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US3671524A
Expired / Lapsed
US
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Triazinyl-coumarins
Assignee: Showa Kagaku Kogyo Co Ltd
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Filing: 1968-09-18
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Granted: 1972-06-20
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Expires: 1988-09-18
Abstract
Abstract WHEREIN R represents an alkyl group having one to four carbon atoms, each of R1, R2 and R3 represents a hydrogen atom, or a lower alkyl group, and X represents a divalent organic residue such as lower alkylene group, hydroxy(lower)alkylene group or phenylene group, characterized by treating cyanuric chloride with an alcohol represented by the formula A process for preparing a fluorescent whitening agent of the formula
Inventors
- 👤 Kazuaki Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 22:32
CPC Classifications
D; D06; D06L; D06L4/00; D06L4/60
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US3184459A
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US2945033A
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US3242177A
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US3250772A
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US3518266A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |