FR3130585A1 - Composition comprising a particular direct dye and henna - Google Patents

Abstract

Composition comprising a particular direct dye and henna The present invention relates to a composition comprising henna and at least one direct dye chosen from nitrobenzene direct dyes and anionic or nonionic anthraquinone direct dyes comprising an amine function in position 1.

Description

Composition comprising a particular direct dye and henna

The present invention relates to a composition comprising henna and at least one direct dye chosen from nitrobenzene direct dyes and anionic or nonionic anthraquinone direct dyes comprising an amine function in position 1.

The present invention also relates to a process for dyeing keratin fibres, in particular human keratin fibers such as the hair, using the composition of the invention.

For a long time, many people have sought to change the color of their hair, and in particular to color it, for example, in order to hide their white hair.

To permanently color human keratin fibers, so-called permanent coloring methods, also called oxidation coloring, have been developed. They use dye compositions containing oxidation dye precursors, generally called oxidation bases. These oxidation bases are colorless or weakly colored compounds which, associated with oxidizing products, can give rise by a process of oxidative condensation to colored compounds which remain trapped inside the fiber.

The second type of coloring is the so-called semi-permanent coloring or direct coloring. It consists in applying to the keratin fibers direct dyes which are colored and coloring molecules having an affinity for said fibers. Given the nature of the molecules used, they rather remain on the surface of the fiber and penetrate relatively little inside the fiber, in comparison with the small molecules of oxidation dye precursors. The main advantages of this type of coloring is that it does not require an oxidizing agent, which limits the degradation of the fibres, and that it does not use dyes with a certain reactivity, hence limiting the risks of intolerance.

The first hair dyes were semi-permanent. One of the best-known natural dyes is that derived from the henna plant.

Henna provides a red-orange color to white hair, and a "warm" color, that is to say copper to red, to brown hair.

However, the coloring process using henna is complicated to implement. It is first made a kind of "paste", often called "poultice", from ground or powdered henna leaves that are then diluted at the time of use with hot water. and said paste is then applied to the keratin fibres.

This process using said paste has drawbacks. During the preparation and application of the composition to the keratin fibres, it is not always possible to obtain a satisfactory impregnation due to the poor consistency of the composition obtained from the coarsely ground powder. In addition, it is very difficult to hope to reproduce the colors exactly because the Lawsone content very often varies from one batch to another, and from different ground materials.

Also, the pause time is long. It can vary from several tens of minutes to several hours (one night) depending on the desired intensity, without being able to control the result. The result varies depending on the fibers to be colored and the henna raw material used. As much as the color obtained on brown hair has a natural effect, white hair is colored an unsightly and unnatural orange color ("Hair preparations", Kirk-Othmer Encyclopedia of Chemical Technology, John Wiley & Sons, Inc.).

In general, for these various reasons, the colorations obtained are not homogeneous between the root and the tip (high selectivity) or from one fiber to another (The Science of Hair Care, C. Bouillon, J. Wilkinson, 2d Ed., CRC Press, Taylor & Francis Group; Boca Raton, London, pp. 236-241 (2005)).

It is known to use combinations of henna with direct dyes.

We have, however, realized that any direct dye does not allow when combined with henna to color the hair with brown shades.

The choice of particular direct dyes has proven to be essential in order to obtain a coloration with brown shades of the keratin fibers.

Thus there is a real need to develop a process for dyeing keratin fibres, using a natural dye such as henna, which does not have the disadvantages mentioned above.

The composition according to the invention comprising henna as defined below and at least one direct dye as not defined below makes it possible to obtain brown colorations which are powerful and reproducible.

Furthermore, this henna/direct dye(s) combination of the invention makes it possible to improve the rise, tenacity and selectivity and/or to improve the predictability and reproducibility of the results.

It also makes it possible to obtain new textures of coloring product based on natural dye (cream, gel) allowing a cleaner application and easier to locate on the hair and easier to rinse.

The composition according to the invention also makes it possible to obtain compositions that persist in shampoos.

The invention therefore relates to a composition comprising
henna and
at least one direct dye chosen from benzene nitro dyes and anionic or nonionic anthraquinone dyes comprising an amine function in position 1 or mixtures thereof.

The present invention also relates to a multi-compartment device or kit comprising the composition according to the invention.

Other objects, characteristics, aspects and advantages of the invention will appear even more clearly on reading the description and the examples which follow.

In what follows, and unless otherwise indicated, the limits of a range of values are included in this range, in particular in the expressions “ included between ” and “ ranging from … to … ”.

The expression “ at least one ” used in the present description is equivalent to the expression “ one or more ”.

Henna

According to the present invention, “henna” means a henna plant powder and/or a henna plant extract.

The henna plant powder and/or extract comprises in particular lawsone and/or one of its glucosylated precursors.

Preferably, the henna used according to the present invention is in the form of an extract.

Method for preparing the useful henna extract according to the invention

Henna extract is generally obtained from the leaves of Lawsonia inermis (Henna), in particular reduced to powder.

The process for preparing henna extract includes the following steps:
(i) the hydrolysis of an aqueous dispersion of henna at a pH ranging from 1 to 3.5, preferably for 1 minute to 24 hours, more preferably from 20 minutes to 24 hours, such as one hour, then
(ii) the extraction of the aqueous phase obtained in step (i) with an organic solvent immiscible with water or a mixture of organic solvents immiscible with water (liquid-liquid extraction), in which said organic solvent or said mixture has a polarity index of 3.5 or more.

In step (i) , the henna is mixed with water.

According to one embodiment, the first step (i) uses henna which is immersed in acidic water, preferably for at least 5 minutes at a temperature of 15 to 40°C, preferably 20 to 30°C, better at 25 to 30°C, especially for 20 minutes to 24 hours. According to another variation, the henna is mixed with hot water (35°C – 80°C) for several minutes (like 2 minutes-30 minutes).

According to a variant, the henna leaf or the dry henna leaf powder is mixed with water with stirring and/or sonication and/or heating to obtain a homogeneous aqueous dispersion.

In particular, the quantity by weight of the henna leaf, reduced to powder or not, preferably to powder, ranges from 1% to 50%, preferably from 5% to 25%, better still from 7 to 15% by weight relative to the weight of water, such as 10% by weight based on the weight of water.

Step (i) is carried out in the presence of an (in)organic acid or a mixture of (in)organic acids.

The term “ (in)organic acid ” means an organic acid or an inorganic acid.

A mixture of (in)organic acids means a mixture of organic acids, or a mixture of inorganic acids or a mixture of organic(s) and inorganic(s).

The term " organic acid " is as defined above.

By “ inorganic acid ” is meant an acid, ie a compound capable of releasing a cation or proton H ⁺ , or H ₃ O ⁺ in aqueous media, which does not include a carbon atom.

More particularly, the acid used in the acid hydrolysis stage i) is chosen from hydrochloric acid HCl, hydrobromic acid HBr, sulfuric acid H ₂ SO ₄ , alkyl sulphonic acids (C ₁ -C ₆ )Alk-S(O) ₂ OH such as methylsulfonic acid and ethylsulfonic acid; Ar-S(O) ₂ OH arylsulfonic acids such as benzenesulfonic acid and toluenesulfonic acid; (C ₁ -C ₆ )alkoxysulfinic acids (C ₁ -C ₆ )Alk-OS(O)OH such as methoxysulfinic acid and ethoxysulfinic acid; aryloxysulfinic acids such as tolueneoxysulfinic acid and phenoxysulfinic acid; phosphoric acid H ₃ PO ₄ ; triflic acid CF ₃ SO ₃ H and tetrafluoroboric acid HBF ₄ , and the carboxylic acids of formula (I) as defined below.

