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. 09, 1988
Filed:
Oct. 20, 1986
Applicant:
Inventors:
Assignee:
Sumitomo Chemical Company, Limited, Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C01B / ;
U.S. Cl.
CPC ...
423344 ; 423406 ;
Abstract
A method for producing .alpha.-form silicon nitride having a central particle diameter of 0.3 to 1.0 .mu.m (.alpha.-Si.sub.3 N.sub.4) of high-grade and fine powder for its sintered body excellent in heat-stability and mechanical strength which comprises heat-treating at 1,450.degree.-1,550.degree. C., in an atmosphere containing nitrogen, a mixture prepared by adding one of additives: