US Patent 11920059 Coating material

A coating material is allowed to contain a sulfate having a higher degree of solubility in water than that of calcium sulfate. The sulfate is an additive for coating materials which is used for reducing the consumption of zinc (including zinc oxide) in a coating film formed from the coating material and the corrosion of a base material when the coating film is scratched. The content of the sulfate can be 0.004 to 0.65 mol per 100 g of the content of zinc. Alternatively, the content of the sulfate may be 0.006 to 0.186 mol per 100 g of a heating residue (except for the sulfate added) of a coating film.