Hexavalent-chrome-free process for sealing of a sulfuric acid anodized aluminium alloy, sealing solution therefor and article therefrom

摘要

A sealing method comprises providing a buffered sealing solution comprising a simple cobalt II salt(s) and a simple lithium III salt(s); and bringing a metal substrate (10) having a previously anodized surface into contact with the sealing solution for a period sufficient to form a mixed cobalt/lithium oxide film. An independent claim is also included for a coated article produced using a sealing composition comprising simple cobalt II salt(s), simple lithium III salt(s), and being buffered by which a mixed cobalt/lithium film is obtained.