FR2989269A1 - PIGMENT COMPOSITION COMPRISING AMINO ACID DERIVATIVES AND COSMETIC USES - Google Patents

Abstract

The invention relates to a pigment composition in powder form comprising: - a pigment, - at least two N-acylamino acids optionally in the form of salts, the two N-acylamino acids being of different natures, and - an amino acid chosen from cysteine, cystine, methionine, a salt thereof and a mixture thereof, a process for its preparation and a cosmetic composition comprising it.

Description

The present invention relates to a pigment composition comprising amino acid derivatives useful for the preparation of cosmetic products. In cosmetics, tactile sensation is a very important factor to evaluate. The ability to spread evenly when applying to the skin without abrasion and without feeling of roughness is crucial. The sensation of abrasion and roughness is responsible for physical irritation and causes roughness of the skin and skin inflammation. Affinity is classified in the criteria of finishing of the cosmetic products allowing to obtain a lightness of charge on the skin, a sensation and a soft application and a great safety. The cosmetic products are usually prepared by mixing basic formulations, and in particular pigment compositions which make it possible to give the cosmetic product the desired color. Thus, pigment compositions not only soft to the touch but also having a good affinity with the skin and / or the hair are sought. In this regard, the application FR 2 795 949 describes a powder, which may be a surface-treated pigment carrying a first layer A and a second surface treatment agent coating layer B, each formed on at least one part the surface of the powder particles. The surface treatment agent of the layer A is solid at ambient temperature and contains at least one compound selected from a reactive organopolysiloxane, a polyolefin, a hydrogenated lecithin, including its salts, an N-acylamino acid, including its salts, a fatty acid, including its salts and a dextrin ester of fatty acids. The surface treatment agent of layer B is liquid at room temperature and contains at least one compound selected from an organopolysiloxane modified at a single terminal end by a functional group, an alkylsilane modified at one end only by a functional group, and a branched fatty acid. This surface-treated powder is described as being unctuous and highly dispersible in an oleophilic liquid, these two properties coming largely from the chain length of the B-surface treatment agent. No. 2,785,906 discloses pigments coated with a mixture comprising at least 14 acyl amino acids or their salts, the amino acids being capable of being obtained by total hydrolysis of animal or plant proteins.

This demand teaches that the higher the proportion of glycine, alanine and serine, the greater the affinity for the skin or the hair. The development of pigment compositions not only soft to the touch but also having a good affinity with the skin and the hair is necessary. [Pigment composition] For this purpose, according to a first object, the invention provides a powdery pigment composition comprising: at least one pigment, at least two N-acylamino acids optionally in the form of salts, the two N-acylamino acids being different natures, and an amino acid selected from cysteine, cystine, methionine, a salt thereof and a mixture thereof. It has been discovered that such a pigment composition is soft to the touch and has a good affinity with the skin and hair (keratin fibers). It is therefore particularly suitable for being introduced into a cosmetic composition. The pigment The pigment composition may comprise one or more pigments.

The pigment present in the pigment composition according to the invention may be an organic, inorganic or hybrid organic-inorganic pigment or a mineral filler or a mixture thereof. These are typically inorganic pigments. The inorganic pigment may, for example, be chosen from titanium dioxide, zinc dioxide, zirconium or cerium oxides, as well as iron or chromium oxides, manganese violet, ultramarine blue, hydrate of chromium and ferric blue, and their mixtures. The preferred inorganic pigments are iron oxides, especially red iron oxide, yellow iron oxide, brown iron oxide, black iron oxide, titanium dioxide and mixtures thereof.

The organic pigment may for example be selected from carbon black, such as D & C black No. 2, red organic pigments, such as D & C Red No. 6, No. 7, No. 21, No. 27, No. ° 28, No. 30, No. 33, No. 36, No. 40, and Cochineal Carmine, blue organic pigments, such as copper phthalocyanine and FD & C Blue No. 1 lacquer, and organic pigments yellow, such as D & C Yellow No. 10, FD & C Yellow No. 5 and 6, and mixtures thereof.

As mineral fillers suitable for the implementation of the invention, there may be mentioned talc, kaolin, alumina, silica, and nacres such as borosilicates or mica, natural or synthetic, and optionally coated with titanium oxide (TiO2), iron oxide (Fe2O3) (red, yellow or black), chromium oxide (Cr2O3) or a mixture of these oxides.

Generally, the pigment composition comprises from 0.01% to 30% by weight, typically from 0.1 to 20% by weight, preferably from 0.5 to 10% by weight of pigment relative to the total weight of the pigment composition . N-acylamino acids or a salt thereof An N-acylamino acid is an amino acid bearing an amino group and / or imino acylated. The two N-acylamino acids of the pigment composition are of different natures, i.e., they differ in the nature of the acyl group and / or the amino acid group (i.e., by the nature of the side chain of the amino acid group). Preferably, they differ in the nature of the amino acid group. The amino acid which constitutes the N-acylamino acid may be a single amino acid or a mixture of several different amino acids.

Glycine, alanine, p-alanine, valine, leucine, isoleucine, phenylalanine, proline, threonine, serine, arginine, histidine, lysine, aspartic acid, glutamic acid, tyrosine, methionine, cystine, cysteine are examples of amino acid groups for independently each of the N-acylamino acids. If there are L, D or DL isomers for the amino acid group of N-acylamino acid, these isomers can be used individually or in combination. The naturally occurring L-isomer is preferred. The acyl group of each of the N-acylamino acids is typically an acyl radical of a fatty acid. The N-acylamino acid is typically capable of being obtained by forming an amide linkage between the amino function of an amino acid and the carboxylic acid function of a fatty acid.

