US2906659A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High yields bisulphite pulping process
Assignee: Abitibi Power and Paper Co Ltd
•
Filing: 1953-10-19
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Granted: 1959-09-29
•
Expires: 1973-10-19
Abstract
No abstract record available.
Inventors
- 👤 Rodger M Dorland
- 👤 James W Mckinney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 06:27
CPC Classifications
D; D21; D21C; D21C3/00; D21C3/04; D21C3/06
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
83 words
A SEMI-CHEMICAL PROCESS FOR FORMING PULP CONSISTING ESSENTIALLY OF THE STEPS OF COOKING SUBMERGED WOOD CHIPS FOR ABOUT 21/2 TO 7 HOURS TO WEAKEN THE INTER-FIBER BONDING WITH A SOLUTION OF A BISULPHITE OF A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF SODIUM, POTASSIUM AND AMMONIUM AND HAVING AN INITIAL PH OF NOT LESS THAN 5, THE PH BEING NOT LESS THAN 3 DURING SAID COOKING, SAID SOLUTION HAVING SUBSTANTIALLY NO SULPHUR DIOXIDE IN EXCESS OF THE STOICHIOMETRIC AMOUNT NECESSARY TO FORM SAID
Claim 2
Dependent Claim
83 words
A SEMI-CHEMICAL PROCESS FOR FORMING PULP CONSISTING ESSENTIALLY OF THE STEPS OF COOKING SUBMERGED WOOD CHIPS FOR ABOUT 21/2 TO 7 HOURS TO WEAKEN THE INTER-FIBER BONDING WITH A SOLUTION OF A BISULPHITE OF A SUBSTANCE SELECTED FROM THE GROUP CONSISTING OF SODIUM, POTASSIUM AND AMMONIUM AND HAVING AN INITIAL PH OF NOT LESS THAN 5, THE PH BEING NOT LESS THAN 3 DURING SAID COOKING, SAID SOLUTION HAVING SUBSTANTIALLY NO SULPHUR DIOXIDE IN EXCESS OF THE STOICHIOMETRIC AMOUNT NECESSARY TO FORM SAID
References Cited (Backward Citations)
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Cited
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Cited
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Cited
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Cited
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Cited
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Cited
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-09-28 | 1963-03-30 | 1963-09-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-09-28 | 1967-03-30 | 1967-09-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-09-28 | 1971-03-30 | 1971-09-29 | $7700.00 | Window Closed / Lapsed |