Patent · US Expired

Carrier for electrophotographic developer

US6743558B2 · kind B2 · utility

20Cited by
15References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 1, 2002
Grant dateJun 1, 2004
Priority date
Expiry dateJul 27, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G9/108
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A carrier for electrophotographic developer essentially consisting of a core material of magnetic particles and thereon provided a resinous coating layer, wherein a weight-average particle-diameter(Dw) of the carrier ranges from 25 to 45 &mgr;m, the content of particles having diameter less than 44 &mgr;m is more than or equal to 75% by weight, the content of particles having diameter more than or equal to 62 &mgr;m is less than one percent by weight, the content of particles having diameter less than 22 &mgr;m is less than or equal to 7.0% by weight, the magnetic moment of the carrier at 1 kilo Oe of magnetic field is more than or equal to 76 emu/g. The carrier shows high optical density of image with no smearing of background area, good reproducibility in developing of small dots in image with no carrier deposition.

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