The fatty acid is generally a saturated or unsaturated fatty acid having 1 to 23 carbon atoms. Thus, the constituent fatty acids of each of the N-acylamino acids are generally long-chain fatty acids such as caprylic acid, capric acid, lauric acid, myristic acid, isomyristic acid, acid palmitic acid, isopalmitic acid, stearic acid, isostearic acid, arachidic acid, undecylenic acid, oleic acid, myristoleic acid, elaidic acid, linolic acid, acid linolenic acid, arachidonic acid, coconut oil fatty acid, beef tallow fatty acid (fat), resin acid (abietic acid), etc.

Each of the N-acylamino acid can independently be used in the free form or in the form of one or more salts. The salt form can be illustrated by metal salts such as Na, K, Ba, Zn, Ca, Mg, Fe, Zr, Co, Al, Ti, etc., ammonium salts and salts of various alkanolamines such as monoethanolamine, diethanolamine, triethanolamine, 2-amino-2-methylpropanol, 2-amino-2-methyl-1,3-propanediol, triisopropanolamine, etc. Each of the N-acylamino acids independently independently has the following formula (I): R1- (CO) -NR3-CHR2- (CO) -O (M), /, (I), wherein: R1 represents an alkyl group or linear, branched or cyclic, typically linear, alkenyl having from 8 to 22 carbon atoms, R2 is a group selected from H, Me, (CH2) 3 -NH- (CNH) -NH2, CH2- (CO) -NH2 , CH2- (CO) -OH, CH2SH, (CH2) 2- (CO) -NH2, (CH2) 2- (CO) -OH, CH2-imidazolyl, CHMe-CH2-CH3, CH2-CHMe2, (CH2) 4-NH2, (CH2) 2-S-Me, CH2-phenyl, CH2-pyrrolidinyl, CH2-OH, CH (OH) -Me, CH2-indolyl, CH2-p-hydroxyphenyl and CHMe2, R3 represents H, or R3 and R2 together represent a divalent group - (CH2) 3-, M is selected from H, Na, K, Ba, Zn, Ca, Mg, Fe, Zr, Co, Al, Ti, NH4 and an alkanolamine onium such as monoethanolamine, diethanolamine, triethanolamine, 2-amino-2-methyl-propanol, 2-amino-2-methyl-1,3-propanediol and triisopropanolamine, m represents 1 when M is H or m represents the valence of The R2 groups correspond to the side chains of the natural amino acids. When R3 and R2 together represent a - (CH2) 3- divalent group, the N-acylamino acid is N-acylproline.

The N-acylamino acids are commercially available or can be synthesized by methods known to those skilled in the art. In one embodiment, one of the N-acylamino acids is an N-acylated glutamic acid, optionally in the form of a salt, in particular an N-cocoyl glutamic acid, optionally in salt form, in particular a sodium cocoyl glutamate, available commercially for example under the following trade names: Plantapon® ACGHC (BASF), Hostapon® CCG (Clariant), Amisoft® CS-11 (Ajinomoto) or Protelan® AGL 95 / C (Zschimmer & Schwarz).

In one embodiment, one of the N-acylamino acids is an N-acyl arginine optionally in salt form, especially N-lauroyl arginine, commercially available for example under the trade name Amisafe® AL-01 (Ajinomoto). The two embodiments above can advantageously be combined.

Application FR 2 785 906 teaches that an N-acylated glutamic acid (R 2 represents (CH 2) 2 (00) -OH in the formula (I) above) gives a soft tactile sensation but that its affinity for the skin and the hair is not satisfactory. On the other hand, N-acyl arginine optionally in salt form, in particular N-lauroyl arginine, is hydrophobic and induces a soft tactile sensation and has a better affinity for the skin than an N-acylated glutamic acid, but its affinity for the hair is not satisfactory. However, it has been demonstrated in the context of the present invention that a pigment composition comprising a pigment, an N-acylated glutamic acid, optionally in the form of a salt, and an N-acyl arginine, optionally in salt form, advantageously induces a sensation. soft touch and has a skin affinity greater than that of a composition comprising a pigment and an N-acylated glutamic acid, but free of N-acyl arginine, and that of a composition comprising a pigment and N-acyl acyl arginine, but free of N-acylated glutamic acid. A synergistic effect on the affinity of the pigment composition for the skin is therefore observed when the N-acylamino acids N-acyl arginine and N-acylated glutamic acid are combined. However, the hair affinity of a composition consisting of a pigment, N-acyl arginine and N-acyl glutamic acid remains low. This is why the pigment composition according to the invention comprises, in addition to two N-acylamino acids, a specific amino acid, as explained below. Generally, each of the N-acylamino acids represents from 0.01 to 20% by weight, in particular from 0.1 to 10% by weight, preferably from 0.5 to 5% by weight relative to the total weight of the pigment composition in powder form. - Amino acid selected from cysteine, cystine, methionine, a salt thereof or a mixture thereof All three amino acids have a sulfur side chain. They are commercially available.

These amino acids may be in the form of L, D isomers or a mixture thereof. The naturally occurring L-isomer is preferred. When the amino acid is in salt form, the nature of the counterion is not limited. For example, the counter-ion may be selected from Na, K, Ba, Zn, Ca, Mg, Fe, Zr, Co, Al, Ti, NH4 and an onion of alkanolamine, such as monoethanolamine, diethanolamine. triethanolamine, 2-amino-2-methyl-propanol, 2-amino-2-methyl-1,3-propanediol and triisopropanolamine. Preferably, cysteine, cystine, methionine, a salt thereof or a mixture thereof do not come from animal origin. They are preferably derived from biofermentation. This is an advantage because in the cosmetic field, we are looking for non-animal components. Preferably, the pigment composition comprises cystine or a salt thereof, especially L-cystine, which is commercially available, for example under the trade name L-cystine (Wacker) or AEC Cystine (A & E Connock). Cysteine, cystine, methionine, one of their salts or a mixture of these have a good affinity for the hair (which is generally explained by the sulfur nature of their side chain, which has a strong affinity for the hair including disulfide bridges). It has been demonstrated in the context of the present invention that the pigment composition according to the invention not only has a soft tactile sensation, but that it also has a good affinity for the skin and for the hair. Thus, the pigment composition according to the invention has the cumulative advantages of: a pigment composition comprising a pigment and two N-acylamino acids (free of an amino acid chosen from cysteine, cystine and methionine), a pigment composition comprising a pigment and an amino acid selected from cysteine, cystine and methionine (free of N-acylamino acid), without the disadvantages of each of the components taken alone.

Generally, the amino acid chosen from cysteine, cystine, methionine, a salt thereof or a mixture thereof represents from 0.01% to 20% by weight, in particular from 0.1% to 10% by weight, of preferably from 0.5 to 5% by weight relative to the total weight of the pigment composition in powder form. In one embodiment, the pigment composition in powder form consists of: at least one pigment, at least two N-acylamino acids optionally in the form of salts, the two N-acylamino acids being of different natures, and an amino acid selected from cysteine, cystine, methionine, a salt thereof and a mixture thereof. Other Additives The pigment composition may also contain other additives such as polyacrylates or polyacrylic acids, polyethoxylated or alkylated or fluorinated alkoxysilanes, surfactants, carboxylic acids comprising ethylene oxide chains, amino acids , chitosan, cellulose and its derivatives (cellulose ether, microcrystalline cellulose, carboxymethylcellulose and hydroxypropyl methylcellulose (HPMC), sugars such as galactoarabinan or xanthan gum, titanates, perfluorinated, alkylated and hydroxyl phosphates [Process for the preparation of the pigment composition] According to a second subject, the invention relates to the process for preparing the powdery powder composition defined above, comprising the following steps: a) mixing in a solvent: d at least one pigment, at least two N-acylamino acids optionally in the form of salts, both N-acylaminoacid e being of different natures, and an amino acid selected from cysteine, cystine, methionine, a salt thereof and a mixture thereof, and deposition or precipitation on the pigment of said at least two Nacylamino acids optionally in the form of of salts and said amino acid, b) filtration of the pigment composition, or evaporation of the solvent, drying and grinding to obtain the pigment composition in powder form.

The solvent is generally an aqueous, alcoholic or aqueous-alcoholic medium, the alcohol being, for example, ethanol. To minimize costs, an aqueous medium is preferred. The mixture of step a) is generally carried out under conditions, in particular of pH and of temperature, making it possible to solubilize the N-acylamino acids and the amino acid, without degrading them, then the conditions are adapted so that the components (at least two N-acylamino acids optionally in the form of salts, the two N-acylamino acids being of different natures, and an amino acid selected from cysteine, cystine, methionine, a salt thereof and a mixture thereof) precipitate or settle on the surface of the pigment. Step a) also includes deposition or precipitation of the components on the surface of the pigment. The mixture of the components of the pigment composition in a solvent of step a) can be carried out by simultaneous or separate mixing of the components.

When the mixture of the various components of the pigment composition is simultaneous, it is assumed that, in the pigment composition obtained, the surface of the pigment is at least partially covered with a layer comprising at least two N-acylamino acids, optionally in the form of salts, the two N-acylamino acids being of different natures, and an amino acid chosen from cysteine, cystine, methionine, one of their salts and a mixture thereof ("monolayer" organization, because the surface of the pigment is at least partially covered a layer comprising at least these three components). The mixture of the components of the pigment composition in a solvent of step a) can also be carried out by separate mixing of the components, which is generally preferred because the industrial implementation is facilitated and preserves the possible degradation of the components. during step a). In the processes below, "amino acid" means an amino acid selected from cysteine, cystine, methionine, a salt thereof and a mixture thereof.

When the mixture of the components of the pigment composition is separated, step a) typically comprises, according to a first alternative, the following steps: a1) mixing in a solvent at least one pigment and one or more first ( s) component (s) of the pigment composition chosen from one of the N-acylamino acids and the amino acid, a2) adaptation of the temperature and / or pH conditions so that the first component (s) (s) is deposited (s) at least partially on the surface of the pigment, a3) the addition to the mixture obtained at the end of step a2) of (s) the other (s) component (s) of the pigment composition, optionally in a solvent of the same or different nature of the solvent of step a1), a4) adaptation of the temperature and / or pH conditions so that the other component (s) is deposited at least partially on the surface of the pigment and / or on the surface of the first component (s).

For example, when the at least two N-acylamino acids, optionally in the form of salts, are added in a first step and then the amino acid in a second step, step a) of the process for preparing a pigment composition typically comprises the following steps: a1) mixing in a solvent at least one pigment and at least two N-acylamino acids optionally in the form of salts, a2) adapting the temperature and / or pH conditions so that the at least two Nacylamino acids optionally in the form of salts are deposited at least partially on the surface of the pigment, a3) the addition to the mixture obtained at the end of step a2) of the amino acid, optionally in a solvent of identical nature or different from the solvent of step a1). a4) adapting the temperature and / or pH conditions so that the amino acid is deposited at least partially on the surface of the pigment and / or on the surface of the at least two N-acylamino acids optionally in the form of salts.

