| 摘要 |
A zinc-cobalt alloy-plating alkaline bath comprises a zinc compound, a cobalt compound, an alkali hydroxide and a reaction product of an alkyleneamine with an alkylene oxide, the bath having a pH of not less than 13. A method for forming a zinc-cobalt alloy plating film comprises the step of forming, on a substrate, a zinc-cobalt alloy plating film having a cobalt content ranging from 0.05 to 20% by weight and a zinc content ranging from 80 to 99.95% by weight, while using the foregoing alkaline plating bath. The Zn-Co alloy-plating bath permits the achievement of a desired rate of Co-eutectoid even when a small amount of a chelating agent is incorporated into the bath and therefore, the bath is excellent in the disposability of waste water. |
