ALUMINUM FOIL FOR ELECTROLYTIC CAPACITOR AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide aluminum foil for an electrolytic capacitor for middle to high voltages having high capacitance, and a method for manufacturing the aluminum foil. SOLUTION: In this aluminum foil for the electrolytic capacitor, when measurement is made from the surface of the aluminum foil, the average value of depth to an oxygen concentration of 15 atomic % is 100 to 300Å, and the depth is within 1/3 to 3 times larger than the average value. For this method of the aluminum foil for the electrolytic capacitor, in a process for hot-rolling an aluminum ingot, the layer of roll coating is formed on a work roll, and is moved to a finishing hot-rolling plate surface for setting the thickness of the roll coating on the hot-rolling plate surface to 0.1 to 5μm, rolling is made to the final thickness of the aluminum foil by cold rolling, and the aluminum foil is annealed finally.