US2714591A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cellulose sulfate preparation
Assignee: Hercules Powder Co
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Filing: 1951-09-08
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Granted: 1955-08-02
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Expires: 1971-09-08
Abstract
No abstract record available.
Inventors
- 👤 Eugene D Klug
- 👤 Harold M Spurlin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:04
CPC Classifications
C; C08; C08B; C08B5/00; C08B5/14
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
126 words
A PROCESS FOR PREPARING CELLULOSE SULFATE WHICH COMPRISES STEEPING CELLULOSE IN A BATH OF STEEPING LIQUOR COMPRISING ESSENTIALLY BETWEEN ABOUT 20% AND 70% BY WEIGHT OF SULFURIC ACID OF AT LEAST ABOUT 90% AND NOT MORE THAN 100% STRENGTH DISSOLVED IN LOWER FATTY ACID UNTIL SAID CELLUILOSE IS UNIFORMLY IMPREGNATED WITH SAID STEEPING LIQUOR, REMOVING EXCESS STEEPING LIQUOR TO ADJUST THE AMOUNT OF SULFURIC ACID DISTRIBUTED ON THE CELLULOSE TO NOT MORE THAN ABOUT 10 MOLES PER ANHYDROGLUCOSE UNIT, SUSPENDING THE STEEPED CELLULOSE, FOLLOWING REMOVALAL OF EXCESS STEEPING LIQUOR, IN AN INERT ORGANIC LIQUID SELECTED FROM THE GROUP CONSISTING OF LIQUID HYDROCARBONS AND LIQUID CHLORINATED HYDROCARBONS TO FORM A SLURRY, AND SULFATING THE CELLULOSE, THE ENTIRE PROCESS BEING CONDUCTED AT A TEMPERATURE BELOW ABOUT 20* C.
Claim 2
Dependent Claim
126 words
A PROCESS FOR PREPARING CELLULOSE SULFATE WHICH COMPRISES STEEPING CELLULOSE IN A BATH OF STEEPING LIQUOR COMPRISING ESSENTIALLY BETWEEN ABOUT 20% AND 70% BY WEIGHT OF SULFURIC ACID OF AT LEAST ABOUT 90% AND NOT MORE THAN 100% STRENGTH DISSOLVED IN LOWER FATTY ACID UNTIL SAID CELLUILOSE IS UNIFORMLY IMPREGNATED WITH SAID STEEPING LIQUOR, REMOVING EXCESS STEEPING LIQUOR TO ADJUST THE AMOUNT OF SULFURIC ACID DISTRIBUTED ON THE CELLULOSE TO NOT MORE THAN ABOUT 10 MOLES PER ANHYDROGLUCOSE UNIT, SUSPENDING THE STEEPED CELLULOSE, FOLLOWING REMOVALAL OF EXCESS STEEPING LIQUOR, IN AN INERT ORGANIC LIQUID SELECTED FROM THE GROUP CONSISTING OF LIQUID HYDROCARBONS AND LIQUID CHLORINATED HYDROCARBONS TO FORM A SLURRY, AND SULFATING THE CELLULOSE, THE ENTIRE PROCESS BEING CONDUCTED AT A TEMPERATURE BELOW ABOUT 20* C.
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) | 1958-08-01 | 1959-01-31 | 1959-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-08-01 | 1963-01-31 | 1963-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-08-01 | 1967-01-31 | 1967-08-02 | $7700.00 | Window Closed / Lapsed |