Patents by Inventor Masahiro Yamakawa

Masahiro Yamakawa 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: 8007690
    Abstract: A conductive paste mainly composed of a metal powder, a glass frit, and an organic vehicle. The total content amount of the metal powder and glass frit with respect to the entire conductive paste is 85 wt % or more. The viscosity at a rotational speed of 1 rpm measured at 25° C. with an E type rotating viscometer is 100 Pa·s or more and 400 Pa·s or less.
    Type: Grant
    Filed: May 22, 2006
    Date of Patent: August 30, 2011
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Masahiro Yamakawa, Kohei Shimoda
  • Publication number: 20110193014
    Abstract: The present invention relates to a negative electrode material for a lithium battery comprising a carbonaceous negative electrode active substance having a specific surface area of 1 m2/g or more, a binder formed of styrene-butadiene rubber and a carbon fiber having a fiber diameter of 1 to 1,000 nm; and to a lithium battery using the negative electrode material, which has excellent characteristics, i.e., low electrode resistance, high electrode strength, excellent electrolytic solution permeability, high energy density, and good high-speed charging/discharging performance. The negative electrode material contains carbon fiber in the amount of 0.05 to 20 mass % and the binder formed of styrene-butadiene rubber in 0.1 to 6.0 mass %, and may further contain a thickener such as carboxymethyl cellulose in the amount of 0.3 to 3 mass %.
    Type: Application
    Filed: April 19, 2011
    Publication date: August 11, 2011
    Applicants: SHOWA DENKO K.K., Zeon Corporation
    Inventors: Chiaki SOTOWA, Masataka Takeuchi, Hidekazu Mori, Masahiro Yamakawa
  • Publication number: 20110177407
    Abstract: [Object] To provide an electrochemical reactor that is small in size but high in throughput capacity, does not generate NOx or carbon dioxide, can be operated at a low running cost, is easy to handle during assembling, and has a simple structure and high durability, a method for manufacturing the reactor, a gas decomposing element, an ammonia decomposing element, and a power generator. [Solution] An electrochemical reactor 10 includes a porous anode 2, a porous cathode 5 that is paired with the anode, and an ion conductive material 1 having an ion conductivity and being interposed between the anode and the cathode. The anode 2 includes surface-oxidized metal particle chains 21.
    Type: Application
    Filed: September 17, 2009
    Publication date: July 21, 2011
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Masatoshi Majima, Atsushi Fukunaga, Shinji Inazawa, Toshio Ueda, Motomi Nakata, Hiroki Mori, Masahiro Yamakawa
  • Patent number: 7939600
    Abstract: Provided are a binder for an electric double layer capacitor electrode which gives an electrode having a high electrode density and a high binding force and which comprises a polymer that can give a polymer film having a tensile stress of 2 MPa or less when the film is elongated at the ratio of 100% and having the elongation at break of 450% or more; a binder composition for an electric double layer capacitor electrode and a slurry composition for an electric double layer capacitor electrode which each comprises the binder; an electrode produced by use of the slurry composition; and an electric double layer capacitor which has the electrode so as to exhibit a large electrostatic capacity and a small internal resistance.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: May 10, 2011
    Assignee: Zeon Corporation
    Inventors: Hidekazu Mori, Masahiro Yamakawa, Mayumi Fukumine, Keita Tokura
  • Patent number: 7914704
    Abstract: A binder for an electric double layer capacitor electrode, which includes a copolymer (A) including monomer units derived from at least one compound (a) represented by the following general formula (1): CH2?CR1—COOR2 (1) wherein R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group or a cycloalkyl group, the glass transition temperature obtained by homopolymerizing the compound (a) being less than 0° C., and monomer units derived from at least one compound (b) selected from acrylic acid alkyl esters, methacrylic acid alkyl esters, aromatic vinyl compounds, and ?,?-unsaturated nitrile compounds, the glass transition temperature obtained by homopolymerizing the compound (b) being 0° C. or higher, wherein the total content of the monomer units derived from the compound (a) and those derived from the compound (b) is 90% or more by weight per 100% of the whole copolymer (A), and the glass transition temperature of the copolymer (A) is 10° C.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: March 29, 2011
    Assignee: Zeon Corporation
    Inventors: Masahiro Yamakawa, Hidekazu Mori
  • Patent number: 7897281
    Abstract: The present invention provides a new binder composition for an electrode for an electric double layer capacitor which comprises a binder good in binding force and excellent in heat resistance, an electrode for an electric double layer capacitor having this binder, and an electric double layer capacitor which is high in capacity and is electrochemically stable by use of a binder composition for an electrode for an electric double layer capacitor comprising a binder polymer and water, wherein said binder polymer comprises: 50 to 98% by mole of monomer units (a) derived from a compound represented by the following general formula: CH2?CR1—COOR2 (1) wherein R1 represents a hydrogen atom or an alkyl group, and R2 represents an alkyl group having 2 to 18 carbon atoms or a cycloalkyl group having 3 to 18 carbon atoms, 1 to 30% by mole of monomer units (b) derived from an ?,?-ethylenically unsaturated nitrile compound, and 0.
