ALUMINUM MATERIAL HAVING SUPERIOR ETCHING CHARACTERISTIC FOR ELECTROLYTIC CAPACITOR ELECTRODE, MANUFACTURING METHOD THEREFOR, ELECTRODE MATERIAL FOR ALUMINUM ELECTROLYTIC CAPACITOR, AND ALUMINUM ELECTROLYTIC CAPACITOR

摘要

PROBLEM TO BE SOLVED: To provide an aluminum material having superior etching characteristics for an electrolytic capacitor electrode, which can reliably increase the surface area, by making etch pits densely and uniformly formed on its surface, using the etch pits as starting points, and making them further deeply etched into tunnel-shaped pits so as to be hardly combined with each other, and consequently can increase the capacitance. SOLUTION: The aluminum material 1 has an oxide film 3 formed on its surface, and aluminum-matrix-exposed sites 5 having no oxide film 3 present thereon formed in such a dispersed state that the perimeter of the site is surrounded by the oxide film, wherein a ratio of the total area of the aluminum-matrix-exposed sites 5 to the total surface area is 10 to 50%. COPYRIGHT: (C)2007,JPO&INPIT