Patents by Inventor Emiko Igaki

Emiko Igaki has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6324051
    Abstract: A solid electrolytic capacitor includes a capacitor element having an anode of a valve action metal, an oxide film layer formed on the surface of the anode, a solid electrolytic layer formed on the oxide film layer and a cathode electrically connected to the solid electrolytic layer, and also a packaging resin formed to cover the capacitor element. An intermediate layer to relieve stress is arranged in at least one part of the interface between the cathode and the packaging resin. The intermediate layer is deformed and/or peels to relieve stress caused by heat applied while mounting the capacitor element on a substrate.
    Type: Grant
    Filed: October 26, 2000
    Date of Patent: November 27, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Emiko Igaki, Masakazu Tanahashi, Chiharu Hayashi, Yoshiki Hashimoto
  • Patent number: 6310765
    Abstract: The invention has an object to reduce the impedance and to improve the responsiveness at high frequencies in an electrolytic capacitor having an conducting polymer layer as the cathode. A cathode collector is directly joined with the surface of the dielectric of a valvular metal porous body for anode using a conducting polymer layer but not through various binding layers (for example, a carbon layer and a silver layer) thereby reducing the impedance. A cathode collector is disposed adjacent and opposite to a porous valvular metal foil for anode. This structure ensures that the collecting area is enlarged. In this case, a cathode collector may be directly joined with the surface of the dielectric of a valvular metal porous body for anode using an conducting polymer layer but not through various binding layers thereby reducing the total impedance.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: October 30, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masakazu Tanahashi, Emiko Igaki
  • Publication number: 20010030848
    Abstract: There is provided a solid electrolytic capacitor including an anode body formed of a valve-action metal with a dielectric oxide coating layer formed on its surface, a cathode body, and an electroconductive polymer layer disposed between the anode body and the cathode body. The electroconductive polymer layer contains a softener for softening the electroconductive polymer layer, so that a solid electrolytic capacitor is provided that has small variations in characteristics, a lower equivalent series resistance (ESR), and an excellent high frequency property. In addition, when the anode and cathode of a solid electrolytic capacitor including an electroconductive polymer as a solid electrolyte are joined to each other, a lower ESR can be obtained under a lower pressure, and the electroconductive polymer layer can be prevented from being peeled off.
    Type: Application
    Filed: April 9, 2001
    Publication date: October 18, 2001
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masashi Shoji, Seigo Shiraishi, Emiko Igaki, Masakazu Tanahashi, Mikinari Shimada
  • Publication number: 20010003501
    Abstract: A solid electrolytic capacitor includes an anode element made of a valve action metal, a dielectric oxide film formed on a surface of the anode element, a solid electrolytic layer formed on a surface of the dielectric oxide film, and a cathode layer formed on a surface of the solid electrolytic layer. The solid electrolytic layer has an iron concentration not greater than 100 ppm. Alternatively or in combination therewith, a weight fraction of residues in the solid electrolytic layer is smaller than 5 wt %. The polymerization residue is an oxidizing agent and a monomer that is produced when such solid electrolytic layer is formed.
    Type: Application
    Filed: December 1, 2000
    Publication date: June 14, 2001
    Inventors: Chiharu Hayashi, Yasunobu Tsuji, Hisataka Kato, Kazuo Kawahito, Yoshiki Hashimoto, Emiko Igaki, Hiroshi Shimada, Mitsuo Terada
  • Patent number: 6239965
    Abstract: The present invention provides an electrolytic capacitor having a large capacitance sufficiently close to its design capacitance, and a method of easily producing such an electrolytic capacitor. In this method, a cathode-side conductive polymer layer or a electrolyzing electrode is formed on at least one side surface of an anode valve metal foil having through holes 20 and a coarsened surface, electrolysis is carried out in a conductive monomer solution, with the polymer layer used as the anode, and an electrolytically-formed conductive polymer layer is formed on the surface of the dielectric oxide film of the valve metal foil, thereby obtaining an electrolytic capacitor. As a result, it is possible to easily obtain an electrolytic capacitor having a large capacitance sufficiently close to its design capacitance.
