Patent · US Expired

Electrophotographic method for producing black and color separation images

US4493881A · kind A · utility

2Cited by
1References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 20, 1983
Grant dateJan 15, 1985
Priority date
Expiry dateJun 20, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G5/12
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An electrophotographic method is disclosed for forming a black (or neutral) toner separation image and a color toner separation image from a single original without cross-contamination of black toner in the color separation image and vice versa. The method entails composing an original containing "false-color" information--other than black or neutral--corresponding to the black separation image desired and color information corresponding to the color separation image desired. The false-color and color information are selected to absorb actinic light in mutually exclusive wavelength regions of the spectrum. When the original is illuminated, for example, with light having wavelengths in the false-color absorption region only, a light pattern is formed and employed to expose a charged photoreceptor. The resulting electrostatic image is developed with black--or neutral--toner, thereby forming the black separation image. On the other hand, when the original is illuminated with light of wavelengths in the color information region only, the light pattern produced establishes a different charge pattern when used to expose a charged photoreceptor. The latter charge pattern is developed with…

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