Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4867844 | Method for treating paper to improve the holdout characteristics of printing inks | — | 1989-09-19 |
| 4857110 | Agent for improving the printability of paper and board | Helmut Berenbold | 1989-08-15 |