US2816889A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the preparation of high gel carboxyalkylated cellulose ethers
Assignee: EIDP Inc
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Filing: 1954-10-01
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Granted: 1957-12-17
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Expires: 1974-10-01
Abstract
No abstract record available.
Inventors
- 👤 Wiley M Branan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:19
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
135 words
A PROCESS FOR THE PREPARATION OF A PARTIALLY, BUT INCOMPLETELY, WATER-SOLUBLE ALKALI METAL SALT OF A CELLULOSE ETHER SELECTED FROM THE CLASS CONSISTING OF CARBOXYMETHYL CELLULOSE AND CARBOXYETHYL CELLULOSE, THE NON-SOLUBLE PROPORTION OF WHICH EXISTS AS AN INSOLUBLE GEL IN THE PRESENCE OF WATE, INCLUDING THE ESSENTIAL STEP OF MIXING CELLULOSE IN THE FORM OF SHREDDED, FIBRILLATED WOOD PULP WITH ABOUT 0.5 TO 0.9 MOLE PER ANHYDROGLUCOSE UNIT OF CELLULOSE OF AN ETHERIFYING AGENT SELECTED FROM THE GROUP CONSISTING OF THE SHORT-CHAIN, MONO-CHLORINATED, MONOCARBOXYLIC, SATURATED FATTY ACIDS AND THE ALKALI METAL SATLS THEREOF IN THE PRESENCE OF AN AQUEOUS ALKALI METAL HYDROXIDE AND IN A REACTION MEDIUM HAVING A LIQUID TO CELLULOSE RATIO NOT LARGER THAN ABOUT 2.1, THE FIRBERS OF SAID WOOD PULP HAVING AN AVERAGE FIBER LENGTH OF AT LEAST ABOUT 0.3 MM.
Claim 2
Dependent Claim
135 words
A PROCESS FOR THE PREPARATION OF A PARTIALLY, BUT INCOMPLETELY, WATER-SOLUBLE ALKALI METAL SALT OF A CELLULOSE ETHER SELECTED FROM THE CLASS CONSISTING OF CARBOXYMETHYL CELLULOSE AND CARBOXYETHYL CELLULOSE, THE NON-SOLUBLE PROPORTION OF WHICH EXISTS AS AN INSOLUBLE GEL IN THE PRESENCE OF WATE, INCLUDING THE ESSENTIAL STEP OF MIXING CELLULOSE IN THE FORM OF SHREDDED, FIBRILLATED WOOD PULP WITH ABOUT 0.5 TO 0.9 MOLE PER ANHYDROGLUCOSE UNIT OF CELLULOSE OF AN ETHERIFYING AGENT SELECTED FROM THE GROUP CONSISTING OF THE SHORT-CHAIN, MONO-CHLORINATED, MONOCARBOXYLIC, SATURATED FATTY ACIDS AND THE ALKALI METAL SATLS THEREOF IN THE PRESENCE OF AN AQUEOUS ALKALI METAL HYDROXIDE AND IN A REACTION MEDIUM HAVING A LIQUID TO CELLULOSE RATIO NOT LARGER THAN ABOUT 2.1, THE FIRBERS OF SAID WOOD PULP HAVING AN AVERAGE FIBER LENGTH OF AT LEAST ABOUT 0.3 MM.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-12-16 | 1961-06-17 | 1961-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-12-16 | 1965-06-17 | 1965-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-12-16 | 1969-06-17 | 1969-12-17 | $7700.00 | Window Closed / Lapsed |