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:
Apr. 07, 1992
Filed:
Oct. 16, 1989
Larry F Wieserman, Apollo, PA (US);
Karl Wefers, Apollo, PA (US);
Gary A Nitowski, Natrona, PA (US);
Aluminum Company of America, Pittsburgh, PA (US);
Abstract
A process is disclosed for treating the surface of a valve metal such as aluminum to form a two layer protective coating thereon using an anodizing bath consisting essentially of an aqueous solution having a concentration ranging from about 0.001 molar to a saturated solution of a phosphorus-containing compound selected from the class consisting of a phosphorus acid ester and salts thereof. A non-porous barrier valve metal oxide layer is formed on a surface of the valve metal, and a functionalized layer comprised of a phosphate ester is formed on the oxide layer. The functionalized layer protects the oxide layer against chemical attack by the electrolyte during anodizing