Patent · US Expired

Developing device using two-component developer

US6023601A · kind A · utility

1Cited by
2References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 10, 1999
Grant dateFeb 8, 2000
Priority date
Expiry dateFeb 10, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G15/0921
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

In a developing device for visualizing an electrostatic latent image using two-component developer containing toner and magnetic carrier, excellent development will be performed and deterioration of the developer will be prevented. A developer carrier opposite to an image carrier having an electrostatic latent image formed thereon is prepared by forming a thin layer of aluminum with a thickness of 3 .mu.m or less on the peripheral surface of a roll-shaped member made of ferrite, and the surface roughness Rz of the peripheral surface of the foregoing ferrite roll is set to 50 .mu.m or less. N-poles and S-poles are alternately magnetized at a 50-to-250-.mu.m pitch along the peripheral surface of this ferrite roll. These magnetic poles can be magnetized to have uniform intensity because the peripheral surface of the roll has been smoothly finished, and a developer layer having only substantially one layer of the carrier uniformly attracted is formed on the peripheral surface. On the other hand, a magnetic recording layer is provided on a roll-shaped conductive substrate, and its surface may be finished so as to satisfy relation of Rz.ltoreq.50 .mu.m. At this time, the thickness of the…

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