Issued Patents All Time
Showing 1–10 of 10 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5147964 | Method for reducing fluid loss from oilfield cement slurries using vinyl grafted wattle tannin | David A. Huddleston, Robert K. Gabel | 1992-09-15 |
| 5134215 | Method for reducing fluid loss from oilfield cement slurries using vinyl grafted wattle tannin | David A. Huddleston, Robert K. Gabel | 1992-07-28 |
| RE33856 | Terpolymer compositions for aqueous drilling fluids | David M. Giddings | 1992-03-24 |
| RE33855 | Terpolymer composition for aqueous drilling fluids | David M. Giddings | 1992-03-24 |
| 5032297 | Enzymatically degradable fluid loss additive | Stephan J. Allenson, Robert K. Gabel, David A. Huddleston | 1991-07-16 |
| 5028271 | Vinyl grafted lignite fluid loss additives | David A. Huddleston | 1991-07-02 |
| 5009267 | Method for temporarily reducing permeability of subterranean formations | Stephan J. Allenson, Robert K. Gabel | 1991-04-23 |
| 4997581 | Additive and method for temporarily reducing permeability of subterranean formations | Stephan J. Allenson, Robert K. Gabel | 1991-03-05 |
| 4938803 | Vinyl grafted lignite fluid loss additives | David A. Huddleston | 1990-07-03 |
| 4678591 | Terpolymer composition for aqueous drilling fluids | David M. Giddings | 1987-07-07 |