Showa Denko K.k.

Showa Denko Kabushiki Kaisha

Murata Manufacturing Co., Ltd.

Katsuhiko Yamazaki

Atsushi Sakai

Yuji Furuta

Ryuji Monden

Hiroshi Konuma

Koro Shirane

Hideki Ohata

Toru Sawaguchi

Yoshiaki Ikenoue

Hideko Ohata

Tatsuo Obata

Tamotsu Yamashita

Takashi Ichimura

Takenori Umikawa

Masakazu Yagi

Eiji Komazawa

A formed substrate, wherein the surface of the valve-acting metal having a dielectric film is at least partially covered with an oxide comprising Si, valve-acting metal element and oxygen, preferably, wherein the content of Si in the formed foil having an aluminum oxide dielectric film decreases continuously from the surface of the dielectric film toward the inner part in some regions in the aluminum dielectric film thickness; a method for producing the formed substrate; and a solid electrolytic capacitor comprising a solid electrolyte on the formed substrate. A solid electrolytic capacitor manufactured by using a formed substrate according to the present invention, improved in adhesion to an electrically conducting polymer (solid electrolyte) with its area coverage contacting the polymer being sufficiently large, is increased in the electrostatic capacitance among individual capacitors and improved in the LC yield as compared with capacitors otherwise manufactured.

Formed substrate used for solid electrolytic capacitor, production method thereof and solid electrolytic capacitor using the substrate

A solid electrolytic capacitor includes a valve acting metal having microfine pores, a dielectric film formed on a surface of the valve acting metal, and a solid electrolyte layer provided on the dielectric film, in which at least a portion of the solid electrolyte layer is of a lamellar structure. In particular, a solid electrolytic capacitor includes an electrically conducting polymer having a specified condensed ring structure containing (1) a solid electrolyte layer containing a sulfoquinone anion, and (2) a solid electrolyte layer containing an anthracenesulfonate ion and other anion.

Solid electrolytic capacitor and method for producing the same

A solid electrolytic capacitor comprises an electrically conducting polymer composition formed on the surface of an oxide film which is formed on a valve-acting metal, by specifying the viscosity of an oxidizing agent solution and/or a monomer solution, particularly by specifying the viscosity to less than about 100 cp. A solid electrolytic capacitor can comprise an electroconducting polymer composition formed on the surface of an oxide film layer which is formed on a valve-acting metal, wherein a monomer compound or a derivative thereof as a repeating unit is polymerized by setting the humidity in the atmosphere to from about 10% to less than about 60%.

The present invention relates to a solid electrolytic capacitor comprising a solid electrolyte layer and an electrically conducting layer comprising metallic powder or an electrically conducting layer comprising an electrically conducting carbon layer and a layer formed thereon and comprising metallic powder in which at least one of said layers contains a rubber-like elastic material; a production process thereof; a solid electrolyte for use in the solid electrolytic capacitor; a production process of the solid electrolyte; an electrically conducting paste for use in the solid electrolytic capacitor; and an electrically carbon conducting paste for use in the solid electrolytic capacitor. The solid electrolytic capacitor of the present invention can be made compact and can be endowed with high-capacitance and low-impedance and is excellent in external force-relaxing properties, productivity, heat resistance and moisture resistance, etc.

A method for producing a solid electrolytic capacitor, involving a step of loading a metal oxide on at least a part of the surface in the anode part of a capacitor element having a valve-acting metal substrate having there on a solid electrolyte, the valve-acting metal substrate having a dielectric film obtained by the electrochemical forming, and a solid electrolytic capacitor obtained by stacking two or more single plate capacitor elements having a metal oxide on at least a part of the surface in the anode part of a capacitor element comprising a valve-acting metal substrate having thereon a solid electrolyte, the valve-acting metal substrate having a dielectric film obtained by the electrochemical forming.

