Patents by Inventor Yasuyuki Koizumi

Yasuyuki Koizumi 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: 6703083
    Abstract: Silicon compounds having a low viscosity and a low threshold voltage and improved mutual solubility, a liquid crystal composition comprising the same and a liquid crystal display using the liquid crystal composition. The silicon compound is represented by formula (1): wherein Y1 is, for example, alkylene having 1 to 10 carbon atoms, Y2 is, for example, hydrogen, halogen, —CN, —C≡C—CN, or alkyl having 1 to 10 carbon atoms; A1, A2, A3, and A4 each are, for example, independently 1,4-cyclohexylene, 1,4-cyclohexenylene, 1,4-phenylene, or 1,4-phenylene; Z1, Z2 and Z3 each are independently a single bond, —(CH2)2—, —OCH2—, —CH2O—, —CH═CH—, —C≡C—, —(CH2)4—, —O(CH2)3—, —(CH2)3O—, —COO—, —OCO—, —OCF2—, or —CF2O—; and p and q each are independently 0 or 1.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: March 9, 2004
    Assignees: Chisso Corporation, Chisso Petrochemical Corporation
    Inventors: Takashi Kato, Yasuyuki Koizumi, Yasuhiro Kubo, Kanetsugu Terashima
  • Publication number: 20030168632
    Abstract: Silicon compounds having a low viscosity and a low threshold voltage and improved mutual solubility, a liquid crystal composition comprising the same and a liquid crystal display using the liquid crystal composition.
    Type: Application
    Filed: February 28, 2002
    Publication date: September 11, 2003
    Inventors: Takashi Kato, Yasuyuki Koizumi, Yasuhiro Kubo, Kanetsugu Terashima
  • Patent number: 6319570
    Abstract: The invention is to provide liquid crystalline compounds which have a low viscosity, high negative dielectric anisotropy, high resistivity, and high voltage holding ratio, and are stable against heat and ultraviolet light; to provide liquid crystal compositions comprising the liquid crystalline compound; and to provide liquid crystal display devices using the liquid crystal composition therein; the liquid crystalline compound is expressed by the general formula (1)  wherein R1 and Y1 represent an alkyl group having 1 to 20 carbon atoms; X1, X2, and X3 independently represent single bond, 1,2-ethylene group, vinylene group, —COO—, —CF2O—, or —OCF2—; ring A1, ring A2, ring A3, and ring A4 independently represent trans-1,4-cycloliexylene, or 1,4-phenylene hydrogen atom on the ring may be replaced by fluorine atom or chlorine atom provided that at least one of ring A2, ring A3, and ring A4 represents 2,3-difluoro-1,4-phenylene; m and n are 0 or 1, and ea
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: November 20, 2001
    Assignee: Chisso Corporation
    Inventors: Tugumiti Andou, Shuichi Matsui, Kazutoshi Miyazawa, Hiroyuki Takeuchi, Yasuyuki Koizumi, Yasuko Sekiguchi, Etsuo Nakagawa, Fusayuki Takeshita
  • Patent number: 6190576
    Abstract: The invention is to provide liquid crystalline compounds which have a low viscosity, high negative dielectric anisotropy, high resistivity, and high voltage holding ratio, and are stable against heat and ultraviolet light; to provide liquid crystal compositions comprising the liquid crystalline compound; and to provide liquid crystal display devices using the liquid crystal composition therein; the liquid crystalline compound is expressed by the general formula (1) wherein R1 and Y1 represent an alkyl group having 1 to 20 carbon atoms; X1, X2, and X3 independently represent single bond, 1,2-ethylene group, vinylene group, —COO—, —CF2O—, or —OCF2—; ring A1, ring A2, ring A3, and ring A4 independently represent trans-1,4-cyclohexylene, or 1,4-phenylene hydrogen atom on the ring may be replaced by fluorine atom or chlorine atom provided that at least one of ring A2, ring A3, and ring A4 represents 2,3-difluoro-1,4-phenylene; m and n are 0 or 1, and each elem
