Patent US3956320A successfully refreshed from Google Patents.
US3956320A
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Aromatic bis(ether phthalis anhydride) compounds
Assignee: General Electric Co
•
Filing: 1974-08-02
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Granted: 1976-05-11
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Expires: 1994-08-02
Abstract
Abstract Aromatic bis(ether anhydride)s are prepared from the hydrolysis of the reaction product of a nitro-substituted phenyl dinitrile with a metal salt of a dihydroxy aryl compound in the presence of a dipolar aprotic solvent.
Inventors
- 👤 Darrell R. Heath
- 👤 Joseph G. Wirth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:29
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1057; C08G73/1064; C07; C07C; C07C65/00; C07C65/21; C07C65/24; C07D; C07D307/00; C07D307/77; C07D307/87; C07D307/89; C08G59/00; C08G59/18; C08G59/40; C08G59/42; C08G59/4223; C08G59/423; C08G73/1046; C08G73/1053; C08G73/1067; C08G73/1071
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
3 words
The compound ##SPC31##
Claim 2
Dependent Claim
3 words
The compound ##SPC31##
Claim 3
Dependent Claim
3 words
The compound ##SPC32##
Claim 4
Dependent Claim
3 words
The compound ##SPC32##
Claim 5
Dependent Claim
3 words
The compound ##SPC33##
Claim 6
Dependent Claim
3 words
The compound ##SPC33##
Claim 7
Dependent Claim
3 words
The compound ##SPC34##
Claim 8
Dependent Claim
3 words
The compound ##SPC34##
Claim 9
Dependent Claim
3 words
The compound ##SPC35##
Claim 10
Dependent Claim
3 words
The compound ##SPC35##
Claim 11
Dependent Claim
3 words
The compound ##SPC36##
Claim 12
Dependent Claim
3 words
The compound ##SPC36##
Claim 13
Dependent Claim
23 words
An aromatic bis(ether anhydride) of the formula ##SPC37## where R 1 is a member selected from the class consisting of 4,4'-diphenyl and 4,4'-diphenylsulfide.
Claim 14
Dependent Claim
23 words
An aromatic bis(ether anhydride) of the formula ##SPC37## where R 1 is a member selected from the class consisting of 4,4'-diphenyl and 4,4'-diphenylsulfide.
Claim 15
Dependent Claim
12 words
A compound in accordance with claim 7, where R 1 is 4,4'-biphenyl.
Claim 16
Dependent Claim
12 words
A compound in accordance with claim 7, where R 1 is 4,4'-diphenylsulfide.
References Cited (Backward Citations)
US3787475A
Cited
US3850964A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-05-11 | 1979-11-10 | 1980-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-11 | 1983-11-10 | 1984-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-11 | 1987-11-10 | 1988-05-11 | $7700.00 | Window Closed / Lapsed |