Issued Patents 1989
Showing 1–6 of 6 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4869989 | Dry toners containing fanal pigments based on cationic dyes | Hubertus Psaar | 1989-09-26 |
| 4849306 | Dry toners containing methinefanal pigments | Hubertus Psaar, Horst Berneth | 1989-07-18 |
| 4847177 | Fanal pigments of closed-ring dry toners containing indamine-and diphenylmethane dyestuffs | Hubertus Psaar | 1989-07-11 |
| 4841052 | Naphthalic acid imides electrophotographic toners | Horst Harnisch | 1989-06-20 |
| 4812379 | Electrophotographic toners containing an additive reinforcing the cationic charge | Horst Harnisch | 1989-03-14 |
| 4808719 | 1H-imidazo[2,3-a]indol-2-ones as color-forming agents | Hubertus Psaar | 1989-02-28 |