Patent JPS64868A successfully refreshed from Google Patents.
Patent US3556920A successfully refreshed from Google Patents.
US3556920A
Expired / Lapsed
US
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Shaped fibrous laminates impregnated with dianhydride cross-linked epoxy resins
Assignee: Rhone Poulenc SA
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Filing: 1968-02-12
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Granted: 1971-01-19
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Expires: 1988-02-12
Abstract
Abstract DIANHYDRIDES OF FORMULA: BIS(1,3-DI(O=)PHTHALAN-5-YL)-A IN WHICH A IS AN AZO OR AZOXY GROUP, ARE USED AS HARDERNERS FOR EPOXY RES INS WHICH, WHILE EFFECTIVE, DO NOT DEQUIRE THE USE OF A MODERATING AGENT. THEY ARE USEFUL FOR EXAMPLE IN THE PRODUCTION OF LAMINATES AND MOULDED ARTICLES.
Inventors
- 👤 Maurice Balme
- 👤 Max Gruffaz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 17:50
CPC Classifications
C; C07; C07D; C07D303/00; C07D303/02; C07D303/12; C07D303/18; C07D303/20; C07D303/24; C08; C08G; C08G59/00; C08G59/18; C08G59/40; C08G59/42; C08G59/423; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31511; Y10T428/31525; Y10T442/00; Y10T442/30; Y10T442/3472; Y10T442/3528; Y10T442/3569; Y10T442/3585
Claims Analysis
Total Claims: 0
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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) | 1974-01-18 | 1974-07-20 | 1975-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-01-18 | 1978-07-20 | 1979-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-01-18 | 1982-07-20 | 1983-01-19 | $7700.00 | Window Closed / Lapsed |