Patent US2749240A successfully refreshed from Google Patents.
US2749240A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of cellulose pulp
Assignee: FPInnovations
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Filing: 1953-01-19
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Granted: 1956-06-05
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Expires: 1973-01-19
Abstract
No abstract record available.
Inventors
- 👤 Ross James Hamilton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 10:26
CPC Classifications
D; D21; D21C; D21C3/00; D21C3/22; D21C1/00; D21C1/10
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
111 words
IN THE PRODUCTION OF CELLULOSIC PULP THE PROCESS OF IMPREGNATING A FINELY DIVIDED CELLULOSIC MATERIAL WITH AN AQUEOUS COOKING LIQUOR COMPRISING PLACING SAID CELLULOSIC MATERIAL IN A PRESSURE VESSEL, INTRODUCING STEAM TO SAID PRESSURE VESSEL TO ESTABLISH AN ATMOSPHERE OF STEAM AND AIR IN DIRECT CONTACT WITH SAID CELLULOSIC MATERIAL AT A SUPER-ATMOSPHERIC PRESSURE OF AT LEAST ABOUT TWO ATMOSPHERES BEFORE THE INTRODUCTION OF COOKING LIQUOR TO SAID CELLULOSIC MATERIAL, AND THEREAFTER FORCING AN AQUEOUS COOKING LIQUOR INTO SAID PRESSURE VESSEL TO SUBMERGE SAID CELLULOSIC MATERIAL WHILE MAINTAINING SAID CELLULOSIC MATERIAL AND THE LIQUOR IN WHICH IT IS BEING SUBMERGED UNDER A PRESSURE AT LEAST AS GREAT AS SAID SUPER-ATMOSPHERIC PRESSURE.
Claim 2
Dependent Claim
111 words
IN THE PRODUCTION OF CELLULOSIC PULP THE PROCESS OF IMPREGNATING A FINELY DIVIDED CELLULOSIC MATERIAL WITH AN AQUEOUS COOKING LIQUOR COMPRISING PLACING SAID CELLULOSIC MATERIAL IN A PRESSURE VESSEL, INTRODUCING STEAM TO SAID PRESSURE VESSEL TO ESTABLISH AN ATMOSPHERE OF STEAM AND AIR IN DIRECT CONTACT WITH SAID CELLULOSIC MATERIAL AT A SUPER-ATMOSPHERIC PRESSURE OF AT LEAST ABOUT TWO ATMOSPHERES BEFORE THE INTRODUCTION OF COOKING LIQUOR TO SAID CELLULOSIC MATERIAL, AND THEREAFTER FORCING AN AQUEOUS COOKING LIQUOR INTO SAID PRESSURE VESSEL TO SUBMERGE SAID CELLULOSIC MATERIAL WHILE MAINTAINING SAID CELLULOSIC MATERIAL AND THE LIQUOR IN WHICH IT IS BEING SUBMERGED UNDER A PRESSURE AT LEAST AS GREAT AS SAID SUPER-ATMOSPHERIC PRESSURE.
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) | 1959-06-05 | 1959-12-05 | 1960-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-06-05 | 1963-12-05 | 1964-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-06-05 | 1967-12-05 | 1968-06-05 | $7700.00 | Window Closed / Lapsed |