WO2008034702A1

WO2008034702A1 - Process for the preparation of a cosmetic composition comprising plant extracts and hydrolysable compounds

Info

Publication number: WO2008034702A1
Application number: PCT/EP2007/059011
Authority: WO
Inventors: Quang Lan Nguyen; Véronique Chevalier
Original assignee: L'oreal
Priority date: 2006-09-20
Filing date: 2007-08-29
Publication date: 2008-03-27

Abstract

The present invention relates to a process for the preparation of a composition for topical application, characterized in that it comprises (1) a stage of percolation of fluid under pressure through at least one plant substance in the solid or pasty form and (2) the incorporation of the plant extract obtained in stage (1) in a preparation A comprising at least one hydrolysable hydrophilic compound. The hydrolysable hydrophilic compound is in particular a sugar derivative, such as glucopyranosyl-l-ascorbic acid, adenosine, rutin and isoquercitrin. By virtue of the percolation stage, the plant extract does not detrimentally affect the stability of the hydrolysable hydrophilic compound or that of the composition comprising it.

Description

Process for the preparation of a cosmetic composition comprising plant extracts and hydrolysable compounds

A subject-matter of the present invention is a process for the preparation of a composition intended for the cosmetic treatment of keratinous substances, in particular the skin and human keratinous fibres, such as the hair, and also a method for the cosmetic treatment of keratinous substances starting from this composition.

There is a constant search in cosmetics to improve the cosmetic properties of keratinous substances. The use is thus known, in compositions for topical application, of treatment agents and in particular of plant extracts which make it possible to keep the skin in a good condition or, if appropriate, to improve the condition of the skin by combating in particular signs of ageing of the skin.

In particular, these treatment agents can be used for the treatment of the skin and other keratinous substances, such as the hair, eyelashes, lips and nails, for example for nourishing or moisturizing the skin, protecting it from external agents, removing dead skin, reducing wrinkles and fine lines and also coloured blemishes (defect of pigmentation or blemishes appearing with age, in particular on the hands, neck or face) and generally for providing the skin and other keratinous substances treated by the compositions comprising them with all the benefits related to these treatment agents.

The use of plant extracts is known in cosmetics, in particular for obtaining softening, anti- inflammatory, antipruritic, antiseptic, antiperspirant , astringent, soothing, healing, toning, stimulating, scenting, foaming, odorous, absorbent, thickening, antioxidant, emulsifying, photoprotective and/or texturing properties. It is also known, for example, to treat signs of ageing of the skin using plant extracts comprising polyphenols.

However, natural plant extracts are commercially obtained under cold conditions with a mixture of solvents, for example in an aqueous/alcoholic medium or with supercritical CO₂ and may comprise, for this reason, inevitable traces of hydrolytic or oxidasic enzymes which are naturally present in the plants used. These enzymes, even in trace amounts, can cause problems in the cosmetic compositions comprising them. For example, these enzymes can denature the plant extract comprising them, for example resulting in a phenomenon of browning, as can be observed with a peeled apple left in contact with the air. In particular, they can result in the instability of hydrolysable active principles which may be also be present in the composition and which are sensitive to enzymatic hydrolysis, the consequence of which is an at least partial denaturation of these active principles and thus reduced effectiveness of these active principles. For example, adenosine destabilizes in the presence of enzymes .

The need thus remains to have available cosmetic compositions comprising plant extracts which are not denatured and which do not result in the instability of the other active principles of the formulation.

The Applicant company has discovered, surprisingly, that, by using a novel process for the preparation of plant extracts to be incorporated in a cosmetic composition, it is possible to obtain, in a very short time, less than 2 minutes, plant extracts which no longer comprise enzymes and which thus no longer exhibit the disadvantages mentioned above.

A subject-matter of the present invention is thus a process for the preparation of a composition for topical application, characterized in that it comprises

(1) a stage of percolation of fluid under pressure through at least one plant substance in the solid or pasty form and (2) the incorporation of the plant extract obtained after the stage (1) in a preparation A comprising at least one hydrolysable hydrophilic compound chosen from nucleosides and glucosides.

The term "plant extract" is understood to mean, within the meaning of the invention, any extract obtained from a plant substance and the term "plant substance" is understood to mean any substance belonging to the plant sphere (trees, plants, weeds, flowers) .

Another subject-matter of the invention is a composition capable of being obtained by the process according to the invention.

The process is carried out simply. A fluid under pressure, the temperature of which is preferably greater than or equal to 3O⁰C, preferably ranging from

3O⁰C to 15O⁰C and more preferably still ranging from

4O⁰C to 12O⁰C, is passed, for a very short period of time, less than one minute, through at least one plant substance in the solid or pasty form, preferably in the solid form and more preferably in the pulverulent form.

By virtue of this process, the plant extracts obtained after percolation are devoid of any trace of enzyme and these extracts and the compositions comprising them are stable .

This process results in a ready-to-use composition intended to be used rapidly after its preparation, for example within the 5 minutes following its preparation, in particular after cooling to a cosmetically acceptable temperature, preferably less than 6O⁰C. The composition can be used up to one week after its preparation. As the composition is intended for topical application and in particular application to keratinous substances, it comprises a cosmetically acceptable medium. The term "cosmetically acceptable medium" is understood to mean a medium which is non-toxic, which is capable of being applied to keratinous substances and which is pleasant to use. The term "keratinous substance" is understood to mean the skin, scalp, lips and/or superficial body growths, such as the nails, eyelashes, eyebrows and hair .

