WO2014048868A2

WO2014048868A2 - Hair dyeing process using at least one ortho-methoxyphenol, a manganese or zinc salt, hydrogen peroxide and (bi)carbonate

Info

Publication number: WO2014048868A2
Application number: PCT/EP2013/069693
Authority: WO
Inventors: Christophe Rondot; Stéphane SABELLE
Original assignee: L'oreal
Priority date: 2012-09-28
Filing date: 2013-09-23
Publication date: 2014-04-03
Also published as: FR2996124B1; WO2014048868A3; FR2996124A1

Abstract

The present invention relates to a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, in which said fibres are treated with one or more cosmetic compositions containing, taken together or separately in said composition(s), the following ingredients: a) one or more ortho-methoxyphenol(s) of formula (I), b) one or more manganese salt(s) and/or oxide(s) or one or more zinc salt(s) and/or oxide(s), c) hydrogen peroxide or one or more hydrogen peroxide-generating system(s), d) one or more (bi)carbonate(s) or one or more (bi)carbonate- generating system(s), and optionally e) one or more alkalinizing agent(s) different from the bicarbonate(s).

Description

Hair dyeing process using at least one ortho-methoxyphenol, a manganese or zinc salt, hydrogen peroxide and (bi)carbonate

The present invention relates to a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, in which said fibres are treated using one or more cosmetic compositions comprising a) one or more ortho-methoxypheno ls(s) o f specific structure, b) one or more manganese or zinc salt(s) and/or oxide(s), c) hydrogen peroxide or one or more hydrogen peroxide-generating system(s), d) one or more (bi)carbonate(s) or one or more (bi)carbonate-generating system(s), and optionally e) one or more alkalinizing agent(s) different from the (bi)carbonate(s).

It is known practice to obtain "permanent" colourings with dyeing compositions containing oxidation dye precursors, which are generally known as oxidation bases, such as ortho- or para-phenylenediamines, ortho- or para-aminopheno ls and heterocyclic compounds . These oxidation bases are co lourless or weakly coloured compounds which, in combination with oxidizing products, can give rise to coloured compounds by an oxidative condensation process . It is also known that the shades obtained can be varied by combining these oxidation bases with couplers or dyeing modifiers, the latter being chosen in particular from aromatic meta-diamines, meta-aminophenols, meta-dipheno ls and certain heterocyclic compounds, such as indo le compounds. This oxidation dyeing process consists in applying, to the keratin fibres, bases or a mixture o f bases and couplers with hydrogen peroxide (H₂0₂ or aqueous hydrogen peroxide solution), as oxidizing agent, in leaving to diffuse, and in then rinsing the fibres . The colourings resulting therefrom are permanent, strong and resistant to external agents, in particular to light, bad weather, washing, perspiration and rubbing.

However, the commercial hair colourings which they contain generally have the drawback of staining the clothing, of causing odour and comfort problems, and of damaging the keratin fibres . This is particularly the case with oxidation dyes .

In the field of dyeing, it is also known practice to dye keratin substances, such as the hair or the skin, starting from ortho-dipheno l compounds in the presence o f a metal salt, in particular a manganese and/or zinc salt. In particular, documents FR 2 8 14 943 , FR 2 8 14 946, FR 2 8 14 947, FR 2 8 17 469, FR 2 838 053 , FR 2 847 8 10, WO 2009/01 0684, FR 2 939 654, FR 2 939 645 , FR 2 939 648 , FR 2 939 644 and FR 2 939 646 propose compositions for dyeing the skin or keratin fibres, comprising a dye precursor which comprises at least one ortho- diphenol, manganese and/or zinc salts and oxides, alkaline agents of hydrogen carbonate type in a specific manganese and zinc salts and oxides/hydrogen carbonate ratio, and optionally an enzyme . According to said documents, it is possible to obtain colourings on keratin materials with atmospheric oxygen or any oxygen-generating system.

However, the colourings obtained are not strong enough, in particular in the case of hair fibres .

There is thus a need to develop dyeing processes which make it possible to obtain strong colourings starting from specific dye precursors, in particular starting from natural extracts rich in specific dye precursors, while limiting the bleaching o f keratin fibres. In particular, there is a need to obtain colourings that are less aggressive on the hair and simultaneously resistant to external agents (light, bad weather, shampooing) and that are remanent and homogeneous, while at the same time remaining strong and chromatic.

This aim is achieved by the present invention, a subj ect of which is a process for dyeing keratin fibres, in particular human keratin fibres such as the hair, in which said fibres are treated, in one or more steps, with one or more cosmetic compositions containing, taken together or separately in said composition(s), the fo llowing ingredients :

a) one or more ortho-methoxypheno l(s) o f formula (I), as defined below,

b) one or more manganese salt(s) and/or oxide(s)or one or more zinc salt(s) and/or oxide(s),

c) hydrogen peroxide or one or more hydrogen peroxide-generating system(s), d) one or more (bi)carbonate(s) or one or more (bicarbonate- generating system(s),

and optionally e) one or more alkalinizing agent(s) different from the bicarbonate(s) .

According to one particular embodiment of the dyeing process according to the invention, the compound(s) d) and optionally e) are found:

-either in a mixture with the compounds a), b) and c),

- or applied separately after application of a cosmetic composition comprising the compound(s) a), b) and c),

- or applied together with the compound c) after application o f a cosmetic composition comprising the ingredients a) and b),

- or applied together with the compounds a) and c) after application of a cosmetic composition comprising the ingredient b) .

Another subject of the present invention is a cosmetic composition for dyeing keratin fibres, comprising :

a) one or more ortho-methoxypheno l(s) o f formula (I), as defined below,

b) one or more manganese salt(s) and/or oxide(s) or one or more zinc salt(s) and/or oxide(s),

c) hydrogen peroxide or one or more hydrogen peroxide-generating system(s),

d) one or more (bi)carbonate(s) or one or more (bicarbonate- generating system(s),

The dye composition is preferably aqueous .

Another subj ect of the present invention relates to a multicompartment device comprising :

a) one or more ortho-methoxypheno l(s) of formula (I), as defined below,

c) hydrogen peroxide or one or more hydrogen peroxide- generating system(s),

The multicompartment device or "kit" is suitable for implementing the dyeing process according to the invention.

The process according to the invention exhibits the advantage of dyeing human keratin fibres, with powerful, chromatic dyeing results which are resistant to washing operations, to perspiration, to sebum and to light, and which are moreover long-lasting, without detrimental change to said fibres. Furthermore, the colourings obtained using the process give uniform colours from the root to the end of the fibres (little co louring selectivity).

Other subj ects, characteristics, aspects and advantages of the present invention will emerge even more clearly on reading the description and the examples that fo llow. a) ortho-methoxypheno l

In accordance with the present invention, the dyeing process uses one or more ortho-methoxypheno l(s) of formula (I), as defined below.

The ortho-methoxypheno l compound(s) may be present in one or more cosmetic composition used during the dyeing process .

One particular mode of the invention relates to ortho- methoxypheno ls, the phenyl ring of which may be fused to an aromatic or non-aromatic (hetero)cycle.

It is understood that the ortho-methoxypheno ls according to the invention which are used in the composition or the dyeing process of the invention may correspond to a mixture of ortho-methoxypheno ls o f different chemical formulae (I), in particular a mixture of different compounds, but each corresponding to formula (I) and being able to comprise at least one heteroaromatic ring. According to one preferred embodiment of the invention, the dyeing process of the invention or the composition(s) according to the invention use just one compound o f formula (I) .

Furthermore, it should be noted that two adj acent carbon atoms of one o f the (hetero)aromatic rings o f said ortho-methoxypheno ls cannot carry two hydroxyl (OH) groups .

