| abstract |
The present invention relates to a non-chromium metal surface treatment agent having excellent anti-corrosion performance that can be used for the surface treatment of metal products with rust-preventive coatings, especially galvanized products. The metal surface treatment agent consists of a silica-based binder solution in which water and / or alcohol is a medium, and the silica component concentration contained in the silica-based binder solution is 8 to 25% by weight. In particular, a metal surface treatment agent mainly containing an alcohol solution of an alkoxysilane oligomer having a weight average molecular weight of 1,000 to 10,000 in which the silica binder solution is hydrolyzed and condensed with the alkoxysilane can suppress the generation of white blue. It is preferable to suspend 3 to 25 parts by weight of the ultrafine titanium oxide powder having an average particle diameter of 70 nm or less of the primary particles dispersed in the silica binder solution based on 100 parts by weight of the silica component. By using polyvinyl butyral resin soluble in alcohol together with a metal surface treatment agent and adding a silane coupling agent having a vinyl group or an epoxy group as a functional group, a dispersion-treated titanium oxide ultrafine powder, and the like, the antirust performance can be further improved. have. n n n Non-chrome metal surface treatment agent, antirust coating, antirust performance, silica binder solution, alkoxysilane, titanium oxide. |