Patents by Inventor Haruyoshi Takatsu

Haruyoshi Takatsu 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).

  • Publication number: 20080149889
    Abstract: A nematic liquid crystal composition having a negative dielectric constant anisotropy, comprising one or more compounds selected from the compounds represented by (IA) and (IB) of 10-70% by mass, one or more compounds selected from the compounds represented by (IIA) to (IID) of 10-70% by mass, the total content of one or more compounds selected from the compounds represented by (IA) to (IID) being 35-80% by mass, and a compound represented by (III) of 20-65% by mass: wherein R1 to R14 each independently represents an alkyl group having 1 to 10 carbon atoms, etc.; Z1 to Z11 each independently represents a single bond, etc.; Z1 to Z6 and Z9 to Z11 each independently represents —CF2O—, etc.; l and m represent 0 or 1; rings A, B, C and D represent a trans-1,4-cyclohexylene group, etc.; and rings B, C and D represent a trans-1,4-cyclohexenylene group.
    Type: Application
    Filed: December 19, 2003
    Publication date: June 26, 2008
    Applicant: DAINIPPON INK AND CHEMICALS, INC.
    Inventors: Yoshikiyo Tanaka, Kiyofumi Takeuchi, Haruyoshi Takatsu
  • Patent number: 7198827
    Abstract: A nematic liquid crystal composition comprising compounds of the general formulas (I-1) to (I-5) each having naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2,6-diyl, and a liquid display device using the same. This nematic liquid crystal composition broadens the operating temperature range of liquid crystal display characteristics due to an improvement in co-solubility and storage at low temperature, thereby making it possible to improve a reduction in driving voltage and a change in temperature and to attain comparatively fast response characteristics for a predetermined driving voltage. Accordingly, the nematic liquid crystal composition is best suited for use as TN, STN, TFT, IPS, MVA, OCB, ECB, PC, PNLC, PDLC, PSCT or the like.
    Type: Grant
    Filed: September 10, 1999
    Date of Patent: April 3, 2007
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Kiyofumi Takeuchi, Haruyoshi Takatsu, Hirokazu Yanagihara
  • 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
  • Patent number: 7108896
    Abstract: A method of increasing helical twisting power (HTP) in an optically active compound used in a liquid crystal material is provided. An optically active compound which exhibits a large HTP value is also provided. Furthermore, a liquid crystal composition which exhibits a high upper temperature limit of the liquid crystal after the addition of the optically active compound, and a liquid crystal display device using the same are provided. In a method, an HTP of a compound having a partial structure represented by formula (A), which has an asymmetric carbon atom, is increased by replacing the partial structure represented by formula (A) by a partial structure represented by formula (B) (wherein * represents the position of an asymmetric carbon atom, Y1 represents a substituent such as an alkyl group and a halogen).
    Type: Grant
    Filed: June 24, 2003
    Date of Patent: September 19, 2006
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Hidetoshi Nakata, Makoto Sasaki, Kiyofumi Takeuchi, Haruyoshi Takatsu
  • 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: 20040021128
    Abstract: A method of increasing helical twisting power (HTP) in an optically active compound used in a liquid crystal material is provided. An optically active compound which exhibits a large HTP value is also provided. Furthermore, a liquid crystal composition which exhibits a high upper temperature limit of the liquid crystal after the addition of the optically active compound, and a liquid crystal display device using the same are provided. In a method, an HTP of a compound having a partial structure represented by formula (A), which has an asymmetric carbon atom, is increased by replacing the partial structure represented by formula (A) by a partial structure represented by formula (B).
    Type: Application
    Filed: June 24, 2003
    Publication date: February 5, 2004
    Applicant: Dainippon Ink and Chemicals, Inc.
