Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5322581 | Join in the overlapped zone of needle punched bentonite sealing sheets | Georg Heerten | 1994-06-21 |
| 5221568 | Water and/or oil-permeable sealing mat consisting substantially of a substrate layer, a layer of swellable clay and a cover layer | Georg Heerten, Karsten Johannssen | 1993-06-22 |