More particularly, the ortho-methoxypheno l(s) o f the invention do not exhibit any (hetero)aromatic rings fused to or placed side-by-side the phenyl group of said ortho-methoxypheno l.

The ortho-methoxypheno ls according to the invention may or may not be salified. They may also be in aglycone form (without attached sugars) or in the form o f glyco sylated compounds.

The ortho-methoxypheno l a) is a compound o f formula (I) below or an enantiomer or diastereoisomer thereof, in salified or non-salified form, optionally in aglycone form:

in which formula (I) the substituents :

· R¹ represents :

- a hydrogen atom,

- a halogen atom,

- a carboxyl radical,

- an alkyl carboxylate or alkoxycarbonyl radical,

- an optionally substituted amino radical,

- an optionally substituted and linear or branched alkyl radical,

- an optionally substituted and linear or branched alkenyl radical,

- an optionally substituted cycloalkyl radical,

- an alkylcarbonyl radical,

- a carboxaldehyde radical, - an alkoxy radical,

- an alkoxyalkyl radical,

- an alkoxyaryl radical, it being possible for the aryl group to be optionally substituted,

- an aryl radical,

- a substituted aryl radical,

- a saturated or unsaturated heterocyclic radical, optionally carrying a cationic or anionic charge, optionally substituted and/or optionally fused with an aromatic ring, preferably a benzene ring, said aromatic ring being optionally substituted, particularly with one or more hydroxyl or glycosyloxy groups,

-a radical comprising one or more silicon atoms,

• R² to R⁴, which may be identical or different, represent:

- a hydrogen atom,

- a halogen atom,

- a hydroxyl radical,

- a carboxyl radical,

- an alkyl carboxylate or alkoxycarbonyl radical,

- an optionally substituted amino radical,

- an optionally substituted and linear or branched alkyl radical,

- an optionally substituted and linear or branched alkenyl radical,

- an optionally substituted cycloalkyl radical,

- an alkylcarbonyl radical,

- a carboxaldehyde radical,

- an alkoxy radical,

- an alkoxyalkyl radical,

- an aryl radical,

- a substituted aryl radical,

-a radical comprising one or more silicon atoms,

it being understood that two hydroxyl radicals cannot be carried by adj acent carbons of the aromatic ring.

In particular, the ortho-methoxypheno ls that can be used in the process of the invention according to a) are of formula (I) in which:

• R¹ represents :

- a hydrogen atom,

- a halogen atom,

- a carboxyl radical,

- an alkyl carboxylate or alkoxycarbonyl radical,

- an optionally substituted and linear or branched alkyl radical,

- an optionally substituted and linear or branched alkenyl radical,

- an optionally substituted cycloalkyl radical,

- an alkylcarbonyl radical,

- a carboxaldehyde radical,

- an alkoxy radical,

• R² to R⁴, which may be identical or different, represent:

- a hydrogen atom,

- a halogen atom,

- a hydroxyl radical,

- a carboxyl radical,

- an alkyl carboxylate or alkoxycarbonyl radical,

- an optionally substituted amino radical,

- an optionally substituted and linear or branched alkyl radical,

- an optionally substituted and linear or branched alkenyl radical,

- an optionally substituted cycloalkyl radical,

- an alkylcarbonyl radical,

- a carboxaldehyde radical,

- an alkoxy radical.

Preferably, the ortho-methoxyphenols according to the invention do not comprise two hydroxyl groups carried by two adjacent carbons . The saturated or unsaturated and optionally fused rings can also be optionally substituted.

The alkyl radicals are linear or branched, saturated hydrocarbon- based radicals, generally of C ₁ -C₂₀ , particularly o f C i -C i o , preferably C i - C₆ alkyl radicals, such as methyl, ethyl, propyl, butyl, pentyl and hexyl.

The alkenyl radicals are unsaturated, linear or branched, C₂-C₂₀ hydrocarbon-based radicals, preferably comprising at least one double bond, such as ethylene, propylene, butylene, pentylene, 2- methylpropylene and decylene.

The aryl radicals are monocyclic or fused or non-fused po lycyclic carbon-based radicals, preferentially comprising from 6 to 30 carbon atoms, at least one ring of which is aromatic; a phenyl, biphenyl, naphthyl, indenyl, anthracenyl and tetrahydronaphthyl are preferentially chosen from the aryl radical; more preferentially, the aryl radicals of the invention are phenyl radicals .

The alkoxy radicals are alkyl-oxy radicals with alkyl as defined previously, preferably C ₁ -C _{1 0} alkyl, such as methoxy, ethoxy, propoxy and butoxy.

The alkoxyalkyl radicals are preferably (C i -C₂o)alkoxy(C i -C₂o)alkyl radicals, such as methoxymethyl, ethoxymethyl, methoxyethyl, ethoxyethyl, etc.

The cycloalkyl radicals are generally C 4 - C 8 cycloalkyl radicals, preferably cyclopentyl and cyclohexyl radicals . The cycloalkyl radicals can be substituted cycloalkyl radicals, in particular substituted with alkyl, alkoxy, carboxylic acid, hydroxyl, amine and ketone groups .

The halogenated radicals are fluorine, chlorine, bromine and iodine atoms.

The alkylcarbonyl radicals are alkylcarbonyl radicals with alkyl as defined previously, preferably C ₁ -C _{1 0} alkyl, such acetyl or propionyl.

The alkoxycarbonyl radicals are -0-C(0)-alkyl radicals as defined previously, such as acetate, propionate, citrate, tartrate, gluconate or lactate. The alkyl, alkenyl, cycloalkyl or heterocyclic radicals, when they are substituted, are substituted with at least one substituent carried by at least one carbon atom, chosen from:

- a halogen atom;

- a hydroxyl group;

- an oxo group;

- a C1-C2 alkoxy radical;

- a C1-C10 alkoxycarbonyl radical;

- a C1-C10 alkylcarbonyl radical;

- a (poly)hydroxy(C2-C4)alkoxy radical;

- an amino radical;

- a quaternary ammonium radical -N R'R"R'", M^" for which R', R" and R'", which may be identical or different, represent a hydrogen atom, or a C1-C4 alkyl group; and M^" represents the counterion of the organic or inorganic acid or of the corresponding halide,

- a 5- or 6-membered heterocycloalkyl radical;

- an optionally cationic 5- or 6-membered heteroaryl radical, preferentially imidazolium, optionally substituted with a (Ci-C4)alkyl radical, preferentially methyl;

- an amino radical substituted with one or two Ci-C₆ alkyl radicals, which may be identical or different, optionally carrying at least:

- one hydroxyl group;

- one amino group optionally substituted with one or two C1-C3 alkyl radicals, said alkyl radicals possibly forming, with the nitrogen atom to which they are attached, a saturated or unsaturated, 5- to 7- membered heterocycle, optionally comprising at least one other nitrogen heteroatom or non-nitrogen heteroatom,

- a quaternary ammonium group -N R'R"R'", M^" for which R', R" and R'", which may be identical or different, represent a hydrogen atom, or a C1-C4 alkyl group; and M^" represents the counterion of the organic or inorganic acid or of the corresponding halide,

or an optionally cationic 5- or 6-membered heteroaryl radical, preferentially imidazolium, optionally substituted with a (Ci-C4)alkyl radical, preferentially methyl; - an acylamino radical (-NR-C(O)-R') in which the radical R is a hydrogen atom, a C₁-C₄ alkyl radical optionally carrying at least one hydroxyl group and the radical R' is a C₁-C₂ alkyl radical; a carbamoyl radical ((R)₂N-C(0)-) in which the radicals R, which may be identical or different, represent a hydrogen atom, a C₁-C₄ alkyl radical optionally carrying at least one hydroxyl group; an alkylsulfonylamino radical (R' S(0)₂-N(R)-) in which the radical R represents a hydrogen atom, a C₁-C₄ alkyl radical optionally carrying at least one hydroxyl group and the radical R' represents a C₁-C₄ alkyl radical or a phenyl radical; an aminosulfonyl radical ((R)₂N-S(0)₂-) in which the radicals R, which may be identical or different, represent a hydrogen atom or a C₁-C₄ alkyl radical optionally carrying at least one hydroxyl group,

- a carboxylic radical in acid form or salified form (preferably salified with an alkali metal or an ammonium, which is optionally substituted);

- a cyano group;

- a nitro group;

- a carboxyl or glycosylcarbonyl group;

- a phenylcarbonyloxy group optionally substituted with one or more hydroxyl groups;

- a glycosyloxy group;

- a phenyl group optionally substituted with one or more non- adjacent hydroxyl groups.

