Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4871423 | Enhanced dithionite bleaching | James C. Robinson, Mark Schroeder | 1989-10-03 |
| 4863564 | Method of bleaching high yield pulp by using dithionite ion and excluding oxygen | James C. Robinson, Mark Schroeder | 1989-09-05 |