Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4867890 | Lubricating oil compositions containing ashless dispersant, zinc dihydrocarbyldithiophosphate, metal detergent and a copper compound | Frederick A. Gibson, John F. Marsh | 1989-09-19 |
| 4859353 | Sulphur-containing borate esters | — | 1989-08-22 |