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:
May. 05, 2009
Filed:
Mar. 13, 2008
Nobuhiro Miyakawa, Nagano, JP;
Shinji Yasukawa, Nagano, JP;
Hiroyuki Murakami, Nagano, JP;
Seiko Epson Corporation, Tokyo, JP;
Abstract
The present invention provides a toner having: a toner mother particle; a first external additive including a first inorganic fine particle having a primary particle size distribution of 200 to 750 nm and a work function approximately equivalent to that of the toner mother particle; a second external additive including a second inorganic fine particle having an mean particle size smaller than that of the first inorganic fine particle and a work function smaller than that of the toner particle, a stirring member of a developing device and/or an inner wall of the developing device; and 0.01% to 0.3% by weight of a metal soap having a work function approximately equivalent to that of the toner mother particle.