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US4303531B1
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US4303531B1 - - Google Patents
Assignee: Koei Chemical Co Ltd
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Filing: 1979-11-27
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Granted: 1988-08-23
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Expires: 1999-11-27
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:45
CPC Classifications
C; C02; C02F; C02F1/00; C02F1/28; C02F1/285; Y; Y10; Y10S; Y10S210/00; Y10S210/902; Y10S210/908; Y10S210/909
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) | 1991-08-23 | 1992-02-22 | 1992-08-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-08-23 | 1996-02-22 | 1996-08-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-08-23 | 2000-02-22 | 2000-08-23 | $7700.00 | Window Closed / Lapsed |