AQUEOUS SURFACE TREATMENT AGENT FOR METAL

摘要

Provided is an aqueous surface treatment agent for metals that contains a predetermined quantity of: a binder component comprising a mixture, or hydrolytic condensate of said mixture, of 30-70 parts by mass of a tetraalkoxysilane or a low condensate thereof, 70-30 parts by mass of a silica coupling agent containing an epoxy group or an amino group, and 0-40 parts by mass of a mono/di/trialkoxysilane or a low condensate thereof; a phosphate compound; a vanadium compound; and a zirconium compound or a titanium compound. The surface treatment agent for metals forms a chromate-free surface treatment film exhibiting superior coating properties and storage stability, as well as corrosion resistance, adhesion and electrical conductivity.