Patent US2553725A successfully refreshed from Google Patents.
US2553725A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of preparing cellulose derivatives
Assignee: Buckeye Cotton Oil Co
•
Filing: 1948-09-10
•
Granted: 1951-05-22
•
Expires: 1968-09-10
Abstract
No abstract record available.
Inventors
- 👤 Linwood N Rogers
- 👤 William A Mueller
- 👤 Ernest E Hembree
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 03:45
CPC Classifications
C; C08; C08B; C08B11/00; C08B11/02; C08B11/04; C08B11/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
135 words
IN THE PROCESS OF PREPARING SALTS OF ACIDIC ETHER DERIVATIVES OF CELLULOSE FROM CELLULOSE PULP, THE STEPS WHICH COMPRISE (1) CONTACTING THE PULP IN THE FORM OF A CONTINUOUS SHEET, WHILE FEEDING THE SHEET, THROUGH A HYDROLYZING ZONE, WITH A MINERAL ACID AT ELEVATED TEMPERATURE FOR A PERIOD OF TIME SUFFICIENT TO EFFECT SUBSTANTIAL DEPOLYMERIZATION OF THE PULP, (2) WASHING AND DRYING THE SHEET WHILE FEEDING THE SHEET THROUGH AN ACID REMOVAL ZONE, AND (3) IMPREGNATING THE SHEET, ZONE, WITH AN AQUEOUS SOLUTION OF A HALOGENATED WHILE FEEDING THE SHEET THROUGH AN ETHERIFYING ACID OF THE GROUP CONSISTING OF HALOGENATED ALIPHATIC CARBOXYLIC AND HALOGENATED ALKYL SULFONIC ACIDS HAVING NOT MORE THAN 4 CARBON ATOMS IN THE MOLECULE AND AN ALKALINE AGENT IN TOTAL AMOUNT NOT GREATER THAN THAT WHICH THE SHEET IS CAPABLE OF ABSORBING.
Claim 2
Dependent Claim
135 words
IN THE PROCESS OF PREPARING SALTS OF ACIDIC ETHER DERIVATIVES OF CELLULOSE FROM CELLULOSE PULP, THE STEPS WHICH COMPRISE (1) CONTACTING THE PULP IN THE FORM OF A CONTINUOUS SHEET, WHILE FEEDING THE SHEET, THROUGH A HYDROLYZING ZONE, WITH A MINERAL ACID AT ELEVATED TEMPERATURE FOR A PERIOD OF TIME SUFFICIENT TO EFFECT SUBSTANTIAL DEPOLYMERIZATION OF THE PULP, (2) WASHING AND DRYING THE SHEET WHILE FEEDING THE SHEET THROUGH AN ACID REMOVAL ZONE, AND (3) IMPREGNATING THE SHEET, ZONE, WITH AN AQUEOUS SOLUTION OF A HALOGENATED WHILE FEEDING THE SHEET THROUGH AN ETHERIFYING ACID OF THE GROUP CONSISTING OF HALOGENATED ALIPHATIC CARBOXYLIC AND HALOGENATED ALKYL SULFONIC ACIDS HAVING NOT MORE THAN 4 CARBON ATOMS IN THE MOLECULE AND AN ALKALINE AGENT IN TOTAL AMOUNT NOT GREATER THAN THAT WHICH THE SHEET IS CAPABLE OF ABSORBING.
References Cited (Backward Citations)
US1503604A
Cited
US1864554A
Cited
US2060056A
Cited
US2101263A
Cited
US2159375A
Cited
US2278612A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-05-21 | 1954-11-20 | 1955-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-05-21 | 1958-11-20 | 1959-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-05-21 | 1962-11-20 | 1963-05-22 | $7700.00 | Window Closed / Lapsed |