Patent Application
20200306160
The present invention relates to a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, using one or more particular 2-azo(benz)imidazolium dyes and one or more fluorescent dyes.
The present invention also relates to a cosmetic composition comprising the dyes defined above, and also to a multi-compartment device containing said dyes.
The present invention also relates to the use of said dyes for dyeing light keratin fibres, especially human keratin fibres such as the hair, in chestnut-brown, dark chestnut-brown, brown, brown with a glint, or even black, without using an additional dye other than those defined above.
Many people have sought for a long time to modify the colour of their hair and in particular to mask their grey hair.
It is especially known practice to dye keratin fibres, in particular human keratin fibres, with dye compositions containing oxidation dye precursors, which are generally known as oxidation bases. These oxidation bases are colourless or weakly coloured compounds, which, when combined with oxidizing products, may give rise to coloured compounds via a process of oxidative condensation.
The shades obtained with these oxidation bases may be modified by combining them with couplers or colour modifiers. The variety of molecules used in the oxidation bases and couplers allows a wide range of colours to be obtained.
Another well-known method consists in obtaining semi-permanent dyeing by applying to the keratin fibres direct dyes, which are coloured and colouring molecules that have affinity for said fibres.
The direct dyes conventionally used are chosen from nitrobenzene, anthraquinone, nitropyridine, azo, xanthene, acridine, azine and triarylmethane direct dyes. The chemical species may be nonionic, anionic (acidic dyes) or cationic (basic dyes). The direct dyes may also be natural dyes.
Conventional direct dyeing processes consist in applying to keratin fibres dye compositions comprising direct dyes. After application, a leave-on time is observed so as to allow the dye molecules to penetrate by diffusion into the fibres. On conclusion of the process, the fibres are rinsed.
In contrast with oxidation dyeing, these direct dyeing processes have a tendency to better protect the integrity of the fibres. The resulting colourings are generally chromatic, but, however, are only semi-temporary. The nature of the interactions that bind the direct dyes to the keratin fibres and their desorption from the surface and/or the core of the fibre are responsible for their weak dyeing power.
Although a wide range of colours is currently accessible, it generally proves necessary to combine three dyes of complementary colours—trichromatic principle—in order to obtain a natural shade (see, for example, WO 95/15144 and WO 95/01772). This tripartite combination does not, however, show good persistence with respect to repeated shampooing. It generally, or even systematically, induces an unaesthetic changing of the colour, which the consumer finds dissuasive.
Thus, these colourings may furthermore not be sufficiently fast in the face of external agents such as light or perspiration.
Thus, there is a real need to develop processes for the direct dyeing of keratin fibres, in particular of human keratin fibres such as the hair, which do not have the drawbacks mentioned above, i.e. which make it possible especially to lead to natural colourings that have good properties, especially in terms of chromaticity, power, intensity, sheen and selectivity, and which are persistent with respect to shampooing.
Another aim of the invention is thus to be able to dye light keratin fibres efficiently in chestnut-brown, dark chestnut-brown, brown or brown with a glint or even black, by mixing direct dyes, and preferably only two types of direct dye.
The Applicant has found, surprisingly, that a process for dyeing keratin fibres using one or more particular 2-azo(benz)imidazolium dyes and one or more specific fluorescent dyes makes it possible to achieve the objectives mentioned above; especially to lead to natural chestnut-brown, dark chestnut-brown, brown, brown with a glint or even black colourings, which are not only powerful and shiny, but also shampoo-resistant.
One subject of the present invention is especially a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, comprising the application to said keratin fibres of the following ingredients:
(a) one or more 2-azo(benz)imidazolium dyes chosen from the compounds of formula (I) below, the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof,
in which formula (I):
R, which may be identical or different, represent an optionally substituted linear or branched C1 to C6 alkyl radical;
n denotes an integer equal to 0, 1 or 2,
when n is equal to 2, the two radicals R may form, with the carbon atoms to which they are attached, an optionally substituted, saturated or unsaturated 6-membered ring, preferably benzo,
R1 and R2, which may be identical or different, represent an optionally substituted, saturated or unsaturated, linear or branched C1 to C6 alkyl radical;
R3, which may be identical or different, represent:
m denotes an integer ranging from 0 to 4,
when m is equal to 2, 3 or 4, two adjacent radicals R3 may form, with the carbon atoms to which they are attached, a 6-membered aromatic ring, preferably benzo, optionally substituted with one or more hydroxyl or amino groups,
R4 represents:
in which:
Y− represents an anionic counterion or a mixture of organic or inorganic anions which ensure the electrical neutrality of the compounds of formula (I); and (b) one or more fluorescent dyes; said fluorescent dyes being direct dyes chosen from cyanin dyes, styryl/hemicyanin dyes, naphthalimide dyes, and mixtures thereof; it being understood that the 2-azo(benz)imidazolium dye(s) (a) and the fluorescent dye(s) (b) are applied to said keratin fibres together or sequentially.
Another subject of the invention is a cosmetic composition comprising: (a) one or more 2-azo(benz)imidazolium dyes chosen from the compounds of formula (I), as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof; and (b) one or more fluorescent dyes, as defined previously.
The combination of particular 2-azo(benz)imidazolium dye(s) and of fluorescent dye(s) makes it possible especially to obtain natural colourings that have good dyeing properties, especially in terms of chromaticity, power, intensity, sheen and selectivity.
Furthermore, the process and the composition according to the invention make it possible to dye light keratin materials efficiently in chestnut-brown, dark chestnut-brown, brown, brown with a glint or even black, by mixing direct dyes, and in particular only the dyes (a) and (b) as defined previously, without the need to use an additional (or complementary) dye other than (a) or (b).
Moreover, the colourings obtained by means of the process and the composition according to the invention show good resistance to the various attacking factors to which the hair may be subjected, such as light, bad weather, washing and perspiration. They are in particular persistent with respect to shampooing, especially after at least three shampoo washes.
A subject of the present invention is also a multi-compartment device comprising a first compartment containing one or more 2-azo(benz)imidazolium dyes (a) chosen from the compounds of formula (I) as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof, and a second compartment containing one or more fluorescent dyes (b) as defined previously.
Another subject of the invention is the use of fluorescent dye(s), as defined previously, combined with 2-azo(benz)imidazolium dye(s) chosen from the compounds of formula (I), as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof, for the dyeing of light keratin fibres, especially human keratin fibres such as the hair, in chestnut-brown, dark chestnut-brown, brown, brown with a glint or even black, without using an additional dye other than (a) or (b).
Other subjects, characteristics, aspects and advantages of the invention will emerge even more clearly on reading the description and the examples that follow.
