Patent US3077373A successfully refreshed from Google Patents.
US3077373A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sulfation of cellulose
Assignee: Unilever Bestfoods North America
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Filing: 1960-04-12
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Granted: 1963-02-12
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Expires: 1980-04-12
Abstract
No abstract record available.
Inventors
- 👤 Ralph W Kerr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 21:17
CPC Classifications
C; C08; C08B; C08B5/00; C08B5/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
83 words
A PROCESS FOR SULFATING CELLULOSE, CELLULOSE DERIVATIVES CONTAINING AT LEAST ONE FREE HYDROXYL GROUP AND MIXTURES THEREOF WHICH COMPRISES PRE-TREATING SAID CELLULOSIC SUBSTANCE WITH AT LEAST ABOUT 10 PERCENT BY WEIGHT OF SAID CELLULOSIC SUBSTANCE OF AN ALKALINE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF SODIUM HYDROXIDE, POTASSIUM HYDROXIDE AND CALCIUM HYDROXIDE FOR A TIME SUFFICIENT TO OPEN UP THE LATTICES OF MOLECULES OF SAID CELLULOSIC SUBSTANCE AND REACTING SAID PRE-TREATED CELLULOSIC SUBSTANCE WITH A SULFUR TRIOXIDE-TERTIARY AMINE COMPOUNDS IN AN AQUEOUS MEDIUM.
Claim 2
Dependent Claim
83 words
A PROCESS FOR SULFATING CELLULOSE, CELLULOSE DERIVATIVES CONTAINING AT LEAST ONE FREE HYDROXYL GROUP AND MIXTURES THEREOF WHICH COMPRISES PRE-TREATING SAID CELLULOSIC SUBSTANCE WITH AT LEAST ABOUT 10 PERCENT BY WEIGHT OF SAID CELLULOSIC SUBSTANCE OF AN ALKALINE SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF SODIUM HYDROXIDE, POTASSIUM HYDROXIDE AND CALCIUM HYDROXIDE FOR A TIME SUFFICIENT TO OPEN UP THE LATTICES OF MOLECULES OF SAID CELLULOSIC SUBSTANCE AND REACTING SAID PRE-TREATED CELLULOSIC SUBSTANCE WITH A SULFUR TRIOXIDE-TERTIARY AMINE COMPOUNDS IN AN AQUEOUS MEDIUM.
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) | 1966-02-11 | 1966-08-13 | 1967-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-02-11 | 1970-08-13 | 1971-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-02-11 | 1974-08-13 | 1975-02-12 | $7700.00 | Window Closed / Lapsed |