Patents by Inventor Takashi Tohzuka

Takashi Tohzuka 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: 5227516
    Abstract: A fluorine-containing polyether of the formula:R.sub.f --X--A (I)orA--X--R'.sub.f --X--A (II)wherein R.sub.f and R'.sub.f are each a linear group containing a perfluoroalkyl polyether group, X is --CF.sub.2 COO--, --C.sub.2 F.sub.4 COO-- or --CF.sub.2 CF.sub.2 -- and A is a group containing a polyalkylene glycol group. The polyether can be used as a nonionic surfactant which is compatible with a perfluoroalkyl polyether.
    Type: Grant
    Filed: December 18, 1991
    Date of Patent: July 13, 1993
    Assignee: Daikin Industries Ltd.
    Inventors: Takashi Tohzuka, Sueyoshi Ishikawa, Ikuo Yamamoto
  • Patent number: 5214216
    Abstract: A fluorine-containing polyether of the formula:R.sub.f --X--A (I)orA--X--R'.sub.f --X--A (II)wherein R.sub.f and R'.sub.f are each a linear group containing a perfluoroalkyl polyether group, X is --CF.sub.2 COO--, --C.sub.2 F.sub.4 COO-- or --CF.sub.2 CF.sub.2 -- and A is a group containing a polyalkylene glycol group. The polyether can be used as a nonionic surfactant which is compatible with a perfluoroalkyl polyether.
    Type: Grant
    Filed: July 24, 1990
    Date of Patent: May 25, 1993
    Assignee: Daikin Industries Ltd.
    Inventors: Takashi Tohzuka, Sueyoshi Ishikawa, Ikuo Yamamoto
  • Patent number: 5132446
    Abstract: A fluorine-containing phosphate ester of the formula: ##STR1## wherein R.sub.f is a group containing a perfluoroalkyl polyether group of the formula:F(CF.sub.2 CF.sub.2 CF.sub.2 O).sub.m CF.sub.2 CF.sub.2 --wherein m is 2 to 200, and n is an integer of 1 to 3 is used as a rust preventive which can be homogeneously mixed with a fluorine-containing grease.
    Type: Grant
    Filed: October 25, 1990
    Date of Patent: July 21, 1992
    Assignee: Daikin Industries, Ltd.
    Inventors: Takashi Tohzuka, Yoshiaki Kataoka, Sueyoshi Ishikawa
  • Patent number: 5004554
    Abstract: A fluorine-containing polyether of the formula:R.sub.f.sup.1 CF.sub.2 CF.sub.2 COOR.sub.f.sup.2 (I)orR.sub.f.sup.2 OCO--CF.sub.2 CF.sub.2 R'.sub.f.sup.1 CF.sub.2 CF.sub.2 --COOR.sub.f.sup.2 (II)wherein R.sub.f.sup.1 and R'.sub.f.sup.1 are each a group containing a perfluoroalkyl polyether group, and R.sub.f.sup.2 is a fluorine-containing alkyl group or a fluorine-containing ether group, can be used as a lubricant which has good properties such as lubricity and durability properties.
    Type: Grant
    Filed: July 24, 1990
    Date of Patent: April 2, 1991
    Assignee: Daikin Industries Ltd.
    Inventors: Takashi Tohzuka, Ikuo Yamamoto, Yoshihiko Misugi
  • Patent number: 4985161
    Abstract: A fluorine-containing grease comprising polytetrafluoroethylene and a perfluoroalkyl polyether which is prepared by polymerizing tetrafluoroethylene in the perfluoroalkyl polyether has good homogeneity and lubricity.
    Type: Grant
    Filed: May 17, 1990
    Date of Patent: January 15, 1991
    Assignee: Daikin Industries Ltd.
    Inventors: Takashi Tohzuka, Yoshiaki Kataoka, Sueyoshi Ishikawa, Koji Fujiwara
  • Patent number: 4973762
    Abstract: A polyfluoroiodide is produced by reacting an acid halide of a polyfluorocarbon in a perhalogenated solvent with I.sub.2 and at least one salt selected from the group consisting of an alkali metal carbonate and an alkaline earth metal carbonate.
