WO2008034700A1

WO2008034700A1 - Process for the preparation of a cosmetic composition having a lightening effect on the skin

Info

Publication number: WO2008034700A1
Application number: PCT/EP2007/059008
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

A subject-matter of the invention is a process for the preparation of a composition for topical application, characterized in that it comprises a stage of percolation of fluid under pressure through at least one plant substance in the solid or pasty form chosen from plant substances comprising coumarin sugar derivatives. Plant substances comprising vitamin C can also be combined therewith. The invention also relates to the composition obtained and to its use in the cosmetics field, in particular for lightening the skin.

Description

Process for the preparation of a cosmetic composition having a lightening effect on the skin

A subject-matter of the present invention is a process for the preparation of a composition for topical application comprising plant substances which are precursors of lightening compounds. A further subject- matter of the invention is the composition obtained and its use in the treatment of keratinous substances, in particular human skin and keratinous fibres, such as the hair.

More particularly, the compositions under consideration according to the invention can constitute a product for the care of the skin and in particular of the face having lightening properties.

It is known that, during the ageing process, various signs highly characteristic of this ageing appear on human skin, being reflected in particular by a modification in the cutaneous function and structure. The main clinical signs of cutaneous ageing are in particular the appearance of fine lines and then of deep wrinkles, which increase with age, and the disruption of the "grain" of the skin, that is to say that the microrelief is less uniform and exhibits an anisotropic nature.

In addition, the complexion of the skin is generally modified; it appears paler and yellower, which appears to be due essentially to a disruption of the microcirculation (less haemoglobin in the dermal papillae) . In addition, coloured blemishes appear at the surface, which is due to a detrimental change in melanogenesis .

Furthermore, some people with coloured, indeed even dark, skins are looking for cosmetic compositions which make it possible to lighten the skin. To obtain this effect, use is generally made of cosmetic or dermatological compositions comprising one or more lightening agents. However, in order to obtain a significant lightening effect, these compositions have to, on the one hand, comprise high amounts of lightening agents and, on the other hand, be used for a prolonged period of time. This is because, in the majority of cases, an immediate lightening effect is not observed upon application of the compositions comprising the said lightening agents. Mention may in particular be made, by way of representation of the lightening agents commonly used, of agents with an optical effect and in particular optical brightening agents. Such agents have the ability to induce, under appropriate conditions of use, a modification in the visual appearance of the surface on which they are applied. However, optical brighteners are difficult to synthesize.

The use of vitamin C (ascorbic acid) is also known. However, this compound presents problems of instability, resulting in particular in the appearance of colour in the composition comprising it, and it is necessary to stabilize the vitamin C in order to have cosmetically acceptable compositions, that is to say exhibiting neither colour nor odour nor instability.

The need thus remains to have available lightening cosmetic compositions which do not emit colour in a UV medium or in a visible medium and which, once applied to the skin, give a specific radiance to the complexion.

The Applicant Company has discovered, surprisingly, that, by using a process for the percolation of specific plant substances, it is possible to obtain bioconvertible compounds which, when applied to the skin, are converted by the enzymes of the skin to compounds having lightening properties. The process according to the invention makes it possible to obtain concentrated aqueous plant extracts which give an effect of radiance to the complexion.

The invention thus relates to a process for the preparation of a composition for topical application, characterized in that it comprises a stage of percolation of fluid under pressure through one or more plant substances in the solid or pasty form, at least one plant substance being chosen from plant substances comprising coumarin sugar derivatives.

The term "plant substance" is understood to mean any substance belonging to the plant field (trees, plants, leaves, flowers) . Thus, the plant substance can come from wood, leaves, grasses, flowers, fruits, roots, bark, pulp, peel, berries, beans and seeds of plants.

The term "coumarin sugar derivatives" is understood to mean coumarin derivatives comprising a sugar, in particular a glycoside unit, such as a glucosyl or a glucopyranosyl , which compounds will lighten the complexion of the skin. They are generally hydroxylated coumarin derivatives comprising a glucoside unit, such as, for example, esculoside (or esculin or dihydroxycoumarin glucoside) , which is obtained from leaves and bark of the horse chestnut.

The extracts obtained after percolation from the plant substances of the coumarin sugar derivatives are aqueous extracts having specific properties as, after application to the skin, they become fluorescent and they will give a radiance to the complexion, the effect obtained being much greater than when the coumarin derivatives are applied directly to the skin without a percolation stage.

According to a specific embodiment of the invention, it is possible to combine the plant substance comprising coumarin sugar derivatives with one or more plant substances comprising vitamin C.

The term "plant substance comprising vitamin C" is understood to mean a plant naturally rich in vitamin C, that is to say comprising it in an amount sufficient for the vitamin C to be active with regard to the complexion of the skin and to lighten it.

