US2934531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Manufacture of lignin derivatives
Assignee: International Paper Canada Inc
•
Filing: 1957-12-02
•
Granted: 1960-04-26
•
Expires: 1977-12-02
Abstract
No abstract record available.
Inventors
- 👤 John L Gardon
- 👤 Leopold Bengt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 05:16
CPC Classifications
D; D21; D21H; D21H17/00; D21H17/20; D21H17/21; D21H17/23
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
47 words
IN A PROCESS OF OBTAINING HIGHLY REACTIVE LIGNIN PRODUCTS OF HIGH CARBONYL AND PHENOLIC HYDROXYL CONTENT, THE STEP OF HEATING A REACTION MIXTURE CONSISTING OF A LIGNIN SULPHONATE SALT AND A SOLID ALKALINE REAGENT IN THE DRY STATE AT A TEMPERATURE BETWEEN 220* C. AND 350* C.
Claim 2
Dependent Claim
47 words
IN A PROCESS OF OBTAINING HIGHLY REACTIVE LIGNIN PRODUCTS OF HIGH CARBONYL AND PHENOLIC HYDROXYL CONTENT, THE STEP OF HEATING A REACTION MIXTURE CONSISTING OF A LIGNIN SULPHONATE SALT AND A SOLID ALKALINE REAGENT IN THE DRY STATE AT A TEMPERATURE BETWEEN 220* C. AND 350* C.
References Cited (Backward Citations)
US1298477A
Cited
US2683706A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-04-26 | 1963-10-26 | 1964-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-04-26 | 1967-10-26 | 1968-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-04-26 | 1971-10-26 | 1972-04-26 | $7700.00 | Window Closed / Lapsed |