According to this first alternative, it is assumed that the organization of the N-acylamino acids and of the amino acid on the surface of the pigment is: - either "monolayer" (as defined above), - or "bilayer" is that is, the pigment surface of the pigment composition in powder form is at least partially covered with a first layer comprising one or more first component (s) of the pigment composition selected from one of N-acylamino acids and the amino acid, and the first layer is at least partially covered with a second layer comprising the other component (s) of the pigment composition. Typically, in the example mentioned above in which the at least two N-acylamino acids optionally in the form of salts are added in a first step and then the amino acid in a second step, it is assumed that: either the surface of the pigment is covered at least partially of a layer comprising at least two N-acylamino acids optionally in the form of salts, the two N-acylamino acids being of different natures, and the amino acid, ie the surface of the pigment is at least partially covered with a first layer comprising at least two N-acylamino acids optionally in the form of salts, and the first layer is at least partially covered with a second layer comprising the amino acid. When the mixture of the components of the pigment composition is separated, step a) typically comprises, according to a second alternative, the following steps: a1) mixing in a solvent at least one pigment and a first component of the a pigment composition chosen from one of the N-acylamino acids and the amino acid, a2) the adaptation of the temperature and / or pH conditions so that the first component is deposited at least partially on the surface of the pigment, a3) the addition to the mixture obtained at the end of step a2) of a second component of the pigment composition chosen from one of the N-acylamino acids and the amino acid, but of a different nature from the first component, optionally in a solvent of the same or different nature of the solvent of step a1), a4) adaptation of the temperature and / or pH conditions so that the second component is deposited at least on the surface of the pigment and / or on the surface of the first component, a5) the adding to the mixture obtained at the end of step a4) of a third component of the pigment composition chosen from one of the N-acylamino acids and the amino acid, but of a different nature from the first and second components, optionally in a solvent of identical nature or different from the solvent of step a1) and a3), a6) adapting the temperature and / or pH conditions so that the third component is deposited at least partially on the surface of the pigment and / or on the surface of the first component and / or on the surface of the second component.

For example, when an N-acylamino acid, optionally in salt form, is added in a first step, then an N-acylamino acid, which may be in the form of a salt of a different nature, is added in a second stage, and then the amino acid in a third stage. step a) of the process for preparing a pigment composition comprises the following steps: a1) mixing in a solvent at least one pigment and a first N-acylamino acid, optionally in salt form, a2) adaptation temperature and / or pH conditions so that the first Nacylamino acid possibly in salt form is deposited at least partially on the surface of the pigment, a3) the addition to the mixture obtained at the end of step a2) of a second N-acylamino acid, optionally in salt form, but of a different nature from the first N-acylamino acid, optionally in a solvent of identical nature or different from the solvent of step a1), a4) adaptation of the conditions of temperature and / or pH so that the second Nacylamino acid possibly in salt form is deposited at least on the surface of the pigment and / or on the surface of the first N-acylamino acid, a5) the addition to the mixture obtained at the end of the step a4) of an amino acid selected from cysteine, cystine, methionine, a salt thereof and a mixture thereof, optionally in a solvent of the same or different nature of the solvent of step a1) and a3 ), a6) adapting the temperature and / or pH conditions so that the amino acid is deposited at least partially on the surface of the pigment and / or on the surface of the first N-acylamino acid and / or on the surface of the second N-acyl amino acid. According to this second alternative, it is assumed that the organization of the N-acylamino acids and of the amino acid on the surface of the pigment is: either "monolayer" (as defined above), or "bilayer", (as defined herein above), or "tricouche", that is to say that the surface of the pigment is at least partially covered with a first layer comprising the first component, the first layer is at least partially covered with a second layer comprising the second component, and the second layer is at least partially covered with a third layer comprising the third component. Typically, in the example mentioned above in which a first N-acylamino acid optionally in salt form is added in a first step and then a second N-acylamino acid optionally in salt form of different nature is added in a second step, then the amino acid in a third step, it is assumed that: either the surface of the pigment is at least partially covered with a layer comprising at least two N-acylamino acids optionally in the form of salts, the two N-acylamino acids being of different natures, and the amino acid, ie the surface of the pigment is at least partially covered with a first layer comprising either the first N-acylamino acid, optionally in salt form, or a mixture of the first and second N-acylamino acid, optionally in the form of salts, and the first layer is at least partially coated with a second layer comprising, respectively, either the amino acid or a mixture of the two x N-acylamino acid optionally in the form of salt and the amino acid, that is to say that the surface of the pigment is at least partially covered with a first layer comprising the first N-acylamino acid, optionally in salt form, the first layer is at least partially covered with a second layer comprising the second N-acylamino acid optionally in salt form, and the second layer is at least partially covered with a third layer comprising the amino acid. By "precipitation" or "deposition" on the pigment of said at least two N-acylamino acids optionally in the form of salts and said amino acid, it is implied that these components precipitate or deposit at least partially on the surface of the pigment (or on the surface of another component covering the surface of the pigment), and therefore none of these components remains completely soluble in the solvent of the medium. Those skilled in the art are able to determine the conditions to be used to carry out the steps a), a2), a4) and a6). The conditions of pH and / or temperature vary in particular according to the nature of the components of the pigment composition. For example, in the embodiment in which a mixture of an N-acylated glutamic acid optionally in salt form and an N-acyl arginine optionally in salt form are added in a first step and then the amino acid selected from cysteine, cystine, methionine, a salt thereof and a mixture thereof in a second step, the process typically comprises the following steps: a1a) solubilization of an N-acylated glutamic acid optionally in the form of salt and an N-acyl arginine optionally in salt form in an aqueous medium of pH between 6 and 11 at a temperature of 40 to 90 ° C, preferably 70 to 85 ° C, a16) addition of at least one pigment to the solution obtained at the end of step a1 a) at a temperature of 40 to 90 ° C, preferably 70 to 85 ° C to obtain a dispersion, a2) cooling of the dispersion, generally to room temperature ( 25 ° C), for a mixture of N-acyl glutamic acid optionally in salt form and N-acyl arginine optionally in the form of salt is deposited at least partially on the surface of the pigment, a3) addition of an aqueous solution of pH greater than 9 (the amino acid being soluble to such pH) of cysteine, cystine, methionine, a salt thereof or a mixture thereof to the cooled dispersion obtained at the end of step a2), a4) adding an acidic aqueous solution to the mixture obtained at the end of step a3), for example hydrochloric acid, until the pH is between 5 and 7, typically 6, whereby the pigment composition precipitates, b) filtration, drying and grinding of the pigment composition. Preferably, in this process, N-acylated glutamic acid is N-cocoyl glutamic acid optionally in salt form, preferably sodium cocoyl glutamate, and N-acyl arginine is N-lauroyl arginine. The solubilization of step a1 a) is then favored because N-cocoyl glutamic acid helps solubilize N-lauroyl arginine which is poorly soluble in aqueous media with a pH of between 6 and 10.