The composition of the invention can constitute in particular a cosmetic or dermatological composition.

Given the very short preparation time, the cosmetic treatment compositions can be prepared "on request" by mixing the plant extracts and other active principles according to the cosmetic properties desired.

According to another embodiment, the plant substances can be packaged in a ready- for-use device and it is not necessary to determine beforehand the concentrations of the plant extracts in solution, which limits the measurement errors of the user.

In addition, the process according to the invention makes it possible to avoid the use of multicompartment bottles, which renders the process particularly economical and safer for the user.

An important advantage of this preparation process is the production of compositions comprising good cosmetic properties. In particular, the keratinous substances treated with a composition obtained by the process according to the invention are protected, nourished and strengthened and exhibit a particular pleasant visual appearance . Another subject-matter of the invention is the cosmetic use of the composition obtained according to the process of the invention for the cosmetic treatment of keratinous substances and in particular the skin.

Other subject-matters, characteristics, aspects and advantages of the invention will become even more clearly apparent on reading the description and examples which follow.

According to the invention, the process for the preparation of a topical composition comprises a stage of percolation of a fluid, preferably at a temperature at least equal to 3O⁰C, better still ranging from 3O⁰C to 15O⁰C, better still from 4O⁰C to 12O⁰C, under pressure, in particular under a pressure of at least 3 bar (3 x 10⁵ Pa) , through at least one plant substance in the solid or pasty form.

Percolation is a movement of fluid through a saturated porous medium which allows the fluid to pass, under the action or the effect of the pressure. The fluid can be composed of steam, optionally accompanied by liquid water, or of one or more physiologically acceptable, in particular organic, liquid and/or gaseous solvents or also of a mixture of steam, optionally accompanied by liquid water, and of one or more physiologically acceptable liquid and/or gaseous solvents. Preferably, the fluid comprises at least steam, which can be accompanied by liquid water, and more preferably still it is steam, which can be accompanied by liquid water.

Mention may be made, as organic solvent, for example, of Ci-C₄ alcohols, such as ethanol and isopropanol ; polyols and polyol ethers, such as 2-butoxyethanol , propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and diethylene glycol monomethyl ether; aromatic alcohols, such as benzyl alcohol or phenoxyethanol ; and their mixtures. The plant substance is in the solid form or in the pasty form, preferably in the solid form and more preferably still in the pulverulent form.

In the present invention, the term "solid form" is understood to mean a compound or a composition which is provided in the form of a lozenge (or tablet) , of a sheet or of a powder, a powder being a solid finely divided into particles, in contrast to a composition in the form of a cream or of a gel, which are soft compositions. Furthermore, the term "pulverulent" is understood to mean a compound or a composition which is provided in the form of a powder (composed of particles or grains) .

The term "pasty form" is understood to mean, within the meaning of the present invention, a consistency intermediate between a solid phase and a liquid phase. The viscosity of this pasty phase is preferably greater than 0.1 Pa-s and more preferably still greater than 1 Pa-s, at 25⁰C with a shear rate of 10 s^"1.

The process of the present invention can be carried out from a conventional device which makes it possible to generate a fluid under pressure, at a temperature preferably greater than or equal to 3O⁰C and more preferably still ranging from 3O⁰C to 15O⁰C. Such a device comprises a pressure-resistant chamber equipped with a heating unit and a circuit for conveying the fluid produced to the plant extract.

According to another embodiment, the device comprises a tank for liquid (s) and a pump which makes it possible to convey the liquid or liquids to the chamber.

The liquid present in the tank is either water, or a physiologically acceptable solvent or a mixture of several physiologically acceptable solvents, or also a mixture of water and of one or more physiologically acceptable solvents. Preferably, the liquid comprises at least water and more preferably still it is water.

A particularly useful device for implementing the process of the present invention is a coffee machine of the "expresso" type. Such machines are well known in the art. For example, these machines are described in the documents AT-A-168 405, US-A-2 688 911, DE-A-32433870 and IT-A-I 265 636 and in Applications

FR 06/50303, FR 06/50304, FR 06/50306 and FR 06/50308.

According to a specific embodiment of the invention, the percolation stage is carried out with a fluid at a temperature at least equal to 3O⁰C, preferably between 3O⁰C and 15O⁰C, under a pressure of at least 3 bar and better still of at least 4 bar, preferably under a pressure of greater than 10 bar. The pressure is at most 30 bar; it can, for example, range from 3 to 30 bar, preferably from 4 to 30 bar and very particularly from 10 to 30 bar.

The plant substance or substances, in the solid or pasty form, can be used directly, in the device generating the fluid under pressure, in a receptacle intended for this use. They can also be packaged in a specific packageing device of the single-dose type comprising a closed housing delimited by at least one wall at least partially permeable to a fluid under a pressure of at least 3 bar. Such devices are, for example, described in the documents WO-A-00/56629, EP-A-512 470, US-A-5 897 899 or WO-A- 99/03753. These packageing devices are generally airtight, watertight and/or lightproof.