    Type: Grant
    Filed: June 27, 1989
    Date of Patent: November 27, 1990
    Assignee: Daikin Industries Ltd.
    Inventors: Takashi Tohzuka, Koji Fujiwara
  • Patent number: 4973742
    Abstract: A halogen-containing polyether comprising repeating units of the formula:--(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.a --(CHClCF.sub.2 CF.sub.2 O).sub.b --(CCl.sub.2 CF.sub.2 CF.sub.2 O).sub.c --(CHFCF.sub.2 CF.sub.2 O).sub.d --(CFClCF.sub.2 CF.sub.2 O).sub.e --(CF.sub.2 CF.sub.2 CF.sub.2 O).sub.f --(I)wherein a, b, c, d, e and f are each an integer not less than 0 and satisfy the following equations:2.ltoreq.a+b+c+d+e+f.ltoreq.200and1.ltoreq.a+c+d+f,which may be prepared by ring-opening polymerizing 2,2,3,3-tetrafluorooxetane in the presence of a polymerization initiator to give a polyether comprising repeating units of the formula:--(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.a -- (II)wherein a is the same as defined above, and optionally fluorinating and/or chlorinating the polyether (II).
    Type: Grant
    Filed: April 14, 1989
    Date of Patent: November 27, 1990
    Assignee: Daikin Industries Ltd.
    Inventors: Yohnosuke Ohsaka, Takashi Tohzuka, Shoji Takaki
  • Patent number: 4904417
    Abstract: A fluorine-containing polyether of the formula:A--X--A'wherein A and A' are the same or different and are each --COF, --COCl or --COOH, and X is --CF.sub.2 CF.sub.2 --R.sub.f --O--C.sub.m F.sub.2m --O--R.sub.f 'CF.sub.2 CF.sub.2 -- in which R.sub.f and R.sub.f ' are the same or different and are each a group containing a perfluoroalkylpolyether group, and m is a number of from 1 to 6, and a fluorine-containing polyether of the formula:Z--X.sub.n --Z'wherein X is the same as defined above, Z and Z' are the same or different and are each --COF, --COCl, --COOH or --CF.sub.2 CF.sub.2 --R.sub.f --B in which R.sub.f is the same as defined above and B is a fluorine atom or a C.sub.1 -C.sub.5 perfluoroalkyl group, and n is a number of from 0 to 100 provided that when n is 1, Z and Z' are each --CF.sub.2 CF.sub.2 R.sub.f B, provided that when n is 0, both Z and Z' are each --CF.sub.2 CF.sub.2 R.sub.f B or when n is 1, at least one of Z and Z' is --CF.sub.2 CF.sub.2 R.sub.f B.
    Type: Grant
    Filed: June 1, 1988
    Date of Patent: February 27, 1990
    Assignee: Daikin Industries Ltd.
    Inventors: Yohnosuke Ohsaka, Takashi Tohzuka, Yoshitaka Honda, Norio Yanagisawa
  • Patent number: 4845268
    Abstract: A halogen-containing polyether comprising repeating units of the formula:--(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.2 --(CHClCF.sub.2 CF.sub.2 O).sub.b --(CCl.sub.2 CF.sub.2 CF.sub.2 O).sub.c --(CHFCF.sub.2 CF.sub.2 O).sub.d --(CFClCF.sub.2 CF.sub.2 O).sub.e --(CF.sub.2 CF.sub.2 CF.sub.2 O).sub.f --(I)wherein a, b, c, d, e and f are each an integer not less than 0 and satisfy the following equations:2.ltoreq.a+b+c+d+e+f.ltoreq.200and1.ltoreq.a+c+d+f,which may be prepared by ring-opening polymerizing 2,2,3,3-tetrafluorooxetane in the presence of an polymerization initiator to give a polyether comprising repeating units of the formula:--(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.a -- (II)wherein a is the same as defined above, and optionally fluorinating and/or chlorinating the polyether (II).
