Patents by Inventor Hirokazu Aoyama

Hirokazu Aoyama 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: 6610896
    Abstract: A process for preparing a perfluoroalkadiene compound of formula (I) CF2═CF—(CF2)n-4—CF═CF2  (I) (wherein n is an integer from 4 to 20) by the deiodofluorination of a compound of formula (II) I—(CF2)n—I  (II) (wherein n is as defined above), characterised in that said deiodofluorination is conducted in the presence of metallic zinc and a nitrogen-containing organic compound.
    Type: Grant
    Filed: July 5, 2002
    Date of Patent: August 26, 2003
    Assignee: Daikin Industries, Ltd.
    Inventors: Jun Miki, Hitoshi Yoshimi, Hirokazu Aoyama
  • Publication number: 20030152864
    Abstract: There is provided a novel fluorine-containing polymer having an acid-reactive group which has a high transparency against energy rays (radioactive rays) in a vacuum ultraviolet region (157 nm), and further there are provided a material for fluorine-containing base polymer prepared from the polymer and suitable for a photoresist and a chemically amplifying type resist composition obtained therefrom.
    Type: Application
    Filed: October 3, 2002
    Publication date: August 14, 2003
    Applicant: Daikin Industries, Ltd.
    Inventors: Takayuki Araki, Meiten Koh, Yoshito Tanaka, Takuji Ishikawa, Hirokazu Aoyama, Tetsuo Shimizu
  • Publication number: 20030144557
    Abstract: The present invention provides a process for producing a linear perfluoroalkanone or a perfluorocycloalkanone, which comprises using as a starting material a combination of the same or different kinds of compounds that are selected from perfluoroalkanoyl halides represented by the formula: F(CF2)nCOX wherein X is F, Cl, Br or I and n is an integer of 1 to 8, or a perfluoroalkanedioyl dihalide represented by the formula: XOC(CF2)nCOX wherein X is F, Cl, Br or I and n is an integer of 3 to 8, and reacting the starting material with a metal carbonate or metal carbonates. According to the present invention, perfluoroalkanones can be produced with a good yield from relatively easily available starting materials by a simple synthesis method.
    Type: Application
    Filed: October 18, 2002
    Publication date: July 31, 2003
    Inventors: Kouzou Noda, Hirokazu Aoyama
  • Publication number: 20020193643
    Abstract: A process for preparing a perfluoroalkadiene compound of formula (I)
    Type: Application
    Filed: July 5, 2002
    Publication date: December 19, 2002
    Inventors: Jun Miki, Hitoshi Yoshimi, Hirokazu Aoyama
  • Patent number: 6380148
    Abstract: The present invention provides a method for isolating and purifying 1,1,1,2,2-pentafluoroethyl iodide or hydrogen fluoride from a mixture of 1,1,1,2,2-pentafluoroethyl iodide and hydrogen fluoride, characterized by distilling an azeotropic mixture of 1,1,1,2,2-pentafluoroethyl iodide and hydrogen fluoride from a mixture containing 1,1,1,2,2-pentafluoroethyl iodide and hydrogen fluoride either after liquid—liquid separation when the mixture is heterogeneous or directly when the mixture is homogeneous to obtain 1,1,1,2,2-pentafluoroethyl iodide or hydrogen fluoride from the bottom of the distillation column.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: April 30, 2002
    Assignee: Daikin Industries
    Inventors: Eiji Seki, Tatsuya Otsuka, Tatsuya Hirata, Yoshinori Tanaka, Hirokazu Aoyama
  • Patent number: 6291728
    Abstract: A manufacturing method for 1,1,1,3,3-pentafluoropropane, wherein 1,1,1,3,3-pentafluoropropane (HFC-245fa) is obtained by reacting halogenated propane, for example, 1,1,1,3,3-pentachloropropane and so on, which is represented by the general formula: CX3CH2CHX2 [In the general formula, X is fluorine atom (F) or chlorine atom (Cl), and all of X can not be fluorine atoms at the same time], with anhydrous hydrofluoric acid (HF) under the presence of antimony catalyst. HFC-245fa can be obtained with high yield and economical advantages through simple process.
    Type: Grant
    Filed: March 27, 1998
    Date of Patent: September 18, 2001
    Assignee: Daikin Industries, Ltd.
