Showa Denko K.k.

Showa Denko Kabushiki Kaisha

Murata Manufacturing Co., Ltd.

Showa Denka K.k.

Kazumi Naito

Kazuhiro Omori

Shoji Yabe

Nobuyuki Nagato

Katutoshi Tamura

Katsutoshi Tamura

Masahiro Suzuki

Toshiya Kawasaki

Isao Kabe

Kouichi Wada

Atsushi Shimojima

Alan J Heeger

Yukio Kobayashi

Haruo Yoshida

Ryuichi Mitsumoto

Yasuo Tsumita

Shouji Yabe

Masakazu Kobayashi

Toshio Nagashima

Masaaki Nishioka

Yuji Osawa

Hirofumi Fukunaga

Shuji Kozono

Wada Kouichi

A solid electrolytic capacitor is obtained by a method which includes dissolving a polymerizable material for being converted into a conductive polymer in a water-soluble organic solvent to obtain a solution, adding the solution to water while homogenizing the solution to obtain a sol, immersing an anode body having a dielectric layer in the surface of the anode body in the sol, and applying voltage using the anode body as a positive electrode and a counter electrode as a negative electrode placed in the sol to electropolymerize the polymerizable material. An electropolymerizable liquid for producing a conductive polymer, the liquid composed of a sol comprising water, a water-soluble organic solvent, and a polymerizable material for being converted into the conductive polymer.

Method for producing conductive polymer and method for producing solid electrolyte capacitor

Disclosed is a solid electrolytic capacitor article including a lead frame having at least a pair of an anode terminal and a cathode terminal, a capacitor element which is connected to the anode terminal and the cathode terminal, and a silicone resin layer that coats the anode terminal, the cathode terminal, and the exterior surface of the capacitor element connected thereto.

Solid electrolytic capacitor article, solid electrolytic capacitor, lead frame and method for manufacturing solid electrolytic capacitor

A capacitor element including at least an anode body composed of a sintered compact containing tungsten as a main component, a dielectric layer with a smooth surface formed by chemical conversion of the surface of the anode body, and a semiconductor layer laminated on the dielectric layer. The capacitor is obtained by a production method which includes the steps of chemically converting the surface layer of the tungsten powder sintered compact into the dielectric layer in an aqueous solution containing 0.05 to 12% by mass of an oxidant composed of an oxygen-containing compound at a solution temperature of 62&#xb0; C. or less, and removing all or most of water adhering to the inner surface of pores at a temperature of less than the boiling point of water, followed by drying at a temperature of not less than the boiling point of water.

Capacitor element

Disclosed is a solid electrolytic capacitor element including a dielectric layer, a first conductive polymer semiconductor layer, a second conductive polymer semiconductor layer and a conductor layer, formed in that order, on a tungsten anode body having an externally protruding lead wire, and the thickness of the thickest portion of the second conductive polymer semiconductor layer on the lower surface opposite the upper surface from which the lead wire protrudes is thinner than the thickness of the thickest portion of the second conductive polymer semiconductor layer on the side surfaces, and the thickness of the second conductive polymer semiconductor layer on the lower surface is greater than 2 &#x3bc;m and less than 15 &#x3bc;m.

Solid electrolytic capacitor element and method for manufacturing solid electrolytic capacitor element

A solid electrolytic capacitor element which comprises an anode body, a dielectric layer placed so as to cover the anode body, a semiconductor layer placed on the dielectric layer, an insulator layer placed on the semiconductor layer, a carbon layer placed on the insulator layer, and a silver layer placed on the carbon layer, wherein the insulator layer has a part having a thickness of 10 to 100 nm accounting for not less than &#x2154; of the whole insulator layer.

Solid electrolytic capacitor element

An anode body for a capacitor formed by subjecting the sintered body which is obtained by sintering the molded body of tungsten powder to chemical conversion treatment, which anode body is doped with potassium in the amount of 0.003 to 0.3 mass %; a method of producing an anode body for a capacitor formed by subjecting the sintered body which is obtained by sintering the molded body of tungsten powder to chemical conversion treatment, including a process of doping the anode body with potassium in an amount of 0.003 to 0.3 mass %; and a solid electrolytic capacitor using the anode body.

Anode body for solid electrolytic capacitor

An anode body for a solid electrolytic capacitor element, which is an anode body for a solid electrolytic capacitor element having a dielectric layer on the surface of a sintered body, wherein at least a part of the surface of the valve-acting metal particles constituting the sintered body is covered with a dielectric layer, and a part of the dielectric layer on the particle surface has a larger thickness than the other part; and a method for producing the same, in which a sintered body of a valve-acting metal is immersed in an aqueous solution of an oxidizing agent after being subjected to chemical formation, the resulting sintered body is then immersed in water-soluble alcohol and dried, and the oxidizing agent is removed by water washing.

