Patents by Inventor Kyoichi Oka

Kyoichi Oka 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: 7018455
    Abstract: An ink composition, a recording medium or printed matter containing a compound expressed by General Formula 1 The compound has a weight reduction after 1 hour at 60°C. of no more than 1%. This makes it possible to provide the ink composition, a recording medium, printed matter, and an ink jet recording method wherein a light resistance of the printed matter is excellent, there is no ink clogging, and a high-quality image with almost no yellowing of the printed matter can be obtained.
    Type: Grant
    Filed: March 21, 2002
    Date of Patent: March 28, 2006
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhiko Kitamura, Yasuhiro Oki, Tetsuya Aoyama, Kyoichi Oka, Nobuo Uotani, Hiroshi Takahashi, Yuji Ito
  • Patent number: 6852154
    Abstract: The invention provides: an ink set comprising a yellow ink composition, a magenta ink composition, and a cyan ink composition, wherein the magenta ink composition contains as a colorant at least one member selected from compounds represented by the following formula (1) and salts thereof; and an ink set comprising two magenta ink compositions differing in color density, wherein the magenta ink composition having a lower color density contains as a colorant at least one member selected from compounds represented by the following formula (1) and salts thereof. Also disclosed are: an ink cartridge housing the ink set; a process for recording with the ink set; and recorded matter obtained by recording with the ink set.
    Type: Grant
    Filed: April 21, 2003
    Date of Patent: February 8, 2005
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhiko Kitamura, Hiroko Hayashi, Kyoichi Oka
  • Patent number: 6811597
    Abstract: An ink composition and/or a recording medium are made to contain a compound expressed by general formula (1) and a hydrazide compound. An ink composition thereby obtained does not clog and the ink composition and recording medium thus obtained can offer high quality images that hardly cause yellowing of the resulting recording with superior light resistance. Recording and an inkjet recording method pertaining thereto are also provided.
    Type: Grant
    Filed: March 21, 2002
    Date of Patent: November 2, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Yasuhiro Oki, Kazuhiko Kitamura, Tetsuya Aoyama, Kyoichi Oka, Nobuo Uotani, Hiroshi Takahashi, Yuji Ito
  • Patent number: 6761759
    Abstract: The ink composition of the present invention contains a coloring agent, water, a water-soluble organic solvent which is a liquid at least at temperatures of 40° C. or less, and which has a solubility of 1 wt % or greater with respect to water at a temperature of 20° C., and a saturation vapor pressure of 1.7 Pa or less at a temperature of 20° C. (with said organic solvent being contained in the ink composition at the rate of 10 to 35 wt %), and one or more amidine type compounds. As a result, the present invention provides an ink composition, a recording medium, recorded matter and an ink jet recording method that make it possible to obtain images with a high image quality which are superior in terms of the gas resistance of the recorded matter.
    Type: Grant
    Filed: March 21, 2002
    Date of Patent: July 13, 2004
    Assignee: Seiko Epson Corporation
    Inventors: Yasuhiro Oki, Kazuhiko Kitamura, Tetsuya Aoyama, Kyoichi Oka, Nobuo Uotani, Hiroshi Takahashi, Yuji Ito
  • Publication number: 20040085421
    Abstract: An ink composition and/or a recording medium are made to contain a compound expressed by general formula (1) and a hydrazide compound. An ink composition thereby obtained does not clog and the ink composition and recording medium thus obtained can offer high quality images that hardly cause yellowing of the resulting recording with superior light resistance. Recording and an inkjet recording method pertaining thereto are also provided.
    Type: Application
    Filed: June 24, 2003
    Publication date: May 6, 2004
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Yasuhiro Oki, Kazuhiko Kitamura, Tetsuya Aoyama, Kyoichi Oka, Nobuo Uotani, Hiroshi Takahashi, Yuji Ito
  • Publication number: 20040048745
    Abstract: The invention provides: an ink set comprising a yellow ink composition, a magenta ink composition, and a cyan ink composition, wherein the magenta ink composition contains as a colorant at least one member selected from compounds represented by the following formula (1) and salts thereof; and an ink set comprising two magenta ink compositions differing in color density, wherein the magenta ink composition having a lower color density contains as a colorant at least one member selected from compounds represented by the following formula (1) and salts thereof.