    Inventors: Hirokazu Aoyama, Tatsuo Nakada, Akinori Yamamoto
  • Patent number: 6271189
    Abstract: The present invention provides a method for isolating and purifying 1,1,1,2,2-pentafluoroethyl iodide or hydrogen fluoride from a mixture of 1,1,1,2,2-pentafluoroethyl iodide and hydrogen fluoride, characterized by distilling an azeotropic mixture of 1,1,1,2,2-pentafluoroethyl iodide and hydrogen fluoride from a mixture containing 1,1,1,2,2-pentafluoroethyl iodide and hydrogen fluoride either after liquid-liquid separation when the mixture is heterogeneous or directly when the mixture is homogeneous to obtain 1,1,1,2,2-pentafluoroethyl iodide or hydrogen fluoride from the bottom of the distillation column.
    Type: Grant
    Filed: December 13, 1999
    Date of Patent: August 7, 2001
    Assignee: Daikin Industries, Ltd.
    Inventors: Eiji Seki, Tatsuya Otsuka, Tatsuya Hirata, Yoshinori Tanaka, Hirokazu Aoyama
  • Patent number: 6255524
    Abstract: An acid chloride can be produced at a high yield from a primary alcohol having a polyfluoroalkyl group and one methylene group by (1) a method in which RfCH2OH (wherein Rf is a polyfluoroalkyl group) is reacted with chlorine to produce RfCOCl, (2) a method in which RfCHO is reacted with chlorine to produce RfCOCl, and (3) a method for producing an acid chloride comprising (a) a step in which an aldehyde (RfCHO) is formed from an alcohol (RfCH2OH), (b) a step in which a monochloroester (RfCOOCHClRf) is formed from the aldehyde and an acid chloride (RfCOCl), and (c) a step in which the acid chloride (RfCOCl) is formed from the monochloroester.
    Type: Grant
    Filed: June 25, 1999
    Date of Patent: July 3, 2001
    Assignee: Daikin Industries Ltd.
    Inventors: Hirokazu Aoyama, Shoji Takagi, Shinichi Matsumura, Yoshinori Tanaka
  • Patent number: 6242410
    Abstract: There is provided an azeotropic mixture consisting substantially of a hexafluoropropylene dimer and acetonitrile. In addition, there is provided a process for the separation of a hexafluoropropylene dimer which does not substantially contain acetonitrile, or acetonitrile which does not substantially contain a hexafluoropropylene dimer from a mixture which contains acetonitrile and the hexafluoropropylene dimer, comprising the steps of subjecting the mixture to a distillation operation and distilling off the azeotropic mixture which consists substantially of the hexafluoropropylene dimer and acetonitrile.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: June 5, 2001
    Assignee: Daikin Industries, Ltd.
    Inventors: Hirokazu Aoyama, Akikazu Tabuchi
  • Patent number: 6239319
    Abstract: The present invention provides a new industrial process for producing perfluoroalkanes in order to overcome the problems of processes for producing perfluoroalkanes in the prior art. The process of the present invention is a process for producing a perfluoroalkane corresponding to a general formula Rf-F (wherein Rf- is a perfluoroalkyl group represented by F(CF2)n— and n is an integer of 2 to 10) by contacting a perfluoroalkyl iodide with gaseous fluorine to cause a reaction therebetween, wherein the contact is made in the presence of the liquid compound which is at least one liquid which is substantially inert to the perfluoroalkyl iodide and gaseous fluorine under the condition of the process and which is selected from a perfluoro-compound, a chlorofluoro-compound, and hydrogen fluoride.
    Type: Grant
    Filed: August 23, 1999
    Date of Patent: May 29, 2001
    Assignee: Daikin Industries Ltd.
    Inventors: Tatsuya Otsuka, Tatsuya Hirata, Kyohiro Kan, Hirokazu Aoyama
  • Patent number: 6191326
    Abstract: This invention provides a process for preparing 1,1,1,2,3,3,3-heptafluoropropane, which comprises reacting 2-trifluoromethyl-3,3,3-trifluoropropionic acid with fluorine gas. The process according to this invention produces 1,1,1,2,3,3,3-heptafluoropropane with high selectivity and is an industrially efficient and economical method.
