| 摘要 |
PURPOSE:To prolong the service life of a chemical copper plating soln. by adding an ionic surfactant to the plating soln. so as to prevent the deterioration of the plating soln. due to the accumulation of alkali metallic salts during repeated use. CONSTITUTION:A cationic surfactant such as cetyltrimethylammonium chloride or dodecylpyridinium chloride is added to a chemical copper plating soln. contg. bivalent copper ions such as copper sulfate as a base, a complexing agent for bivalent copper ions, a reducing agent for bivalent copper ions, a pH adjusting agent, a complexing agent for univalent copper ions and a polyoxyethylene type nonionic surfactant as essential components. The amount of the cationic surfactant added is 50mg per 1l plating soln. Even when the resulting plating soln. is repeatedly used, the coagulation of the nonionic surfactant due to the accumulation of the Na salts of sulfuric acid and formic acid is inhibited, preventing the deterioration of the performance of the plating soln., and shortering of the service life of the plating soln. |
