Patent US3607814A successfully refreshed from Google Patents.
US3607814A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composition of matter comprising a solution of a polyimide in a mixture of solvents
Assignee: Wyeth Holdings LLC
•
Filing: 1969-02-17
•
Granted: 1971-09-21
•
Expires: 1989-02-17
Abstract
Abstract A composition of matter comprising a solution of a polyimide of a 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene succinic dianhydride and a diprimary diamine in the presence of a mixture of solvents comprising butyrolactone and a ketone selected from the group consisting of acetophenone, isopharone, benzophenone propiophenone and cyclohexanone in certain proportions and solids.
Inventors
- 👤 Roland Ralph Dileone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:59
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1003; C08G73/1007; C08G73/1028; C08G73/1032
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
33 words
The composition according to claim 1 in which the solids content of the polyimide in solution is between about 15 percent and 20 percent by weight based on the total weight of solution.
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) | 1974-09-20 | 1975-03-22 | 1975-09-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-20 | 1979-03-22 | 1979-09-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-20 | 1983-03-22 | 1983-09-21 | $7700.00 | Window Closed / Lapsed |