To provide a solid electrolytic capacitor where solid electrolyte is formed at the cut end part and at the masking part to a larger thickness than in other parts, where the adhesion of the solid electrolyte formed on the valve acting metal oxide film is improved, and whereby the capacitor is highly stabilized in various basic properties such as capacitance, dielectric loss (tan &#x3b4;), leakage current and short circuit defective ratio and also in the reflow soldering heat resistance and moisture resistance load characteristics. These solid electrolytic capacitor can be obtained by forming electrically conducting polymer on a dielectric film by specifying time for dipping of the surface of a valve actiong metal porous body with a solution containing a monomer and with a solution containing an oxidizing agent, time for vaporization of the solvent of the solution containing a monomer, and polymerization conditions after dipping of the solution containing an oxidizing agent.

A solid electrolytic capacitor includes a valve acting metal having microfine pores, a dielectric film formed on a surface of the valve acting metal, and a solid electrolyte layer provided on the dielectric film, in which at least a portion of the solid electrolyte layer is of a lamellar structure. In particular, a solid electrolytic capacitor includes an electrically conducting polymer having a specified condensed ring structure containing (1) a solid electrolyte layer containing a sulfoquinone anion having a sulfo anion group and a quinone structure and other anion, and (2) a solid electrolyte layer containing an anthracenesulfonate ion and other anion.

A solid electrolytic capacitor comprises a porous valve acting metal having formed thereon a dielectric film and a solid electrolyte formed on the dielectric film. The solid electrolyte occupies from 10 to 95% of the space within a pore of the porous metal.

A solid electrolytic capacitor comprising (1) an electrically conducting polymer composition formed on the surface of an oxide film which is formed on a valve-acting metal, by specifying the viscosity of an oxidizing agent solution and/or a monomer solution, particularly by specifying the viscosity to less than about 100 cp, (2) an electroconducting polymer composition formed on the surface of an oxide film layer which is formed on a valve-acting metal, wherein the electroconducting polymer layer comprising a monomer compound or a derivative thereof as a repeating unit and also containing an anionic dopant is polymerized by setting the humidity in the atmosphere to from about 10% to less than about 60%; (3) an anode body having provided on the outer surface thereof a solid electrolyte formed of an electrically conducting polymer containing a lamellar structure, wherein the solid electrolyte provided on the dielectric film formed on a valve acting metal occupies from about 10 to about 95% of the space in a pore of the electrode, and (4) a method for producing a solid electrolytic capacitor comprising forming a dielectric film on a porous valve acting metal and forming a solid electrolyte in the dielectric film, wherein the solid electrolyte is formed to cover about 60% or more of the dielectric film.

An object of the present invention is to provide a solid electrolytic capacitor with excellent electrostatic capacitance and reduced dispersion of capabilities by treating the surface of a chemically formed aluminum film to form a dielectric film which is in contact an electrically conducting substance provided thereon with sufficiently high adhesion. Another object of the present invention is to provide a method for producing the solid electrolytic capacitor, which includes providing an organic electrically conducting polymer as a solid electrolyte on a chemically formed aluminum substrate having thereon an aluminum oxide dielectric film, where a chemically formed aluminum substrate, which was cut into a predetermined shape, is treated with an aqueous acid solution to dissolve a part of the dielectric film on the substrate surface. The present invention also provides an aluminum solid electrolytic capacitor obtained by the method, and a chemically formed aluminum substrate for aluminum solid electrolytic capacitors.

The present invention provides a solid electrolytic capacitor having a structure that relieves thermal stress, prevents leakage current, exhibits low impedance and ensures high reliability. The solid electrolytic capacitor element has a valve-acting metal substrate with a dielectric film and an edge part acting as an anode, an insulating layer circumferentially provided on the substrate, a solid electrolyte layer and an electrically conducting layer having a carbon paste layer and a metal powder-containing electrically conducting layer formed in this order on the entire substrate surface opposite to the anode with respect to the insulating layer and acting as a cathode. The electrically conducting layer is provided within a region of the carbon paste layer or with a spacing from the cathode side edge part of the insulating layer. The present invention also provides a method for producing the element, and a solid electrolytic capacitor using the element.

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Nagano, Japan

Katsuhiko Yamazaki