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:
Jun. 01, 2021
Filed:
May. 15, 2020
Canon Kabushiki Kaisha, Tokyo, JP;
Kazunori Hashimoto, Numazu, JP;
Katsuhiro Kojima, Mishima, JP;
Toshiaki Takeuchi, Susono, JP;
Yasukazu Ikami, Tokyo, JP;
Kosuke Ikada, Machida, JP;
Yoshihiro Mitsui, Mishima, JP;
Yuichiro Hirata, Susono, JP;
Go Shindo, Mishima, JP;
Akinobu Saito, Yokohama, JP;
Yuhei Terui, Numazu, JP;
Noriyoshi Umeda, Sunto-gun, JP;
Tomonori Matsunaga, Sunto-gun, JP;
Shohei Kototani, Sunto-gun, JP;
Masamichi Sato, Mishima, JP;
CANON KABUSHI KIKAISHA, Tokyo, JP;
Abstract
A process cartridge includes a seal member contacting an image bearing member upstream in the rotation direction of the image bearing member from a cleaning member and allowing the developer to move from upstream in the rotation direction from the contact part between the seal member and the image bearing to downstream from the contact part while regulating movement from downstream to upstream from the contact part. The developer has surface protrusions containing an organic silicon polymer, wherein either (i) the work function of the seal member is greater than the work function of the developer when the developer has a negative charging polarity and is smaller than the work function of the developer when the developer has a positive charging polarity, or (ii) the absolute value of the difference between the work function of the seal member and the work function of the developer is within a predetermined range.