Patents by Inventor Rene Stepanek

Rene Stepanek 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).

  • Crosslinked polyurethane-polyurea powders, a process for their production and their use as fillers in two-component polyurethane coating compositions
    Patent number: 5021520
    Abstract: The present invention relates to crosslinked polyurethane-polyurea powders which are prepared by a process which comprises dispersing NCO semiprepolymers in an aqueous medium, forming powders and isolating the powders from the aqueous medium, the NCO semiprepolymers having an NCO content of 10 to 20%, being liquid at room temperature and/or dissolved in isocyanate-inert, water-soluble solvents and based on the reaction product of(a) a polyisocyanate component based on at least one organic polyisocyanate with a polyol component having an average hydroxyl functionality of 2.3 to 4.0 and containing(b) a hydrophobic polyol component containing less than 25% by weight of ethylene oxide units, --CH.sub.2 --CH.sub.
    Type: Grant
    Filed: March 19, 1990
    Date of Patent: June 4, 1991
    Assignee: Bayer Aktiengesellschaft
    Inventors: Helmut Reiff, Dieter Dieterich, Rene Stepanek