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Di-p-toluenesulfonic acid salt of N-ethyl-N-methoxyethyl-3-methyl 1,4 benzenediamine

Assignee: Eastman Kodak Co
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Filing: 1974-01-23
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Granted: 1975-09-23
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Expires: 1994-01-23
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Abstract

Abstract The p-toluenesulfonic acid salts of certain p-phenylenediamine color developing agents have been found to possess extraordinarily and unexpectedly high solubility in aqueous alkaline solution. Thus, extremely concentrated solutions of these materials can be prepared to provide developer ''''concentrates'''' which are extremely economical to ship and working developer solutions which possess abnormally high developing agent concentrations and which are therefore capable of producing unusually high dye density levels in very short periods of time. Specifically preferred among these pphenylenediamine salts are the di-p-toluenesulfonic acid salts of 3-alkyl and 3-alkoxy N-alkyl-N-alkoxyalkyl-p-phenylenediamine developing agents.

Inventors

  • 👤 Dietmar Schellenberg
  • 👤 Richard L Bent

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 15:06
CPC Classifications
G; G03; G03C; G03C7/00; G03C7/30; G03C7/407; G03C7/413; G03C7/4136

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 5 words
A COMPOUND OF THE FORMULA
Claim 2
Dependent Claim 5 words
A COMPOUND OF THE FORMULA

References Cited (Backward Citations)

US3656950A Cited
US3658525A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-09-22 1979-03-24 1979-09-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-09-22 1983-03-24 1983-09-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-09-22 1987-03-24 1987-09-23 $7700.00 Window Closed / Lapsed

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