Issued Patents All Time
Showing 1–12 of 12 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 11965102 | Photochromic annelated naphthopyrane systems with special substituents, for attaining rapid lightening speeds | Udo Weigand, Herbert Zinner | 2024-04-23 |
| 10077274 | UV-curing-compatible photochromic fused naphthopyrans | Udo Weigand, Herbert Zinner | 2018-09-18 |
| 9963574 | Photochromic fluorenopyrans with defined dibenzo[B,D]pyrano fused attachment | Udo Weigand, Herbert Zinner | 2018-05-08 |
| 9151872 | Photochromic double-fused naphthopyrans | Udo Weigand, Herbert Zinner | 2015-10-06 |
| 8987477 | Photochromic bis-idenofused naphthopryans | Udo Weigand, Herbert Zinner | 2015-03-24 |
| 8933220 | Photochromic fused naphthopyrans having a benzene ring which is adjacent to the pyran oxygen and is linked to the para substituent via both meta positions | Manfred Melzig, Udo Weigand | 2015-01-13 |
| 8486312 | Photochromic naphthopyrans having a double-bridged terphenyl sub-unit | Manfred Melzig, Udo Weigand | 2013-07-16 |
| 8236716 | Photochromic benzopyrano-benzopyrans with further fusing | Manfred Melzig, Udo Weigand | 2012-08-07 |
| 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 |
| 7544315 | Photochromic h-annellated benzo[f]chromene compounds | Manfred Melzig, Udo Weigand | 2009-06-09 |