    Type: Grant
    Filed: September 30, 1998
    Date of Patent: February 20, 2001
    Assignee: Chisso Corporation
    Inventors: Tugumiti Andou, Shuichi Matsui, Kazutoshi Miyazawa, Hiroyuki Takeuchi, Yasuyuki Koizumi, Yasuko Sekiguchi, Etsuo Nakagawa, Fusayuki Takeshita
  • Patent number: 6174457
    Abstract: A compound represented by the general formula (1) wherein R1 is an alkadienyl group having 4 to 10 carbon atoms in which a hydrogen atom may be substituted by a fluorine atom or the like; R2 is an alkenyl group having 2 to 10 carbon atoms in which a hydrogen atom may be substituted by a fluorine atom or the like; one or more non-adjacent methylene groups (—CH2—) in the alkadienyl group or the alkenyl group may be replaced by —O— or the like; rings A1, A2, A3 and A4 are each 1,4-cyclohexylene, 1,4-phenylene or the like in which a hydrogen atom may be substituted by a halogen atom; Z1, Z2 and Z3 are each a single bond, —CH2CH2—, —CF═CF— or the like; p and q are each 0 or 1. The above compound has a large elastic constant ratio, steep electro-optic characteristics and a little temperature dependence in a low temperature range, and so it is useful for the manufacture of a liquid crystal display device.
    Type: Grant
    Filed: February 11, 1999
    Date of Patent: January 16, 2001
    Assignee: Chisso Corporation
    Inventors: Takashi Kato, Kazutoshi Miyazawa, Shuichi Matsui, Noriyuki Ohnishi, Takashi Katoh, Yasuyuki Koizumi, Hiroyuki Takeuchi, Fusayuki Takeshita, Yasusuke Hisatsune
  • Patent number: 6086964
    Abstract: The present invention is to provide a liquid crystallineThe present invention is concerned with a liquid crystalline compound expressed by general formula (1) ##STR1## wherein R.sub.1 represents cyano group, halogen atom, or a straight or branched alkyl group or halogenated alkyl group having 1 to 20 carbon atoms, one or not-adjacent two CH.sub.2 groups in the alkyl group or halogenated alkyl group may be replaced by oxygen atom or --CH.dbd.CH-- group; R.sub.2 and R.sub.2 ' represent hydrogen atom, halogen atom, or an alkyl group having 1 to 9 carbon atoms; X.sub.1, X.sub.2, and X.sub.3 independently represent --CH.sub.2 CH.sub.2 --, --CO--O--, --O--CO--, --CH.dbd.CH--, --C.tbd.C--, --(CH.sub.2).sub.4 --, --CF.sub.2 O--, --OCF.sub.2 --, --CH.sub.2 O--, --OCH.sub.
    Type: Grant
    Filed: February 2, 1999
    Date of Patent: July 11, 2000
    Assignee: Chisso Corporation
    Inventors: Noriyuki Onishi, Koichi Shibata, Yasuhiro Haseba, Yasuyuki Koizumi, Shuichi Matsui, Kazutoshi Miyazawa, Yasuko Sekiguchi, Etsuo Nakagawa
  • Patent number: 6051288
    Abstract: An object of the present invention is to provide a novel liquid crystalline compound having a large dielectric anisotropy, small change in threshold voltage depending on temperature, and an improved solubility to other liquid crystal materials at low temperatures, and expressed by the following general formula (1): ##STR1## wherein R represents, for example, an alkyl group or alkoxy group having 1 to 10 carbon atoms, m and n are independently 0 or 1, A.sub.1, A.sub.2, and A.sub.3 are independently, for example, trans-1,4-cyclohexylene group, 1,4-phenylene group one or more hydrogen atoms on the ring of which may be replaced by F, Z.sub.1, Z.sub.2, and Z.sub.3 independently represent --COO--, --OCO--, --(CH.sub.2).sub.2 --, --CH.sub.2 O--, --OCH.sub.2 --, or a covalent bond provided that at least one of Z.sub.1, Z.sub.2, and Z.sub.3 represents ester bond, --CH.sub.2 O--, or --OCH.sub.2 --, X represents, for example, CF.sub.3, CF.sub.2 H, and Y represents H or F.
