Patents by Inventor Joji Kawamura

Joji Kawamura 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: 10558084
    Abstract: A method of fabricating a liquid crystal display device includes forming a first alignment layer on a first substrate, forming a second alignment layer on a second substrate, disposing the first substrate and the second substrate such that the first alignment layer and the second alignment layer are spaced apart, forming a liquid crystal layer including liquid crystal molecules between the first alignment layer and the second alignment layer and forming an electrode layer on one of the first substrate and the second substrate, the electrode layer applying an electric field to the liquid crystal molecules along a direction parallel to the first and second substrates, the forming the first alignment layer including applying a copolymer solution including first moieties and second moieties, and the first moieties have affinity with the first substrate, and the second moieties have compatibility with the liquid crystal molecules and heating the first alignment layer.
    Type: Grant
    Filed: March 14, 2019
    Date of Patent: February 11, 2020
    Assignees: LG DISPLAY CO., LTD., TOKYO INSTITUTE OF TECHNOLOGY
    Inventors: Osamu Sato, Joji Kawamura, Masatoshi Tokita, Junji Watanabe
  • Publication number: 20190212591
    Abstract: A method of fabricating a liquid crystal display device includes forming a first alignment layer on a first substrate, forming a second alignment layer on a second substrate, disposing the first substrate and the second substrate such that the first alignment layer and the second alignment layer are spaced apart, forming a liquid crystal layer including liquid crystal molecules between the first alignment layer and the second alignment layer and forming an electrode layer on one of the first substrate and the second substrate, the electrode layer applying an electric field to the liquid crystal molecules along a direction parallel to the first and second substrates, the forming the first alignment layer including applying a copolymer solution including first moieties and second moieties, and the first moieties have affinity with the first substrate, and the second moieties have compatibility with the liquid crystal molecules and heating the first alignment layer.
    Type: Application
    Filed: March 14, 2019
    Publication date: July 11, 2019
    Applicants: LG DISPLAY CO., LTD., TOKYO INSTITUTE OF TECHNOLOGY
    Inventors: Osamu SATO, Joji KAWAMURA, Masatoshi TOKITA, Junji WATANABE
  • Patent number: 10344211
    Abstract: There is provided a liquid crystal composition including at least one compound represented by General Formula (i) and at least one compound represented by General Formula (N). The total amount of the compound represented by General Formula (i) is 10% by mass or greater. In the liquid crystal composition and the liquid crystal display element using the composition, the liquid crystal composition has a positive ?? and a flat transmission characteristic curve. Therefore, gradation characteristics are easily controlled. Furthermore, display defects due to burn-in, dropping marks, and the like can be suppressed, and therefore excellent display quality is exhibited. The liquid crystal display element using this liquid crystal composition can be also provided.
    Type: Grant
    Filed: December 8, 2015
    Date of Patent: July 9, 2019
    Assignee: DIC CORPORATION
    Inventors: Shiro Taniguchi, Joji Kawamura
  • Patent number: 10316251
    Abstract: A liquid crystal composition having negative dielectric anisotropy, large refractive index anisotropy, and low viscosity and containing as a first component, one or two or more compounds represented by general formula (I) and, as a second component, one or two or more compounds represented by general formula (II), wherein dielectric anisotropy (??) at 25° C. is ?2.0 or less. Also, a liquid crystal display device having high contrast, fast response, and excellent display quality without causing image sticking and display defects.
    Type: Grant
    Filed: August 22, 2017
    Date of Patent: June 11, 2019
    Assignee: DIC CORPORATION
    Inventors: Takeshi Kuriyama, Joji Kawamura
  • Patent number: 10281770
    Abstract: A liquid crystal display device according to an embodiment includes a light source; a first substrate on which a first alignment layer is formed; a second substrate on which a second alignment layer is formed; a liquid crystal layer between the first and second alignment layers; and an electrode layer on one of the first and second substrates, the electrode layer applying an electric field to liquid crystal molecules of the liquid crystal layer along a direction parallel to the first and second substrates, wherein when the electric field is applied, the liquid crystal molecules are twistedly arranged from the second alignment layer to the first alignment layer.