For the purposes of the present invention and unless otherwise indicated:
(a) 2-Azo(benz)imidazolium Dyes
The process for dyeing keratin fibres and the cosmetic composition according to the present invention use, or comprise, (a) one or more 2-azo(benz)imidazolium dyes chosen from the compounds of formula (I), as defined previously, the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof.
In particular, the dyes of formula (I) are blue, violet or green, and dull or chromatic.
Preferably, the 2-azo(benz)imidazolium dye(s) chosen from the compounds of formula (I) are dyes which absorb light in the blue-violet range, preferably in the blue range.
Preferably, n is equal to 0 or 2. According to one particular embodiment, n is 0. According to another embodiment, n is 1.
According to another particular embodiment, n is 2. More particularly, according to this embodiment, the two radicals R form, with the carbon atoms to which they are attached, an optionally substituted, saturated or unsaturated, 6-membered ring, preferably an optionally substituted, unsaturated 6-membered ring such as benzo, and more preferentially an unsubstituted, unsaturated 6-membered ring such as unsubstituted benzo.
Preferably, R, which may be identical or different, represent an unsubstituted linear or branched C1 to C3 alkyl radical.
Preferably, R1 and R2 are identical and represent an unsubstituted C1 to C2 alkyl radical, and more preferentially a methyl radical.
Preferably:
R4 represents a radical —NR5R6 in which R5 and R6, which may be identical or different, represent:
more preferentially a saturated 5-membered ring, such as a piperidine ring; and more preferentially, R4 represents a radical —NR5R6, in which R5 and R6, which may be identical or different, represent: i) a hydrogen atom, ii) a (C1-C4)alkyl radical, iii) a phenyl radical which is substituted, in particular in the para position, with a group chosen from amino and (di)(C1-C4)alkylamino, or R5 and R6 form, together with the nitrogen atom that bears them, a saturated, 4- to 8-membered and preferably 5- to 6-membered heterocycle, and even more preferentially a saturated 5-membered ring, such as piperidino.
According to a first preferred embodiment:
n represents an integer equal to 0 or 2,
when n is equal to 2, the two radicals R form, with the carbon atoms to which they are attached, an optionally substituted, saturated or unsaturated, 6-membered ring, preferably an optionally substituted, unsaturated 6-membered ring, and more preferentially an unsubstituted, unsaturated 6-membered ring, and
R1 and R2 are identical and represent a methyl radical.
According to a second preferred embodiment:
n represents an integer equal to 0 or 2,
when n is equal to 2, the two radicals R form, with the carbon atoms to which they are attached, an optionally substituted, saturated or unsaturated, 6-membered ring, preferably an optionally substituted, unsaturated 6-membered ring, and more preferentially an unsubstituted, unsaturated 6-membered ring,
R1 and R2 are identical and represent a methyl radical, and
R4 represents a radical —NR5R6 in which R5 and R6, which may be identical or different, represent, independently of each other:
According to a third particular embodiment, R4 represents a radical —NR5R6 in which R5 and R6, which may be identical or different, represent:
According to a fourth preferred embodiment:
n represents an integer equal to 0 or 2,
when n is equal to 2, the two radicals R form, with the carbon atoms to which they are attached, an optionally substituted, saturated or unsaturated, 6-membered ring, preferably an optionally substituted, unsaturated 6-membered ring, in particular benzo, and more preferentially unsubstituted benzo,
R1 and R2 are identical and represent a methyl radical,
According to a fifth preferred embodiment:
n represents an integer equal to 0 or 2,
when n is equal to 2, the two radicals R form, with the carbon atoms to which they are attached, an optionally substituted, saturated or unsaturated, 6-membered ring, preferably an optionally substituted, unsaturated 6-membered ring, in particular benzo, and more preferentially unsubstituted benzo,
R1 and R2 are identical and represent a methyl radical, and
R4 represents a radical of formula (II) as defined previously.
Preferably, R3, which may be identical or different, represent, independently of each other:
a hydrogen atom,
a methyl radical,
a hydroxyl radical,
a nitro radical,
an amino radical,
a chlorine atom,
a linear or branched C1 to C4 and preferably C1 to C2 alkoxy radical, and more preferentially a methoxy radical,
when R3 is borne by the carbon located ortho to R4, R3 may form with R4 a saturated or unsaturated, 5- or 6-membered, optionally substituted and preferably unsubstituted heterocycle, and
when m is equal to 2, 3 or 4, two adjacent radicals R3 may form, with the carbon atoms to which they are attached, an unsubstituted 6-membered aromatic ring, preferably benzo.
Y− denotes a cosmetically acceptable anionic counterion or mixture of anions intended to ensure the electrical neutrality of the compounds of formula (I).
The term “anionic counterion or mixture of anions intended to ensure the electrical neutrality of the compounds of formula (I)” means an anion or an anionic group derived from an organic or mineral acid salt, which counterbalances the cationic charge of the compound.
Preferably, Y− is chosen from i) halides such as chloride, bromide, fluoride or iodide; ii) hydroxides; iii) sulfates; iv) hydrogen sulfates; v) linear or branched C1 to C6 alkyl sulfates, such as the methylsulfate or ethylsulfate ion; vi) carbonates and hydrogen carbonates; vii) carboxylic acid salts such as formate, acetate, citrate, tartrate and oxalate; viii) linear or branched C1-C6 alkylsulfonates, such as the methylsulfonate ion; ix) arylsulfonates for which the aryl part, preferably phenyl, is optionally substituted with one or more C1 to C4 alkyl radicals, for instance 4-tolylsulfonate; x) alkylsulfonyls such as mesylate; xi) the perchlorate ion; and mixtures thereof.
Y−, derived from an organic or mineral acid salt, ensures the electrical neutrality of the molecule; thus, it is understood that when the anion comprises several anionic charges, then the same anion may serve for the electrical neutrality of several cationic groups in the same molecule or else may serve for the electrical neutrality of several molecules.
More preferentially, Y− is chosen from halides, sulfates, acetate and the perchlorate ion, and mixtures thereof.
The compounds of formula (I) may also be in the form of solvates, for example a hydrate or a solvate of a linear or branched alcohol such as ethanol or isopropanol.
Preferably, the 2-azo(benz)imidazolium dye(s) are chosen from the following compounds, the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof:
Y− being as defined previously.
Preferably, the 2-azo(benz)imidazolium dye(s) are chosen from compounds (2), (4) and (9) defined above.
More preferentially, the 2-azo(benz)imidazolium dye(s) are chosen from the following compounds, the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof:
According to a particularly preferred embodiment, the 2-azo(benz)imidazolium compound(s) are chosen from the compounds of formula (I) in which:
n denotes an integer equal to 0 or 2,
when n is equal to 2, the two radicals R form, with the carbon atoms to which they are attached, an unsubstituted benzo ring,
R1 and R2 are identical and represent a methyl radical,
m is equal to 0,
R4 represents a radical —NR5R6 in which R5 and R6, which may be identical or different, represent, independently of each other:
Y− is as defined previously.
