Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4874724 | Alkali zinc aluminophosphate glass-ceramics | Joseph E. Pierson, Candace J. Quinn | 1989-10-17 |
| 4814297 | Strengthened glass article and method | Joseph E. Pierson, Stanley D. Stookey | 1989-03-21 |