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. 28, 1999
Filed:
Sep. 24, 1998
Takakuni Kobori, Susono, JP;
Tsutomu Onuma, Yokohama, JP;
Nobuyuki Okubo, Yokohama, JP;
Masaichiro Katada, Souka, JP;
Masao Takano, Susono, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A magnetic toner includes magnetic toner particles containing at least a binder resin and a magnetic iron oxide. The magnetic iron oxide contains 0.2 to 4.0% by weight of at least one metal element selected from the group consisting of Mn, Zn, Ni, Cu, Co, Cr, Cd, Al, Sn and Mg, and 0.2 to 0.8% by weight of silicon element on the basis of an iron element; the ratio (B.sub.si /A.sub.Si).times.100 of the content B.sub.Si of the silicon element present in the magnetic iron oxide up to an iron element solubility of 20% by weight to the total content A.sub.Si of the silicon element present in the magnetic iron oxide is 45 to 85%; the ratio (C.sub.si /A.sub.Si).times.100 of the content C.sub.Si of the silicon element present in the magnetic iron oxide up to an iron element solubility of 10% by weight to the total content A.sub.Si is 35 to 70%; and the magnetic toner has a weight average particle diameter of 3.5 to 10.0 .mu.m, and contains 0 to 30% by volume of magnetic toner particles having a volume particle diameter of 12.7 .mu.m or more determined from a volume distribution.