Anode body for solid electrolytic capacitor elements and method for producing same

When forming a conductive polymer layer serving as a cathode of a solid electrolytic capacitor, in order to obtain a high capacitance even with a small number of times of polymerization treatments, a capacitor anode according to the present invention includes a tungsten sintered body () and is provided with a dielectric film (), and in which vanadium oxide is deposited on the surface of the dielectric film ().

Capacitor anode, solid electrolytic capacitor element, solid electrolytic capacitor, and method for producing capacitor anode

An anode body for an electrolytic capacitor, prepared by sintering a tungsten powder to obtain a sintered body and subjecting the obtained sintered body to chemical conversion to form a dielectric layer comprising a tungsten trioxide compound on the surface of the sintered body, wherein the ratio of the hydration water in the tungsten trioxide compound becomes one molecule or less to 10 molecules of the tungsten trioxide compound. Use of the anode body of the present invention enables production of a tungsten capacitor, which is reduced in the capacitance change due to DC voltage (bias dependency).

Anode body for tungsten capacitors

A solid electrolytic capacitor is obtained by a method comprising dissolving a polymerizable material for being converted into a conductive polymer in a water-soluble organic solvent to obtain a solution, adding the solution to water while homogenizing the solution to obtain a sol, immersing an anode body having a dielectric layer in the surface of the anode body in the sol, and applying voltage using the anode body as a positive electrode and a counter electrode as a negative electrode placed in the sol to electropolymerize the polymerizable material. An electropolymerizable liquid for producing a conductive polymer, the liquid composed of a sol comprising water, a water-soluble organic solvent, and a polymerizable material for being converted into the conductive polymer.

A method for finely powdering tungsten powder, which includes: a process for classifying a material tungsten powder into a fine powder having a relatively small average particle diameter and a coarse powder having a relatively large average particle diameter; an oxidation process for forming an oxide film on the particle surface of the coarse powder; and an alkali treatment process for removing the oxide film formed in the oxidation process and a natural oxide film formed on the fine powder with an alkali aqueous solution. Also disclosed is a method for producing ultrafine tungsten powder, which includes obtaining tungsten powder having an average particle diameter of 0.04 to 0.4 &#x3bc;m and a BET specific surface area of 5 to 15 m/g by the above method for finely powdering.

Method for producing ultrafine tungsten powder

A carbon paste including a carbon powder, a resin, and an oxygen releasing oxidizer. The amount of the oxidizer is 3 to 30 parts by mass based on 100 parts by mass of the total amount of the carbon powder and the resin. A solid electrolytic capacitor element is prepared by a method which includes making a valve-action metal powder sintered to obtain an anode body, electrolytically oxidizing a surface of the anode body to chemically convert the surface into a dielectric layer, electrolytic polymerization to form a semiconductor layer of an electro conductive polymer on the dielectric layer, applying the carbon paste onto the semiconductor layer, and drying and hardening the carbon paste to form a carbon layer.

Carbon paste and solid electrolytic capacitor element

A production method efficiently produces a box sealed type solid electrolytic capacitor in which a capacitor element is accommodated in a box-shaped case. The method includes a step of preparing a bottom wall substrate having bottom walls. A step forms cathode anode circuit patterns on the bottom wall substrate. A step prepares a peripheral side wall substrate having peripheral side walls. A step prepares a peripheral side wall substrate in which a plurality of through-holes are provided that correspond to plurality of bottom wall structural portions. A step fixes a capacitor element to each bottom wall structural portion of the bottom wall substrate. A step obtains a capacitor continuous member in which a plurality of capacitor structural portions structuring a solid electrolytic capacitor by attaching an upper lid substrate on the peripheral side wall substrate. A step obtains a plurality of solid electrolytic capacitors by cutting the capacitor continuous member.

Solid electrolytic capacitor, and production method thereof

The present invention provides a method for producing a capacitor element having good LC characteristics, wherein, after a chemical conversion process to form a dielectric layer on the surface layer of an anode body obtained by forming a powder mainly comprising tungsten, followed by sintering, a semiconductor layer and a conductor layer are sequentially formed on the dielectric layer; an etching process is conducted before forming the dielectric layer to remove a natural oxide film formed on the surface layer on the outer surface and on the surface inside the pores of the anode body so as to adjust the film thickness to a range of 0.5 to 5.0 nm; and the chemical conversion process is conducted at a temperature from &#x2212;4 to 18&#xb0; C. for 7 to 110 minutes after reaching a predetermined voltage.

Method for manufacturing tungsten-based capacitor element

A method for producing an anode body in a capacitor, which includes making a molded body by molding a tungsten powder and making an anode body by sintering the molded body, which includes a step of bringing the tungsten powder or the molded body thereof into contact with a solution of a silicon compound before sintering the molded body so as to adjust the silicon content in the anode body to 0.05 to 7 mass %.

Growing community of inventors

Chiba, Japan

Kazumi Naito