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:
Jun. 23, 1987
Filed:
Jun. 01, 1984
Rustum Roy, State College, PA (US);
Dinesh K Agrawal, State College, PA (US);
Ronnen A Roy, State College, PA (US);
The Perkin-Elmer Corporation, Norwalk, CT (US);
Abstract
A low expansion ceramic composition is represented by the formula Ca.sub.0.5 Ti.sub.2 P.sub.3 O.sub.12 in which up to 100 percent of the Ca is replaced by one or more of the other alkaline earth metals and alkali metals, the alkali metals being selected from the group consisting of Na, Li, K and combinations thereof and substituted in the ratio of two units of alkali metal for each unit of Ca replaced. Up to 100 percent of the Ti is replaced by one or more members selected from the group consisting of Zr, Sn, Nb, Ta and Cr. For each unit of Cr replacement an approximately equal unit of alkali metal is added. For each unit of Nb and/or Ta replacement an approximately equal unit of Na and/or K replaces a unit of Ca. Up to 100 percent of the P may be replaced by Si and/or S. The total of the amounts of Ca, other alkaline earth metals, Li, K, Ti, Sn, Nb, Ta and Cr is greater then zero. Preferably up to 100 percent of the Ca is replaced by Na, and up to 100 percent of the Ti is replaced by Zr or NaCr. The ceramic composition is especially suitable for optically reflecting films.