Patents by Inventor Norbert Seifried

Norbert Seifried 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).

  • Process for the recovery of pure hellebrin
    Patent number: 4435563
    Abstract: There is provided a process for the recovery of pure hellebrin which comprises extracting a defatted hellebrin extract dissolved in a water-alkanol mixture or water-acetone mixture with a mixture of a lower alkanol or acetone and di-, tri-, or tetrachloromethane (or dichloroethane) evaporating the extraction agent in a vacuum and then heating with ethanol until the deposition of the first hellebrin crystals begins.
    Type: Grant
    Filed: May 11, 1982
    Date of Patent: March 6, 1984
    Assignee: Degussa Aktiengesellschaft
    Inventors: Gerhard Oepen, Karl-Heinz Mangartz, Norbert Seifried, Jurgen Engel, Otto Isaac