A tantalum capacitor includes a tantalum body comprising a tantalum sintered body containing tantalum powder, a conductive polymer layer disposed on the tantalum sintered body and including a first filler as a non-conductive particle, and a tantalum wire. The first filler includes a core including at least one metal oxide among BaTiO.sub.3, Al.sub.2O.sub.3, SiO.sub.2 and ZrO.sub.2, and a coating film disposed on a surface of the core.

An electrolytic capacitor includes a capacitor element, a solid electrolyte layer, an electrolyte solution. The capacitor element has an anode foil with a dielectric layer, and a cathode foil. The solid electrolyte layer is provided between the anode foil and the cathode foil. And the capacitor element is impregnated with the electrolyte solution. The cathode foil includes a covering layer that contains at least one metal selected from titanium and nickel or a compound of the at least one metal. And the solid electrolyte layer contains a conductive polymer, a polymer dopant, and a base component.

Provide is an electrolytic capacitor for a middle-to-high voltage application that is equal to or higher than 100 V which suppresses the total amount of gas to be produced in the electrolytic capacitor. The anode foil of the electrolytic capacitor includes an enlarged surface portion provided with tunnel-shape pits formed from the foil surface in the thickness direction of the foil, and a dielectric oxide film formed on the surface of the enlarged surface portion. The cathode body of the electrolytic capacitor includes a cathode foil formed of a valve acting metal, and a carbon layer formed on the cathode foil.

An electrolytic capacitor includes at least one capacitor element. The at least one capacitor element includes: an anode body including an anode lead portion, and a cathode forming portion; a dielectric layer disposed on at least a surface of the cathode forming portion of the anode body; and a cathode part covering at least a part of the dielectric layer. The cathode part includes a solid electrolyte layer that contains a conductive polymer, and covers at least a part of the dielectric layer. A ratio T1/T2 of a thickness T1 of the solid electrolyte layer formed at a corner portion of the anode body to a thickness T2 of the solid electrolyte layer formed at a center portion of a principal surface of the anode body is in a range from 0.8 to 1.7, inclusive, in a cross section of the at least one capacitor element.

A solid electrolyte capacitor includes a sintered body formed by sintering a molded body containing a metal powder; and a solid electrolyte layer disposed on the sintered body, wherein the solid electrolyte layer includes a first layer containing an electrolytic polymerization conductive polymer disposed on the sintered body and a second layer containing a chemical polymerization conductive polymer disposed on the first layer.

A solid electrolyte capacitor includes a sintered body formed by sintering a molded body containing metal powder; and a conductive polymer layer disposed above the sintered body. A ratio (t2/t1) of a thickness (t2) of the conductive polymer layer in an edge portion of the sintered body to a thickness (t1) of the conductive polymer layer in a central portion of the sintered body satisfies 0.35≤t2/t1≤0.9.

A cathode and an electrolytic capacitor including the cathode which can suppress production of hydrogen gas are provided. The cathode of the electrolytic capacitor includes cathode foil formed of valve action metal and a conductive layer formed on a surface of the cathode foil. A natural immersion potential of the cathode foil when immersed in an electrolyte solution is at a higher side than a natural immersion potential of reference cathode foil formed of the valve action metal with purity of 99.9%.

A cathode and an electrolytic capacitor including the cathode which can suppress production of hydrogen gas are provided. The cathode of the electrolytic capacitor comprising cathode foil formed of valve action metal, and a conductive layer formed on a surface of the cathode foil. When current in a range of current density of leakage current of the electrolytic capacitor flows by electrochemical polarization, potential corresponding to said current is at a higher side than a natural immersion potential of reference cathode foil formed of the valve action metal with purity of 99.9%.

The present invention relates to a capacitor having a metal current collector, a conductive adhesion layer applied on the metal current collector, and an electrode active layer applied on the conductive adhesion layer, wherein the adhesion layer comprises a conductive non-carbide metal compound, particularly a metal oxide or metal nitride. The present invention further relates to a method of manufacture thereof as well a medical device comprising such capacitor.

Provided is a solid electrolytic capacitor having large capacitance, low ESR, and superior high-frequency characteristics and high-temperature endurance. The solid electrolytic capacitor is provided with: a cathode 10 having a cathode substrate 11 made of a valve metal and having an etching pit 11a; an oxide layer 12 made of an oxide of the valve metal provided on a surface of the cathode substrate 11, and a carbon coating layer 13 provided on a surface of the oxide layer 12, the carbon coating layer 13 including carbon particles and having an entry area 13a that enters the etching pit 11a and a penetration area 13b that penetrates through the oxide layer 12 and conducts with the cathode substrate 11; an anode having an anode substrate made of a valve metal, and a dielectric layer provided on a surface of the anode substrate and made of an oxide of the valve metal that composes the anode substrate; and a solid electrolyte layer including a conductive polymer provided between the carbon coating layer of the cathode and the dielectric layer of the anode.