Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4888128 | Paper-coating slips containing fluorescent brighteners | Jochen Koll, Werner Bieber, Joachim Konig, Udo Eckstein, Hans Theidel | 1989-12-19 |
| 4877328 | Internal mixer | Klaus Ruthenberg | 1989-10-31 |