According to one embodiment of the invention, step (i) is carried out in the presence of an organic acid such as acetic acid or a (hydroxyl) (C ₁ -C ₁₀ )carboxylic acid, or in the presence of an inorganic acid such as hydrochloric or sulfuric acid, and preferably in the presence of an organic acid such as a (hydroxyl) (C ₁ -C ₁₀ )carboxylic acid such as citric acid, lactic acid, glycolic acid, or tartaric acid, and better still citric acid.

By “(hydroxyl)(C ₁ -C ₁₀ )carboxylic acid” is meant a carboxylic acid containing at least one carboxy group (C(O)OH), (preferably 1 to 5 carboxy groups, in particular 3) connected to a alkyl group comprising from 1 to 10 carbon atoms, preferably from 1 to 6 and better still from 1 to 4, said alkyl group being optionally substituted by one or more hydroxy groups (preferably 1 to 5 hydroxy groups, and more preferably one) .

The pH during the hydrolysis stage (i) ranges in particular from 1 to 3.5, more particularly from 1 to 3, better still from 2 to 3, even better from 2.5 to 3, such as 3 .

The henna used in the invention is pure natural henna, in particular in the form of leaves, preferably reduced to powder.

The henna powder can be sieved to obtain particles having upper limit sizes corresponding to the size of the orifices or meshes of the sieve, ranging in particular from 500 μm to 180 μm (35 to 80 mesh (US)) According to a particular embodiment of the invention, the size of the henna powder particles is fine. According to the invention, a particle size of less than or equal to 500 μm is advantageous. More preferably, the powder consists of fine particles having sizes ranging from 50 to 300 μm, and more particularly from 10 to 200 μm

Generally, said henna particles have a moisture content ranging from 0 to 10% by weight relative to the total weight of the powder.

More specifically, the henna is red henna ( Lawsonia inermis, alba ).

Red henna comes from the leaves of a thorny shrub (Lawsonia alba , Lawsonia inermis) of the Lythraceae family ("Dyes, Natural", Kirk-Othmer Encyclopedia of Chemical Technology, "Henna" Encyclopedia Britannica). It is based on the principle of coloring with the active agent lawsone: 2-hydroxy-1,4-naphthoquinone. Lawsone [83-72-7] (CI Natural Orange 6; CI 75420), also known as isojuglone.

In a particular embodiment, decontaminated henna is used in step (i). In such a case, the process for preparing the henna extract comprises an additional step (i ₀ ) consisting in decontaminating the henna, which is carried out before step (i).

In step (i ₀ ), the henna is cleaned to remove contaminants such as microorganisms.

The number of microorganisms is on average between 10 ⁵ and 10 ⁷ microorganisms per gram of powder or leaves before decontamination.

Any method known to those skilled in the art can be used provided that the number of microorganisms is reduced, in particular by a factor of 10 2 to 10 ⁶ , that is to say preferably between 99.9 and 99.99999%.

The term " micro-organisms " includes in particular fungi, molds, spores and bacteria.

Examples of decontamination processes are hot air drying, microwaves, dry heat, steam sterilization, ethanol floatation and irradiation.

According to one embodiment, after step (i) of the process for preparing the henna extract, the aqueous extract is preferably filtered through a Büchner funnel having a sieve size of 5 to 100 μm (US) , more particularly 10 μm (US). According to a particular embodiment, the filtration step is carried out after step (i) and before step (ii) .

In step (ii) , the aqueous extract of the henna is separated by liquid-liquid extraction using a water-immiscible organic solvent or a mixture of water-immiscible organic solvents. In other words, the aqueous phase obtained in step (i) is mixed with one or more water-immiscible organic solvent(s), in which the water-immiscible organic solvent(s) miscible in water or the mixture of organic solvents immiscible in water has a polarity index of 3.5 or more, preferably in a solvent or mixture of solvents/aqueous phase weight ratio ranging from 10 to 1, better from 5 to 1, like 2.5.

By "water-immiscible solvent" is meant a solvent having a solubility in water at 25°C of 15g per 100g of water or less, preferably of 10g per 100g of water or less, more preferentially from 0.05 g to 10 g per 100 g of water, and even more preferentially from 0.05 to 9 g per 100 g of water.

Preferably, the extraction step (ii) is carried out at a temperature of 15°C to 40°C, more preferably 20°C to 30°C, more preferably 25°C to 30°C.

The water-immiscible solvent or the mixture of water-immiscible organic solvents preferably has a polarity index of 3.8 or more, better still 3.8 to 5, even better still 4 to 5. , like 4.4.

The solvents used for the liquid-liquid extraction are immiscible organic solvents which have a polarity index of 3.5 or more, and are preferably chosen from:
i) chloroform,
ii) (C ₁ -C ₆ )alkyl esters, such as those described below, better still (C ₁ -C ₆ )alkyl acetates, better still ethyl or butyl acetate, and
iii) C ₄ -C ₁₀ alcohols such as n-butanol, n-pentanol, n-hexanol, n-heptanol, n-octanol, preferably C ₄ -C ₈ alcohols, more preferably n-butanol.

The (C ₁ -C ₆ )alkyl esters preferably correspond to the formula:
R'-C(O)-O-R''
wherein R' and R'' each independently represent a C ₁ -C ₆ alkyl group,
and more preferably to the formula:
H ₃ CC(O)-O-R''
with R'' representing a C ₁ -C ₆ alkyl group.

The liquid-liquid extraction step (ii) is preferably carried out with a (C ₁ -C ₆ )alkyl ester as defined above, such as a (C ₁ -C ₆ )alkyl acetate, or a C ₄ -C ₈ alcohol, more preferably with ethyl acetate or n-butanol, better still with ethyl acetate.

The extraction time can vary from 1 minute to 24 hours, in particular from 5 minutes to 5 hours, and more particularly from 10 to 60 minutes.

The extraction temperature may be in the range from 5° C. to 60° C., in particular from 15° C. to 40° C., more particularly from 20° C. to 35° C., better still from 25° C. to 30° C. °C, such as a temperature of 27-30°C.

In a preferred embodiment, the process for preparing the henna extract comprises steps (i ₀ ) , (i) and (ii) .

In another embodiment, the process for preparing the henna extract comprises steps (i) and (ii) and a filtration step after step (i) and before step (ii) .

According to one embodiment, after step (ii) of the process for preparing the henna extract, the solvent or the mixture of solvents is removed, preferably by evaporation, in particular at a temperature ranging from 10° C. to 50 °C, under vacuum. The crude henna extract can then be dried, for example in a desiccator with P ₂ O ₅ or silica gel.

According to a preferred embodiment, the composition according to the invention comprises
- a henna extract obtained by the method as described above and
- at least one direct dye chosen from benzene nitro dyes and anionic or nonionic anthraquinone dyes comprising an amine function in position 1 or mixtures thereof.

