Nec Corporation

Takashi Fukaumi

Atsushi Kobayashi

Satoshi Arai

Toshihiko Nishiyama

Kenji Araki

Koji Sakata

Kenichi Takahashi

Yuji Aoki

Tomohide Date

Hiromichi Taniguchi

Shinji Takeoka

Yoshihiko Saiki

Masashi Ohi

Daisuke Takada

Atushi Kobayashi

Takashi Kono

Hitoshi Ishikawa

Eishun Tsuchida

Hiroshi Yageta

Masaharu Satoh

Kimihisa Yamamoto

Tomitaro Hara

Maki Minamoto

Kosuke Amano

Yuuji Aoki

Kennichi Takahashi

Kennji Araki

Kazuaki Fukushima

Eishun Tuchida

Masashi Ooi

Yoshitaka Fujishima

Kumihisa Yamamoto

The present invention provides an electrically conductive polymer layer of a solid electrolytic capacitor, the electrically conductive polymer layer coating a dielectric layer coating an anode with an anode lead which projects outwardly from the anode through the dielectric layer, and the electrically conductive polymer layer being separated by the dielectric layer from the anode lead, wherein the electrically conductive polymer layer has a thicker portion than a remaining portion thereof and the thicker portion extends at least in the vicinity of the anode lead, and the thicker portion is bounded with the remaining portion so that a sloped-boundary loop between the thicker portion and the remaining portion extends to be parallel to a flat plane vertical to a direction along which the anode lead projects through the dielectric layer, whereby the thicker portion continuously extends in a closer side to the anode lead than the remaining portion.

Method of making a solid electrolytic capacitor using a conductive polymer film

A solid electrolyte capacitor having a solid electrolyte layer that is formed of a polymeric product layer of a polymerizable monomer. The polymeric product layer is doped with an organic sulfonic acid selected from the group consisting of an aromatic polysulfonic acid, an organic sulfonic acid having a hydroxy group, an organic sulfonic acid having a carboxyl group, an alicyclic sulfonic acid, and a benzoquinone sulfonic acid.

Solid electrolyte capacitor and method for manufacturing the same

In a solid electrolyte capacitor including a solid electrolyte implemented by a conducting polymer produced by the chemical oxidative polymerization of a polymerization system containing a monomer, a cation serving as an oxidizer, and an anion serving as a dopant, the polymerization system contains the anion in a stoichiometrically excessive amount relative to the cation. The conductivity of a conducting polymer included in the capacitor is prevented from being deteriorated in a high temperature atmosphere, so that a desirable ESR is preserved during 125&deg; C. heat test. In addition, a conductive high polymer layer having an extremely desirable film property is formed. This successfully prevents stresses ascribable to the expansion and contraction of a seal resin from being transferred to the capacitor during heat test, and thereby protects LC and ESR from deterioration.

Solid electrolyte capacitor and method of producing the same

A multilayer structure in a solid electrolyte capacitor. The multilayer structure extends over a pore and a peripheral surface in the vicinity of the pore in a porous surface. The multilayer structure includes a dielectric layer having a first part extending on an inner surface of the pore and a second part extending on an outer surface of the peripheral surface; a first coupling layer extending on the first part of the dielectric layer; a first conductive polymer layer extending on the first coupling layer; a second coupling layer extending on at least the second part of the dielectric layer; and a second conductive polymer layer extending on the second coupling layer so that the second conductive polymer layer extends at least over the peripheral surface.

Solid electrolyte capacitor using conductive polymer

Method of making solid electrolyte capacitor using a conducting polymer solid electrolytic capacitor using a conducting polymer method of making

The object of the present invention is to provide a solid electrolytic capacitor which can prevent an oxidation degradation of a solid electrolyte caused by heat stress and the like during packaging, which has low an ESR, and a production method of the same; in order to achieve this object, the solid electrolytic capacitor of the present invention includes in order an anode, a dielectric coat, a solid electrolyte layer, and a conductive paste layer, with a conductive polymer is used as the solid electrolyte, wherein the conductive paste layer contains acrylic resins and cellulose resins as a binder, and the thickness of the conductive paste layer is in a range of 20 to 40 &mgr;m.

Solid electrolytic capacitor and production method of the same

In a method of making a solid electrolytic capacitor using an oxide film of an electrochemical valve metal as the dielectric and having, as solid electrolytes, first and second conducting polymer layers formed successively on the oxide film, the first and second conducting polymer layers are formed by chemical oxidative polymerization processes using an oxidizing agent, and the first conducting polymer layer (3) is formed from a compound having a lower reaction rate than the compound used to form the second conducting polymer layer (4).

Solid electrolytic capacitor using a conducting polymer

A solid electrolytic capacitor using a conducting polymer to be formed by chemical oxidative polymerization as a solid electrolyte, the capacitor having: a capacitor element which includes a conducting polymer layer with a thickness of 0.02 .mu.m or greater at its central part. A method for making the solid electrolytic capacitor, having the steps of: providing at least two kinds of solutions with different oxidizing-agent concentrations; and adjusting the thickness of a conducting polymer layer at central part of a capacitor element to be 0.02 .mu.m or greater by using first a solution with a lowest oxidizing-agent concentration of the solutions and subsequently a solution with a next lowest oxidizing-agent concentration of the solutions.

