Patents by Inventor Sadao Takehara

Sadao Takehara 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: 7214835
    Abstract: The present invention provides 1,7,8-trifluoro-2-naphthol and a derivative thereof as intermediates for efficiently producing a trifluoronaphthalene liquid crystal material. A method for efficiently producing a trifluoronaphthalene liquid crystal material using such intermediates is also disclosed. A naphthol derivative having the following general formula (I) is disclosed.
    Type: Grant
    Filed: September 26, 2003
    Date of Patent: May 8, 2007
    Assignee: Dainippon Ink & Chemicals, Inc.
    Inventors: Tetsuo Kusumoto, Yutaka Nagashima, Sadao Takehara, Takashi Matsumoto
  • Patent number: 7145047
    Abstract: Disclosed in a novel liquid-crystalline compound which is a naphthalene derivative useful as an electro-optical liquid crystal display material, a liquid crystal composition containing such naphthalene derivatives and a liquid crystal display device comprising the same. The naphthalene derivative provided by the present invention exhibits an excellent liquid-crystallinity and miscibility with currently widely used liquid crystal compositions or compositions. The addition of the naphthalene derivative makes it possible to drastically lower the threshold voltage of the liquid crystal composition while maintaining its high response. The naphthalene derivative of the present invention is characterized by a large birefringence index. Further, most of the naphthalene derivative of the present invention has no strongly polar group in its molecule and thus can also be used for active matrix driving.
    Type: Grant
    Filed: August 21, 2002
    Date of Patent: December 5, 2006
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Sadao Takehara, Masashi Osawa, Haruyoshi Takatsu, Makoto Negishi
  • Publication number: 20060163537
    Abstract: The present invention provides 1,7,8-trifluoro-2-naphthol and a derivative thereof as intermediates for efficiently producing a trifluoronaphthalene liquid crystal material. A method for efficiently producing a trifluoronaphthalene liquid crystal material using such intermediates is also disclosed. A naphthol derivative having the following general formula (I) is disclosed. A method for producing a trifluoronaphthalene compound having the following general formula (IV), (VI) or (VIII) using the naphthol derivative as a raw material is also disclosed.
    Type: Application
    Filed: September 26, 2003
    Publication date: July 27, 2006
    Applicant: DAINIPPON INK AND CHEMICALS, INC.
    Inventors: Tetsuo Kusumoto, Yutaka Nagashima, Sadao Takehara, Takashi Matsumoto
  • Patent number: 7067179
    Abstract: A novel compound represented by the general formula (I), and a nematic liquid crystal composition incorporating the same. A compound represented by the general formula (I) can be produced industrially extremely easily, as shown in the examples, displays superior compatibility with current general purpose host liquid crystals as a nematic phase, and also shows little crystal precipitation at low temperatures. Moreover, by addition of a small amount of such a compound to a host liquid crystal, the liquid crystal temperature range at low temperatures can be effectively widened without any significant worsening of the various characteristics of the liquid crystal material. Consequently, a compound of the present invention is an extremely useful liquid crystal material which is suitable for various liquid crystal display elements which require a broad operating temperature range.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: June 27, 2006
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Shinji Ogawa, Tatsuo Kawara, Sadao Takehara, Hiroyuki Ohnishi, Kiyofumi Takeuchi, Haruyoshi Takatsu, Gerwald Grahe, Rainer Bruno Frings, Christine Fugger, Cornelia Pithart
  • Patent number: 6913797
    Abstract: The present invention discloses a decahydronaphthalene derivative represented by general formula (I): a liquid crystal composition in which it is contained, and a liquid crystal device in which it is used. The novel decahydronaphthalene derivative of the present invention can be produced industrially extremely easily as shown in the examples, and by adding a small amount to a base liquid crystal, it is possible to have effects that expand the nematic phase temperature range, thereby improving its various characteristics as a nematic liquid crystal. Moreover, the novel decahydronaphthalene derivative of the present invention also has superior co-solubility with base liquid crystals generally used at present. Thus, it is suitable for various types of liquid crystal devices requiring a wide operating temperature range, and is extremely useful as a liquid crystal material.
