The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 23, 2001
Filed:
Oct. 13, 1999
Yuichiro Tsubaki, Uji, JP;
Hiroyuki Matsuura, Fushimi-ku, JP;
Munehiro Morokuma, Neyagawa, JP;
Koichiro Minato, Fushimi-ku, JP;
Yukihiro Nitta, Uji, JP;
Abstract
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 −10° 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° C. to −10° 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.