Issued Patents 1997
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5674476 | Process for making a persulfate-containing granulate for decolorizing or bleaching hair | Thomas Clausen, Volker Port, Jolanthe Kujawa | 1997-10-07 |
| 5663366 | Process for the synthesis of 4,5-diaminopyrazole derivatives useful for dyeing hair | Hans Neunhoeffer, Stefan Gerstung, Thomas Clausen | 1997-09-02 |
| 5645610 | Substituted 2-alkylamino-4-amino-1-alkylbenzene compounds and oxidation hair dye compositions based on said compounds | Anke Frank, Alexa Weinges | 1997-07-08 |
| 5637115 | Oxidation hair dye compositions containing developers, couplers, and AZO dyes | Hans-Juergen Braun | 1997-06-10 |