According to a specific embodiment, the housing is delimited by two sealed sheets. According to another embodiment, the housing is delimited by a container closed by a lid. These devices can be manufactured from woven or nonwoven materials made of plastic, of plant material, for example of cellulose, of metal, such as aluminium, or of composite. Such devices are described, for example, in the documents WO-A-00/56629 , EP-A-512 470, US-A-5 897 899 or WO-A- 99/03753.

The plant substances which can be used according to the invention can be obtained from wood, leaves, grasses, flowers, fruits, roots, bark, pulp, peel, berries, pods and seeds of plants. They can be obtained, for example, from fruits (apple, kiwi fruit, blackcurrant, cherries) , including citrus fruits (lemon, orange, grapefruit) , leaves (green tea) , flowers (camomile) and any plant or any tree.

Mention may in particular be made, as examples of plant substances, of: - for their softening properties: apricot, cornflower, Aaron's rod, camomile, mayweed, field poppy, fenugreek, Althaea, flax, lily, mallow, marigold, elder, linden, coltsfoot, psyllium, plantain, quince, peach, orange, cactus or apple,- - for their anti- inflammatory properties: agrimony, hawthorn, heather, couch grass, juniper, Althaea, elder, linden, fenugreek, gentian, lettuce, wild pansy, plantain, blackberry, rosemary, sage, black bryony, coltsfoot, everlasting or daisy; - for their antipruritic properties: lady's mantle, lavender, walnut, plantain, scabious, cabbage, chervil, clematis, cucumber, comfrey, birthwort, burdock, Aaron's rod, camomile, eyebright or English ivy; - for their antiseptic properties: garlic, agrimony, bilberry, burdock, oak, comfrey, eucalyptus, juniper, rose geranium, laurel, lavender, marjoram, mint, pine, rosemary, sandalwood, mother-of- thyme, thyme, sage, honeysuckle, everlasting, daisy or tansy; for their antiperspirant properties: sage, oak, walnut, pine, horsetail or coltsfoot; for their astringent properties: acacia, common yarrow, agrimony, lady's mantle, madrone, mugwort, comfrey, cypress, oak, wild rose, witch hazel, black mulberry, bilberry, hazel, walnut, nettle, poplar, plantain, blackberry, rhatany, rose, common loosestrife, willow, tormentil, cat grape or melilot; for their soothing properties: carrot, wild pansy, elder, linden, passionflower, basil, camphor, pear, apple, vine grape, lettuce, rose or ginger; - for their healing properties:

St. John's wort, silverweed cinquefoil, marigold, mayweed, camomile, comfrey, common yarrow, wormwood, agrimony, mugwort, arnica, chervil, bilberry, periwinkle, plantain, poplar, primrose, sage, groundsel, elder, vervain, angelica, birthwort, alder, southernwood, bistort, birch, blessed thistle, juniper, medlar, eucalyptus, kidney vetch, avens, centaurea, cabbage, houseleek, strawberry, horsetail, meadowsweet, coltsfoot, wild pansy, burdock, daisy or lily; - for their stimulating properties:

St. John's wort, eglantine, mistletoe, mate, sweet acacia, wormwood, arnica, calamint, cinnamon, geranium, hyssop, marjoram, balm, parsley, Scotch pine, rosemary, savory, mother-of-thyme, basil, wild rose, gentian, hop, white laurel, mint, sage, tormentil, common yarrow, agrimony, avens, bistort, oak, quince, cypress, horse chestnut, medlar, walnut, nettle, plantain, leek, cinquefoil, knotweed, common loosestrife, speedwell, angelica, mugwort, woodruff, juniper, mustard, cinchona, fumitory, nasturtium, cress, rockweed, butcher's broom or tansy; for their properties promoting the support of the blood and lymphatic microcirculation: blackcurrant, bilberry and grape seeds,- for their texturing properties: wheat or fucus,- for their antioxidant properties: rice, rosemary, sage, thyme, green tea or liquorice; - for their foaming or emulsifying properties: soapwort, ivy, butcher's broom, panama wood, soapbark, sarsaparilla, quinoa, soya or citrus fruits, such as lemon; for their photoprotective properties: aloes, sunflower, liquorice, magnolia or resurrection lily; for their thickening or absorbent properties: pea, wheat, potato or maize,- and for their odorous properties: rosemary, violet, lavender and rose.

More particularly, the plant substances used in the process according to the present invention are those comprising polyphenols and oligomers of the categories of flavonoids, such as: substances comprising flavonols and flavonol oligomers, which are, for example, in lemon peel; liquorice roots,- grape and blackcurrant seeds,- green tea leaves; pine bark; hawthorn berries,- cocoa pods and beans,- substances comprising flavones, which are, for example, in camomile leaves and skullcap root; substances comprising flavans, which are, for example, in flower petals (cotton, and the like) ; - substances comprising isoflavones, which are, for example, in soya germ; substances comprising flavanones, which are, for example, in pine bark or citrus fruit peel (orange, lemon, and the like) ; - substances comprising chalcones, which are, for example, in citrus fruit peel and apple peel; substances comprising arylchromans, which are, for example, in logwood and brazilwood; substances comprising anthocyanidins, which are, for example, in sorghum seeds and leaves or cocoa pods and beans ; substances comprising coumarin derivatives, which are, for example, Skimmia japonica bark; - and their mixtures.

