Issued Patents All Time
Showing 1–9 of 9 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4743683 | Imidazole azo dyes | — | 1988-05-10 |
| 4732997 | Dibenzoxaphosphorin compounds | David G. Leppard | 1988-03-22 |
| 4661437 | Photographic material with heterocylic azo dye for the silver dye bleach process | — | 1987-04-28 |
| 4661440 | Process for stabilizing photographic material containing magenta coupler | David G. Leppard | 1987-04-28 |
| 4324898 | Heterocyclic compounds useful as color photographic material | — | 1982-04-13 |
| 4268591 | Material for color photography | — | 1981-05-19 |
| 4268592 | Material for color photography | — | 1981-05-19 |
| 4229577 | Yellow photographic color couplers containing 3-imino-1,3,4-thiadiazolyl-4 groups | Graham Evans, Mario Fryberg, Thomas Stauner, David G. Leppard | 1980-10-21 |
| 4206278 | Color photographic material | — | 1980-06-03 |