ALUMINUM ALLOY SOFT FOIL FOR CATHODE OF ELECTROLYTIC CAPACITOR, AND PRODUCTION METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To provide an aluminum alloy soft foil for the cathode of an electrolytic capacitor which can securely obtain high capacitance and high strength after etching, and to provide a production method therefor. SOLUTION: The aluminum alloy soft foil for the cathode of the electrolytic capacitor has an aluminum purity >=99.0 to <=99.8 mass%, and has a copper content >=0.1 to <=0.6 mass%. The ratio of the precipitation amount of copper to the copper content is <50%. In the method for producing the aluminum alloy soft foil for the cathode of an electrolytic capacitor, in the temperature dropping stage after final annealing, cooling is performed in the temperature range of 250 to 150 deg.C at the average cooling rate of 50 to 100 deg.C/hr.