The plant substance or substances can be employed as a mixture with one or more solid or pasty and preferably pulverulent adjuvants. Once the percolation is complete, these adjuvants generally remain in the percolator but they may also be found in the plant extract obtained after percolation. The adjuvants can be chosen from clays, salts, anionic, cationic, nonionic, amphoteric or zwitterionic surface-active agents, natural or synthetic thickeners, glass beads, silica, nylon, waxes, pigments, alumina, titanium dioxide, zeolites, poly(methyl methacrylate) (PMMA), chitosan, maltodextrin, cyclodextrin, mono- or disaccharides, such as glucose, sucrose, sorbitol or fructose, zinc oxide, zirconium oxide, particles of resin, such as silicone or silica beads, talc, polyaspartic acid, borosilicates, in particular calcium borosilicate, polyethylene, cotton, polytetrafluoro- ethylene (PTFE) , cellulose and its derivatives, superabsorbent compounds, magnesium or calcium carbonates, optionally modified starch, maize seeds, polydimethylsiloxane gums, polyacrylamide, porous hydroxyapatite, silk, collagen, sawdust, fucus powder, flours or extracts of wheat, rice, pea, lupin, soya or barley, crosslinked polyvinylpyrrolidone, calcium alginate, active charcoal, poly (vinylidene chloride/acrylonitrile) particles, in particular those sold under the general name Expancel by Akzo Nobel, and their mixtures.

When one or more adjuvants are present, the plant substance or substances are preferably present in an amount ranging from 0.5 to 99% by weight, better still from 1 to 80% by weight and more preferably still from 2 to 60% by weight, with respect to the total weight of plant substances and adjuvants.

The topical composition obtained according to the process of the invention comprises, in addition to the plant extract or extracts and the component (s) of the fluid, namely water and/or the physiologically acceptable solvent (s), optionally all or a portion of the adjuvant or adjuvants presents in the solid or pasty mixture and the preparation comprising at least one hydrolysable hydrophilic compound. This composition can advantageously be devoid of preservatives.

The amount of plant extract (s) obtained in stage (1) in the final composition obtained by the process of the present invention can range, for example, from 1 x 10^"3 to 99% by weight, preferably from 1 x 10^"2 to 50% by weight and more preferably still from 0.05 to 30% by weight, with respect to the total weight of the composition.

The preparation A to which will be added the plant extract obtained by percolation can have any of the formulation forms generally used in the cosmetics field.

Thus, the preparations according to the invention can, for example, be provided in the form of aqueous or aqueous/alcoholic solutions, of oil-in-water (0/W) or water-in-oil (W/0) or multiple (triple: W/O/W or 0/W/O) emulsions, of aqueous gels, of dehydrated anhydrous products or of dispersions of an oily phase in an aqueous phase using spherules, it being possible for these spherules to be polymeric nanoparticles, such as nanospheres and nanocapsules, or lipid vesicles of ionic type (liposomes) and/or nonionic type. These preparations are prepared according to standard methods. In addition, they can be more or less fluid and have the appearance, for example, of a white or coloured cream, of a milk, of a lotion, of a serum, of a film or of a powder.

This preparation comprises at least one hydrolysable hydrophilic compound. The term "hydrolysable hydrophilic compound" is understood to mean a compound which is soluble in water and which is sensitive to hydrolysis, that is to say which can be cleaved by hydrolysis. These compounds are chosen from nucleosides and glucosides, preferably of vegetable origin, which are sugar ethers, esters or amines. Mention may be made, for example, as hydrolysable hydrophilic compounds chosen from nucleosides and glucosides, of the glucosylated derivative of vitamin C or glucopyranosyl-1 -ascorbic acid (INCI name: ascorbyl glucoside) (sugar ether) , adenosine (sugar amine) , rutin (quercetin sugar derivative) , isoquercitrin, and their mixtures.

The amount of hydrolysable hydrophilic compound (s) in the preparation A can vary to a large extent and can range, for example, from 0.0001 to 50% by weight and preferably from 0.005 to 20% by weight, with respect to the total weight of the preparation. In the final composition, this amount can range, for example, from 0.001 to 10% by weight and preferably from 0.005 to 5% by weight, with respect to the total weight of the composition.

When the preparation comprises an oily phase, the latter preferably comprises at least one oil, in particular one physiologically acceptable oil. It can additionally comprise other fatty substances.

