Issued Patents All Time
Showing 51–53 of 53 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4957841 | Specifically influencing the triboelectric effect of azo pigments | Alexander Sieber, Franz Schui, Reinhold Deubel | 1990-09-18 |
| 4786575 | Pigment for electrophotographic recording processes | Alexander Sieber, Helmut Troster | 1988-11-22 |
| 4777105 | Magenta colorant for electrophotographic recording processes | Alexander Sieber, Adolf Kroh | 1988-10-11 |