Patents by Inventor Koji Kunimoto

Koji Kunimoto 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).

  • Tetrabromobisphenol A having a large particle size and process for its production
    Patent number: 5302761
    Abstract: Single crystals of tetrabromobisphenol A having an average particle size of from 150 to 500 .mu.m, each having a polyhedral shape.
    Type: Grant
    Filed: May 19, 1993
    Date of Patent: April 12, 1994
    Assignee: Tosoh Corporation
    Inventors: Hanzo Tamabayashi, Shinji Kakimoto, Tetsuto Mizui, Akihiko Nomura, Koji Kunimoto
  • Process for producing tetrabromobisphenol A
    Patent number: 5138103
    Abstract: A process for producing tetrabromobisphenol A of high quality, which comprises brominating bisphenol A with bromine, wherein a solvent mixture comprising a hydrohalogenic acid and an alcohol, is used as the solvent for reaction. Also disclosed is a process for producing tetrabromobisphenol A of high quality, which comprises brominating bisphenol A with bromine in an alcohol, wherein the reaction temperature is set at a level of from -10.degree. to +20.degree. C., and water is added in an aging step.
    Type: Grant
    Filed: August 16, 1991
    Date of Patent: August 11, 1992
    Assignee: Tosoh Corporation
    Inventors: Hisao Eguchi, Masashige Kubo, Noritaka Nagasaki, Koji Kunimoto
  • Process for producing tetrabromobisphenol A
    Patent number: 5059726
    Abstract: A process for producing tetrabromobisphenol A, which comprises brominating bisphenol A in methanol, wherein the substrate concentration of bisphenol A to methanol is at most 20 wt/vol %.
    Type: Grant
    Filed: October 22, 1990
    Date of Patent: October 22, 1991
    Assignee: Tosoh Corporation
    Inventors: Hisao Eguchi, Masashige Kubo, Koji Kunimoto, Sadami Shimizu, Masakatsu Sato, Hanzo Tamabayashi
  • Process for producing tetrabromobisphenol A
    Patent number: 5008469
    Abstract: A process for producing tetrabromobisphenol A, which comprises brominating bisphenol A in methanol, wherein the substrate concentration of bisphenol A to methanol is at most 20 wt/vol %.
    Type: Grant
    Filed: January 25, 1990
    Date of Patent: April 16, 1991
    Assignee: Tosoh Corporation
    Inventors: Hisao Eguchi, Masashige Kubo, Koji Kunimoto, Sadami Shimizu, Masakatsu Sato, Hanzo Tamabayashi