US2969356A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of sulfuric acid esters of cellulose
Assignee: Eastman Kodak Co
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Filing: 1958-05-15
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Granted: 1961-01-24
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Expires: 1978-05-15
Abstract
No abstract record available.
Inventors
- 👤 George P Touey
- 👤 John E Kiefer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 04:39
CPC Classifications
C; C08; C08B; C08B5/00; C08B5/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
89 words
A METHOD OF PREPARING SULFURIC ACID ESTERS OF CELLULOSE WHICH COMPRISES REACTING UNDER ANHYDROUS CONDITIONS UPON 1 PART SOLID WIEHGT OF AN ACTIVATED CELLULOSE AT 0-15*C. WITH 0.2-1.0 PART OF A SULFATING AGENT SELECTED FROM THE GROUP CONSISTING OF SULFURIC ACID AND FUMING SULFURIC ACID, FATTY ACID OF 3-4 CARBON ATOMS AS THE SOLVENT THEREIN AND LOWER FATTY ACID ANHYDRIDE WITHIN THE RANE OF 0.3-2 PARTS, IN SLIGHT EXCESS OF THAT SUFFICIENT TO DESTROY ALL THE WATER PRESENT IN THE SYSTEM AND FORMED DURING THE COURSE OF THE ESTERIFICATION.
Claim 2
Independent Claim
89 words
A METHOD OF PREPARING SULFURIC ACID ESTERS OF CELLULOSE WHICH COMPRISES REACTING UNDER ANHYDROUS CONDITIONS UPON 1 PART SOLID WIEHGT OF AN ACTIVATED CELLULOSE AT 0-15*C. WITH 0.2-1.0 PART OF A SULFATING AGENT SELECTED FROM THE GROUP CONSISTING OF SULFURIC ACID AND FUMING SULFURIC ACID, FATTY ACID OF 3-4 CARBON ATOMS AS THE SOLVENT THEREIN AND LOWER FATTY ACID ANHYDRIDE WITHIN THE RANE OF 0.3-2 PARTS, IN SLIGHT EXCESS OF THAT SUFFICIENT TO DESTROY ALL THE WATER PRESENT IN THE SYSTEM AND FORMED DURING THE COURSE OF THE ESTERIFICATION.
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) | 1964-01-24 | 1964-07-25 | 1965-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-01-24 | 1968-07-25 | 1969-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-01-24 | 1972-07-25 | 1973-01-24 | $7700.00 | Window Closed / Lapsed |