Preferably, the 2-azo(benz)imidazolium dye(s) are chosen from compounds (2a), (4a), (9a), (13a) and (37a), as defined previously, the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the solvates thereof, and mixtures thereof.
(b) Fluorescent Dyes
The process for dyeing keratin fibres and the composition according to the present invention also use, or comprise, (b) one or more fluorescent dyes; said fluorescent dyes being direct dyes chosen from cyanin dyes, styryl/hemicyanin dyes, naphthalimide dyes, and mixtures thereof.
More particularly, the fluorescent dye(s) of the invention are other than fluorescent dyes comprising a disulfide bond. More preferentially, the fluorescent dye(s) of the invention are direct dyes and do not comprise a bond containing contiguous identical heteroatoms.
Mention may also be made of the fluorescent dyes described in EP 1 133 975, WO 03/029 359, EP 860 636, WO 95/01772, WO 95/15144, EP 714 954 and those listed in the encyclopaedia The chemistry of synthetic dyes by K. Venkataraman, 1952, Academic Press, vol. 1 to 7, in Kirk Othmer's encyclopaedia Chemical Technology, in the chapter “Dyes and Dye Intermediates”, 1993, Wiley and Sons, and in various chapters of Ullmann's Encyclopedia of Industrial Chemistry 7th edition, Wiley and Sons, especially in Ullmann's Encyclopedia of Industrial Chemistry in the chapter “Fluorescent Dyes”, 2005, Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 10.1002/143560007.a11_279; in The Handbook—A Guide to Fluorescent Probes and Labeling Technologies, 10th Ed Molecular Probes/Invitrogen—Oregon 2005 circulated by Internet or in the preceding printed editions.
Preferably, the fluorescent dye(s) of the invention are cationic.
More preferentially, the fluorescent dyes are direct and cationic; and better still, the fluorescent dye(s) (b) are chosen from styryl or hemicyanin cationic dyes.
Better still, the fluorescent dyes of the invention absorb light in the yellow, orange and red range, preferably in the absorption wavelength abs between 400 nm and 500 nm inclusive.
According to one variant, the fluorescent dyes of the invention contain at least one cationic radical borne by, or included in, at least one of the fluorescent chromophores.
Preferably, the cationic radical is a quaternary ammonium; better still, the cationic charge is endocyclic.
These cationic radicals are, for example, a cationic radical:
According to a preferred variant of the invention, the fluorescent dyes of the invention bear at least one cationic chromophore and comprise at least one cationic ammonium radical such as polymethine chromophores chosen from formulae (III) and (IV) below:
W+—[C(Rc)═C(Rd)]m′—Ar′-(*)Q− (III)
Ar—[C(Rd)═C(Rc)]m′—W′+-(*)Q−(IV),
in which formulae (III) and (IV):
Preferably, W+ or W′+ is an imidazolium, pyridinium, benzimidazolium, pyrazolium, benzothiazolium or quinolinium radical optionally substituted with one or more identical or different C1-C4 alkyl radicals.
According to a particularly preferred embodiment of the invention, the fluorescent chromophore(s) of the dye (III) or (IV) are those defined previously with m′=1, Ar representing a phenyl group substituted para to the styryl group —C(Rd)═C(Rc)— with a (di)(hydroxy)(C1-C6)(alkyl)amino group such as dihydroxy(C1-C4)alkylamino, and W′+ representing an imidazolium or pyridinium group, preferentially ortho- or para-pyridinium.
According to another preferred variant of the invention, the fluorescent chromophore(s) of the dyes are cationic and comprise at least one quaternary ammonium radical such as a naphthimidyl bearing a cationic exocyclic charge of formula (IIIa) or (IVa):
in which formulae (IIIa) and (IVa) Re, Rf, Rg and Rh, which may be identical or different, represent a hydrogen atom or a (C1-C6)alkyl group which is optionally substituted, preferentially with a di(C1-C6)alkylamino or tri(C1-C6)alkylammonium group such as trimethylammonium.
According to a particular embodiment, the fluorescent dye(s) of the invention (b) are chosen from those of formula (V), (VI) or (VII) below, and also the organic or mineral, acid or base salts thereof, the optical isomers, geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates:
in which formulae (V), (VI) and (VII):
or alternatively two adjacent radicals Rc and Rd borne by the same nitrogen atom together form an optionally substituted heterocyclic or optionally substituted heteroaryl group;
represents a (hetero)aryl group fused to the phenyl ring; or alternatively is absent from the phenyl; preferentially, when the ring is present, the ring is a benzo;
According to one embodiment, the fluorescent dyes of the invention are of formula (V) as defined previously.
According to a preferred embodiment, the fluorescent dye(s) of the invention are chosen from the styryl dyes of formula (VIII) below, and also the organic or mineral, acid or base salts thereof, the optical isomers, geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates:
in which formula (VIII) G, G1, Ra, R′a, R″a, Rb, R′b, R″b, Ri, R′i, R1, R2 and m are as defined previously for (V).
In particular, the dye(s) of the invention are chosen from those of formula (VIII) for which:
represents an aryl or heteroaryl group fused to the phenyl ring; or alternatively is absent from the phenyl ring; preferentially, when the ring is present, the ring is a benzo;
Preferably, the fluorescent dye(s) (b) of the invention are chosen from the styryl dyes of formula (IX) below, and also the organic or mineral, acid or base salts thereof, the optical isomers, geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates:
in which formula (IX) G, G1, Ra, R′a, Rb, R′b and m are as defined previously.
According to a particular embodiment, the group G is in the para position relative to the —CH═CH— group, i.e. in position 4′ of the phenyl group. According to another particular embodiment, the group G is in the ortho position relative to the —CH═CH— group, i.e. in position 2′ of the phenyl group. According to one embodiment, the —CH═CH— group is in the para position of the pyridinium group, i.e. in position 4.
According to another advantageous variant, the —CH═CH— group is in the ortho position of the pyridinium group, i.e. in position 2.
According to a preferred mode of the invention, the fluorescent dye(s) of the invention are chosen from the compounds of formulae (X) and (XI) below, and also the organic or mineral, acid or base salts thereof, the optical isomers, geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates:
in which formulae (X) and (XI):
in particular, R10 and R11, which may be identical or different, represent a hydrogen atom or a (C1-C6)alkyl group substituted with one or more hydroxyl, cyano or (C1-C3)alkylcarbonyl groups such as hydroxyethyl;
According to a first embodiment of the invention, the fluorescent dye(s) (b) are of formula (X) with:
and also the organic or mineral, acid or base salts thereof, the optical isomers, geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates.
