Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5039361 | Process of phosphating metal surfaces | Dieter Hauffe, Jorg Hieke, Rudolf Vey, Gunter Siemund | 1991-08-13 |
| 4824490 | Process of producing phosphate coatings on metals | Gunter Siemund, Rudolf Vey | 1989-04-25 |
| 4416705 | Composition and process for production of phosphate coatings on metal surfaces | Gunter Siemund | 1983-11-22 |
| 4199381 | Preparation of metals for cold forming | Karl-Heinz Nuss, Klaus-Dieter Nittel, Gunter Siemund | 1980-04-22 |