Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4878950 | Bitumen composition | Andrew Halasz, David H. Doolittle | 1989-11-07 |
| 4848057 | Roofing shingles | Peter G. MacDonald, Jayant B. Kandalgaonkar | 1989-07-18 |
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4878950 | Bitumen composition | Andrew Halasz, David H. Doolittle | 1989-11-07 |
| 4848057 | Roofing shingles | Peter G. MacDonald, Jayant B. Kandalgaonkar | 1989-07-18 |