Solid electrolytic capacitor and method for making the same

An electrically conductive polymer layer of a solid electrolytic capacitor that coats a dielectric layer that coats an anode. An anode lead projects outwardly from the anode through the dielectric layer, and the electrically conductive polymer layer is separated by the dielectric layer form the anode lead. The electrically conductive polymer layer has a thicker portion than a remaining portion thereof and the thicker portion extends at least in the vicinity of the anode lead, and the thicker portion is bounded with the remaining portion so that a sloped-boundary loop between the thicker portion and the remaining portion extends to be parallel to a flat plane perpendicular to a direction along which the anode lead projects through the dielectric layer, whereby the thicker portion continuously extends close to the anode lead than the remaining portion.

Solid electrolytic capacitor using a conductive polymer film

A fabrication method of a solid electrolytic capacitor is provided, which decreases the leakage current of a solid electrolytic capacitor without deterioration of ESR. This method is comprised of the steps (a) to (e). In the step (a), a capacitor body is formed by a valve metal, the body serving as an anode of the capacitor. In the step (b), an oxide layer of the valve metal is formed to cover a surface of the capacitor body by anodic oxidation, the oxide layer serving as a dielectric of the capacitor. In the step (c), a layer of an organic conducting polymer is formed on the oxide layer, the layer of the organic conducting polymer serving as a solid electrolyte of the capacitor. In the step (d), the capacitor body with the oxide layer and the layer of the organic conducting polymer is immersed in a reoxidation solution, the reoxidation solution containing a mixture of water and alcohol or a mixture of water and ketone as a solvent. In the step (e), a voltage is applied to the capacitor body to reoxidize the oxide layer in the reoxidation solution by anodic oxidation, thereby healing defects of the oxide layer. The amount of alcohol or ketone is preferably 30 vol % to 50 vol %.

Fabrication method of solid electrolytic capacitor using organic

In a method of manufacturing a solid electrolytic capacitor, an oxide film as a dielectric layer is formed on a surface of a sintered body formed from a valve action metal and having an anode lead. A solid electrolytic layer essentially consisting of a conductive polymer is formed on the dielectric layer. In the step of forming the solid electrolytic layer, the sintered body having the dielectric layer is dipped in an oxidant solution, and the oxidant solution on the surface of the extracted sintered body is evaporated. Then, the sintered body is dipped in a monomer solution prepared by dissolving a conductive polymeric monomer in a solution in which the oxidant is not dissolved, and the monomer solution on the surface of the extracted sintered body is evaporated to form the conductive polymer layer.

Method of manufacturing solid electrolytic capacitor

A fabrication method of a solid electrolytic capacitor is provided, which decreases the necessary repetition number of adhesion steps of an oxidizing agent and a monomer of a conducting polymer to a dielectric of the capacitor while keeping the coverage ratio at a satisfactorily high level. A capacitor body with an oxide layer is first immersed into an oxidizer solution at a room temperature under an atmospheric pressure. The oxidizer solution has a viscosity ranging from 100 to 500 cp at room temperature under the atmospheric pressure. Then, the oxidizer solution adhered to the oxide layer is dried to remove a solvent of the adhered solution and to leave the oxidizing agent on the oxide layer. The oxidizing agent left on the oxide layer is in solid phase at room temperature under the atmospheric pressure. The capacitor body with the oxide layer is immersed into a monomer of a conducting polymer. The monomer of the conducting polymer adhered to the oxide layer is polymerized by the oxidizer left on the oxide layer, thereby forming a layer of the conducting polymer on the oxide layer. These steps are repeated until a desired thickness of the polymer layer is accomplished.

Fabrication method of solid electrolytic capacitor

An oxidant solution for synthesizing a heat-resistant electroconductive polymer, composed of a solution of a non-protonic organic solvent and an oxidant of the organic compound iron salt expressed by the following formula:

Oxzidant solution for synthesizing heat-resistant electroconductive

A fabrication method of a solid electrolytic capacitor is provided, which is able to form the surface irregularity of a conductive polymer layer serving as a solid electrolyte with good controllability and good stability. A capacitor body is formed by a valve metal. The body serves as an anode of the capacity. An oxide layer is formed to cover the surface of the capacitor body. The oxide layer serves as a dielectric of the capacitor. A first conductive polymer layer is formed on the oxide layer. The first conductive polymer layer serves as a part of a solid electrolyte of the capacitor. A powder of a conductive polymer is deposited on the first conductive polymer layer by spraying a fluid containing the powder on the first conductive polymer. A second conductive polymer layer is formed on the first conductive polymer layer to cover the deposited powder. The surface of the second conductive polymer layer has irregularities corresponding to the deposited powder. The second conductive polymer layer serves as another part of the solid electrolyte of the capacitor.

A heat resistant derivative conductive polymer containing nitrogen atoms exclusively in units of polyaniline or a derivative thereof contains a sulfonic acid compound as a dopant, and the percentage of sulfonic acid groups per recurring unit of the polyaniline or derivative thereof is set to 28 to 40%. Also, a solid electrolytic capacitor uses a solid electrolyte of polyaniline or derivative thereof containing a sulfonic acid compound as a dopant, wherein the percentage of sulfonic acid groups per recurring unit of polyaniline or derivative thereof is set to 28 to 40%. In this selected range of the concentration of the dopant, the conductivity and the pyrolysis commencement temperature characteristics are excellent.

Growing community of inventors

Tokyo, Japan

Takashi Fukaumi