    Inventors: Hidetoshi Nakata, Makoto Sasaki, Kiyofumi Takeuchi, Haruyoshi Takatsu
  • Patent number: 6620467
    Abstract: A supertwisted nematic liquid crystal display having twist angle of 180 to 270° C. and comprising: a pair of substrates each having an orientation-controlling layer and a transparent electrodel; a liquid crystal layer comprising a liquid crystal composition, which is sandwiched by the substrates; and at least one polarizing sheet provided on at least one of the substrates, wherein the liquid crystal composition comprises: at least one compound represented by formula (I): and at least one compound represented by formula (II): and wherein said liquid crystal composition has a nematic-isotropic phase transition temperature of 75 to 150° C. and a refractive index anisotropy (&Dgr;n) of 0.07 to 0.25. The symbols in formulae (I) and (II) are defined in the specification.
    Type: Grant
    Filed: July 25, 2001
    Date of Patent: September 16, 2003
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Go Sudo, Shotaro Kawakami, Haruyoshi Takatsu, Hiroyuki Ohnishi, Naoe Katoh
  • Patent number: 6607791
    Abstract: A liquid crystal composition comprises as a first liquid crystal component a compound represented by the following general formula (I): and as a second liquid crystal component a compound selected from the group consisting of compounds represented by the following general formulae (II) and (III): and has a nematic phase upper temperature limit of 75° C. or higher and &Dgr;n of from 0.07 to 0.18.
    Type: Grant
    Filed: October 27, 2000
    Date of Patent: August 19, 2003
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Shinji Ogawa, Masashi Osawa, Hiroyuki Ohnishi, Haruyoshi Takatsu, Kiyofumi Takeuchi, Shotaro Kawakami, Takeshi Kuriyama
  • 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: 6562421
    Abstract: A supertwisted nematic liquid crystal display comprising: a pair of substrates each having a liquid crystal orientation-controlling layer and a transparent electrode; a liquid crystal material held between said substrates; and at least one polarizing sheet provided on at least one of said substrates, wherein said liquid crystal material comprises: (a) a compound represented by formula (I): and (b) at least one compound selected from the group consisting of: compounds represented by formula (II): and compounds represented by formula (III):
    Type: Grant
    Filed: August 29, 2001
    Date of Patent: May 13, 2003
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Go Sudo, Takeshi Kuriyama, Shotaro Kawakami, Hiroyuki Ohnishi, Haruyoshi Takatsu
  • Publication number: 20020163487
    Abstract: A supertwisted nematic liquid crystal display comprising: a pair of substrates each having a liquid crystal orientation-controlling layer and a transparent electrode; a liquid crystal material held between said substrates; and at least one polarizing sheet provided on at least one of said substrates, wherein said liquid crystal material comprises: (a) a compound represented by formula (I): 1
    Type: Application
    Filed: August 29, 2001
    Publication date: November 7, 2002
    Applicant: DAINIPPON INK AND CHEMICALS, INC
    Inventors: Go Sudo, Takeshi Kuriyama, Shotaro Kawakami, Hiroyuki Ohnishi, Haruyoshi Takatsu
  • 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
  • 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
  • Publication number: 20020033929
    Abstract: A supertwisted nematic liquid crystal display having twist angle of 180 to 270° C.
    Type: Application
    Filed: July 25, 2001
    Publication date: March 21, 2002
    Applicant: Dainippon Ink and Chemicals, Inc.
    Inventors: Go Sudo, Shotaro Kawakami, Haruyoshi Takatsu, Hiroyuki Ohnishi, Naoe Katoh
  • 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: 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: 5863457
    Abstract: The present invention provides a novel polymerizable liquid crystal composition which can be used as an optical material, display material or recording material. More particularly, the present invention provides an optically anisotropic film comprising a photopolymerization product of such a polymerizable liquid crystal composition having a high orientation state fixed therein which functions to control light and is suitable for the application in the field of optoelectronics, liquid crystal display, etc. The present invention further provides a process for the preparation of such an optically anisotropic film. Moreover, the present invention provides a liquid crystal device comprising the foregoing optically anisotropic film.
    Type: Grant
    Filed: June 4, 1996
    Date of Patent: January 26, 1999
    Assignee: Dainippon Ink and Chemicals, Inc.
    Inventors: Hiroshi Hasebe, Haruyoshi Takatsu, Kiyofumi Takeuchi