Preferably, this extract comprises:
• 10-50%, preferably 10-49%, better 10-48%, more preferably 10-46%, specifically 10-45%, and even more preferably 13-44% by weight of 2,3,4,6 -tetrahydroxy acetophenone (THA) relative to the total weight of the extract; And
• 5-30%, preferably 5-27%, better 5-25%, even better 5-25%, specifically 5-24%, and even more preferably 7-24% by weight of 2-hydroxy-1,4 -naphthaquinone (lawsone) relative to the total weight of the extract,
with a THA/Lawsone weight ratio greater than 1, preferably greater than 1.5 and better still greater than 1.6.

More preferably the henna extract used in the invention comprising:
• 10-50%, preferably 35-49%, better 35-48%, more preferably 37-46%, specifically 38-45%, and even more preferably 39-44% by weight of 2,3,4,6 -tetrahydroxy acetophenone (THA) relative to the total weight of the extract; And
• 5-30%, preferably 15-27%, more preferably 17.5-25%, more preferably 18.5-25%, specifically 17.5-25%, more specifically 19-24%, and even more preferably 19 ,5-24% by weight of 2-hydroxy-1,4-naphthaquinone (lawsone) relative to the total weight of the extract,
with a THA/Lawsone weight ratio greater than 1, preferably greater than 1.5 and better still greater than 1.6.

Better still, the henna extract used in the invention comprises:
• 35-49%, preferably 35-48%, better 37-46%, even better 38-45%, and even more preferably 39-44% by weight of 2,3,4,6-tetrahydroxy acetophenone (THA) relative to the total weight of the extract; And
• 15-27%, preferably 17.5-25%, better 17.5-25%, even better 18.5-24%, and more preferably 19.5-24% by weight of 2-hydroxy-1, 4-naphthaquinone (lawsone) relative to the total weight of the extract, with a THA/Lawsone weight ratio greater than 1, preferably greater than 1.5 and better still greater than 1.6.

In a preferred embodiment, the THA/Lawsone weight ratio is in the range from 1.1 to 2.5, preferably from 1.5 to 2.2, in particular from 1.6 to 2.1 .

According to a particular embodiment, the composition according to the invention comprises henna in a content varying from 0.1 to 88% by weight, preferably from 0.5 to 80% by weight, better still from 1 to 75% by weight, relative to the total weight of the composition.

According to a particular embodiment, the composition according to the invention comprises the useful henna extract according to the invention in a content varying from 0.1 to 20% by weight, preferably from 0.5 to 15% by weight. , better still from 1 to 10% by weight, relative to the total weight of the composition of the invention.

Direct dyes

The composition according to the invention comprises at least one direct dye chosen from anionic or nonionic anthraquinone dyes comprising an amine function in position 1.

By nonionic anthraquinones is meant anthraquinones which may comprise cationizable groups, such as amine functions, but not comprising a group bearing a permanent charge, such as quaternary ammonium groups. The amine group(s) of the anthraquinones useful according to the invention are therefore primary, secondary or tertiary amines.

By anionic anthraquinones is meant anthraquinones bearing anionic groups, in particular carboxylic or sulphonic groups.

According to a first embodiment, the anionic or nonionic anthraquinone dyes according to the invention comprise an amine function in position 1 and an amine function in position 4.
- According to a first variant, these two amine groups are primary amine functions.
- According to a second variant, at least one of the amine functions is substituted by a benzosulphonic group.
- According to a third variant, the two amine groups in position 1 and 4 are substituted by a benzosulphonic group.

Preferably, the anionic or nonionic anthraquinone dyes comprising an amine function in position 1 and an amine function in position 4 are chosen from the following anthraquinones of formula (I) or (II) :

in which R ¹ and R ^2, which are identical or different, denote a hydrogen or a -CH ₂ CHOHCH ₂ OH group.

in which :
R ³ and R ⁴ , which are identical or different, denote a hydrogen or a hydrocarbon-based alkyl chain, preferably a hydrocarbon-based alkyl chain, better still a methyl or butyl chain;
M denotes a counter ion chosen from an alkali metal or an ammonium, preferably chosen from an alkali metal, more preferably M denotes a sodium counter ion.

According to a second embodiment, the anionic anthraquinone dyes comprise an amine function in position 1 substituted by a benzosulphonic group.
According to this embodiment, the anionic anthraquinone dyes comprising an amine function in position 1 are chosen from the dyes of formula(III)next

in which :
R ⁵ denotes a hydrogen atom, a hydroxy -OH group or a hydrocarbon alkyl chain, preferably a methyl chain;
Mdenotes a counter ion chosen from an alkali metal or an ammonium, preferably chosen from an alkali metal, better still M denotes a sodium counter ion.

Preferably, the anionic or nonionic anthraquinone dyes comprising an amine function in position 1 are chosen from HC Blue 14, disperse violet 1 and EXT violet 2.

According to another embodiment, the composition of the invention comprises at least one nitrobenzene direct dye.

Preferably, the nitrobenzene direct dyes are chosen from those substituted by an oxygen atom and a nitrogen atom in the ortho position to each other.

Among the nitrobenzene direct dyes, mention may be made of: HC Blue 2, HC Yellow 2, HC Red 3,4-hydroxypropylamino-3-nitrophenol, N,N′- bis-(2-hydroxyethyl)-2-nitro-phenylenediamine. Preferably, the nitrobenzene dye useful according to the invention is HC Blue 2.

Preferably, the direct dyes useful according to the invention are chosen from anionic or nonionic anthraquinone dyes comprising an amine function in position 1.

The useful dyes according to the invention can be acid or base salts. Acids can be inorganic or organic. Preferably, the acid is hydrochloric acid which leads to chlorides.

According to one embodiment, the composition of the invention comprises the direct dye(s) useful according to the invention in a content varying from 1% to 50% by weight, better still from 2 to 35% by weight, better still, from 5 at 25% by weight relative to the total weight of the composition of the invention.

According to one embodiment, the composition of the invention comprises the anthraquinone direct dye(s) useful according to the invention in a content varying from 1% to 50% by weight, better still from 2 to 35% by weight, better still, from 5 to 25% by weight relative to the total weight of the composition of the invention.

According to one embodiment, the composition of the invention comprises the nitrobenzene direct dye(s) useful according to the invention in a content varying from 1% to 50% by weight, better still from 2 to 35% by weight, better still from 5 to 25% by weight relative to the total weight of the composition of the invention.

Saccharide(s)

The composition according to the invention may also comprise one or more (poly)saccharide(s) as described below.

The saccharides can be chosen from mono-, oligo- or polysaccharides. They can be in reduced form.

In particular, the saccharides or reduced saccharides useful in the process of the invention are solid, ie they are not liquids or syrups at ambient temperature (25° C.) and at atmospheric pressure (1.013×10 ⁵ Pa).

By “ monosaccharide ” is meant a sugar comprising only a single unit, ie not comprising a glycosidic covalent bond with another sugar.

