Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4888120 | Water-based drilling and well-servicing fluids with swellable, synthetic layer silicates | Heinz Mueller, Claus-Peter Herold, Stephan van Tapavizca, Hans Dolhaine, Winfried Wichelhaus | 1989-12-19 |
| 4839066 | Fabric-softening detergent | Horst Upadek, Winfried Wichelhaus | 1989-06-13 |
| 4814070 | Alkyl sulfosuccinates based on alkoxylated fatty alcohols as collectors for non-sulfidic ores | Rita Koester, Uwe Ploog | 1989-03-21 |