摘要 |
<p>A surface-treatment composition for metal sheets, comprising a urethane resin with introduced acid amide groups, having a ratio of urethane bonds to acid amide bonds in the range from 9:1 to 1:9, optionally including chromium or metal compounds selected from the group consisting of Al, Mg, Ca, Zn, Ni, Co, Fe, Zr, Ti, V, W, Mn, and Ce compounds and a silicon compound.</p> |