NATURAL INSTANT COLORS AND METHODS FOR THEIR PRODUCER

Description

[0001] The invention relates to the field of dyes, particularly natural dyes. More specifically, the invention concerns coloring products obtained by reacting natural extracts containing dye precursors (coloring substances and / or pigments), their preparation, packaging, and application. These coloring products can be used in the cosmetic field, particularly for hair dyeing and skin tattooing, as well as in the pharmaceutical / dermocosmetic, food, veterinary, and textile dyeing sectors. These dyes can be in the form of instant powders or ready-to-use preparations. STATE OF TECHNIQUE Hair colorations

[0002] There are two main methods for coloring human hair: oxidative colorings, also called "permanent," and direct colorings, also called "semi-permanent."

[0003] In both cases, the active components are molecules obtained through synthesis.

[0004] Oxidative hair coloring involves the application of one or more oxidative bases located within the hair fibers, sometimes in combination with couplers. Current techniques involve activating the coloring precursors using enzymatic catalysts (polyphenol oxidases) or chemical oxidants (hydrogen peroxide). However, the use of these compounds poses toxicological risks. Recently, the health and environmental risks associated with "chemical" hair coloring have led the European Union to ban a whole range of dyes.

[0005] Direct coloring involves the application of colored molecules that have an affinity for hair fibers and keratins (hair, eyebrows, body hair). The molecules used remain mostly on the surface and penetrate only slightly into the fiber.

[0006] The main advantage of this type of coloring is to limit the degradation of the fibers and the risks of intolerance.

[0007] Plant extracts with coloring properties are used in this second category; they employ compounds with varying degrees of affinity for hair fibers. The methods used in plant-based hair dyes can be quite diverse. Plant capillary dyes

[0008] There is a growing consumer demand for cosmetic, textile, and food colorants derived from natural substances, particularly to avoid the toxicity and risks associated with synthetic molecules. Furthermore, the market for artificial colorants is declining while that of natural colorants is growing by approximately 10% per year.

[0009] The use of plants as coloring agents is found in a large number of traditional knowledge systems. For example, henna ( Lawsonia in the ) is among the most widely used dye plants.

[0010] Traditional plant-based hair coloring uses a simple composition: extracts of dye plants and pigments (henna, madder, chamomile, indigo, etc.) ground and mixed with water. Unlike chemical (oxidative) coloring, which opens the hair cuticle, lightens the melanin, and then colors it through a chemical reaction, plant-based dyes do not penetrate the hair fibers. In fact, the dyes contained in the plants adhere to the hair fiber and do not alter the hair's natural melanin. It is a tone-on-tone coloring, which cannot lighten the hair. Its effect is semi-permanent (2 to 6 weeks). Despite their short duration, the advantages of natural dyes are numerous: The color result is very natural, without a "helmet" effect, because the pigments blend with the base hair color. As a result, regrowth is less noticeable.Allergies are also less frequent than with the chemical technique. Plants with dye power

[0011] For natural dyes (plant, mineral, or animal) to be effective, the material to be colored (keratin fibers from hair, textile fibers, or others) is generally saturated with a mordant, which can be incorporated into the dye solution. Mordants are compounds that adhere to the fibers, allowing the dye to adhere. The main mordants are based on chromium, copper salts, tin, iron sulfate, alum, and oxalic acid. This technique has been used since antiquity for applying dyes to plant fibers (wool, silk, linen).

[0012] Various plants can be used for coloring hair fibers such as henna, indigo, walnut husk, madder, annatto, carmine, etc.

[0013] Henna ( Lawsonia inermis L., L. alba Henna has been used for five millennia as a coloring agent for hair and body (Food and Chemical Toxicology 42:517-543, 2004). A poultice of crushed henna leaves produces a red, orange, or copper color, depending on the hair color. The main coloring constituent of henna is lawsone (2-hydroxy-1,4-naftoquinone) (CAS 84.988-66-9), which occurs naturally at up to 2% of the crude extract and in the form of hennoside (glucoside).

[0014] In the case of henna, enzymatic hydrolysis, facilitated by the formulations, leads to the cleavage of the hennoside, releasing the lawsone molecule, an active but unstable dye. Henna powder must remain in a slightly acidic aqueous solution for 6 to 24 hours to release the lawsone and allow its use as a dye. Furthermore, the pH of the dye solution influences the color result. Thus, at a pH below 6, the predominant color is red. Above 6, the intensity decreases, and yellow becomes predominant.

[0015] Coloring powders are often prepared as a poultice. Henna powders (green in color) are generally ground into a very fine granules which, when mixed with water, form the poultice applied directly to the hair. Pure henna never produces a black color, but rather a coppery-orange one. However, certain characteristics inherent to the raw extracts or coloring compounds may not be compatible with other dyes or pigments.

[0016] The increasing use of henna body art can also pose a health risk due to the synthetic chemicals fraudulently used to shorten the skin's tanning time or to enhance or alter colors (Contact Dermatitis 55:26-29, 2006). Indeed, adulterated henna powders intended for hair coloring or temporary tattoos very often escape standard controls, and toxic ingredients may be added. Dark henna (black or mahogany) may contain para-phenylenediamine (PPD), a synthetic dye, or, in the worst cases, lead acetate, which is strictly prohibited in the European Union. The consequences can be serious (for example, allergic reactions to henna from tattoos adulterated with PPD).Thus, some products sold under the name "henna" contain other dyes leading to unexpected results and sometimes toxicity due to integrated compounds. Examples of traditional preparations: poultices

[0017] Formulation based on Henna: Coloring processes using henna are delicate to implement. A traditional henna-based formulation is prepared from 30 to 100g of ground leaf powder (35 to 80 mesh) dissolved in 300 mL of boiling water. After cooling, the poultice (or paste containing soluble and insoluble materials) is applied directly to the hair for 3 to 24 hours. The hair is covered with plastic or fabric to avoid staining clothing. The poor consistency of this poultice generally leads to uneven hair penetration and an unsatisfactory result.

[0018] Baseline FormulationIndigo: Poultices prepared from crushed indigo leaves ( Isactis tinctoria The fibers are first fermented in hot water to release the mauve-colored indigo. This poultice (diluted or undiluted) is then applied directly to the keratin fibers. The poor consistency of the mixture prevents adequate dye penetration, resulting in uneven coloring.

[0019] Tattoo formulation (body art): For body tattooing, dried and powdered leaves are mixed with a slightly acidic solution (lemon or orange juice, vinegar) to create a paste that is applied directly to the body using various tools. Several factors lead to colors that can range from orange to auburn.

[0020] It should be noted that henna extract (Lawsonia Inermis) is not only a coloring agent, but it also provides numerous health benefits. The plant contains, in particular, terpenoids (with antimicrobial effects), sterols, aliphatic derivatives, xanthones (yellow pigments with antioxidant and anti-inflammatory properties), tannins, coumarins, flavonoids, fatty acids, amino acids, essential oils, and other constituents. The Scientific Committee on Consumer Safety (SCCS) has concluded that henna is safe to use ( Lawsonia in particular, avec (contains 1.4% lawsone) as a colorant in the usual doses (100 g of henna / 300 mL of H2O or 330 mg / mL (COLIPA No. C169, 19.09.2013).

[0021] Henna thus possesses antioxidant, antimicrobial, antiviral, antiparasitic, antifungal, anti-inflammatory, antidiabetic, anticancer, hepatoprotective and immunomodulatory properties. Natural Naphthoquinones

[0022] Natural naphthoquinones ( lawsone, juglone, plumbagine, lapachone ) have strong fungicidal and bactericidal activity (Nat Prod Res. 2014;28(11): 835-7; J Agric Food Chem. 2012 Dec 12; Nat Prod Res. 2012;26(12):1119-24; Phytother Res. 2001 Dec;15(8):676-80). These compounds exhibit protective activity on the skin. For example, the bactericidal, fungicidal, and cytostatic properties of lawsone have been demonstrated (Chelossi, E. & Faimali, M. Science of The Total Environment 356, 1-10, 2006; Kapadia, JG et al. Anti-Cancer Agents in Medicinal Chemistry - Anti-Cancer Agents) 13, 1500-1507, 2013; Yusuf, M. et al. Journal of Cleaner Production 27, 42-50, 2012.