    Type: Grant
    Filed: September 3, 1999
    Date of Patent: February 20, 2001
    Assignee: Daikin Industries, Inc.
    Inventors: Tatsuya Otsuka, Hirokazu Aoyama
  • Patent number: 6060628
    Abstract: A manufacturing method for 1,1,1,3,3-pentafluoropropane in which the method is composed of:step A wherein 2,3-dichloro-1,1,1,3,3-pentafluoropropane is reduced with hydrogen under the presence of hydrogenation catalyst in gaseous phase;step B wherein all of the products of the said step A are introduced into a cooler condenser, so that either a component of hydrogen and hydrogen chloride as non-condensation component and another compoment of 1,1,1,3,3-pentafluoropropane as condensation components or a component of hydrogen as non-condensation component and another component of hydrogen chloride and 1,1,1,3,3-pentafluoropropane as condensation component are obtained;step C wherein hydrogen is separated from the non-condensation component of the said step B, and it is recycled to the said step A; andstep D wherein 1,1,1,3,3-pentafluoropropane is separated from the condensation component of the said step B.
    Type: Grant
    Filed: August 26, 1997
    Date of Patent: May 9, 2000
    Assignee: Daikin Industries Ltd.
    Inventors: Hirokazu Aoyama, Noriaki Shibata, Akinori Yamamoto
  • Patent number: 6018084
    Abstract: A manufacturing method for 1,1,1,3,3-pentafluoropropane comprises a first process, in which 1,1,1-trifluoro-3-chloro-2-propene is obtained by inducing a reaction between 1,1,1,3,3-pentafluoropropane and hydrogen fluoride in the vapor phase, and a second process, in which the 1,1,1,3,3-pentafluoropropane is obtained by inducing a reaction between 1,1,1-trifluoro-3-chloro-2-propene and hydrogen in the vapor phase, and 1,1,1-trifluoro-3-chloro-2-propene obtained in the first process is supplied to the second process after removing the HCl by-products. This invention can provide a new economic manufacturing method of 1,1,1,3,3-pentafluoropropane with high yield and selectivity.
    Type: Grant
    Filed: June 25, 1998
    Date of Patent: January 25, 2000
    Assignee: Daikin Industries Ltd.
    Inventors: Tatsuo Nakada, Hirokazu Aoyama, Akinori Yamamoto
  • Patent number: 5965779
    Abstract: The present invention provides processes for preparing 2,2,3,3,4-pentafluorooxetane and/or 2,2,3,3,4,4-hexafluorooxetane which comprises reacting 2,2,3,3-tetrafluorooxetane with fluorine gas, the process inhibiting decomposition of the oxetane ring during the reaction and producing a reduced amount of by-products.
    Type: Grant
    Filed: February 20, 1998
    Date of Patent: October 12, 1999
    Assignee: Daikin Industries, Ltd.
    Inventors: Tatsuya Otsuka, Hirokazu Aoyama
  • Patent number: 5945562
    Abstract: A process of preparing a perfluoroalkylcarboxylic acid by an oxidative decomposition reaction of a perfluoroalkylethylene corresponding to a general formula:Rf--CH.dbd.CH.sub.2?wherein, Rf is a perfluoroalkyl group containing 2 to 14 carbon atoms.!to obtain a perfluoroalkylcarboxylic acid corresponding to a general formula:Rf--COOH?wherein, Rf is the same as the above.!characterized that the reaction is carried out in the presence of an organic solvent which is compatible with water and substantially inert to the above reaction, a ruthenium compound as a catalyst and an aqueous solution of at least one of hypochlorous acid or a salt thereof is provided.
    Type: Grant
    Filed: January 27, 1998
    Date of Patent: August 31, 1999
    Assignee: Daikin Industries Ltd.
    Inventors: Hirokazu Aoyama, Yasumichi Chiba
  • Patent number: 5919993
    Abstract: At least one halogenated compound selected from the group consisting of 1,1,1,4,4,4-hexafluoro-2,3-dichlorobutane, 1,1,1,4,4,4-hexafluoro-2-chloro-2-butene, 1,1,1,2,4,4,4-heptafluoro-2-butene and 1,1,1,2,2,4,4,4-octafluorobutane, is prepared by reacting 1,1,2,3,4,4-hexachloro-1,3-butadiene with hydrogen fluoride in a gas phase in the presence of a fluorinating catalyst. Desired products can be prepared commercially according to the present invention.
