| 摘要 |
PROBLEM TO BE SOLVED: To obtain an etching liquid which enables etching of a polyimide resin which is difficult for etching with a conventional etching liquid and to obtain an etching method suitable for various states of resins, especially for etching of a polyimide film. SOLUTION: An etching liquid essentially comprising oxyalkylamine and alkali metal compd., and if necessary, with addition of either or both of urea and org. polar solvent is used. This etching liquid is preferentially used for etching of a polyimide resin which is obtd. by polymn. condensation of biphenyltetracarboxylic acid dianhydride and diaminobenzene and which is considered difficult for etching with a conventional etching liquid. A polyimide film of this resin is preferably dipped in the etching liquid and etched while irradiating ultrasonic waves. |