    Type: Grant
    Filed: August 23, 1999
    Date of Patent: July 5, 2005
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Shinji Ogawa, Hiroyuki Ohnishi, Yutaka Nagashima, Sadao Takehara, Makoto Negishi, Haruyoshi Takatsu, Gerwald Grahe, Rainer Bruno Frings, Christine Fugger, Cornelia Pithart
  • Patent number: 6746728
    Abstract: A tetrahydronaphthalene derivative represented by the general formula (I) and a liquid crystal composition containing the same. A compound represented by the general formula (I) shows superior liquid crystallinity and co-solubility with conventional liquid crystal compounds and compositions. Furthermore, addition of such a compound enables the threshold voltage to be significantly reduced with almost no deleterious effect on the responsiveness. In addition, a compound of the present invention can also be easily produced industrially, is colorless, and is chemically stable. Consequently, liquid crystal compositions containing such a compound are extremely useful as liquid crystals, and are particularly suitable for liquid crystal displays requiring a wide operating temperature range, low voltage driving and a high response speed.
    Type: Grant
    Filed: December 28, 2001
    Date of Patent: June 8, 2004
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Tetsuo Kusumoto, Yoshitaka Saito, Makoto Negishi, Yutaka Nagashima, Sadao Takehara, Haruyoshi Takatsu, Gerwald Grahe, Rainer Bruno Frings, Cornelia Pithart
  • Patent number: 6693223
    Abstract: A novel liquid crystal compound, a nematic liquid crystal composition, and a liquid crystal display system using the composition are disclosed herein. The liquid crystal compound is represented by the general formula (I): wherein R represents a hydrogen atom or a straight chain alkyl group having 1 to 7 carbon atoms and each of X, Y and Z independently represents hydrogen atom or fluorine atom. The nematic liquid crystal composition of the present invention can provide liquid crystal materials in response to desired purposes even by its addition in a small amount without spoiling other characteristics.
    Type: Grant
    Filed: February 27, 2003
    Date of Patent: February 17, 2004
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Kiyofumi Takeuchi, Haruyoshi Takatsu, Sadao Takehara, Masashi Osawa
  • Publication number: 20030136944
    Abstract: Disclosed in a novel liquid-crystalline compound which is a naphthalene derivative useful as an electro-optical liquid crystal display material, a liquid crystal composition containing such naphthalene derivatives and a liquid crystal display device comprising the same. The naphthalene derivative provided by the present invention exhibits an excellent liquid-crystallinity and miscibility with currently widely used liquid crystal compositions or compositions. The addition of the naphthalene derivative makes it possible to drastically lower the threshold voltage of the liquid crystal composition while maintaining its high response. The naphthalene derivative of the present invention is characterized by a large birefringence index. Further, most of the naphthalene derivative of the present invention has no strongly polar group in its molecule and thus can also be used for active matrix driving.
    Type: Application
    Filed: August 21, 2002
    Publication date: July 24, 2003
    Applicant: Dainippon Ink and Chemicals, Inc.
    Inventors: Sadao Takehara, Masashi Osawa, Haruyoshi Takatsu, Makoto Negishi
  • Patent number: 6582626
    Abstract: A polymerizable compound represented by formula (I): wherein Q1 and Q2 each independently represent a hydrogen atom or a methyl group; p and q each independently represent an integer of 2 to 18; X1 and X2 each independently represent a single bond, —O—, —COO— or —OCO—; L1 represents —COO— or —OCO—; L2 represents —CH2CH2COO— or —CH2CH2OCO—; and Y1, Y2 and Y3 each independently represent a hydrogen atom, an alkyl group having 1 to 7 carbon atoms, an alkoxy group having 1 to 7 carbon atoms, an alkanoyl group having 2 to 7 carbon atoms, a cyano group or a halogen atom. Also disclosed are a polymerizable liquid crystal composition containing the compound, and an optically anisotropic medium produced from the composition.
    Type: Grant
    Filed: November 8, 2001
    Date of Patent: June 24, 2003
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Hiroshi Hasebe, Sadao Takehara, Kiyofumi Takeuchi
  • Patent number: 6468607
    Abstract: Disclosed is a novel liquid-crystalline compound which is a naphthalene derivative useful as an electro-optical liquid crystal display material, a liquid crystal composition containing such naphthalene derivatives and a liquid crystal display device comprising the same. The naphthalene derivative provided by the present invention exhibits an excellent liquid-crystallinity and miscibility with currently widely used liquid crystal compositions or compositions. The addition of the naphthalene derivative makes it possible to drastically lower the threshold voltage of the liquid crystal composition while maintaining its high response. The naphthalene derivative of the present invention is characterized by a large birefringence index. Further, most of the naphthalene derivative of the present invention has no strongly polar group in its molecule and thus can also be used for active matrix driving.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: October 22, 2002
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Sadao Takehara, Masashi Osawa, Haruyoshi Takatsu, Makoto Negishi
  • Patent number: 6399035
    Abstract: A reduction purification method of a nitrogen oxide-containing exhaust gas by contacting said nitrogen oxide-containing exhaust gas with a catalyst in an oxidative atmosphere in which an excess amount of oxygen is present and in the presence of a least one reducing agent selected from the group consisting of a hydrocarbon and an oxygen-containing organic compound, wherein said catalyst comprises an alumina having supported thereon (a) tin and (b) at least one selected from the group consisting of ruthenium, palladium, rhodium and indium.
