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. 16, 2014
Filed:
Oct. 15, 2012
Canon Kabushiki Kaisha, Tokyo, JP;
Emi Hagiwara, Yokohama, JP;
Yasunori Chigono, Atsugi, JP;
Hirokazu Usami, Kawasaki, JP;
Manami Haraguchi, Yokohama, JP;
Ryo Inoue, Kawasaki, JP;
Shintaro Ishida, Toda, JP;
Tomoaki Miyazawa, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A toner containing toner base particles and an external additive, wherein regions with different tribocharging polarities with respect to a magnetic carrier are present in a domain-matrix structure on the surface of the toner base particles. The island region B has a predetermined height, the external additive has a reverse polarity to the region B in terms of tribocharging polarity to the magnetic carrier, the external additive contains a first external additive having a number-average primary particle size of 80-150 nm and a second external additive having a number-average primary particle size of 10-60 nm, and an average coverage Cb (%) with the first external additive in the region B is 27-100% and a coverage Ca (%) with the first external additive in the sea region A is 12% or less.