Patents by Inventor Tsuyoshi Obikawa

Tsuyoshi Obikawa 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: 8144303
    Abstract: A liquid crystal apparatus includes: a liquid crystal panel having a pair of substrates and including a display area; and a case body having an opening in an area corresponding to the display area of the liquid crystal panel and being attached to the liquid crystal panel, in which the case body includes: a plurality of panel-shaped members having a laminated structure including a clearance in the direction of the thickness of the liquid crystal panel, openings provided at portions on the side of one side of the liquid crystal panel and on the side of the other side thereof opposing the one side corresponding to the clearance, a diaphragm formed in the clearance of the plurality of panel-shaped members from the side of the one side toward the side of the other side.
    Type: Grant
    Filed: December 11, 2008
    Date of Patent: March 27, 2012
    Assignee: Seiko Epson Corporation
    Inventors: Koichi Terao, Tsuyoshi Obikawa
  • Publication number: 20090207327
    Abstract: A liquid crystal apparatus includes: a liquid crystal panel having a pair of substrates and including a display area; and a case body having an opening in an area corresponding to the display area of the liquid crystal panel and being attached to the liquid crystal panel, in which the case body includes: a plurality of panel-shaped members having a laminated structure including a clearance in the direction of the thickness of the liquid crystal panel, openings provided at portions on the side of one side of the liquid crystal panel and on the side of the other side thereof opposing the one side corresponding to the clearance, a diaphragm formed in the clearance of the plurality of panel-shaped members from the side of the one side toward the side of the other side.
    Type: Application
    Filed: December 11, 2008
    Publication date: August 20, 2009
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Koichi TERAO, Tsuyoshi Obikawa
  • Patent number: 6650463
    Abstract: A dispersion medium, for dispersing electrophoretic particles in an electrophoretic display device, contains an organic compound having two or more rings in its structural formula, where the organic compound comprises at least about 30% by weight of the dispersion medium. The thus constituted dispersion medium improves the reliability and response of the electrophoretic device. The organic compound comprises one or more of the materials defined by the structural formulae (1) to (4), wherein each of A1 to A6, C1, and C2 are ring compounds.
    Type: Grant
    Filed: March 12, 2002
    Date of Patent: November 18, 2003
    Assignee: Seiko Epson Corporation
    Inventors: Tsuyoshi Obikawa, Makoto Katase, Satoshi Kinoshita, Masamitsu Uehara
  • Publication number: 20020175891
    Abstract: A dispersion medium, for dispersing electrophoretic particles in an electrophoretic display device, contains an organic compound having two or more rings in its structural formula, where the organic compound comprises at least about 30% by weight of the dispersion medium. The thus constituted dispersion medium improves the reliability and response of the electrophoretic device. The organic compound comprises one or more of the materials defined by the structural formulae (1) to (4), wherein each of A1 to A6, C1, and C2 are ring compounds.
    Type: Application
    Filed: March 12, 2002
    Publication date: November 28, 2002
    Inventors: Tsuyoshi Obikawa, Makoto Katase, Satoshi Kinoshita, Masamitsu Uehara
  • Patent number: 5354502
    Abstract: A 1,3-dioxane derivative and a liquid crystal composition containing it as expressed by the general formula ##STR1## (where R is a straight chain alkyl group of carbon number 1 to 10, A is a single bond or --CH.sub.2 CH.sub.2 -- group, n is 0 or 1, and the cyclohexane ring and 1,3-dioxane ring are respectively in trans form is disclosed.) The 1,3-dioxane derivative represented by general formula (I) has a very large dielectric anisotropy and a small birefringence. Liquid crystal compositions containing (I) can be driven at low voltage and will provide a liquid crystal display apparatus with a wide visual angle.
    Type: Grant
    Filed: December 8, 1992
    Date of Patent: October 11, 1994
    Assignee: Seiko Epson Corporation
    Inventors: Tsuyoshi Obikawa, Shuji Ikukawa, Jitsuko Nakayama
  • Patent number: 5238599
    Abstract: Trans-2-phenyl-5-trans-4'-alkylcyclohexyl-1,3-dioxane derivatives represented by the general formula: ##STR1## wherein R is a linear alkyl group of 1 to 10 carbon atoms, A is a single covalent bond or a --CH.sub.2 CH.sub.2 -- group, X is F or CN, Y is F if X is CN or Y is H or F if X is F, and the cyclohexane ring and the 1,3-dioxane ring are trans isomers. The 1,3-dioxane derivatives have large positive dielectric constant anisotropy (.DELTA..epsilon.), small birefringence (.DELTA.n) and have good compatibility with other liquid crystal compounds. The dioxane derivatives may be included in liquid crystal compositions for improved display devices having a low threshold voltage, a low driving voltage and a wide visual angle.
