Patent · US Expired

Electrophotographic image-forming process using grey toner

US5077158A · kind A · utility

16Cited by
2References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 27, 1990
Grant dateDec 31, 1991
Priority date
Expiry dateApr 27, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G13/09
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In forming an image by developing an electrostatic latent image with a grey toner, a mixture of a white toner and a black toner is used as the grey toner and the ratio (D) of the black toner to the entire toner, the developing voltage (DV) and the image density (ID) are set so that the requirement represented by the following formula is satisfied: EQU ID=A.sub.2 .times.(1-e.sup.-K 2.sup.D).times.(1-e.sup.-K 3.sup.DV) wherein A.sub.2 is a number of from 0.5 to 2.5, K.sub.2 is a number of from 1 to 2, and K.sub.3 is a number of from 0.001 to 0.01. According to this process, a copy having a grey image area corresponding precisely to the image of an original is obtained.

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