Patents by Inventor Nobuhiko Tsuda

Nobuhiko Tsuda 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: 8198480
    Abstract: This invention provides a novel compound which can be properly used as a surfactant, a method of producing a fluoropolymer, surfactant and a fluoropolymer aqueous dispersions using the novel compound. This invention is a fluoroalkylcarboxylic acid derivative which is represented by the general formula (i): Rf1(OCH2CF2CF2)n1OCX1X2CF2(Rf2)n2COOM??(i) wherein Rf1 represents a straight or branched fluoroalkyl group containing 1 to 20 carbon atoms, which fluoroalkyl group may optionally contain 1 to 5 oxygen atoms in the principal chain thereof, Rf2 represents a straight or branched fluoroalkylene group containing 1 to 25 carbon atoms, said fluoroalkylene group may optionally contain 1 to 5 oxygen atoms in the principal chain thereof, n1 represents an integer of 0 to 3, n2 represents an integer of 0 or 1, X1 and X2 are the same or different and each represents hydrogen atom or fluorine atom, and M represents NH4 or a monovalent metal element.
    Type: Grant
    Filed: August 6, 2009
    Date of Patent: June 12, 2012
    Assignee: Daikin Industries, Ltd.
    Inventors: Shigeru Morita, Yoshiki Tanaka, Keiko Washino, Nobuhiko Tsuda, Mitsuru Kishine
  • Publication number: 20120123031
    Abstract: The present invention provides an organosol composition that is stable even in the case that the PTFE particle content is high. The present invention relates to an organosol composition of PTFE particles, comprising PTFE particles (A), a polymer (B), and an organic solvent (S), wherein (1) the polymer (B) is soluble in the organic solvent (S), (2) the amount of the PTFE particles (A) is not lower than 50% by mass of the total amount of the PTFE particles (A) and the polymer (B), and (3) the precipitation ratio of the PTFE particles after 48 hours is not higher than 60% when the total solids concentration of the PTFE particles (A) and the polymer (B) is 5% by mass.
    Type: Application
    Filed: May 9, 2011
    Publication date: May 17, 2012
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Takuji Ishikawa, Atsuko Tanaka, Taku Yamanaka, Nobuhiko Tsuda, Kazunobu Uchida, Takahiro Kitahara, Tomoyuki Fukatani
  • Publication number: 20120077915
    Abstract: The present invention provides an aqueous fluororesin dispersion comprising a melt-processable fluororesin which is low in fluorinated surfactant concentration and excellent in dispersion stability even when the concentration of the melt-processable fluororesin is high. The present invention is related to an aqueous fluororesin dispersion comprising a melt-processable fluororesin particle dispersed in an aqueous medium, wherein a concentration of the melt-processable fluororesin is 55 to 75% by mass relative to the aqueous fluororesin dispersion, and a fluorinated surfactant content in the aqueous fluororesin dispersion is not higher than a level corresponding to 100 ppm of the melt-processable fluororesin.
    Type: Application
    Filed: December 8, 2011
    Publication date: March 29, 2012
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Chie SAWAUCHI, Nobuhiko TSUDA
  • Publication number: 20110294945
    Abstract: The present invention provides an aqueous fluoropolymer dispersion having good mechanical characteristics and storage stability and containing substantially no fluorinated surfactant. The present invention is related to an aqueous fluoropolymer dispersion comprising a dispersed fluoropolymer particle with an average primary particle diameter of 50 to 400 nm, a surface layer of the dispersed fluoropolymer particle being obtained by emulsion polymerization of a monomer composition consisting of 99.999 to 98 mole percent of tetrafluoroethylene and 0.001 to 2 mole percent of a modifier monomer, a fluorinated surfactant content being not higher than 50 ppm, a fluoropolymer content being 20 to 75% by mass, and a nonfluorinated nonionic surfactant content being 2 to 15% by mass relative to 100% by mass of the fluoropolymer.
    Type: Application
    Filed: August 8, 2011
    Publication date: December 1, 2011
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Chie SAWAUCHI, Nobuhiko TSUDA
  • Patent number: 8067528
    Abstract: The present invention provides a method of producing a fluoropolymer, wherein polymerization using a carboxylate ester bond-containing carboxylic acid derivative as a surfactant in an aqueous medium to give the fluoropolymer is conducted, the above carboxylate ester bond-containing carboxylic acid derivative has a carboxylate ester bond and —COOM (M representing H, NH4, Li, Na or K), the above carboxylate ester bond may optionally be substituted by fluorine atom.
    Type: Grant
    Filed: May 26, 2010
    Date of Patent: November 29, 2011
    Assignee: Daikin Industries, Ltd.