Preferably, the " monosaccharides " useful in the process according to the invention are chosen from:
• " aldoses " or polyhydroxyaldehydes, preferably comprising between 4 and 6 carbon atoms such as erythose or threose (4 carbon atoms), ribose, arabinose, xylose or lyxose (5 carbon atoms) , allose, altrose, glucose, mannose, gulose, idose, galactose and talose (6 carbon atoms);
• " ketoses " or polyhydroxyketones preferably comprising between 4 and 6 carbon atoms such as erythrulose (4 carbon atoms), ribulose or xylulose (5 carbon atoms), psicose, fructose, sorbose and tagatose (6 carbon atoms); And
• the reduced forms of aldoses and ketoses as defined above are also called “ sugar alcohols ” or “ alditols ”. They are in particular chosen from erythritol, glucitol or sorbitol, mannitol and xylitol, preferably sorbitol.

By “ sugar alcohol ” is meant “ polyols ” generally obtained by reduction of aldose or ketose monosaccharides as defined above or of oligo or polysaccharide complexes as defined below in which the aldehyde or ketone group(s) of the monosaccharide units are reduced ie replaced by a hydroxy group.

Preferably, the sugars useful according to the invention and in particular the sugar alcohols are of plant origin.

It is understood that by aldoses, ketoses and sugar alcohols, is also meant their optical isomers, their anomers and their L (levorotatory) and D (dextrorotatory) forms.

More preferably, the monosaccharides useful according to the invention contain 6 carbon atoms.

By “ oligosaccharide ” is meant a sugar in which the monosaccharides as defined above are joined together by a covalent glycosidic bond to lead to a simple polymer comprising from 2 to 10 monosaccharide units.

In particular, the oligosaccharides are chosen from disaccharides such as sucrose, trehalose and raffinose, lactose, cellobiose and maltose; maltodextrins, cyclodextrins; and their reduced forms such as isomaltulose, trehalulose, isomalt, maltitol, and lactitol.

It is understood that by oligosaccharides is also meant their optical isomers, their anomers and their L (levorotatory) and D (dextrorotatory) forms.

By " polysaccharides " is meant oligosaccharides which have at least 11 monosaccharide units. Preferably, the polysaccharides of the invention comprise between 20 and 100,000 monosaccharide units.

The polysaccharides useful according to the invention can be chosen from those derived from the following sugars: glucose; galactose; arabinose; rhamnose; mannose; xylose; fucose; anhydrogalactose; galacturonic acid; glucuronic acid; mannuronic acid; galactose sulphate; anhydrogalactose sulphate.

The polymers with sugar units of the invention can be natural or synthetic.

They can be non-ionic, anionic, amphoteric or cationic.

According to a particular embodiment, the saccharides useful according to the invention are chosen from native gums such as:
• tree or shrub exudates including: gum arabic (branched polymer of galactose, arabinose, rhamnose and glucuronic acid); ghatti gum (polymer derived from arabinose, galactose, mannose, xylose and glucuronic acid); karaya gum (polymer derived from galacturonic acid, galactose, rhamnose and glucuronic acid); tragacanth (or tragacanth) gum (polymer of galacturonic acid, galactose, fucose, xylose and arabinose);
• gums from algae such as: agar (polymer from galactose and anhydrogalactose); alginates (polymers of mannuronic acid and glucuronic acid); carrageenans and furcellerans (polymers of galactose sulphate and anhydrogalactose sulphate);
• gums from seeds or tubers such as: guar gum (polymer of mannose and galactose); locust bean gum (polymer of mannose and galactose); fenugreek gum (polymer of mannose and galactose); tamarind gum (polymer of galactose, xylose and glucose); konjac gum (polymer of glucose and mannose);
• plant extracts such as: cellulose (glucose polymer), modified or not; and starch (polymer of glucose) modified or not;
• microbial gums such as: xanthan gums (polymer of glucose, mannose acetate, mannose/pyruvic acid and glucuronic acid); gellan gums (polymer of partially acylated glucose, rhamnose and glucuronic acid); scleroglucan gums (polymer of glucose); pullulan gums, curdlar gums, grifolan gums, lentinan gums, schizophyllan gums, spirulinan gums and krestin gums.

Within the meaning of the present invention, the term " microbial gums " means substances synthesized by fermentation of sugars by microorganisms.

According to a preferred embodiment, the polysaccharides useful according to the invention are chosen from gums, better still, from microbial gums. Preferably, xanthan gums, scleroglucan gums, or a mixture thereof are used.

Preferably, said saccharides are soluble polysaccharides in the composition. Even more preferably, said polysaccharides are water-soluble.

According to one embodiment, the saccharide(s) are present in the composition of the invention.

According to a variant, the saccharide(s) are present in a separate composition which is mixed with the composition of the invention before its application to the keratin fibres.

Thus, the polysaccharide(s) are present in the composition of the invention and/or in a composition with which the composition of the invention is mixed before its application to the keratin fibers.

According to a variant, the polysaccharides present in the composition of the invention are chosen from maltodextrin, modified or unmodified starches and modified or unmodified celluloses, preferably from modified or unmodified starches.

According to another variant, the polysaccharides present in the composition with which the composition of the invention is mixed before being applied are chosen from dextrose, oligosaccharides such as maltodextrin, polysaccharides such as modified or unmodified starches, and modified or unmodified celluloses, microbial gums and mixtures thereof, more preferably from microbial gums and mixtures thereof, preferably from xanthan and scleroglucan gums and mixtures thereof.

According to one embodiment, the composition(s) comprising the saccharide(s) comprise an amount of saccharides varying from 10 to 98% by weight, preferably from 20 to 95% by weight, more preferably from 70 to 95% by weight with respect to to the total weight of the composition.

When the composition of the invention is mixed with a composition comprising at least one saccharide, the composition applied to the hair preferably comprises the saccharide(s) in a content varying from 0.05% to 30% by weight, and more preferably from 0.5% to 25% by weight, better still from 1% to 20% by weight, better still from 3% to 15% by weight relative to the total weight of the composition.

According to one embodiment, the composition of the invention is anhydrous (contains less than 3% water) and the composition with which the composition of the invention is mixed before its application to the keratin fibers comprises water.

According to a preferred variant, the composition of the invention is in the form of an aqueous gel.

According to one procedure, the composition of the invention and the water are mixed in a water/powder ratio preferably ranging from 1 to 10, even more preferably 2 to 5, even better still 4.

Preferably, the composition comprising water further comprises a saccharide as described previously.

According to a preferred variant, the composition comprising water is a hydroalcoholic composition. Preferably, the hydroalcoholic composition comprises at least one alcohol chosen from benzyl alcohol, ethanol and their mixtures and water.

Preferably, the composition comprising water is in the form of a gel further comprising at least one (poly)saccharide as defined above and at least one alcohol chosen from benzyl alcohol, ethanol and mixtures thereof.

According to this embodiment, the composition according to the invention applied to the hair is obtained by extemporaneous mixing at the time of use of at least:
- a composition comprising henna as defined above and at least one direct dye as defined above, and optionally at least one polysaccharide preferably chosen from maltodextrin or modified or unmodified starches, or a mixture thereof, better still from modified starches or no, and
- a composition comprising water, at least one (poly)saccharide, preferably chosen from microbial gums and their mixtures, even better, from xanthan and scleroglucan gums and their mixtures and at least one alcohol chosen from benzyl alcohol, ethanol and mixtures thereof.