    Type: Grant
    Filed: September 26, 1997
    Date of Patent: April 18, 2000
    Assignee: Chisso Corporation
    Inventors: Tomoyuki Kondo, Yasuhiro Haseba, Yasuyuki Koizumi, Kazutoshi Miyazawa, Norihisa Hachiya, Etsuo Nakagawa
  • Patent number: 6001275
    Abstract: The present invention is concerned with a liquid crystalline compound expressed by general formula (1) ##STR1## wherein R.sub.1 represents cyano group, halogen atom, or a straight or branched alkyl group or halogenated alkyl group having 1 to 20 carbon atoms, one or not-adjacent two CH.sub.2 groups in the alkyl group or halogenated alkyl group may be replaced by oxygen atom or --CH.dbd.CH-- group; R.sub.2 and R.sub.2 ' represent hydrogen atom, halogen atom, or an alkyl group having 1 to 9 carbon atoms; X.sub.1, X.sub.2, and X.sub.3 independently represent --CH.sub.2 CH.sub.2 --, --CO--O--, --O--CO--, --CH.dbd.CH--, --C.tbd.C--, --(CH.sub.2).sub.4 --, --CF.sub.2 O--, --OCF.sub.2 --, --CH.sub.2 O--, --OCH.sub.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: December 14, 1999
    Assignee: Chisso Corporation
    Inventors: Noriyuki Onishi, Koichi Shibata, Yasuhiro Haseba, Yasuyuki Koizumi, Shuichi Matsui, Kazutoshi Miyazawa, Yasuko Sekiguchi, Etsuo Nakagawa
  • Patent number: 5820784
    Abstract: A liquid crystal composition is disclosed which contains, as the first component, at least one compound expressed by the formula (I-a) or (I-b) and contains, as the second component, at least one compound expressed by any one of the formulas (II-a) to (II-g), each of the formulas being recited in the specification. According to the present invention, a liquid crystal composition which is particularly excellent in compatibility in low temperatures, and has a suitably large .DELTA.n and a small V.sub.th can be provided while satisfying several characteristics required for liquid crystal compositions for AM-LCD.
    Type: Grant
    Filed: February 22, 1996
    Date of Patent: October 13, 1998
    Assignee: Chisso Corporation
    Inventors: Tomoyuki Kondo, Shuichi Matsui, Yasuyuki Koizumi, Koichi Shibata, Yasuhiro Haseba, Norihisa Hachiya, Etsuo Nakagawa, Kazutoshi Miyazawa
  • Patent number: 5776367
    Abstract: A novel liquid crystalline compound having a low viscosity and a high elastic constant ratio and at the same time, a superior compatibility with other known liquid crystalline compounds, and a liquid crystal composition and a liquid crystal display element containing the novel compound, are provided.The compound is an alkenylcyclohexane derivative expressed by the formula (1): ##STR1## wherein R.sup.1 and R.sup.2 represent a linear or branched alkyl group of 1 to 15 carbon atoms or alkenyl group of 2 to 15 carbon atoms; at least one of R.sup.1 and R.sup.2 represents an alkenyl group; in these groups, one or more non-adjacent CH.sub.2 groups may be replaced by oxygen atom, sulfur atom or --C.tbd.C-- group; ring A.sup.1, ring A.sup.2 and ring A.sup.3 each independently represent 1,4-cyclohexylene group wherein one or more CH.sub.2 groups on the ring may be replaced by oxygen atom or sulfur atom, or 1,4-phenylene group wherein one or more CH groups on the ring may be replaced by nitrogen atom; Z.sup.1 and Z.sup.