Mention may be made, as oils which can be used in the composition of the invention, for example, of: hydrocarbon oils of animal origin, such as perhydrosqualene ; hydrocarbon oils of vegetable origin, such as liquid triglycerides of fatty acids comprising from 4 to 10 carbon atoms, such as triglycerides of heptanoic acid or octanoic acid, or also, for example, sunflower, maize, soybean, cucumber, grape seed, sesame, hazelnut, apricot, macadamia, arara, castor or avocado oils, triglycerides of caprylic/capric acids, such as those sold by Stearineries Dubois or those sold under the names Miglyol 810, 812 and 818 by Dynamit Nobel, jojoba oil or shea butter oil; synthetic esters and ethers, in particular of fatty acids, such as oils of formulae R¹COOR² and R¹OR² in which R¹ represent the residue of a fatty acid comprising from 8 to 29 carbon atoms and R² represents a linear or branched hydrocarbon chain comprising from 3 to 30 carbon atoms, such as, for example, Purcellin oil, isononyl isononanoate, isopropyl myristate, 2- ethylhexyl palmitate, 2-octyldodecyl stearate, 2- octyldodecyl erucate or isostearyl isostearate,- hydroxylated esters, such as isostearyl lactate, octyl hydroxystearate, octyldodecyl hydroxystearate, diisostearyl malate, triisocetyl citrate or heptanoates, octanoates or decanoates of fatty alcohols; polyol esters, such as propylene glycol dioctanoate, neopentyl glycol diheptanoate and diethylene glycol diisononanoate; and pentaerythritol esters, such as pentaerythrityl tetraisostearate,- linear or branched hydrocarbons of mineral or synthetic origin, such as volatile or nonvolatile liquid paraffins and their derivatives, liquid petrolatum, polydecenes or hydrogenated polyisobutene, such as Parleam oil; fatty alcohols having from 8 to 26 carbon atoms, such as cetyl alcohol, stearyl alcohol and their mixture (cetearyl alcohol), octyldodecanol , 2-butyloctanol, 2-hexyldecanol , 2-undecylpentadecanol , oleyl alcohol or linoleyl alcohol; fluorinated oils which partially comprise hydrocarbon and/or silicone, such as those described in the document JP-A-2-295912 ; silicone oils, such as volatile or nonvolatile polymethylsiloxanes (PDMSs) comprising a linear or cyclic silicone chain which are liquid or pasty at ambient temperature, in particular cyclopolydimethylsiloxanes (cyclomethicones) , such as cyclohexasiloxane; polydimethylsiloxanes comprising pendent alkyl, alkoxy or phenyl groups or alkyl, alkoxy or phenyl groups at the end of the silicone chain, which groups have from 2 to 24 carbon atoms,- phenylated silicones, such as phenyl trimethicones, phenyl dimethicones, phenyl (trimethylsiloxy) diphenylsiloxanes, diphenyl dimethicones, diphenyl (methyldiphenyl) - trisiloxanes, (2-phenylethyl) trimethylsiloxysilicates and polymethylphenylsiloxanes ; their mixtures.

The term "hydrocarbon oil" is understood to mean, in the list of the oils mentioned above, any oil comprising predominantly carbon and hydrogen atoms and optionally ester, ether, fluorinated, carboxylic acid and/or alcohol groups .

The other fatty substances which can be present in the oily phase are, for example, fatty acids comprising from 8 to 30 carbon atoms, such as stearic acid, lauric acid, palmitic acid and oleic acid; waxes, such as lanolin, beeswax, carnauba wax, candililla wax, paraffin or lignite waxes or microcrystalline waxes, ceresin or ozokerite, synthetic waxes, such as polyethylene waxes or Fischer-Tropsch waxes,- silicone resins, such as trifluoromethyl Cl -4 alkyl dimethicone and trifluoropropyl dimethicone; and silicone elastomers, such as the products sold under the "KSG" names by Shin-Etsu, under the "Trefil", "BY29" or "EPSX" names by Dow Corning or under the "Gransil" names by Grant Industries . These fatty substances can be chosen in a way varied by a person skilled in the art in order to prepare a composition having the properties, for example of consistency or of texture, desired.

The emulsions generally comprise at least one emulsifier chosen from amphoteric, anionic, cationic or nonionic emulsifiers, used alone or as a mixture. The emulsifiers are appropriately chosen according to the continuous phase of the emulsion to be obtained (W/0 or 0/W) . When the emulsion is a multiple emulsion, it generally comprises an emulsifier in the primary emulsion and an emulsifier in the external phase into which the primary emulsion is introduced.

Mention may be made, as emulsifiers which can be used in the preparation of the W/0 emulsions, for example, of sorbitan, glycerol or sugar alkyl esters or ethers,- silicone surfactants, such as dimethicone copolyols, for example the mixture of cyclomethicone and of dimethicone copolyol sold under the names DC 5225 C and DC 3225 C by Dow Corning, and such as alkyl dimethicone copolyols, for example the lauryl dimethicone copolyol sold under the name "Dow Corning 5200 Formulation Aid" by Dow Corning, the cetyl dimethicone copolyol sold under the name Abil EM 90 by Goldschmidt and the polyglyceryl-4 isostearate/cetyl dimethicone copolyol/hexyl laurate mixture sold under the name Abil WE 09⁰ by Goldschmidt. It is also possible to add thereto one or more coemulsifiers which can advantageously be chosen from the group consisting of branched-chain fatty acid and polyol esters and in particular branched-chain fatty acid and glycerol and/or sorbitan esters, for example polyglyceryl isostearate, such as the product sold under the name Isolan GI 34 by Goldschmidt, sorbitan isostearate, such as the product sold under the name Arlacel 987 by ICI, and sorbitan glyceryl isostearate, such as the product sold under the name Arlacel 986 by ICI, and their mixtures .