    Type: Grant
    Filed: September 22, 1999
    Date of Patent: June 4, 2002
    Assignees: Cosmo Research Institute, Cosmo Oil Co., Ltd.
    Inventors: Mitsunori Tabata, Katsumi Miyamoto, Tomohiro Yoshinari, Kazuhito Sato, Sadao Takehara
  • Publication number: 20020060310
    Abstract: A polymerizable compound represented by formula (I): 1
    Type: Application
    Filed: November 8, 2001
    Publication date: May 23, 2002
    Applicant: Dainippon Ink and Chemicals, Inc.
    Inventors: Hiroshi Hasebe, Sadao Takehara, Kiyofumi Takeuchi
  • Publication number: 20020053659
    Abstract: A novel liquid crystal compound, a nematic liquid crystal composition, and a liquid crystal display system using the composition are disclosed herein.
    Type: Application
    Filed: April 6, 2001
    Publication date: May 9, 2002
    Applicant: DAINIPPON INK AND CHEMICALS, INC.
    Inventors: Kiyofumi Takeuchi, Haruyoshi Takatsu, Sadao Takehara, Masashi Osawa
  • Patent number: 6287646
    Abstract: A novel liquid crystal compound, a nematic liquid crystal composition, and a liquid crystal display system using the composition are disclosed herein. The liquid crystal compound is represented by the general formula (I): wherein R represents a hydrogen atom or a straight chain alkyl group having 1 to 7 carbon atoms and each of X, Y and Z independently represents hydrogen atom or fluorine atom. The nematic liquid crystal composition of the present invention can provide liquid crystal materials in response to desired purposes even by its addition in a small amount without spoiling other characteristics.
    Type: Grant
    Filed: November 30, 1998
    Date of Patent: September 11, 2001
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Kiyofumi Takeuchi, Haruyoshi Takatsu, Sadao Takehara, Masashi Osawa
  • Patent number: 6030590
    Abstract: A reduction purification method of a nitrogen oxide-containing exhaust gas by contacting said nitrogen oxide-containing exhaust gas with a catalyst in an oxidative atmosphere in which an excess amount of oxygen is present and in the presence of at least one reducing agent selected from the group consisting of a hydrocarbon and an oxygen-containing organic compound, wherein said catalyst comprises an alumina having supported thereon (a) tin and (b) at least one selected from the group consisting of ruthenium, palladium, rhodium and indium.
    Type: Grant
    Filed: December 26, 1996
    Date of Patent: February 29, 2000
    Assignees: Cosmo Research Institute, Cosmo Oil Co., Ltd.
    Inventors: Mitsunori Tabata, Katsumi Miyamoto, Tomohiro Yoshinari, Kazuhito Sato, Sadao Takehara
  • Patent number: 6010642
    Abstract: Disclosed is to provide an azine derivative as a novel liquid crystal compound, a novel process for the preparation of an asymmetrical azine in a high reaction yield with an extremely small amount of by-products such as symmetrical azines, a nematic liquid crystal composition containing the azine derivative which exhibits a broad driving temperature range and an excellent response for the desired high birefringence index, a liquid crystal display device such as TN-LCD, STN-LCD and TFT-LCD having improved electro-optical properties comprising the liquid crystal composition as a constituent material, and a light-scattering type liquid crystal display system which exhibits a suppressed memory phenomenon, a higher uniformity in turbidity for display and improved display properties and response against temperature change while maintaining and improving the required display properties such as fast switching time, lower voltage driving, higher light-control layer resistivity and higher contrast ratio even in the for
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: January 4, 2000
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Haruyoshi Takatsu, Sadao Takehara, Kiyofumi Takeuchi, Makoto Negishi, Norie Osawa, Masashi Osawa, Shinji Ogawa, Hirokazu Yanagihara
  • Patent number: 5536443
    Abstract: A liquid crystal display comprising a compound of the formula ##STR1## wherein each of Y.sup.1 and Y.sup.2 is independently F, Cl, CN, OCN, SCN, OCF.sub.3, OCF.sub.2 H, OCF.sub.2 CF.sub.3, CF.sub.3, R, --OR, --COOR or --OCOR, wherein R is alkyl, alkenyl or alkoxyalkyl, provided that at least one of Y.sup.1 and Y.sup.2 is R, --OR, --COOR or --OCOR; each of Z, Z.sup.1, Z.sup.2, Z.sup.3 and Z.sup.4 is independently a single bond. CH.sub.2 CH.sub.2 --, --CH.dbd.CH--, --C.dbd.C--, --COO--, --OCO--, --CH.sub.2 O--, OCH.sub.2 --, --(CH.sub.2).sub.4 --, --(CH.sub.2).sub.3 --O-- or --O--(CH.sub.2).sub.3 --: ring A is a group of formula (II): ##STR2## wherein each of X.sup.1, X.sup.2, X.sup.3, X.sup.4, X.sup.5, X.sup.6, X.sup.7, X.sup.8, X.sup.9, and X.sup.
