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, 1991
Filed:
Oct. 11, 1989
Toshiba Ceramics Co., Ltd., , JP;
Abstract
Silica powder or a mixture of silica powder and silicon nitride whisker is heated at a temperature ranging from 800.degree. C. to 1,700.degree. C. in a gas mixture of ammonia gas (NH.sub.3) and hydrocarbon gas (C.sub.m H.sub.n) so as to produce silicon nitride whisker. The gas mixture flows at the rate of 10 mm/sec or less. The NH.sub.3 /CH.sub.4 ratio of the ammonia to the hydrocarbon, expressed as CH.sub.4, ranges from 0.5:1 to 2000:1 by volume. The silica powder is preferably mixed with at least one of six catalysts: transition metals; alkali metals; alkaline earth metals; halides of transition metals; halides of alkali metals; and alkaline earth metals. One mol part of the silica powder is mixed with 0.001-1.0 mol part of the catalyst.