| 摘要 |
PROBLEM TO BE SOLVED: To accurately and rapidly etch the resin layer of polyamide without using any amine. SOLUTION: This etching liquid contains 3 wt.%-65 wt.% of diol having 3-6 carbons and triol having 4-6 carbons, 10 wt.%-55 wt.% alkaline compound, and water that is 0.75 to 3.0 times larger than the alkaline compound. By setting this kind of etching liquid to 65 deg.C or higher and etching the resin layer 42 of polyamide whose imidation rate is 50%-98%, the resin layer 42 is etched rapidly, and the working environment is poorly affected. Also, even if the resin layer 42 is completely turned into imidation after etching, the etching pattern of the obtained resin layer 42 is not distorted, and the degree of contamination of the impurity ion of the resin layer 43 becomes smaller than that in a case using conventional etching liquid. |
