Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6699650 | Photographic couplers having improved image dye light stability | David Clarke, Llewellyn J. Leyshon | 2004-03-02 |
| 6444417 | Photographic element containing cyan dye-forming coupler | David Clarke, Llewellyn J. Leyshon | 2002-09-03 |