Patent ID: 8178270
Filing Date: 2012-05-15
Classification: G03G

Abstract:
1. A toner for development of electrostatic images, comprising colored resin particles containing a binder resin obtained by polymerizing a monovinyl monomer used as a main component of the polymerizable monomer, and a colorant, and an external additive, wherein (i) the external additive contains fine particles of an inorganic layered clay compound whose interlayer distance is 1.5 to 4 nm, (ii) the inorganic layered clay compound is an intercalation compound with a quaternary ammonium ion intercalated between layers of the inorganic layered clay compound, (iii) the fine particles of the inorganic layered clay compound have a number average primary particle diameter of 0.1 to 3 μm, and (iv) the surfaces of the fine particles of the inorganic layered clay compound are subjected to a hydrophobilizing treatment with a hydrophobilizing agent which is a silane coupling agent or silicone oil, and wherein the external additive further contains, in addition to the fine particles of the inorganic layered clay compound, (A) fine particles having a number average primary particle diameter of 3 to 18 nm, and (B) fine particles having a number average primary particle diameter of 20 to 200 nm, said fine particles (A) and (B) being, independently of each other, selected from the group consisting of fine silica particles and fine titanium dioxide particles.