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. 31, 2021
Filed:
Feb. 03, 2021
Sumitomo Riko Company Limited, Aichi, JP;
Yoshihiro Saito, Aichi, JP;
Hiroshi Ukai, Aichi, JP;
Sumitomo Riko Company Limited, Aichi, JP;
Abstract
In a charging roll for electrophotographic equipment, an outer surface layer of an elastic layer includes a binder resin, large-diameter particles having an average particle diameter of 15-50 μm, and small-diameter particles having an average particle diameter of 3-15 μm, a difference in average particle diameter between the large-diameter particles and the small-diameter particles is 10-35 μm, the small-diameter particles are arranged in one layer in the surface layer, the average distance between the small-diameter particles is not more than 1.2 times the average particle diameter of the small-diameter particles, the thickness a of the binder resin covering the large-diameter particles is within the range of 1.5-3.5 μm, the thickness b of the binder resin covering the small-diameter particles is 3.0-6.0 μm, and the thickness b is larger than the thickness a.