TONER, AND IMAGE FORMING METHOD AND APPARATUS AND PROCESS CARTRIDGE USING THE TONER

摘要

A toner including toner particles including a binder resin, a colorant and a release agent, and an external additive including a first particulate inorganic material having a formula of Mg_xSi_yO_x+2y where each of x and y is an integer, and a number average secondary particle diameter of from 0.02 mum to 2 mum, wherein the first atomic ratio (Mg/Si) s in a surface portion of the first particulate inorganic material is not greater than (preferably less than) the second atomic ratio (Mg/Si)e in the entire first particulate inorganic material. Alternatively, a toner including toner particles including a binder resin and a colorant, and an external additive which includes a particulate inorganic material having a formula of Mg_xSi_yO_x+2y where each of x and y is an integer and which has a surface treated with a fatty acid.