Issued Patents 1989
Showing 1–4 of 4 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4885141 | Water treatment in aqueous heat transfer apparatus | Alan Gray | 1989-12-05 |
| 4866097 | Controlled release system | Cyril F. Drake | 1989-09-12 |
| 4851225 | Material dispensers | Cyril F. Drake | 1989-07-25 |
| 4849001 | Method for making sintered glass | Cyril F. Drake, Mary Tripp | 1989-07-18 |