Issued Patents All Time
Showing 51–52 of 52 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4914005 | Photographic element containing a cyan dye forming coupler | Philip T. S. Lau, Ping-Wah Tang | 1990-04-03 |
| 4804620 | Photographic material containing a novel polymeric dye-forming coupler | Ping-Wah Tang, Philip T. S. Lau, Harold I. Machonkin, Tien-Teh Chen | 1989-02-14 |