[0023] The results of coloring with these poultices are difficult to control; the result varies depending on the concentrations and quality of the raw materials (henna, indigo, etc.) as well as the nature of the fibers to be colored. DISADVANTAGES OF THE STATE OF TECHNIQUE

[0024] Although many natural dye-based dyes are described, for example in the document Forestiert et al., "Henne. Absorption of lawsone by the horse, Int. J. of Cosmetic Sci., Kluver Academic Publishers, Dordrecht, NL, vol. 4, January 1, 1982 (1982-01-01), pages 153-174, and / or available commercially, these have some drawbacks.

[0025] Firstly, it is observed that natural dyes (plants, vegetables, fruits, citrus fruits, minerals, algae) are underutilized due to the technical difficulties encountered in obtaining effective dyes: Some active ingredients are unstable in the presence of light, heat, temperature, and / or pH variations. Preparing poultices from raw plant extracts results in uneven consistencies, due in part to the insolubility of some of the extracted materials. This can lead to reduced effectiveness due to uneven distribution on the hair, or even to uneven hair coloring. Color retention in hair can be reduced due to the instability of the dye in light or heat, or the lack of affinity of certain natural dyes for keratin fibers.

[0026] Despite the diversity of natural products and the color potential offered by plants, currently available plant-based hair dyes only allow for tone-on-tone or highlighting results. This is due to several factors intrinsic to the raw materials or the nature of the active ingredients, including: Concentration of active molecules : The intensity of the colors obtained with natural dyes is limited due to the low level of active constituents in the crude extract; for example, henna generally contains 0.5 to 1.5% lawsone. Partial solubility of extracts: The plant materials (leaves, roots, bark) are often ground and then made into poultices before being applied to the hair. The insolubility of some of the extract makes it difficult to apply to the hair. In addition to uneven distribution, it can leave an unpleasant feeling to the touch. The insoluble residue limits the conditioning effect. Non-homogeneous preparation and resting time: Preparing the extract takes 30 minutes to 1 hour, plus the time needed for the extraction (hydrolysis) of the active constituents by the enzymes present (6 to 24 hours), the time to prepare the poultice, and the waiting time after application to the hair (30 minutes to 2 hours). In total, traditional plant-based hair coloring takes longer than conventional chemical dyes. Stability of active compounds and shelf life: Extraction techniques combining excessively acidic pH and high temperature promote hydrolysis. These aggressive techniques break down coloring substances, altering their coloring capacity and degree of assimilation, not to mention the partial or total destruction of certain vitamins, components of interest for coloring action.

[0027] Faced with these difficulties in use, consumers are looking for natural products, more respectful of health and nature, but effective and with a satisfactory aesthetic result.

[0028] This growing consumer demand for natural products has led to the emergence of pseudo-natural dyes. Misleading labels create confusion among consumers by passing off products using chemical coloring principles as natural dyes: "Plant-based dye," "Color-care with dye plants," "With lychee extract," "Enriched with aloe vera," or even "With ingredients from organic farming." Generally, these claims refer to chemical dyes that are "enriched" with a number of plant-based components without any ingredient that actually acts as a dye. These are essentially dyes with active ingredients (dyes).

[0029] There is therefore a technical gap in meeting consumer demand for more stable and effective natural colorants. This situation results, on the one hand, in a need for manufacturers to have access to stable and effective natural active ingredients for use as colorants, and on the other hand, in a need for consumers to have access to truly natural products that are safe for their health and, at the same time, effective. ADVANTAGES OF THE INVENTION

[0030] The invention implements a process for preparing instant, water-soluble, natural coloring products from colorless organic precursors that form molecular or complex associations with pigments or coloring molecules. This process involves a reaction using direct coloring precursors and copigments found in plants or extracts of different species, along with a polyfunctional natural catalyst. The presence of polyfunctional molecules, such as amino acids, appears to induce reactions between these molecules, leading to the formation of a more stable dye and original colors in the resulting solution.

[0031] The present invention proposes a new type of colorant, which can be 100% natural, obtained by a reaction between colorant precursors or other colorants and copigments in the presence of polyfunctional catalysts such as amino acids, as well as their use, particularly for hair coloring and skin tattooing, but also in the food, pharmaceutical, veterinary, and textile dyeing sectors. These colorants can be in various ready-to-use or dissolving forms, such as water-soluble instant powders. The invention also relates to the process for preparing coloring products, which can be composed solely of natural ingredients. Preparing colorant in the form of a water-soluble lyophilized powder allows for greater preservation and facilitates the on-site preparation of ready-to-apply masks.

[0032] Thus, the invention addresses the drawbacks of the prior art for the following reasons: a. The process according to the invention is applied to dye precursors and copigments in the presence of natural catalysts (e.g., amino acids, sulfur derivatives of garlic), which allows for the potentiation of the coloring action of the plants and their mixture, in particular by enriching the active compounds (dye precursors and their derivatives); b. The copigmentation dyes obtained according to the invention have an improved affinity for keratin fibers, which allows for more intense coloring; c. The stability of the dyes extracted from the plants is increased (more stable color), particularly when the coloring products are in lyophilized form (alternatively, as instant coloring powder obtained via the spray-drying technique); d.The natural coloring products offered are ready-to-use in the form of instant natural colorants usable in various fields such as cosmetics, food processing, veterinary medicine and textile coloring or as a pharmaceutical adjuvant. DETAILED DESCRIPTION OF THE INVENTION

[0033] The inventors propose new instant and water-soluble coloring products obtained by reaction between a precursor of natural colorings of various origins (compound I) and a copigment (compound II) with a polyfunctional natural catalyst, in particular an amino acid (compound III).

[0034] A first object of the invention relates to a process for preparing an instant, water-soluble dye consisting of reacting at least one compound I and one compound II with at least one compound III, said compounds I, II and III being chemocompatible with each other, in a weakly acidic medium having a pH between 3.5 and 6.5, at a temperature between 30°C and 55°C (exceptionally up to 70°C), for a duration between 10 and 45 minutes, in which: Compound I is a colorant precursor, compound II is a co-pigment, compounds I and II being selected from naphthoquinones, quinones, antraquinones, indoles, bis-indoles, xanthones, flavonoids, pyranoanthocyanins, crommenes, iridoids, preridins, isoquinolines, phanoxalins, phenazines, polyenes, carotenoids and chalcones; compound III is a polyfunctional natural catalyst selected from tannins, aliphatic acids, aromatic acids and phenolic acids, organic acids, carbonates, alkaloids, amino acids and alkaloids.

[0035] For the purposes of this invention, "dye precursor" means a direct dye or pigment.

[0036] Preferably, the process for preparing an instant and water-soluble dye according to the invention consists of reacting the water-soluble parts of plants rich in precursors of chromophore dyes and / or auxochrome groups as sources of compounds I, and / or II and / or III.

[0037] In a particular embodiment of the process, the reaction temperature is between 30°C and 55°C, preferably between 40°C and 55°C, and even more preferably between 45°C and 50°C, although this may vary depending on the nature and stability of the compounds being mixed. The temperature may exceptionally reach up to 70°C.

[0038] In another particular embodiment of the process, the reaction time is between 10 and 30 minutes, preferably between 10 and 20 minutes, and most preferably between 10 and 15 minutes. It is also possible to carry out longer reactions depending on the nature of the compounds being mixed.

[0039] In another particular embodiment of the process, the pH of the reaction is between 4 and 5.