According to a second embodiment, the fluorescent dye(s) (b) are of formula (XI) with:
and also the organic or mineral, acid or base salts thereof, the geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates.
Preferably, the fluorescent dye(s) (b) are chosen from those of formulae (X′) and (XI′) below:
in which formulae (X′) and (XI′) R5, R7, R8 and m are as defined previously for (X) and (XI), in particular:
According to this embodiment, the fluorescent dye(s) (b) are preferably chosen from those of formula (X′) or (XI′) with:
and
and also the organic or mineral, acid or base salts thereof, the geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates.
According to a yet another preferred mode of the invention, the fluorescent dye(s) (b) of the invention are chosen from the compounds of formulae (XII) and (XIII) below, and also the organic or mineral, acid or base salts thereof, the optical isomers, geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates:
in which formulae (XII) and (XIII):
in particular, R10 and R11, which may be identical or different, represent a hydrogen atom or a (C1-C6)alkyl group optionally substituted with one or more hydroxyl, cyano or (C1-C3)alkylcarbonyl groups such as methyl, ethyl, butyl, isobutyl, cyanoethyl, methylcarbonylethyl, or hydroxyethyl;
According to one embodiment of the invention, the fluorescent dye(s) (b) are of formula (XII) with:
and also the organic or mineral, acid or base salts thereof, the optical isomers, geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates.
According to another embodiment, the fluorescent dye(s) (b) are of formula (XIII) with:
and also the organic or mineral, acid or base salts thereof, the geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates.
More particularly, the fluorescent dye(s) (b) of the invention are chosen from those of formulae (XII′) and (XIII′) below:
in which formulae (XII′) and (XIII′) R5, R7, R8 and m are as defined previously for (X) and (XI), in particular:
According to one embodiment, the fluorescent dye(s) (b) of the invention are of formula (XII′) or (XIII′) with:
and also the organic or mineral, acid or base salts thereof, the geometrical isomers and tautomers thereof, and the solvates thereof such as hydrates.
More particularly, the fluorescent dye(s) (b) of the invention are chosen from those of formula (V), (VIII) or (IX) as defined previously in which G represents a hydrogen atom.
More particularly, the fluorescent dye(s) (b) of the invention are chosen from those of formulae (XIV) and (XV) below:
in which formulae (XIV) and (XV) R5, R7, R8 and m are as defined previously for (X) and (XI), in particular:
More preferentially, the fluorescent dye(s) (b) of the invention are chosen from the following compounds, the geometrical isomers thereof, the tautomers thereof, the solvates thereof and mixtures thereof:
with Y and Q+ as defined previously.
The Oxidizing Agents
The process for dyeing keratin fibres and the cosmetic composition according to the present invention may also optionally use, or comprise, one or more oxidizing agents.
Preferably, the oxidizing agent(s) are chosen from chemical oxidizing agents.
The term “chemical oxidizing agent” means an oxidizing agent other than atmospheric oxygen.
More particularly, the chemical oxidizing agent(s) are chosen from hydrogen peroxide, hydrogen peroxide-generating systems, urea peroxide, alkali metal bromates or ferricyanides, peroxygenated salts, for instance persulfates, perborates, peracids and precursors thereof and percarbonates of alkali metals or alkaline-earth metals, and mixtures thereof.
Preferably, the chemical oxidizing agent(s) are chosen from hydrogen peroxide and hydrogen peroxide-generating systems.
According to a preferred embodiment, the hydrogen peroxide-generating system(s) are chosen from urea peroxide, polymeric complexes that can release hydrogen peroxide, chosen from polyvinylpyrrolidone/H2O2; oxidases; perborates; and percarbonates.
Preferably, the chemical oxidizing agent is hydrogen peroxide, and more preferentially aqueous hydrogen peroxide solution.
The chemical oxidizing agent(s) are advantageously applied in the form of an aqueous solution of which the content of chemical oxidizing agents is preferably between 0.05% and 5% by weight and more preferentially between 0.1% and 2% by weight, relative to the total weight of the aqueous solution.
According to a preferred embodiment of the invention, the dyeing process does not use any oxidizing agent.
According to this preferred embodiment of the invention, the cosmetic composition comprising ingredients (a) and (b) does not comprise any oxidizing agent.
The Reducing Agents
The process for dyeing keratin fibres and the cosmetic composition according to the present invention may also optionally use, or comprise, one or more reducing agents.
The reducing agent(s) that are useful for the present invention are advantageously chosen from the compounds of formula (XVI) below, and also the addition salts thereof and mixtures thereof:
H(X)q(R10)t (XVI)
in which formula (XVI):
Preferably, the reducing agent(s) are chosen from thioglycolic acid, thiolactic acid, glyceryl monothioglycolate, cysteamine, N-acetylcysteamine, N-propionylcysteamine, cysteine, N-acetylcysteine, thiomalic acid, pantetheine, 2,3-dimercaptosuccinic acid, N-(mercaptoalkyl)-ω-hydroxyalkylamides, N-mono- or N,N-dialkylmercapto-4-butyramides, aminomercaptoalkylamides, N-(mercaptoalkyl)succinamic acid and N-(mercaptoalkyl)succinimide derivatives, alkylamino mercaptoalkylamides, the azeotropic mixture of 2-hydroxypropyl thioglyconate and of (2-hydroxy-1-methyl)ethyl thioglycolate, mercaptoalkylaminoamides, N-mercaptoalkylalkanediamides and formamidinesulfinic acid derivatives, salts thereof, and mixtures thereof.
Preferably, the reducing agent(s) are also chosen from salts such as sodium sulfite, sodium dithionite or sodium thiosulfate, and mixtures thereof.
The chemical reducing agent(s) are advantageously applied in the form of an aqueous solution of which the content of chemical reducing agents is preferably between 0.01% and 10% by weight and more preferentially between 0.1% and 5% by weight, relative to the total weight of the aqueous solution.
According to a preferred embodiment of the invention, the dyeing process does not use any reducing agent.
According to this preferred embodiment of the invention, the cosmetic composition comprising ingredients (a) and (b) does not comprise any reducing agent.
The Cosmetic Medium and the Solvents
The 2-azo(benz)imidazolium dye(s) of formula (I), as defined previously, and (b) the fluorescent dye(s), as defined previously, and also, when they are present, the oxidizing agent(s) and/or the reducing agent(s), may be dissolved beforehand before being applied to the keratin fibres.
In other words, the ingredients used in the dyeing process of the present invention may be present in one or more compositions.
