Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6214488 | Polymer electrolyte membrane and process for the production thereof | Freddy Helmer-Metzmann, Frank Osan, Arnold Schneller, Helmut Ritter, Konstantin Ledjeff +1 more | 2001-04-10 |
| 5741408 | Polymer electrolyte membrane for use in fuel cells and electrolysis cells | Freddy Helmer-Metzmann, Frank Osan, Arnold Schneller, Helmut Ritter, Konstantin Ledjeff +1 more | 1998-04-21 |
| 5561202 | Polymer electrolyte membrane, and process for the production thereof | Freddy Helmer-Metzmann, Frank Osan, Arnold Schneller, Helmut Ritter, Konstantin Ledjeff +1 more | 1996-10-01 |
| 5438082 | Polymer electrolyte membrane, and process for the production thereof | Freddy Helmer-Metzmann, Frank Osan, Arnold Schneller, Helmut Ritter, Konstantin Ledjeff +1 more | 1995-08-01 |