US3779994A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for preparing polyurethane from polyisocyanate and polyalkanolamine using a blocking acid salt
Assignee: WR Grace and Co
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Filing: 1972-10-26
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Granted: 1973-12-18
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Expires: 1992-10-26
Abstract
Abstract THE INVENTION DISCLOSED IS A METHOD FOR PREPARING NEW CURABLE WATER SOLUBLE POLYMERS. THE PRODUCT POLYMERS UPON BEING CURED ARE CHARACTERISTICALLY WATER INSOLUBLE AND WHEN APPLIED TO FIBERS PROVIDE USEFUL WET STRENGTH ADDITIVES.
Inventors
- 👤 L Wood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 10:23
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/30; C08G18/32; C08G18/3271; C08G18/3296; C08G18/08; C08G18/0804; C08G18/0809; C08G18/0814
Claims Analysis
Total Claims: 0
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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) | 1976-12-17 | 1977-06-18 | 1977-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-17 | 1981-06-18 | 1981-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-17 | 1985-06-18 | 1985-12-18 | $7700.00 | Window Closed / Lapsed |