[0040] The colouring product obtained by reaction is cooled under stirring to room temperature (typically between 20°C and 25°C).

[0041] In another embodiment, the process further includes a pre-reaction step, consisting of extracting compound(s) I from plant extracts, as described below.

[0042] In another embodiment, compound III is a thioamino acid, for example cysteine, methionine or glutathione.

[0043] In another embodiment, the process further includes a step of freezing the coloring products obtained at the end of the reaction.

[0044] In another embodiment, the process further includes a freeze-drying or spray-drying step of the coloring agents to obtain an instant hydrophilic powder. Freeze-drying can be carried out either directly after the reaction or after freezing and grinding. Spray-drying is performed using only the liquid solution resulting from the reaction.

[0045] The goal is to facilitate the interaction of these compounds under mild conditions (pH, temperature) and high concentration. In addition to facilitating contact between plants with different compositions, the catalysts (e.g., polyfunctional amino acids) provide anchoring sites for these entities and contribute to their attachment to the final support, the keratin fibers.

[0046] Copigmentation is a natural phenomenon that occurs in solution, during which pigments and other colorless organic molecules form molecular associations or complexes with pigments or molecules that possess coloring power. Copigments have an effect on increasing color intensity and stabilizing coloring molecules (Markovic et al., 2000).

[0047] The originality of this process lies in enhancing the stability and coloring power of natural dyes through their reaction with copigments in the presence of a multifunctional catalyst (natural or synthetic). The inventors have demonstrated that the resulting natural dyes are more stable and longer-lasting on keratin fibers (hair, eyelashes, eyebrows, body hair) and skin proteins, among other things. The resulting coloring products, called "copigmentation dyes," correspond to the intermolecular, intramolecular, or addition reactions that occur when dye precursors are mixed with copigments or plant extracts under specific conditions (temperature, pH, time), in the presence of a multifunctional catalyst. The aim is to obtain colors more resistant to variations in pH, temperature, and solvents, as well as new colors resulting from multiple combinations.

[0048] The precursors of dyes and pigments are selected in order to find a suitable application according to the desired objectives.

[0049] In the process of the invention, the direct dye precursors present in plant extracts (madder, indigo, henna, etc.) are first released from their heteroside form (aglycone + carbohydrates) by enzymes present in the crude plant extract. The extraction of the copigments from plants rich in these substances, as well as auxiliary copigments (chestnut, walnut, guarana), is carried out in a hydroalcoholic medium.

[0050] It is also possible to use dyes and / or copigments already extracted, or even purified, and available commercially to carry out a copigmentation reaction according to the invention.

[0051] Dye precursors are chosen from extracts of plants, fruits, berries, grains, citrus fruits, vegetables, and mixtures thereof. These raw materials contain free or derived direct coloring active ingredients (glycosides, salts, etc.) with varied molecular structures.

[0052] Compounds I of the invention correspond to colorant precursors, compounds II correspond to copigments and compounds III correspond to polyfunctional catalysts (also called "polyfunctional copigments" or "auxiliary copigments").

[0053] Direct colorants, pigments and natural co-pigments of traditional use can be chosen from the molecular families (colorants or pigments) described below or their derivatives (quinones, antraquinones, naphthoquinones, indoles, anthocyanins, xanthones, flavonoids, cromenes, pteridines, isoquinolines, phenothiazines, iridoids, polyenes, chalcones, as well as shikimates, terpenes, steroids, polyacetates, amino acids etc...).

[0054] Direct dyes, pigments, and co-pigments are obtained through aqueous (or hydroalcoholic) extraction from plants, leaves, or other plant parts. Several plants or other natural materials with direct coloring properties can be used or modified to obtain compounds I or II. The materials are ground, macerated, or atomized prior to aqueous or hydroalcoholic extraction. The quantity of the dye precursor or direct coloring molecules in the initial dry extract must be sufficient to achieve visible color. This quantity must be adjusted according to the precursor and the desired color intensity.

[0055] From a structural point of view, an organic direct dye molecule has a specific configuration necessary to produce color. Several conditions must be met for the molecule to exhibit the color: It must bear chromophore groups and be highly conjugated (alternating numerous double and single bonds); it must bear auxochrome groups which intensify the initial color produced.

[0056] Thus, a direct dye necessarily contains two types of groups: chromophore groups and auxochrome groups.

[0057] Copigments are not coloring agents in themselves. They are colored or colorless molecules, present in the plant, mineral, or animal kingdoms, distinct from molecules with coloring power. Compared to a direct dye, a copigment comprises either chromophore groups or auxochrome groups.

[0058] A wide variety of plants have constituents (families of molecules) with similar chemical structures and properties, including copigments such as flavonoids (flavones, flavonols, flavanones, and flavanols) and other polyphenols, alkaloids, amino acids, including thio-amino acids, organic acids (i.e., hydroxycinnamic acids and hydroxybenzoic acids), tannins, etc.

[0059] Amino acids, for example, are considered to be low-toxicity molecules and they contain at least carboxyl and amine functional groups, and some have sulfur, guanine thiol or phenolic hydroxyl groups.

[0060] The interaction between dye precursors and copigments results in a more intense final color solution. They can, for example, be added to the aqueous or hydroalcoholic extract of the coloring compound or prepared separately for mixing with this coloring compound in a second phase. However, simply mixing dye precursors and copigments does not produce homogeneous coloring of the substrates (e.g., hair fibers, fabrics). The invention overcomes this drawback by proposing the addition of a natural catalyst to the reaction between dye precursors and copigments.

[0061] Compounds I and II are selected from natural colorant precursors and co-pigments as described below. These pigments can be obtained from natural sources, whether plant, animal, or mineral. However, synthetic colorants may also be considered in this category.

[0062] The following natural organic dyes are classified according to their chemical structure. At the molecular level, a specific structural configuration of the molecule is necessary to produce color. The groups of atoms responsible for the color of dyes are called chromophores. These chromophores can contain azo groups (-N=N-), carbonyl groups (-C=O), nitrate groups (-NO2+), nitrosate groups (-N=O), alkene groups (-C=C-), etc. Numerous double bonds are required for the substance to be colored.

[0063] Groups called "auxochrome groups" allow dyes to be fixed to fibers and can modify the color of the dye. Auxochrome groups can be acidic (-COOH, SO3H, -OH) or basic (NH2, NHR, NR2).

[0064] The molecular families and plants containing direct dyes, pigments and copigments used as active substances in the context of the present invention are presented below: Compounds I and II: Direct dyes and pigments, and copigments

