Patents by Inventor Hans R. Keller

Hans R. Keller 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).

  • Membranes having improved selectivity and recovery, and process for making same
    Patent number: 5409524
    Abstract: The invention is a process for obtaining membranes having improved selectivity and recovery using a combination of heat treating and UV irradiation.
    Type: Grant
    Filed: September 10, 1993
    Date of Patent: April 25, 1995
    Assignee: The Dow Chemical Company
    Inventors: John A. Jensvold, Srikanth R. Chary, Wendy S. Jacks, Hans R. Keller, Theodore L. Parker, Damoder Reddy
  • Loading tool
    Patent number: 4722128
    Abstract: A hand tool for loading an easily damaged resilient elongated object having a generally planar end into a closely fitting relatively rigid casing of conforming shape including a lever member, an elongated tension member with a member for engaging the end of the casing, a resilient compression member for placement against a planar end of the object to be moved and a universal pivot member joining the end of the lever member and the compression member for moving the object in a linear path into the pressure casing without injuring the object being moved.
    Type: Grant
    Filed: August 8, 1986
    Date of Patent: February 2, 1988
    Assignee: The Dow Chemical Company
    Inventor: Hans R. Keller