The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 11, 2009
Filed:
Sep. 23, 2005
Hisao Okada, Ibaraki, JP;
Hiroyuki Mabuchi, Ibaraki, JP;
Teruaki Mitsuya, Ibaraki, JP;
Tsuneaki Kawanishi, Ibaraki, JP;
Akio Tsujita, Ibaraki, JP;
Hisao Okada, Ibaraki, JP;
Hiroyuki Mabuchi, Ibaraki, JP;
Teruaki Mitsuya, Ibaraki, JP;
Tsuneaki Kawanishi, Ibaraki, JP;
Akio Tsujita, Ibaraki, JP;
Ricoh Company Ltd., Tokyo, JP;
Abstract
An electrophotographic apparatus includes: a photoconductor; and two developing rollers facing the photoconductor. A developer fed out from between the two developing rollers is supplied to the photoconductor by the two developing rollers to form a toner image on the photoconductor. The developer includes a carrier having a volume-average particle size smaller than 70 μm and a volume resistivity not lower than 10Ω·cm. A volume ratio of the carrier in a facing portion between the photoconductor and the developing rollers is not lower than 30% and not higher than 46%.