Mention may be made, as emulsifiers which can be used in the preparation of the 0/W emulsions, for example, of nonionic emulsifiers, such as esters of fatty acids and of oxyalkylene (more particularly polyoxyethylene) polyols, for example polyethylene glycol stearates, such as PEG-100 stearate, PEG-50 stearate and PEG-40 stearate; and their mixtures, such as the mixture of glyceryl monostearate and of polyethylene glycol (100 EO) stearate sold under the name Simulsol 165 by Seppic,- oxyalkylenated esters of fatty acids and of sorbitan comprising, for example, from 20 to 100 EO units, for example those sold under the trade names Tween 20 or Tween 60 by Uniqema,- oxyalkylenated (oxyethylenated and/or oxypropylenated) ethers of fatty alcohols; sugar esters, such as sucrose stearate; and their mixtures, such as, for example, the mixture of glyceryl stearate and of PEG-100 stearate sold under the name Arlacel 165 by Uniqema.

Coemulsifiers can be added to these emulsifiers, such as, for example, fatty alcohols having from 8 to 26 carbon atoms, such as cetyl alcohol, stearyl alcohol and their mixture (cetearyl alcohol) , octyldodecanol , 2-butyloctanol , 2-hexyldecanol , 2-undecylpentadecanol or oleyl alcohol .

It is also possible to prepare emulsions devoid of emulsifying surfactants or comprising less than 0.5% of the total weight of the composition thereof by using appropriate compounds, for example polymers having emulsifying properties, such as the polymers sold under the names Carbopol 1342 and Pemulen by Noveon; or polymers and copolymers of 2-acrylamido-2- methylpropanesulphonic acid which are optionally crosslinked and/or neutralized, such as the poly (2-acrylamido-2-methylpropanesulphonic acid) sold by Clariant under the name "Hostacerin AMPS" (CTFA name: ammonium polyacryldimethyltauramide) or such as the polymer emulsified sold under the name Sepigel 305 by Seppic (INCI name: Polyacrylamide/C13-C14 Isoparaffin/Laureth-7) ; particles formed of ionic or nonionic polymers, more particularly particles formed of anionic polymer, such as in particular polymers of isophthalic acid or of sulphoisophthalic acid, in particular the phthalate/sulphoisophthalate/glycol copolymers (for example diethylene glycol/phthalate/isophthalate/1 , 4 -cyclohexanedimethanol

(INCI name: Diglycol/CHDM/Isophthalates/SIP copolymer)) sold under the names Eastman AQ polymer (AQ35S, AQ38S,

AQ55S, AQ48 Ultra) by Eastman Chemical. It is also possible to prepare emulsions devoid of emulsifiers which are stabilized by silicone particles or particles of metal oxide, such as TiO₂, or others.

In a known way, the preparation used in the process of the invention can also comprise adjuvants Standard in the cosmetics or dermatological field, such as active principles, hydrophilic or lipophilic gelling agents, hydrophilic or lipophilic active principles, preservatives (for example, phenoxyethanol and parabens) , antioxidants, solvents, fragrances, fillers, UV screening agents, bactericides, odour absorbers, colouring materials, salts, a UV-A and/or UV-B screening agent (organic or inorganic) or surfactants. The amount of these various adjuvants are those conventionally used in the field under consideration, for example from 0.01 to 20% of the total weight of the composition. These adjuvants, depending on their nature, can be introduced into the fatty phase, into the aqueous phase and/or into the lipid spherules.

The preparation generally comprises water and it can also comprise one or more organic solvents. Mention may be made, as organic solvent, for example, of Ci-C₄ monoalcohols, such as ethanol and isopropanol ; polyols and polyol ethers, such as 2-butoxyethanol , propylene glycol, propylene glycol monomethyl ether, diethylene glycol monoethyl ether and diethylene glycol monomethyl ether, and their mixtures. These solvents can be present in proportions preferably of, for example, between 1 and 40% by weight, with respect to the total weight of the final composition, preferably between 2 and 30% by weight and better still between 2 and 15% by weight, with respect to the total weight of the preparation.

The preparations can also comprise, as active principles other than the hydrolysable hydrophilic compound or compounds, for example, antiageing/antiwrinkle agents, such as antiglycation agents, agents which stimulate the synthesis of dermal or epidermal macromolecules and/or which prevent their decomposition, agents which stimulate the proliferation of fibroblasts and/or keratinocytes or which stimulate the differentiation of keratinocytes, muscle relaxants, and the like,- moisturizing agents,- desquamating agents,- agents for combating pollution and free radicals; slimming agents,- agents which act on the microcirculation; agents which act on the energy metabolism of the cells,- tightening agents,- antiacne agents; anti- inflammatory agents/agents for combating irritation. They can comprise in particular α-hydroxy acids and/or β-hydroxy acids.