According to a preferred variant, the composition according to the invention applied to the hair is obtained by extemporaneous mixing at the time of use of at least:
- a composition comprising the henna extract as defined above and at least one direct dye as defined above, and optionally at least one polysaccharide preferably chosen from maltodextrin or modified or unmodified starches, or their mixture, better still from modified or unmodified starches, and
- a composition comprising water, at least one (poly)saccharide, preferably chosen from microbial gums and their mixtures, even better, from xanthan and scleroglucan gums and their mixtures and at least one alcohol chosen from benzyl alcohol, ethanol and mixtures thereof.

According to one embodiment, the composition applied to the hair comprises henna extract in a content varying from 0.01 to 5% by weight, preferably from 0.05 to 3% by weight, better still from 0.1 to 2% by weight relative to the total weight of the composition.

According to one embodiment, the composition applied to the hair comprises lawsone in a content varying from 0.001 to 2% by weight, preferably from 0.005 to 1% by weight, better still from 0.01% to 0.5%, even better still from 0.01% to 0.4% by weight relative to the total weight of the composition.

According to one embodiment, the composition applied to the hair comprises the direct dye(s) useful according to the invention in a content ranging from 0.05% to 10% by weight, preferably from 0.1 to 5% by weight, better still from 0.2 to 3% by weight relative to the total weight of the composition.

According to one embodiment, the composition applied to the hair comprises the anthraquinone direct dye(s) useful according to the invention in a content ranging from 0.05% to 10% by weight, preferably from 0.1 to 5% by weight. , better still from 0.2 to 3% by weight relative to the total weight of the composition.

According to one embodiment, the composition applied to the hair comprises the nitrobenzene direct dye(s) useful according to the invention in a content ranging from 0.05% to 10% by weight, preferably from 0.1 to 5% by weight, better still from 0.2 to 3% by weight relative to the total weight of the composition.

According to one embodiment, the pH of the composition applied to the hair preferably ranges from 2.5 to 7, more particularly from 2.5 to 6.5, better still from 2.7 to 5.

Process

Another object of the invention is a hair coloring process comprising a step of applying the composition according to the invention as described above to the hair.

According to one embodiment, the step of applying the composition according to the invention may be followed by a step of rinsing the hair.

The method of the invention may comprise the application of one or more metal salt(s), preferably one or more titanium salt(s).

The metal salt(s) may be present in the composition of the invention or in a separate composition.

The application of the metal salt(s) can then be done simultaneously or separately, said metal salt being in the composition according to the invention or in a separate composition.

According to a first embodiment, the method comprises the preparation of a composition (A) comprising one or more metal salts, preferably one or more titanium salt(s), henna, preferably a particular henna extract such as defined above and at least one direct dye chosen from benzene nitro dyes and anionic or nonionic anthraquinone dyes comprising an amine function in position 1 as defined above or mixtures thereof, and its application to the hair.

According to a second embodiment, the method comprises:
- the application of a composition (A') comprising one or more metal salts, preferably one or more titanium salt(s), and
- the application of a composition (B) comprising henna, preferably a henna extract as defined above and at least one dye chosen from benzene nitro dyes and anionic or nonionic anthraquinone dyes comprising an amine function in position 1 as defined above or mixtures thereof, on the hair.

In this latter embodiment, composition (A′) can be applied before composition (B) or vice versa. Preferably:
(a) composition (A') is first applied,
(b) then composition (B) is applied, and
(c) the hair is rinsed,
rinsing may occur between the two steps (a) and (b) .

Preferably, a rinsing step is carried out after step (a) and before step (b) .

Metal salt – titanium salt

According to a preferred embodiment, the useful hair dyeing process according to the invention uses at least one metal salt, preferably at least one transition metal salt, more preferably at least one metal salt of the d block. of the periodic table.

According to a preferred embodiment, the hair coloring process according to the invention uses at least one titanium salt.

The titanium salt(s) used in the process of the invention can be organic or inorganic. Preferably, the titanium salt(s) is or are organic.

By “ organic titanium salt ”, is meant within the meaning of the present invention the salts themselves resulting from the action of at least one organic acid on the Ti.

By “ organic acid ”, we mean an acid, ie a compound capable of releasing a cation or proton H ⁺ , or H ₃ O ⁺ in aqueous media, which comprises at least one C ₁ -C ₂₀ hydrocarbon chain, optionally unsaturated, linear or branched, a (hetero)cycloalkyl or (hetero)aryl group, and at least one acid chemical function chosen in particular from the carboxyl group COOH, sulfuric SO ₃ H, SO ₂ H, and phosphoric PO ₃ H ₂ , PO _{4 H2} . The denomination “ organic acid ” also covers the corresponding salts.

In particular, mention may be made of aliphatic carboxylic acids, (hetero)cycloalkyl or heterocycloaryl carboxylic acids and their salts.

In particular, the organic acid(s) useful for forming the organic titanium salt(s) of the invention is (are) chosen from the carboxylic acids of formula (I ) :

formula (I) in which:
- A represents a monovalent group when n is 0 or polyvalent when n is greater than or equal to 1; it is a hydrocarbon group comprising from 1 to 50 carbon atoms, better still from 1 to 20 carbon atoms, saturated or unsaturated, cyclic or non-cyclic, aromatic or non-aromatic, optionally interrupted by one or more heteroatoms and/or optionally substituted in particular by one or more hydroxy and/or amino groups;
preferably A represents a monovalent (C ₁ -C ₆ )alkyl or polyvalent (C ₁ -C ₆ )alkylene group optionally substituted by one or more hydroxy and/or amino groups; And
- n represents an integer ranging from 0 to 10, preferably from 0 to 5, better still from 0 to 2.

Preferably, these carboxylic acids of formulas (I) are such that A represents a monovalent (C ₁ -C ₆ )alkyl or polyvalent (C ₁ -C ₆ )alkylene group optionally substituted by one or more hydroxy groups, and n represents a integer ranging from 0 to 5, such as 0, 1 or 2.

According to this embodiment, the carboxylic acids of formulas (I) can be alpha-hydroxy acids such as lactic acid, glycolic acid, tartaric acid or citric acid.

Preferably, the organic titanium salt resulting from the action of one or more organic acid(s) as defined above, preferably carboxylic acid(s) of formula (I ) as defined above, is an optionally charged (in particular negatively) complex in which the titanium is complexed with one or more carboxylate group(s) of carboxylic acid(s).

More preferably, the organic titanium salt(s) used in the invention is (are) chosen from those of formula (IA) below:

formula(IA)in which :
•ATis identical to that defined in formula (I);
•notis 0, 1, 2, 3 or 4,
•not'Andnot'', identical or different, are worth 1, 2, 3 or 4 with n'+n'' being worth 6;
•M ₁ AndM ₂ , which are identical or different, represent a hydrogen atom or a cationic counter-ion, in particular chosen from alkali metal cations such as Na or K, alkaline-earth metal cations such as Ca, and organic cations such as ammonium, preferably ammonium;
•Ti Y _not'' denoting Ti(OH)_not''or Ti(O)_n''/2or Ti(OH)_m1(O)_m2with m1+m2 = n’’.

Preferably, the radical A of the compound (IA) as defined above represents a monovalent (C ₁ -C ₆ )alkyl or polyvalent (C ₁ -C ₆ )alkylene group optionally substituted by one or more hydroxy groups or one or more amino groups , preferably by one or more hydroxy groups, and n represents an integer ranging from 0 to 4, better still from 0 to 2.