    Inventors: Nobuhiko Tsuda, Yoshihiro Yamamoto, Yoshinori Nanba, Yasuhiko Sawada, Tetsuo Shimizu
  • Patent number: 7968625
    Abstract: A process for producing an aqueous fluoropolymer dispersion which includes adding a specific compound to a to-be-treated aqueous fluoropolymer dispersion containing a particle of fluoropolymer dispersed therein, the to-be-treated aqueous fluoropolymer dispersion containing a fluorinated surfactant (A) with a molecular weight lower than 1000 in an amount of 100 ppm or less of the fluoropolymer and the specific compound being (1) a sulfosuccinic acid alkyl ester or a salt thereof, or a sulfosuccinic acid fluoroalkyl ester or a salt thereof, (2) the fluorinated surfactant (A), (3) a fluorinated surfactant (B) with a molecular weight lower than 1000, differing from the fluorinated surfactant (A) and/or (4) an aliphatic carboxylic acid or a salt thereof, which compound is added in total amount of 10 to 5000 ppm of said fluoropolymer.
    Type: Grant
    Filed: June 9, 2006
    Date of Patent: June 28, 2011
    Assignee: Daikin Industries, Ltd.
    Inventors: Chie Sawauchi, Nobuhiko Tsuda
  • Patent number: 7968644
    Abstract: The present invention provides a method of producing a fluororesin aqueous dispersion which can produce a fluororesin aqueous dispersion low in fluorine-containing surfactant concentration and high in polytetrafluoroethylene concentration with high efficiency. The invention provides a method of producing a fluororesin aqueous dispersion which comprises subjecting a crude fluororesin aqueous dispersion comprising a polytetrafluoroethylene particle dispersed in an aqueous medium to treatment with an ion-exchange resin and to treatment for concentration by phase separation in the presence of an electrolyte and/or a fluorine-free anionic surfactant.
    Type: Grant
    Filed: June 21, 2007
    Date of Patent: June 28, 2011
    Assignee: Daikin Industries, Ltd.
    Inventors: Chie Sawauchi, Nobuhiko Tsuda
  • Publication number: 20110144255
    Abstract: An object of the present invention is to provide an aqueous fluoropolymer dispersion inhibited from viscosity rising and excellent in mechanical stability in spite of a low fluorinated surfactant concentration. The invention provides an aqueous fluoropolymer dispersion comprising particles of a fluoropolymer as dispersed in an aqueous medium wherein a fluorinated surfactant (A) having a molecular weight lower than 1000 amounts to not higher than 100 ppm of the mass of the fluoropolymer, the aqueous fluoropolymer dispersion containing an anionic surfactant (B) other than the fluorinated surfactant (A) as well as a water-soluble polymer (C).
    Type: Application
    Filed: February 24, 2011
    Publication date: June 16, 2011
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Chie SAWAUCHI, Nobuhiko TSUDA, Wade Martin SIMPSON
  • Publication number: 20100234635
    Abstract: The present invention provides a method of producing a fluoropolymer, wherein polymerization using a carboxylate ester bond-containing carboxylic acid derivative as a surfactant in an aqueous medium to give the fluoropolymer is conducted, the above carboxylate ester bond-containing carboxylic acid derivative has a carboxylate ester bond and —COOM (M representing H, NH4, Li, Na or K), the above carboxylate ester bond may optionally be substituted by fluorine atom.
    Type: Application
    Filed: May 26, 2010
    Publication date: September 16, 2010
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Nobuhiko TSUDA, Yoshihiro YAMAMOTO, Yoshinori NANBA, Yasuhiko SAWADA, Tetsuo SHIMIZU
  • Publication number: 20100222491
    Abstract: The present invention has an object to provide an aqueous fluoropolymer dispersion which is excellently prevented from foaming without significant impairment in viscosity and in mechanical stability. The present invention is related to an aqueous fluoropolymer dispersion comprising a particle of fluoropolymer as dispersed in an aqueous medium in the presence of a specific nonionic surfactant, wherein the specific nonionic surfactant comprises a compound having an average total hydrophilic group content of 45 to 90% by mass, each hydrocarbon group in the compound constituting the specific nonionic surfactant is only a hydrocarbon group of 1 to 5 consecutively neighboring carbon atoms, and the fluorinated surfactant in the aqueous fluoropolymer dispersion amounts to 500 ppm or less of the solid matter of the fluoropolymer.