    Type: Grant
    Filed: June 19, 1996
    Date of Patent: July 7, 1998
    Assignee: Chisso Corporation
    Inventors: Shuichi Matsui, Yasuyuki Koizumi, Takashi Kato, Kazutoshi Miyazawa, Norihisa Hachiya, Etsuo Nakagawa
  • Patent number: 5755994
    Abstract: A novel liquid crystalline compound having a large dielectric anisotropy value, a small change in the threshold voltage depending upon temperatures, and an improved solubility in other liquid crystal materials at low temperatures, and a liquid crystal composition containing the compound are provided,which liquid crystalline compound is expressed by the formula (1) ##STR1## wherein R is H or an alkyl group of 1 to 10C; l is an integer of 1 to 9; m, n and o are each independently 0 or 1; A.sub.1, A.sub.2 and A.sub.3 are each independently trans-1,4-cyclohexylene group, 1,4-phenylene group, one or more H atoms on the ring of which group may be replaced by F, or the like group; Z.sub.1, Z.sub.2 and Z.sub.3 are each independently --COO--, etc., but at least one of them is --COO--; X is CF.sub.3, etc.; and Y.sub.1, and Y.sub.2 are each independently H or F.
    Type: Grant
    Filed: February 22, 1996
    Date of Patent: May 26, 1998
    Assignee: Chisso Corporation
    Inventors: Tomoyuki Kondo, Shuichi Matsui, Yasuyuki Koizumi, Koichi Shibata, Yasuhiro Haseba, Norihisa Hachiya, Etsuo Nakagawa, Kazutoshi Miyazawa
  • Patent number: 5733477
    Abstract: A liquid crystal composition satisfying various characteristics required for a liquid crystal composition and at the same time having a low temperature threshold voltage, a superior low temperature compatibility and a broad range of nematic phase is provided. A liquid crystal composition characterized by containing as a first component, at least one compound expressed by the following formula (1): ##STR1## wherein R.sup.1 represents an alkyl group of 1 to 10 carbon atoms or an alkenyl group of 2 to 10 carbon atoms; A.sup.1 represents trans-1,4-cyclohexylene of 1,4-phenylene wherein one or more hydrogens present on its ring may be replaced by F; X represents OCF.sub.3 or CF.sub.3 ; Y represents H or F; and m represents an integer of 0 to 2, and as a second component, at least compound expressed by the following formulas (2-1) to (2-6): ##STR2## wherein R.sup.2 represents an alkyl group of 1 to 10 carbon atoms.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: March 31, 1998
    Assignee: Chisso Corporation
    Inventors: Tomoyuki Kondo, Yasuhiro Haseba, Yasuyuki Koizumi, Kazutoshi Miyazawa, Norihisa Hachiya, Etsuo Nakagawa
  • Patent number: 5604120
    Abstract: The present invention provides a method for producing optically active endo-2-norborneols, represented by the following formula: ##STR1## and the antipodes, it comprises asymmetrically hydrolysing racemic endo-2-acyloxynorbornane or endo-2-acyloxynorbornane, whose (R)-compound is in excess, having an optical purity of 50-95% ee with lipase derived from Candida genus. The optically active endo-2-norborneol useful for synthesizing intermediates of pharmaceutical preparations in large quantities.
    Type: Grant
    Filed: August 22, 1995
    Date of Patent: February 18, 1997
    Assignee: Chisso Corporation
    Inventors: Hitoshi Yano, Teruyo Sugiura, Yasuyuki Koizumi, Naoyuki Yoshida
  • Patent number: 5518903
    Abstract: The present invention provides a process for producing optically active 3-aminobutanoic acid characterized in that it comprises an asymmetrically hydrolyzing racemic ester of 3-substituted aminobutanoic acid in the presence of a hydrolase, obtaining an optically active ester of 3-substituted aminobutanoic acid and an optically active 3-substituted aminobutanoic acid of an enantiomer of the ester, and treating the above ester represented by the formula (II): ##STR1## to remove the protecting group. In addition, the new ester intermediates represented by the above formula (II) are provided.
