Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4851047 | Process for preparing water-repellent articles from gypsum powder containing hydrophobic agents | Ulrich Demlehner, Herbert Eck, Erich Pilzweger, Otto Zeller | 1989-07-25 |