    Type: Application
    Filed: April 21, 2003
    Publication date: March 11, 2004
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kazuhiko Kitamura, Hiroko Hayashi, Kyoichi Oka
  • Publication number: 20040011249
    Abstract: An ink composition and/or a recording medium are made to contain a compound expressed by general formula (1) and a hydrazide compound. An ink composition thereby obtained does not clog and the ink composition and recording medium thus obtained can offer high quality images that hardly cause yellowing of the resulting recording with superior light resistance. Recording and an inkjet recording method pertaining thereto are also provided.
    Type: Application
    Filed: June 24, 2003
    Publication date: January 22, 2004
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Yasuhiro Oki, Kazuhiko Kitamura, Tetsuya Aoyama, Kyoichi Oka, Nobuo Uotani, Hiroshi Takahashi, Yuji Ito
  • Publication number: 20030070582
    Abstract: A compound expressed by General Formula 1, whose weight reduction after 1 hour at 60° C. is no more than 1%, is contained in an ink composition and/or a recording medium. This makes it possible to provide an ink composition, a recording medium, printed matter, and an ink jet recording method with which the light resistance of the printed matter is excellent, there is no ink clogging, and a high-quality image with almost no yellowing of the printed matter can be obtained.
    Type: Application
    Filed: March 21, 2002
    Publication date: April 17, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kazuhiko Kitamura, Yasuhiro Oki, Tetsuya Aoyama, Kyoichi Oka, Nobuo Uotani, Hiroshi Takahashi, Yuji Ito
  • Patent number: 6514330
    Abstract: Disclosed is an ink composition for ink jet recording which is free from precipitation and can realize, on a high level, various properties required of ink compositions for ink jet recording. In a copper complex colorant-containing ink for ink jet recording, the free copper ion concentration of the ink composition is brought to not more than 10 ppm. Preferably, ethylenediaminetetraacetic acid or a salt thereof is used to bring the free copper ion concentration to not more than 10 ppm.
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: February 4, 2003
    Assignee: Seiko Epson Corporation
    Inventors: Miharu Kanaya, Kyoichi Oka, Kazuaki Watanabe
  • Publication number: 20030010253
    Abstract: The ink composition of the present invention contains a coloring agent, water, a water-soluble organic solvent which is a liquid at least at temperatures of 40° C. or less, and which has a solubility of 1 wt % or greater with respect to water at a temperature of 20° C., and a saturation vapor pressure of 1.7 Pa or less at a temperature of 20° C. (with said organic solvent being contained in the ink composition at the rate of 10 to 35 wt %), and one or more amidine type compounds. As a result, the present invention provides an ink composition, a recording medium, recorded matter and an ink jet recording method that make it possible to obtain images with a high image quality which are superior in terms of the gas resistance of the recorded matter.
    Type: Application
    Filed: March 21, 2002
    Publication date: January 16, 2003
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Yasuhiro Oki, Kazuhiko Kitamura, Tetsuya Aoyama, Kyoichi Oka, Nobuo Uotani, Hiroshi Takahashi, Yuji Ito
  • Publication number: 20020185036
    Abstract: An ink composition and/or a recording medium are made to contain a compound expressed by general formula (1) and a hydrazide compound. An ink composition thereby obtained does not clog and the ink composition and recording medium thus obtained can offer high quality images that hardly cause yellowing of the resulting recording with superior light resistance. Recording and an inkjet recording method pertaining thereto are also provided.
    Type: Application
    Filed: March 21, 2002
    Publication date: December 12, 2002
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Yasuhiro Oki, Kazuhiko Kitamura, Tetsuya Aoyama, Kyoichi Oka, Nobuo Uotani, Hiroshi Takahashi, Yuji Ito