    Type: Application
    Filed: December 28, 2006
    Publication date: September 2, 2010
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Chie Sawauchi, Nobuhiko Tsuda, Toshirou Miura
  • Patent number: 7777075
    Abstract: The invention provides a fluoroethercarboxylic acid which is represented by the general formula (I): Rf1OCHFCF2ORf2COOM??(I) wherein Rf1 represents a partially or fully fluorinated alkyl group, which may optionally be interrupted with one or more oxygen atoms, Rf2 represents a partially or fully fluorinated alkylene group, which may optionally be interrupted with one or more oxygen atoms, and M represents a monovalent alkali metal, NH4 or H. The fluoroethercarboxylic acid can be suitably used as a surfactant and is low in bioaccumulation. The invention is also a method of fluoropolymer production and an aqueous fluoropolymer dispersion, using the fluoroethercarboxylic acid as a surfactant.
    Type: Grant
    Filed: January 2, 2009
    Date of Patent: August 17, 2010
    Assignee: Daikin Industries, Ltd.
    Inventors: Takuji Ishikawa, Nobuhiko Tsuda, Yoshihiro Yamamoto
  • Publication number: 20100204345
    Abstract: The present invention provides an aqueous dispersion of a low-molecular-weight polytetrafluoroethylene (PTFE), which contains an easily removable surfactant, and has a good dispersion stability. Specifically, the present invention provides an aqueous dispersion of a low-molecular-weight PTFE comprising tetrafluoroethylene (TFE) units, or TFE units and modifying monomer units which are copolymerizable with the TFE units, wherein the aqueous dispersion contains from 70 to 9,000 ppm, based on the aqueous dispersion, of a fluorine-containing compound of the formula (1) below: X—(CF2)m—Y??(1) where X is H or F; m is an integer from 3 to 5; and Y is —SO3M, —SO4M, —SO3R, —SO4R, —COOM, —PO3M2 or —PO4M2, M being H, NH4 or an alkali metal, and R being an alkyl group having 1 to 12 carbons, and the low-molecular-weight PTFE has an average primary particle size of from 100 to 350 nm.
    Type: Application
    Filed: August 7, 2008
    Publication date: August 12, 2010
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Taku Yamanaka, Nobuhiko Tsuda, Masayuki Tsuji, Yasuhiko Sawada
  • Publication number: 20100197852
    Abstract: The invention provides a compound which is useful in production of a fluoropolymer and easy to be removed from the produced fluoropolymer, a method of producing the compound, and a method of producing a fluoropolymer using the compound. The invention provides a compound which is represented by Rf1—CH2O—CF2—CHF—Rf2—X, wherein Rf1 represents a fluoroalkyl group containing 1 to 5 carbon atoms, Rf2 represents a fluoroalkylene group containing 1 to 3 carbon atoms, X represents —COOM or —SO3M, and M represents one of H, K, Na, and NH4.
    Type: Application
    Filed: July 24, 2008
    Publication date: August 5, 2010
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Nobuhiko Tsuda, Akinari Sugiyama
  • Patent number: 7754796
    Abstract: The present invention provides a method of producing a fluoropolymer, wherein polymerization using a carboxylate ester bond-containing carboxylic acid derivative as a surfactant in an aqueous medium to give the fluoropolymer is conducted, the above carboxylate ester bond-containing carboxylic acid derivative has a carboxylate ester bond and —COOM (M representing H, NH4, Li, Na or K), the above carboxylate ester bond may optionally be substituted by fluorine atom.
    Type: Grant
    Filed: June 29, 2009
    Date of Patent: July 13, 2010
    Assignee: Daikin Industries, Ltd.
    Inventors: Nobuhiko Tsuda, Yoshihiro Yamamoto, Yoshinori Nanba, Yasuhiko Sawada, Tetsuo Shimizu
  • Publication number: 20100168301
    Abstract: It is an object of the present invention to provide an aqueous fluoropolymer dispersion which will not send out any amine-like odor in spite of its having been brought into contact with an anion exchange resin as well as a method of producing the same. This invention is related to an aqueous fluoropolymer dispersion containing a nitrogen-containing organic base and/or a salt thereof, together with a particle of fluoropolymer dispersed therein wherein said nitrogen-containing organic base and/or the salt thereof amounts, in total, to 0 to 1 ppm of said aqueous fluoropolymer dispersion.
    Type: Application
    Filed: June 23, 2006
    Publication date: July 1, 2010
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Chie Sawauchi, Nobuhiko Tsuda
  • Patent number: 7714047
    Abstract: The present invention provides a method of producing a fluoropolymer aqueous dispersion by which the fluorine-containing emulsifier contained in the fluoropolymer aqueous dispersion as obtained after polymerization can be efficiently removed as well as a fluoropolymer aqueous dispersion low in fluorine-containing emulsifier concentration. The present invention is a method of producing a fluoropolymer aqueous dispersion which comprises carrying out a concentration treatment comprising a concentration operation of a pretreatment fluoropolymer aqueous dispersion, wherein the pretreatment fluoropolymer aqueous dispersion is obtained by carrying out a polymerization in an aqueous medium in the presence of a fluorine-containing surfactant (A), the fluorine-containing surfactant (A) is a fluorine-containing surfactant having an octanol/water partition coefficient of 1.5 to 3.5.
