SEALING OF ANODIZED METALLIC SURFACES IN ORDER TO IMPROVE THE WEATHERING BEHAVIOUR THEREOF

摘要

The invention relates to an aqueous solution for sealing anodized metallic surfaces having a pH value of between 5.5 and 8.5, and containing a) a total of between 0.4 and 50 mg/l of at least one cationic, anionic or non-ionic surfactant, and b) between 0.5 and 500 mg/l of a copolymer of 1) acrylic acid or methacrylic acid or the esters thereof with alcohols having between 1 and 3 C atoms, and 2) hypophosphite salts. The solution is characterised in that it also contains a total of between 0.1 and 100 mg/l of at least one of the following substances: c1) polymers or copolymers based on maleic acid or maleic anhydride, c2) phosphinocarboxylic acid copolymers, and c3) non-polymer organic phosphonic acids. The sealing caused by said solution improves the weathering behaviour of the anodized metallic surfaces.