US3453292A
Expired / Lapsed
US
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Method of manufacturing tetracarboxylic acid dianhydride
Assignee: Sumitomo Electric Industries Ltd
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Filing: 1965-06-29
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Granted: 1969-07-01
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Expires: 1985-06-29
Abstract
No abstract record available.
Inventors
- 👤 Masahiro Izumi
- 👤 Hiroshi Shima
- 👤 Shigeru Matsumura
- 👤 Asano Nobuyuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:05
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/28; C08G18/40; C08G18/64; C08G18/6415; C08G18/6438; C08G73/00; C08G73/06; C08G73/10; C08G73/14; H; H01; H01B; H01B3/00; H01B3/18; H01B3/30; H01B3/303; H01B3/306; H01B3/307; Y; Y10; Y10S; Y10S525/00; Y10S525/928
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-06-30 | 1972-12-30 | 1973-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-06-30 | 1976-12-30 | 1977-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-06-30 | 1980-12-30 | 1981-07-01 | $7700.00 | Window Closed / Lapsed |