| 摘要 |
<p>A copper-zinc alloy electroplating bath which can form a copper-zinc alloy plating layer having improved corrosion resistance and which can form a uniform and bright copper-zinc alloy plating layer having an objective composition over a wide current density range. A copper-zinc alloy plating bath containing a copper salt, a zinc salt, and pyrophosphate ions, wherein the (P/M) ratio is 2.0 to 3.2 [where M represents the total molarity (mol/L) of copper ions and zinc ions in the bath ; and P represents the molarity (mol/L) of additive pyrophosphate ions therein]. The total molarity M (mol/L) is preferably 0.03 to 0.50 (mol/L) and the pH is preferably 5 to 10.</p> |