    Type: Grant
    Filed: March 10, 2017
    Date of Patent: May 7, 2019
    Assignees: LG DISPLAY CO., LTD., TOKYO INSTITUTE OF TECHNOLOGY
    Inventors: Osamu Sato, Joji Kawamura, Masatoshi Tokita, Junji Watanabe
  • Patent number: 10253258
    Abstract: The present invention provides a liquid crystal composition including at least one compound represented by General Formula (1), at least one compound represented by General Formula (2), and at least one compound represented by General Formula (LC1). The liquid crystal composition of the present invention has high refractive index anisotropy (?n) and sufficiently low viscosity (?), achieves a wide nematic phase temperature range by suppressing a decrease in nematic phase-isotropic liquid phase transition temperature (Tni), and exhibits high compatibility. By using the liquid crystal composition of the present invention in a liquid crystal display element, a liquid crystal display element having a high response speed and high practical reliability can be obtained.
    Type: Grant
    Filed: July 28, 2015
    Date of Patent: April 9, 2019
    Assignee: DIC CORPORATION
    Inventors: Shirou Taniguchi, Joji Kawamura
  • Patent number: 10208250
    Abstract: Provided are a liquid crystal composition including at least one or more compounds represented by General Formula (i) and at least one or more compounds represented by General Formula (M-1), in which the dielectric constant anisotropy at 25° C. is larger than 0 and 5 or less; and a liquid crystal display element using this composition. The liquid crystal composition has a positive ??, can have the electrical capacity of the liquid crystal layer (CLC) reduced to a low level, can be driven at a voltage that is practically sufficiently low, and satisfies at least any one of the requirements of maintaining a liquid crystal phase over a wider temperature range, low viscosity, satisfactory solubility at low temperature, high specific resistance or voltage retention rate, and stability to heat or light; and provide an excellent liquid crystal display element.
    Type: Grant
    Filed: December 17, 2014
    Date of Patent: February 19, 2019
    Assignee: DIC CORPORATION
    Inventors: Shirou Taniguchi, Joji Kawamura
  • Patent number: 10000700
    Abstract: The present invention provides a liquid crystal composition having positive dielectric anisotropy and containing at least one compound represented by general formula (LC0): and at least one compound represented by general formula (LC1): R11A11-Z11m11A12-Z12-A13-R12??(LC1) The liquid crystal composition according to the present invention has refractive index anisotropy (?n) adjusted to the desired level and a decrease in nematic phase-isotropic liquid phase transition temperature (Tni) and an increase in the nematic phase lower limit temperature are suppressed so as to achieve a sufficiently low viscosity (?) without degrading the nematic phase temperature range. When the liquid crystal composition of the present invention is used to produce a liquid crystal display device, a highly practical and highly reliable liquid crystal display device with high response speed and capacity for low-voltage drive is obtained.
    Type: Grant
    Filed: July 28, 2015
    Date of Patent: June 19, 2018
    Assignee: DIC CORPORATION
    Inventors: Shirou Taniguchi, Joji Kawamura
  • Patent number: 9963636
    Abstract: The present invention relates to a liquid crystal composition used in a liquid crystal display device. A problem to be solved by the invention is to provide a liquid crystal composition and a liquid crystal display device using the liquid crystal composition, the liquid crystal composition being suitable for a liquid crystal display device, causing little dropping marks during manufacture and realizing stable discharge of a liquid crystal material in an ODF process without degrading characteristics as a liquid crystal display device, such as dielectric anisotropy, bulk viscosity, nematic phase upper limit temperature, rotational viscosity ?1, voltage holding ratio, etc. and image sticking characteristic of a display device. The present invention relates to a liquid crystal composition having negative dielectric anisotropy and containing compounds represented by formula (i) and formula (XIII-1-2) or formula (XIII-1-4) and also relates to a liquid crystal display device using the liquid crystal composition.
