Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4379808 | Sheet type forming board and formed board products | David A. Hettel | 1983-04-12 |
| 4325899 | Method for heat forming hardboard and other types of forming board | David A. Hettel | 1982-04-20 |