As the composition prepared according to the process of the invention is intended for topical application and in particular for application to keratinous substances, it is physiologically acceptable. The term "physiologically acceptable composition" is understood to mean a composition which is nontoxic, which is capable of being applied to keratinous substances and which is pleasant to use. The term "keratinous substances" is understood to mean the skin, scalp, lips and/or superficial body growths, such as the nails, eyelashes, eyebrows and hair. The composition can in particular be a cosmetic or dermatological composition.

The percolation stage makes it possible to obtain a plant extract and the composition can be composed of the extract as obtained by the claimed process or it can comprise the extract and a physiologically acceptable medium comprising or not comprising other compounds commonly used in the cosmetics field.

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 for lightening the skin.

Finally, a subject-matter of the invention is a packaging device which makes it possible to carry out the preparation process of the present invention. Other subject-matters, characteristics, aspects and advantages of the invention will become even more clearly apparent on reading the description and examples which follow.

Percolation process

The percolation process is carried out according to the usual percolation technique. A fluid, 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, under a pressure preferably of at least 3 bar

(3 x 10⁵ Pa) , 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.

This process results in the production of a stable ready-for-use plant extract intended to be used rapidly after it has been produced, for example in the following 5 minutes after it has been produced, in particular after cooling to a cosmetically acceptable temperature, preferably of less than 6O⁰C. This extract can be used up to one week after it has been produced.

Given the very short preparation time, the plant extracts obtained by the process described above and the cosmetic compositions comprising them 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 substances 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 makes the process particularly economic and safer for the user.

Percolation is a movement of fluid through a saturated porous medium which allows the fluid to pass, under the action or the effect of pressure.

The fluid can be composed of steam, optionally accompanied by liquid water, or of one or more physiologically acceptable liquid and/or gaseous solvents, in particular organic 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, and also aromatic alcohols, such as benzyl alcohol or phenoxyethanol , and their mixtures.

The percolation fluid can also be a mineral water, such as, for example, waters from Vichy (springs of Lucas, Hδpital or Grande Grille) , water from La Roche-Posay, water from Avene or water from Vittel . One or more solvents can also be added thereto, as indicated above.

The process of the present invention can be carried out starting from a conventional device which makes it possible to generate a fluid under pressure, at a temperature preferably of 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 the percolation fluid as described above.

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 greater than 3O⁰C, preferably between 3O⁰C and 15O⁰C, under a pressure preferably of at least 3 bar, better still of at least 4 bar and preferably of at least 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 packaging 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 packaging 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.

Another subject-matter of the invention is a receptacle, in particular in the form of a bag or of a capsule, suitable for percolation under pressure by the fluid route, the receptacle delimiting at least one housing comprising at least one plant substance in the solid or pasty form chosen from plant substances comprising coumarin sugar derivatives and in particular from the bark of Skimmia japonica, the leaves and bark of the horse chestnut (Aesculus hippocastanum) , and their mixtures.

As indicated above, the housing can be delimited by two sealed sheets or it can be delimited by a container closed by a lid.

The process described above may comprise only the percolation stage but it may also comprise one or more subsequent stages of mixing with a physiologically acceptable medium and/or with one or more additives used in cosmetics.

Plant substance

Use may be made, to prepare the plant extract, of any plant substance comprising a coumarin sugar derivative, this substance being 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 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.

Mention may be made, as plant substances comprising coumarin sugar derivatives, of the substances comprising glucoside derivatives of coumarin comprising one or more hydroxyl groups, such as: the bark of Skimmia japonica, which comprises

7-hydroxycoumarin 7 -glucoside (or umbelliferone glucoside) , - the leaves and bark of the horse chestnut, which comprise 6 , 7-dihydroxycoumarin 6 -glucoside, such as the bark of the horse chestnut sold under the name esculin by Merck.

As indicated above, according to a specific embodiment of the invention, it is possible to add, to the plant substances comprising coumarin sugar derivatives, one or more plant substances comprising vitamin C, which can be in the same receptacle or in a separate receptacle. Mention may be made, as plant substances comprising vitamin C, of, for example, the fruits of the wild rose (rosehip), broccoli, horseradish or parsley.

In addition to the plant substances comprising a coumarin sugar derivative or vitamin C, there may be one or more other plant substances which can come from wood, leaves, grasses, flowers, fruits, roots, bark, pulp, peel, berries, beans and seeds of plants, such as : 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: 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, marjory, 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: sunflower, liquorice, magnolia or resurrection lily; for their thickening or absorbent properties: pea, wheat 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,- 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 ,- 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 remain in the percolator. 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 substance (s) and adjuvants.

Composition The composition obtained according to the process of the invention comprises the plant extract or extracts obtained by percolation and it can comprise any other adjuvant added during or after the percolation stage.

