Patents by Inventor Hans J. De Witte

Hans J. De Witte 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).

  • Iron oxide pigment suspensions and slurries
    Patent number: 4741781
    Abstract: Iron oxide slurries and suspensions are made from water, iron oxide pigments and a dispersing agent which is water soluble salt of citric acid or tartaric acid. The preferred dispersing agents are the ammonium, sodium and potassium salts of citric acid and tartaric acid. The sodium salts of citric acid are particularly preferred. A known additive such as a fungicide may be included. To keep the slurries and suspension from settling, stabilizing agents may also be included.
    Type: Grant
    Filed: October 29, 1986
    Date of Patent: May 3, 1988
    Assignee: Mobay Corporation
    Inventor: Hans J. De Witte