Patents by Inventor Masakazu Tanahashi

Masakazu Tanahashi 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: 6392869
    Abstract: A solid electrolytic capacitor capable of realizing miniaturization and large capacitance and obtaining the connection, in particular electric connection between the anodes, with low resistance and high reliability. A solid electrolytic capacitor includes: a laminate including a plurality of capacitor units in which a dielectric layer and a solid electrolytic layer are laminated in this order on a predetermined surface of an anode made of a valve metal; a sealing body for sealing the laminate; and an anodic conductive elastic body formed outside the sealing body and electrically connected to the anode. The anodes are adhered to each other via the conductive elastic body. In the solid electrolytic capacitor, a part of the anode is exposed to the outside of the sealing portion and the exposed portion is covered with a plating layer, and electrically connected to the anodic conductive elastic body via the covered exposed portion.
    Type: Grant
    Filed: May 23, 2001
    Date of Patent: May 21, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Seigo Shiraishi, Emiko Igaki, Masakazu Tanahashi, Mikinari Shimada, Norihisa Takahara, Yasuhiko Nakada, Keizou Nakagawa, Hideki Masumi, Eiji Yamashita
  • Publication number: 20020036447
    Abstract: A piezoelectric composite is formed from a piezoelectric precursor prepared by mixing a powder containing piezoelectric material with a binder material and a gap forming material filling a gap formed to the piezoelectric precursor. The gap forming material is then removed from the thus formed piezoelectric composite, thereby forming a piezoelectric element.
    Type: Application
    Filed: September 28, 2001
    Publication date: March 28, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hidetomo Nagahara, Toshiharu Sato, Akihisa Adachi, Kiyohide Amemiya, Kazuhide Shioya, Emiko Igaki, Masakazu Tanahashi
  • Patent number: 6361572
    Abstract: Disclosed is a method of making an electrolytic capacitor including the steps of forming a cathode by depositing a homogeneous and densified conducting polymer on a dielectric layer of a valvular metal porous anode. The conducting polymer is formed of two layers by chemical oxidation polymerization. The first conductive polymer layer is formed in the pretreatment step using a solution excluding an organic acid-type dopant, the polymer is efficiently formed on the inner surface of the pores of the anode and the second conductive polymer layer is formed in the primary treatment step on the first conductive polymer layer, using a solution containing an organic acid-type dopant. The resultant capacitor obtains a high capacitance, a low impedance, and a high responsiveness at high frequencies.
    Type: Grant
    Filed: July 14, 2000
    Date of Patent: March 26, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Emiko Igaki, Masakazu Tanahashi, Chiharu Hayashi
  • Patent number: 6351371
    Abstract: An anodic electrode for an electrolytic capacitor having high capacitance with low-resistance properties at high frequencies and capable of carrying large current, and a process of producing the same. Such an anodic electrode for electrolytic capacitor includes a porous body having micropores to be formed with a dielectric layer therein and to be filled with electrolyte therein, wherein the porous body includes a laminate of a plurality of sinter layers having the micropores formed from valve metal particles. The laminate includes multilaminarly smaller micropore-size regions and larger micropore-size regions to form electric conductive passages between the small micropore-size regions and side surfaces of the porous body to reduce resistance of the capacitor and also increase capacitance by utilizing the smaller micropores-size regions for capacitor effectively.
    Type: Grant
    Filed: April 14, 2000
    Date of Patent: February 26, 2002
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tsunenori Yoshida, Kenji Hoshino, Masakazu Tanahashi, Yoshihiro Higuchi
  • Publication number: 20020011919
    Abstract: An electrode for a PTC thermistor of the present invention includes a base layer having electrical conductivity and a sintered layer formed on the base layer. The sintered layer is formed by sintering a conductive powder and has electrical conductivity, and has roughness on a surface thereof. Thus, the present invention can provide an electrode for a PTC thermistor that has a large adhesion to the conductive polymer and can be produced easily.
    Type: Application
    Filed: February 5, 2001
    Publication date: January 31, 2002
    Applicant: Matsushita Electric Industrial Co. Ltd.
    Inventors: Masahiro Ito, Masakazu Tanahashi, Toshiro Kume, Kouichi Morimoto, Junji Kojima, Emiko Igaki
  • Publication number: 20020001169
    Abstract: A solid electrolytic capacitor capable of realizing miniaturization and large capacitance and obtaining the connection, in particular electric connection between the anodes, with low resistance and high reliability. A solid electrolytic capacitor includes: a laminate including a plurality of capacitor units in which a dielectric layer and a solid electrolytic layer are laminated in this order on a predetermined surface of an anode made of a valve metal; a sealing body for sealing the laminate; and an anodic conductive elastic body formed outside the sealing body and electrically connected to the anode. The anodes are adhered to each other via the conductive elastic body. In the solid electrolytic capacitor, a part of the anode is exposed to the outside of the sealing portion and the exposed portion is covered with a plating layer, and electrically connected to the anodic conductive elastic body via the covered exposed portion.