[0065] NAPHTOQUINONES AND DERIVATIVES: Walnut or walnut husk ( Juglans cinerea, J. regia, J. nigra ): juglone, juglandin; Henna ( Lawsonia inermis, Lawsonia alba ) : lawsone; Dyer's alkanet ( Alkanna tinctorial , Lithosphermum tinctorium (VAH L.): alkannine; Tabebuia and Tecoma ( Tabebuia sp, T. Avellaneda): lapachol, beta-lapachone; Sundew ( Drosera rotundifolia, D. intermedia , D. anglica ) : plumbagone; Canadian Shepherdie (Shepherdia canadensis) : chimaphilin, balsam ( Impatiens balsamina ) . QUINONE, ANTRAQUINONE AND DERIVATIVES: Madder ( Rubia tinctorum, R. peregrina, R. cordifolia ) , The roots contain up to 19 colorants: alizarin, purpurin, xanthopurpurin, rubiadin, ruberythrinic acid; Rhubarb roots ( Rheum rhaponticum, R. palmatum, R . officinalis): Chrysophanic acid; Bedstraw, or White Bedstraw, roots (Galium mollugo, G. odoratum, G. verum) alizarin; Aloe (Aloe vera) :Aloin A and B, aloesone; Lacca (Coccus laccae): laccic acid A, B, C and D; Carmine Red (Cochineal of Cactus cactus Or Dactylopius coccus ) ; (used with or without mordant): carminic acid, kermesic acid, flavokermesic acid; St. John's wort ( Hypericum perforatum ): hyperofrin, hypericin, and polycyclic quinones. INDOLES, BIS-INDOLOID, AND DERIVATIVES: Indigo, leaves (Indigofera tinctoria, Indigo suffraticosa, I. articulata, I. arrecta, I. gerardiana, I. argenta, I. indica, I. longiracemosa, Persicaria tinctoria ) : indigo ; Pastel des teinturiers ou Jaune d'or (Isactis tinctoria): cis- and trans-indigo, indigorubine; Polygonum ( Persicaria tinctoria Gardena blue ( Clerodendrum trichotomium ) : phycocyanolibin, guaiazulene, trichotomine; Beetroot ( Beetroot ) : betanins, betanidine, isobetanidine, vulgaxanthins (beetroot red is very unstable); Plant melanins: allomelanins and phaeomelanins. XANTONES, FLAVONOIDS, ANTHOCYANS AND DERIVATIVES: Extracts of rose, tea and fruits: apple, grape, blackberry, acai: pelargonidin (Pelargonium), cyanidin (roses, cranberries), malvidin, paeonidin, delphinidin ( Viola tricolor) , catequina ( Acacia catechu ) ; Chamomile flowers ( Matricaria recutila, M. chamomilla ): azulene, apigenin; Buckthorn, bark (Rhamnus frangula, Frangula alnus): flavonoids, tannins; Açaí, fruits ( Euterpe oleracea ): Antocianins, polifenois and tannins; Eyelet (Carnation ) : cyanidin, pelargonidin; Raisin rouge (Vitis vinifera): cyanidin and other polyphenols (tannins, polyphenolic seeds); Grape marc: lignan (lyoniresinol) and other polymers; Sophora, flower buds ( Japanese Sophora ) : Rutoside; Oak bark, tea, walnuts, red onions: quecetin, hesperidin, epicathequin, gallocatequine; Colored and black berries ( Ampelopsis glandulosa, Ribes nigrum, Vaccinium vitis-idaeae, Rubus ideaeus, Fragaria ananassa, Rubia tinctoria); Natural pyranoanthocyanins: adducts malvidin 3-glucoside pyruvic, peonidin 3-glucoside, 4-vinylcatechin, vitisin-B; Polyacylated anthocyanins ( Cliteria ternatea, Vitis vinifera, Rosa hybrida ) : ternatins A1-3, B1-4, C1-4 and D1-3, tecophilin, cyanodelphinidin, phacelianin, alatanine C, rosacyanin B. CROMENES, IRIDOIDS AND DERIVATIVES: Logwood, bark and wood ( Haematoxylon campechianum): haematoxylin; Brazilwood ( Caesalphinia echinata ): brasiline, and its oxidation derivative brazileine (water-soluble); Kamala, fruits ( Philippine sea cucumber ) : rottton; Sandalwood ( White sandalwood ): sandalwood, sandalwood (isoflavone); Mango ( M. indica ): mangiferine; Gentiana ( Yellow gentian ): gentisin, oleuropeoside, amarogentioside, sweroside; Jenipapo or Jagua, fruits ( American Genipa ): genipine. PTERIDIN AND DERIVATIVES: Vegetables, broccoli, spinach, nuts, avocado, whole grains: bioactive riboflavin (fluorescent yellow). ISOQUINOLINE AND DERIVATIVES: Bloodroot, roots ( Bloodroot Canadian ): Sanguinarine (1%), Berberine. PHENOXAZINE, PHENAZINE AND DERIVATIVES: Liquen ( Rocellia tinctoria, Ochrolechia tartarea, E. prunesti ): orceine, orchile POLYENES, CAROTENOIDS, TERPENOIDS AND DERIVATIVES: Paprika ( Capsicum annum, Capsicum annuum L. ) : capsanthin, Capsorubin; Annato or Annato ( Bixa Orellana ) : bixin, nor-bixin; Carrot ( Daucus carota ) : alpha, beta and gamma carotene; Saffron ( Crocus sativus): orange crocetin; Rosa canina: rubixanthin; Jasmine ( Gardenia jasminoides ) : crocine; Tarragona (Tagetes lucida): lutein; Orange ( Citrus sinensis) : β-citraurine and violaxanthin; Curry ( Turmeric long ): curcumin; Cotton (Gossypium sp.): gossypol. CHALCONE AND DERIVATIVES: Safflower, flowers ( Carthamus tinctorium ) : Safflomine A and B (water-soluble), carthamine (water-insoluble) Compounds III: auxiliary / polyfunctional copigments

[0066] Tannins: guarana ( Paulinia cupana ) , grenade ( Punica granatum ) , gallnuts ( Quercus infectoria ) , sumac ( Rhus Coriaria ) , chestnuts, ( Castanea sativa ) , cloves ( Syzygium aromaticum) ), leaves of symplocos , ( Symplocos cochinchinensis), aubépine ; Crataegus mongyna), cypress and miscellaneousOther condensed or hydrolyzable tannins). Aliphatic acids: citric acid (citrus fruits), tartaric acid (rhubarb, grapes), acetic acid (grape vinegars, rice), malonic acid, succinic acid, ascorbic acid. Aromatic acids: caffeic acid (coffee), chlorogenic acid (chestnut, tea), quinic acid, coumaric acid, synaptic acid, ferullic acid, gallic acid. Phenolic acids: hydroxycinnamic acid, hydroxybenzoic acid.Carbonates (sodium bicarbonate, sodium hydrogen carbonate or potassium), seawater (mixture of salts) or wood ash infusion (which replaces carbonates); Potassium alum or aluminum and potassium disulfate, iron, manganese, or zinc oxides; Reducing sugars: fructose, glucose, rhamnose, galactose, arabinose, xylose and sucrose; Sulfur compounds (sulfur derivatives of garlic, thio-amino acids such as cysteine, N-acetylcysteine, methionine, glutathione), Nitrogen compounds (hydrolysates of vegetable proteins, yeast autolysates, amino acids).

[0067] Amino acids are considered low-toxicity molecules and contain functional groups such as sulfur, thiol, and phenolic hydroxyl groups. All of these groups can be covalently linked to other biomolecules such as proteins (e.g., keratins).

[0068] A single source of colorant, alone or mixed with co-pigments, can be the basis of a great chromatic variability through the use of auxiliary co-pigments, acids, bases, metallic salts or other materials of natural origin.

[0069] The auxiliary copigments used in the copigmentation process according to the invention are preferably of plant origin. The best known are rhubarb rhizome (tartaric acid), thio-amino acids (methionine, glutathione, cysteine ​​or its derivatives), wood ash infusion (which replaces carbonates), vegetable tannins present in gallnuts, green tea, pomegranate peel, or chestnut wood or even Symplocos.

[0070] Acylation with organic acids (aromatic and / or aliphatic) is known to improve the stability of dyes and pigments. Tartaric acid is used in food as a food additive (number E334 13<), and can be used as a pH regulator.

[0071] During the preparation of the colorants according to the invention, the auxiliary pigments are chosen according to the active ingredients present in the plant extract and then mixed according to the compatibility of molecular structures so as to obtain, as appropriate: the improvement of the stability of the compounds (pH, temperature, light, chemical), the improvement of their solubility in a physiologically acceptable environment, the increase in the intensity and / or the retention of the final colors, the increase in the affinity of the dyes towards keratin fibers (hair, beards, eyebrows, nails, feet and hands) and / or skin, or textile fibers to be colored.

[0072] The combination of auxiliary copigments with one or more molecules chosen from the precursors of dyes and / or copigments can be chosen by the person skilled in the art who will be able to establish the biocompatibility of the compounds with each other and choose the sources of compounds and the conditions of the copigmentation reaction according to the desired color.

