Issued Patents 1989
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4855343 | Paper size based on finely divided aqueous dispersions | Fritz Reichel, Ulrich Riebeling, Lothar Hoehr | 1989-08-08 |
| 4835212 | Sizing agents for paper based on finely divided aqueous dispersions | Fritz Reichel, Ulrich Riebeling, Lothar Hoehr | 1989-05-30 |
| 4818341 | Production of paper and paperboard of high dry strength | Sigberg Pfohl, Volkmar Weberndoerfer, Gerd Rehmer, Michael Kroener, Andreas Stange | 1989-04-04 |
| 4804387 | Liquid black dye mixture | Rudolf Bermes, Sigberg Pfohl | 1989-02-14 |