Patent · US Expired

Magnetic toner, process for producing magnetic toner, and image forming method

US6447968B1 · kind B1 · utility

14Cited by
13References
29Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 29, 1997
Grant dateSep 10, 2002
Priority date
Expiry dateDec 29, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G9/0839
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A magnetic toner for developing an electrostatic latent image has magnetic toner particles containing at least a binder resin, a magnetic powder and a wax component. The magnetic powder has magnetic iron oxide particles the particle surfaces of which have been coat-treated with an organic surface modifying agent. The magnetic iron oxide particles contain silicon element (Si) in an amount of from 0.4 to 2.0% by weight based on the weight of iron element (Fe) and the magnetic iron oxide particles have an Fe/Si atomic ratio of from 1.0 to 4.0 at their outermost surfaces. The magnetic toner particles have shape factors SF-1 and SF-2 as measured by an image analyzer, with a value of SF-1 of from 100 to 160, a value of SF-2 of from 100 to 140 and a value of (SF-2)/(SF-1) of not more than 1.0.

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