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US4208183A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for improving the storage stability of indole dyestuffs

Assignee: L'Oréal SA
•
Filing: 1978-05-09
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Granted: 1980-06-17
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Expires: 1998-05-09
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Abstract

Abstract The invention relates to storage-stable dyestuff solutions which can be mixed at the time of use with appropriate carriers. These solutions comprise at least one dihydroxyindole of the formula: ##STR1## in which R 1 and R 2 independently of one another denote hydrogen or methyl, or a cosmetically acceptable salt thereof, in an anhydrous solvent chosen from amongst ethyl, isopropyl and tert.-butyl alcohol, ethylene glycol monomethyl, monoethyl and monobutyl ethers and the acetate of ethylene glycol monoethyl ether.

Inventors

  • 👤 Jean F. Grollier
  • 👤 Chantal Fourcadier

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-27 07:22
CPC Classifications
A; A61; A61K; A61K8/00; A61K8/18; A61K8/30; A61K8/49; A61K8/4906; A61K8/4913; A61K8/492; A61Q; A61Q5/00; A61Q5/10

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 123 words
A process for improving the storage stability of either a dye having the formula: ##STR4## in which R 1 and R 2 , identical or different, are hydrogen or methyl, or a cosmetically acceptable salt of said dye comprising the steps of dissolving at least one of said dye or salt thereof in at least one substantially anhydrous hydroxylic solvent selected from the group consisting of ethyl alcohol, isopropyl alcohol, tert.-butyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, and the acetate of ethylene glycol monoethyl ether, wherein the dye or salt thereof is present in an amount from about 0.1 to 80% by weight, and maintaining said dye in the presence of said anhydrous solvent during storage.
Claim 2
Dependent Claim 123 words
A process for improving the storage stability of either a dye having the formula: ##STR4## in which R 1 and R 2 , identical or different, are hydrogen or methyl, or a cosmetically acceptable salt of said dye comprising the steps of dissolving at least one of said dye or salt thereof in at least one substantially anhydrous hydroxylic solvent selected from the group consisting of ethyl alcohol, isopropyl alcohol, tert.-butyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, and the acetate of ethylene glycol monoethyl ether, wherein the dye or salt thereof is present in an amount from about 0.1 to 80% by weight, and maintaining said dye in the presence of said anhydrous solvent during storage.
Claim 3
Dependent Claim 15 words
The process of claim 1, wherein the dye is in the form of a halide.
Claim 4
Dependent Claim 15 words
The process of claim 1, wherein the dye is in the form of a hydrobromide.
Claim 5
Dependent Claim 10 words
The process of claim 1, wherein the dye is 5,6-dihydroxyindole.
Claim 6
Dependent Claim 11 words
The process of claim 3, wherein the dye is 2,3-dimethyl-5,6-dihydroxyindole hydrobromide.
Claim 7
Dependent Claim 10 words
The process of claim 1, wherein the dye is 2,3-dimethyl-5,6-dihydroxyindole.
Claim 8
Dependent Claim 12 words
The process of claim 1, wherein the anhydrous solvent is ethyl alcohol.
Claim 9
Dependent Claim 19 words
The process of claim 1, wherein the dye is present in an amount from 0.5 to 50% by weight.
Claim 10
Dependent Claim 11 words
The process of claim 1, wherein the dye is 2-methyl-5,6 dihydroxyindole.
Claim 11
Dependent Claim 32 words
The process of claim 1, wherein the anhydrous solvent is selected from the group consisting of ethylene glycol monoethyl ether, ethylene glycol monobutyl ether and the acetate of ethylene glycol monoethyl ether.

References Cited (Backward Citations)

US3194734A Cited
US4013404A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-06-17 1983-12-17 1984-06-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-06-17 1987-12-17 1988-06-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-06-17 1991-12-17 1992-06-17 $7700.00 Window Closed / Lapsed

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