| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing aluminum foil used for obtaining electrolytic capacitor cathode foil with high capacitance. SOLUTION: An ingot having >=99.7% aluminum purity is prepd. This ingot is subjected to homogenizing treatment under the temp. condition of 500 to 560 deg.C for >=3 hr. After that, hot rolling and cold rolling are executed to obtain aluminum foil having 62.5 to 63.5% IACS electric conductivity. Moreover, the ingot is subjected to homogenizing treatment under the temp. condition of >560 deg.C for >=3 hr. After that, it is subjected to hot rolling to form into an aluminum sheet having 0.3 to 8 mm thickness. This aluminum sheet is subjected to process annealing under the temp. condition of 250 to 450 deg.C for >=1 min. Thereafter, it is subjected to cold rolling to obtain aluminum foil having 62.5 to 63.5% IACS electric conductivity. At the time of subjecting the two types of aluminum foil to etching treatment, electrolytic capacitor cathode foil with high capacitance can be obtd. in either case. |
