Patent ID: 7400491

Claim:
An aluminum electrolytic capacitor comprising: a capacitor element prepared by rolling an anode foil and a cathode foil together with a separator, said capacitor element being impregnated with a driving electrolyte; an anode lead connected to said anode foil; a cathode lead connected to said cathode foil; a tubular metal case having one closed end and the other open end, and containing said capacitor element; and a sealing member hermetically closing said open end, wherein said anode and cathode leads are bent along an outer surface of said sealing member, wherein said sealing member is comprised of a rubber composition containing: a rubber component having, as a primary constituent, a butyl rubber prepared by crosslinking an isobutylene-isoprene copolymer having an unsaturation degree of 1.2 to 2.5 mol %, with an alkyl-phenol-formaldehyde resin; and 100 to 200 mass parts of reinforcing filler with respect to 100 mass parts of said rubber component, said rubber composition having a Wallace hardness according to International Rubber Hardness Degree (IRHD) of 80 Hw or more, and a tensile elastic modulus at a solder reflow temperature of 4 N/mm 2 or more.