Mention may be made, by way of illustration and without limitation, of the following families (the names correspond to the CTFA nomenclature for screening agents) : anthranilates, in particular menthyl anthranilate,- benzophenones, in particular benzophenone-1 , benzo- phenone-3, benzophenone-5 , benzophenone-6 , benzo- phenone-8, benzophenone-9 , benzophenone-12 and preferably benzophenone-2 (oxybenzone) or benzophenone- 4 (Uvinul MS40, available from BASF); benzylidene cam- phors, in particular 3-benzylidene camphor, benzylidene camphor sulphonic acid, camphor benzalkonium methosul- phate, polyacrylamidomethyl benzylidene camphor, tere- phthalylidene dicamphor sulphonic acid and preferably 4-methylbenzylidene camphor (Eusolex 6300, available from Merck); benzimidazoles, in particular benzimidazilate (Neo Heliopan AP, available from Haarmann and Reimer) or phenylbenzimidazole sulphonic acid (Eusolex 232, available from Merck); benzotriazoles, in particular drometrizole trisiloxane or methylene bis-benzotriazolyl tetramethylbutylphenol

(Tinosorb M, available from Ciba) ; cinnamates, in particular cinoxate, DEA methoxycinnamate, diisopropyl methyl cinnamate, glyceryl ethylhexanoate dimethoxy- cinnamate, isopropyl methoxycinnamate, isoamyl cinnamate and preferably ethocrylene (Uvinul N35, available from BASF) , octyl methoxycinnamate (Parsol MCX, available from Hoffmann-LaRoche) or octocrylene (Uvinul 539, available from BASF); dibenzoylmethanes, in particular butyl methoxydi- benzoylmethane (Parsol 1789); imidazolines, in particular ethylhexyl dimethoxybenzylidene dioxoimidazoline propionate; PABAs, in particular ethyl dihydroxypropyl PABA, ethylhexyl dimethyl PABA, glyceryl PABA, PABA, PEG-25 PABA and preferably diethylhexyl butamido triazone (Uvasorb HEB, available from 3V Sigma) , ethylhexyl triazone (Uvinul T150, available from BASF) or ethyl PABA (benzocaine) ; salicylates, in particular dipropylene glycol salicylate, ethylhexyl salicylate, homosalate or TEA salicylate; triazines, in particular anisotriazine (Tinosorb S, available from Ciba); zinc oxide and titanium dioxide.

The amount of screening agents depends on the final use desired. It can range, for example, from 1 to 20% by weight and better still from 2 to 10% by weight, with respect to the total weight of the composition. Of course, a person skilled in the art will take care to choose this or these optional additives so that the advantageous properties intrinsically attached to the cosmetic composition in accordance with the invention are not, or not substantially, detrimentally affected by the envisaged addition or additions.

The final composition obtained by the process of the invention is generally provided in a form which depends on that of the preparation with which the plant extract obtained by percolation is mixed. It preferably has a pH of between 3 and 8, it being possible for this pH to be adjusted to the desired value using acidifying or basifying agents generally used in cosmetics or alternatively using conventional buffering systems.

The composition obtained by the process according to the invention can constitute in particular a skin care product which can, for example, have a nourishing effect, a moisturizing effect, an antiwrinkle effect, a cleaning effect (combating bacterial adhesion) , an antidesiccating effect or any other skin care application. The final composition can also constitute a make-up product and in particular a foundation for colouring the skin and/or protecting it while contributing a care effect.

The present invention also relates to a method for the cosmetic treatment of the skin comprising the preparation of a cosmetic treatment composition according to the process as defined above and its application to the skin. This application can be carried out, for example, via an operator or via a device not requiring human intervention. The application time can vary between 15 seconds and 1 hour.

The device of the invention can be the subject of a cosmetic kit comprising (1) one or more receptacles suitable for percolation under pressure by the fluid route, the receptacle or receptacles delimiting at least one housing comprising at least one plant substance in the solid or pasty form, and (2) a preparation A comprising at least one hydrolysable hydrophilic compound.

Thus, a further subject-matter of the invention is a cosmetic kit comprising one or more single-dose packageing devices comprising at least one plant substance in the solid or pasty form and a preparation A comprising at least one hydrolysable hydrophilic compound .

The examples below are intended to illustrate the present invention.

Example 1

A capsule comprising 5 g of beech buds is placed in a commercial expresso machine. The steam produced by the machine subsequently passes through this pulverulent mixture until an extract exhibiting a final volume of 15 ml is obtained. The extract is collected in the antiageing emulsion indicated below, comprising 0.05% by weight of adenosine.

Emulsion:

Phase A:

Hydrogenated polyisobutene 5.5 g Isostearyl neopentanoate 3.5 g

PEG-20 stearate 1 g

Glyceryl stearate and PEG-100 stearate (Arlacel 165) 2 g

Cetyl alcohol 0.5 g Stearyl alcohol 0.5 g

Stearic acid 1 g

Phase A'

Cyclomethicone 11 g Phase B :

Triethanolamine 0.03 g

Water 53.92 g Adenosine 0.05 g

Phase C:

Sepigel 305 1 g

Parelastyl 5 g

Procedure for the preparation of the emulsion: The phase A was heated with stirring until homogeneous. After cooling, the phase A' was added. The phase B was heated with stirring and then the phase B was poured into the phase A, still with stirring. After cooling to 5O⁰C, the phase C was incorporated in the emulsion. A cream was obtained.

The product obtained by mixing the extract and the emulsion is provided in the form of a cream and it can be applied to the skin while retaining the biological activity of the active principle present and the stability of this active principle in the emulsion. It is suitable for softening and treating wrinkles and fine lines of the skin.

