Patent US3981901A successfully refreshed from Google Patents.
US3981901A
Expired / Lapsed
US
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Novel urethane polythiols
Assignee: WR Grace and Co
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Filing: 1975-07-24
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Granted: 1976-09-21
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Expires: 1995-07-24
Abstract
Abstract A urethane polythiol, which can be a dithiol, is prepared by reacting a hydroxypolythiol, which can be a dithiol, with an isocyanate such as phenyl isocyanate, toluene diisocyanate, and the like.
Inventors
- 👤 James Leverette Guthrie
- 👤 Clifton Leroy Kehr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 14:41
CPC Classifications
C; C08; C08G; C08G75/00; C08G75/12; C08G18/00; C08G18/06; C08G18/28; C08G18/30; C08G18/38; C08G18/3855; C08G18/3876; C08G75/02; C08G75/04; C08G75/045
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
12 words
A polythiol having the formula ##EQU27## in which R 2 is ##SPC5##
Claim 2
Dependent Claim
12 words
A polythiol having the formula ##EQU27## in which R 2 is ##SPC5##
References Cited (Backward Citations)
DE2063948A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-09-21 | 1980-03-22 | 1980-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-09-21 | 1984-03-22 | 1984-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-09-21 | 1988-03-22 | 1988-09-21 | $7700.00 | Window Closed / Lapsed |