US2957795A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for making paper pulp
Assignee: John W Bolton and Sons Inc
•
Filing: 1956-06-07
•
Granted: 1960-10-25
•
Expires: 1976-06-07
Abstract
No abstract record available.
Inventors
- 👤 Harold D Stuck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:53
CPC Classifications
D; D21; D21B; D21B1/00; D21B1/04; D21B1/12
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
140 words
IN A PROCESS FOR MAKING PAPER PULP FROM WOOD, THE STEPS OF SUBJECTING PIECES OF WOOD TO THE DIGESTING ACTION OF HOT COOKING LIQUOR AT SUPER ATMOSPHERIC PRESSURE FOR A TIME SUFFICIENT TO SOFTEN THE ENCRUSTANT BOND HOLDING THE CELLULOSE FIBRES TOGETHER AND PRODUCE A PULP OF RELATIVELY HIGH CONSISTENCY, THEN BLOWING A THIN, VALVE CONTROLLED, HIGH CONSISTENCY, STREAM OF SAID COOKED AND COOKING LIQUOR INTO A PRESSURE TIGHT ENVIROMENT IN A CONSTRICTED FLOW, THEN, IN SAID ENVIRONMENT, CENTRIFUGALIZING SAID COOKED WOOD AND COOKING LIQUOR WHILE STILL HOT AND STILL AT SUPER ATMOSPHERIC PRESSURE AT HIGH SPEED WHILE SUBJECTING THE SAME TO DISINTEGRATING IMPACTS ALTERNATELY IN OPPOSITE ANGULAR DIRECTIONS, THEN DILUTING SAID PULP TO A LOWER CONSISTENCY WITH HOT COOKING LIQUOR AT A TEMPERATURE OF ABOUT 170*F. AND THEN RELIEVING THE SUPER ATMOSPHERIC PRESSURE ON SAID WHIRLED AND COOKED PIECES.
Claim 2
Dependent Claim
140 words
IN A PROCESS FOR MAKING PAPER PULP FROM WOOD, THE STEPS OF SUBJECTING PIECES OF WOOD TO THE DIGESTING ACTION OF HOT COOKING LIQUOR AT SUPER ATMOSPHERIC PRESSURE FOR A TIME SUFFICIENT TO SOFTEN THE ENCRUSTANT BOND HOLDING THE CELLULOSE FIBRES TOGETHER AND PRODUCE A PULP OF RELATIVELY HIGH CONSISTENCY, THEN BLOWING A THIN, VALVE CONTROLLED, HIGH CONSISTENCY, STREAM OF SAID COOKED AND COOKING LIQUOR INTO A PRESSURE TIGHT ENVIROMENT IN A CONSTRICTED FLOW, THEN, IN SAID ENVIRONMENT, CENTRIFUGALIZING SAID COOKED WOOD AND COOKING LIQUOR WHILE STILL HOT AND STILL AT SUPER ATMOSPHERIC PRESSURE AT HIGH SPEED WHILE SUBJECTING THE SAME TO DISINTEGRATING IMPACTS ALTERNATELY IN OPPOSITE ANGULAR DIRECTIONS, THEN DILUTING SAID PULP TO A LOWER CONSISTENCY WITH HOT COOKING LIQUOR AT A TEMPERATURE OF ABOUT 170*F. AND THEN RELIEVING THE SUPER ATMOSPHERIC PRESSURE ON SAID WHIRLED AND COOKED PIECES.
References Cited (Backward Citations)
US850384A
Cited
US1827710A
Cited
US1970330A
Cited
US2323194A
Cited
US2591106A
Cited
US2730931A
Cited
US2662821A
Cited
US2616802A
Cited
US2709652A
Cited
US2791503A
Cited
US2718821A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-10-25 | 1964-04-25 | 1964-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-10-25 | 1968-04-25 | 1968-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-10-25 | 1972-04-25 | 1972-10-25 | $7700.00 | Window Closed / Lapsed |