    Type: Grant
    Filed: August 11, 1994
    Date of Patent: May 21, 1996
    Assignee: Chisso Corporation
    Inventors: Naoyuki Yoshida, Teruyo Sugiura, Yasuyuki Koizumi
  • Patent number: 5449793
    Abstract: A novel optically active erythro-1-alkanoyloxy-2,4-O-isopropylidene-2,4-dihydroxy-5-substituted pentane expressed by the formula ##STR1## wherein R.sup.1 represents a halogen atom or cyano group and R.sup.2 represents an alkyl group of 1 to 6 carbon atoms, and a process for producing the above compound are provided, the compound being preferably usable as an intermediate for preparing a HMG-CoA reductase inhibitor and the process being practiced under mild conditions and with a high yield.
    Type: Grant
    Filed: May 12, 1994
    Date of Patent: September 12, 1995
    Assignee: Chisso Corporation
    Inventors: Kazutoshi Miyazawa, Teruyo Sugiura, Yasuyuki Koizumi, Naoyuki Yoshida
  • Patent number: 5395766
    Abstract: The present invention provides an optically active trans-2-aryl-1-cyclohexanol derivative represented by the following general formula (I). ##STR1## The compounds can be obtained by transesterifiation reaction of the following compound (II) as a starting material with lipase. ##STR2## The optically active trans-2-aryl-1-cyclohexanol derivative can be used as an asymmetric source of asymmetric Diels-Alder reaction or a starting material of physiological active materials.
    Type: Grant
    Filed: October 29, 1992
    Date of Patent: March 7, 1995
    Assignee: Chisso Corporation
    Inventors: Yasuyuki Koizumi, Naoyuki Yoshida, Teruyo Sugiura, Kazutoshi Miyazawa
  • Patent number: 5395983
    Abstract: R or S-1-phenyl-1,3-propanediols having optical purity of 100% ee were obtained by recrystallization of R or S-1-phenyl-1,3-propanediols having optical purity of 20% ee to below 100% ee, the last diols are represented by the formula, ##STR1## It is possible to obtain optically pure 1-phenyl-3-propanediols from optically impure 1-phenyl-1,3-propanediols by a simple method.
    Type: Grant
    Filed: January 18, 1994
    Date of Patent: March 7, 1995
    Assignee: Chisso Corporation
    Inventors: Kazutoshi Miyazawa, Teruyo Sugiura, Yasuyuki Koizumi, Naoyuki Yoshida
  • Patent number: 5329018
    Abstract: A novel optically active erythro-1-alkanoyloxy-2,4-O-isopropylidene-2,4-dihydroxy-5-substituted pentane expressed by the formula ##STR1## wherein R.sup.1 represents a halogen atom or cyano group and R.sup.2 represents an alkyl group of 1 to 6 carbon atoms, and a process for producing the above compound are provided, the compound being preferably usable as an intermediate for preparing a HMG-CoA reductase inhibitor and the process being practiced under mild conditions and with a high yield.
    Type: Grant
    Filed: June 4, 1993
    Date of Patent: July 12, 1994
    Assignee: Chisso Corporation
    Inventors: Kazutoshi Miyazawa, Teruyo Sugiura, Yasuyuki Koizumi, Naoyuki Yoshida
  • Patent number: 5266728
    Abstract: The present invention provides a method for producing optically active 3-substituted-2-norbornanones which are useful as starting materials for several kinds of physiologically active materials, and to their intermediates, optically active 2-hydroxy-2-norbornanecarboxylic acid and to a method for producing these intermediates.
    Type: Grant
    Filed: August 19, 1992
    Date of Patent: November 30, 1993
    Assignee: Chisso Corporation
    Inventors: Naoyuki Yoshida, Teruyo Sugiura, Kazutoshi Miyazawa, Yasuyuki Koizumi