    Type: Grant
    Filed: February 12, 2013
    Date of Patent: May 8, 2018
    Assignee: DIC CORPORATION
    Inventors: Yoshinori Iwashita, Joji Kawamura, Makoto Negishi, Shinji Ogawa
  • Patent number: 9938463
    Abstract: There is provided a liquid crystal display device that uses such a liquid crystal composition is also provided. Provided is a liquid crystal composition that includes a first component which is at least one selected from the group consisting of compounds represented by general formula (1) and a second component which is at least one component selected from the group consisting of compounds represented by general formula (2). Also provided is a liquid crystal display device that uses a liquid crystal composition that contains the first component and the second component.
    Type: Grant
    Filed: March 26, 2013
    Date of Patent: April 10, 2018
    Assignee: DIC CORPORATION
    Inventors: Shinji Ogawa, Yoshinori Iwashita, Joji Kawamura, Makoto Negishi
  • Publication number: 20170355906
    Abstract: There is provided a liquid crystal composition including at least one compound represented by General Formula (i) and at least one compound represented by General Formula (N). The total amount of the compound represented by General Formula (i) is 10% by mass or greater. In the liquid crystal composition and the liquid crystal display element using the composition, the liquid crystal composition has a positive ?? and a flat transmission characteristic curve. Therefore, gradation characteristics are easily controlled. Furthermore, display defects due to burn-in, dropping marks, and the like can be suppressed, and therefore excellent display quality is exhibited. The liquid crystal display element using this liquid crystal composition can be also provided.
    Type: Application
    Filed: December 8, 2015
    Publication date: December 14, 2017
    Applicant: DIC Corporation
    Inventors: Shiro Taniguchi, Joji Kawamura
  • Publication number: 20170349829
    Abstract: A liquid crystal composition having negative dielectric anisotropy, large refractive index anisotropy, and low viscosity and containing as a first component, one or two or more compounds represented by general formula (I) and, as a second component, one or two or more compounds represented by general formula (II), wherein dielectric anisotropy (??) at 25° C. is ?2.0 or less. Also, a liquid crystal display device having high contrast, fast response, and excellent display quality without causing image sticking and display defects.
    Type: Application
    Filed: August 22, 2017
    Publication date: December 7, 2017
    Applicant: DIC CORPORATION
    Inventors: Takeshi Kuriyama, Joji Kawamura
  • Patent number: 9828549
    Abstract: There is provided a liquid crystal composition containing any one or two or more of compounds represented by general formula (i) below and any one or two or more of compounds represented by general formula (ii) below.
    Type: Grant
    Filed: February 20, 2013
    Date of Patent: November 28, 2017
    Assignee: DIC CORPORATION
    Inventors: Joji Kawamura, Makoto Negishi, Yoshinori Iwashita
  • Patent number: 9822304
    Abstract: It is an object of the present invention to provide a liquid crystal composition having positive ??, having a liquid crystal phase in a wide temperature range, having high solubility at low temperatures, having high ODF process compatibility, having a high specific resistance and voltage holding ratio, and being insensitive to heat and light. In order to achieve this object, there is provided a liquid crystal composition containing at least one compound represented by the following general formula (i) and at least one compound represented by the following general formula (ii).
    Type: Grant
    Filed: March 25, 2013
    Date of Patent: November 21, 2017
    Assignee: DIC CORPORATION
    Inventors: Joji Kawamura, Makoto Negishi, Yoshinori Iwashita
  • Publication number: 20170261783
    Abstract: A liquid crystal display device according to an embodiment includes a light source; a first substrate on which a first alignment layer is formed; a second substrate on which a second alignment layer is formed; a liquid crystal layer between the first and second alignment layers; and an electrode layer on one of the first and second substrates, the electrode layer applying an electric field to liquid crystal molecules of the liquid crystal layer along a direction parallel to the first and second substrates, wherein when the electric field is applied, the liquid crystal molecules are twistedly arranged from the second alignment layer to the first alignment layer.