The aryl or heterocyclic radicals or the aryl or heterocyclic part of the radicals, when they are substituted, are substituted with at least one substituent carried by at least one carbon atom, chosen from:

- a C₁-C₁₀ and preferably Ci-Cs alkyl radical optionally substituted with one or more radicals chosen from the following radicals: hydroxyl, Ci-C₂ alkoxy, (poly)hydroxy(C₂-C₄)alkoxy, acylamino, amino substituted with two C₁-C₄ alkyl radicals, which may be identical or different, optionally carrying at least one hydroxyl group, or the two radicals possibly forming, with the nitrogen atom to which they are attached, a saturated or unsaturated, 5- to 7-membered and preferably 5- or 6- membered heterocycle optionally comprising another nitrogen heteroatom or non-nitrogen heteroatom;

- a halogen atom;

- a hydroxyl group;

- a C₁-C₂ alkoxy radical;

- a C₁-C₁₀ alkoxycarbonyl radical;

- a (poly)hydroxy(C₂-C₄)alkoxy radical;

- an amino radical;

- a 5- or 6-membered heterocycloalkyl radical;

- an optionally cationic 5- or 6-membered heteroaryl radical, preferentially imidazolium, optionally substituted with a (Ci-C₄)alkyl radical, preferentially methyl;

- one hydroxyl group;

- one amino group optionally substituted with one or two C₁-C3 alkyl radicals, said alkyl radicals possibly forming, with the nitrogen atom to which they are attached, a saturated or unsaturated, 5- to 7- membered heterocycle, optionally comprising at least one other nitrogen heteroatom or non-nitrogen heteroatom,

- a quaternary ammonium group -N R'R"R'", M^" for which R', R" and R'", which may be identical or different, represent a hydrogen atom, or a C₁-C₄ alkyl group; and M^" represents the counterion of the organic or inorganic acid or of the corresponding halide,

or an optionally cationic 5- or 6-membered heteroaryl radical, preferentially imidazolium, optionally substituted with a (Ci-C₄)alkyl radical, preferentially methyl;

- an acylamino radical (-N(R)-C(0)R') in which the radical R is a hydrogen atom or a C₁-C₄ alkyl radical optionally carrying at least one hydroxyl group and the radical R' is a C₁-C₂ alkyl radical;

- a carbamoyl radical ((R)₂N-C(0)-) in which the radicals R, which may be identical or different, represent a hydrogen atom, a C₁-C₄ alkyl radical optionally carrying at least one hydroxyl group; an alkylsulfonylamino radical (R' S(0)₂-N(R)-) in which the radical R represents a hydrogen atom or a C ₁ -C₄ alkyl radical optionally carrying at least one hydroxyl group, and the radical R' represents a C ₁ -C₄ alkyl radical, or a phenyl radical;

- an amino sulfonyl radical ((R)₂N- S(0)₂-) in which the radicals R, which may be identical or different, represent a hydrogen atom or a C i -

C₄ alkyl radical optionally carrying at least one hydroxyl group;

- a cyano group;

- a nitro group;

- a polyhaloalkyl group, preferentially trifluoromethyl;

- a carboxyl or glyco sylcarbonyl group;

- a glycosyloxy group;

- a phenyl group optionally substituted with one or more non- adj acent hydroxyl groups and/or alkoxy groups.

The term "optionally substituted amino " radical is understood to mean an amino group which can carry one or two :

- C i -C₆ alkyl radicals, which may be identical or different, optionally carrying at least:

i) a hydroxyl group,

ii) an amino group optionally substituted with one or two C ₁ - C3 alkyl radicals, said alkyl radicals or else the two alkyl radicals forming, with the nitrogen atom to which they are attached, a saturated or unsaturated, optionally substituted 5 - to 7-membered heterocycle, optionally comprising at least one other nitrogen heteroatom or non- nitrogen heteroatom,

- radicals -C(0)(alkyl), it being possible for the alkyl group to be optionally substituted,

- radicals -C(0)0(alkyl), it being possible for the alkyl group to be optionally substituted, - radicals -C(0)NH(alkyl), it being possible for the alkyl group to be optionally substituted,

- radicals -S0₂(alkyl), it being possible for the alkyl group to be optionally substituted. The term " glycosyl radical" is understood to mean a radical resulting from a monosaccharide or polysaccharide.

The radicals comprising one or more silicon atoms are preferably polydimethylsiloxane, polydiphenylsiloxane, polydimethylphenylsiloxane or stearoxy dimethicone radicals.

The heterocyclic radicals are generally radicals comprising, in at least one ring, one or more heteroatoms chosen from O, N and S , preferably O or N, optionally substituted with in particular one or more alkyl, alkoxy, carboxylic acid, hydroxyl, amine or ketone groups. These rings can comprise one or more oxo groups on the carbon atoms o f the heterocycle.

Mention may be made, among the heterocyclic radicals which can be used, of the furyl, pyranyl, pyrrolyl, imidazolyl, pyrazolyl, pyridyl or thienyl groups .

More preferably, the heterocyclic groups are fused groups, such as benzo furanyl, chromenyl, xanthenyl, indo lyl, isoindo lyl, quino lyl, isoquino lyl, chromanyl, isochromanyl, indolinyl, isoindolinyl, coumarinyl or isocoumarinyl groups, it being possible for these groups to be substituted, in particular with one or more non-adj acent hydroxyl groups .

More particularly, the ortho-methoxyphenol(s) of the invention is (are) of formula (la) below or an enantiomer or diastereoisomer thereof, in salified or non-salified form, optionally in aglycone form:

in which formula (la) :

• R¹ represents :

an alkoxy radical, preferably C i -C₆ alkoxy radical, such as methoxy,

a linear or branched, optionally substituted alkyl radical, preferably substituted with a hydroxyl or

a hydrogen atom,

• R² represents

an alkoxy radical, preferably C i -C₆ alkoxy radical, such as methoxy,

a linear or branched, preferably C i -C₆ , alkyl radical, such as methyl, or

a hydrogen atom;

· R³ represents

a) a hydrogen atom,

b) a hydroxyl group,

c) a linear or branched (C i -C₆) alkyl radical, optionally substituted with one or more hydroxyl groups, preferably a hydroxyl group, or

d) an alkenyl group chosen from:

i) R₅-C(0)-(CH=CH)_n-(*) with

R₅ representing a hydrogen atom or an alkyl group, preferably C i -C₆ alkyl group, such as methyl,

n representing an integer inclusively between 1 and 4, preferably n = 1 and

• denoting the point of attachment of said group to the rest of the mo lecule;

ii) R₅-0-(ALK)_p-(CH=CH)_n-(*) with

R₅ , n and * being as defined previously, ALK representing a linear or branched, divalent (C i -C₆), preferably (C ₁ -C₂), alkylene radical, such as methylene, and

p = 0 or 1 , preferably 1 ; and

iii) the arylalkenyl(alkyl) group of formula below :

in which formula (iii) :

* is as defined previously,

R₆ and R₇, which may be identical or different, representing a hydrogen atom or a carboxyl group,

Rs representing an alkyl group, preferably C i -C₆ alkyl group, such as methyl,

p representing an integer inclusively between 0 and 4, preferably p is 0 or 2,

representing a single bond or a double bond,

q, which may be identical or different, being 0 or 1 , preferably q= l ,

ALK, which may be identical or different, representing a linear or branched, divalent (C i -C₆), preferably (C 1 -C2), alkylene group, such as methylene. More particularly, the compound of formula (la) comprises an R³ alkenyl group iii) as defined previously with p being 2, and in which one of the two groups R₆ or R₇ represents a carboxyl group and the other radical R₆ or R₇ respectively represents a hydrogen atom. More preferentially, the compound of formula (la) has an axis o f symmetry C2.

