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:
Sep. 10, 2002
Filed:
May. 30, 2000
Masanori Ito, Numazu, JP;
Tsutomu Kukimoto, Yokohama, JP;
Tsuyoshi Takiguchi, Shizuoka-ken, JP;
Tatsuhiko Chiba, Kamakura, JP;
Michihisa Magome, Shizuoka-ken, JP;
Akira Hashimoto, Mishima, JP;
Keiji Komoto, Numazu, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A toner is formed of toner particles each comprising a binder resin and iron oxide particles dispersed therein. The toner particles are characterized by uniform but non-surface-exposed dispersion of the iron oxide particles within the toner particles as represented by (i) a carbon content (A) and an iron content (B) giving a ratio B/A<0.001 at surfaces of the toner particles as measured by X-ray photoelectron spectroscopy, (ii) an average circularity of at least 0.970, and (iii) at least 50% by number of toner particles satisfying D/C≦0.02, wherein C denotes a projection area-equivalent circular diameter of each toner particle and D denotes a minimum distance of iron oxide particles from a surface of the toner particle, based on a sectional view of the toner particle as observed through a transmission electron microscope (TEM).