The composition(s) comprising the ingredients according to the present invention are cosmetic compositions, i.e. they are preferably aqueous. Besides water, they may comprise one or more organic solvents, or mixtures thereof.
Examples of organic solvents that may be mentioned include linear or branched C2 to C4 alkanols, such as ethanol and isopropanol; glycerol; polyols and polyol ethers, for instance 2-butoxyethanol, propylene glycol, hexylene glycol, dipropylene glycol, propylene glycol monomethyl ether, diethylene glycol monomethyl ether and monoethyl ether, and also aromatic alcohols or ethers, for instance benzyl alcohol or phenoxyethanol, and mixtures thereof.
The pH
The pH of the composition(s) used in the dyeing process of the invention and of the composition of the invention comprising ingredients (a) and (b) is preferably between 2 and 12 and more preferentially between 3 and 11. It may be adjusted to the desired value by means of acidifying or basifying agents usually used in the dyeing of keratin fibres, or alternatively using standard buffer systems.
The pH of the composition which comprises ingredients (a) and (b) and that of the composition(s) used in the dyeing process of the invention is preferably between 6 and 11 inclusive, more preferentially between 7 and 10 and better still between 7.5 and 9.5, such as between 9 and 9.5.
Among the acidifying agents as defined previously, mention may be made, by way of example, of mineral or organic acids, for instance hydrochloric acid, orthophosphoric acid or sulfuric acid, carboxylic acids, for instance acetic acid, tartaric acid, citric acid and lactic acid, and sulfonic acids.
The alkaline agent(s) may be chosen especially from mineral, organic or hybrid alkaline agents, and mixtures thereof.
The mineral alkaline agent(s) are preferably chosen from ammonia, alkaline carbonates or bicarbonates such as ammonium, sodium or potassium carbonates or bicarbonates, ammonium, sodium or potassium hydroxides, or mixtures thereof.
The organic alkaline agent(s) are preferably chosen from organic amines with a pKb at 25° C. of less than 12, preferably of less than 10 and more advantageously still of less than 6. It should be noted that it concerns the pKb corresponding to the function having the highest basicity. In addition, the organic amines do not comprise any alkyl or alkenyl fatty chain comprising more than ten carbon atoms.
The organic alkaline agent(s) are preferably chosen from alkanolamines, in particular mono-, di- or tri-hydroxy(C1-C6)alkylamine, such as triethanolamine, oxyethylenated and/or oxypropylenated ethylenediamines, amino acids, polyamines of formula (XVII) below, and mixtures thereof:
in which formula (XVII) W is a divalent C1-C6 alkylene radical optionally substituted with one or more hydroxyl groups or a C1-C6 alkyl radical, and/or optionally interrupted with one or more heteroatoms such as O, or —NRu; Rx, Ry, Rz, Rt and Ru, which may be identical or different, represent a hydrogen atom or a C1-C6 alkyl, C1-C6 hydroxyalkyl or C1-C6 aminoalkyl radical.
Examples of amines of formula (XVII) that may be mentioned include 1,3-diaminopropane, 1,3-diamino-2-propanol, spermine and spermidine.
The term “alkanolamine” means an organic amine comprising a primary, secondary or tertiary amine function, and one or more linear or branched C1 to C8 alkyl groups bearing one or more hydroxyl radicals.
Organic amines chosen from alkanolamines such as monoalkanolamines, dialkanolamines or trialkanolamines comprising one to three identical or different C1 to C4 hydroxyalkyl radicals are in particular suitable for performing the invention.
Among the compounds of this type, mention may be made of monoethanolamine (MEA), diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, N,N-dimethylethanolamine, 2-amino-2-methyl-1-propanol, triisopropanolamine, 2-amino-2-methyl-1,3-propanediol, 3-amino-1,2-propanediol, 3-dimethylamino-1,2-propanediol and tris(hydroxymethyl)aminomethane.
More particularly, the amino acids that may be used are of natural or synthetic origin, in their L, D or racemic form, and comprise at least one acid function chosen more particularly from carboxylic acid, sulfonic acid, phosphonic acid and phosphoric acid functions. The amino acids may be in neutral or ionic form.
As amino acids that may be used in the present invention, mention may be made in particular of aspartic acid, glutamic acid, alanine, arginine, omithine, citrulline, asparagine, camitine, cysteine, glutamine, glycine, histidine, lysine, isoleucine, leucine, methionine, N-phenylalanine, proline, serine, taurine, threonine, tryptophan, tyrosine and valine.
Advantageously, the amino acids are basic amino acids comprising an additional amine function optionally included in a ring or in a ureido function.
Such basic amino acids are preferably chosen from those corresponding to formula (XVIII) below, and also salts thereof:
R—CH2—CH(NH2)—C(O)—OH (XVIII)
in which formula (XVIII) R represents a group chosen from imidazolyl, preferably imidazolyl-4-yl; aminopropyl; aminoethyl; —(CH2)2N(H)—C(O)—NH2; and —(CH2)2—N(H)—C(NH)—NH2.
The compounds corresponding to formula (XVIII) are histidine, lysine, arginine, omithine and citrulline.
The organic amine may also be chosen from organic amines of heterocyclic type. Besides histidine that has already been mentioned in the amino acids, mention may in particular be made of pyridine, piperidine, imidazole, triazole, tetrazole and benzimidazole.
The organic amine may also be chosen from amino acid dipeptides. As amino acid dipeptides that may be used in the present invention, mention may be made especially of camosine, anserine and balenine.
The organic amine may also be chosen from compounds comprising a guanidine function. As amines of this type that may be used in the present invention, besides arginine, which has already been mentioned as an amino acid, mention may be made in particular of creatine, creatinine, 1,1-dimethylguanidine, 1,1-diethylguanidine, glycocyamine, metformin, agmatine, n-amidinoalanine, 3-guanidinopropionic acid, 4-guanidinobutyric acid and 2-([amino(imino)methyl]amino)ethane-1-sulfonic acid.
Hybrid compounds that may be mentioned include the salts of the amines mentioned previously with acids such as carbonic acid or hydrochloric acid.
Guanidine carbonate or monoethanolamine hydrochloride may be used in particular.
Preferably, the alkaline agent(s) that are useful in the invention are chosen from aqueous ammonia, alkaline carbonates or bicarbonates, alkanolamines, amino acids in neutral or ionic form, in particular basic amino acids, and preferably corresponding to those of formula (XVIII).
More preferentially, the alkaline agent(s) are chosen from aqueous ammonia, ammonium bicarbonate, ammonium hydroxide, mono-, di- or tri-hydroxy(C1-C6)alkylamines, such as triethanolamine, and mixtures thereof.
