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US3519581A
Expired / Lapsed
US
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Method of producing synthetic lignin-polyisocyanate resin
Assignee: Westvaco Corp
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Filing: 1967-01-13
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Granted: 1970-07-07
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Expires: 1987-01-13
Abstract
No abstract record available.
Inventors
- 👤 Howard H Moorer
- 👤 Walter K Dougherty
- 👤 Frank J Ball
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:18
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/64; C08G18/6492
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2854422A
Cited
US2906718A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-07-06 | 1974-01-05 | 1974-07-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-07-06 | 1978-01-05 | 1978-07-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-07-06 | 1982-01-05 | 1982-07-07 | $7700.00 | Window Closed / Lapsed |