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:
Sep. 22, 2009
Filed:
Feb. 21, 2006
Kohei Matsuda, Shizuoka-ken, JP;
Tetsuya Kobayashi, Numazu, JP;
Masato Koyanagi, Mishima, JP;
Shinichi Agata, Shizuoka-ken, JP;
Shinya Yamamoto, Numazu, JP;
Kentarou Kawata, Numazu, JP;
Taku Watanabe, Susono, JP;
Kohei Matsuda, Shizuoka-ken, JP;
Tetsuya Kobayashi, Numazu, JP;
Masato Koyanagi, Mishima, JP;
Shinichi Agata, Shizuoka-ken, JP;
Shinya Yamamoto, Numazu, JP;
Kentarou Kawata, Numazu, JP;
Taku Watanabe, Susono, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A charging device for electrically charging an image bearing member, includes a contact charging member contactable to the image bearing member to charge the image bearing member, the contact charging member being supplied only with a DC voltage; and a contact member contacted to the charging member, wherein the image bearing member is adapted to carry a toner image of toner which contains an externally added material comprising silica, wherein work functions of the charging member, the contact member and the silica satisfy,(the work function of the contact member)>(the work function of the silica)>(the work function of the charging member).