    Type: Grant
    Filed: March 17, 2004
    Date of Patent: March 1, 2011
    Assignee: Zeon Corporation
    Inventors: Masahiro Yamakawa, Hidekazu Mori
  • Publication number: 20110036726
    Abstract: [Object] To provide a gas decomposition apparatus and a gas decomposition method in which no safety problems occur in spite of the application of a relatively high voltage between an anode and a cathode for the purpose of decomposing odorous gases of many types. [Solution] A catalytic electrode layer 6 that contains a catalyst and is porous; a counter electrode layer 7 that forms a pair with the catalytic electrode; and an electrolyte layer 15 that is sandwiched between the catalytic electrode and the counter electrode and has ion conductivity are included. The catalyst is held by the catalytic electrode in the form of being carried by a carrier containing a conductive material or the catalyst is directly carried by the catalytic electrode. A conductive material in the catalytic electrode, the conductive material being in contact with the catalyst, is not a noncovalent carbon material.
    Type: Application
    Filed: April 2, 2009
    Publication date: February 17, 2011
    Applicant: Sumitomo Electric Industries, Ltd.
    Inventors: Masatoshi Majima, Shinji Inazawa, Koji Nitta, Masahiro Yamakawa, Takayasu Sugihara, Yasuhiro Takeda, Yoshihiro Akahane, Takahiro Imai
  • Publication number: 20100015328
    Abstract: A method of manufacturing an electrode for an electrochemical device is provided with the steps of: supplying, onto a collector, a powdered mixture containing a binder and an active material; and heating the powdered mixture to form an electrode layer on the collector, that allows continuous mass production of electrodes for electrochemical devices.
    Type: Application
    Filed: July 17, 2009
    Publication date: January 21, 2010
    Inventors: Yoshitsugu HIROKAWA, Hidekazu Mori, Masahiro Yamakawa
  • Patent number: 7556747
    Abstract: Provided is a conductive paste which can have high conductivity even if the sintering temperature is 500° C. or less, and which does not cause an interference pattern or crack on a substrate even if a thick film thereof is formed on the substrate. The conductive paste comprises main components including a metal powder, a glass frit, and an organic vehicle. The metal powder is composed of spherical particles (A) having an average primary-particle diameter of 0.1 to 1 ?m and spherical particles (B) having an average primary-particle diameter of 50 nm or less, and the content of spherical particles (A) ranges from 50 to 99 wt % and the content of spherical particles (B) ranges from 1 to 50 wt %. The content of the glass frit ranges from 0.1 wt % to 15 wt % to the total amount of the glass frit and the metal powder. Preferably, the glass frit does not contain lead and has a working point of 500° C. or less, and the average particle diameter thereof is 2 ?m or less.
    Type: Grant
    Filed: July 13, 2004
    Date of Patent: July 7, 2009
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Masahiro Yamakawa, Kohei Shimoda
  • Publication number: 20090107707
    Abstract: A conductive paste is mainly composed of a metal powder, a glass frit, and an organic vehicle. The total content amount of the metal powder and glass frit with respect to the entire conductive paste is 85 wt % or more. The viscosity at a rotational speed of 1 rpm measured at 25° C. with an E type rotating viscometer is 100 Pa·s or more and 400 Pa·s or less.
    Type: Application
    Filed: May 22, 2006
    Publication date: April 30, 2009
    Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.
