Patent · US Expired

Reverse development method

US4912003A · kind A · utility

3Cited by
5References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 23, 1988
Grant dateMar 27, 1990
Priority date
Expiry dateAug 23, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/104
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A reverse development method comprising the steps of forming electrostatic image on the surface of an image-bearing member; supplying a developer comprising chargeable magnetic toner based on magnetic powder and a resin development roll comprising a conductive core, a permanent magnet arranged around the conductive core and a dielectric layer provided around and fixed to the permanent magnet and having conductive particles mutually insulated from each other; conveying the developer onto a surface of the image-bearing member by rotation of the developement roll so that the magnetic toner is attracted to the uncharged portions of the image; characterized in that the chargeable magnetic toner contains an aliphatic acid metal salt and is coated with hydrophobic silica.

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