| 摘要 |
PROBLEM TO BE SOLVED: To provide a treating agent for zinc immersion coating capable of getting a precise zinc immersion film as a pre-treatment of aluminum or aluminum alloy plating, and forming a plating film having a good appearance and a sufficient adhesion strength. SOLUTION: This treating agent for zinc immersion coating contains a zinc compound, alkali hydroxide, iron salt and gluconic acid as a chelating agent for complexing an iron ion. By means of using this treating agent for the first zinc immersion coating in the pre-treatment of aluminum or aluminum alloy plating by the double zincate method, a heterogeneous nucleus generation and growth of zinc on the aluminum oxide film with a relative thickness are achieved without generating of pitting corrosion.
|
