US3351583A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of hydroxypropyl cellulose
Assignee: Hercules LLC
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Filing: 1964-07-06
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Granted: 1967-11-07
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Expires: 1984-07-06
Abstract
No abstract record available.
Inventors
- 👤 Robert G Bishop
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:11
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/02; C08B11/04; C08B11/08
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
65 words
PROCESS OF PREPARING HYDROXYPROPYL CELLULOSE ETHERS HAVING AN M.S. OF A T LEAST 2 WHICH COMPRISES DISPERSING CELLULOSIC MATERIAL IN A LIQUID DISPERSANT SELECTED FROM THE GROUP CONSISTING OF WATER-IMMISCIBLE DISPERSANT AND MIXTURES OF WATER-MISCIBLE AND WATER-IMMISCIBLE DISPERSANT, AGITATING THE RESULTING DISPERSION AT A TEMPERATURE OF ABOUT 55*C.-110*C. IN THE PRESENCE OF ALKALI, WATER, AND PROPYLENE OXIDE, AND EMPLOYING THE FOLLOWING WEIGHT RATIOS TO CELLULOSE:
Claim 2
Dependent Claim
65 words
PROCESS OF PREPARING HYDROXYPROPYL CELLULOSE ETHERS HAVING AN M.S. OF A T LEAST 2 WHICH COMPRISES DISPERSING CELLULOSIC MATERIAL IN A LIQUID DISPERSANT SELECTED FROM THE GROUP CONSISTING OF WATER-IMMISCIBLE DISPERSANT AND MIXTURES OF WATER-MISCIBLE AND WATER-IMMISCIBLE DISPERSANT, AGITATING THE RESULTING DISPERSION AT A TEMPERATURE OF ABOUT 55*C.-110*C. IN THE PRESENCE OF ALKALI, WATER, AND PROPYLENE OXIDE, AND EMPLOYING THE FOLLOWING WEIGHT RATIOS TO CELLULOSE:
References Cited (Backward Citations)
US2572039A
Cited
US2976278A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-11-06 | 1971-05-08 | 1971-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-11-06 | 1975-05-08 | 1975-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-11-06 | 1979-05-08 | 1979-11-07 | $7700.00 | Window Closed / Lapsed |