| abstract |
A surface treatment solution excellent in stability during storage forming a coating for treatment excellent in waterproofness, solvent resistance, and adhesion with a plated steel sheet and able to provide a surface treated steel sheet with hot-pressing lubricity, chemical convertability after hot-pressing, corrosion resistance after coating, and spot weldability, that is, a surface treatment solution for a plated steel sheet to be hot-pressed comprising a ZnO aqueous dispersion (A) and a water dispersible organic resin (B), wherein the ZnO aqueous dispersion (A) comprises water and ZnO particle size having 50 to 300 nm particles, the water dispersible organic resin (B) has a 5 to 45 mgKOH/g acid value and 5 to 300 nm emulsion particle size, and a mass ratio (W A /W B ) of a mass of ZnO particles in the ZnO aqueous dispersion (W A ) to a mass of solid content of the water dispersible organic resin (W B ) is 30/70 to 95/5. |