BLACK NONMAGNETIC PARTICLE POWDER FOR HIGH RESISTANCE BLACK TONER AND HIGH RESISTANCE BLACK TONER USING THAT BLACK NONMAGNETIC PARTICLE POWDER

摘要

PROBLEM TO BE SOLVED: To obtain black nonmagnetic particle powder for a high resistance black toner having more excellent fluidity and black degree and excellent dispersibility in a binder resin. SOLUTION: The powder is black composite nonmagnetic particle powder having 0.06 to 1.0μm average particle diameter and consisting of hematite particle powder or hydrated ferric oxide particle powder coated with an organosilane compound prepared from an alkoxysilane or with a polysiloxane, and carbon black depositing on at least part of the coating. The total amount of the carbon black deposited is 26 to 55 pts.wt. to 100 pts.wt. of the hematite particle powder or the hydrated ferric oxide particle powder.