Patents by Inventor Kazuyuki Nobuoka

Kazuyuki Nobuoka 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).

  • Process for preparing dinitroanthraquinones
    Patent number: 4076734
    Abstract: A process for preparing 1,5- and 1,8-dinitroanthraquinones having high purity by reacting anthraquinone and nitric acid and sulfuric acid, sulfuric acid being used in an amount of less than that of said nitric acid, and a method of separating the resulting 1,5-and 1,8-dinitroanthraquinone mixture into each component by using nitrobenzene and/or nitrotoluene.
    Type: Grant
    Filed: October 4, 1972
    Date of Patent: February 28, 1978
    Assignee: Sumitomo Chemical Company, Limited
    Inventors: Eiji Yamada, Mutuo Yamada, Kazuyuki Nobuoka