Patents by Inventor Hirokazu Yukawa

Hirokazu Yukawa 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: 11692047
    Abstract: A method for producing low molecular weight polytetrafluoroethylene which includes: (1) feeding into an airtight container in the absence of oxygen: high molecular weight polytetrafluoroethylene: and a halogenated polymer having a halogen atom other than a fluorine atom; and (2) irradiating the high molecular weight polytetrafluoroethylene to provide low molecular weight polytetrafluoroethylene having a melt viscosity at 380° C. of 1.0×102 to 7.0×105 Pa·s.
    Type: Grant
    Filed: February 5, 2019
    Date of Patent: July 4, 2023
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Masayuki Tsuji, Yuuji Tanaka, Hirokazu Yukawa
  • Publication number: 20220297394
    Abstract: A method of producing a composite material including carbon fiber and a melt-fabricable fluororesin, the method including: (1) preparing a prepreg by heating and compressing a stack of opened carbon fiber and a film of a melt-fabricable fluororesin at a temperature not lower than a melting point of the fluororesin, the film having a back tension set to 3.0 N/cm2 or less; and (2) preparing a composite material by heating and compressing one or more sheets or pieces of the prepreg stacked in a thickness direction at a temperature not lower than the melting point of the fluororesin.
    Type: Application
    Filed: May 26, 2022
    Publication date: September 22, 2022
    Applicants: DAIKIN INDUSTRIES, LTD., FUKUVI CHEMICAL INDUSTRY CO., LTD.
    Inventors: Shinji MURAKAMI, Hirokazu YUKAWA, Keisuke HAGI, Naoaki KANAMORI
  • Publication number: 20220254659
    Abstract: A member for a semiconductor cleaning apparatus, including prepreg containing a carbon fiber and a tetrafluoroethylene/perfluoro(alkyl vinyl ether) copolymer which are thermally fused with each other, wherein the carbon fiber contains a carbon fiber in the form of a sheet.
    Type: Application
    Filed: April 21, 2022
    Publication date: August 11, 2022
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Shinji MURAKAMI, Hirokazu YUKAWA, Keisuke HAGI, Toshiaki MASUI
  • Patent number: 11314190
    Abstract: An imaging system includes a roller that conveys a printing medium, a medium sensor that detects a medium property of the printing medium conveyed by the roller, and a controller that adjusts a conveyance speed of the printing medium by the roller based on the medium property detected by the medium sensor.
    Type: Grant
    Filed: July 1, 2019
    Date of Patent: April 26, 2022
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventors: Yuichiro Tomishima, Hirokazu Yukawa, Sachiyo Yamada
  • Publication number: 20220011093
    Abstract: An optical media sensor includes a guide wall, a light emitter, a light receiver and a blower. The guide wall has an opening. The light emitter emits light to a medium sheet through the opening. The light receiver detects an amount of light travelling from the medium sheet. The blower generates a wind pressure that presses the medium sheet against the guide wall when detecting the amount of light.
    Type: Application
    Filed: January 2, 2020
    Publication date: January 13, 2022
    Applicant: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.
    Inventors: Sachiyo YAMADA, Hirokazu YUKAWA
  • Patent number: 11168210
    Abstract: A resin composition containing a crystalline resin having a melting point of 290° C. or higher, a graphite yarn (A) having a crystallite size in a c-axis direction of not greater than 30.0 ?, and a graphite yarn (B) having a crystallite size in a c-axis direction of greater than 100.0 ?.
    Type: Grant
    Filed: May 15, 2019
    Date of Patent: November 9, 2021
    Assignee: DAIKIN INDUSTRIES, LTD.
    Inventors: Ken Yoshida, Hirokazu Yukawa, Keisuke Hagi
  • Publication number: 20210239609
    Abstract: A water content sensor for a recording medium includes a single light emitting part, a wavelength separation device and a detector device. The single light emitting part emits infrared light in a wavelength range including an absorption wavelength of water along one incident light path toward the recording medium. The wavelength separation device separates infrared light, either reflected from or transmitted through the recording medium, into a first light in a first wavelength range including the absorption wavelength of water and a second light in a second wavelength range excluding the first wavelength range. The detector device receives the first light in the first wavelength range and the second light in the second wavelength range, and generates a first output corresponding to an intensity of the first light received and a second output corresponding to an intensity of the second light received, respectively.
    Type: Application
    Filed: July 26, 2019
    Publication date: August 5, 2021
    Applicant: HEWLETT-PACKARD DEVELOPMENT COMPANY, L.P.
    Inventors: Sachiyo YAMADA, Yuichiro TOMISHIMA, Hirokazu YUKAWA
  • Publication number: 20210223725
    Abstract: An imaging system includes a roller that conveys a printing medium, a medium sensor that detects a medium property of the printing medium conveyed by the roller, and a controller that adjusts a conveyance speed of the printing medium by the roller based on the medium property detected by the medium sensor.
