Patent · US Expired

Method of making an electrophotographic toner surface treated with metal oxide

US6200722A · kind A · utility

5Cited by
8References
20Claims
0Family size

Inventors

Key dates

Filing dateNov 30, 1999
Grant dateMar 13, 2001
Priority date
Expiry dateNov 30, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G9/09708
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A process for making an electrophotographic toner comprising: PA0 (a) uniformly mixing a metal oxide selected from titanium dioxide and silicon dioxide with toner particles to form a mixture having 5 to 15 weight percent metal oxide; PA0 (b) mixing the product of step (a) with additional toner particles at a mixing intensity .gtoreq.500,000 (cm/minute) minute; wherein in the mixed product of (b) the metal oxide is 0.1 to 5.0 weight percent of the mixed product; and the toner particles have on their surfaces a metal oxide concentration in a ratio of 1.0-3.0:1.0 with respect to titanium dioxide on the surface of the toner particles:total titanium dioxide in the mixed product; and a ratio of 10.0-25.0:1.0 with respect to silicon dioxide on the surface of the toner particles:total silicon dioxide in the mixed product.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.