US2517577A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of carboxyalkyl ethers of cellulose
Assignee: Hercules Powder Co
•
Filing: 1946-12-10
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Granted: 1950-08-08
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Expires: 1966-12-10
Abstract
No abstract record available.
Inventors
- 👤 Eugene D Klug
- 👤 John S Tinsley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 02:15
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/02; C08B11/04; C08B11/10; C08B11/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
90 words
IN A PROCESS IN WHICH CELLULOSE IS REACTED IN THE PRESENCE OF STRONG ALKALI AND WATER WITH A CARBOXYALKYL HALIDE ETHERIFICATION AGENT TO FORM A CELLULOSE CARBOXYALIKYL ETHER, THE IMPROVEMENT WHICH CONSISTS IN CARRYING OUT THE ETHERIFICATION REACTION IN A REACTION MEDIUM COMPRISING ALCOHOL SELECTED FROM THE GROUP CONSISTING OF ISOPROPYL ALCOHOL AND TERT.-BUTYL ALCOHOL IN AN AMOUNT OF AT LEAST 1.5 PARTS FOR EACH PART OF WATER PRESENT IN THE ETHERIFICATION REACTION MIXTURE AND SUFFICIENT TO MAINTAIN THE CELLULOSE ETHER FORMED IN A SOLID, UNDISSOLVED STATE THROUGHOUT THE REACTION.
Claim 2
Dependent Claim
90 words
IN A PROCESS IN WHICH CELLULOSE IS REACTED IN THE PRESENCE OF STRONG ALKALI AND WATER WITH A CARBOXYALKYL HALIDE ETHERIFICATION AGENT TO FORM A CELLULOSE CARBOXYALIKYL ETHER, THE IMPROVEMENT WHICH CONSISTS IN CARRYING OUT THE ETHERIFICATION REACTION IN A REACTION MEDIUM COMPRISING ALCOHOL SELECTED FROM THE GROUP CONSISTING OF ISOPROPYL ALCOHOL AND TERT.-BUTYL ALCOHOL IN AN AMOUNT OF AT LEAST 1.5 PARTS FOR EACH PART OF WATER PRESENT IN THE ETHERIFICATION REACTION MIXTURE AND SUFFICIENT TO MAINTAIN THE CELLULOSE ETHER FORMED IN A SOLID, UNDISSOLVED STATE THROUGHOUT THE REACTION.
References Cited (Backward Citations)
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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) | 1953-08-07 | 1954-02-06 | 1954-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-07 | 1958-02-06 | 1958-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-07 | 1962-02-06 | 1962-08-08 | $7700.00 | Window Closed / Lapsed |