| 摘要 |
PROBLEM TO BE SOLVED: To improve the corrosion resistance of a screw component for fastening in which a chemical film is formed on galvanizing or galvannealing while maintaining its friction coefficient equal to the level required heretofore.SOLUTION: Provided is a water-soluble coating agent composition for galvanizing or galvannealing, fed to the formation of a coating film to a screw component for fastening and the part having a part in contact with the screw component for fastening upon fastening, comprising a polymer with a prescribed structure, at least one selected from the group consisting of at least one kind of a copolymer of at least one selected from the group consisting of styrene, vinyl, ethylene, α-olefin and maleic acid together with the polymer, and at least one kind of metal oxide, and, when the composition is applied to galvanizing or galvannealing or the surface of a chemical film applied to the platings, the coating film in which the total friction coefficient measured in accordance with JISB 1084 shows 0.25 to 0.45 is formed.SELECTED DRAWING: None |
