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:
Jan. 01, 2013
Filed:
Mar. 26, 2008
Tomoya Yamada, Okayama, JP;
Isao Fujita, Okayama, JP;
Yoshiaki Aiki, Okayama, JP;
Dowa Electronics Materials Co., Ltd., Tokyo, JP;
Dowa IP Creation Co., Ltd., Okayama, JP;
Abstract
To provide a carrier for two-component electrophotographic developer not only having excellent fluidity but also having proper surface irregularities necessary for imparting electric charge, without generating cracks/chipping of particles even under an influence of stirring stress over a long period of time. A particle surface has raised parts of striped pattern extending almost continuously in a plurality of directions while being superposed on one another, with a surface formed with raised parts of striped pattern occupying 80% or more of the whole surface of a particle. Depths of grooves between the adjacent raised parts are 0.05 μm or more and 0.2 μm or less, average surface roughness Ra is 0.1 μm or more and 0.3 μm or less, roundness is 0.90 or more, and average particle size is 15 μm or more and 100 μm or less, and a carrier core material thus constituted is coated with resin. Thus, the carrier for two-component electrophotographic developer is prepared.