A liquid electrolyte is disclosed, which contains as an electrolyte a dicarboxylic acid salt of tetramethylammonium in an aprotic polar solvent, with the molar ratio of cations to anions in the electrolyte being adjusted to be within the range of from 1:1.05 to 1:1.75.

An electrolyte for an electrolytic capacitor is disclosed containing an alkyl quarternary ammonium salt of an enol-form of 1,3-diketone compound as solute within an aprotic solvent. The electrolyte exhibits high conductivity while eliminating the drawbacks associated with the presence of water.

An electrolyte for an electrolytic capacitor is disclosed containing an alkyl quarternary ammonium salt of phenol or nitrophenols as solute within an aprotic solvent. The electrolyte exhibits high conductivity while eliminating the drawbacks associated with the presence of water.

An electrolyte for an electrolytic capacitor is disclosed containing an alkyl quarternary ammino salt of an aliphatic saturated monocarboxylic acid as solute within an aprotic solvent. The electrolyte exhibits high conductivity while eliminating the drawbacks associated with the presence of water.

An electrolyte for an electrolytic capacitor is disclosed containing an alkyl quarternary ammonium salt of an enolform of a 1,3-cyclodiketone compound as solute within an aprotic solvent. The electrolyte exhibits high conductivity while eliminating the drawbacks associated with the presence of water.

An electrolytic solution for an electrolytic capacitor is disclosed, comprising a basic solution comprising a mixed solvent of .gamma.-butyrolactone and ethylene glycol having dissolved therein a quaternary alkylammonium salt of phthalic acid, maleic acid or benzoic acid as a solute, the basic solution further containing from 0.5 to 10 parts by weight of colloidal silica and from 0.5 to 8 parts by weight of at least one phosphorus compound selected from dialkyl phosphate and phosphorous acid, pe...

An object of the present invention is to provide an electrolyte for an electrolytic capacitor, which is advantageous not only in that both electric conductivity and withstand voltage property are high, but also in that thermal stability is excellent, and an electrolytic capacitor using the electrolyte. Specifically, the present invention provides an electrolyte for an electrolytic capacitor, comprising a solvent, at least one quaternary amidinium salt selected from the group consisting of a quat...

An electrolyte for an electrolytic capacitor is disclosed, containing a carboxylic acid salt of a cationic nitrogen-containing heterocyclic compound as solute within an aprotic solvent or a mixed solvent comprising major aprotic solvent and minor polyol solvent.

There are provided a solid electrolytic capacitor having a low ESR characteristic and an electrode foil to be used for this electrolytic capacitor. In accordance with the present invention, a capacitor element uses an anode foil with a post-etching void factor of not more than 51% or a cathode foil with another post-etching void factor of not more than 44%, wherein the capacitor element contains a solvent consisting mainly of a water and a water-soluble metal complex being bonded with phosphoric...