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:
Dec. 12, 2000
Filed:
Aug. 13, 1999
Yoshinobu Baba, Yokohama, JP;
Yuzo Tokunaga, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A two-component type developer for developing an electrostatic image is constituted by at least a toner and a magnetic carrier. The toner has a weight-average particle size D4 of at most 10 .mu.m and a number-average particle size D1 satisfying D4/D1.ltoreq.1.5. The magnetic carrier comprises composite particles comprising magnetic iron compound particles, non-magnetic metal oxide particles, and a binder comprising a phenolic resin. The composite particles contain the magnetic iron compound and the non-magnetic metal oxide in a total proportion of 80-99 wt. %. The magnetic iron compound particles have a number-average particle size ra, and the non-magnetic metal oxide particles have a number-average particle size r.sub.b satisfying r.sub.b /r.sub.a >1.0.