Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4886539 | Method of vacuum refining of glassy materials with selenium foaming agent | Richard L. Gerutti, Robert B. Heithoff, Ronald L. Schwenninger, Wright M. Welton | 1989-12-12 |
| 4798616 | Multi-stage process and apparatus for refining glass or the like | Leonard A. Knavish | 1989-01-17 |