Patent US3704302A successfully refreshed from Google Patents.
US3704302A
Expired / Lapsed
US
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Certain cumarin quinazolinones
Assignee: Sumitomo Chemical Co Ltd
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Filing: 1970-02-10
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Granted: 1972-11-28
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Expires: 1990-02-10
Abstract
Abstract COMPOUNDS OF THE FORMULA 7-(R1-N(-R2)-)-2H-CHROMENE WHEREIN R1 AND R2 EACH REPRESENT A HYDROGEN ATOM OR A SUBSTITUTED OR UNSUBSTITUTED ALKYL OR A CYCLOAKLYL GROUP, OR R1 AND R2 CAN FORM A HETEROCYCLIC RING TOGETHER WITH THE NITROGEN ATOM ATTACHED TO THE CUMARIN RESIDUE, AND RING A REPRESENTS A SUBSTITUTED OR UNSUBSTITUTED BENZENE RING OR A NAPHTHALENE RING ARE DISCLOSED. THEY CAN BE EMPLOYED FOR DYEING HYDROPHOBIC FIBERS A CLEAR YELLOW TONE WITH GOOD FASTNESSES. 2-(O=),3-(4-(O=),5,6-(-A-)-3,4-DIHYDROPYRIMIDIN-2-YL),
Inventors
- 👤 Sigeharu Enomoto
- 👤 Katsunobu Sato
- 👤 Goichi Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:46
CPC Classifications
C; C09; C09B; C09B57/00; C09B57/02; D; D06; D06P; D06P1/00; D06P1/0004; D06P1/0012; D06P1/16; Y; Y10; Y10S; Y10S8/00; Y10S8/92; Y10S8/921; Y10S8/922; Y10S8/924
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) | 1975-11-28 | 1976-05-29 | 1976-11-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-11-28 | 1980-05-29 | 1980-11-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-11-28 | 1984-05-29 | 1984-11-28 | $7700.00 | Window Closed / Lapsed |