Patent US3173908A successfully refreshed from Google Patents.
US3173908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of fractionating polysaccharide mixtures
Assignee: Dart Industries Inc
•
Filing: 1962-12-17
•
Granted: 1965-03-16
•
Expires: 1982-12-17
Abstract
No abstract record available.
Inventors
- 👤 Seymour H Mann
- 👤 Michael R Rusch
- 👤 Robert E Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:29
CPC Classifications
C; C13; C13K; C13K13/00; C13K13/007; A; A23; A23L; A23L27/00; A23L27/30; A23L27/33; C08; C08B; C08B30/00; C08B30/20; C08B37/00; C08B37/0003
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
160 words
A METHOD OF SEPARATING A HETEROGENEOUS MIXTURE OF POLYSACCHARIDES INTO FRACTIONS HAVING LOWER AND HIGHER AVERAGE DEGREES OF POLYMERIZATION WHICH COMPRISES INTRODUCING INTO THE UPPER PORTION OF A LIQUID-LIQUID CONTACTING ZONE AN AQUEOUS SOLUTION CONTAINING NOT MORE THAN 30% BY WEIGHT OF SAID HETEROGENEOUS MIXTURE, INTRODUCING INTO A LOWER PORTION OF SAID ZONE A WATER-MISCIBLE ORGANIC SOLVENT, THE RATIO BY WEIGHT OF SAID ORGANIC SOLVENT TO WATER IN SAID ZONE BEING BETWEEN ABOUT 1 TO 1 AND ABOUT 6 TO 1, WITHDRAWING FROM THE UPPER PORTION OF SAID ZONE AT A LOCATION ABOVE THE POINT OF INTRODUCTION OF THE AQUEOUS SOLUTION OF SAID HETEROGENEOUS MIXTURE A SOLUTION OF POLYSACCHARIDES HAVING A LOWER AVERAGE DEGREE OF POLYMERIZATION, AND WITHDRAWING FROM A LOCATION BELOW THE POINT OF INTRODUCTION OF SAID ORGANIC SOLVENT A SOLUTION OF POLYSACCHARIDES HAVING A HIGHER AVERAGE DEGREE OF POLYMERIZATION, THE TEMPERATURE WITHIN SAID ZONE BEING MAINTAINED AT A SUBSTANTIALLY CONSTANT VALUE WITHIN THE RANGE OF 0*C. TO 75*C.
Claim 2
Independent Claim
160 words
A METHOD OF SEPARATING A HETEROGENEOUS MIXTURE OF POLYSACCHARIDES INTO FRACTIONS HAVING LOWER AND HIGHER AVERAGE DEGREES OF POLYMERIZATION WHICH COMPRISES INTRODUCING INTO THE UPPER PORTION OF A LIQUID-LIQUID CONTACTING ZONE AN AQUEOUS SOLUTION CONTAINING NOT MORE THAN 30% BY WEIGHT OF SAID HETEROGENEOUS MIXTURE, INTRODUCING INTO A LOWER PORTION OF SAID ZONE A WATER-MISCIBLE ORGANIC SOLVENT, THE RATIO BY WEIGHT OF SAID ORGANIC SOLVENT TO WATER IN SAID ZONE BEING BETWEEN ABOUT 1 TO 1 AND ABOUT 6 TO 1, WITHDRAWING FROM THE UPPER PORTION OF SAID ZONE AT A LOCATION ABOVE THE POINT OF INTRODUCTION OF THE AQUEOUS SOLUTION OF SAID HETEROGENEOUS MIXTURE A SOLUTION OF POLYSACCHARIDES HAVING A LOWER AVERAGE DEGREE OF POLYMERIZATION, AND WITHDRAWING FROM A LOCATION BELOW THE POINT OF INTRODUCTION OF SAID ORGANIC SOLVENT A SOLUTION OF POLYSACCHARIDES HAVING A HIGHER AVERAGE DEGREE OF POLYMERIZATION, THE TEMPERATURE WITHIN SAID ZONE BEING MAINTAINED AT A SUBSTANTIALLY CONSTANT VALUE WITHIN THE RANGE OF 0*C. TO 75*C.
References Cited (Backward Citations)
US1297171A
Cited
US2214206A
Cited
US2400962A
Cited
GB827494A
Cited
US2976274A
Cited
US3094517A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-03-15 | 1968-09-14 | 1969-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-03-15 | 1972-09-14 | 1973-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-03-15 | 1976-09-14 | 1977-03-16 | $7700.00 | Window Closed / Lapsed |