    Type: Application
    Filed: May 23, 2001
    Publication date: January 3, 2002
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Seigo Shiraishi, Emiko Igaki, Masakazu Tanahashi, Mikinari Shimada, Norihisa Takahara, Yasuhiko Nakada, Keizou Nakagawa, Hideki Masumi, Eiji Yamashita
  • Publication number: 20010048583
    Abstract: An aluminum electrolytic capacitor includes a case, a sealant for sealing the case, a separator, a cathode, an anode, and an electrolyte sealed in the case, and an anode lead connected to the anode, wherein the cathode includes an aluminum foil, and a solid compound having a function of keeping the pH of the electrolyte constant further is provided in the case.
    Type: Application
    Filed: May 25, 2001
    Publication date: December 6, 2001
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuhiko Nakada, Masakazu Tanahashi, Emiko Igaki, Mikinari Shimada
  • 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
  • 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: 6205657
    Abstract: A printed circuit board includes insulating layers formed by impregnating a base material with a resin and a metal foil pattern formed on a desired layer of the insulating layers. Ions for forming a hardly soluble metal salt by combining with metal ions free from a portion of the board or a sulfur-containing compound for reacting with the metal ion are present in the insulating layer or on a surface of the metal foil pattern. Furthermore, a method for producing the printed circuit board includes any one of the steps of adding the ions or the sulfur-containing compound to the resin varnish, impregnating a base material with the solution of the ions or the sulfur-containing compound, or applying the solution onto the surface of the metal foil pattern, in order to allow the ions or the sulfur-containing compound to exist in the printed circuit board.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: March 27, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshihiro Kawakita, Seiichi Nakatani, Masakazu Tanahashi
  • 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: 6174589
    Abstract: A printed circuit board includes insulating layers formed by impregnating a base material with a resin and a metal foil pattern formed on a desired layer of the insulating layers. Ions for forming a hardly soluble metal salt by combining with metal ions free from a portion of the board or a sulfur-containing compound for reacting with the metal ion are present in the insulating layer or on a surface of the metal foil pattern. Furthermore, a method for producing the printed circuit board includes any one of the steps of adding the ions or the sulfur-containing compound to the resin varnish, impregnating a base material with the solution of the ions or the sulfur-containing compound, or applying the solution onto the surface of the metal foil pattern, in order to allow the ions or the sulfur-containing compound to exist in the printed circuit board.
    Type: Grant
    Filed: September 23, 1998
    Date of Patent: January 16, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshihiro Kawakita, Seiichi Nakatani, Masakazu Tanahashi
  • 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: 6120937
    Abstract: In a positive electrode for an alkaline storage battery, a layer is formed between a porous substrate as a core material and an active material including nickel hydroxide filled into the porous substrate. The layer includes an oxide containing cobalt and nickel and/or a hydroxide containing cobalt and nickel. In the hydroxide, the average of an oxidation number of a metal is more than +II. The layer has a high electric conductivity while keeping the high corrosion resistance. A utilization rate of the active material can be improved due to the high electric conductivity. An alkaline storage battery including such an electrode has a good cycle property.
    Type: Grant
    Filed: May 11, 1998
    Date of Patent: September 19, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tamao Kojima, Munehiro Tabata, Tomoyuki Washizaki, Masakazu Tanahashi, Yoshiki Murakami, Satoshi Kaida, Masayoshi Maruta
  • Patent number: 6113755
    Abstract: This invention provides an apparatus for producing an electrode foil for use in aluminum electrolytic capacitors with which a high capacitance is obtained while the distortion of the foil and the leakage current can be controlled. At least two electrode plates as cathode are disposed in an electrolytic tank containing an electrolytic solution, and a direct current is supplied between an aluminum foil as anode and the electrode plates. Anodization is conducted continuously by turning the direction of the aluminum foil via rollers and conveying the foil between the electrode plates. During this treatment, the length and the position of the effective sections of the electrode plates are adjusted to keep the length to be at most two-thirds of the distance between an area near the surface of the electrolytic solution and the upper part of the bottom roller, so that the peak value of the anodizing current density appears not at the surface of the electrolytic solution but in the electrolytic solution.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: September 5, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masakazu Tanahashi, Kounosuke Hashio, Mitsuhisa Yoshimura, Daisuke Suzuki, Masanori Okabayashi, Shinji Kabeya
  • Patent number: 6099709
    Abstract: This invention provides an apparatus for producing an electrode foil for use in aluminum electrolytic capacitors with which a high capacitance is obtained while the distortion of the foil and the leakage current can be controlled. At least two electrode plates as cathode are disposed in an electrolytic tank containing an electrolytic solution, and a direct current is supplied between an aluminum foil as anode and the electrode plates. Anodization is conducted continuously by turning the direction of the aluminum foil via rollers and conveying the foil between the electrode plates. During this treatment, the length and the position of the effective sections of the electrode plates are adjusted to keep the length to be at most two-thirds of the distance between an area near the surface of the electrolytic solution and the upper part of the bottom roller, so that the peak value of the anodizing current density appears not at the surface of the electrolytic solution but in the electrolytic solution.
    Type: Grant
    Filed: May 15, 1996
    Date of Patent: August 8, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masakazu Tanahashi, Kounosuke Hashio, Mitsuhisa Yoshimura, Daisuke Suzuki, Masanori Okabayashi, Shinji Kabeya
  • 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