US2831852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water-soluble thermoplastic cellulose ethers
Assignee: Dow Chemical Co
•
Filing: 1954-05-27
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Granted: 1958-04-22
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Expires: 1974-05-27
Abstract
No abstract record available.
Inventors
- 👤 Albert B Savage
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 01:02
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/193
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
130 words
THE PROCESS WHICH COMPRISES SUBJECTING AN ALKALI CELLULOSE INITIALLY HAVING AN ALKALI TO CELLULOSE RATIO OF FROM 0.7 TO 1.5 AND PREPARED BY TREATING CELLOUSE WITH A 30 TO 60 PERCENT AQUOUS ALKALI HYDROXIDE SOLUTION TO THE ACTION OF AN OLEFINE OXIDE FROM THE GROUP CONSISTING OF ETHYLENE OXIDE AND PROPYLENE OXIDE, IN AMOUNT MOLECULARLY EQUIVALENT TO FORM 0.45 TO 0.80 PART BY WEIGHT OF PROPYLENE OXIDE PER PART OF CELLULOSE AT A TEMPERAURE NOT IN EXCESS FO 40*C. UNTIL THE OLEFINE OXIDE IS SUBSTANTIALLY FULLY REACTED, AND TO THE ACTION OF FROM 1.1 TO 2.0 PARTS OF METHYL CHLORIDE PER PART OF CELLULOSE AT A TEMPERATURE FROM 40*C. TO 80*C. UNTIL THE ETHERIFICATION IS SUBSTANTIALLY COMPLETE, TO PRODUCE A HYDROXYALKYL METHYL CELLULOSE WHICH IS BOTH COLD WATER-SOLUBLE AND THEROMPLASTIC.
Claim 2
Dependent Claim
130 words
THE PROCESS WHICH COMPRISES SUBJECTING AN ALKALI CELLULOSE INITIALLY HAVING AN ALKALI TO CELLULOSE RATIO OF FROM 0.7 TO 1.5 AND PREPARED BY TREATING CELLOUSE WITH A 30 TO 60 PERCENT AQUOUS ALKALI HYDROXIDE SOLUTION TO THE ACTION OF AN OLEFINE OXIDE FROM THE GROUP CONSISTING OF ETHYLENE OXIDE AND PROPYLENE OXIDE, IN AMOUNT MOLECULARLY EQUIVALENT TO FORM 0.45 TO 0.80 PART BY WEIGHT OF PROPYLENE OXIDE PER PART OF CELLULOSE AT A TEMPERAURE NOT IN EXCESS FO 40*C. UNTIL THE OLEFINE OXIDE IS SUBSTANTIALLY FULLY REACTED, AND TO THE ACTION OF FROM 1.1 TO 2.0 PARTS OF METHYL CHLORIDE PER PART OF CELLULOSE AT A TEMPERATURE FROM 40*C. TO 80*C. UNTIL THE ETHERIFICATION IS SUBSTANTIALLY COMPLETE, TO PRODUCE A HYDROXYALKYL METHYL CELLULOSE WHICH IS BOTH COLD WATER-SOLUBLE AND THEROMPLASTIC.
References Cited (Backward Citations)
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US2033126A
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US2388764A
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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) | 1961-04-21 | 1961-10-21 | 1962-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-04-21 | 1965-10-21 | 1966-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-04-21 | 1969-10-21 | 1970-04-22 | $7700.00 | Window Closed / Lapsed |