Issued Patents All Time
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5023059 | Recovery of metal values and hydrofluoric acid from tantalum and columbium waste sludge | Karl A. Romberger, Bart F. Bakke, Martin A. Hobin, Charles R. Clark | 1991-06-11 |
| 4663130 | Process for dissolving tantalum/columbium materials containing alkali metal impurities | Roger M. Bergman, Brian J. Higgins, Karl A. Romberger | 1987-05-05 |
| 4592904 | Process for producing columbium oxyfluoride | C. Edward Mosheim, Umedray L. Sheth | 1986-06-03 |
| 4420469 | Pyrohydrolysis of columbium oxyfluoride to columbium oxide | Roger M. Bergman, Charles R. Nippert, Jr. | 1983-12-13 |