Patent US2667481A successfully refreshed from Google Patents.
US2667481A
Expired / Lapsed
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Process for making water-soluble hydroxyalkyl cellulose ethers
Assignee: Akzo Nobel UK PLC
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Filing: 1949-07-28
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Granted: 1954-01-26
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Expires: 1969-07-28
Abstract
No abstract record available.
Inventors
- 👤 Clinton W Tasker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:14
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/02; C08B11/04; C08B11/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
107 words
A PROCESS FOR PRODUCING A WATER-SOLUBLE HYDROXYALKYL CELLULOSE COMPRISING REACTING A MASS CONSISTING OF A SUBSTANTIALLY ANHYDROUS ALKALISOLUBLE, WATER-INSOLUBLE HYDROXYALKYL CELLULOSE HAVING BETWEEN 0.1 AND 0.5 ALKYLENE OXIDE GROUPS PER GLUCOSE UNIT AND AN ALKYLENE OXIDE ETHERIFYING AGENT AT 80-110* C. UNDER PRESSURE UNTIL A SUBSTITUTION OF 2 TO ALKYLENE OXIDE GROUPS PER GLUCOSE UNIT IS ATTAINED, SAID WATER-INSOLUBLE CELLULOSE ETHER BEING SELECTED FROM THE GROUP CONSISTING OF THOSE DERIVED FROM THE REACTION OF CELLULOSE WITH A COMPOUND SELECTED FROM THE GROUP CONSISTING OF ETHYLENE OXIDE, PROPYLENE OXIDE, AND GLYCIDE, AND THE ETHERIFYING AGENT BEING SELECTED FROM THE GROUP CONSISTING OF ETHYLENE OXIDE, PROPYLENE OXIDE, AND GLYCIDE.
Claim 2
Dependent Claim
107 words
A PROCESS FOR PRODUCING A WATER-SOLUBLE HYDROXYALKYL CELLULOSE COMPRISING REACTING A MASS CONSISTING OF A SUBSTANTIALLY ANHYDROUS ALKALISOLUBLE, WATER-INSOLUBLE HYDROXYALKYL CELLULOSE HAVING BETWEEN 0.1 AND 0.5 ALKYLENE OXIDE GROUPS PER GLUCOSE UNIT AND AN ALKYLENE OXIDE ETHERIFYING AGENT AT 80-110* C. UNDER PRESSURE UNTIL A SUBSTITUTION OF 2 TO ALKYLENE OXIDE GROUPS PER GLUCOSE UNIT IS ATTAINED, SAID WATER-INSOLUBLE CELLULOSE ETHER BEING SELECTED FROM THE GROUP CONSISTING OF THOSE DERIVED FROM THE REACTION OF CELLULOSE WITH A COMPOUND SELECTED FROM THE GROUP CONSISTING OF ETHYLENE OXIDE, PROPYLENE OXIDE, AND GLYCIDE, AND THE ETHERIFYING AGENT BEING SELECTED FROM THE GROUP CONSISTING OF ETHYLENE OXIDE, PROPYLENE OXIDE, AND GLYCIDE.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-01-25 | 1957-07-27 | 1958-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-01-25 | 1961-07-27 | 1962-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-01-25 | 1965-07-27 | 1966-01-26 | $7700.00 | Window Closed / Lapsed |