    Inventors: Masahiro Yamakawa, Kohei Shimoda
  • Patent number: 7510592
    Abstract: A method of producing metal powder by reducing ions of a metal for precipitation by performance of a reducing agent in a liquid-phase reaction system, wherein the metal is precipitated as metal powder particles by being reduced under conditions in which the exchange-current density of an oxidation-reduction reaction between the metal ions and the reducing agent is 100 ?A/cm2 or less, the exchange-current density being determined by the mixed potential theory.
    Type: Grant
    Filed: December 8, 2004
    Date of Patent: March 31, 2009
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Masatoshi Majima, Kohei Shimoda, Issei Okada, Masahiro Yamakawa, Takashi Kasuga
  • Publication number: 20090042001
    Abstract: A conductive paste contains metal powder, an inorganic binder, and an organic vehicle as main ingredients. The organic vehicle includes a solvent having a boiling point of 270° C. or higher, and the proportion of the solvent with respect to the entire solvent included in the organic vehicle is 3 to 100% by weight.
    Type: Application
    Filed: January 18, 2007
    Publication date: February 12, 2009
    Inventors: Masahiro Yamakawa, Kenji Miyazaki
  • Patent number: 7389190
    Abstract: There is provided a testing apparatus for testing a device under test, wherein the testing apparatus is provided with a timing generator for generating a timing signal indicating the timing at which a test signal is applied; a plurality of timing delay units for delaying the timing signal; a plurality of drivers for applying the delayed test signals; a sampler for sampling the test signal and outputting a sample voltage; a comparator for outputting a comparison result indicating whether the sample voltage is higher than the reference voltage; a determination part for determining whether the sample voltage matches the reference voltage; and a timing calibration part for calibrating the delay time caused in the timing signal by the plurality of timing delay units in order to synchronize the timing at which the test signals are applied to the device under test.
    Type: Grant
    Filed: September 8, 2004
    Date of Patent: June 17, 2008
    Assignee: Advantest Corporation
    Inventors: Yoshiharu Umemura, Toshiyuki Okayasu, Toshiaki Awaji, Masahiro Yamakawa
  • Publication number: 20080096109
    Abstract: Disclosed is a composition for electrode comprising (i) a positive electrode active material comprising an iron compound and carbon, and (ii) a copolymer (P) prepared by copolymerization of acrylic acid esters and/or methacrylic acid esters, with an ?,?-unsaturated nitrile compound. Also disclosed is an electrode comprised of an active material layer made of the composition for electrode, and a collector. This electrode can be produced by mixing the positive electrode active material, the copolymer (P), a solvent and an optional thickener, by a mixer to prepare an electrode composition slurry with solid content of 40-90% by weight, coating a collector with the electrode composition slurry, and then, removing the solvent from the thus-formed coating. Further disclosed a battery provided with the electrode.
    Type: Application
    Filed: October 5, 2005
    Publication date: April 24, 2008
    Applicant: ZEON CORPORATION
    Inventors: Mayumi Fukumine, Mitsuhiro Mori, Masahiro Yamakawa, Hidekazu Mori
  • Publication number: 20080011986
    Abstract: A binder for an electric double layer capacitor electrode, which includes a copolymer (A) including monomer units derived from at least one compound (a) represented by the following general formula (1): CH2?CR1—COOR2 ??(1) wherein R1 represents a hydrogen atom or a methyl group, and R2 represents an alkyl group or a cycloalkyl group, the glass transition temperature obtained by homopolymerizing the compound (a) being less than 0° C., and monomer units derived from at least one compound (b) selected from acrylic acid alkyl esters, methacrylic acid alkyl esters, aromatic vinyl compounds, and ?,?-unsaturated nitrile compounds, the glass transition temperature obtained by homopolymerizing the compound (b) being 0° C. or higher, wherein the total content of the monomer units derived from the compound (a) and those derived from the compound (b) is 90% or more by weight per 100% of the whole copolymer (A), and the glass transition temperature of the copolymer (A) is 10° C.