[0073] In a preferred embodiment of the invention, compounds I, II, and III are products of natural origin so as to prepare a 100% natural coloring product. However, some of the naturally derived compounds may be replaced by synthetic products and used in a reaction according to the invention. Furthermore, conventional synthetic additives used in the composition of hair, skin, or textile dyes may be incorporated into the final composition of the products according to the invention under the careful supervision of a person skilled in the art, who will be able to select them based on their chemical compatibility with anionic or non-anionic polymers, amphoteric polymers, mineral or organic thickening agents, antioxidants, perfumes, buffers, dispersants, preservatives, opacifiers, or various conditioning agents.

[0074] A second object of the invention relates to a copigmentation dye obtained by a preparation process as defined above.

[0075] The process for preparing this dye uses compounds I, II and III under mild reaction conditions.

[0076] In order to distinguish the composition of the invention from the products of the prior art, the coloring product obtained by the copigmentation process according to the invention is named " Co-pigmentation dye ».

[0077] In one particular embodiment, the copigmentation dye is in the form of a liquid solution. This solution can be obtained directly from crude extracts that have been previously processed to obtain only water-soluble substances.

[0078] In another particular embodiment, the coloring product is in frozen form. Indeed, the resulting reaction solution can be directly frozen for preservation.

[0079] In another particular embodiment, the colorant is in the form of an instant powder. This powder can be obtained by freeze-drying or spray-drying, according to methods known to those skilled in the art. Preferably, the colorant is a freeze-dried (water-soluble powder).

[0080] Freeze-drying is one of the best drying methods because it preserves organoleptic characteristics, particularly aroma and color, for extended periods, sometimes up to several years. Refrigeration is not necessary to store freeze-dried products. Freeze-drying also reduces the weight of food, which is advantageous for transport and storage.

[0081] The freeze-dried product is prepared directly from the water-soluble fraction or from the frozen water-soluble fraction ground into small pieces.

[0082] Lyophilized pigments are instant coloring powders available in various shapes (lace-like, star-shaped, or plate-like) depending on the raw material composition, and they offer excellent solubilization in aqueous solutions. Rehydration of these instant colorants is complete upon solubilization in aqueous or hydroalcoholic solutions, making them much easier to use. Lyophilized pigments can be mixed with skincare products (butter, gel, mousse, cream) to create coloring masks for keratin fibers. The colors of the original solutions are perfectly preserved after dissolution. Rehydrating lyophilized pigments is much easier than rehydrating corresponding compounds in dehydrated form. Their porous structure allows for rehydration with either cold or warm water in just a few seconds. Consumers appreciate their visual appearance and consistency.

[0083] The polyfunctional catalyst, particularly amino acids and especially thiomanino acids, incorporated into the reaction medium, provides a greater affinity of the water-soluble composition to the hair fibers and, found, They offer superior wash resistance compared to traditional poultice preparations. Unlike poultices, instant dyes do not contain insoluble components, resulting in a particularly pleasant texture that is easier to condition and apply.

[0084] In a particularly preferred embodiment of the invention, the coloring product is obtained from 100% natural ingredients. In particular, such a product can be obtained from 100% plant-based ingredients. Bibliography

[0085] M. J Middelveen, P. J Mayne, D. G Kahn, R. B Stricker, Characterization and evolution of dermal filaments, Clin Cosmet Investig Dermatol ; 2013; 6:1-21. Middelveen MJ, Rotaru GM, McMurray JL, Filush KR, Sapi E, et al. Canine Filamentous Dermatitis Associated with Borrelia Infection. J Vet Sci Med Diagn 2016 ; 5:6. Pradeepa V, Senthil-Nathan S, Sathish-Narayanan S3, et al., Potential mode of action of a novel plumbagin as a mosquito repellent against the malarial vector Anopheles stephensi ; Pestic Biochem Physiol. 2016 Nov;134:84-93. Mohd et al. (2012), Assessment of colorimetric, antibacterial and antifungal properties of woollen yarn dyed with the extract of the leaves of henna (Lawsonia inermis), Journal of Cleaner Production 27 (2012) 42.-50 Scientific Committee on Consumer Safety (SCCS), SCCS / 1511 / 13, OPINION ON Lawsonia inermis (Henna), 19.09.2013

[0086] Des exemples de produits colorants selon l'invention sont décrits dans le Tableau 1. TABLE 1: Compositions of dye products according to the invention. LIQUID FORM OF COPIGMENTATION DYES Compounds A* (quantity of crude extract) Compounds B * Obtained color Pantone Classification Henna (25 to 100 mg / ml) + coffee (2.5 to 15 mg / ml) Tannins (25 to 100 mg / ml) + polyphenols (2.5 to 15 mg / ml) + amino acid (Cysteine: 2.5 to 150 mg) chocolate 1405C Henna (25 to 100 mg / ml) + green coffee (5 to 250 mg / ml) Tannins (25 to 100 mg / ml) + polyphenolic acid (5 to 250 mg / ml) + amino acid (cysteine: 2.5 to 150 mg / ml) taupe 17-0929 Annato (7 to 50 mg / ml) + green coffee (5 to 250 mg / ml) Polyphenolic acid (5 to 250 mg / ml) + amino acid (csytein: 2.5 to 150 mg / ml) mandarin 13-0720 Henna (25 to 100 mg / ml) + carmine (E120) (5 mg / ml - 300 mg / ml) Sugars + tannins + amino acids (cysteine) Venetian red 19-1664 henna (25 to 100 mg / ml) + chestnut (20 mg / ml - 360 mg / ml) Tannins + amino acids (cysteine: 2.5 to 150 mg / ml) Golden yellow 14-0848 Henna + vine Antocianins (10 - 200 mg / ml) + tannins + amino acids (cysteine) lilac 15-3817 COPIGMENTATION DYES IN LYOPHILSAT FORM

[0087] Henna Tannins orange 17-1463 / 14-0848 Henna + green coffee Tannins + polyphenolic acid + amino acid (cysteine) mole 17-0929 Henna + coffee Tannins + polyphenols + amino acid (cysteine) chocolate 1405-C Henna + walnut husk Tannins + amino acid (cysteine) mole 17-0929 Annato + green coffee polyphenolic acid + amino acid (cysteine) Primrose yellow 13-0739 *Subjected to gentle physical techniques for the extraction of active ingredients

[0088] Upon reading Table 1, we observe that: The colors obtained by using individual dye precursors are quite different compared to the colors obtained by copigmentation dyes; The colors obtained by using copigmentation dyes are homogeneous, which indicates that the coloring result is not associated with the coloring of individual components;

[0089] Instant powders exhibit the same colors after dissolution as liquid dyes. This indicates that there is no loss or alteration of the coloring agents during the filtration, dehydration, and packaging processes. The removal of insoluble residues from natural extracts leads to an enrichment of water-soluble constituents and, consequently, an improved contact surface between the active molecules and the keratins, resulting in better coloring efficiency.

[0090] The natural aromas present in the plant extracts are maintained and provide notable organoleptic characteristics depending on components I and II (example: turmeric, coffee, roses).

[0091] The presence of co-pigments (tannins, chalcones, carotenoids, aliphatic acids etc...) stabilizes the colorant precursors and at the same time strengthens the coloring action by a potentiation effect of the resulting colors and a greater variability of colors.

[0092] Without the polyfunctional catalyst, only the direct dye (e.g., Lawsone) impregnates the fibers permanently. The types of constituents in the copigments (flavonoids, anthocyanins, carotenoids, etc.) play an important role in the final color of the copigment dyes, even though these copigments are not directly coloring agents. However, the amino acid must play a role in the association between the dye / copigment molecules and increase the affinity of the final dye for the hair fibers.

[0093] The preparation of instant natural dyes (co-pigmentation dyes) from lyophilized products is easier, faster and the application more comfortable, with the possibility of using care products such as treatment masks by adding alginates (polysaccharides), butters (shea) or conditioners as an application support.