The invention also relates to the pigment compositions obtainable by the processes described above. According to a third subject, the invention relates to the use of the pigment composition or of a pigment composition obtainable by the above-mentioned method for introduction into a cosmetic composition (or for the preparation thereof). preparation of a cosmetic composition), as well as a cosmetic composition comprising the pigment composition.

The cosmetic composition may be aqueous or oily. The cosmetic composition may for example be a hair product (a hair coloring product, a shampoo, a conditioner, etc.), a make-up product (mascara, a foundation, a liner ("eyeliner" in English). ), an eyeshadow or cheek, a lipstick, a lip gloss (lip-gloss), or nail polish) or a care product.

The cosmetic composition may in particular be a semi-permanent hair coloring product, the surface treatment makes it possible to make semipermanent coloration, that is to say that the hair coloring obtained by using this product resists some shampoos (typically 3 to 6 shampoos). By way of comparison, the coloration obtained by using a hair coloring product comprising a pigment in place of the pigment composition according to the invention is typically eliminated in 1 to 2 shampoos maximum. To compare the coloring of the hair, it is possible in particular to carry out colorimetric measurements in the L, a, b system, for example with a Spectro-Guide sphere gloss reference 6834 from BYK-Gardner, and to obtain the values of DE_ (3, L 2 Aa 2 + Ab) 1/2, AL = L 3 shamp L t = 0, - a 3 shamp at t = 0 and Ab = b 3 shamp bt = 0) before shampoo or after three shampoos. The cosmetic composition may be in the form of a monophasic or biphasic lotion, a water-in-oil or an oil-in-water emulsion, a gel, a cream or a powder. According to a fourth subject, the invention relates to a method for preparing a cosmetic composition comprising a step of dispersing a pigment composition as defined above in an aqueous or oily medium.

Advantageously, starting from the pigment composition as a starting product, the process for preparing the cosmetic composition is generally free of grinding step ("grinding" in English). It can therefore be implemented without a mill, which is an advantage because grinding equipment is not necessary and the cost of production of the cosmetic composition is lower.

According to a fifth object, the invention relates to a cosmetic composition that can be obtained by this method. The cosmetic composition typically comprises the pigment composition as defined above and at least one cosmetically acceptable excipient. The invention is illustrated by the following examples.

EXAMPLES Spectro-guide sphere gloss reference 6834 from BYK-Gardner was used to perform colorimetric measurements in the L, a, b system.

The trade names and suppliers of sodium cocoyl glutamate, Lauroyl arginine, Lauroyl lysine and cystine (L-cystine) used in pigment compositions were Plantapon ACG HC from BASF, Friendsafe AL-01 from Ajinomoto, Amihope LL of Ajinomoto and L-cystine of Wacker.

By "ambient temperature" is meant the order of 25 ° C. Example 1: Effects of the components of the pigment composition in a hair coloring product - Preparation of a pigment composition comprising one or two of the components of the pigment composition according to the invention In all the pigment compositions of this example, the pigment is the oxide Unipure Black LC989 black iron. * For Formula 2: pigment composition comprising a pigment, sodium cocoyl glutamate and lauroyl arginine: 1 / Dissolving sodium cocoyl glutamate (15g) and lauroyl arginine (2.5 g) in 243 g of demineralised water at 85-90 ° C, then 2 / Dispersion of 47.5 g of pigment, at 85-90 ° C, stirring for 10 min, then return to ambient temperature, 3 / Filtration, drying, grinding. * For formula 3: pigment composition comprising a pigment and lauroyl lysine: 1 / Dissolving 47.5 g of Pigment in 400 g of demineralized water at room temperature. 2 / Addition to the pigment dispersion of a mixture of 2.5 g of Lauroyl lysine in 247.5 g of a 2.5% aqueous NaOH solution at room temperature with a flow rate of 3 mL / min. Mix for 30 minutes at room temperature. Addition to the mixture obtained a solution of 3N hydrochloric acid (previously obtained by dissolving an aqueous solution of 32% hydrochloric acid) to a pH of 5-7.

Leave stirring for 15 minutes. 3 / filtration, drying, grinding. For formula 4: Pigment composition comprising a pigment and L-cystine The method described above for pigment composition of formula 3 was reproduced by replacing Lauroyl lysine with L-cystine. Preparation of the Hair Coloring Product Four formulas (hair coloring products) having the composition shown in Table 1 were prepared. Formula 1 Formula Formula Formula (Control) 2 3 4 Benzyl Alcohol (%) Propylene Glycol (%) 15 pigment 3 iron oxide black Unipure Black LC989 (%) (control) Pigment composition 3 (pigment / Lauroyl arginine / Sodium cocoyl glutamate) (%) Pigment composition 3 (pigment / Lauroyl lysine) (%) Pigment composition 3 (pigment / cystine ) (%) Polyquaternium-37 (and) dicaprylyl 0.7 carbonate (and) lauryl glucoside (%) Triethanolamine 99% Qs pH = 7.5 - 8 Demineralized water Qs 100 Table 1: Composition of hair coloring product 24 h after the preparation, each formula was applied for 5 minutes on a lock of yak hair and then rinsed with cold water. The colorimetric measurement results of Table 2 were obtained in the L, a, b system.

The value L represents the luminance. When L = 0, it corresponds to the color black. When L = 100, it corresponds to the color white.