    Type: Grant
    Filed: June 1, 2009
    Date of Patent: May 11, 2010
    Assignee: Daikin Industries, Ltd.
    Inventors: Nobuhiko Tsuda, Chie Sawauchi, Yasuhiko Sawada, Tetsuo Shimizu
  • Patent number: 7696268
    Abstract: The present invention provides a method of producing a fluoropolymer aqueous dispersion by which the fluorine-containing emulsifier contained in the fluoropolymer aqueous dispersion as obtained after polymerization can be efficiently removed as well as a fluoropolymer aqueous dispersion low in fluorine-containing emulsifier concentration. The present invention is a method of producing a fluoropolymer aqueous dispersion which comprises carrying out a concentration treatment comprising a concentration operation of a pretreatment fluoropolymer aqueous dispersion, wherein the pretreatment fluoropolymer aqueous dispersion is obtained by carrying out a polymerization in an aqueous medium in the presence of a fluorine-containing surfactant (A), the fluorine-containing surfactant (A) is a fluorine-containing surfactant having an octanol/water partition coefficient of 1.5 to 3.5.
    Type: Grant
    Filed: October 29, 2004
    Date of Patent: April 13, 2010
    Assignee: Daikin Industries, Ltd.
    Inventors: Nobuhiko Tsuda, Chie Sawauchi, Yasuhiko Sawada, Tetsuo Shimizu
  • Publication number: 20090312443
    Abstract: The present invention provides a method of obtaining good aqueous fluoropolymer dispersions low in fluorinated surfactant content by efficiently removing the fluorinated surfactant through pH adjustment. The present invention is related to a method of producing an aqueous fluoropolymer dispersion comprising a contact treatment for brining a raw aqueous fluoropolymer dispersion into contact with an anion exchanger, and the contact treatment being carried out while a pH of the raw aqueous fluoropolymer dispersion is adjusted to 2 to 9.
    Type: Application
    Filed: July 6, 2007
    Publication date: December 17, 2009
    Inventors: Chie Sawauchi, Nobuhiko Tsuda
  • Publication number: 20090298984
    Abstract: This invention provides a novel compound which can be properly used as a surfactant, a method of producing a fluoropolymer, surfactant and a fluoropolymer aqueous dispersions using the novel compound. This invention is a fluoroalkylcarboxylic acid derivative which is represented by the general formula (i): Rf1(OCH2CF2CF2)n1OCX1X2CF2(Rf2)n2COOM??(i) wherein Rf1 represents a straight or branched fluoroalkyl group containing 1 to 20 carbon atoms, which fluoroalkyl group may optionally contain 1 to 5 oxygen atoms in the principal chain thereof, Rf2 represents a straight or branched fluoroalkylene group containing 1 to 25 carbon atoms, said fluoroalkylene group may optionally contain 1 to 5 oxygen atoms in the principal chain thereof, n1 represents an integer of 0 to 3, n2 represents an integer of 0 or 1, X1 and X2 are the same or different and each represents hydrogen atom or fluorine atom, and M represents NH4 or a monovalent metal element.
    Type: Application
    Filed: August 6, 2009
    Publication date: December 3, 2009
    Applicant: DAIKIN INDUSTRIES, LTD.
    Inventors: Shigeru MORITA, Yoshiki TANAKA, Keiko WASHINO, Nobuhiko TSUDA, Mitsuru KISHINE
  • Publication number: 20090286932
    Abstract: The present invention provides an aqueous fluoropolymer dispersion having good mechanical characteristics and storage stability and containing substantially no fluorinated surfactant. The present invention is related to an aqueous fluoropolymer dispersion comprising a dispersed fluoropolymer particle with an average primary particle diameter of 50 to 400 nm, a surface layer of the dispersed fluoropolymer particle being obtained by emulsion polymerization of a monomer composition consisting of 99.999 to 98 mole percent of tetrafluoroethylene and 0.001 to 2 mole percent of a modifier monomer, a fluorinated surfactant content being not higher than 50 ppm, a fluoropolymer content being 20 to 75% by mass, and a nonfluorinated nonionic surfactant content being 2 to 15% by mass relative to 100% by mass of the fluoropolymer.
    Type: Application
    Filed: July 5, 2007
    Publication date: November 19, 2009
    Applicant: Daikin Industries, LTD.
    Inventors: Chie Sawauchi, Nobuhiko Tsuda