Patents by Inventor Reinhard J. Oswald

Reinhard J. Oswald 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).

  • Water-soluble copolymers and their use for exploration and production of petroleum and natural gas
    Patent number: 6395853
    Abstract: The invention relates to copolymers comprising a) 5-95% by weight of structural units which are derived from compounds of the formula 1 b) from 1 to 95% by weight of structural units which are derived from compounds of the formula 2  and c1) from 1 to 95% by weight of structural units which are derived from compounds of the formula 3  or, alternatively, to c1), c2) from 1 to 95% by weight of structural units which are derived from compounds of the formula 4  n which X is a cation. The copolymers according to the invention are suitable as a fluid loss additive for water-based drilling muds and for cement slurries in deep wells, for completion and clearing-out liquids and for water shut-off in production probes.
    Type: Grant
    Filed: June 8, 2000
    Date of Patent: May 28, 2002
    Assignee: Clariant GmbH
    Inventors: Reinhard J. Oswald, Roman Morschhäuser, Karl Heinz Heier, Aranka Tardi, Juergen Tonhauser, Christoph Kayser, Dan Patterson