Issued Patents All Time
Showing 1–5 of 5 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4504383 | Rerefining used oil with borohydride reducing agents | — | 1985-03-12 |
| 4439311 | Rerefining used lubricating oil with hydride reducing agents | — | 1984-03-27 |
| 4399025 | Solvent extraction process for rerefining used lubricating oil | Laird C. Fletcher | 1983-08-16 |
| 4360420 | Distillation and solvent extraction process for rerefining used lubricating oil | Laird C. Fletcher, Harold J. Beard | 1982-11-23 |
| 4302325 | Solvent extraction process for rerefining used lubricating oil | Laird C. Fletcher | 1981-11-24 |