According to another preferred embodiment of the invention, the ortho-methoxypheno l(s) o f the invention is (are) of formula (lb) or an enantiomer or diastereoisomer thereof, in salified or non-salified form, optionally in aglycone form:

in which formula (lb):

• R² represents

a hydrogen atom or

an alkoxy radical, preferably Ci-C₆ alkoxy radical, such as methoxy or

a linear or branched, preferably Ci-C₆, alkyl radical, such as methyl,

• R⁴ represents

a hydroxyl radical or

an alkoxy radical, preferably Ci-C₆ alkoxy radical, such as methoxy.

Preferentially, the ortho-methoxyphenols of formula (I) are chosen from compounds 1 to 19.

-but-2-ene- l ,4-diylbis(2-methoxyphenol)

Even more preferentially, the ortho-methoxypheno ls correspond to compounds 2 and 3.

The salts of the ortho-methoxypheno ls o f the invention can be salts of acids or of bases. The acids can be inorganic or organic. Preferably, the acid is hydrochloric acid, which results in chlorides . The bases can be inorganic or organic. In particular, the bases are alkali metal hydroxides, such as sodium hydroxide, which results in sodium salts.

The ortho-methoxypheno ls that are of use in the process of the invention can be natural or synthetic. Included among the natural ortho- methoxypheno ls are compounds that may be present in nature and that are reproduced by chemical (semi)synthesis.

According to one particular embodiment of the invention, the composition comprises, as ingredient a), one or more synthetic ortho- methoxypheno ls) of formula (I) that do not exist in nature.

According to another preferred embodiment of the invention, the composition that is o f use in the process for dyeing keratin fibres comprises, as ingredient a), one or more natural ortho-methoxypheno l(s) of formula (I) .

When the dye precursors exhibit D and L forms, both forms can be used in the compositions according to the invention, as can the racemates. According to one embodiment, the natural ortho-methoxypheno l(s) of formula (I) is (are) chosen from extracts of animals, of bacteria, of fungi, o f algae, of plants and of fruits, used in their entirety or partially. In particular regarding the plants, the extracts are derived from fruits, including citrus fruits, from vegetables, from trees and from shrubs. Mixtures of these extracts that are rich in ortho-methoxypheno ls as defined previously may also be used.

Preferably, the natural ortho-methoxypheno l(s) o f the invention is (are) derived from extracts of plants or of plant parts .

For the purposes of the invention, these extracts will be put into the same category as compounds a) . The extracts are obtained by extraction of various plant parts, such as, for example, the root, the wood, the bark, the leaf, the flower, the fruit, the seed, the pod or the peel.

Use may also be made o f mixtures of plant extracts.

Preferably, these extracts do not contain ortho-dipheno ls.

According to one particular embodiment of the invention, the ortho- methoxypheno l(s) of formula (I) is (are) a natural extract or natural extracts, rich in ortho-methoxypheno ls. According to one preferred mode, the ortho-methoxypheno l(s) o f formula (I) is (are) solely a natural extract or natural extracts .

The natural extracts according to the invention can be provided in the form o f powders or liquids . Preferably, the extracts of the invention are in the form o f powders.

According to the invention, the synthetic ortho-methoxypheno l(s), the natural ortho-methoxypheno ls(s) and/or the natural extract(s) used as ingredient a) in one or more composition(s) that are of use in the process according to the invention preferably represent(s) from 0.001 % to 20% by weight o f the total weight of the composition(s) comprising the ortho- methoxypheno ls) or the extract(s) .

As regards the pure ortho-methoxypheno ls, the content in the composition(s) comprising them is preferably between 0.001 %) and 5 % by weight of each o f these compositions . As regards the extracts, the content in the composition(s) comprising the extracts per se is preferably between 0.5 % and 20%> by weight of each o f these compositions . b) manganese or zinc salt and/or oxide

The dyeing process according to the invention uses one or more manganese (Mn) salt(s) and/or oxide(s) or one or more zinc (Zn) salt(s) and/or oxide(s) . The manganese or zinc salt(s) and/or oxide(s) may be used in one or more cosmetic composition(s) used during the dyeing process.

For the purposes of the present invention, the term " salts" means the actual salts derived in particular from the action o f an acid on a metal.

Among the salts, mention may be made o f halides, such as chlorides, fluorides and iodides; sulfates, phosphates; nitrates; carboxylic acid salts and po lymer salts, and also mixtures thereof.

More particularly, the manganese salt is different from manganese carbonate, manganese hydrogen carbonate or manganese dihydrogen carbonate.

The carboxylic acid salts that may be used in the invention also include salts of hydroxylated carboxylic acids such as gluconate.

As examples of polymer salts, mention may be made o f manganese polyvinylpyrrolidonecarboxylate.

As examp les, mention may be made o f halides, sulfates, phosphates, nitrates and perchlorates, carboxylic acid salts, such as gluconates, and also mixtures thereo f. More preferentially, mention may be made of manganese chloride, manganese fluoride, manganese acetate tetrahydrate, manganese lactate trihydrate, manganese phosphate, manganese iodide, manganese nitrate trihydrate, manganese bromide, manganese perchlorate tetrahydrate, manganese sulfate monohydrate and manganese gluconate. The salts advantageously used are manganese gluconate and manganese chloride.

Among the zinc salts, mention may be made of zinc sulfate, zinc gluconate, zinc chloride, zinc lactate, zinc acetate, zinc glycinate and zinc aspartate.

The manganese and zinc salts and/or oxides may be introduced in so lid form into the compositions or may be derived from a natural, mineral or thermal water that is rich in these ions or alternatively from seawater (in particular the Dead Sea) . They may also originate from mineral compounds, for instance earths, ochres such as clays (for example green clay), or even from a plant extract containing them (cf. for example Patent FR 2 8 14 943) .

According to one preferred embodiment of the invention, the manganese or zinc salt(s) and/or oxide(s) used represent(s) from 0.00 1 % to 0. 1 % by weight, approximately, of the total weight of the composition(s) containing said metal salt(s) and/or oxide(s), and even more preferentially from 0.05 % to 10% by weight approximately.

In particular, the metal salts nd/or oxides of the invention are in oxidation state II, such as Mn(II) and Zn(II) .

Preferably, the dyeing process of the invention uses one or more manganese salt(s), in particular Mn(II) metal salts.

Even more preferentially, the manganese salt(s) is (are) chosen from carboxylic acid salts o f manganese, in particular manganese gluconate, and manganese halides, such as manganese chloride, and more particularly manganese gluconate. c) hydrogen peroxide or hydrogen peroxide-generating system In the context of the present invention, the third constituent is hydrogen peroxide or a hydrogen peroxide-generating system, such as : a) urea peroxide;

b) polymeric complexes that can release hydrogen peroxide, such as po lyvinylpyrrolidone/H202 in particular in the form o f powders, and the other polymeric complexes described in US 5 008 093 ; US 3 376 1 10; US 5 1 83 901 ;

c) oxidases that produce hydrogen peroxide in the presence of a suitable substrate (for example glucose in the case of glucose oxidase or uric acid with uricase);

d) metal peroxides that generate hydrogen peroxide in water, for instance calcium peroxide or magnesium peroxide;

e) perborates; or

f) percarbonates .

