Abstract: An electrolytic capacitor has a capacitor element formed from an anode foil, a cathode foil opposed to the anode foil and a release paper sandwiched between the anode foil and the cathode foil, and an electrolytic solution, the content of cation(s) in said release paper being not more than 500 ppm. The electrolytic capacitor has a low impedance, excellent low-temperature stability and heat resistance, and good working life characterstics.

Abstract: An electrolytic solution for an electrolytic capacitor, which includes (1) a solvent made up of 20 to 80% by weight of an organic solvent and 80 to 20% by weight of water, (2) at least one electrolyte selected from the group consisting of carboxylic acids, salts of carboxylic acids, inorganic acids, and salts of inorganic acids, and (3) a chelate compound. Preferably, an organic acid or salt thereof and an inorganic acid or salt thereof are used in combination.

Abstract: An electrolytic solution for use in an electrolytic capacitor, having a solution containing a solvent consisting of 20 to 80% by weight of an organic solvent and 80 to 20% by weight of water, and at least one electrolyte selected from a carboxylic acid or a salt thereof and an inorganic acid or a salt thereof, having added thereto at least on nitro compound selected from nitrophenol, nitrobenzoic acid, dinitrobenzoic acid, nitroacetophenone and nitroanisole. The electrolytic solution has a low impedance and excellent low-temperature stability, along with good working life characteristics, and it can also exhibit an excellent hydrogen gas absorption function when an electrolytic solution contains a highly increased amount of water in its mixed solvent or when an electrolytic capacitor is used under high temperature conditions.