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:
Jul. 18, 1978
Filed:
Sep. 01, 1976
Bruce Burk, Windsor, CT (US);
Arthur P Burnett, Milford, DE (US);
The J. M. Ney Company, Bloomfield, CT (US);
Abstract
A ceramic raw material essentially contains a pre-formed leucite filler which is obtained by reacting alumina, silica and potassium carbonate and/or oxide at a temperature of at least 1149.degree. C, and nepheline syenite. A leucite-nepheline syenite ceramic raw material which is useful as a dental porcelain powder contains 14 percent by weight of sodium-, potassium-, and lithium carbonates and 86 percent by weight of a 5 percent leucite/95 percent nepheline syenite mixture. Upon fusing of the ceramic raw material of the invention, ceramic bodies are formed which have a crystalline leucite phase dispersed in a matrix of a glassy nepheline phase and any other constituents of the ceramic. The leucite provides the ceramic bodies with desirable properties of controlled thermal expansion and high strength.