[0094] The non-use of aggressive agents (ammonia, hydrogen peroxide, parabens) allows for the preservation of keratin fibers and maintains the health of the scalp.

[0095] Shelf life depends particularly on the packaging method, but most freeze-dried food products (vegetables, milk, instant coffee) that are properly packaged have a very long shelf life. Stability of active compounds and shelf life.

[0096] Freeze-drying preserves virtually all the qualities of the fresh product (coloring capacity, aroma, freshness). Furthermore, freeze-drying maintains vitamins A, B, and C at levels very close to those of the fresh product, even after many months of storage. Although this process preserves microbial strains, it also destroys a significant portion of the contaminating bacterial population. Consequently, the treated foodstuffs are purified, resulting in improved hygiene.

[0097] The invention also relates to a copigmentation dye characterized in that it is instant, water-soluble and does not comprise an insoluble fraction.

[0098] These pigment dyes are water-soluble, their composition is more stable than other natural dyes, they have an improved affinity for keratin fibers, and they last longer. The color results are homogeneous, and the colors are unique compared to state-of-the-art natural products. Furthermore, a wide variety of formulations are possible thanks to the freeze-dried / dried format.

[0099] A third object of the invention relates to a hair coloring kit, this kit comprising: a co-pigmentation colorant (lyophilized) as defined above, a natural gel or butter for cosmetic use, utensils for mixing the components and applying the resulting mask to the hair.

[0100] The gel or butter included in the kit serves as a base for applying the coloring product. This could be, for example, shea butter or an alginate gel.

[0101] In a preferred embodiment, the colorant is a 100% natural product. Similarly, the gel or butter used as a carrier for the colorant is preferably a product of natural origin, and can be randomly formulated to obtain personalized tones or highlights.

[0102] This kit may also contain an explanatory leaflet with instructions for the use of the dermo-phyto-pharmaceutical coloring product.

[0103] A fourth object of the invention relates to the use of dyes as defined above in the cosmetic, agri-food, veterinary and textile dyeing fields.

[0104] Natural colorants find particular application in cosmetics, in response to consumer demand for natural colour compositions free from chemicals, especially for coloring hair and tattooing skin.

[0105] Using instant hair coloring products is very simple; they can be mixed with hair care products. Natural alginates (from seaweed), butters (shea, murumuru, cocoa, etc.), mousses, and various conditioners can be used as carriers. However, hydrophilic materials are more suitable as carriers for water-soluble freeze-dried dyes; for example, sodium alginates, polysaccharides obtained from seaweed, provide a beautiful gel consistency and blend perfectly with freeze-dried dyes.

[0106] Applying instant natural hair dyes is easier than applying traditional natural dyes. Instant dyes can be easily mixed into conditioner. Simply combine the dye with the conditioner. Instant dyes can also be incorporated into a hair mask, which is then applied to the hair and left on for at least 30 minutes. Before rinsing, the hair can be blow-dried to speed up the coloring process.

[0107] In addition to the cosmetic field, these instant colorants, preferably 100% natural, can be used in the food industry to color drinks, sweets, pasta etc... or used in pharmaceutical formulation.

[0108] In the field of textile dyeing (wool, silk, linen), instant dyes or dried powders can be used for eco-friendly textile dyeing (or bio-dyes). These natural dyes can optionally be combined with non-natural dyes (semi-synthetic dyes).

[0109] It is also possible to use the coloring products according to the invention in the veterinary field to dye the hair of dogs, cats and other domestic animals.

[0110] In summary, the invention introduces the following innovations: The stabilization of natural coloring materials through a process that reacts chemocompatible entities in the presence of a suitable catalyst. The development of natural dyes and pigments that are currently underutilized due to a lack of stabilization methods. A wide range of shimmering colors obtained solely from natural ingredients, with enhanced or even modulated color intensity. These can be described as "new natural colors." These color variations are obtained by blending identified coloring materials with other naturally derived coloring molecules. These color variations are obtained by blending compatible materials with other naturally derived coloring molecules. Innovative packaging for ready-to-use dyes through simple aqueous dissolution of the lyophilized powders.The effectiveness of hair coloring is optimized by increasing the contact surface between the active agents and the hair. Indeed, the use of gels, butters, and creams, rather than a poultice, offers a new technical and comfort advantage. Use in dermocosmetics / pharmaceutical

[0111] Naphthoquinone pigments have multiple properties (bactericidal, fungicidal, insect-repellent, pollution-reducing, etc.), in addition to their coloring capacity. These substances, as well as their active derivatives, can be used to treat bacterial dermatoses in humans (Lyme disease, filamentous dermatitis due to borreliosis), or animal dermatoses (for example, bovine or canine digital dermatitis).

[0112] Often presenting with multiple symptoms, these dermatoses are characterized by the formation of filaments accompanied by itchy eruptions. Studies have shown that these filaments can be composed of colored keratins and collagen.

[0113] An increasing number of people worldwide have been affected by tick-borne dermatopathy (borreliosis) for about fifteen years. This is characterized by the presence of fibers and filaments from the skin and is often associated with other symptoms (arthralgia, extreme fatigue, and impaired cognitive function) (J Dtsch Dermatol Ges. 2010 Apr;8(4):234-42). .). Histological and electron microscopy analyses revealed the origin of these filaments. They appear to be composed of keratin and collagen, resulting from the proliferation and activation of keratinocytes and fibroblasts in the epidermis. Spiroquets were detected in these affected individuals (Clin Cosmet Investig Dermatol. 2013;6:1-21).).

[0114] The sources of active naphthoquinones are variable. The substance juglone is present in extracts of *J. regia* or *J. nigra* (Fischer TC et al., 2012); lawsone is present in extracts of *Lawsonia inermis* (Sritrairat N et al., 2011); plumbagin has been identified in *Plumbago zeylanica* (Pradeepa V. et al., 2016); and other active quinones are also found (Futuro et al., 2018). Naphthoquinones show potential as adjuvants in the treatment of these filamentous dermopathies due to their bactericidal, fungicidal, or repellent actions combined with their natural affinity for keratin fibers. Veterinary use

[0115] Similarly, in the veterinary field, bovine digital dermatitis is associated with spirochete infection. The proliferative stage has demonstrated the formation of keratin filaments on the skin and between the hooves of affected animals. The etiology of this dermatitis is not yet known, but the presence of spirochetes and other co-infections have been implicated in the pathogenesis of this veterinary condition. ( Middelveen MJ1, Stricker RB, 2011 ).

[0116] A similar dermatitis has been identified in canines, associated with Borrelia infection (Marianne J Middelveen et al., 2016). Recent studies have demonstrated that keratin biofibers are produced by epithelial cells in response to spiroquette infection.

[0117] Thus, a fifth object of the invention relates to the use of a topical dermatological product composed of conjugated naphthoquinones for the treatment of bacterial dermatoses characterized by the formation of filaments. These products are obtained from naphthoquinone pigments of natural or synthetic origin.

[0118] In one particular aspect, the invention relates to a method for preparing a topical dermatological product (in the form of a cream, gel, powder or spray) having bactericidal, fungicidal or ectoparasite-repellent properties.

[0119] This product can be integrated into a coloring formulation, or into a coloring kit in order to combine the coloring property with insect repellent action, antifungal action or even bactericidal action.

[0120] The process consists of reacting at least one compound I, in the presence of an oxidizing agent, with a compound III. These compounds I and III are chemocompatible with each other, in a neutral medium. The pH becomes acidic following the addition of amino acid salts, at a temperature between 30°C and 55°C (exceptionally up to 70°C), for a duration of between 10 and 45 minutes, in which: Compound I is a colorant precursor, said precursor being a naphthoquinone, for example a natural naphthoquinone such as lawsone, juglone, lapachone, plumbagin, menadione, methoxy-naphthoquinones... Compound III is a natural polyfunctional catalyst, said catalyst being a thioamino acid.

