Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6183634 | Separator | Walters Francois Du Toit | 2001-02-06 |
| 5039361 | Process of phosphating metal surfaces | Dieter Hauffe, Jorg Hieke, Gunter Siemund, Han-Yong Oei | 1991-08-13 |
| 4824490 | Process of producing phosphate coatings on metals | Han-Yong Oei, Gunter Siemund | 1989-04-25 |