US2901389A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulping process
Assignee: Abitibi Power and Paper Co Ltd
•
Filing: 1957-06-10
•
Granted: 1959-08-25
•
Expires: 1977-06-10
Abstract
No abstract record available.
Inventors
- 👤 Hossain Shafi Ul
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 23:46
CPC Classifications
D; D21; D21C; D21C3/00; D21C3/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
47 words
A PROCESS FOR PULPING LIGNOCELLULOSIC MATERIAL COMPRISING THE STEP OF TREATING SAID LIGNOCELLULOSIC MATERIAL AT AN ELEVATED TEMPERATURE WITH AN AQUEOUS SOLUTION COMPRISING DIMETHYL SULPHOXIDE IN A CONCENTRATION OF AT LEAST 75% BY WEIGHT IN THE PRESENCE OF AN ACID CATALYST SUBSTANTIALLY TO DELIGNIFY SAID LIGNOCELLULOSIC MATERIAL
Claim 2
Dependent Claim
47 words
A PROCESS FOR PULPING LIGNOCELLULOSIC MATERIAL COMPRISING THE STEP OF TREATING SAID LIGNOCELLULOSIC MATERIAL AT AN ELEVATED TEMPERATURE WITH AN AQUEOUS SOLUTION COMPRISING DIMETHYL SULPHOXIDE IN A CONCENTRATION OF AT LEAST 75% BY WEIGHT IN THE PRESENCE OF AN ACID CATALYST SUBSTANTIALLY TO DELIGNIFY SAID LIGNOCELLULOSIC MATERIAL
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-08-24 | 1963-02-23 | 1963-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-08-24 | 1967-02-23 | 1967-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-08-24 | 1971-02-23 | 1971-08-25 | $7700.00 | Window Closed / Lapsed |