[0121] Optionally, the process may also involve a compound II selected from naphthoquinones, quinones, antraquinones, indoles, bis-indoles, xanthones, flavonoids, pyranoanthocyanins, crommenes, iridoids, preridins, isoquinolines, phanoxalins, phenazines, polyenes, carotenoids and chalcones.

[0122] The oxidant could, for example, be hydrogen peroxide.

[0123] Preferably, the process for preparing an instant and water-soluble dye according to the invention consists of reacting the water-soluble parts of plants rich in precursors of chromophore dyes and / or auxochrome groups as sources of compounds I, and / or II and / or III.

[0124] In a particular embodiment of the process, the reaction temperature is between 30°C and 55°C, preferably between 40°C and 55°C, even more preferably between 45°C and 50°C, which may vary depending on the nature and stability of the mixed compounds.

[0125] In a preferred embodiment, the pH of the reaction is between 8 and 9.

[0126] The resulting copigmentation dyes are naphthoquinones conjugated to a thio-amino acid and possess bactericidal properties that act through interaction with keratins, whether skin, hair, or fur. They therefore have applications in human and animal health.

[0127] Copigmentation dyes obtained using this process can be used as a bactericidal, fungicidal and repellent agent by direct application to the skin, hair or fur.

[0128] They are then impregnated directly onto the hair (keratin) of affected animals, particularly cattle, dogs, or cats. Their use in humans is facilitated by direct impregnation as hair dyes. These products, used for millennia in Ayurvedic medicine and herbal therapy, are safe for human and animal health.

[0129] Copigmentation dyes can also be used to color natural fibers or natural fabrics.

[0130] This coloring process involves impregnating the fibers with the active natural molecules present in the color-enhancing dyes. The fabric must be chosen according to the desired function and local climate (e.g., pajamas). The fiber in question must be virgin (undyed) and of natural origin, either plant-based (cotton) or animal-based (wool, silk).

[0131] These composites are composed according to the increased affinity of certain types of fiber used (e.g. cotton, wool, silk, alparga, etc.).

[0132] To dye delicate natural fibers, gentle temperatures (30°C for silk; 40°C for cotton) must be used during the dyeing process to avoid degrading or altering the function of the pigments used or the integrity of the fibers. The present invention will be better understood upon reading the following examples, provided by way of illustration and which should in no way be considered as limiting the scope of the present invention. EXAMPLES Example 1: Extraction of a compound A - dye obtained from crushed henna leaves ( Lawsonia inermis )

[0133] The ground henna leaves (10% of the weight of the fibers to be colored) are reduced to a fine powder by grinding or maceration (v / v). Distilled water (100 mL) is heated (65 to 75°C) or brought to a boil. The water is added to the ground powder, and the mixture is stirred for 15 to 30 minutes until homogenized. A hydroalcoholic solution (5 to 30%) can be used instead of water.

[0134] To extract the maximum amount of compounds, the resulting paste can be macerated until homogenized. The thick paste is then left to rest for 3 to 24 hours at room temperature. After 24 hours, the solution is filtered to remove the insoluble residue. This step, known as "enzymatic catalysis," allows the release of the active compounds (colorants / copigments) from its natural glycosides. The addition of an alkaline solution (NaHCO3 or Na2CO3) can inhibit the enzymatic action and prevent or delay the release of the active ingredients (colorants / copigments). This is therefore not recommended depending on the type of raw material used.

[0135] Generally, molecules with coloring power are solubilized in an aqueous or hydroalcoholic phase. However, some compounds are poorly soluble or insoluble in water. In this case, it is necessary to transform the ingredients. Example 2: Extraction of a compound II - aqueous extract of ground roasted coffee beans

[0136] Several materials of natural origin having the characteristics of a pigment or co-pigment (food colorings, natural pigments in cosmetics, etc.) can be used to obtain compound I or II

[0137] The extraction of auxiliary pigments (Compound III) can be carried out by direct infusion-filtration (e.g., coffee) without the need for a resting time. It is also possible to use commercially available food colorings.

[0138] If necessary, the water-soluble extractive solution is separated from the insoluble parts by filtration and stored. The resulting water-soluble solution is maintained at a temperature between 6 and 10 °C, or 4 and 8 °C, to prevent contamination by microorganisms. Example 3 : Preparation of a natural dye a. Reaction implemented

[0139] The type I compound(s) are dissolved in a volume of distilled water. The solution is then filtered through paper or cotton to remove insoluble residues.

[0140] The co-agment(s) (type II compound(s)) and the catalyst (type III compound) are introduced at room temperature with stirring. The temperature is then rapidly increased to 45–50°C (maximum 70°C) and maintained with stirring for a short period (10–15 min). The mixture is then cooled to room temperature with stirring for 30–60 min.

[0141] The dye can be used immediately after cooling, stored in the refrigerator for short-term use, or frozen for subsequent freeze-drying.

[0142] The dye solution can then be lyophilized. b. freezing of reaction products

[0143] After cooling, the resulting solution is either used immediately or frozen to maintain all the coloring and odorating properties of the plant extracts. c. Freeze-drying of dyes

[0144] Prior to freeze-drying, the frozen coloring compositions are rapidly crushed into small pieces using an electric grinder to prevent thawing. The goal is to obtain relatively homogeneous pieces. These crushed ice cubes are then placed in the freeze-dryer chamber (or flask).

[0145] These broken ice cubes were freeze-dried using a Labconco Freezone 4.5L freeze dryer. The water was sublimated at a low temperature (-50°C) and a high vacuum (2 x 10⁻² mbar) using an Alcatel pump. The compounds were left in the freeze dryer until a completely dry freeze-dried powder was obtained.

[0146] Alternatively, filtered water-soluble extracts can be used directly for freeze-drying, without the prior freezing step.

[0147] The yield of the prepared and analyzed freeze-dried products varies between 25 and 60% (for some raw materials up to 80%) of the weight of the crude extract, a result dependent on the starting raw product and the extraction technique used. Rendement = lyophilisat / extrait brut sec * 100

[0148] The freeze-dried extracts / dry extracts are kept hermetically sealed until use, preferably under an inert atmosphere (argon) or under vacuum. d. Spray drying

[0149] A less expensive alternative to freeze-drying is spray drying, which dries a liquid to obtain a powder. This technique is commonly used to produce powdered milk, soup, juice, or coffee.

[0150] The water-soluble rehydration solution (SSR) is introduced from above under pressure, with a jet of hot air. The falling droplets dry to form a fine powder that cools as it descends. The moist granules are then dried as they descend through a second tower and are sieved to obtain final granules of uniform size. This technique requires less gentle conditions than freeze-drying, which can lead to less effective preservation of the active compounds (dyes / co-pigments). Example 4: Preparation of a hair dye a. Dyes and pigments used

[0151] Compounds I and II: crushed henna leaves ( Lawsonia inermis ) and roasted coffee beans (Csp) Compound III: Amino acid (food grade) b. Reaction implemented

[0152] The crushed henna leaves (25 g) are mixed with boiling distilled water (100 mL to 150 mL), then stirred vigorously for 15 minutes and left to stand for 24 hours. The solution is then filtered through filter paper or a cotton swab. Roasted coffee extract (5 g / 30 mL water) is added to the henna extract. Finally, compound B, an aqueous solution of a thioamino acid (0.1 g), is added to the henna-coffee mixture.

[0153] The mixture is heated to 50°C (maximum 70°C), with stirring, for 15 minutes and cooled to room temperature.

[0154] The instant colorant (lyophilized henna-coffee-amino acid) has a uniform star-shaped appearance, a chocolate brown color (very different from henna alone) and retains the coffee aroma of the original extract.

