Patents by Inventor Toshifumi Kawamura

Toshifumi Kawamura 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 pitch for matrix
    Patent number: 5292473
    Abstract: A process for preparing pitch for matrix wherein an optically isotropic pitch is formed into a fibrous pitch, and the fibrous pitch thus obtained is nitrated with a nitration reagent in the presence of an acid catalyst. The resulting pitch can be carbonized with a low energy, is high in carbonization yield, low in softening point and excellent in moldability and impregnability.
    Type: Grant
    Filed: January 27, 1993
    Date of Patent: March 8, 1994
    Assignee: Petoca, Ltd.
    Inventors: Takashi Maeda, Toshifumi Kawamura