Example 2

Steam is passed, according to the same procedure as that of Example 1, over a capsule comprising 3 g of blackcurrant berry powder, until an extract exhibiting a final volume of 20 ml is obtained. The aqueous extract obtained is collected in a beaker comprising the dry carrier indicated below, comprising 5% by weight of glucopyranosyl-1 -ascorbic acid, the dry carrier dissolving on contact with the extract.

Skin care powder

- Modified starch (C* Flo 06205) 35 g - Silicone oil (phenyl trimethicone, sold under the name DC 556 Fluid by Dow Corning) 60 g

- Glucopyranosyl-1 -ascorbic acid 5 g

A composition is thus obtained which is ready to be applied to the skin and to give radiance to the complexion of the skin.

Example 3

The capsule comprising 4 g of cocoa pods is placed in a commercial expresso machine. The steam produced by the machine subsequently passes through this pulverulent mixture until an extract exhibiting a final volume of 15 ml is obtained. The extract is collected in the thermogelling solution indicated below.

Sodium polyacrylate (450 000 g/mol) carrying Jeffamine M-2005 grafts (random copolymer of ethylene oxide

(6) and of propylene oxide (39)) with a molar grafting level = 3.9% 6 g

Glycerol 5 g

Rutin 2 g EDTA 0.05 g

Demineralized water 71.95 g

After mixing the extract and the film, a gel is obtained, the colour of which is not modified during the cooling thereof.

It is possible, after topical application of the gel, to use a spray system comprising a mineral water rich in bicarbonate and manganese in order to gradually obtain a healthly appearance effect.

Claims

1. Process for the preparation of a cosmetic or dermatological composition, characterized in that it comprises (1) a stage of percolation of fluid under pressure through at least one plant substance in the solid or pasty form and (2) the incorporation of the plant extract obtained in stage (1) in a preparation A comprising at least one hydrolysable hydrophilic compound chosen from nucleosides and glucosides.

2. Process according to Claim 1, characterized in that the fluid is composed of steam, optionally accompanied by liquid water, or of one or more physiologically acceptable liquid and/or gaseous solvents or also of a mixture of steam, optionally accompanied by liquid water, and of one or more physiologically acceptable liquid and/or gaseous solvents .

3. Process according to Claim 1 or 2 , characterized in that the fluid comprises at least steam.

4. Process according to Claim 1 or 2 , characterized in that the pressure is at least 3 bar and preferably at least 4 bar.

5. Process according to any one of the preceding claims, characterized in that the temperature is at least equal to 3O⁰C.

6. Process according to any one of the preceding claims, characterized in that the plant substance is chosen from plant substances exhibiting softening properties, anti- inflammatory properties, antipruritic properties, antiseptic properties, antiperspirant properties, soothing properties, healing properties, stimulating properties, properties promoting the support of the blood and lymphatic microcirculation, texturing properties, antioxidant properties, foaming or emulsifying properties, photoprotective properties, thickening or absorbent properties, and/or odorous properties.

7. Process according to any one of the preceding claims, characterized in that the plant substance is chosen from those comprising polyphenols and oligomers of the categories of flavonoids.

8. Process according to any one of the preceding claims, characterized in that the plant substance is chosen from lemon peel; liquorice roots,- grape and blackcurrant seeds,- green tea leaves,- pine bark; hawthorn berries,- cocoa pods and beans,- camomile flowers,- skullcap root; flower petals,- soya germ,- citrus fruit peel; apple peel; logwood; brazilwood; sorghum seeds and leaves,- Skimmia japonica bark, and their mixtures.

9. Process according to any one of the preceding claims, characterized in that the plant substance is employed as a mixture with one or more solid or pasty adjuvants.

10. Process according to the preceding claim, characterized in that the plant substance or substances are present in an amount ranging from

0.5 to 99% by weight, with respect to the total weight of plant substances and adjuvants.

11. Process according to any one of the preceding claims, characterized in that the amount of plant extract (s) ranges from 1 x 10^"3 to 99% by weight, with respect to the total weight of the composition.

12. Process according to any one of the preceding claims, characterized in that the hydrolysable hydrophilic compounds are chosen from glucopyranosyl-1 -ascorbic acid, adenosine, rutin, isoquercitrin, and their mixtures.

13. Process according to any one of the preceding claims, characterized in that the hydrolysable hydrophilic compounds are present in an amount ranging from 0.001 to 10% by weight and preferably from 0.005 to 5% by weight, with respect to the total weight of the composition.

14. Cosmetic treatment composition capable of being obtained by the process according to any one of the preceding claims.

15. Composition according to the preceding claim, characterized in that it is devoid of preservative.

16. Cosmetic use of the composition obtained by the process according to any one of Claims 1 to 13 for the cosmetic treatment of keratinous substances.

17. Method for the cosmetic treatment of the skin, characterized in that a cosmetic composition is prepared according to the process defined according to any one of Claims 1 to 13 and in that this composition is applied to the skin.

18. Cosmetic kit comprising (1) one or more receptacles suitable for percolation under pressure by the fluid route, the receptacle or receptacles delimiting at least one housing comprising at least one plant substance in the solid or pasty form, and (2) a preparation A comprising at least one hydrolysable hydrophilic compound chosen from nucleosides and glucosides.