According to one preferred embodiment of the invention, the composition comprises one or more hydrogen peroxide-generating system(s) chosen from:

a) urea peroxide;

b) polymeric complexes that can release hydrogen peroxide, chosen from po lyvinylpyrro lidone/H₂02 ;

c) oxidases;

e) perborates and

f) percarbonates.

In particular, the third constituent is hydrogen peroxide or urea peroxide.

Moreover, the composition(s) comprising hydrogen peroxide or the hydrogen peroxide generator may also contain various adjuvants conventionally used in hair dyeing compositions and as defined hereinbelow.

According to one particular mode of the invention, the hydrogen peroxide used or the hydrogen peroxide-generating system(s) used preferably represent(s) from 0.001 % to 12% by weight of hydrogen peroxide relative to the total weight of the composition(s) containing it/them, and even more preferentially from 0.2% to 2.7% by weight. d) (bi)carbonate(s) or (bi)carbonate-generating system

In accordance with the present invention, the dyeing process uses one or more (bi)carbonate(s) or one or more (bi)carbonate-generating system(s).

The (bi)carbonate(s) or the (bi)carbonate-generating system(s) may be used in one or more cosmetic compositions during the dyeing process .

The term " (bi)carbonate-generating system" is understood to mean a system which generates (bi)carbonate in situ, for instance carbon dioxide in water or by buffering carbonate with an inorganic or organic acid.

The (bi)carbonate(s) is (are) chosen from: a) carbonates of alkali metals ((Met⁺)₂, C0₃ ^2~), of alkaline-earth metals (Met'²⁺, C0₃ ^2~), of ammonium ((R"₄N⁺)₂,C0₃ ^2~) Or of phosphonium (R"₄P⁺)₂,C0₃ ^2~ with Met' representing an alkaline-earth metal and Met representing an alkali metal, and R", which may be identical or different, representing a hydrogen atom, or an optionally substituted (Ci-C₆)alkyl group such as hydroxyethyl,

b) bicarbonates, also known as hydrogen carbonates, of following formulae:

R' ⁺ , HC0₃ ^" with R' representing a hydrogen atom, an alkali metal, an ammonium group R"₄N - or a phosphonium group R"₄P - where R", which may be identical or different, represent a hydrogen atom, or an optionally substituted (Ci-C₆)alkyl group such as hydroxyethyl and, when R' represents a hydrogen atom, the hydrogen carbonate is then known as a dihydrogen carbonate (C0₂.H₂0); and

Met'²⁺ (HC0₃ ^")₂ with Met' representing an alkaline-earth metal.

More particularly, the (bi)carbonate(s) is (are) chosen from alkali metal, alkaline-earth metal or ammonium (bi)carbonates; preferentially, alkali metal or ammonium (bi)carbonates.

Mention may be made of Na, K, Mg and Ca carbonates or hydrogen carbonates and mixtures thereof, in particular of sodium hydrogen carbonate. These hydrogen carbonates can originate from a natural water, for example spring water from the Vichy basin or from La Roche-Posay or Badoit water (cf. patent, for example the document FR 2 814 943). In particular, mention may be made of sodium carbonate [497-19-8] = Na₂C0₃, sodium hydrogen carbonate or sodium bicarbonate [144-55-8] = NaHC0₃, and sodium dihydrogen carbonate = Na(HC0₃)₂.

According to the invention, the (bi)carbonate agent(s) used preferably represent(s) from 0.001% to 10% by weight of the total weight of the composition(s) containing the (bi)carbonate agent(s) and even more preferentially from 0.005% to 5% by weight.

Preferably, the (bi)carbonate used in the dyeing process of the composition is ammonium (bi)carbonate or sodium (bi)carbonate. e) alkalinizing agent(s) different from the bicarbonate(s)

The alkalinizing agent which can be used in the dyeing process according to the invention as fifth ingredient is different from the (bi)carbonate(s) d) as defined previously. It is an agent which makes it possible to increase the pH of the composition(s) in which it is present. The alkalinizing agent is a Bronsted, Lowry or Lewis base. It can be inorganic or organic.

In particular, said agent is chosen from i) aqueous ammonia, ii) alkano lamines such as monoethanolamine, diethanolamine, triethanolamine and derivatives thereof, iii) oxyethylenated and/or oxypropylenated ethylenediamines, iv) inorganic or organic hydroxides, v) alkali metal silicates such as sodium metasilicates, vi), amino acids, preferably basic amino acids such as arginine, lysine, ornithine, citrulline and histidine, and vii) the compounds o f formula (II) below:

N W N

/ \

^Rc ^Rd (ii)

in which:

- W is a divalent (C i - C s)alkylene group, preferably a propylene group , which is optionally substituted in particular with a hydroxyl group or a C 1 - C4 alkyl radical;

- R_a, R_b, R_c and R_d, which may be identical or different, represent a hydrogen atom or a C 1 - C4 alkyl or C 1 - C4 hydroxyalkyl radical.

The inorganic or organic hydroxides are preferably chosen from i) hydroxides o f an alkali metal, ii) hydroxides o f an alkaline-earth metal, for instance sodium hydroxide or potassium hydroxide, iii) hydroxides of a transition metal, such as hydroxides of metals from groups III, IV, V and VI, iv) hydroxides o f lanthanides or of actinides, quaternary ammonium hydroxides and guanidinium hydroxide.

Preferentially, whether for the composition according to the invention or the process imp lemented in the invention, the alkalinizing agent is not sodium hydroxide NaOH. More generally and preferentially, whether for the composition according to the invention or the process implemented in the invention, the alkalinizing agent is not an alkali metal hydroxide XOH, with X = alkali metal.

The hydroxide can be formed in situ, such as, for example, guanidine hydroxide, by reaction o f calcium hydroxide and guanidine carbonate.

The alkalinizing agent(s) d) as defined previously can preferably represent from 0.001 % to 10% by weight of the weight of the composition(s) containing them, more particularly from 0.005 % to 8% by weight of the composition.

Preferably, the alkaline agent(s) is (are) chosen from alkano lamines, in particular monoethano lamine.

- water:

According to one embodiment of the invention, water is preferably included in the process o f the invention. It may originate from the moistening of the keratin fibres and/or from the composition(s) comprising compounds a) to d) and optionally e), as defined previously, or from one or more other compositions .

Preferably, the water originates at least from a composition comprising at least one compound chosen from a) to d) and optionally e), as defined previously.

- cosmetic compositions : The cosmetic compositions according to the invention are cosmetically acceptable, i. e. they comprise a dyeing support that generally contains water or a mixture of water and of one or more organic so lvents or a mixture of organic solvents .

The term "organic solvent" is understood to mean an organic substance which is capable of dissolving or dispersing another substance without chemically mo difying it.

- organic so lvents : Examples o f organic so lvents that may be mentioned include C 1 - C 4 lower alkanols, such as ethanol and isopropanol; polyo ls and polyol ethers such as 2-butoxyethano l, propylene glycol, propylene glycol monomethyl ether, diethylene glyco l monoethyl ether and monomethyl ether, hexylene glycol, and also aromatic alcoho ls, for instance benzyl alcoho l or phenoxyethano l.

The organic so lvents are present in proportions preferably o f between 1 % and 40% by weight approximately, relative to the total weight of the dye composition and even more preferably between 5 % and 30% by weight approximately.