    Type: Grant
    Filed: May 25, 1990
    Date of Patent: August 24, 1993
    Assignee: Seiko Epson Corporation
    Inventors: Tsuyoshi Obikawa, Shuji Ikukawa, Jitsuko Nakayama
  • Patent number: 5200110
    Abstract: 2-phenyl-5-(4'-trans-cyclohexyl) phenyl pyrimidine derivatives represented by the general formula: ##STR1## wherein R is a straight chain alkyl group having 1 to 10 carbon atoms; X is CN or F; Y is F or H; Z is F or H; and when X is F, at least one of Y and Z is H; and the cyclohexane ring is a trans isomer, exhibiting a nematic phase and having a high nematic phase-isotropic liquid phase transition temperature (N-I Point) and large positive dielectric constant anisotropy (.DELTA..epsilon.). The pyrimidine derivatives may be included in liquid crystal compositions for improved display devices having a wide temperature range, including a high N-I point, a low threshold voltage and a low driving voltage.
    Type: Grant
    Filed: April 15, 1992
    Date of Patent: April 6, 1993
    Assignee: Seiko Epson Corporation
    Inventors: Tsuyoshi Obikawa, Shuhei Yamada, Shuji Ikukawa
  • Patent number: 5061400
    Abstract: 2'-fluoro-4"-trans-cyclohexyl-terphenyl derivatives represented by the general formula: ##STR1## wherein the cyclohexyl is the trans isomer, R is a straight chain alkyl having from 1 to 12 carbon atoms, X is a straight chain alkyl having from 1 to 12 carbon atoms, a straight chain alkoxy having from 1 to 12 carbon atoms or --CN and the compounds exhibit the nematic phase. The fluoro-cyclohexyl-terphenyl derivatives have a low crystal-nematic phase transition temperature (C-N point), a high nematic phase-isotropic liquid phase transition temperature (N-I point) and low viscosity and may be included in liquid crystal compositions for improved display devices having a wide temperature range, a low driving voltage and a rapid response speed.
    Type: Grant
    Filed: June 27, 1989
    Date of Patent: October 29, 1991
    Assignee: Seiko Epson Corporation
    Inventor: Tsuyoshi Obikawa
  • Patent number: 5026879
    Abstract: 2-(3', 4'-difluorophenyl)-1,3-dioxane derivatives represented by the general formula: ##STR1## wherein R is a linear alkyl group having from 1 to 8 atoms, and having large positive dielectric constant anisotropy (.DELTA..epsilon.) and small refractive index anisotropy (.DELTA.n). The dioxane derivatives may be included in liquid crystal compositions for improved display devices having a low threshold voltage, a low driving voltage and a wide visual angle.
    Type: Grant
    Filed: March 20, 1990
    Date of Patent: June 25, 1991
    Assignee: Seiko Epson Corporation
    Inventor: Tsuyoshi Obikawa
  • Patent number: 4879060
    Abstract: 2-phenylpyridine derivatives represented by the general formula: ##STR1## wherein when Y is R--, Z is one of R--, RO--, ##STR2## when Y is RO--, Z is one of straight chain pentyl, ##STR3## and when Y is one of Z is one of R--, RO-- and --CN; when Y is --CN, Z is one of RO--, ##STR4## and R is a straight chain alkyl group from 1 to 12 carbon atoms, are disclosed. The 2-phenylpyridine derivatives in accordance with the invention are particularly well-suited for use in nematic liquid crystal compositions for reducing the steepness and response time of the liquid crystal compositions in a liquid crystal display device.
    Type: Grant
    Filed: May 22, 1987
    Date of Patent: November 7, 1989
    Assignee: Seiko Epson Kabushiki Kaisha
    Inventors: Yoshio Shionozaki, Hiroshi Mukai, Tsuyoshi Obikawa, Shuhei Yamada
  • Patent number: 4723018
    Abstract: 2-phenylpyridine derivatives having the general formula: ##STR1## wherein Y is ##STR2## and Z is a straight chain alkyl group having from 1 to 16 carbon atoms, ##STR3## R' is a straight chain alkyl group having from 2 to 12 carbon atoms, R.sup.2 is a straight chain alkyl group having from 1 to 12 carbon atoms, n is an integer from 1 to 10 and * is an asymmetric carbon are provided. The derivatives are stable, have low viscosity, excellent electro-optical response properties and broaden the ferroelectric temperature range when added to ferroelectric liquid crystal compositions.
    Type: Grant
    Filed: January 21, 1987
    Date of Patent: February 2, 1988
    Assignee: Seiko Epson Corporation
    Inventors: Yoshio Shionozaki, Hiroshi Mukai, Tsuyoshi Obikawa, Shuhei Yamada, Rei Miyazaki
  • Patent number: 4684220
    Abstract: 2-phenylpyridine derivatives represented by the general formula: ##STR1## wherein when Y is R--, Z is one of R--, RO--, ##STR2## when Y is RO--, Z is one of straight chain pentyl, ##STR3## and --CN; and when Y is one of ##STR4## Z is one of R--, RO-- and --CN; when Y is --CN, Z is one of RO--, ##STR5## and R is a straight chain alkyl group from 1 to 12 carbon atoms, are disclosed. The 2-phenylpyridine derivatives in accordance with the invention are particularly well-suited for use in nematic liquid crystal compositions for reducing the steepness and response time of the liquid crystal compositions in a liquid crystal display device.
    Type: Grant
    Filed: July 11, 1985
    Date of Patent: August 4, 1987
    Assignee: Seiko Epson Kabushiki Kaisha
    Inventors: Yoshio Shionozaki, Hiroshi Mukai, Tsuyoshi Obikawa, Shuhei Yamada