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US3772268A Expired / Lapsed US ⏱️ 0.0 years remaining

Purification of copper contaminated dye compounds using di(hydroxyalkyl)sulfides

Assignee: Novartis Corp
•
Filing: 1971-12-20
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Granted: 1973-11-13
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Expires: 1991-12-20
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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 15:13
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

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