Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4840744 | Modified succinimides and lubricating oil compositions containing the same | Robert H. Wollenberg, Timothy R. Erdman | 1989-06-20 |
| 4802893 | Modified Succinimides | Robert H. Wollenberg | 1989-02-07 |
| 4798612 | Modified succinimides (x) | Robert H. Wollenberg | 1989-01-17 |