    Type: Grant
    Filed: December 9, 1986
    Date of Patent: July 4, 1989
    Assignee: Daikin Industries, Ltd.
    Inventors: Yohnosuke Ohsaka, Takashi Tohzuka, Shoji Takaki
  • Patent number: 4836944
    Abstract: A halogen-containing polyether which comprises a repeating unit structure of the formula:--(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.a --(CHClCF.sub.2 CF.sub.2 O).sub.b --(CCl.sub.2 CF.sub.2 CF.sub.2 O).sub.c --(CHFCF.sub.2 CF.sub.2 O).sub.d --(CFClCF.sub.2 CF.sub.2 O).sub.e --(CF.sub.2 CF.sub.2 CF.sub.2 O).sub.f --(I)wherein a, b, c, d, e and f are each 0 or a positive integer and satisfy the following equations:2.ltoreq.a+b+c+d+e+f.ltoreq.200 and 1.ltoreq.a+c+d+fand at least one terminal group selected from the group consisting of groups represented by the formulas:--CH.sub.2 OH, --COOR.sup.1, --CONR.sup.1.sub.2, --COOOR.sup.2 Ph and --R.sup.2 Phwherein R.sup.1 is a hydrogen atom, a C.sub.1 -C.sub.5 alkyl group or an aromatic group, R.sup.2 is a divalent organic group and Ph is an aromatic group, which has good lubricating properties.
    Type: Grant
    Filed: June 1, 1988
    Date of Patent: June 6, 1989
    Assignee: Daikin Industries Ltd.
    Inventors: Takashi Tohzuka, Sueyoshi Ishikawa, Katsuyoshi Kubo, Yoshitaka Honda, Yukio Ohmure, Norio Kataoka
  • Patent number: 4724092
    Abstract: A fluorine-containing grease composition comprising a halogen-containing polyether of the formula:--(CH.sub.2 CF.sub.2 CF.sub.2 O).sub.a --(CHClCF.sub.2 CF.sub.2 O).sub.b --(CCl.sub.2 CF.sub.2 CF.sub.2 O).sub.c --(CHFCF.sub.2 CF.sub.2 O).sub.d --(CFClCF.sub.2 CF.sub.2 O).sub.e --(CF.sub.2 CF.sub.2 CF.sub.2 O).sub.f --(I)wherein a, b, c, d, e and f are each an integer not less than 0 and satisfy the following equations:2.ltoreq.a+b+c+d+e+f.ltoreq.200and,1.ltoreq.a+c+d+fand 0.5 to 60% by weight of a fluororesin base on the weight of the whole composition, which has good chemical and heat resistance and is used in a high temperature environment.
    Type: Grant
    Filed: November 7, 1985
    Date of Patent: February 9, 1988
    Assignee: Daikin Industries Ltd.
    Inventors: Shoshin Fukui, Shuhei Shimasaki, Takashi Tohzuka
  • Patent number: 4719052
    Abstract: 2,2,3-trifluoropropionyl fluoride is prepared by opening the ring of tetrafluorooxetane in the presence of a catalyst. Analogously, a novel 2,2-difluoropropionic acid derivative of the formula:XCH.sub.2 CF.sub.2 COY (I)wherein X is chlorine, bromine, iodine, a group of the formula:R.sub.1 O-- (II)orR.sub.2 COO-- (III)wherein R.sub.1 R.sub.2 are each an aliphaic or halogenated aliphatic hydrocarbon group having 1 to 8 carbon atoms or an aromatic hydrocarbon group having 6 to 8 carbon atoms optionally bearing at least one substituent, or a group of the formula:X'CH.sub.2 CF.sub.2 CF.sub.2 O-- (IV)wherein X' is fluorine, chlorine, bromine, iodine, the group of the formula: R.sub.1 O--or R.sub.2 COO--; and Y is fluorine or a group of the formula:--OR.sub.3 (V)wherein R.sub.
