Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4835929 | Laminated roofing hip | William R. Carroll, Bobbie J. Lloyd | 1989-06-06 |
| 4825616 | Roofing shingle | Stanley P. Frankoski, Frederick W. Sieling | 1989-05-02 |
| 4795661 | Process for the manufacture of asphalt shingles | Duane A. Davis, Stanley P. Frankoski, Bruno E. Magnus | 1989-01-03 |