Patents by Inventor Cheng-Kuo Hsaio

Cheng-Kuo Hsaio 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).

  • Processes for the preparation of phthalocyanines for electrophotography
    Patent number: 5100752
    Abstract: A process for the preparation of x-metal free phthalocyanine which comprises (i) initially preparing a mixture of alpha- and x-metal free phthalocyanines from alpha-phthalocyanine with a grinding or mixing device, (ii) converting the above mixture to x-metal free phthalocyanine by the addition of an organic solvent, (iii) separating the x-metal free phthalocyanine therefrom, and thereafter washing the x-metal free phthalocyanine with a basic solution.
    Type: Grant
    Filed: May 7, 1990
    Date of Patent: March 31, 1992
    Assignee: Xerox Corporation
    Inventors: Cheng-Kuo Hsaio, Ah-Mee Hor, Giuseppa Baranyi, Terry L. Bluhm, James F. Duff, George Liebermann, Eric B. Wasmund