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:
Aug. 04, 1992
Filed:
Jan. 18, 1991
Satoshi Matsunaga, Tokyo, JP;
Takashige Kasuya, Tokyo, JP;
Hiroaki Kawakami, Kawasaki, JP;
Kiyoko Tsuchiya, Yokohama, JP;
Yusuke Karami, Yokohama, JP;
Shinji Doi, Kawasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A toner for developing an electrostatic image, comprises a binder resin and a colorant. Such binder resin contains a THF-insoluble matter in an amount of less than 10 wt. % based on the binder resin, and, in the molecular weight distribution measured by GPC (gel permeation chromatography) of a THF-soluble matter, has a weight average molecular weight/number average molecular weight (Mw/Mn) of .gtoreq.18, a molecular weight peak MA in the region of a molecular weight of from 3,000 to 20,000, a molecular weight peak MB in the region of a molecular weight of from 380,000 to 1,000,000, a molecular weight minimum Md in the region of a molecular weight of from 20,000 to 380,000, provided that MB/MA is in the range of from 30 to 150, and a molecular weight distribution curve area ratio SA:SB:Sd of 1:0.3 to 0.8:0.35 to 0.8.