[0155] For long hair you will need at least 50g of henna powder and 10g of coffee powder. Example 5: Applying instant hair color

[0156] Using the freeze-dried products is very simple. The following steps are recommended: i. Dissolving the lyophilized powder in a small volume of water for direct application or preparation of a mask. ii. Preparation in situof a coloring mask: ∘ Solubilize the lyophilized coloring materials with a small volume of water (5 ml) and add a butter (e.g., shea) with a spatula. Homogenize. ∘ Alternatively, the lyophilized product can be dissolved directly in a water-soluble gel (e.g., 2% carrageenan gel) or butter (e.g., shea butter). The resulting mask has a suitable consistency, and the initial organoleptic characteristics are maintained, particularly the color and scent. iii. Application of the solution or mask directly to dry hair o Apply the coloring mask in sections to the scalp using a brush and distribute with a fine-toothed comb to cover all of the hair. o Drying (with a hairdryer) accelerates the coloring process and allows for more intense colors. iv. Leave on for 30 minutes (minimum, ideally 45 minutes) v. Rinse with lukewarm water to remove excess and dry hair normally

[0157] Alternatively, the hair can be washed with regular shampoo and rinsed with lukewarm water.

[0158] Table 3 below summarizes the steps required for applying the dyes. TABLE 3: Instructions for use of coloring products Stage Products Method Result i Freeze-dried powders: Henna + Coffee + mordant (~7 g) Water: 15 to 20 mL Adding water to the freeze-dried product (room temperature or slightly warm) Homogeneous solution (I). ii Carrageenan gel 0.5 to 2% Addition of the gel into solution I. Homogeneous mask (II) Mix by hand until a thick and homogeneous consistency of colors is obtained iii - Application to hair of I or II Chocolate brown hair with beautiful highlights, original color nuances, sweet coffee scent - Distribute the product using a fine-toothed comb Solution (I) OR Mask (II) -Drying with a hairdryer (a)< - Rest for 30 to 45 minutes - Rinse with lukewarm water or shampoo (a) The objective here is not to dry the hair, but to accelerate the penetration of the dyes into the fibers Example 6: Comparative test between instant natural colorants according to the invention versus permanent hair dye

[0159] A comparative hair coloring test was carried out with the following products: Dye (X) acquired through trade, bearing the name 'hair coloring with plant extracts' compounds of synthetic molecules with hydrolysates of natural proteins Solution coloring ( Y The object of the invention, composed solely of natural dyes and pigments and a catalyst (amino acid or its salt). Coloring solution (Z) reconstituted from the lyophilized powder obtained with composition (Y)

[0160] A piece of sheep's wool fabric (washed and virgin), washed with neutral shampoo and virgin (without prior coloring) was used as a model for human hair. Compound A galenic support Natural Keratin (TEST) Color Dye Mixture of synthetic molecules (derived from p-aminophenol, chlororesorcinol, amino-toluene, ethanolamine, etc.) Gel (15 ml) prepared in situ with hydrogen peroxide (H2O2) - Application on fiber Chocolate brown with golden notes ( named dark golden blonde ) (available on the market)* - Rest 30 min - Heated to 50°C (named 'X') Invention : • Henna (25 mg / ml) Distilled water - Application on fiber Chocolate brown Natural colorants according to the invention (named " Y " • Coffee extract (200 mg / mL) - Heated to 50°C - Rest 30 min • Amino acid (7mg) (acidic pH) Invention : Lyophilized powder (100 mg) of B lyophilized powder dissolved in water (4 mL) - Application on fiber Chocolate brown Instant dyes (called "Z") - Heated to 50°C - Rest 30 min * Active colorants: a solution containing a mixture of synthetic molecules that are mixed in situ with hydrogen peroxide during application

[0161] The compositions of active ingredients and adjuvants of the products of the prior art and those of the invention are very different. CHARACTERISTIC THE INVENTION TEST PRODUCT Origin of materials 100% natural origin Synthetics & natural active ingredients Oxidizing agents None (natural pigments) Oxidizing agent (color developer) Heat 50°C 50°C Break time 30 min 30 min Example 7 : Preparation of a dye for dermo-phytopharmaceutical use

[0162] In the presence of an oxidizing agent (e.g., H₂O₂), the lawsone molecule present in henna extract can generate a conjugated derivative that also has bactericidal properties and a greater affinity for keratin fibers. I, III 30–50°C / 10–15 min / pH 7–9 [H₂O₂] => Naphthoquinone conjugate Walnut / juglone [50 to 100 g dissolved in distilled water] Henna / lawsone [50 to 100 g dissolved in distilled water] Tannin: 2.5 to 10 g Thio-amino acid: 10-30 mg Distilled water: q.s. 30 ml

[0163] The resulting reaction solution is treated by freeze-drying / spray-drying and then applied with various formulation carriers (butter, gel, etc.) to the hair or skin.

[0164] In the presence of an oxidizing agent (e.g., H2O2), the lawsone molecule present in henna extract can generate a conjugated derivative that also has bactericidal properties and a greater affinity for keratin fibers.

Claims

1. Process for the preparation of a water-soluble instant dye consisting in reacting at least one compound I and one compound II with at least one compound III, these three compounds being chemocompatible with each other, in a weakly acidic medium whose pH is between 3,5 and 6.5 at a temperature between 30 ° C and 55 °C, for a period of time between 10 and 45 minutes, wherein: - compound I is a dye precursor, - compound II is a copigment. The compounds I and II being chosen from naphtoquinones, quinones, anthraquinones, indoles, bis-indoles, xanthones, flavonoids, pyranoanthocyanins, chromens, iridoids, pteridines, isoquinolines, phenoxazine, phenazines, polyenes, carotenoids and chalcones; - compound III is a polyfunctional natural catalyst selected from tannins, aliphatic acids, aromatic acids and phenolic acids, in particular an amino acid or its salt.

2. The process of claim 1 in which said compound III is a thioamino acid.

3. Process according to one of claims 1 or 2 further comprising a prior step of extracting at least one compound I or II from plants extracts.

4. Process according to one of claims 1 to 3 further comprising a step of lyophilization or spray drying of the dyestuffs so as to obtain an instant powder.

5. Process according to one of claims 1 to 4 in which the compounds I, II and III are exclusively of natural origin.

6. Copigmentation dye obtained by the process defined at one of claims 1 to 5.

7. Dyestuff as defined in the claim 6, characterized by its form liquid or instant powder.

8. Dyestuff as defined in claim 6, characterized in that it is instant powder, water-soluble and that it does not include an insoluble fraction.

9. Process for preparing a water-soluble instantaneous dye, the process consisting in reacting at least one compound I and one compound III, said compounds I and III being chemocompatible with each other in a weakly basic medium whose pH is between 7.5 and 9, at a temperature between 30 ° C and 55 ° C, exceptionally up to 70° C, for a period between 10 and 45 minutes, wherein: - the compound I is a dye precursor, said precursor being a naphthoquinone, for example a natural naphthoquinone such as lawsone, juglone, lapachone, plumbagine, menadione, methoxy-naphthoquinones. - compound III is a polyfunctional natural catalyst, said catalyst being a thio-amino acid.

10. Copigmentation dye according to claim 9 characterized in that it is a conjugated naphthoquinone.

11. Hair coloring kit comprising: - coloring products as defined in one of claims 7 to 8 and 10 under instantaneous powder (lyophilisates) - a gel or a butter for cosmetic use - utensils to mix the components and apply the mask obtained.

12. Dye according to one of claims 6 to 8 and 10 for use in the field of phytopharmaceutical, pharmaceutical and veterinary.

13. Dyestuff according to claim 10 for its use according to claim 12 for its bactericidal, fungicide or antiseptic properties for application to the skin, hair, velus hair, natural keratin fiber or xenofibers.

14. Non-therapeutic use of a dye according to one of claims 6 to 8 and 10 in the cosmetic field, for skin tattooing, in the agri-food, phytopharmaceuticals industry and in the field of textile dyeing.

15. Use of a dye according to claim 14 for coloring natural tissues or fibers.