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:
Nov. 29, 2011
Filed:
Aug. 31, 2007
Electrographic carrier, developer, developing method, image forming apparatus, and process cartridge
Kimitoshi Yamaguchi, Shizuoka, JP;
Naoki Imahashi, Shizuoka, JP;
Masashi Nagayama, Shizuoka, JP;
Ricoh Company, Ltd., Tokyo, JP;
Abstract
A carrier is provided including a core and a resin layer located overlying the core, wherein the carrier has a weight average particle diameter (Dw) of from 22 to 50 μm, a ratio (Dw/Dp) of the weight average particle diameter (Dw) to a number average particle diameter (Dp) of from 1 to 1.30, a shape factor SF-1 of from 100 to 120, and a shape factor SF-2 of from 100 to 120, and wherein the carrier comprises core particles satisfying the following relationship 0.52<(d/D)<1.0 in an amount of from 0 to 10,000 ppm by number: wherein D (μm) represents a diameter of a circle having the same area as that of a projected image of a core particle and d (μm) represents a diameter of a circle having the same area as that of a projected image of a maximum hollow present in the core particle.