US2676170A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water-soluble derivatives of unsulfonated lignin
Assignee: EIDP Inc
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Filing: 1950-07-15
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Granted: 1954-04-20
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Expires: 1970-07-15
Abstract
No abstract record available.
Inventors
- 👤 Patterson George Harold
- 👤 Balon Walter Jean
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 16:36
CPC Classifications
C; C14; C14C; C14C3/00; C14C3/02; C14C3/08; C14C3/24
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
46 words
THE PROCESS OF PRODUCING A WATER-SOLUBLE DERIVATIVE OF LIGNIN, HAVING TANNING POWERS, WHICH COMPRISES REACTING LIGNIN, IN ALKALINE SOLUTION AND AT A TEMPERATURE BETWEEN ROOM TEMPERATURE AND 105* C., WITH FORMALDEHYDE AND A HALOGENOALIPHATIC CARBOXYLIC ACID, AND ACIDIFYING THE REACTION MASS TO PRECIPITATE THE REACTION PRODUCT.
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) | 1957-04-19 | 1957-10-19 | 1958-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-04-19 | 1961-10-19 | 1962-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-04-19 | 1965-10-19 | 1966-04-20 | $7700.00 | Window Closed / Lapsed |