    Type: Grant
    Filed: April 25, 1995
    Date of Patent: July 16, 1996
    Assignee: Dainippon Ink & Chemicals, Inc.
    Inventors: Haruyoshi Takatsu, Sadao Takehara, Kiyohumi Takeuchi, Masashi Osawa, Shinji Ogawa, Norie Ishida
  • Patent number: 5474707
    Abstract: A cyclic hydrocarbon derivative represented by formula (I): ##STR1## wherein each of Y.sup.1 and Y.sup.2 is independently F, Cl, CN, OCN, SCN, OCF.sub.3, OCF.sub.2 H, OCF.sub.2 CF.sub.3, CF.sub.3, R, --OR, --COOR or --OCOR, wherein R is alkyl, alkenyl or alkoxyalkyl, provided that at least one of Y.sup.1 and Y.sup.2 is R, --OR, --COOR or --OCOR; each of Z, Z.sup.1, Z.sup.2, Z.sup.3 and Z.sup.4 is independently a single bond, --CH.sub.2 CH.sub.2 --, --CH.dbd.CH--, --C.tbd.C--, --COO--, --OCO--, --CH.sub.2 O--, OCH.sub.2 --, --(CH.sub.2).sub.4 --, --(CH.sub.2).sub.3 --O-- or --O--(CH.sub.2).sub.3 --; ring A is group of formula (II): ##STR2## wherein each of X.sup.1, X.sup.2, X.sup.3, X.sup.4, X.sup.5, X.sup.6, X.sup.7, X.sup.8, X.sup.9, and X.sup.
    Type: Grant
    Filed: July 21, 1994
    Date of Patent: December 12, 1995
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Haruyoshi Takatsu, Sadao Takehara, Kiyohumi Takeuchi, Masashi Osawa, Shinji Ogawa, Norie Ishida
  • Patent number: 5324451
    Abstract: A compound represented by formula (I): ##STR1## wherein R.sub.1 represents an alkyl group having from 1 to 18 carbon atoms; R.sub.2 represents an alkyl group having from 2 to 16 carbon atoms; rings A, B, C, and D each represents a 1,4-phenylene group or a 1,4-phenylene group having one or two halogen atoms; Y represents a single bond, ##STR2## m and n each represents 0 or 1; p represents 0, 1, or 2; q represents 0 or an integer of from 1 to 6; and C* and C** each represents an asymmetric carbon atom in an (S)- or (R)-configuration, and a liquid crystal composition containing the compound of formula (I). The compound of formula (I) is a chiral liquid crystal compound exhibiting large spontaneous polarization, a long helical pitch, an SC* phase in a broad temperature range including room temperature, satisfactory orientation, and a high rate of response.
    Type: Grant
    Filed: April 20, 1992
    Date of Patent: June 28, 1994
    Assignees: Dainippon Ink and Chemicals, Inc., Kawamura Institute of Chemical Research
    Inventors: Sadao Takehara, Tadao Shoji, Hiroshi Ogawa, Toru Fujisawa, Masashi Osawa
  • Patent number: 5128472
    Abstract: A 2,5-disubstituted pyrizine derivative and a 2,5-disubstituted pyrimidine derivative of the formula (I): ##STR1## wherein R.sup.1 and R.sup.2 each independently represents a straight-chain or branched alkyl group containing 1 to 20 carbon atoms;X represents a halogen atom; and ##STR2## represents a pyrazine-2,5-diyl or a pyrimidine-2,5-diyl group; each useful as an electrooptical display material are disclosed. Further a liquid crystal composition comprising said compounds as well as a ferroelectric display device wherein said liquid crystal composition is used are disclosed.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: July 7, 1992
    Assignees: Dainippon Ink and Chemicals, Inc., Kawamura Institute of Chemical Research
    Inventors: Masashi Osawa, Tadao Shoji, Sadao Takehara, Hiroshi Ogawa, Toru Fujisawa, Takeshi Kuriyama, Kayoko Nakamura