Issued Patents 1989
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4859206 | Hair dye preparations containing nitrodiphenylamine derivative | Edgar Lieske, Horst Hoeffkes, Norbert Maak | 1989-08-22 |
| 4842612 | Aminophenyl alkylenediamines useful in oxidation hair dyes | Edgar Lieske, Norbert Maak | 1989-06-27 |
| 4838893 | Oxidation hair dyes comprising substituted dihydroxypyridines as coupling components | Norbert Maak, Edgar Lieske | 1989-06-13 |
| 4832697 | Hair dye preparations containing substantive nitrodiphenylamine derivatives | Edgar Lieske, Norbert Maak | 1989-05-23 |