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:
Jan. 15, 2013
Filed:
Oct. 31, 2006
Osamu Kunitomo, Fukuoka, JP;
Takaaki Tanaka, Fukuoka, JP;
Osamu Kunitomo, Fukuoka, JP;
Takaaki Tanaka, Fukuoka, JP;
Denki Kagaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
Herein disclosed is alumina powder incorporated into a composition which should have excellent heat conduction and used as a heat-radiating member and for sealing a semiconductor. The spherical α-alumina powder has an average sphericity of not less than 0.93 and a content of α-crystalline form is not less than 95% and the spherical α-alumina powder is prepared according to the method, which comprises the steps of: (1) softening metallic aluminum powder or alumina powder through the treatment with a flame; (2) solidifying the softened powder by passing the same through a zone maintained at a temperature ranging from 800 to 500° C.; (3) increasing the content of α-phase by passing the solidified powder through a zone maintained at a temperature ranging from 950 to 1,500° C.; and (4) collecting the resulting powdery product while cooling the same.