A Formula 1 Formula 2 Formula 3 Formula 4 t = 0 comprising 3% comprising 3% including 3`) / 0 comprising 3% of black iron oxide composition composition composition of Unipure Black pigmentary pigmentary pigment LC989 (%) (control ) (pigment / (pigment / Lauroyl (pigment / cystine) Lauroyl arginine / lysine) Sodium cocoyl glutamate) L 36.5 39.5 43.7 31.5 Table 2: Colorimetric measurement results in the L, a, b system formulas 1-4 At t = 0 (that is to say just after rinsing the wick in cold water, without any shampoo and then drying), formula 4 has a lower luminance value L, showing the higher dye power with the pigment treated with cystine and thus its greater affinity for the hair compared to the untreated pigment or treated with one or two Nacylamino acid (s). Six shampoos were then carried out under the following conditions: In a solution at pH = 5.5 of Sodium Lauryl Ether Sulfate with 5% of Active Matter, the wick of yak was soaked for 15 min, it was rubbed for 10 seconds then it was rinsed for 30 seconds in cold water, untangled and dried. The colorimetric measurement results of Table 3 were obtained in the L, a, b system. After 6 Formula 1 Formula 2 Formula 3 Formula 4 shampoos comprising 3`) / 0 comprising 3% comprising 3% comprising 3% of iron oxide of composition composition of black composition Unipure pigmentary pigmentary pigmentary Black LC989 (`) / 0) (pigment / (pigment / (pigment / cystine) (control) Lauroyl Lauroyl lysine) arginine / Sodium cocoyl glutamate) AL 8.3 1.9 9.0 7.5 With AL = L 6 shampoos - L t = 0 Table 3 : Comparison results of colorimetric measurements in the system L, a, b of formulas 1 to 4 just after application to the wick and after 6 shampoos.

Formula 2 has the lowest AL value corresponding to better shampoo resistance compared to other formulas. It is concluded from this example that a surface-treated pigment with cystine will make it possible to obtain a color on the hair after darker application compared to an untreated pigment and that the color obtained with a pigment treated with sodium cocoyl glutamate and lauroyl arginine is more resistant to successive shampoos. The combination of these components should therefore allow to obtain an intense color resistant to several shampoos.

Example 2: Hair coloring product comprising a pigment composition according to the invention Preparation of the pigment composition according to the invention comprising a pigment, lauroyl arginine, sodium cocoyl glutamate and L-cystine a) Mixture of 10 g of Lauroyl arginine and 60 g of sodium cocoyl glutamate in 2430 g of demineralized at 85-90 ° C, stirring for 30 minutes at 85-90 ° C. [3] Addition of 475 g of Pigment (Unipure Triple Black Black Iron Oxide LC990) to the resulting mixture, then a2) Agitation by stopping the heating until the temperature is between 25 and 30 ° C. a3) Addition to the dispersion obtained of a mixture of 15 g of L-cystine and 3.69 g of 30.5% sodium hydroxide in 144.75 g of demineralized water at room temperature. Mixture for 30 minutes at room temperature. b) Addition in 30 minutes to the mixture obtained with a 9.25% hydrochloric acid solution to a pH of the order of 6. Leave stirring for 15 minutes. b3) Filtration, drying, grinding. - Preparation of a hair coloring product Phase Name Supplier Name INCI [EU] Formula 1 (control) Formula 2 commercial (according to the invention) (3/0 W / WA Composition Sensient - 3.00 pigment Cosmetic Tech. Sensient Black 3.00 - Unipure Triple Cosmetic Black LC990 Tech Plantapon ACG BASF Sodium cocoyl glutamate 5.00 HC Natpure Feel-M Eco Sensient Isopropyl palmitate (and) 16.00 Cosmetic isostearyl isostearate (and) Tech octyldodecanol (and) octyldodecyl myristate Natpure Sol Sensient Glycerin (and) sucrose laurate 2.00 Cosmetic (and) sucrose dilaurate (and) Tech sucrose trilaurate (and) sorbitol Covasterol Sensient Glyceryl isostearate, isostearyl 8.00 Cosmetic alcohol, brassica campestris Tech. (rapeseed) sterols, butyrospermum parkii butter & candelilla cera Microcare BNA Thor Benzyl alcohol 0.30 B Pure water --- Aqua up to 100 Natpure Trap TS Sensant Sodium phytate, sodium 0.50 Cosmetic citrate, sodium benzoate Tech Sodium Chloride --- Sodium chloride 1 00 C. Grindsted Beneo Algin 2.00 alginate FD155 Table 4: Composition of the hair coloring product comprising a pigment composition according to the invention A hair dye product comprising a pigment composition according to the invention having the composition indicated in Table 4 was prepared. and following the following procedure: The non-treated Unipure Triple Black LC990 black iron oxide pigment LC990 was dispersed with mechanical stirring (Formula 1 (control)), or the pigment composition according to the invention prepared as described above ( formula 2), in the oily phase A at room temperature (25 ° C.). The aqueous phase B was then added to obtain an emulsion. Phase C was dispersed and stirring was continued until a homogeneous gel cream was obtained. 24 hours after manufacture, the formula was applied for 5 minutes on a lock of yak hair and then rinsed with cold water. The colorimetric measurement results shown in Table 5 were obtained in the L, a, b system.

A Formula 1 Formula 2 comprising 3% pigment composition (pigment / Lauroyl arginine / sodium cocoyl glutamate / L-cystine) (according to the invention) t = 0 comprising 3% black iron oxide Unipure Triple Black LC990 (%) (control) L 52.76 30.49 to 0.38 1.36 b 4.2 3.61 Table 5: Colorimetric measurement results shown in Table 5 in the L, a, b system of a coloring product capillary comprising a pigment composition according to the invention At t = 0, the formula 2 has a luminance value L lower than the formula 1, showing the higher coloring power with the coloring product comprising the pigment composition according to the invention and its greater affinity for the hair compared to that comprising the untreated pigment.

