US3597424A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gold-yellow to red-yellow cationic dyes and their preparation
Assignee: EIDP Inc
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Filing: 1968-11-07
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Granted: 1971-08-03
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Expires: 1988-11-07
Abstract
Abstract A PROCESS FOR PREPARING GOLD-YELLOW TO RED-YELLOW CATIONIC DYES BY CONDENSING 1,3,3-TRIMETHYL-2-METHYLENE INDOLINE-OMEGA-ALDEHYDE WITH A TETRAHYDROQUINOXALINE IN AN ALCOHOLIC SOLVENT IN THE PRESENCE OF A MINERAL ACID CATALYST, AND THE DYES DERIVED THEREFROM.
Inventors
- 👤 Frank Ray Hunter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:46
CPC Classifications
C; C09; C09B; C09B23/00; C09B23/10; C09B23/105; Y; Y10; Y10S; Y10S8/00; Y10S8/92; Y10S8/927
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) | 1974-08-02 | 1975-02-01 | 1975-08-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-02 | 1979-02-01 | 1979-08-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-02 | 1983-02-01 | 1983-08-03 | $7700.00 | Window Closed / Lapsed |