Issued Patents 2011
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8013174 | Photochromic spirodihydrophenanthropyrans | Udo Weigand, Manfred Melzig | 2011-09-06 |
| 7922941 | Photochromic plastic object | Udo Weigand, Manfred Melzig | 2011-04-12 |
| 7892296 | Photochromic benzopyrans | Manfred Melzig, Udo Weigand | 2011-02-22 |