    Type: Grant
    Filed: May 24, 1999
    Date of Patent: May 29, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Seigo Shiraishi, Emiko Igaki, Masakazu Tanahashi
  • Patent number: 6224639
    Abstract: The present invention provides a method of producing an electrolytic capacitor including a porous anode and a solid electrolyte made of a conductive polymer, which can improve coating properties of the conductive polymer on an external surface of the porous anode and productivity. By controlling a polymerization rate, it is possible to sufficiently coat the external surface of the porous anode and fill inner spaces of a lot of pores of the porous anode with the conductive polymer with less numbers of polymerization in comparison with a method of the prior art, thereby obtaining an electrolytic capacitor with small leak current and high reliability.
    Type: Grant
    Filed: July 7, 1999
    Date of Patent: May 1, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takahiro Hamada, Emiko Igaki, Masakazu Tanahashi, Yasunobu Tsuji, Chiharu Hayashi, Yoshihiko Tsujikawa
  • Patent number: 6185091
    Abstract: Anodic valve metal foils, roughened and provided with dielectric layers, and collector metal foils (metal foils for collector) are laminated alternately to cross with cathodic electroconductive polymer layers therebetween. Anodic terminals and cathodic terminals are connected with the respective ends of the metal foils. For the anodic valve metal foils, an aluminum foil whose internal is an unroughened bulk metal layer is used. The collector metal foil is selected from the group consisting of an Al foil similar to the anodic valve metal foil, an Ni foil, a Cu foil, and an aluminum foil including carbon. As a result, a four-terminal capacitor to provide high capacitance, low impedance, high current-carrying capacity and less heat generation, as well as low ESR and low ESL, is obtained.
    Type: Grant
    Filed: February 8, 1999
    Date of Patent: February 6, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masakazu Tanahashi, Mikinari Shimada, Emiko Igaki
  • Patent number: 6134099
    Abstract: An electrolytic capacitor in which an conducting polymer as a cathode of the electrolytic capacitor is formed as a homogeneous and densified film on the dielectric layer even extending to the inside of pores of a valvular metal porous body and which obtains a high rate of inducing the capacitance, and have low impedance and high responsiveness at high frequencies. A chemical oxidation polymerization method is utilized to form an conducting polymer layer even extending to the inside of pores of the capacitor element. First, a polymerization reaction is performed in a solution excluding an organic acid-type dopant to form an conducting polymer layer as a densified film on a dielectric layer extending from the surface of the porous body to every inside portions of pores in the pretreatment.
    Type: Grant
    Filed: June 3, 1998
    Date of Patent: October 17, 2000
    Assignee: Matsushita Electric Industrial
    Inventors: Emiko Igaki, Masakazu Tanahashi, Chiharu Hayashi
  • Patent number: 6088218
    Abstract: The present invention provides a method for producing an electrolytic capacitor including a porous body of a valve metal, an oxide film on a surface of the valve metal, and a conductive polymer layer on a surface of the oxide film. The step of forming the conductive polymer layer on the surface of the oxide film includes the steps of dipping the porous body in a monomer solution; lifting the porous body from the monomer solution and dipping the porous body in an oxidizing solution; and lifting the porous body from the oxidizing solution and allowing the porous body to stand. In the step of dipping the porous body in the oxidizing solution, a period for which the porous body is dipped in the oxidizing solution is equal to or shorter than a period in which 30% of the monomer contained in pores of the porous body diffuses and flows into the oxidizing solution. Alternatively, the volume of the oxidizing solution can be less than three times that of the porous body.
    Type: Grant
    Filed: October 27, 1998
    Date of Patent: July 11, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takahiro Hamada, Emiko Igaki, Masakazu Tanahashi, Chiharu Hayashi, Yasunobu Tsuji
  • Patent number: 5561828
    Abstract: A method of manufacturing a ceramic electronic part includes the steps of: firing Pd electrodes or alloy electrodes containing Pd as a primary metal along with ceramics in the atmosphere in which Pd cannot be oxidized within the range (I) of oxidizing temperature of Pd in air; and firing the Pd electrodes or alloy electrodes along with the ceramics in air within the range (II) of deoxidizing temperature of PdO in air. The method can manufacture a ceramic electronic part, such as a multilayer ceramic capacitor, including Pd electrodes or alloy electrodes which contain Pd as a primary metal without forming internal defects inside the ceramic electronic part and reducing its properties.
    Type: Grant
    Filed: August 29, 1994
    Date of Patent: October 1, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Emiko Igaki, Masakazu Tanahashi, Takashi Iguchi, Yoichi Okinaka