Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4844980 | Silica or silicic acid particles whose surface located hydroxyl groups are at least partially replaced by organic groups | Burghard Gruning, Ulrich Holtschmidt, Gotz Koerner | 1989-07-04 |