More particularly, the carboxylic acid(s) used to form the organic titanium salt(s) of the invention are chosen from α-hydroxy acids. Preferably, the acid is chosen from citric acid, lactic acid, malic acid, tartaric acid, and glycolic acid, or their mixture, more preferably chosen from lactic and glycolic acid, preferably lactic acid.

Preferably, the organic salt(s) of titanium is (are) chosen from those of formula (IB) below:

formula (IB) in which:
● L' and L'' , identical or different, represent a divalent (hetero)arylene, (C ₁ -C ₆ )alkylene, (C ₂ -C ₆ )alkenylene group, said alkylene and arylene groups being optionally substituted by one or several atoms or groups chosen from halo, (C ₁ -C ₄ )alkyl, hydroxy, thiol, and (di)(C ₁ -C ₄ )(alkyl)amino, carboxy, and/or optionally interrupted by one or more heteroatoms such than oxygen;
preferably L' and L'' are identical and represent a methylene or ethylene group optionally substituted by a (C ₁ -C ₄ )alkyl group;
● X' and X'' , identical or different, represent a heteroatom such as oxygen, sulfur or amino R ^c -N with R ^c representing a hydrogen atom or a (C ₁ -C ₄ )alkyl group;
preferably X' and X'' are identical and represent an oxygen atom;
● Y and Y' , identical or different, are as defined for X' and X'' ;
preferably Y and Y' are identical and represent an oxygen atom;
● R ^a and R ^b , which are identical or different, represent a hydrogen atom, or a (C ₁ -C ₆ )alkyl, (C ₂ -C ₆ )alkenyl or (hetero)aryl group;
particularly R ^a and R ^b , which are identical, represent a hydrogen atom or a (C ₁ -C ₄ )alkyl group, preferably hydrogen;
● M ⁺ , identical or different, represents a cationic counter-ion such as an alkali metal (Na, K), alkaline-earth metal (Ca), or organic cation such as ammonium, preferably ammonium.

Preferably, the organic titanium salt(s) used in the dyeing process according to the invention is (are) chosen from the salts of formula (IB) , better still from the salts of dihydroxybis(lactato)titanium IV such as that of the following formula:

.

By " inorganic titanium salt " is meant within the meaning of the present invention the salts themselves resulting from the action of an inorganic acid on the Ti.

By “ inorganic acid ” is meant an acid which does not contain any carbon atoms apart from carbonic acid.

According to a particular embodiment of the invention, the titanium salt(s) is (are) inorganic. It(s) is(are) particularly chosen from titanium halides, titanium sulphates and titanium phosphates. Preferably the inorganic titanium salts are salts of Ti(II), Ti(III) or Ti(IV), more particularly Ti(III) or Ti(IV), even more preferentially Ti(IV).

According to another embodiment, the titanium salt or salts is (are) organic salts of titanium, and better still organic salts of Ti(IV).

According to an advantageous embodiment of the invention, the titanium salt is an organic salt of Ti and preferably consists of a Ti(IV) atom and 2 to 3 molar equivalents of at least one carboxylic acid of formula (I) .

According to a preferred embodiment, the organic titanium salt or salts are chosen from dihydroxybis(lactato)titanium(IV) salts as defined above.

Preferably, the metal salt(s) as defined above is (are) present in a total amount preferably ranging from 0.01% to 20% by weight, more preferably from 0.1 to 10% by weight, better still from 0.5 to 5% by weight relative to the total weight of composition (A) or (A′) .

Carboxylic acids of formula (I)

The hair dyeing process according to the invention can implement one or more carboxylic acid(s) of formula (I) or its salts as defined previously.

By “ carboxylic acid ” is meant a compound comprising at least one carboxylic acid group –C(O)OH, of formula (I) as defined above, preferably comprising 1 to 4 carboxylic acid groups, more preferably comprising 1 or 2 carboxylic acid groups.

Preferably, these carboxylic acids of formulas (I) are such that A represents a monovalent (C ₁ -C ₆ )alkyl or polyvalent (C ₁ -C ₆ )alkylene group optionally substituted by one or more hydroxy groups, and n represents a integer ranging from 0 to 5, such as 0, 1 or 2.

The carboxylic acids of formula (I) useful according to the invention are preferably chosen from alpha-hydroxy acids.

As preferred examples of carboxylic acids of formula (I) , mention may be made of glycolic acid, citric acid, lactic acid, tartaric acid or one of their salts, preferably citric acid. , lactic acid or a salt thereof.

These carboxylic acids of formula (I) optionally used in the process are distinct from those forming a complex with the metal salts or the titanium salts as described above. It being understood that these acids of formula (I) can be identical to or different from the acids of formula (I) complexed with titanium.

According to a first embodiment, this or these carboxylic acids are different from the carboxylic acids complexed with Ti. For example, if the carboxylic acid complexed with titanium is lactic acid or its carboxylate salt (lactate), the carboxylic acid used is different from lactic acid.

According to a second embodiment, this or these carboxylic acids are identical to the carboxylic acids complexed with Ti. For example, if the carboxylic acid complexed with titanium is lactic acid or its carboxylate salt (lactate), the carboxylic acid used is also lactic acid. This embodiment is particularly preferred.

The salts of the acids of formula (I) can be salts of organic or mineral bases or of basifying agents. Preferably the salts are sodium hydroxide, ammonia or potash salts or organic amine salts such as alkanolamines.

When one or more carboxylic acids of formula (I) as defined above is or are present, its or their total amount preferably ranges from 0.01% to 30% by weight, more preferably from 1 to 20% by weight, better still from 3 to 15% by weight relative to the total weight of the composition in composition (A) , (A′) and/or (B) .

When one or more carboxylic acids of formula (I) as defined above is or are present, they are preferably found in composition (A) or (A')

According to one embodiment, the compositions (A) , (A′) used in the process according to the invention comprise water.

When water is present, its content preferably ranges from 0.1% to 95% by weight, more preferably from 1 to 90% by weight, better still from 5 to 85% by weight relative to the total weight of the composition la container.

Compositions (A) and (A') may comprise one or more organic solvents.

By organic solvent is meant an organic substance capable of dissolving or dispersing another substance without chemically modifying it.

As an organic solvent, mention may be made, for example, of C ₁ -C ₄ alcohols, such as ethanol and isopropanol; polyols and polyol ethers such as 2-butoxyethanol, propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and monomethyl ether, hexylene glycol, as well as aromatic alcohols such as benzyl alcohol or phenoxyethanol.

When a solvent or organic solvents are present, its (their) amount varies from 0.1 to 20% by weight, and even more preferably from 0.5 to 10% by weight, relative to the total weight of the composition in which it(s) is(are), in particular in the composition (A) and (A′) .

