Examples of the metal oxide, the organic resin particles, and the metal soap as the lubricant particles include a lubricant such as polytetrafloroethylenic florine resin or zinc stearate, polishing agent such as cerium oxide or silicon carbide, a flowability stimulator such as SiO2, TiO2, or any other inorganic oxide having surfaces hydrophobic-treated, caking inhibitor, and surfactant.