Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4481272 | Layered electrophotographic recording medium comprising heterocyclic nitrogen containing organic dye compounds | Albrecht Eckell, Heinz Eilingsfeld, Albert Elzer, Gerhard Hoffmann, Reinhold J. Leyrer +1 more | 1984-11-06 |
| 4353833 | Cationic dyes | Horst Bruder, Hans-Juergen Degen, Klaus Grychtol, Udo Mayer | 1982-10-12 |
| 4336201 | Preparation of electrically conductive carotenoids | Herbert Naarmann, Joachim Paust, Klaus Penzien | 1982-06-22 |
| 4272243 | Dyeing of grain leather | Dietrich Lach, Rolf Streicher | 1981-06-09 |
| 4256458 | Methine dyes for paper and amonically-modified fibers | Hans-Juergen Degen, Klaus Grychtol | 1981-03-17 |
| 4223144 | Triphenylmethane dyes | Hellmut Kast, Klaus Grychtol | 1980-09-16 |