Patent · US Expired

Electrophotographic method for the formation of two-colored images

US4524117A · kind A · utility

8Cited by
2References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 15, 1984
Grant dateJun 18, 1985
Priority date
Expiry dateJun 15, 2004

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G13/01
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An electrophotographic method for the formation of two-colored images comprising: (1) uniformly charging the surface of a photoreceptor having a conductive substance and a photoconductive layer formed on the conductive substance, said photoconductive layer being sensitive to a first color, (2) exposing a two-colored original, to form on said photoconductive layer an electrostatic latent image, which corresponds to a second color region in the original, with the same polarity as the electric charges on the surface of said photoconductive layer, (3) subjecting the surface of said photoreceptor to a reversal development treatment by the use of a photoconductive color toner charged with the same polarity as the electric charges constituting said electrostatic latent image, to develop the non-charged region with the photoconductive color toner, (4) subjecting said electrostatic latent image to a normal development treatment by the use of an insulative toner having a color different from the color of said photoconductive color toner, and (5) charging the color toners on said photoconductive layer with a different polarity from the charging polarity in process (1) and simultaneously expos…

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