Forms of the Composition
The composition(s) comprising the 2-azo(benz)imidazolium dye(s) (a) chosen from the compounds of formula (I), as defined previously, and the fluorescent dye(s) (b) as defined previously, may be in various presentation forms, such as in the form of liquids, lotions, creams or gels or in any other form that is suitable for dyeing keratin fibres.
It may also be packaged under pressure in an aerosol container in the presence of a propellant or in a non-aerosol container and may form a foam.
Additives
When the ingredients used in the dyeing process according to the present invention are present in one or more compositions, said compositions may also optionally comprise one or more additives, different from the ingredients of the invention and among which mention may be made of fatty substances, cationic, anionic, nonionic, amphoteric or zwitterionic surfactants, cationic, anionic, nonionic or amphoteric polymers or mixtures thereof, antidandruff agents, anti-seborrhoea agents, agents for preventing hair loss and/or for promoting hair regrowth, vitamins and provitamins including panthenol, sunscreens, mineral or organic pigments, sequestrants, plasticizers, solubilizers, acidifying agents, mineral or organic thickeners, especially polymeric thickeners, opacifiers or nacreous agents, antioxidants, hydroxy acids, fragrances, preserving agents, pigments and ceramides.
Needless to say, a person skilled in the art will take care to select this or these optional additional compound(s) such that the advantageous properties intrinsically associated with the composition(s) in accordance with the invention are not, or are not substantially, adversely affected by the envisaged addition(s).
The above additives may generally be present in an amount, for each of them, of between 0 and 20% by weight relative to the total weight of the composition comprising them.
The Dyeing Process
The process for dyeing keratin fibres according to the present invention comprises the application to said keratin fibres of the following ingredients:
(a) one or more 2-azo(benz)imidazolium dyes chosen from the compounds of formula (I), as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof, and
(b) one or more fluorescent dyes, as defined previously, it being understood that the 2-azo(benz)imidazolium dye(s) (ingredients (a)) and the fluorescent dye(s) (ingredients (b)) are applied to said keratin fibres together or sequentially.
In other words, the dyeing process according to the present invention may be performed in one or more steps.
According to a particularly preferred embodiment, the 2-azo(benz)imidazolium dye(s) (a) and the fluorescent dye(s) (b), as defined previously, are applied together (or jointly), i.e. simultaneously, to the keratin fibres. According to this embodiment, the dyeing process is performed in one step.
According to this one-step embodiment, the process comprises a step of applying to said keratin fibres a cosmetic composition according to the invention which comprises one or more 2-azo(benz)imidazolium dyes (a) chosen from the compounds of formula (I), as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof, and one or more fluorescent dyes (b) as defined previously.
According to another particularly preferred embodiment, the 2-azo(benz)imidazolium dye(s) (a), as defined previously, and the fluorescent dye(s) (b), as defined previously, are applied sequentially, i.e. successively. According to this other embodiment, the dyeing process is performed in at least two steps.
According to a first embodiment in at least two steps, the fluorescent dye(s) (b), as defined previously, are applied to the keratin fibres subsequently to the 2-azo(benz)imidazolium dye(s) (a), as defined previously. In other words, the fluorescent dye(s) (b), as defined previously, are applied after the 2-azo(benz)imidazolium dye(s) (a), as defined previously.
According to this first embodiment, the process for dyeing keratin fibres comprises at least the following two successive steps:
a first step of applying to said keratin fibres a cosmetic composition comprising one or more 2-azo(benz)imidazolium dyes (a) chosen from the compounds of formula (I), as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof, followed by
a second step of applying to said keratin fibres a cosmetic composition which comprises one or more fluorescent dyes (b), as defined previously.
According to a preferred embodiment in at least two steps, the 2-azo(benz)imidazolium dye(s) (a), as defined previously, are applied to the keratin fibres subsequently to the fluorescent dye(s) (b), as defined previously. In other words, the 2-azo(benz)imidazolium dye(s) (a), as defined previously, are applied after the fluorescent dye(s) (b), as defined previously.
According to this preferred embodiment, the process for dyeing keratin fibres comprises at least the following two successive steps:
a first step of applying to said keratin fibres a cosmetic composition comprising one or more fluorescent dyes (b), as defined previously, followed by
a second step of applying to said keratin fibres a cosmetic composition comprising one or more 2-azo(benz)imidazolium dyes (a) chosen from the compounds of formula (I), as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof.
Preferably, ingredients (a) and (b) are applied to the keratin fibres in a bath ratio that may range from 0.1 to 10 and more particularly from 0.2 to 8. For the purposes of the present invention, the term “bath ratio” means the ratio between the total weight of ingredient (a) or (b) and the total weight of keratin fibres to be treated.
When the dyeing process is performed in one step, ingredients (a) and (b) are advantageously left to stand on the keratin fibres for a time ranging from 1 to 90 minutes and more preferentially for a time ranging from 5 to 60 minutes.
When the dyeing process is performed in at least two steps, each of the ingredients (a) and (b) may be advantageously left to stand on the keratin fibres for a time ranging from 1 to 60 minutes and more preferentially for a time ranging from 5 to 50 minutes.
On conclusion of the dyeing process according to the invention, in one or at least in two steps, the keratin fibres are advantageously rinsed with water. They may optionally be washed with a shampoo, followed by rinsing with water, before being dried or left to dry.
When the dyeing process is performed in at least two steps, the keratin fibres are advantageously rinsed with water between each step. In other words, the dyeing process may comprise an intermediate rinsing step between the application of the first ingredient and the application of the second ingredient. During this intermediate rinsing step, the keratin fibres may optionally be washed with a shampoo, followed by rinsing with water, before being dried or left to dry.
The dyeing process according to the present invention may be performed at room temperature (25° C.) or with heating.
When they are present, the reducing agent(s) may be applied separately or together with one of the ingredients (a) or (b). Preferably, when they are present, the reducing agent(s) are applied together with the ingredient (b).
When they are present, the oxidizing agent(s) may be applied separately or together with one of the ingredients (a) or (b). Preferably, when they are present, the oxidizing agent(s) are applied after the ingredients (a) and (b).
According to a particular embodiment, the process for dyeing keratin fibres according to the present invention comprises the following successive steps:
a first step of applying to said keratin fibres a cosmetic composition comprising one or more 2-azo(benz)imidazolium dyes (a) chosen from the compounds of formula (I), as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof, followed by
a second step of applying to said keratin fibres a cosmetic composition comprising one or more fluorescent dyes (b), as defined previously, and one or more reducing agents, as defined previously.
According to a particular embodiment of the dyeing process of the invention, no step of said process involves an oxidizing agent.
According to another advantageous embodiment of the dyeing process of the invention, no step of said process involves a reducing agent.
