Patents by Inventor Ryuta Kobayakawa

Ryuta Kobayakawa 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).

  • Publication number: 20100297340
    Abstract: There is provided a method for producing a solid electrolytic capacitor having an improved capacitance appearance ratio by forming a conductive polymer layer in a few steps. A method for producing a solid electrolytic capacitor obtained by forming solid electrolyte layer 5 and cathode 6 on dielectric layer 2 formed on anode body 1, which is a porous body of a valve action metal, includes the step of forming precoat layer 3 by the steps of impregnating the porous body with polyacid, water washing, and drying.
    Type: Application
    Filed: May 14, 2010
    Publication date: November 25, 2010
    Applicant: NEC TOKIN CORPORATION
    Inventors: Satoshi SUZUKI, Tomoki NOBUTA, Naoki TAKAHASHI, Yasuhisa SUGAWARA, Ryuta KOBAYAKAWA, Akiko OSHIMA
  • Publication number: 20100254072
    Abstract: In a solid electrolytic capacitor whose cathode is formed by forming an oxide film 2 on an anode-body valve-action metal 1, and forming a conductive polymer layer 3, a graphite layer 4, and a silver layer 5 in succession on the oxide film, the conductive polymer layer 3 contains a sulfonic acid ester compound. In this way, a solid electrolytic capacitor having a low ESR and an excellent moisture resistance and its manufacturing method can be provided.
    Type: Application
    Filed: April 1, 2010
    Publication date: October 7, 2010
    Applicant: NEC TOKIN CORPORATION
    Inventors: Tomoki Nobuta, Yasuhisa Sugawara, Satoshi Suzuki, Naoki Takahashi, Ryuta Kobayakawa
  • Publication number: 20100091432
    Abstract: A conductive polymer composition with excellent water resistance and conductivity, and a solid electrolytic capacitor with low ESR, excellent reliability, and especially moisture resistance. The conductive polymer composition includes a conductive polymer, a polyanion that includes a hydrophilic group, where the polyanion functioning as a dopant of the conductive polymer. At least a part of the hydrophilic group of the polyanion is condensed with an epoxy group in a compound with one epoxy group. A solid electrolytic capacitor of the present invention includes the conductive polymer composition.
    Type: Application
    Filed: September 21, 2009
    Publication date: April 15, 2010
    Applicant: NEC TOKIN CORPORATION
    Inventors: Yasuhisa Sugawara, Tomoki Nobuta, Naoki Takahashi, Ryuta Kobayakawa, Satoshi Suzuki
  • Patent number: 7684172
    Abstract: A solid electrolytic capacitor includes a valve metal formed with an anodized film; an inner conductive polymer film formed on the anodized film; and an outer conductive polymer film formed on the inner conductive polymer film. The outer conductive polymer film is obtained by: preparing a first polymer solution (PEDOT/PSSA); dissolving a predetermined dissolved substance in a non-aqueous solvent, the predetermined dissolved substance being selected from the group consisting of boric acid, 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, 1,3,6-naphthalenetrisulfonic acid, and polystyrenesulfonic acid, and a salt thereof; mixing the dissolved solvent with pure water to obtain an additive solution; adding the additive solution into the first polymer solution to obtain a second polymer solution; and applying the second polymer solution to the inner conductive polymer film.
    Type: Grant
    Filed: November 27, 2007
    Date of Patent: March 23, 2010
    Assignee: NEC TOKIN Corporation
    Inventors: Takeo Kasuga, Yuji Yoshida, Masanori Takahashi, Ryuta Kobayakawa, Takeshi Saito, Koji Sakata, Sadamu Toita, Katsuhiro Yoshida
  • Publication number: 20100033905
    Abstract: The present invention provides a conductive polymer suspension for providing a conductive polymer material having a high conductivity and a method for producing the same, and in particular, a solid electrolytic capacitor having a low ESR and a method for producing the same. The conductive polymer suspension is produced by: synthesizing a conductive polymer by chemical oxidative polymerization of a monomer giving the conductive polymer by using an oxidant in a solvent containing a dopant consisting of a low-molecular organic acid or a salt thereof; purifying the conductive polymer; and mixing the purified conductive polymer and an oxidant in an aqueous solvent containing a polyacid component.
    Type: Application
    Filed: July 28, 2009
    Publication date: February 11, 2010
    Applicant: NEC Tokin Corporation
    Inventors: Ryuta KOBAYAKAWA, Tomoki NOBUTA, Naoki TAKAHASHI, Yasuhisa SUGAWARA, Satoshi SUZUKI, Toshihiko NISHIYAMA
  • Publication number: 20100033906
    Abstract: The present invention provides a conductive polymer suspension for providing a conductive polymer material having a high conductivity and a method for producing the same, and in particular, a solid electrolytic capacitor having a low ESR and a method for producing the same. The conductive polymer suspension can be is produced by: synthesizing a conductive polymer by chemical oxidative polymerization of a monomer giving the conductive polymer by using an oxidant in an aqueous solvent containing a dopant consisting of a low-molecular organic acid or a salt thereof, or a polyacid having a weight average molecular weight of less than 2,000 or a salt thereof.
