公开(公告)号：US11174556B2

公开(公告)日：2021-11-16

申请号：US16340134

申请日：2017-10-06

Applicant: JFE STEEL CORPORATION

Inventor： Reona Endo ,  Kazuhisa Okai ,  Hiroshi Kajiyama ,  Takashi Kawano

IPC: C23C22/60 ,  C23C22/82 ,  C23C26/00 ,  C23C22/00 ,  C23C2/26 ,  C23C2/06 ,  C23C28/00 ,  C23C22/78

Abstract: Disclosed is a surface-treatment solution for producing a zinc or zinc alloy coated steel sheet with a surface-coating layer that does not contain a chromium compound in the surface-coating layer and that is excellent in all of heat discoloration resistance, heat cracking resistance, planar part anti-corrosion property, corrosion resistance after alkali degreasing, blackening resistance, stack blackening resistance, anti-water stain property, solvent resistance, perspiration resistance, coating adhesion property, and storage stability. The disclosed surface-treatment solution contains a glycidyl group-containing silane coupling agent (A), a tetraalkoxysilane (B), a zirconium carbonate compound (C), and an anionic polyurethane resin (D) having a glass transition temperature (Tg) of 80° C. to 130° C., a vanadium compound (E), a molybdic acid compound (F), and water, the surface-treatment solution having a pH of 8.0 to 10.0, and the amount of each component satisfying a predetermined relationship.