Additive(s)

The compositions described above can also comprise various adjuvants conventionally used in compositions for coloring the hair, such as anionic, cationic, nonionic, amphoteric or zwitterionic polymers different from the polysaccharides as described above; inorganic or organic thickening agents, and in particular anionic, cationic, nonionic and amphoteric polymeric associative thickeners; antioxidant agents; penetrants; sequestering agents; perfumes ; tampons; dispersing agents; conditioning agents other than the fatty substances mentioned above of the invention such as, for example, volatile or non-volatile, modified or unmodified silicones, ceramides; film-forming agents; preservatives; opacifying agents; and their mixtures.

pH of compositions

According to a preferred embodiment of the invention, the compositions (A) and (A′) used in the process of the invention are aqueous compositions. According to this embodiment, the pH of compositions (A) and (A′) is acidic, ie less than 7.0. Preferably, the pH of these compositions is less than 5.0, particularly this pH ranges from 1.5 to 4.5, more particularly from 2 to 4, preferentially from 2 to 3.5.

The pH of these compositions can be adjusted to the desired value by means of acidic or alkaline agent(s) usually used in dyeing keratin fibres, such as the hair, or even using buffer systems known to those skilled in the art. Preferably, hydrochloric acid, lactic acid, or citric acid or arginine or sodium hydroxide is used.

Device or “kit”

The present invention also relates to a multi-compartment device or “kit”. Advantageously, this kit comprises from 2 to 5 compartments containing from 2 to 3 compositions.

According to one embodiment, the multi-compartment device comprises:
- a first compartment containing a composition comprising henna, preferably henna extract as defined above and at least one direct dye as defined above, and optionally at least one polysaccharide preferably chosen from maltodextrin or modified starches or no, or their mixture, better among modified or unmodified starches, and
- a second compartment containing a composition comprising water, at least one (poly)saccharide, preferably chosen from microbial gums and their mixtures, even better, from xanthan and scleroglucan gums and their mixtures and at least one alcohol selected from benzyl alcohol, ethanol and mixtures thereof.

According to another embodiment, the multi-compartment device comprises:
- a first compartment containing a composition comprising henna, preferably henna extract as defined above and at least one direct dye as defined above, and optionally at least one polysaccharide preferably chosen from maltodextrin or modified starches or no, or their mixture, better among modified or unmodified starches,
- a second compartment containing a composition comprising water, at least one (poly)saccharide, preferably chosen from microbial gums and their mixtures, even better, from xanthan and scleroglucan gums and their mixtures and at least one alcohol selected from benzyl alcohol, ethanol and mixtures thereof and
- A third compartment comprising one or more metal salts, preferably one or more salt(s) of titanium, and optionally one or more carboxylic acids of formula (I) .

Said device is suitable for dyeing keratinous fibres, such as the hair.

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

The device mentioned above can also be equipped with a means making it possible to deliver the desired mixture to the hair, for example such as the devices described in patent FR 2586913.

The following example serves to illustrate the invention without however being limiting.

Examples

Example 1

Preparation of the compositions and application to keratin fibers

The following compositions were prepared in the proportions indicated in grams of active material per 100 g of composition, unless otherwise indicated:

▬Compositions A’

A' (invention) Dihydroxybis(ammonium lactato) titanium(IV) 2.75 Lactic acid 7.5 Dioctadecyl oxide 10 scleroglucan gum 1.3 Water Qsp 100

▬ Compound B :

C1
invention C2
comparative C3
invention C4
comparative C5
invention Henna extract with 24% by weight of lawsone and 44% by weight of 2,4,5,6-tetrahydroxy acetophenone (THA) at 14% in 86% starch 20 20 20 20 20 HC Blue n°2 15 - - - - HC Blue n°16 - 15 - - - EXT. Purple 2 - - 5 - - Hydroxyanthraquinone aminopropyl methyl morpholinium methosulfate - - - 5 - Disperse purple 1 - - - - 10 Starch Qsp 100

D Benzyl alcohol 2.2 Ethanol 8 Blend of xanthan gum and scleroglucan 1.7 Water Qsp 100

Composition A′ was applied to locks of natural Caucasian hair containing 90% white hair (BN) at the rate of 4 g of composition per gram of hair and left for 15 minutes at 33° C. under occlusion then rinsed with water .

Then, on the resulting locks, compositions B1 to B4 were obtained by mixing each of compositions C1 to C4 with composition D , in a C:D ratio of 1:10 and then they were applied. 2 g of this mixture B1 to B4 are used for 1 g of locks. The mixture is left to stand for 30 minutes at 40° C. under occlusion and then rinsed. The locks are then shampooed and dried.

Color assessment

The locks treated with the composition of the invention (coloration process with compositions A then B1 or A then B3 ) have brown shades unlike the locks treated with the comparative compositions comprising direct dyes outside the invention (coloring process with compositions A then B2 or A then B4 ). Furthermore, the locks treated with the composition of the invention also exhibit a more intense coloring and with a better increase in the coloring compared with the locks treated with the comparative compositions comprising direct dyes outside the invention.

Process Color Intensity process A then B1 (invention) warm brown ++++ process A then B2 (comparative) Light green + process A then B3 (invention) cool brown +++ process A then B4 (comparative) copper +

We also treated locks of natural Caucasian hair containing 90% white hair (BN) directly with composition B5 obtained by mixing composition C5 with composition D , in a C5:D ratio of 1:10.

2 g of B5 mixture are used for 1 g of locks. The mixture is left to stand for 30 minutes at 40° C. under occlusion and then rinsed. The locks are then shampooed and dried.

Brown locks are also obtained.

The locks thus colored are then subjected to a test of several repeated shampoos so as to evaluate the tenacity (the persistence) of the coloring obtained with the shampoos.

The locks are washed using a standard shampoo respectively at T=0 (ie immediately after application of the coloring composition to the locks).
The locks of hair are then rinsed. The following shampoos are carried out on the locks thus obtained. The locks are compared at T=0, at 5 shampoos and at 10 shampoos.

The persistence of the color of the locks is evaluated in the L*a*b* system, with a Minolta CM3600D spectrocolorimeter (illuminant D65, angle 10°, specular component included).

In this L*a*b* system, L* represents the color intensity, a* indicates the green/red color axis and b* the blue/yellow color axis.

The persistence of the coloring is evaluated by the difference in color ΔE between the colored locks before shampoo, then after having undergone 5 and 10 shampoos according to the protocol described above. The lower the value of ΔE, the more the color persists to shampoos.

Process I* To* b* ΔE Color process B5 (invention) t0 51.1 8.4 8.1 16.4 Chestnut After 5 shampoos 53.3 7.5 9.8 1.7 After 10 shampoos 53.9 6.4 8.8 1.9

The locks of hair colored with the coloring composition B5 according to the invention and washed with five or ten shampoos have low values of ΔE, therefore good persistence of the color.
Thus, the hair is colored in a brown shade and the coloring is persistent with shampoos.

Example 2

Preparation of the compositions and application to keratin fibers

The following compositions were prepared in the proportions indicated in grams of active material per 100 g of composition, unless otherwise indicated:

▬ Compound B :

C6
invention Henna extract with 24% by weight of lawsone and 44% by weight of 2,4,5,6-tetrahydroxy acetophenone (THA) at 14% in 86% starch 30 Disperse Purple 1 5.25 Starch QS100

From Benzyl alcohol 2.2 Ethanol 8 Blend of xanthan gum and scleroglucan 1.7 Mixture of lactic acid, phosphoric acid, sodium phosphate Qsp pH=2.2 Water Qsp 100

Composition B6 obtained by mixing composition C6 with composition D′ , in a C6:D′ ratio of 1:10, was applied to locks of 90% white (BN) natural hair. 2 g of this B6 mixture are used for 1 g of locks. The mixture is left to stand for 30 minutes at 40° C. under occlusion and then rinsed. The locks are then shampooed and dried.

