Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4853085 | Neutral sized paper for use in the production of gypsum wallboard | John Kehoe | 1989-08-01 |
| 4801355 | Tabular acicular gypsum and method of filling paper | John C. Gaynor, Robert Erickson | 1989-01-31 |