- adjuvants :

The composition(s) that is (are) o f use in the dyeing process in accordance with the invention can also contain various adjuvants conventionally used in hair dyeing compositions, such as anionic, cationic, non-ionic, amphoteric or zwitterionic surfactants or mixtures thereo f, anionic, cationic, non-ionic, amphoteric or zwitterionic polymers or mixtures thereo f, inorganic or organic thickening agents, in particular anionic, cationic, non-ionic and amphoteric po lymeric associative thickeners, antioxidants, penetrating agents, sequestering agents, fragrances, buffers, dispersing agents, conditioning agents, such as, for example, vo latile or non-vo latile and modified or unmodified silicones, film-forming agents, ceramides, preservatives and opacifying agents .

Said adjuvants are preferably chosen from surfactants, such as anionic or non-ionic surfactants or mixtures thereo f, and inorganic or organic thickening agents .

The above adjuvants are generally present in an amount for each of them o f between 0.01 % and 40% by weight, relative to the weight of the composition, and preferably between 0. 1 % and 20%> by weight, relative to the weight of the composition.

Needless to say, those 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) that are of use in the dyeing process in accordance with the invention are not, or are not substantially, adversely affected by the envisaged addition(s).

- additional dyes :

The dyeing process using the ingredients a) to d) and optionally e), as previously defined, may also use one or more additional direct dyes . These direct dyes are chosen, for example, from those conventionally used in direct dyeing, and among which mention may be made of any commonly used aromatic and/or non-aromatic dye such as neutral, acidic or cationic nitrobenzene direct dyes, neutral, acidic or cationic azo direct dyes, natural direct dyes such as ort/zo-diphenols, neutral, acidic or cationic quinone and in particular anthraquinone direct dyes, azine, triarylmethane, indoamine, methine, styryl, porphyrin, metalloporphyrin, phthalocyanine and methine cyanine direct dyes, and fluorescent dyes.

Mention may be made, among natural direct dyes, of lawsone, juglone, indigo, isatin, curcumin, spinulosin, apigenidin and orceins . Use may also be made o f extracts or decoctions comprising these natural dyes and in particular henna-based poultices or extracts.

According to the invention, the direct dye(s) used in the composition according to the invention which comprises the ingredients a) to d) and optionally e), as previously defined, or the composition(s) of the dyeing process according to the invention, preferably represent from 0.001 % to 10% by weight approximately of the total weight of the composition(s) and even more preferentially from 0.05 % to 5 % by weight approximately.

The composition according to the invention or the composition(s) of the process using the ingredients a) to e) as previously defined may also comprise one or more oxidation bases and/or one or more couplers conventionally used for dyeing keratin fibres.

Mention may be made, among the oxidation bases, of para- phenylene diamines, bis(phenyl)alkylenediamines, para-aminophenols, bis-para-aminophenols, ortho-aminophenols, heterocyclic bases and addition salts thereo f. Mention may in particular be made, among these couplers, of meta- phenylenediamines, meta-aminophenols, meta-dipheno ls, naphthalene couplers, heterocyclic couplers and addition salts thereo f.

The oxidation base(s) present in said composition(s) that is (are) used in the process is (are) generally each present in an amount of between 0.001 % and 10% by weight of the total weight of the composition(s) containing it or them.

The cosmetic composition(s) of the invention can be provided in various formulation forms, such as a powder, a lotion, a foam, a cream or a gel, or in any other form appropriate for dyeing keratin fibres. They can also be packaged in a propellant-free pump-action spray or under pressure in an aerosol container in the presence of a propellant and can form a foam.

- pH of the composition(s) :

According to one embodiment, the pH of the cosmetic composition(s) containing d) one or more (bi)carbonate(s) or one or more (bi)carbonate-generating system(s) is alkaline, i. e. greater than 7, preferably between 8 and 12, and more particularly between 8 and 10.

According to one particular embodiment of the invention, the pH o f the cosmetic composition comprising d) one or more (bi)carbonate(s) or one or more (bi)carbonate-generating system(s) and optionally e) one or more alkalinizing agent(s) different from the (bi)carbonate(s) is alkaline, i.e . greater than 7, preferably between 8 and 12.

According to one embodiment, if one or more cosmetic composition(s) used during the dyeing process do(es) not contain (bi)carbonates, the pH o f the composition(s) containing hydrogen peroxide or a hydrogen peroxide-generating system is preferably less than 7 , more particularly between 1 and 5.

In particular, the cosmetic composition consisting so lely o f hydrogen peroxide has a pH of less than 7. The H o f these compositions may be adjusted to the desired value by means o f alkalinizing or acidifying agents normally used in the dyeing o f keratin fibres, or alternatively using standard buffer systems.

Among the acidifying agents for the compositions used in the invention, examples that may be mentioned include inorganic or organic acids, for instance hydrochloric acid, orthophosphoric acid, sulfuric acid, carboxylic acids, for instance acetic acid, tartaric acid, citric acid or lactic acid, or sulfonic acids.

Among the alkalinizing agents concerned are the agents as defined previously under the heading "e) alkalinizing agent(s)" .

-dyeing process in one or more steps

According to one embodiment, the process for dyeing keratin fibres is performed in a single step by applying to the keratin fibres an aqueous dye composition comprising :

a) one or more ortho-methoxypheno l(s) o f formula (I), as defined above,

c) hydrogen peroxide or one or more hydrogen peroxide-generating system(s),

and optionally e) one or more alkalinizing agent(s) different from the (bi)carbonate(s) .

The leave-on time after application is generally set at between 3 and

120 minutes, preferentially between 10 and 60 minutes and more preferentially between 15 and 45 minutes .

According to another embodiment, the process for dyeing keratin fibres is performed in two or three steps .

According to one particular mode of the invention, the process for dyeing keratin fibres is performed in a single step by applying to the keratin fibres an aqueous dye composition comprising the ingredients a), b), c), d) and optionally e), as defined previously. The leave-on time after application is generally set at between 3 and 120 minutes, preferentially between 10 and 60 minutes and more preferentially between 15 and 45 minutes .

According to another particular mode of the invention, the process for dyeing keratin fibres is performed in two steps .

In a first variant of this process in two steps, the first step consists in applying to said fibres a composition comprising the ingredients a), b) and c), as defined previously, and then, in a second step, a composition comprising the ingredients d) and optionally e), as defined previously, is applied to said fibres. Preferably, according to this first variant, at least one of the two compositions is aqueous. According to one preferred embodiment, the composition comprising the ingredients a), b) and c) is aqueous. According to another embodiment of the invention, the composition comprising the ingredients d) and optionally e) is an aqueous composition. Preferentially, the two compositions are aqueous . These aqueous compositions may also comprise one or more fatty substances, such as liquid petroleum j elly.

In a second variant of the process for dyeing keratin fibres in two steps, the first step consists in applying to said fibres a composition comprising the ingredients a) and b), as defined previously, and then, in a second step, a second composition comprising the ingredients c), d) and optionally e), as defined previously, is applied to said fibres.

In a third variant of the process for dyeing keratin fibres in two steps, the first step consists in applying to said fibres a composition comprising the ingredient b), as defined previously, and then, in a second step, a composition comprising the ingredients a), c), d) and optionally e), as defined previously, is applied to said fibres .

According to one particular dyeing process of the invention, said process is performed in at least two steps ending with the treatment of the keratin fibres with the ingredient d) and optionally e), and may be fo llowed by post-treatment steps such as shampooing with a standard shampoo, rinsing, for example with water, and/or drying the keratin fibres by heat treatment as defined hereinafter; it being understood that said process does not involve intermediate rinsing just before the step that uses the ingredient d) .

Preferentially, the process according to the invention in at least two steps does not invo lve intermediate rinsing between the first and the second step, i. e. between the application of the mixture of the ingredients a), b), c) and d) or between the application o f mixture a), b) and of mixture c), d).

According to one particularly advantageous process, the keratin fibres are, just before the step which uses the ingredient d) :

a) either wiped mechanically as described hereinafter,

b) or dried by heat with a heat treatment as described hereinafter, c) or not rinsed, i. e. the steps are performed successively.

