Patent · US Expired

Developing method using a two-ingredient type developer and image forming apparatus using the same

US7283774B2 · kind B2 · utility

4Cited by
4References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 21, 2006
Grant dateOct 16, 2007
Priority date
Expiry dateApr 21, 2026

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG03G2215/0609
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A developing method of the present invention is practicable with a developing unit of the type including a rotatable, nonmagnetic sleeve and a rigid metering member. A two ingredient type developer made up of magnetic carrier grains and toner grains is magnetically deposited on the sleeve. The metering member meters the amount of the developer deposited on the sleeve. The sleeve has surface roughness Rz ranging from 5 μm to 20 μm. The carrier grains each are covered with a coating layer containing at least binder resin and grains. The ratio of the diameter D of the individual grain contained in the coating layer to the thickness h of the binder resin layer lies in the range of 1<D/h<10. The carrier grains have a weight-mean grain size ranging from 20 μm to 60 μm.

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