| abstract |
Disclosed is a non-chromic rust preventive surface treatment agent which forms a silica-like coating that hardly causes cracks or peeling problems on the zinc surface of a metal member and gives good rust preventive performance. The non-chromic antirust surface treatment agent is an alcohol solution of an alkoxysilane oligomer having a weight average molecular weight of 1,000 to 10,000, wherein 2.5 to 15% of silicon in the alkoxysilane oligomer molecule is substituted with titanium. In order to obtain an alkoxysilane oligomer partially substituted with titanium, a titanium compound chelated about half of the alkoxy group of titanium tetraalkoxide is reacted with a tetraalkoxysilane monomer or alkoxysilane oligomer in an alcohol solution.n n n Non-chromic antirust surface treatment agent, metal member with zinc surface, antirust film, alkoxysilane oligomer |