    Type: Application
    Filed: July 1, 2019
    Publication date: July 22, 2021
    Inventors: Yuichiro TOMISHIMA, Hirokazu YUKAWA, Sachiyo YAMADA
  • Publication number: 20210206968
    Abstract: The invention provides a resin composition having a low abrasion coefficient and a low tendency to scratch the surface of an aluminum article when brought into contact with the aluminum article. The resin composition contains a crystalline resin having a melting point of 290° C. or higher, a graphite yarn (A) having a crystallite size in a c-axis direction of not greater than 30.0 ?, and a graphite yarn (B) having a crystallite size in a c-axis direction of greater than 100.0 ?.
    Type: Application
    Filed: May 15, 2019
    Publication date: July 8, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Ken YOSHIDA, Hirokazu YUKAWA, Keisuke HAGI
  • Publication number: 20210206946
    Abstract: A polytetrafluoroethylene composition containing polytetrafluoroethylene and fibrous filler. The fibrous filler has an average fiber length of 100 ?m or shorter and includes fibers having a fiber length of longer than 160 ?m in a proportion of 15% by mass or less.
    Type: Application
    Filed: May 15, 2019
    Publication date: July 8, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Ken YOSHIDA, Keisuke HAGl, Hirokazu YUKAWA
  • Publication number: 20210032379
    Abstract: A method for producing low molecular weight polytetrafluoroethylene which includes: (1) feeding into an airtight container in the absence of oxygen: high molecular weight polytetrafluoroethylene: and a halogenated polymer having a halogen atom other than a fluorine atom; and (2) irradiating the high molecular weight polytetrafluoroethylene to provide low molecular weight polytetrafluoroethylene having a melt viscosity at 380° C. of 1.0×102 to 7.0×105 Pa·s.
    Type: Application
    Filed: February 5, 2019
    Publication date: February 4, 2021
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Masayuki TSUJI, Yuuji TANAKA, Hirokazu YUKAWA
  • Patent number: 8466236
    Abstract: The invention provides a fluororesin composition capable of providing a molded article having low relative dielectric constant, excellent in a temperature stability and causing only small transmission losses. The invention is a fluororesin composition wherein a rate of change in relative dielectric constant between 25° C. and 80° C. of a molded article produced therefrom under a standard condition is not greater than 0.2%.
    Type: Grant
    Filed: February 18, 2008
    Date of Patent: June 18, 2013
    Assignee: Daikin Industries, Ltd.
    Inventors: Hiroyuki Yoshimoto, Hirokazu Yukawa, Yasuhiko Sawada, Taku Yamanaka, Masamichi Sukegawa
  • Publication number: 20100087599
    Abstract: The invention provides a fluororesin composition capable of providing a molded article having low relative dielectric constant, excellent in a temperature stability and causing only small transmission losses. The invention is a fluororesin composition wherein a rate of change in relative dielectric constant between 25° C. and 80° C. of a molded article produced therefrom under a standard condition is not greater than 0.2%.
    Type: Application
    Filed: February 18, 2008
    Publication date: April 8, 2010
    Applicant: DAIKIN INDUSTRIES , LTD.
    Inventors: Hiroyuki Yoshimoto, Hirokazu Yukawa, Yasuhiko Sawada, Taku Yamanaka, Masamichi Sukegawa
  • Patent number: 7528221
    Abstract: It is an object of the present invention to obtain a PTFE molding excellent in flexing resistance without decreasing the tensile strength and tensile elongation. The present invention is a modified polytetrafluoroethylene molded article obtained by molding a modified polytetrafluoroethylene molding powder, wherein the modified polytetrafluoroethylene molding powder is not melt-moldable, the modified polytetrafluoroethylene constituting the modified polytetrafluoroethylene molding powder contains 0.01 to 1% by mass of a perfluorovinyl ether unit represented by the formula (I): (wherein X is a perfluoroalkyl group containing 1 to 6 carbon atoms or a perfluoroalkoxyalkyl group containing 4 to 9 carbon atoms) and the heat of crystallization thereof is 18.0 to 25.0 J/g as measured using a differential scanning calorimeter, and the modified polytetrafluoroethylene molded article has a heat of fusion of not more than 28 J/g and a flex life of at least 200×104 cycles.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: May 5, 2009
    Assignee: Daikin Industries, Ltd.
    Inventors: Tomihiko Yanagiguchi, Shinichi Yano, Masamichi Sukegawa, Hirokazu Yukawa
  • Publication number: 20080227880
    Abstract: The present invention provides a molded porous body with very small air bubbles distributed therein as well as a filter using the porous body. The present invention is related to a porous body comprising a polytetrafluoroethylene-based resin and a thermoplastic resin other than the polytetrafluoroethylene-based resin, and having a specific gravity exceeding 1.80 but less than 2.18 and a percent conversion to crystals of not higher than 50%.