Color assessment

The coloring of the hair is evaluated in the L*a*b* system, with a Minolta CM3600D spectrocolorimeter (illuminant D65, angle 10°, specular component included).

In this system, L* stands for clarity. The lower the value of L*, the darker and more powerful the color obtained. Chromaticity is measured by the a* and b* values, where a* represents the red/green axis and b* represents the yellow/blue axis.

The rise in color is represented by the color difference ΔE between the uncolored lock and the colored lock: the higher the value of ΔE, the greater the rise in color. This value is calculated from the following equation (i):

In equation (i), L*, a* and b* represent the values measured on locks of colored hair, and L ₀ *, a ₀ * and b ₀ * represent the values measured on locks of uncolored hair .

Colorimetric values and color rise ΔE are listed in the table below:

Process I* To* b* ΔE Color before coloring 63.4 1 16 - - process B6 34.4 4.4 -0.8 29.0 Intense warm brown

The locks treated with composition B6 of the invention have brown shades. The coloring obtained is moreover intense and a good increase in coloring is observed on the locks thus colored.

Claims (22)

Composition comprising
henna and
at least one direct dye chosen from benzene nitro dyes and anionic or nonionic anthraquinone dyes comprising an amine function in position 1 or mixtures thereof. Composition according to the preceding claim, in which
henna is a henna extract comprising:
- 10-50% by weight of 2,3,4,6-tetrahydroxyacetophenone (THA) relative to the total weight of the extract, and
- 5-30% by weight of 2-hydroxy-1,4-naphthoquinone (lawsone) relative to the total weight of the extract,
with a THA/Lawsone weight ratio greater than 1, preferably greater than 1.5 and better still greater than 1.6. Composition according to any one of the preceding claims, in which the nitrobenzene direct dye(s) are chosen from HC Blue 2, HC Yellow 2, HC Red 3, 4-hydroxypropylamino-3-nitrophenol, N,N'- bis-(2-hydroxyethyl)-2-nitro-phenylenediamine, preferably the nitrobenzene dye useful according to the invention is HC Blue 2. Composition according to any one of the preceding claims, in which the anionic or nonionic anthraquinone direct dye(s) are chosen from comprising an amine function in position 1 and an amine function in position 4. Composition according to any one of the preceding claims, in which the anionic anthraquinone direct dye(s) comprise an amine function in position 1 substituted by a benzosulfonic group. Composition according to any one of the preceding claims 1 to 3, in which the anionic or nonionic anthraquinone direct dye(s) comprising an amine function in position 1 are chosen from HC Blue 14, disperse violet 1 and EXT purple 2. Composition according to any one of the preceding claims, comprising the direct dye(s) chosen from benzene nitro dyes, anionic or nonionic anthraquinone dyes comprising an amine function in position 1, in a content varying from 1% to 50% by weight , preferably from 2 to 35% by weight, better still 5 to 25% by weight relative to the total weight of the composition. Composition according to any one of the preceding claims 2 to 7, in which the henna extract has a THA/lawsone weight ratio ranging from 1.1 to 2.5, more preferably from 1.5 to 2.2, better still from 1 .6 to 2.1. Composition according to any one of the preceding claims 2 to 8, in which the henna extract has a THA/lawsone weight ratio ranging from 1.1 to 2.5, more preferably from 1.5 to 2.2, better still from 1 .6 to 2.1. Composition according to any one of the preceding claims, comprising henna in a content varying from 0.1 to 88% by weight, better still from 0.05 to 80% by weight, even better from 1 to 75% by weight relative to the total weight of the composition. Composition according to any one of the preceding claims 2 to 10, in which the henna extract is obtained by:
(i) hydrolysis of an aqueous dispersion of henna at pH ranging from 1 to 3.5, preferably for 1 minute to 24 hours, more preferably from 20 minutes to 24 hours, and
(ii) extraction of the aqueous phase obtained in step (i) with an organic solvent immiscible with water or a mixture of organic solvents immiscible with water (liquid-liquid extraction), in which said organic solvent or said mixture has a polarity of 3.5 or more. Composition according to any one of the preceding claims comprising one or more saccharides, preferably chosen from maltodextrin, modified or unmodified starches and modified or unmodified celluloses, more preferably from modified or unmodified starches. Composition according to the preceding claim, characterized in that it is in the form of an aqueous gel. Hair dyeing process implementing a step of applying the composition according to any one of the preceding claims to the hair. Hair coloring process according to the preceding claim comprising
- a step of mixing a composition according to any one of claims 1 to 12 with a composition comprising water, at least one (poly)saccharide, preferably chosen from microbial gums and mixtures thereof, even better, from xanthan and scleroglucan gums and mixtures thereof and at least one alcohol chosen from benzyl alcohol, ethanol and mixtures thereof; Then
- a step of applying the composition resulting from the mixture to the hair. Process for coloring the hair according to any one of claims 14 or 15 implementing the application to the hair of at least one metal salt, preferably at least one transition metal salt, more preferably at least one metal salt of block d, better, at least one titanium salt. Hair coloring process according to the preceding claim comprising:
- the application of a composition (A′) comprising the metal salt(s), preferably the transition metal salt(s), more preferably the metal salt(s) of the block d, better titanium salt(s), and
- the application of a composition (B) as defined in any one of claims 1 to 13. Hair coloring process according to the preceding claim, in which:
(a) composition (A') is first applied,
(b) then composition (B) is applied, and
(c) the hair is rinsed,
rinsing may occur between the two steps (a) and (b). Hair dyeing process according to any one of claims 16 to 18 using at least one metal salt chosen from titanium salts, preferably the titanium salt is that of the following formula:
Process for dyeing the hair according to any one of claims 16 to 19, in which the metal salt(s) is (are) present in a total quantity ranging from 0.01% to 20% by weight, more preferably from 0.1 to 10% by weight, better still from 0.5 to 5% by weight relative to the total weight of the composition in which they are found. Hair dyeing process according to any one of Claims 16 to 20, using one or more carboxylic acid(s) of the following formula (I) or its salts:

in which :
- A represents a monovalent group when n is 0 or polyvalent when n is greater than or equal to 1; it is a hydrocarbon group comprising from 1 to 50 carbon atoms, saturated or unsaturated, cyclic or non-cyclic, aromatic or non-aromatic, optionally interrupted by one or more heteroatoms and/or optionally substituted in particular by one or more hydroxy groups and/or amino;
preferably A represents a monovalent (C ₁ -C ₆ )alkyl or polyvalent (C ₁ -C ₆ )alkylene group optionally substituted by one or more hydroxy and/or amino groups; And
- n represents an integer ranging from 0 to 10, preferably from 0 to 5, better still from 0 to 2. Device with several compartments, comprising:
- a first compartment containing a composition as defined in any one of claims 1 to 12, and
- a second compartment containing a composition comprising water, at least one (poly)saccharide, preferably chosen from microbial gums and their mixtures, even better, from xanthan and scleroglucan gums and their mixtures and at least one alcohol selected from benzyl alcohol, ethanol and mixtures thereof.