Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4569694 | Solid polyamine-based fluid loss control additives | Donald R. Valk | 1986-02-11 |
| 4482381 | Solid polyamine-based fluid loss control additives | Donald R. Valk | 1984-11-13 |