Claims
- 1. A process for preserving the dyeing capacity in an aqueous medium of a dyeing agent consisting of a 5,6-dihydroxyindole, said indole having the formula ##STR10## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, each independently, represent hydrogen or C.sub.1 -C.sub.4 lower alkyl with the proviso that R.sub.1, R.sub.2 and R.sub.3 represent hydrogen when R.sub.4 represents alkyl, said process comprising adjusting the pH of said aqueous medium to a pH.sub.C value of between 5 and 10 by adding thereto a pH regulating agent containing two components (A) and (B), wherein said components (A) and (B) are dipotassium hydrogen phospate and potassium dihydrogen phosphate respectively or triethanolamine and tartaric acid respectively, the weight ratio of said component (A) to said component (B) being greater than 1 and the molar ratio of said component (A) to said component (B) being greater than or equal to 2 and less than 15.
- 2. The process of claim 1 wherein said indole is 5,6-dihydroxyindole.
- 3. The process of claim 1 wherein said indole is selected from the group consisting of 2-methyl-5,6-dihydroxyindole, 3-methyl-5,6-dihydroxyindole, 1-methyl-5,6-dihydroxyindole, 2,3-dimethyl-5,6-dihydroxyindole and 5-methoxy-6-hydroxyindole.
- 4. The process of claim 1 wherein said pH regulating agent containing said components (A) and (B) is present in an amount ranging from 5.times.10.sup.-3 to 50.times.10.sup.-3 moles per 100 g of dyeing composition.
- 5. The process of claim 1 wherein the pH of said aqueous medium ranges from 7 to 9.
- 6. A composition for dyeing keratinous fibers consisting essentially of an aqueous medium containing a dyeing agent consisting of a 5,6-dihydroxyindole having the formula ##STR11## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, each independently, represent hydrogen or C.sub.1 -C.sub.4 lower alkyl with the proviso that R.sub.1, R.sub.2 and R.sub.3 represent hydrogen when R.sub.4 represents alkyl and a pH-regulating agent present in an amount sufficient to adjust the pH of said composition to a pH.sub.C value ranging from 5 to 10, said pH-regulating agent containing two components (A) and (B), wherein said components (A) and (B) are dipotassium hydrogen phosphate and potassium dihydrogen phospate respectively or triethanolamine and tartaric acid respectively, the weight ratio of said component (A) to said component (B) being greater than 1 and the molar ratio of said component (A) to said component (B) being greater than or equal to 2 and less than 15, with the optional presence of 0.5 to 50 percent by weight of a solvent or 0.1 to 50 percent by weight of a surfactant.
- 7. The composition of claim 6 wherein said indole is 5,6-dihydroxyindole.
- 8. The composition of claim 6 wherein said indole is selected from the group consisting of 2-methyl-5,6-dihydroxyindole, 3-methyl-5,6-dihydroxyindole, 1-methyl-5,6-dihydroxyindole, 2,3-dimethyl-5,6-dihydroxyindole and 5-methoxy-6-hydroxyindole.
- 9. The composition of claim 6 wherein said indole is present in an amount ranging from 0.01 to 5 percent by weight based on the total weight of said composition.
- 10. The composition of claim 6 wherein said indole is present in an amount ranging from 0.2 to 1 percent by weight based on the total weight of said composition.
- 11. The composition of claim 6 wherein the solvent is selected from the group consisting of a C.sub.1 -C.sub.4 lower alcohol, ethylene glycol, propylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether and methyl lactate.
- 12. The composition of claim 11 wherein said solvent is present in an amount ranging from 2 to 20 weight percent.
- 13. The composition of claim 6 which also includes a thickening agent present in an amount ranging from 0.1 to 5 percent by weight based on the total weight of said composition.
- 14. The composition of claim 6 which also includes a thickening agent present in an amount ranging from 0.5 to 3 percent by weight based on the total weight of said composition.
- 15. The composition of claim 6 wherein said surfactant includes at least one of a cationic, nonionic, anionic or amphoteric surfactant, or a mixture thereof.
- 16. A process for dyeing keratinous fibers consisting of applying to said fibers the dye composition of claim 6 in an amount effective to dye said fibers, permitting said composition to remain in contact with said fibers for a period of time ranging from 1 to 40 minutes and rinsing said fibers.
- 17. A process for dyeing keratinous fibers consisting of applying to said fibers several times and successively the dye composition of claim 6.
