Matsushita Electric Industrial Co., Ltd.

Koichiro Minato

Hiroshi Kurimoto

Junji Yamane

Yuichiro Tsubaki

Hiroyuki Matsuura

Yoshihiro Watanabe

Yukihiro Nitta

Munehiro Morokuma

Disclosed is an aluminum electrolytic capacitor, which comprises a capacitor element prepared by rolling an anode foil and a cathode foil together with a separator and impregnating them with a driving electrolyte, an anode lead electrically connected to the anode foil, a cathode lead electrically connected to the cathode foil, a tubular metal case having one closed end and the other open end and containing the capacitor element, and a sealing member hermetically closing the open end, wherein the anode and cathode leads are bent along an outer surface of the sealing member. In this aluminum electrolytic capacitor, the sealing member is comprised of a rubber composition containing a rubber component having, as a 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 the rubber component. The rubber composition has 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/mmor more.

Aluminum electrolytic capacitor and method of producing the same

The electronic component of the present invention includes a case having an opening, an electronic component element and electrolytic solution disposed in the case, and a sealing member disposed so as to seal the opening. The sealing member has elasticity and is formed of a cross-linked structure of compound. The compound contains butyl rubber polymer as main component, phenol-based additive, and silane-based additive. Accordingly, the sealing member is improved in air-tightness, and the volatilization of the electrolytic solution becomes lessened. Further, an electronic component having such sealing member ensures excellent mounting ability. As a result, it is possible to obtain an electronic component capable of assuring excellent reliability for a long period of time even in a high temperature atmosphere and under high-temperature high humidity conditions.

Electronic component

The present invention provides a highly reliable aluminum electrolytic capacitor which has no flash point and shows little change or degradation in external appearance and properties. The water content of electrolytic solution of the electrolytic capacitor of this invention is 20-90 wt % and one or more following compounds are included as main electrolytes in the electrolytic solution; ammonium formate, ammonium acetate, ammonium lactate, ammonium glycolate, ammonium oxalate, ammonium succinate, ammonium malonate, ammonium adipate, ammonium benzoate, ammonium glutarate, and ammonium azelate. The electrolytic solution also contains not less than 1 wt % of one or more compounds selected from organic carboxylic acids with a particular structure and ammonium salts of these organic acids. The melting point of the electrolytic solution is &minus;10&deg; C. and below, the chlorine content of a sealing material of the capacitor is not more than 300 ppm to the weight of the sealing material. The impedance ratio of 20&deg; C. to &minus;10&deg; C. at 100 kHz of the aluminum electrolytic capacitor is 4 or less. The present invention can provide a highly reliable aluminum electrolytic capacitor of rated voltage of under 100V, which achieves superior impedance and low temperature properties, and has little risk of ignition even when the electrolytic solution is released.

Aluminum electrolytic capacitor

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Kyoto, Japan

Koichiro Minato