Patent · US Expired

Image forming apparatus having an alternating bias electric field

US5202731A · kind A · utility

28Cited by
24References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 26, 1992
Grant dateApr 13, 1993
Priority date
Expiry dateAug 26, 2012

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/0907
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An image forming apparatus is formed by providing a latent image-bearing member for holding an electrostatic image thereon and a toner-carrying member for carrying a prescribed magnetic toner comprising a binder resin and magnetic powder and having a particle size distribution including 12% by number or more of magnetic toner particles of 5 microns or smaller, 33% by number or less of magnetic toner particles of 8-12.7 microns and 2% by volume or less of magnetic toner particles of 16 microns or larger so as to provide a volume-average particle size of 4-10 microns. At the developing station, an alternating bias voltage comprising a DC voltage and an unsymmetrical AC voltage in superposition is applied between the toner-carrying member and the latent image-bearing member to provide an alternating bias electric field comprising a development-side voltage component and a reverse-development side voltage component. The development-side voltage component has a magnitude equal to or larger than that of the reverse development-side voltage component and a duration smaller than that of the reverse-development side voltage component, so that the magnetic toner on the toner-carrying member,…

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