    Type: Application
    Filed: July 28, 2009
    Publication date: February 11, 2010
    Applicant: NEC Tokin Corporation
    Inventors: Tomoki NOBUTA, Ryuta KOBAYAKAWA, Naoki TAKAHASHI, Yasuhisa SUGAWARA, Satoshi SUZUKI, Toshihiko NISHIYAMA
  • Patent number: 7602602
    Abstract: A conductive polymer having high conductivity and a solid electrolytic capacitor having low ESR are provided. A conductive polymer is synthesized using as a monomer a compound of a dimer to a decamer in which 3-alkyl five-membered heterocyclic rings are bonded at positions 2 and 5, being sterically controlled. Further, this conductive polymer is used as the solid electrolyte of a solid electrolytic capacitor.
    Type: Grant
    Filed: January 27, 2009
    Date of Patent: October 13, 2009
    Assignee: Nec Tokin Corporation
    Inventors: Naoki Takahashi, Ryuta Kobayakawa, Tomoki Nobuta, Yasuhisa Sugawara, Satoshi Suzuki
  • Publication number: 20090225499
    Abstract: A conductive polymer having high conductivity and a solid electrolytic capacitor having low ESR are provided. A conductive polymer is synthesized using as a monomer a compound of a dimer to a decamer in which 3-alkyl five-membered heterocyclic rings are bonded at positions 2 and 5, being sterically controlled. Further, this conductive polymer is used as the solid electrolyte of a solid electrolytic capacitor.
    Type: Application
    Filed: January 27, 2009
    Publication date: September 10, 2009
    Applicant: NEC TOKIN CORPORATION
    Inventors: Naoki TAKAHASHI, Ryuta KOBAYAKAWA, Tomoki NOBUTA, Yasuhisa SUGAWARA, Satoshi SUZUKI
  • Publication number: 20090116172
    Abstract: A solid electrolytic capacitor manufacturing method includes a process of removing a roughened surface layer (10a?) from a distal portion (13) of a metal member (10) and from part of an intermediate portion (12) adjacent to the distal portion (13), a process of forming a resist (40) on the distal portion (13) and the intermediate portion (12) of the metal member (10), a process of forming a conductive polymer layer (30) of a conductive polymer on a proximal portion (11) of the metal member (10), and a process of removing a resist (40?) and a surface layer portion (13?) of the metal member (10) from the distal portion (13) of the metal member (10).
    Type: Application
    Filed: October 31, 2008
    Publication date: May 7, 2009
    Applicant: NEC TOKIN Corporation
    Inventors: Naoki TAKAHASHI, Toshihiko Nishiyama, Satoshi Suzuki, Ryuta Kobayakawa, Tomoki Nobuta
  • Publication number: 20090109603
    Abstract: In a solid electrolytic capacitor including a porous valve-acting metal, an anode conductor has a large number of pores having openings on the surface thereof according to the porosity of the valve-acting metal. A solid electrolyte layer is formed on the surface of the anode conductor so as to be filled in at least a portion of each of the pores and to close the openings thereof. Further, a cathode conductor is formed on the solid electrolyte layer. Preferably, the solid electrolyte layer has a two-layer structure with two layers having different particle sizes.
    Type: Application
    Filed: October 28, 2008
    Publication date: April 30, 2009
    Applicant: NEC TOKIN Corporation
    Inventors: Tomoki NOBUTA, Naoki Takahashi, Ryuta Kobayakawa, Satoshi Suzuki, Toshihiko Nishiyama
  • Publication number: 20080123252
    Abstract: A solid electrolytic capacitor comprising: a valve metal formed with an anodized film; an inner conductive polymer film formed on the anodized film; and an outer conductive polymer film formed on the inner conductive polymer film. The outer conductive polymer film is obtained by: preparing a first polymer solution (PEDOT/PSSA); dissolving a predetermined dissolved substance in a non-aqueous solvent, the predetermined dissolved substance being selected from the group consisting of boric acid, 1-naphthalenesulfonic acid, 2-naphthalenesulfonic acid, 1,3,6-naphthalenetrisulfonic acid, and polystyrenesulfonic acid, and a salt thereof; mixing the dissolved solvent with pure water to obtain an additive solution; adding the additive solution into the first polymer solution to obtain a second polymer solution; and applying the second polymer solution to the inner conductive polymer film.
    Type: Application
    Filed: November 27, 2007
    Publication date: May 29, 2008
    Applicant: NEC TOKIN CORPORATION
    Inventors: Takeo Kasuga, Yuji Yoshida, Masanori Takahashi, Ryuta Kobayakawa, Takeshi Saito, Koji Sakata, Sadamu Toita, Katsuhiro Yoshida