Preferably, between the first and the second step of the dyeing process of the invention, the fibres are :

a) either wiped mechanically as described hereinafter,

b) or dried by heat with a heat treatment as described hereinafter, c) or not rinsed, i. e. steps 1 and 2 are performed successively.

More preferentially, between the first and second step, the keratin fibres are wiped, preferentially using a towel or absorbent paper, or are dried by heat with a heat treatment at a temperature particularly between

60 and 220°C and preferably between 120 and 200°C .

According to another particular mode of the invention, between the application o f the mixture of the ingredients a), b), c) and d) or between the application o f mixture a), b) and mixture c), d), the locks are rinsed very rapidly, between 1 second and 1 minute, more particularly between

1 second and 30 seconds and preferentially between 2 and 5 seconds, such as 2 seconds, under tap water or with an intense-j et showerhead.

This rapid rinsing step is followed by mechanical wiping as described hereinafter.

For the latter three processes, the leave-on time after application for the first step is generally set at between 3 and 120 minutes, preferentially between 10 and 60 minutes and more preferentially between 15 and 45 minutes. The application time for the second step is generally set at between 3 and 120 minutes, preferentially between 3 and 60 minutes and more preferentially between 5 and 45 minutes .

Whatever the mode o f application, the application temperature is generally between ambient temperature ( 15 °C to 25 °C) and 80°C and more particularly between 15 °C and 45 °C . Thus, after application o f the composition according to the invention, the head of hair can advantageously be subj ected to a heat treatment by heating to a temperature of between 30° C and 60°C . In practice, this operation can be carried out using a styling hood, a hairdryer, an infrared ray dispenser and other conventional heating appliances . Use may be made, both as means for heating and for smoothing the head o f hair, o f a heating iron at a temperature of between 60°C and 220°C and preferably between 120°C and 200°C .

Whatever the mode o f application, wiping and/or drying of the keratin fibres can optionally be performed between each step, in particular before carrying out the step comprising the application o f a composition containing the ingredient d) .

One particular mode of the invention relates to a dyeing process which is carried out at ambient temperature (25 °C) .

In all the particular modes and variants of the processes previously described, the compositions mentioned are or can be ready-for-use compositions that may result from the extemporaneous mixing of two or more compositions and in particular of compositions present in dyeing kits .

- dyeing device or kit

Another subj ect of the invention is a multicompartment dyeing device or kit. Advantageously, this kit comprises from 2 to 4, or even 5 , compartments containing from 2 to 4, or even 5 , compositions, in which are distributed the fo llowing ingredients :

a) one or more ortho-methoxypheno l(s) of formula (I), as defined above, b) one or more manganese salt(s) and/or oxide(s) or one or more zinc salt(s) and/or oxide(s),

c) hydrogen peroxide or one or more hydrogen peroxide-generating system(s),

and optionally e) one or more alkalinizing agent(s) different from the (bi)carbonate(s),

said compositions being aqueous or pulverulent, particularly at least one of these compositions being aqueous .

The compositions of the device according to the invention are packaged in separate compartments, optionally accompanied by suitable application means which are identical or different, such as fine brushes, coarse brushes or sponges .

The device mentioned above may also be equipped with a means for dispensing the desired mixture on the hair, for instance the devices described in patent FR 2 586 913.

The examples that follow serve to illustrate the invention without, however, being limiting in nature.

Examples o f dyeing

In the fo llowing example, the colouring uptake ΔΕ * was evaluated on the basis o f the co lour of the dyed hair and of the initial co lour of the undyed hair.

1 . Compositions tested

(*) 0. 144 g of 167-vo lume aqueous hydrogen peroxide solution The ortho-methoxypheno ls used have the following structures :

Composition B (developer) Amount

Sodium bicarbonate d) 2.6 g

Monoethanolamine e) 2 g

Demineralized water qs 100 g 2. Procedure

The composition A is applied to locks of natural hair comprising 90% white hairs that has been permanent-waved, in a proportion of 12 grams of composition per gram of hair.

The composition is then left on the locks for 30 minutes at a temperature of 50°C under aluminium foil.

After this, the impregnated hair is wiped using an absorbent paper towel to remove the excess composition.

The composition B is then applied to each of the locks in a proportion of 4 grams of composition per gram of lock. The composition B has a pH = 9.5. The leave-on time is 10 minutes at ambient temperature.

The hair is then rinsed with water, washed with a standard shampoo and dried under a hood.

3. Colorimetric results

The colouring uptake ΔΕ* is measured. The colour of the locks was evaluated in the CIE L* a* b* system, using a Minolta Spectrophotometer CM2600D colorimeter. In this L* a* b* system, the three parameters denote, respectively, the colour intensity (L*), the green/red colour axis (a*) and the blue/yellow colour axis (b*).

The variation in colouring between the locks of permanent-waved white hair comprising 90% of white hairs (90 WP) that are untreated (L₀* a₀* bo*) and after dyeing (L* a* b*) is defined by (ΔΕ*) according to the following equation:

AE* = -/( *- ₀*)²+(a*-a₀*)² +(b*-b₀*)²

In this equation, L*, a* and b* represent the values measured on locks of hair after dyeing and L₀*, a₀* and bo* represent the values measured on locks of undyed untreated hair. The higher the ΔΕ* value, the better the colour uptake is. The values of the colouring uptake ΔΕ * are given in the table hereinafter:

It is noted that the dyeing process according to the invention using the compositions according to the invention makes it possible to produce a satisfactory and significant colour uptake whatever the ortho- methoxypheno l o f formula (I) used.

Claims

1 . Process for dyeing keratin fibres, in particular human keratin fibres such as the hair, in which said fibres are treated, in one or more steps, with one or more cosmetic compositions containing, taken together or separately in said composition(s), the following ingredients :

a) one or more ortho-methoxypheno l(s) o f formula (I) below or an enantiomer or diastereoisomer thereo f, in salified or non-salified form, optionally in aglycone form:

in which formula (I) the substituents :

• R¹ represents :

- a hydrogen atom,

- a halogen atom,

- a carboxyl radical,

- an alkyl carboxylate or alkoxycarbonyl radical,

- an optionally substituted amino radical,

- an optionally substituted and linear or branched alkyl radical,

- an optionally substituted and linear or branched alkenyl radical,

- an optionally substituted cycloalkyl radical,

- an alkylcarbonyl radical,

- a carboxaldehyde radical,

- an alkoxy radical,

- an alkoxyalkyl radical,

- an alkoxyaryl radical, it being possible for the aryl group to optionally substituted,

- an aryl radical, - a substituted aryl radical,

- a radical comprising one or more silicon atoms,

• R² to R⁴, which may be identical or different, represent:

- a hydrogen atom,

- a halogen atom,

- a hydroxyl radical,

- a carboxyl radical,

- an alkyl carboxylate or alkoxycarbonyl radical,

- an optionally substituted amino radical,

- an optionally substituted and linear or branched alkyl radical,

- an optionally substituted and linear or branched alkenyl radical,

- an optionally substituted cycloalkyl radical,

- an alkylcarbonyl radical,

- a carboxaldehyde radical,

- an alkoxy radical,

- an alkoxyalkyl radical,

-an alkoxyaryl radical, it being possible for the aryl group to be optionally substituted,

- an aryl radical,

- a substituted aryl radical,

- a radical comprising one or more silicon atoms,

b) one or more manganese salt(s) and/or oxide(s) or one or more zinc salt(s) and/or oxide(s), c) hydrogen peroxide or one or more hydrogen peroxide-generating system(s),

d) one or more (bi)carbonate(s) or one or more (bicarbonate- generating system(s), and

optionally e) one or more alkalinizing agent(s) different from the bicarbonate(s) .

