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. 16, 1994
Filed:
Nov. 26, 1991
Kiyoko Tsuchiya, Yokosuka, JP;
Koichi Tomiyama, Kawasaki, JP;
Masayoshi Kato, Iruma, JP;
Tsutomu Kukimoto, Yokohama, JP;
Hiroshi Yusa, Yokohama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A toner for developing an electrostatic image is provided as a pulverized mixture including a binder resin and a colorant. The binder resin is characterized by a molecular weight distribution on a GPC chromatogram of its tetrahydrofuran (THF)-soluble resin content including at least 15% and below 35% of a resin component in a molecular weight region of at most 5000 and at least 3 wt. % of a resin component in a molecular weight region of at least 5.times.10.sup.6 and showing a main peak in a molecular weight region of 5000 to 10.sup.5. The binder resin also has an acid value of 2-100 mg KOH/g. The THF-soluble resin component in the molecular weight region of at least 5.times.10.sup.6 is enriched during a melt-kneading step during the toner production.