3 shampoos were then carried out under the following conditions: In a solution of pH 5,5 of 5% Sodium Lauryl Ether Sulfate of Active Matter, the wick of yak was soaked for 15 min, it was rubbed for 10 seconds then it was rinsed for 30 seconds in cold water, untangled and dried. The colorimetric measurement results of Table 6 were obtained in the L, a, b system: After 3 Formula 1 Formula 2 comprising 3% shampoos comprising 3% black iron oxide pigment composition Triple Black Unipure LC990 (%) ( pigment / Lauroyl arginine / (control) Sodium cocoyl glutamate / L-cystine) (according to the invention) L 69.29 51.26 a -0.20 1.31 b 7.42 5.74 3.E 20.88 16.85 With 3.E = (Ar + ± Ab) 1/2 AL _ = L 3 field L t = 0, Da = a 3 shamp - t = 0 and = b 3shamp - bt = 0 Table 6: results comparison of colorimetric measurements in the system L, a, b of formulas 1 and 2 just after application to the wick and after 3 shampoos. The lowest value of 3.E of formula 2 shows that the wick on which the hair coloring product comprising a pigment composition according to the invention has been applied is more resistant to shampooing than that on which the hair coloring product has been applied. comprising an untreated pigment. Example 3: Foundation (water-in-oil) comprising a pigment composition according to the invention - Preparation of a pigment composition Three pigment compositions according to the invention were prepared by reproducing the process of Example 2 but replacing the pigment black iron oxide Unipure Triple Black LC990: either with a pigment Unipure Yellow LC182, or with a pigment Unipure Red LC381, or with a pigment Unipure White LC987.25 A pigment composition was then prepared by mixing the three pigment compositions obtained and the pigment composition of Example 2 comprising Unipure Triple Black pigment LC990 in the following proportions: 1.25% of pigment composition comprising a pigment Unipure Yellow LC182, sodium cocoyl glutamate, cystine and lauroyl arginine, , 45% of pigment composition comprising a pigment Unipure Red LC381, sodium cocoyl glutamate, cystine and lauroyl arginine, 8.05% of composition pigment ion comprising a pigment Unipure White LC987, sodium cocoyl glutamate, cystine and lauroyl arginine, 0.25% pigment composition comprising a pigment Unipure Triple Black LC990, sodium cocoyl glutamate, cystine and lauroyl arginine. This pigment composition comprising four pigments was used to prepare a foundation. - Preparation of the foundation Phase Name Supplier INCI name% W / W commercial A Silamer HC Sensient Triethylhexanoin // Cetyl PEG / PPG- 6.00 Cosmetic 10/1 dimethicone / polyglyceryl-2- Tech. isostearate / hexyl laurate DC 2502 Dow Corning Cetyl dimethicone 1.90 cosmetic fluid Synthetic Baerlocher Synthetic beeswax 0.65 beeswax Castor oil Baerlocher Hydrogenated castor oil 0.30 hydrogenated Dow Corning Croda Phenyltrimethicone 12.50 556 Fluid Composition Sensient Iran oxide / sodium cocoyl glutamate / 10.00 pigmentary Cosmetic cystine / lauroyl arginine Tech. Dow Corning Dow Corning Cyclopentasiloxane 9.20 245 C Pure water --- Aqua up to 100 NaCl --- Sodium chloride 0.60 Propylene --- Propylene glycol 6.00 glycol Microcare PM3 Thor Phenoxyethanol, methylparaben, 0.30 ethylparaben, propylparaben Submica M Mica Sensient 5.05 Cosmetic Tech. Table 7: Composition of the foundation (water in oil) comprising a pigment composition according to the invention A foundation having the composition indicated in Table 7 was prepared according to one or other of the following 2 operating modes Procedure 1: Pigmenting of the pigments in part of the phase A with 3 passes with the three-cylinder with an EXAKT 50 type apparatus (Exakt) (grinding of the pigment) and then adding the remainder of the phase A.

Procedure 2: dispersion of the pigments under strong mechanical agitation in the whole of phase A. The rest of the procedure was identical for both formulas. Then add phase B and homogenization.

Add phase C to obtain an emulsion and after complete homogenization, disperse phase D. Stirring was maintained until a homogeneous emulsion was obtained. The colorimetric measurement results shown in Table 8 were obtained in system L, a, b: Procedure 1 Procedure 2 L 55.59 56.45 A 11.27 10.57 b 18.78 18.65 AE 1,116 AE = (AL2 + Aa2 + Ab2) 1/2 Table 8: results of colorimetric measurements in the L, a, b system of the formulas obtained according to the procedure 1 or 2. The low value of AE shows that the two formulas are considered to have close (identical) colors. The pigment composition according to the invention is therefore easy to disperse in the cosmetic composition and the milling step by repeated passages with the three-cylinder is not necessary. EXAMPLE 4 Mascara (oil-in-water emulsion) comprising a pigment composition according to the invention The pigment composition used is the same as that of Example 2. Phase Name Supplier INCI Name Formula Formula Commercial 2 (according to (control) the invention) (3/0 W / VV A Base RW 135 Sensant Synthetic beeswax / Copernicia 15.00 Cosmetic cerifera cera [Copernicia cerifera Tech. (carnauba) wax] / Stearic acid / Ceteareth-25 / PEG-2 stearate / Paraffinum liquidum [Orester oil] / Hydrogenated coconut oil / Cetyl alcohol B Covacryl MV60 Dow Sodium polyacrylate 0.50 Corning Microcare PM3 Thor Phenoxyethanol / Methyl paraben / 0.30 Ethyl paraben / Propyl paraben Triethanolamine Triethanolamine 1.00 99% Pure water Water 47, 45 C Sensant Pigment 0177499 13.00 - (Unipure Triple Cosmetic Black LC990 Tech Composition 0177499 / sodium cocoyl glutamate / - 13.00 pigmentary cystine / lauroyl arginine D Crodamol Croda Triethylhexanoin 9.50 GTEH E Covabead V20 Sensient Polymethylmethacrylate 4 , 00 Cosmetic Tech. Fiberlon 54 Sensient Nylon-66 / titanium dioxide 0,25 Cosmetic Tech. Covacryl MT10 Sensient Acrylates / Ethylhexyl Acrylate 9.00 Cosmetic Copolymer Tech. Table 9: Composition of the mascara (oil in water) comprising a pigment composition according to the invention. 2 mascaras having the composition shown in Table 9 were prepared according to the following procedure: Heat phase A at 75 ° C with slow stirring.

