摘要 |
The present invention relates to a film formation composition for improving the blackening of the surface of a steel sheet, particularly, the surface of a steel sheet containing Mg on the surface thereof, such as a Mg sheet, a plated steel sheet having a plated layer comprising Mg, and the like, a steel sheet comprising a film formed by the composition, and a method for forming the film. Provided are a film formation composition for preventing the blackening of the surface of a steel sheet, comprising: 2.5-7.5 parts by weight of a water-soluble phenoxy resin; 0.1-0.5 parts by weight of a fluorometal acid; 0.1-0.5 parts by weight of a metal compound; and 1-5 parts by weight of a cross-linking agent, wherein the steel sheet is a magnesium sheet comprising magnesium on the surface thereof or a steel sheet having a plated layer containing magnesium, a steel sheet comprising a film formed by the composition, and a method for forming the film. |