostatic image, comprising a toner particle to which particles of an external additive A having a number average particle diameter of from about 7 nm to about 200 nm and particles of an external additive B having a number average particle diameter of from about 30 nm to about 4000 nm have been externally added; a ratio of the number average particle diameter of the particles of the external additive B to the number average particle diameter of the particles of the external additive A being in a range of from about 2 to about 20; the particles of one of the external additive A or the external additive B being particles having a core material covered with an organic material containing hydrogen and nitrogen; the particles of the other one of the external additive A or the external additive B being SiO the average sphericity of the particles of each of the external additive A and the external additive B being from about 0.6 to about 0.8; the SiO the organic material containing hydrogen and nitrogen comprising at least one of an amino resin, an amino-modified silicone oil, an amino-modified silane coupling agent, an amino-modified titanate coupling agent, an amino-modified aluminate coupling agent, an amino-modified fatty acid, an amino-modified fatty acid metal salt, an ester of an amino-modified fatty acid, and a rosin acid.