US3577388A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fiber prepared from polyester based polyurethane prepolymer
Assignee: Wyeth Holdings LLC
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Filing: 1969-05-14
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Granted: 1971-05-04
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Expires: 1989-05-14
Abstract
Abstract POLYURETHANE SPINNING SOLUTIONS WHICH YIELD SPANDEX FIBERS OF IMPROVED ELASTICITY ARE PREPARED BY REACTING AN EXCESS OF AN ORGANIC DIISOCYANATE WITH A HYDROXYL TERMINATED POLYESTER PREPARED BY REACTING ADIPIC ACID WITH AN EXCESS OF A MIXTURE OF 1,4-BUTYLENE GLYCOL AND1,2-PROPYLENE GLYCOL WHEREIN THE GLYCOLS ARE PRESENT IN A MOLE RATIO OF BETWEEN 80:20 AND 95:5, AND THEN CHAIN EXTENDING THE RESULTING PREPOLYMER WITH A DIAMINE.
Inventors
- 👤 Ignazio Salvatore Megna
- 👤 Anthony Koroscil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:25
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/42; C08G18/4236; C08G18/4238; C08G18/08; C08G18/0838; C08G18/0842; C08G18/0847; C08G18/0852; C08G18/10; Y; Y10; Y10S; Y10S528/00; Y10S528/906
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) | 1974-05-03 | 1974-11-02 | 1975-05-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-03 | 1978-11-02 | 1979-05-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-03 | 1982-11-02 | 1983-05-04 | $7700.00 | Window Closed / Lapsed |