2. Dyeing process according to the preceding claim, characterized in that the ortho-methoxypheno l(s) o f formula (I) is (are) :

R¹ represents :

- a hydrogen atom,

- a halogen atom,

- a carboxyl radical,

- an alkyl carboxylate or alkoxycarbonyl radical,

- an optionally substituted and linear or branched alkyl radical,

- an optionally substituted and linear or branched alkenyl radical,

- an optionally substituted cycloalkyl radical,

- an alkylcarbonyl radical,

- a carboxaldehyde radical,

- an alkoxy radical,

R² to R⁴, which may be identical or different, represent:

- a hydrogen atom,

- a halogen atom,

- a hydroxyl radical,

- a carboxyl radical,

- an alkyl carboxylate or alkoxycarbonyl radical,

- an optionally substituted amino radical,

- an optionally substituted and linear or branched alkyl radical,

- an optionally substituted and linear or branched alkenyl radical,

- an optionally substituted cycloalkyl radical,

- an alkylcarbonyl radical,

- a carboxaldehyde radical,

- an alkoxy radical.

3. Dyeing process according to any one of the preceding claims, characterized in that the ortho-methoxypheno l(s) is (are) of formula (la) or an enantiomer or diastereoisomer thereof, in salified or non-salified form, optionally in aglycone form:

which formula (la)

R¹ represents

an alkoxy radical, preferably C i -C₆ alkoxy radical, such as methoxy,

a hydrogen atom,

• R² represents

an alkoxy radical, preferably C i -C₆ alkoxy radical, such as methoxy,

a linear or branched, preferably C i -C₆ , alkyl radical, such as methyl, or

a hydrogen atom;

• R³ represents

a) a hydrogen atom,

b) a hydroxyl group,

d) an alkenyl group chosen from:

i) R₅-C(0)-(CH=CH)_n-(*) with

n representing an integer inclusively between 1 and 4, preferably n = 1 and

* denoting the point of attachment of said group to the rest of the mo lecule; ii) R₅-0-(ALK)_p-(CH=CH)_n-(*) with

R₅ , n and * being as defined previously,

ALK representing a linear or branched, divalent (C i -C₆), preferably (C ₁ -C₂), alkylene radical, such as methylene, and

p = 0 or 1 , preferably 1 ; and

iii) the arylalkenyl(alkyl) group of formula below :

in which formula (iii) :

* is as defined previously,

p representing an integer inclusively between 0 and 4, preferably p is 0 or 2,

representing a single bond or a double bond,

q, which may be identical or different, being 0 or 1 , preferably q= l , ALK, which may be identical or different, representing a linear or branched, divalent (C i -C₆), preferably (C 1 -C2), alkylene group, such as methylene.

4. Dyeing process according to either one of Claims 1 and 2, characterized in that the ortho-methoxyphenol(s) is (are) of formula (lb) or an enantiomer or diastereoisomer thereof, in salified or non-salified form, optionally in aglycone form:

in which formula (lb):

• R² represents

a hydrogen atom or

an alkoxy radical, preferably Ci-C₆ alkoxy radical, such as methoxy, or

a linear or branched, preferably Ci-C₆, alkyl radical, such as methyl,

• R⁴ represents

a hydroxyl radical or

an alkoxy radical, preferably Ci-C₆ alkoxy radical, such as methoxy.

5. Dyeing process according to any one of the preceding claims, characterized in that the ortho-methoxyphenol(s) is (are) of formalae 1 to 19:

bis(4- hydroxy- 3 -met hoxybenzylidene)butanedioic diacid

1

4

4-[3-hydroxyprop - 1 - en- 1 -yl]-2-methoxyphenol

5

2-methoxy-4-methylphenol

6

2-met ^Ihoxxy-4r-ethylphenol

7

2-methoxy-4-propylphenol

8

4-hydroxymethyl-2-methoxyphenol

1 OH

9

4-(3-hydroxypropyl)-2-methoxyphenol

10

4-(2-hydroxy-3-mⁱe 'thoxyphenyl)butan-2-one

-but-2-ene- 1 ,4-diylbis(2-methoxyphenol

6. Dyeing process according to any one of the preceding claims, characterized in that the ortho-methoxypheno l(s) is (are) natural, more particularly chosen from extracts of animals, of bacteria, of fungi, of algae, of plants and of fruits.

7. Dyeing process according to any one of the preceding claims, characterized in that:

- the manganese salts and/or oxides, ingredient b), are chosen from: i) manganese oxides and

ii) halides, sulfates, phosphates, nitrates and perchlorates, carboxylic acid salts, such as gluconates, and also mixtures thereof, and

- the zinc salts and/or oxides, ingredient b), are chosen from zinc sulfate, zinc gluconate, zinc chloride, zinc lactate, zinc acetate, zinc glycinate and zinc aspartate;

and, more particularly, the salts b) are carboxylic acid salts o f manganese.

8. Dyeing process according to any one of the preceding claims, characterized in that the ingredient c) is hydrogen peroxide or urea peroxide.

9. Dyeing process according to any one of the preceding claims, characterized in that the (bi)carbonate(s), ingredient d), is (are) alkali metal, alkaline-earth metal or ammonium (bi)carbonate(s) .

10. Dyeing process according to any one of the preceding claims, characterized in that the alkaline agent(s) different from the bicarbonate(s), ingredient e), is (are) chosen from:

- aqueous ammonia,

- alkano lamines,

- oxyethylenated ethylenediamines,

- oxypropylenated ethylenediamines,

- inorganic or organic hydroxides,

- alkali metal silicates,

- amino acids, and

- the compounds o f form I) below:

N W N

/ \

(Π)

in which formula (II) :

- W is a divalent (C i - C s)alkylene group, preferably a propylene group, which is optionally substituted in particular with a hydroxyl group or a C 1 - C4 alkyl radical;

- R_a, R_b, R_c and R_d, which may be identical or different, represent a hydrogen atom or a C 1 - C4 alkyl or C 1 - C4 hydroxyalkyl radical;

preferably, the alkaline agent(s) e) is (are) chosen from alkano lamines, in particular monoethano lamine.

1 1 . Dyeing process according to any one of the preceding claims, characterized in that it is carried out in one step and that it consists in applying, to the keratin fibres, an aqueous composition comprising the ingredients a), b), c), d) and optionally e), as defined according to any one of the preceding claims .

12. Dyeing process according to any one of Claims 1 to 10, characterized in that it is carried out in two steps and that it consists in applying, to said fibres, a composition comprising the ingredients a), b) and c), as defined according to any one of Claims 1 to 8 , and then, in a second step, in applying, to said fibres, a composition comprising the ingredients d) and optionally e), as defined according to any one of Claims 1 , 9 and 10.

13. Dyeing process according to any one of Claims 1 to 10, characterized in that it is carried out in two steps and that it consists in applying, to said fibres, a composition comprising the ingredients a) and b), as defined according to any one of Claims 1 to 7, and then, in a second step, in applying, to said fibres, a composition comprising the ingredients c), d) and optionally e), as defined according to any one of Claims 1 and 8 to 10.

14. Dyeing process according to any one of Claims 1 to 10, characterized in that it is carried out in two steps and that it consists in applying, to said fibres, a composition comprising the ingredient b), as defined according to either one of Claims 1 and 7, and then, in a second step , a composition comprising the ingredients a), c), d) and optionally e), as defined according to any one o f Claims 1 and 8 to 10.

15. Cosmetic composition for dyeing keratin fibres, containing the compounds a), b), c), d) and optionally e), as defined according to any one of Claims 1 to 10.

16. Multicompartment device, characterized in that it comprises from 2 to 5 compartments containing from 2 to 5 compositions, in which are distributed the ingredients a), b), c), d) and optionally e), as defined according to any one of Claims 1 to 9 , said compositions being aqueous or pulverulent, at least one of these compositions being aqueous .