Patent · US Expired

Method for producing a large number of copies by means of copying apparatus

US4220699A · kind A · utility

20Cited by
6References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 17, 1978
Grant dateSep 2, 1980
Priority date
Expiry dateMay 17, 1998

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S101/37
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A method whereby a large number of copies can be produced from a single electrostatic latent image formed on one of a dielectric member, an insulating member or photoconductive member by developing and printing the image by transfer printing in successive operations. The absolute value of a bias voltage impressed on the developing device in developing the electrostatic latent image is gradually reduced until the number of copies produced reaches a specific level, and then progressively increased as the number of copies produced increases for producing copies in numbers which exceed the specific level, whereby copies of a number greater than the number of the specific level can be produced from the same electrostatic latent image.

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