    Type: Application
    Filed: March 10, 2017
    Publication date: September 14, 2017
    Applicants: LG DISPLAY CO., LTD., TOKYO INSTITUTE OF TECHNOLOGY
    Inventors: Osamu SATO, Joji KAWAMURA, Masatoshi TOKITA, Junji WATANABE
  • Publication number: 20170260451
    Abstract: The liquid crystal composition of the present invention can be used in a liquid crystal display element of an IPS type or a TN type in which display defects such as burn-in and dropping marks in high speed response are unlikely to be generated. Since the liquid crystal composition contains a component which is a dielectrically positive component including a dielectrically positive compound and a dielectrically neutral component of which dielectric anisotropy is greater than ?2 and less than +2, the liquid crystal composition has excellent characteristics that the liquid crystal composition has a liquid crystal phase in a wide temperature range, low viscosity, excellent solubility at a low temperature, high specific resistance and a high voltage holding ratio, and is stable with respect to heat and light.
    Type: Application
    Filed: May 30, 2017
    Publication date: September 14, 2017
    Applicant: DIC CORPORATION
    Inventor: Joji Kawamura
  • Patent number: 9745513
    Abstract: The present invention provides a liquid crystal composition having negative dielectric anisotropy, large refractive index anisotropy, and low viscosity and containing as a first component, one or two or more compounds represented by general formula (I) and, as a second component, one or two or more compounds represented by general formula (II), wherein dielectric anisotropy (??) at 25° C. is ?2.0 or less. Also, provided is a liquid crystal display device having high contrast, fast response, and excellent display quality without causing image sticking and display defects.
    Type: Grant
    Filed: October 31, 2013
    Date of Patent: August 29, 2017
    Assignee: DIC CORPORATION
    Inventors: Takeshi Kuriyama, Joji Kawamura
  • Publication number: 20170218269
    Abstract: The present invention provides a liquid crystal composition including at least one compound represented by General Formula (1), at least one compound represented by General Formula (2), and at least one compound represented by General Formula (LC1). The liquid crystal composition of the present invention has high refractive index anisotropy (?n) and sufficiently low viscosity (?), achieves a wide nematic phase temperature range by suppressing a decrease in nematic phase-isotropic liquid phase transition temperature (Tni), and exhibits high compatibility. By using the liquid crystal composition of the present invention in a liquid crystal display element, a liquid crystal display element having a high response speed and high practical reliability can be obtained.
    Type: Application
    Filed: July 28, 2015
    Publication date: August 3, 2017
    Applicant: DIC CORPORATION
    Inventors: Shirou Taniguchi, Joji Kawamura
  • Publication number: 20170198219
    Abstract: The present invention provides a liquid crystal composition having positive dielectric anisotropy and containing at least one compound represented by general formula (LC0): and at least one compound represented by general formula (LC1): R11?A11-Z11?m11A12-Z12-A13-R12??(LC1) The liquid crystal composition according to the present invention has refractive index anisotropy (?n) adjusted to the desired level and a decrease in nematic phase-isotropic liquid phase transition temperature (Tni) and an increase in the nematic phase lower limit temperature are suppressed so as to achieve a sufficiently low viscosity (?) without degrading the nematic phase temperature range. When the liquid crystal composition of the present invention is used to produce a liquid crystal display device, a highly practical and highly reliable liquid crystal display device with high response speed and capacity for low-voltage drive is obtained.
    Type: Application
    Filed: July 28, 2015
    Publication date: July 13, 2017
    Applicant: DIC Corporation
    Inventors: Shirou TANIGUCHI, Joji KAWAMURA
  • Patent number: 9695361
    Abstract: The liquid crystal composition of the present invention can be used in a liquid crystal display element of an IPS type or a TN type in which display defects such as burn-in and dropping marks in high speed response are unlikely to be generated. Since the liquid crystal composition contains a component which is a dielectrically positive component including a dielectrically positive compound and a dielectrically neutral component of which dielectric anisotropy is greater than ?2 and less than +2, the liquid crystal composition has excellent characteristics that the liquid crystal composition has a liquid crystal phase in a wide temperature range, low viscosity, excellent solubility at a low temperature, high specific resistance and a high voltage holding ratio, and is stable with respect to heat and light.
    Type: Grant
    Filed: October 5, 2012
    Date of Patent: July 4, 2017
    Assignee: DIC CORPORATION
    Inventor: Joji Kawamura