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:
May. 12, 1981
Filed:
Dec. 14, 1979
Matthew M Guzowski, Wallingford, CT (US);
Stephen P Schaffer, Bloomfield, CT (US);
David C Wright, Enfield, CT (US);
The J. M. Ney Company, Bloomfield, CT (US);
Abstract
A tarnish-resistant gold color alloy comprises 30-50 percent by weight gold; 20-50 percent copper; 5-15 percent silver; 2-20 percent zinc; 1.5-15 percent palladium; up to 4.0 percent by weight platinum; and up to 1.0 percent by weight rhenium. The atomic ratio of copper to silver, copper to zinc and copper to palladium are respectively, 6-8:1; 2-12:1; and 5-30:1 and the weight ratios are respectively, 3.5-4.7:1; 3.0-18:1; and 1.95-11.66:1. Dental restorations comprising castings of the alloy have color values on the Hunter scale of L=80-90; a=2.5-3.5; and b=14-18. The dental restorations exhibit tarnish-resistant values of DE.sub.1 less than 13 and DE.sub.10 less than 20.