| 摘要 |
<p>In the production of a printed wiring board by a semi-additive technique, an aqueous solution containing 54 to 180 g/L of sulfuric acid, 16 to 96 g/L of iron (III) sulfate and 0.02 to 0.15 g/L of 5-amino-1H-tetrazole is used as a (sulfuric acid)/(iron (III) sulfate)-type copper etching solution to be used for the etching removal of an electroless copper coat, which serves as a seed layer, subsequent to the formation of a pattern by electrolytic copper plating.</p> |
