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:
Feb. 28, 2012
Filed:
Dec. 04, 2007
Jun Mizuno, Shizuoka, JP;
Toshihiro Matsuba, Tokyo, JP;
Shigeo Yamamoto, Shizuoka, JP;
Takashi Yamada, Shizuoka, JP;
Jun Mizuno, Shizuoka, JP;
Toshihiro Matsuba, Tokyo, JP;
Shigeo Yamamoto, Shizuoka, JP;
Takashi Yamada, Shizuoka, JP;
Nippon Light Metal Company, Ltd., Tokyo, JP;
Abstract
Provided is a process for producing a high-purity α-alumina in which an Si content, an Fe content, a Ca content, and an Na content are simultaneously removed. The high-purity α-alumina is produced by burning aluminum hydroxide having an Na content of 0.11 mass % or less, an Fe content of 6 ppm or less, a Ca content of 1.5 ppm or less, and an Si content of 10 ppm or less as impurities in terms of alumina respectively, and having an average particle diameter of 55 μm or less at a burning temperature of 1,100 to 1,500° C. by using a burning vessel containing AlOin a range of 85 to 93 wt % and SiOin a range of 7 to 14 wt % and subjecting the obtained α-alumina to wash treatment.