abstract |
[Problem] To provide a surface treatment agent for zinc-plated steel sheets, said agent satisfying all of corrosion resistance, adhesiveness with top coat paints, blackening resistance, and adhesiveness with structural adhesives. [Solution] This water-based surface treatment agent for zinc plated steel sheets, said surface treatment agent being obtained by blending a zirconium carbonate compound, a specific acrylic resin, a vanadium compound, a phosphorous compound, and a cobalt compound. |