Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4879181 | Sintered spherical pellets containing clay as a major component useful for gas and oil well proppants | — | 1989-11-07 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4879181 | Sintered spherical pellets containing clay as a major component useful for gas and oil well proppants | — | 1989-11-07 |