Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4952677 | Azo colorants for ball point pen and ribbon inks | Floyd G. Spence, Robert J. Allen | 1990-08-28 |
| 4824610 | Colorants for ball-point pen and ribbon inks | Reinhard Sappok, Floyd G. Spence | 1989-04-25 |