Prepare phase B separately: Introduce water, triethanolamine and Microcare PM3 and homogenize. Heat to 75 ° C and disperse the Covacryl MV60. Add phase B to phase A with stirring at 75 ° C to make the emulsion and then cool to room temperature (25 ° C). Emphasize phase C in part of the emulsion and pass 3 times to the three-cylinder. Add the remaining emulsion and homogenize. Slowly add phase D and homogenize. Disperse phase E and homogenize then phase F and homogenize. The mascara comprising an untreated pigment (formula 1) and the mascara comprising the pigment composition according to the invention (formula 2) are both easy to apply, but that comprising the pigment composition according to the invention (formula 2) shows a superior water resistance (long lasting effect).

Claims (1)

1. Pigmentary composition in the form of a powder comprising: at least one pigment, at least two N-acylamino acids, optionally in the form of salts, the two N-acylamino acids being of different natures, and an amino acid chosen from cysteine, cystine, methionine, a salt thereof and a mixture thereof. 2. Pigmentary composition in powder form according to claim 1, in which the two N-acylamino acids independently satisfy the following formula (I): R1- (CO) -NR3-CHR2- (CO) -O ( M), /, (I), wherein: R1 represents a linear, branched or cyclic, typically linear, alkyl or alkenyl group having from 8 to 22 carbon atoms, R2 is a group selected from H, Me, (CH2 ) 3-NH- (CNH) -NH2, CH2- (CO) -NH2, CH2- (CO) -OH, CH2SH, (CH2) 2- (CO) -NH2, (CH2) 2- (CO) -OH , CH2-imidazolyl, CHMe-CH2-CH3, CH2-CHMe2, (CH2) 4 -NH2, (CH2) 2-S-Me, CH2-phenyl, CH2-pyrrolidinyl, CH2-OH, CH (OH) -Me, CH 2 -indolyl, CH 2 -p-hydroxyphenyl and CHMe 2, R 3 represents H, or R 3 and R 2 together represent a divalent group - (CH 2) 3, M is chosen from H, Na, K, Ba, Zn, Ca, Mg , Fe, Zr, Co, Al, Ti, NH4 and an alkanolamine onium, such as monoethanolamine, diethanolamine, triethanolamine, 2-amino-2-methyl-propanol, 2-amino-2-methyl- 1,3-propanediol and triisopropano lamine, m is 1 when M is H or m is the valency of the cation M. 3. A pigmentary composition in powder form according to claim 2, wherein one of the N-acylamino acids is an N-acylated glutamic acid, optionally in the form of a salt, in particular an N-cocoyl glutamic acid, optionally in salt form, in particular sodium cocoyl glutamate. 4. Pigmentary composition in powder form according to claim 2 or 3, wherein one of the N-acylamino acids is an N-acyl arginine optionally in salt form, especially N-lauroyl arginine. 5. Powdered pigment composition according to claim 3 or 4, wherein the two N-acylamino acids are sodium cocoyl glutamate and Nlauroyl arginine. 6. A pigment composition in powder form according to any one of claims 1 to 5, wherein the amino acid is cystine or a salt thereof, especially L-cystine. 7. Pigmentary composition in powder form according to any one of claims 1 to 6, wherein the pigment is: an inorganic pigment, especially selected from titanium dioxide, zinc dioxide, zirconium oxides or cerium as well as oxides of iron or chromium, manganese violet, ultramarine blue, chromium hydrate and ferric blue, and mixtures thereof, an organic pigment, chosen in particular from carbon black, such as D & C black No. 2, red organic pigments, such as D & C Red No. 6, No. 7, No. 21, No. 27, No. 28, No. 30, No. 33, No. 36, No. 40 , and cochineal Carmine, blue organic pigments, such as copper phthalocyanine and FD & C Blue No. 1 lacquer, and yellow organic pigments, such as D & C Yellow No. 10, FD & C Yellow No. 5 Lacquer and 6, and mixtures thereof, or a mineral filler, especially chosen from talc, kaolin, alumina, silica, and nacres such as borosilicates or mica, natur or synthetic, and optionally coated with titanium oxide, iron oxide, chromium oxide or a mixture of these oxides. 8. A process for preparing a pigment composition according to any one of claims 1 to 7, comprising the following steps: a) mixing in a solvent: at least one pigment, at least two N-acylamino acids optionally in the form of salts, the two N-acylamino acids being of different natures, and an amino acid selected from cysteine, cystine, methionine, a salt thereof and a mixture thereof, and deposition or precipitation on the pigment of said at least two Nacylamino acids optionally in salt form and said amino acid, b) filtering the pigment composition, or evaporation of the solvent, drying and grinding to obtain the pigment composition in powder form. 9. A preparation process according to claim 8, wherein step a) comprises the following steps: a1) mixing in a solvent at least one pigment and at least two Nacylamino acids optionally in the form of salts, a2) adapting the temperature and / or pH conditions so that the at least two N-acylamino acids optionally in the form of salts are deposited at least partially on the surface of the pigment, a3) adding to the mixture obtained at the end of the step a2) of the amino acid, optionally in a solvent of the same or different nature of the solvent of step a1), a4) adaptation of the temperature and / or pH conditions so that the amino acid is deposited at least partially on the surface of the pigment and / or on the surface of the at least two N-acylamino acids optionally in the form of salts. 10. A pigment composition obtainable by the process according to claim 9. 11. Cosmetic composition comprising a pigment composition according to any one of claims 1 to 8 and 10. 12. Cosmetic composition according to claim 11, being a semi-permanent hair coloring product.