Patent · US Expired

Transfer apparatus and image bearing apparatus using same having transfer means for contacting a backside of a transfer material

US5010370A · kind A · utility

29Cited by
10References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 24, 1989
Grant dateApr 23, 1991
Priority date
Expiry dateOct 24, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/1675
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An image transfer apparatus for transferring a toner image onto a transfer material includes an image bearing member for carrying a developed toner image; image transfer bias applying roller for contacting to a backside of the transfer material, for urging it to the image bearing member having the toner image and for applying a transfer bias to transfer the toner image to the transfer material; wherein amounts of charge applied to the transfer material by the transfer bias applying roller during its transfer operation satisfy EQU A.gtoreq.B/2 where A (Coulomb/cm.sup.2) is an amount of the charge at a portion where a surface potential of the image bearing member is relatively low, and B (Coulomb/cm.sup.2) is an amount of the charge at a portion where the surface potential of the image bearing member is relatively high. Then, disturbance to the image by the image transfer operation can be avoided.

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