Patent US2971139A successfully refreshed from Google Patents.
Patent US3639354A successfully refreshed from Google Patents.
US3639354A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Elastomeric polyurethanes from polycarbonates
Assignee: Bayer AG
•
Filing: 1968-02-23
•
Granted: 1972-02-01
•
Expires: 1988-02-23
Abstract
Abstract POLYURETHANES PREPARED BY REACTING DIISOCYANATES, LOW MOLECULAR WEIGHT COMPOUNDS CONTAINING AT LEAST TWO HYDROGEN ATOMS WHICH ARE REACTIVE WITH ISOCYANATES AND HIGHER MOLECULAR WEIGHT, LINEAR HYDROXYL-CONTAINING POLYCARBONATES BASED ON 1,6-HEXANEDIOL AND AN ALKOXYLATED 1,6-HEXANEDIOL OF THE FORMULA HO-(CH2)6-O-CH(-R)-CH2-OH WHEREIN R IS HYDROGEN OR CH3.
Inventors
- 👤 Erwin Muller
- 👤 Wilhelm Thoma
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:29
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/42; C08G18/44
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1975-01-31 | 1975-08-02 | 1976-02-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-31 | 1979-08-02 | 1980-02-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-31 | 1983-08-02 | 1984-02-01 | $7700.00 | Window Closed / Lapsed |