| abstract |
It is an object of the invention to provide a chemical conversion treating agent which contains no chromium and can give good effect of chemical conversion treatment equal to or better than that of zinc phosphate treatment to all metals such as iron, zinc, aluminum and the like. The present invention provides a chemical conversion treating agent comprising zirconium, fluorine and a water-soluble epoxy compound, wherein the content of the zirconium in the chemical conversion treating agent is 20 to 10000 ppm on the metal equivalent basis, the water-soluble epoxy compound has a fundamental skeleton of bisphenol F, has an amino group and an isocyanate group, has a number-average molecular weight of 400 to 1000, and the content of the water-soluble epoxy compound in the chemical conversion treating agent is 100 to 2000 ppm in terms of the concentration of solid matters. |