Patent US4271079A successfully refreshed from Google Patents.
US4271079A
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5-(2,5-Dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride
Assignee: DIC Corp
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Filing: 1979-09-05
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Granted: 1981-06-02
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Expires: 1999-09-05
Abstract
Abstract A novel compound, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, of the following formula is provided. <IMAGE> This novel tetracarboxylic acid dianhydride is useful as a curing agent for epoxy resins.
Inventors
- 👤 Hiroshi Maeda
- 👤 Nagao Ariga
- 👤 Hiroshi Oikawa
- 👤 Hidemitsu Tominaga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:21
CPC Classifications
C; C08; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/42; C08G59/4215; C07; C07C; C07C61/00; C07C61/16; C07C61/22
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
7 words
Tetracarboxylic acid dianhydride of the formula: ##STR7##
Claim 2
Dependent Claim
7 words
Tetracarboxylic acid dianhydride of the formula: ##STR7##
References Cited (Backward Citations)
US3264261A
Cited
US3391223A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-06-01 | 1984-12-01 | 1985-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-01 | 1988-12-01 | 1989-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-01 | 1992-12-01 | 1993-06-02 | $7700.00 | Window Closed / Lapsed |