The dyeing process according to the present invention may be applied to wet or dry, preferably dry, keratin fibres.
The Multi-Compartment Device
The present invention also relates to a multi-compartment device comprising a first compartment containing one or more 2-azo(benz)imidazolium dyes (a) chosen from the compounds of formula (I) as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof, and a second compartment containing one or more fluorescent dyes (b) as defined previously.
Use
A subject of the present invention is also the use of one or more fluorescent dye(s) (b), as defined previously, combined with one or more 2-azo(benz)imidazolium dye(s) (a) chosen from the compounds of formula (I), as defined previously, and also the optical isomers thereof, the geometrical isomers thereof, the tautomers thereof, the organic or mineral, acid or base salts thereof, the solvates thereof such as hydrates, and mixtures thereof, for the dyeing of light keratin fibres, especially human keratin fibres such as the hair, in chestnut-brown, dark chestnut-brown, brown, brown with a glint or even black, without using an additional dye other than (a) or (b).
According to a particular embodiment, the “keratin fibres” are human keratin fibres and more particularly the hair.
The examples that follow serve to illustrate the invention without, however, being limiting in nature.
In the examples that follow, all the amounts are given as weight percentages relative to the total weight of the composition, unless otherwise indicated.
The synthesis of the 2-azo(benz)imidazolium dyes is known to those skilled in the art. By way of example, the synthesis of the dyes of structure (2a) or (9a) is described in the Ciba Specialty Chemicals Holding Inc. patents WO2004/100912 A2, 2004; The synthesis of compounds (4a), (13a) and (37a) is performed using the methods described, for example, in Russian Journal of Organic Chemistry, 1996, vol. 32, #12, pages 1799-1802; Journal of the Indian Chemical Society, 1968, vol. 45, #5 pages 425-432; L'Oréal CH560539DE2227214, 1972.
Composition (A1), comprising a 2-azo(benzo)imidazolium dye of formula (I) according to the invention, was prepared from the ingredients whose contents are mentioned in the table below.
Composition (B1), comprising a fluorescent dye, was prepared from the ingredients whose contents are mentioned in the table below.
Composition (A1) obtained above was applied to 0.5 g locks of hair containing 90% white hairs, in a bath ratio equal to 2.
After a leave-on time of 30 minutes at room temperature, the locks of hair were rinsed with water, washed with shampoo and dried under a hood for 5 minutes.
Composition (B1), obtained above, was then applied to each of the locks of hair, in a bath ratio equal to 2.
After a leave-on time of 20 minutes at room temperature, the locks of hair were rinsed with water, washed with shampoo and dried under a hood for 5 minutes.
The colour of the locks was evaluated visually.
The results of the colouring on the locks of hair containing 90% white hairs are given in the table below.
The results obtained above show that the sequential application of a 2-azo(benzo)imidazolium dye of formula (I) according to the present invention and of a fluorescent dye makes it possible to obtain very intense and chromatic colours.
These results also show that the process according to the invention, using only two particular direct dyes, a 2-azo(benzo)imidazolium dye of formula (I) combined with a fluorescent dye, makes it possible to obtain dark colours.
Compositions (A1) and (B1) were prepared from the ingredients mentioned in Example 1.
Composition (B1) obtained above was applied to 0.5 g locks of hair containing 90% white hairs, in a bath ratio equal to 2.
After a leave-on time of 20 minutes at room temperature, the locks of hair were rinsed with water, washed with shampoo and dried under a hood for 5 minutes.
Next, composition (A1) obtained above was then applied to each of the locks of hair, in a bath ratio equal to 2.
After a leave-on time of 30 minutes at room temperature, the locks of hair were rinsed with water, washed with shampoo and dried under a hood for 5 minutes.
The colour of the locks was evaluated visually.
The results of the colouring on the locks of hair containing 90% white hairs are given in the table below.
The results obtained above show that the sequential application of a fluorescent dye and of a 2-azo(benzo)imidazolium dye of formula (I) according to the present invention makes it possible to obtain very intense and chromatic colours.
These results also show that the process according to the invention, using only two particular direct dyes, a 2-azo(benzo)imidazolium dye of formula (I) combined with a fluorescent dye, makes it possible to obtain black colours.
Compositions (C1) to (C3) were prepared from the ingredients whose contents are mentioned in the table below.
Each of the compositions (C1) to (C3) obtained above was applied to 0.5 g locks of hair containing 90% white hairs, in a bath ratio equal to 2.
After a leave-on time of 45 minutes at room temperature, the locks of hair were rinsed with water, washed with shampoo and dried under a hood for 5 minutes.
The colour of the locks was evaluated visually.
The results of the colouring on the locks of hair containing 90% white hairs are given in the table below.
The results obtained above show that the process according to the invention makes it possible to obtain very intense and chromatic colours.
These results also show that the combination of only two particular direct dyes, i.e. a 2-azo(benzo)imidazolium dye of formula (I) combined with a fluorescent dye, makes it possible to obtain brown or black colours.
Compositions (A2) and (A3), comprising a 2-azo(benzo)imidazolium dye of formula (I) according to the invention, were prepared from the ingredients whose contents are mentioned in the table below.
Compositions (B2) and (B3), comprising a fluorescent dye, were prepared from the ingredients whose contents are mentioned in the table below.
The compositions (A2), (A3), (B2) and (B3) thus obtained were then applied by means of a brush at an amount of 2 g of composition on 1 g locks.
After a leave-on time of 30 minutes, the locks of hair were wrung dry with a paper and rinsed with water. The locks were then washed with a shampoo (0.4 g of shampoo per 1 g of hair) and left to dry.
The colour of the locks thus obtained was evaluated in the CIE L*a*b* system, using a Minolta Spectrophotometer CM2600D colorimeter.
In this system, L* represents the intensity of the colour, a* indicates the green/red colour axis and b* the blue/yellow colour axis.
The lower the value of L, the darker or more intense the colour. The higher the value of a*, the redder the shade, and the higher the value of b*, the yellower the shade.
The table below represents the colouring intensity values obtained:
Compositions (A2), (A3), (B2) and (B3) obtained above were mixed so as to obtain the following mixtures:
A2+B2 in a 1/1 ratio, and
A3+B3 in a 1/1 ratio.
The compositions (A2+B2) and (A3+B3) thus obtained were then applied by means of a brush at an amount of 2 g of composition on 1 g locks.
After a leave-on time of 30 minutes, the locks of hair were wrung dry with a paper and rinsed with water. The locks were then washed with a shampoo (0.4 g of shampoo per 1 g of hair) and left to dry.
The colour of the locks thus obtained was evaluated in the CIE L*a*b* system, using a Minolta Spectrophotometer CM2600D colorimeter.
