Patents by Inventor Iwawo Yamamoto

Iwawo Yamamoto 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: 5062990
    Abstract: Octasubstituted tetraphyrazinotetraazaporphrazine and compositions forming an electron acceptable discotic liquid crystal phase are disclosed. Said compounds and the metal complexes are easily soluble in an organic solvent such as chloroform or dichloromethane etc and are insoluble in acetone and alcohols; and therefore a columnar phase by silica gel/dichloromethane, recrystallization from tetra-hydrofuran or refining through solid liquid extraction by acetone is possible. Furthermore, stability in a giant molecular can be expected and a functional membrane can be formed by a solution cast method etc., thereby employing as an electon or photoelectron material or an indication element.
    Type: Grant
    Filed: December 27, 1989
    Date of Patent: November 5, 1991
    Assignees: Eastern Co., Ltd., Iwawo Yamamoto
    Inventors: Iwawo Yamamoto, Kazuchika Ohta