Patents by Inventor Gerhard Greber, deceased

Gerhard Greber, deceased 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).

  • Heat-stable polyimides and polyamide-imides with modified benzhydrol structural elements and their preparation
    Patent number: 5378799
    Abstract: Heat-stable polyimides and polyamideimides with modified benzhydrol structural elements and a process of preparing thereof; wherein the polyimides and polyamideimides are obtained by reacting 3,3'4,4'-benzhydroltetracarboxylic acid dimethyl ester a) with only a diamine and then cyclized to give polyimides or b) with a diamine and with trimellitic, phthalic-or isophthalic acid (or the anhydrides, acid chlorides, anhydride chlorides or esters) and is then cyclized to give polyamideimides.
    Type: Grant
    Filed: September 13, 1993
    Date of Patent: January 3, 1995
    Assignee: Chemie Linz GmbH
    Inventors: Gerhard Greber, deceased, Heinrich Gruber, Marcel Sychra