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:
Jun. 30, 1998
Filed:
Nov. 15, 1996
Tadashi Doujo, Kawasaki, JP;
Yuichi Mizoo, Toride, JP;
Takaaki Kotaki, Yokohama, JP;
Yushi Mikuriya, Kawasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A toner for developing an electrostatic image has a binder resin, a colorant and a charge control agent. The binder resin has a polyester resin having an acid value of from 15 to 40 and a hydroxyl value of 45 or less. The toner has, in its molecular weight distribution as measured by gel permeation chromatography, tetrahydrofuran-soluble matter having a weight average molecular weight Mw of 100,000 or more, having a ratio of weight average molecular weight Mw to number average molecular weight Mn, Mw/Mn, of not less than 35, containing from 70% to 94% of a low-molecular weight region component having a molecular weight of less than 150,000, containing from 1% to 10% of a medium-molecular weight region component having a molecular weight of from 150,000 to 500,000, and containing from 5% to 25% of a high-molecular weight region component having a molecular weight of more than 500,000. The high-molecular weight region component is more than the medium-molecular weight region component.