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. 19, 2008
Filed:
Dec. 13, 2002
Hideki Sugiura, Fuji, JP;
Satoshi Mochizuki, Numazu, JP;
Yasuaki Iwamoto, Numazu, JP;
Kazuhiko Umemura, Shizuoka, JP;
Hideki Sugiura, Fuji, JP;
Satoshi Mochizuki, Numazu, JP;
Yasuaki Iwamoto, Numazu, JP;
Kazuhiko Umemura, Shizuoka, JP;
RICOH Company, Ltd., Tokyo, JP;
Abstract
An external additives for electrophtographic toner comprising finely divided oxide particulate including a silicon compound and a compound for doping said oxide particulate, wherein particle diameter of the primary particle of said finely divided oxide particulate is in the range of 30 nm to 150 nm, and the primary particle of said finely divided oxide particles is substantially spherical shape having the roundness in the range of 0.95 to 0.996, is provided. And this external additives is capable of evading from the embedding of external additives into toner even if after the toner is held in the storage under the condition of high temperature and high humidity, thereby the additives is capable of showing sufficient functions as fluidizing agent and charge supplement agent, and is capable of inhibiting an abnormal charge elevation even after being stored under the low temperature and low humidity.