Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6177578 | Processless diacetylenic salt films capable of developing a black image | David F. Lewis | 2001-01-23 |
| 5731112 | Processless diacetylenic salt films capable of developing a black image | David F. Lewis | 1998-03-24 |