    Type: Grant
    Filed: September 3, 1993
    Date of Patent: July 6, 1999
    Assignee: Daikin Industries Ltd.
    Inventors: Tatsuo Nakada, Hirokazu Aoyama, Satoshi Koyama
  • Patent number: 5821392
    Abstract: A manufacturing method for 1,1,1,3,3-pentafluoropropane by reducing 2,3-dichloro-1,1,1,3,3-pentafluoropropane as a raw material with hydrogen under the presence of a catalyst in a gaseous phase to produce 1,1,1,3,3-pentafluoropropane where a hydrogenation catalyst is used composed of palladium and at least one kind of additional metal selected from the group of silver, gold, copper, zinc, rhenium, cobalt, nickel, iridium, ruthenium, rhodium, tantalum, niobium, molybdenum, osmium and tungsten.
    Type: Grant
    Filed: August 11, 1997
    Date of Patent: October 13, 1998
    Assignee: Daikin Industries Ltd.
    Inventors: Hirokazu Aoyama, Akinori Yamamoto, Noriaki Shibata
  • Patent number: 5789632
    Abstract: A mixture containing hydrogen fluoride and 1,1,1,3,3-pentafluoro-2,3-dichloropropane is subjected to distillation to form an azeotropic composition of 85 to 95 mol % of hydrogen fluoride and 15 to 5 mol % of 1,1,1,3,3-pentafluoro-2,3-dichloropropane, and the azeotropic composition is liquid-separated to form a lower liquid phase. Then, an azeotropic composition is withdrawn from the lower liquid phase by distillation, whereby 1,1,1,3,3-pentafluoro-2,3-dichloropropane is obtained.Without formation of an aqueous solution of diluted hydrofluoric acid, 1,1,1,3,3-pentafluoro-2,3-dichloropropane is obtained which is substantially free of hydrogen fluoride.
    Type: Grant
    Filed: June 20, 1996
    Date of Patent: August 4, 1998
    Assignee: Daikin Industries, Ltd.
    Inventors: Tatsuo Nakada, Hirokazu Aoyama
  • Patent number: 5773404
    Abstract: To provide an azeotropic composition comprising cis-1,1,2,2,3,4-hexafluorocyclobutane and at least one compound selected from the group consisting of methanol, ethanol, isopropanol, n-propanol, tert-butanol, cyclopentane, n-octane, isooctane, n-heptane and methylcyclohexane, and a detergent, drying agent and foaming agent, which use the above-mentioned azeotropic composition. The azeotropic composition of the present invention is an alternative fleon composition having less influence on plastics, being excellent in solvency and having less influence on the ozone layer.
    Type: Grant
    Filed: October 11, 1996
    Date of Patent: June 30, 1998
    Assignee: Daikin Industries, Ltd.
    Inventors: Hirokazu Aoyama, Satoshi Ide, Akinori Yamamoto
  • Patent number: 5763703
    Abstract: Manufacturing method for hexafluorocyclobutene in which 1,2-dichlorohexafluorocyclobutane is dechlorinated using hydrogen in the presence of a metal oxide and/or silicon oxide catalyst. Manufacturing method for (Z)-1,2,3,3,4,4-hexafluorocyclobutane which carries out the hydrogen-adding reaction (hydrogen reduction) of the raw material, 1,2-dichlorohexafluorocyclobutane, in the presence of a rhodium catalyst, or which carries out vapor-phase hydrogen reduction of hexafluorocyclobutene in the presence of a palladium catalyst.Using this manufacturing method, hexafluorocyclobutene can easily be derived in a single step with high selectivity from 1,2-dichlorohexafluorocyclobutane which can be obtained readily and at a low cost. This method also produces a high yield of (Z)-1,2,3,3,4,4-hexafluorocyclobutane.
    Type: Grant
    Filed: February 26, 1996
    Date of Patent: June 9, 1998
    Assignee: Daikin Industries Ltd.
    Inventors: Tatsuo Nakada, Hirokazu Aoyama, Akinori Yamamoto