    Type: Application
    Filed: August 4, 2004
    Publication date: January 17, 2008
    Applicant: ZEON CORPORATION
    Inventors: Masahiro Yamakawa, Hidekazu Mori
  • Patent number: 7316864
    Abstract: A slurry composition for electrode comprising a binder, an active material, and a liquid medium, characterized in that the binder comprises a polymer (X) comprising 60 to 95 mole % of repeating units derived from acrylonitrile or methacrylonitrile and 5 to 30 mole % of repeating units derived from at least one kind of a monomer selected from 1-olefins and compounds represented by the following general formula (1): CH2?CR1—COOR2 wherein R1 represents a hydrogen atom or a methyl group and R2 represents an alkyl group; and the liquid medium is capable of dissolving the polymer (X). The slurry composition allows the manufacture of a lithium ion secondary battery having enhanced capacity and good charge-discharge cycle characteristics and good charge-discharge rate characteristics.
    Type: Grant
    Filed: October 25, 2002
    Date of Patent: January 8, 2008
    Assignee: Zeon Corporation
    Inventors: Akira Nakayama, Takao Suzuki, Hidekazu Mori, Katsuya Nakamura, Masahiro Yamakawa
  • Publication number: 20070274023
    Abstract: Provided are a binder for an electric double layer capacitor electrode which gives an electrode having a high electrode density and a high binding force and which comprises a polymer that can give a polymer film having a tensile stress of 2 MPa or less when the film is elongated at the ratio of 100% and having the elongation at break of 450% or more; a binder composition for an electric double layer capacitor electrode and a slurry composition for an electric double layer capacitor electrode which each comprises the binder; an electrode produced by use of the slurry composition; and an electric double layer capacitor which has the electrode so as to exhibit a large electrostatic capacity and a small internal resistance.
    Type: Application
    Filed: October 21, 2004
    Publication date: November 29, 2007
    Applicant: ZEON CORPORATION
    Inventors: Hidekazu Mori, Masahiro Yamakawa, Mayumi Fukumine, Keita Tokura
  • Publication number: 20070275302
    Abstract: The present invention relates to a negative electrode material for a lithium battery characterized by comprising a carbonaceous negative electrode active substance having a specific surface area of 1 m2/g or more, a binder formed of styrene-butadiene rubber and a carbon fiber having a fiber diameter of 1 to 1,000 nm; and to a lithium battery using the negative electrode material, which has excellent characteristics, i.e., low electrode resistance, high electrode strength, excellent electrolytic solution permeability, high energy density, and good high-speed charging/discharging performance. The negative electrode material contains carbon fiber in the amount of 0.05 to 20 mass % and the binder formed of styrene-butadiene rubber in 0.1 to 6.0 mass %, and may further contain a thickner such as carboxymethyl cellulose in the amount of 0.3 to 3 mass %.
    Type: Application
    Filed: December 28, 2004
    Publication date: November 29, 2007
    Inventors: Chiaki Sotowa, Masataka Takeuchi, Hidekazu Mori, Masahiro Yamakawa
  • Publication number: 20070089565
    Abstract: A method of producing metal powder by reducing ions of a metal for precipitation by performance of a reducing agent in a liquid-phase reaction system, wherein the metal is precipitated as metal powder particles by being reduced under conditions in which the exchange-current density of an oxidation-reduction reaction between the metal ions and the reducing agent is 100 ?A/cm2 or less, the exchange-current density being determined by the mixed potential theory.
    Type: Application
    Filed: December 8, 2004
    Publication date: April 26, 2007
    Inventors: Masatoshi Majima, Kohei Shimoda, Issei Okada, Masahiro Yamakawa, Takashi Kasuga
  • Patent number: 7208982
    Abstract: A sampling circuit for compensating the phase difference of a sampling pulse due to a temperature variation to accurately sample input signals is provided. The sampling circuit samples received input signals. The sampling circuit includes a pulse generator for generating a pulse signal according to a timing at which an input signal should be sampled, a step recovery diode for outputting a sampling pulse responsive to the pulse signal, a detector for detecting the value for the input signal according to the sampling pulse, a temperature detecting circuit for detecting the temperature around the step recovery diode and a temperature compensating unit for controlling a timing at which the step recovery diode outputs the sampling pulse based on the temperature detected by the temperature detecting circuit.
    Type: Grant
    Filed: November 10, 2005
    Date of Patent: April 24, 2007
    Assignee: Advantest Corporation
    Inventors: Masahiro Yamakawa, Yoshiharu Umemura, Toshiaki Awaji, Satoshi Shiwa