Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 7401817 | Invisible, machine-detectable security marking, production of the security marking, and security system comprising this security marking | Christoph Muller-Rees, Jurgen Kupfer, Horst Leigeber | 2008-07-22 |
| 6570648 | Machine-detectable security marking with an increased level of proof against forgery, production of the security marking, and security system comprising this security marking | Christoph Muller-Rees, Jurgen Kupfer, Horst Leigeber | 2003-05-27 |
| 6057008 | Process for broadening cholesteric reflection bands of photopolymerizable cholesteric liquid crystals, and optical elements produced by this process | Mechthild Kopf, Franz-Heinrich Kreuzer | 2000-05-02 |