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. 18, 1994
Filed:
Mar. 25, 1993
Applicant:
Inventors:
Assignee:
Nissan Chemical Industries, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C04B / ;
U.S. Cl.
CPC ...
501103 ; 501104 ;
Abstract
A zirconia ceramic composed of crystals which scarcely undergo phase transformation from tetragonal system to monoclinic in the temperature range of from 100.degree. C. to 300.degree. C. even in the presence of water vapor or water is disclosed, said zirconia ceramic comprising at least 93% by weight of partially stabilized zirconia mainly composed of tetragonal crystals and containing mainly Y.sub.2 O.sub.3 and ZrO.sub.2 at the former to the latter molar ratio of from 2/98 to 4.5/95.5 and balance of at least one of the oxides selected from the group consisting of boron oxide, germanium oxide, and gallium oxide, wherein the content of the boron oxide is 1% by weight or less.