In this system, L* represents the intensity of the colour, a* indicates the green/red colour axis and b* the blue/yellow colour axis.
The lower the value of L, the darker or more intense the colour. The higher the value of a*, the redder the shade, and the higher the value of b*, the yellower the shade.
The chromaticity of the colour obtained is measured by (C*) which corresponds to the following equation:
C*=√{square root over ((a*)2+(b*)2)}
The greater the C* value, the more the colour of the locks is chromatic.
The results are given in the table below.
The results obtained above show that the simultaneous application of a 2-azo(benzo)imidazolium dye of formula (I) according to the present invention and of a fluorescent dye, chosen from cyanin, styryl/hemicyanin, and naphthalimide dyes (A2+B2), provides more chromatic colorations than a comparative process, comprising the simultaneous application of a 2-azo(benzo)imidazolium dye and a fluorescent dye different from the fluorescent dyes used in the present invention (A3+B3).
Compositions (A2), (A3), (B2) and (B3) were prepared from the ingredients mentioned in Example 4.
Composition (A2) obtained above was applied by means of a brush at an amount of 2 g of composition on a 1 g lock of hair containing 90% white hairs.
After a leave-on time of 30 minutes, the lock of hair was wrung dry with a paper and rinsed with water.
Next, composition (B2) obtained above was then applied to the lock of hair, by means of a brush at an amount of 2 g of composition per 1 g of lock.
After a leave-on time of 30 minutes, the lock of hair was wrung dry with a paper and rinsed with water. The lock was then washed with a shampoo (0.4 g of shampoo per 1 g of hair) and left to dry.
The same protocol was repeated with compositions (A3) and (B3). In other words, composition (A3) obtained above was applied by means of a brush at an amount of 2 g of composition on a 1 g lock of hair containing 90% white hairs.
After a leave-on time of 30 minutes, the lock of hair was wrung dry with a paper and rinsed with water.
Next, composition (B3) obtained above was then applied to the lock of hair, by means of a brush at an amount of 2 g of composition per 1 g of lock.
After a leave-on time of 30 minutes, the lock of hair was wrung dry with a paper and rinsed with water. The lock was then washed with a shampoo (0.4 g of shampoo per 1 g of hair) and left to dry.
The colour of the locks thus obtained was evaluated in the CIE L*a*b* system, using a Minolta Spectrophotometer CM2600D colorimeter.
In this system, L* represents the intensity of the colour, a* indicates the green/red colour axis and b* the blue/yellow colour axis.
The lower the value of L, the darker or more intense the colour. The higher the value of a*, the redder the shade, and the higher the value of b*, the yellower the shade.
The variation in the colouration of the locks before and after dyeing is measured by (ΔE*) which corresponds to the colour uptake according to the following equation:
ΔE*=(L*−Lo)2+(a*−ao)2+(b*-bo*)2
In this equation, L*, a* and b* represent the values measured after dyeing with (A2, then B2) or (A3, then B3), and L0*, a0* and b0* represent the values measured before dyeing, corresponding to an untreated control lock (100% white hair).
The greater the ΔE* value, the greater the difference in colour of the lock before and after dyeing, which shows good colour uptake.
The results are given in the table below.
The results obtained above show that the sequential application of a 2-azo(benzo)imidazolium dye of formula (I) according to the present invention and of a fluorescent dye, chosen from cyanin, styryl/hemicyanin, and naphthalimide dyes (A2, then B2), results in better dyeing properties, in particular in terms of colour uptake and intensity, than a comparative process (A3, then B3), wherein a fluorescent dye, different from the fluorescent dyes used in the present invention, is applied after a 2-azo(benzo)imidazolium dye.
Compositions (A2), (A3), (B2) and (B3) were prepared from the ingredients mentioned in Example 4.
Composition (B2) obtained above was applied by means of a brush at an amount of 2 g of composition on a 1 g lock of hair containing 90% white hairs.
After a leave-on time of 30 minutes, the lock of hair was wrung dry with a paper and rinsed with water.
Next, composition (A2) obtained above was then applied to the lock of hair, by means of a brush at an amount of 2 g of composition per 1 g of lock.
After a leave-on time of 30 minutes, the lock of hair was wrung dry with a paper and rinsed with water. The lock was then washed with a shampoo (0.4 g of shampoo per 1 g of hair) and left to dry.
The same protocol was repeated with compositions (B3) and (A3). In other words, composition (B3) obtained above was applied by means of a brush at an amount of 2 g of composition on a 1 g lock of hair containing 90% white hairs.
After a leave-on time of 30 minutes, the lock of hair was wrung dry with a paper and rinsed with water.
Next, composition (A3) obtained above was then applied to the lock of hair, by means of a brush at an amount of 2 g of composition per 1 g of lock.
After a leave-on time of 30 minutes, the lock of hair was wrung dry with a paper and rinsed with water. The lock was then washed with a shampoo (0.4 g of shampoo per 1 g of hair) and left to dry.
The colour of the locks thus obtained was evaluated in the CIE L*a*b* system, using a Minolta Spectrophotometer CM2600D colorimeter.
In this system, L* represents the intensity of the colour, a* indicates the green/red colour axis and b* the blue/yellow colour axis.
The lower the value of L, the darker or more intense the colour. The higher the value of a*, the redder the shade, and the higher the value of b*, the yellower the shade.
The variation in the colouration of the locks before and after dyeing is measured by (ΔE*) which corresponds to the colour uptake according to the following equation:
ΔE*=(L*−Lo)2+(a*−ao)2+(b*−bo)2
In this equation, L*, a* and b* represent the values measured after dyeing with (A2, then B2) or (A3, then B3), and L0*, a0* and b0* represent the values measured before dyeing, corresponding to an untreated control lock (100% white hair).
The greater the ΔE* value, the greater the difference in colour of the lock before and after dyeing, which shows good colour uptake.
The chromaticity of the colour obtained is measured by (C*) which corresponds to the following equation:
C*=√{square root over ((a*)2+(b*)2)}
The greater the C* value, the more the colour of the locks is chromatic.
The results are given in the table below.
The results obtained above show that the sequential application of a fluorescent dye, chosen from cyanin, styryl/hemicyanin, and naphthalimide dyes and of a 2-azo(benzo)imidazolium dye of formula (I) according to the present invention (B2, then A2), results in better dyeing properties, in particular in terms of chromaticity, colour uptake and intensity, than a comparative process (B3, then A3), wherein a fluorescent dye, different from the fluorescent dyes used in the present invention, is applied before a 2-azo(benzo)imidazolium dye.
| Number | Date | Country | Kind |
|---|---|---|---|
| 1663242 | Dec 2016 | FR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2017/083879 | 12/20/2017 | WO | 00 |
