METHOD FOR HARDENING RESIST FILM

摘要

PROBLEM TO BE SOLVED: To prevent uneven hardening of a resist film contg. casein and a dichromate and to keep fine holes formed in large numbers in the surface of the film uniform in diameter by specifying the concn. of chromic anhydride in a hardening soln. for hardening the resist film. SOLUTION: A hardening soln. contg. 0.2-0.4% chromic anhydride is fed to a metallic sheet with a resist film contg. casein and a dichromate and having a prescribed pattern formed on the principal surface to harden the resist film. When the resist film contains PVA and a dichromate, the concn. of chromic anhydride in the hardening soln. is regulated to 0.8 to <1.0%. Whether the pattern is a high definition pattern or not, a high quality resist film is obtd. The amt. of the dichromate used is reduced and load on the environment is reduced.