- 18. A process for preserving the dyeing capacity of a dyeing agent in an aqueous medium, said dyeing agent consisting of a 5,6-dihydroxyindole, said indole having the formula ##STR12## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, each independently, represent hydrogen or C.sub.1 -C.sub.4 lower alkyl with the proviso that R.sub.1, R.sub.2 and R.sub.3 represent hydrogen when R.sub.4 represents alkyl, said process comprising adjusting the pH of said aqueous medium to a pH.sub.C value of between 5 and 10 by adding thereto tartaric acid, the weight ratio of said component (A) to said component (B) being greater than 1 and the molar ratio of said component (A) to said component (B) being greater than or equal to 2 and less than 15.
- 19. The process of claim 18 wherein said indole is 5,6-dihydroxyindole.
- 20. The process of claim 18 wherein said indole is selected from the group consisting of 2-methyl-5,6-dihydroxyindole, 3-methyl-5,6-dihydroxyindole, 1-methyl-5,6-dihydroxyindole, 2,3-dimethyl-5,6-dihydroxyindole and 5-methoxy-6-hydroxyindole.
- 21. The process of claim 18 wherein said pH regulating agent containing said components (A) and (B) is present in an amount ranging from 5.times.10.sup.-3 to 50.times.10.sup.-3 moles per 100 g of dyeing composition.
- 22. The process of claim 18 wherein the pH of said aqueous medium ranges from 7 to 9.
- 23. A composition for dyeing keratinous fibers consisting essentially of an aqueous medium containing a dyeing agent consisting of a 5,6-dihydroxyindole having the formula ##STR13## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4, each independently, represent hydrogen or C.sub.1 -C.sub.4 lower alkyl with the proviso that R.sub.1, R.sub.2 and R.sub.3 represent hydrogen when R.sub.4 represents alkyl and
- a pH-regulating agent present in an amount sufficient to adjust the pH of said composition to a pH.sub.C value ranging from 5 to 10, said pH-regulating agent containing two components (A) and (B), said component (A) being triethanolamine and said component (B) being a pH-regulating agent having a dissociation constant, pK.sub.CB, in an aqueous solution at 25.degree. C., of 2<pK.sub.CB .ltoreq.pH.sub.C, the weight ratio of said component (A) to said component (B) being greater than 1 and the molar ratio of said component (A) to said component (B) being greater than or equal to 2 and less than 15, with the optional presence of 0.5 to 50 percent by weight of a solvent or 0.1 to 50 percent weight of a surfactant.
- 24. The composition of claim 23 wherein said indole in 5,6-dihydroxyindole.
- 25. The composition of claim 23 wherein said indole is selected from the group consisting of 2-methyl-5,6-dihydroxyindole, 3-methyl-5,6-dihydroxyindole, 1-methyl-5,6-dihydroxyindole, 2,3-dimethyl-5,6-dihydroxyindole and 5-methoxy-6-hydroxyindole.
- 26. The composition of claim 23 wherein said indole is present in an amount ranging from 0.01 to 5 percent by weight based on the total weight of said composition.
- 27. The composition of claim 23 wherein said indole is present in an amount ranging from 0.2 to 1 percent by weight based on the total weight of said composition.
- 28. The composition of claim 23 wherein said solvent is selected from the group consisting of a C.sub.1 -C.sub.4 lower alcohol, ethylene glycol, propylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether and methyl lactate.
- 29. The composition of claim 28 wherein said solvent is present in an amount ranging from 2 to 20 percent.
- 30. The composition of claim 23 which also includes a thickening agent present in an amount ranging from 0.1 to 5 percent by weight based on the total weight of said composition.
- 31. The composition of claim 23 which also includes a thickening agent present in an amount ranging from 0.5 to 3 percent by weight based on the total weight of said composition.
- 32. The composition of claim 23 which also includes at least one of a cationic, nonionic, anionic or amphoteric surfactant, or a mixture thereof.
- 33. A process for dyeing keratinous fibers consisting of applying to said fibers the dye composition of claim 23 in an amount effective to dye said fibers, permitting said composition to remain in contact with said fibers for a period of time ranging from 1 to 40 minutes and rinsing said fibers.
- 34. A process for dyeing keratinous fibers consisting of applying to said fibers several times and successively the dye composition of claim 23.
Priority Claims (1)
Number |
Date |
Country |
Kind |
87196 |
Apr 1988 |
LUX |
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Parent Case Info
This is a continuation of application Ser. No. 08/041,987, filed Apr. 2, 1993, now abandoned, which is a continuation of application Ser. No. 07/706,194 filed May 28, 1991, now abandoned, which is a continuation of application Ser. No. 07/336,492 filed Apr. 12, 1989, now abandoned.
US Referenced Citations (11)
Continuations (3)
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Number |
Date |
Country |
Parent |
41987 |
Apr 1993 |
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Parent |
706194 |
May 1991 |
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Parent |
336492 |
Apr 1989 |
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