公开(公告)号：US20230399750A1

公开(公告)日：2023-12-14

申请号：US18036316

申请日：2021-11-11

Applicant: NIPPON STEEL CORPORATION

Inventor： Hiromasa SHOJI ,  Kohei UEDA ,  Satoru YONETANI ,  Tomokazu SUGITANI ,  Nobuki SHIRAGAKI

IPC: C23C22/36 ,  C23C30/00

CPC classification number: C23C22/361 ,  C23C30/00

Abstract: A surface-treated metal sheet includes a steel sheet, a coating layer containing zinc formed on the steel sheet and a conversion coating formed on the coating layer, wherein the conversion coating contains an organosilicon compound, a phosphate compound and a fluorine compound, and when the surface roughness in a rectangular area with a side of 1 μm on the surface of the conversion coating is represented by an arithmetic mean height of the scale limited surface Sa, a maximum height of the scale limited surface Sz, and a root mean square height of the scale limited surface Sq, one or more conditions of an arithmetic mean height of the scale limited surface Sa being 0.1 to 10 nm, a maximum height of the scale limited surface Sz being 1 to 1,000 nm, and a root mean square height of the scale limited surface Sq being 0.1 to 100 nm are satisfied.