Patents by Inventor Stefan Seiderer

Stefan Seiderer 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).

  • Method of recovering polyvinyl chloride from solvent-containing waste PVC pastes
    Patent number: 5158984
    Abstract: Reuseable polyvinyl chloride is recovered from solvent-loaded waste polyvinyl chloride paste by adding one twentieth of the paste weight of an acyl polyethylene glycol ester, then adding about twice the paste weight of water, while stirring, driving off the solvent by steam distillation, separating the solvent from the resulting two-phase distillate, and filtering off and drying the polyvinyl chloride granules floating in water left behind in the distillation residue.
    Type: Grant
    Filed: March 30, 1992
    Date of Patent: October 27, 1992
    Assignee: Carl Freudenberg
    Inventors: Jorg Hausdorf, Bardo Anselm, Steffen Kosack, Peter Schafer, Rolf Schneider, Stefan Seiderer