    Type: Grant
    Filed: December 20, 1984
    Date of Patent: January 12, 1988
    Assignee: Daikin Industries Ltd.
    Inventors: Yohnosuke Ohsaka, Takashi Tohzuka, Shoji Takaki, Yoshio Negishi, Satoru Kohno
  • Patent number: 4296265
    Abstract: Hexafluoropropene oligomers are prepared from hexafluoropropene in a high conversion by contacting gaseous hexafluoropropene with a catalyst comprising an alkali metal fluoride supported on activated charcoal or nickel oxide.
    Type: Grant
    Filed: July 18, 1980
    Date of Patent: October 20, 1981
    Assignee: Daikin Kogyo Co., Ltd.
    Inventors: Yohnosuke Ohsaka, Takashi Tohzuka
  • Patent number: 4288376
    Abstract: Hexafluoropropene oxide is prepared with good conversion and high selectivity by reacting hexafluoropropene with oxygen in the presence of at least one barium compound selected from the group consisting of barium oxide, barium hydroxide and barium salts as a catalyst.
    Type: Grant
    Filed: July 18, 1980
    Date of Patent: September 8, 1981
    Assignee: Daikin Kogyo Co., Ltd.
    Inventors: Yohnosuke Ohsaka, Takashi Tohzuka
  • Patent number: 4284822
    Abstract: Hexafluoroacetone is prepared by reacting hexafluoropropene with oxygen in the presence of a metal oxide selected from the group consisting of tin oxides, iron oxides and indium oxides. These metal oxides can be readily handled and assure a stable reaction.
    Type: Grant
    Filed: March 28, 1980
    Date of Patent: August 18, 1981
    Assignee: Daikin Kogyo Co., Ltd.
    Inventors: Takashi Tohzuka, Yohnosuke Ohsaka
  • Patent number: 4238416
    Abstract: A method for isomerization of fluorinated epoxy compounds by contacting with a catalyst to produce the corresponding fluorinated carbonyl compounds, which is characterized in that the catalyst is a fluorinated alumina or a fluorinated silica alumina.
    Type: Grant
    Filed: January 29, 1979
    Date of Patent: December 9, 1980
    Assignee: Daikin Kogyo Co., Ltd.
    Inventors: Takashi Tohzuka, Yohnosuke Ohsaka
  • Patent number: 4165340
    Abstract: A process for preparing hexafluoropropanone-2 from hexafluoropropene by one step reaction which comprises contacting hexafluoropropene and oxygen with a fluorinated alumina or a fluorinated silica-alumina as a catalyst in the presence or absence of water, provided that water is present when the catalyst is the fluorinated alumina.
    Type: Grant
    Filed: August 19, 1977
    Date of Patent: August 21, 1979
    Assignee: Daikin Kogyo Co., Ltd.
    Inventors: Takashi Tohzuka, Yohnosuke Ohsaka
  • Patent number: 4070439
    Abstract: Antimony pentachloride is recovered from a spent antimony catalyst mixture in a simple manner by bubbling through the spent catalyst mixture an inactive gas such as trichlorotrifluoroethane at an elevated temperature to convert and to remove high melting point or high sublimating point substances as lower boiling point substances; converting fluorinated antimony into chlorinated antimony by means of a chlorinating agent such as carbon tetrachloride; converting antimony (III) into antimony (V) by oxidation with chlorine; and recovering antimony pentachloride by distillation. The antimony pentachloride thus recovered may readily be used as a catalyst for fluorination of a chlorinated hydrocarbon by reaction with hydrogen fluoride.
    Type: Grant
    Filed: August 3, 1976
    Date of Patent: January 24, 1978
    Assignee: Daikin Kogyo Co., Ltd.
    Inventors: Yonosuke Osaka, Takashi Tohzuka