Issued Patents 1982
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4360459 | Sulphur dyestuffs of the carbazole series | Steffen Piesch | 1982-11-23 |
| 4320060 | Process for the preparation of derivatives of 3-(4-hydroxy-anilino)carbazole | Steffen Piesch, Friedrich Engelhardt, Herbert Wille, Artur Meyer | 1982-03-16 |
| 4309178 | Process for isolating sulphur dyestuffs from aqueous crude melts containing sodium polysulphide | Georg Daniek, Artur Meyer | 1982-01-05 |