Patent US3772268A successfully refreshed from Google Patents.
US3772268A
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US
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Purification of copper contaminated dye compounds using di(hydroxyalkyl)sulfides
Assignee: Novartis Corp
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Filing: 1971-12-20
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Granted: 1973-11-13
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Expires: 1991-12-20
Abstract
Abstract COPPER IMPURITIES IN DYE COMPOUNDS ARE REMOVED BY CONTACTING SUCH A CONTAMINATED COMPOUND WITH A DI(HYDROXYALKYL)SULFIDE AND RECOVERING THE DYE SUBSTANTIALLY FREE OF COPPER. THE PROCESS CAN BE EMPLOYED IN CONJUNCTION WITH THE SYNTHESIS OF CAYNO SUBSTITUTED DYES BY CYAMIDE DISPLACEMENT REACTIONS WHICH EMPLOY COPPER AS A CATALYST. THE PURIFICATION PROCESS RESULTS IN CERTAIN ADDITION COMPOUNDS OF A CUPROUS OF CUPRIC SALT AND THE DI(HYDROXYALKYL)SULFIDE.
Inventors
- 👤 R Giles
- 👤 J Straley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 16:19
CPC Classifications
C; C09; C09B; C09B43/00; C09B43/40; C09B43/42; C09B29/00; C09B29/06; C09B29/08; C09B29/0805; C09B29/0807; C09B29/0809; C09B67/00; C09B67/0096
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |