Issued Patents 1997
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5651793 | Hydrogen peroxide preparations containing foam regulators | Horst Hoeffkes, Karin Nelles | 1997-07-29 |
| 5609650 | Dyeing of keratin fibres with indolines using metal salts as catalysts | Georg Knuebel, Horst Hoeffkes, Edgar Lieske | 1997-03-11 |