US3565886A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Phosphorylation of cellulosic material having free hydroxyl groups
Assignee: Canadian Patents and Development Ltd
•
Filing: 1969-09-12
•
Granted: 1971-02-23
•
Expires: 1989-09-12
Abstract
Abstract A METHOD FOR PHOSPHORYLATING CELLULOSIC MATERIAL SUCH AS CELLULOSE AND CELLULOSE DERIVATIVES PARTICULARLY THE ESTERS AND ETHERS BY REACTING THE CELLULOSIC MATERIAL WITH A SOLUTION OF PHOSPHORIS PENTOXIDE IN DIMETHYLFORMAMIDE. PHOSPHORYLATED CELLULOSE DERIVATIVES CONTAINING ABOUT 4 TO ABOUT 10% BY WT. BOUND PHOSPHORUS HAVE BEEN PREPARED.
Inventors
- 👤 Louis-Philippe Clermont
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:43
CPC Classifications
C; C08; C08B; C08B13/00; C08B5/00
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-22 | 1974-08-24 | 1975-02-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-22 | 1978-08-24 | 1979-02-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-22 | 1982-08-24 | 1983-02-23 | $7700.00 | Window Closed / Lapsed |