Patents by Inventor Chiaki Kasada

Chiaki Kasada 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: 7402375
    Abstract: The present invention provides organic dye compounds having their absorption maxima in a region ranging from the ultraviolet region to a relatively short wavelength visible region and uses thereof. The present invention provides specific monomethine cyanine dyes, light absorbents and optical recording media comprising the monomethine cyanine dyes, and a process for producing the monomethine cyanine dyes which comprises a step of reacting a quaternary ammonium salt of nitrogen atom-containing heterocyclic compound having a reactive methyl group with a quaternary ammonium salt of nitrogen atom-containing heterocyclic compound having an appropriate leaving group.
    Type: Grant
    Filed: May 16, 2003
    Date of Patent: July 22, 2008
    Assignee: Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenkyujo
    Inventors: Chiaki Kasada, Yasushi Aizawa, Toshio Kawata, Shigeo Yasui
  • Patent number: 7354694
    Abstract: The present invention provides styryl dyes which have absorption maxima at a wavelength of 400 nm or less and are sensitive to a laser beam with a wavelength of 450 nm or less, light absorbents and optical recording media which comprise the styryl dyes, and a process for producing the styryl dyes which comprises reacting with an aldehyde compound a quaternary ammonium salt of nitrogen atom containing heterocyclic compound having an active methyl or active methylene group.
    Type: Grant
    Filed: November 24, 2000
    Date of Patent: April 8, 2008
    Assignee: Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenkyuko
    Inventors: Chiaki Kasada, Toshio Kawata, Kentaro Yano, Shigeo Yasui
  • Publication number: 20050240019
    Abstract: The present invention provides styryl dyes which have absorption maxima at a wavelength of 400 nm or less and are sensitive to a laser beam with a wavelength of 450 nm or less, light absorbents and optical recording media which comprise the styryl dyes, and a process for producing the styryl dyes which comprises reacting with an aldehyde compound a quaternary ammonium salt of nitrogen atom containing heterocyclic compound having an active methyl or active methylene group.
    Type: Application
    Filed: April 11, 2005
    Publication date: October 27, 2005
    Applicant: KABAYUSHI KAISHI HAYASHIBARA SEIBUTSU KAGAKU KENKYUJO
    Inventors: Chiaki Kasada, Toshio Kawata, Kentaro Yano, Shigeo Yasui
  • Patent number: 6683188
    Abstract: The present invention provides organic dye compounds having their absorption maxima in a region ranging from the ultraviolet region to a relatively short wavelength visible region and uses thereof. The present invention provides specific monomethine cyanine dyes, light absorbents and optical recording media comprising the monomethine cyanine dyes, and a process for producing the monomethine cyanine dyes which comprises a step of reacting a quaternary ammonium salt of nitrogen atom-containing heterocyclic compound having a reactive methyl group with a quaternary ammonium salt of nitrogen atom-containing heterocyclic compound having an appropriate leaving group.
    Type: Grant
    Filed: August 17, 2001
    Date of Patent: January 27, 2004
    Assignee: Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenkyujo
    Inventors: Chiaki Kasada, Yasushi Aizawa, Toshio Kawata, Shigeo Yasui
  • Publication number: 20030181727
    Abstract: The present invention provides organic dye compounds having their absorption maxima in a region ranging from the ultraviolet region to a relatively short wavelength visible region and uses thereof. The present invention provides specific monomethine cyanine dyes, light absorbents and optical recording media comprising the monomethine cyanine dyes, and a process for producing the monomethine cyanine dyes which comprises a step of reacting a quaternary ammonium salt of nitrogen atom-containing heterocyclic compound having a reactive methyl group with a quarternary ammonium salt of nitrogen atom-containing heterocyclic compound having an appropriate leaving group.
    Type: Application
    Filed: May 16, 2003
    Publication date: September 25, 2003
    Applicant: Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenky
    Inventors: Chiaki Kasada, Yasushi Aizawa, Toshio Kawata, Shigeo Yasui
  • Patent number: 6525181
    Abstract: The object of the present invention is to provide organic dye compounds which exert satisfactory optical absorption properties and thermal resistance when used in high density optical recording media. The above object is solved by specific trimethine cyanine dyes, light absorbents and optical recording media which comprise the cyanine dyes, and preparations for the cyanine dyes comprising either reacting a benzoindolium compound having a compatible leaving group with a pyrazinoimidazolium compound having a reactive methyl group; or reacting a benzoindolium compound having a reactive methyl group with a pyrazinoimidazolium compound having a compatible leaving group.
    Type: Grant
    Filed: October 23, 2001
    Date of Patent: February 25, 2003
    Assignee: Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenkyujo
    Inventors: Chiaki Kasada, Katsumi Orita, Kentaro Yano, Toshio Kawata, Shigeo Yasui
  • Publication number: 20020178517
    Abstract: The object of the present invention is to provide organic dye compounds which exert satisfactory optical absorption properties and thermal resistance when used in high density optical recording media. The above object is solved by specific trimethine cyanine dyes, light absorbents and optical recording media which comprise the cyanine dyes, and preparations for the cyanine dyes comprising either reacting a benzoindolium compound having a compatible leaving group with a pyrazinoimidazolium compound having a reactive methyl group; or reacting a benzoindolium compound having a reactive methyl group with a pyrazinoimidazolium compound having a compatible leaving group.
    Type: Application
    Filed: October 23, 2001
    Publication date: December 5, 2002
    Inventors: Chiaki Kasada, Katsumi Orita, Kentaro Yano, Toshio Kawata, Shigeo Yasui
  • Patent number: 6413607
    Abstract: The present invention provides organic dye compounds which exert excellent recording characteristics in high-density optical recording media, and uses thereof. The present invention solves the objects of the present invention by providing non-symmetric trimethine cyanine dyes having a specific structure and properties, light absorbents and optical recording media comprising the cyanine dyes, and a process for preparing the cyanine dye comprising a step of reacting either 3,3-dimethyl-5-nitroindolium compounds or 3,3-dimethyl-5-sulfonamideindolium compounds, which have a reactive methyl group or an appropriate leaving group, with 3,3-dimethylbezoindolium compounds, which have a reactive methyl group or an appropriate leaving group.
    Type: Grant
    Filed: December 5, 2000
    Date of Patent: July 2, 2002
    Assignee: Kabushiki Kaisha Hayashibara Seibutsu Kagaku Kenkyujo
    Inventors: Chiaki Kasada, Yoshie Hata, Toshio Kawata, Shigeo Yasui
  • Publication number: 20020028918
    Abstract: Disclosed are novel styryl dyes, and light absorbents, light-resistant improvers, and optical recording media, which comprise the styryl dyes. The styryl dyes exert satisfactory solubilities and relatively-high light resistance when used in high-density optical recording media.
    Type: Application
    Filed: July 5, 2001
    Publication date: March 7, 2002
    Applicant: KABUSHIKI KAISHA HAYASHIBARA SEIBUTSU KAGAKU KENKYUJO
    Inventors: Chiaki Kasada, Yoshinori Koyama, Toshio Kawata, Shigeo Yasui