    Type: Application
    Filed: March 13, 2008
    Publication date: September 18, 2008
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Hiroyuki YOSHIMOTO, Hirokazu Yukawa, Yasuhiko Sawada, Taku Yamanaka, Masamichi Sukegawa
  • Publication number: 20080125548
    Abstract: It is an object of the present invention to obtain a PTFE molding excellent in flexing resistance without decreasing the tensile strength and tensile elongation. The present invention is a modified polytetrafluoroethylene molded article obtained by molding a modified polytetrafluoroethylene molding powder, wherein the modified polytetrafluoroethylene molding powder is not melt-moldable, the modified polytetrafluoroethylene constituting the modified polytetrafluoroethylene molding powder contains 0.01 to 1% by mass of a perfluorovinyl ether unit represented by the formula (I): (wherein X is a perfluoroalkyl group containing 1 to 6 carbon atoms or a perfluoroalkoxyalkyl group containing 4 to 9 carbon atoms) and the heat of crystallization thereof is 18.0 to 25.0 J/g as measured using a differential scanning calorimeter, and the modified polytetrafluoroethylene molded article has a heat of fusion of not more than 28 J/g and a flex life of at least 200×104 cycles.
    Type: Application
    Filed: November 30, 2005
    Publication date: May 29, 2008
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Tomihiko Yanagiguchi, Shinichi Yano, Masamichi Sukegawa, Hirokazu Yukawa
  • Patent number: 6197862
    Abstract: Filler-containing polytetrafluoroethylene granular powder, which has a large apparent density, a small average particle size and a sharp particle size distribution and a superior powder flowability, and gives a molded product having a superior tensile strength, elongation and surface roughness, and a process for preparing the same. The granular powder is prepared by granulation of a mixture of a PTFE powder and a filler in water with stirring in the presence of an organic liquid forming liquid-liquid interface with water and a nonionic surfactant.
    Type: Grant
    Filed: March 16, 1998
    Date of Patent: March 6, 2001
    Assignee: Daikin Industries, Ltd.
    Inventors: Michio Asano, Masamichi Sukegawa, Hirokazu Yukawa, Tetsuo Shimizu, Shoji Kawachi, Shingo Tanigawa
  • Patent number: 6037402
    Abstract: Filler-containing polytetrafluoroethylene granular powder, which has a large apparent density, a small average particle size and a narrow particle size distribution and a superior powder flowability, and gives a molded product having a superior tensile strength, elongation and surface roughness, and a process for preparing the same. The granular powder is granulated by mixing, in water, of a PTFE powder and a filler in the state of slurry in the presence of a surfactant and stirring in the presence of an organic liquid forming liquid-liquid interface with water.
    Type: Grant
    Filed: April 24, 1998
    Date of Patent: March 14, 2000
    Assignee: Daikin Industries, Ltd.
    Inventors: Michio Asano, Masamichi Sukegawa, Hirokazu Yukawa, Tetsuo Shimizu, Shoji Kawachi, Shingo Tanigawa, Masayuki Tsuji
  • Patent number: 5763082
    Abstract: Polytetrafluoroethylene molding powder which comprises 0.01 to 1% by weight of a perfluoro(vinyl ether) unit and which has a heat of crystallization of 18.0 to 25.0 J/g. The molding powder provides a molded article which has a flex life of not less than 7 million cycles, a creep resistance (total deformation at 200.degree. C.) of not more than 20%, and a creep resistance (total deformation at 25.degree. C.) of not more than 15%. The polytetrafluoroethylene molding powder which is excellent in both creep resistance and flex fatigue resistance is provided as a molding material for parts which are repeatedly bent such as pump.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: June 9, 1998
    Assignee: Daikin Industries, Ltd.
    Inventors: Masuo Kokumai, Yukiharu Nakamura, Mitsuru Kishine, Tetsuo Kitahaba, Hirokazu Yukawa, Kazuhide Sawada, Sang Bong Han, Tetsuo Shimizu, Takahisa Aoyama
  • Patent number: 5709944
    Abstract: Polytetrafluoroethylene molding powder which comprises 0.01 to 1% by weight of a perfluoro(vinyl ether) unit and which has a heat of crystallization of 18.0 to 25.0 J/g. The molding powder provides a molded article which has a flex life of not less than 7 million cycles, a creep resistance (total deformation at 200.degree. C.) of not more than 20%, and a creep resistance (total deformation at 25.degree. C.) of not more than 15%. The polytetrafluoroethylene molding powder which is excellent in both creep resistance and flex fatigue resistance is provided as a molding material for parts which are repeatedly bent such as pump.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: January 20, 1998
    Assignee: Daikin Industries, Ltd.
    Inventors: Masuo Kokumai, Yukinaru Nakamura, Mitsuru Kishine, Tetsuo Kitahaba, Hirokazu Yukawa, Kazuhide Sawada, Sang Bong Han, Tetsuo Shimizu, Takahisa Aoyama