Patents by Inventor Ralf Friedricsen

Ralf Friedricsen 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 purifying organic synthesis products
    Patent number: 5565102
    Abstract: The novel process for working up solutions or suspensions of organic synthesis products having a pH value of <3, preferably <1, is carried out with the aid of an asymmetrical, semipermeable membrane composed of cyclic polyureas with repeating structural units of the formula (I) ##STR1## wherein the substituents R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, X and Y and the index n are each as defined in the description.
    Type: Grant
    Filed: November 2, 1994
    Date of Patent: October 15, 1996
    Assignee: Bayer Aktiengesellschaft
    Inventors: Horst Brandt, Karlheinz Hildenbrand, Dietrich Tegtmeyer, Ralf Friedricsen, Wolfgang Zarges