A plant extract is obtained from the preparation process of the invention which can constitute a composition for the cosmetic treatment of keratinous substances and which can be applied directly to the keratinous substances. Furthermore, this extract can be mixed with a cosmetically acceptable medium optionally comprising one or more additives or active principles conventionally used in cosmetics. It is also possible to mix at least two compositions obtained by the process of the invention.

Depending on whether the process described above comprises only the percolation stage or whether it comprises one or more subsequent stages of mixing the extract obtained with a physiologically acceptable medium, the composition obtained may comprise only the plant extract or it may additionally comprise the additives of the physiologically acceptable medium added after the percolation stage.

The invention also relates to a composition, in particular a cosmetic composition, obtained by the process according to the invention. This composition exhibits the advantage of being able to be devoid of preservatives.

A specific embodiment of the invention consists in applying the composition obtained via a device not requiring human intervention and optionally equipped with a cooling means.

Another subject-matter of the invention is a method for the cosmetic treatment of keratinous substances, characterized in that a cosmetic composition is prepared according to the process as defined above and in that this composition is applied to the keratinous substance. The keratinous substance is preferably the skin.

More especially, a further subject-matter of the invention is a cosmetic method for lightening the skin, which consists in applying, to the skin, a composition obtained by the process according to the invention. The application to keratinous substances 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 amount of plant extract (s) present in the composition obtained by the process of the present invention is generally between 0.01 and 99% by weight, preferably between 0.05 and 50% by weight and more preferably still between 0.1 and 30% by weight, with respect to the total weight of the composition.

When the plant extract obtained by the process of the present invention is mixed with a physiologically acceptable medium, this medium can have different formulation forms and it can, for example, be aqueous or anhydrous or in the form of emulsions and be fluid, creamy or solid.

The aqueous medium comprises water or a mixture of water and of at least one organic solvent to dissolve the compounds which would be insufficiently soluble in water. Mention may be made, as organic solvent, for example, of lower Ci-C₄ alkanols, 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 also aromatic alcohols, such as benzyl alcohol or phenoxyethanol , and their mixtures.

The solvents are preferably present in proportions preferably of between 1 and 40% by weight, with respect to the total weight of the composition, and more preferably still between 5 and 30% by weight.

According to the formulation form desired, this aqueous medium can comprise any additive generally necessary in order to obtain the desired formulation; for example, if it is desired to have an emulsion, fatty substances, such as, for example, oils, and optionally emulsifiers are added.

Mention may be made, as examples of such additives, of anionic, cationic, nonionic, amphoteric or zwitterionic surface-active agents or their mixtures, anionic, cationic, nonionic, amphoteric or zwitterionic polymers or their mixtures, inorganic or organic thickening agents and in particular associative thickeners, antioxidants, penetrating agents, sequestering agents, fragrances, buffers, dispersing agents, conditioning agents, such as, for example, silicone oils, film- forming agents, ceramides, preservatives, opacifying agents, but also oils, waxes, gums, or coloured or pearlescent pigments.

The above additives are generally present in amounts of, for each of them, between 0.01 and 20% by weight, with respect to the weight of the composition.

Of course, a person skilled in the art will take care to choose this or these optional compounds 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 pH of the composition is generally between 3 and 8 and preferably between 4 and 7. It can be adjusted to the desired value using acidifying or basifying agents commonly used in cosmetics or else using conventional buffering systems.

Mention may be made, among acidifying agents, by way of example, of inorganic or organic acids, such as hydrochloric acid, orthophosphoric acid, sulphuric acid, carboxylic acids, such as acetic acid, tartaric acid, citric acid or lactic acid, or sulphonic acids. Mention may be made, among basifying agents, by way of example, of ammonia, alkaline carbonates, alkanolamines, such as mono-, di- and triethanolamine, and their derivatives, sodium hydroxide or potassium hydroxide .

The physiologically acceptable medium can also be anhydrous and, for example, a dry carrier, such as a thin film, as described, for example, in the document EP-A-I 588 694, or an atomized powder, as described, for example, in the document EP-A-938 892, which are powders comprising modified starch and an oily phase, or a pulverulent composition of the "marshmallows" type, as described, for example, in the documents EP-A- 966 956 and EP-A-968 702.

The physiologically acceptable medium can also be an oil-in-water (0/W) or water-in-oil (W/0) or multiple (W/O/W or 0/W/O) emulsion prepared conventionally with or without emulsifier. 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. The emulsions comprise, in the oily phase, at least one oil chosen from the oils generally used in the cosmetics field.

This medium can also comprise one or more active principles chosen from those generally used in the field concerned. Use may in particular be made, as active principles, of vitamins (vitamin A or retinol, vitamin C and vitamin C derivatives, such as esters, vitamin E or tocopherol, vitamin K, vitamin PP or B3 or niacinamide) , alone or as mixtures, and also their derivatives and in particular their esters,- keratolytic and/or desquamating agents, such as β-hydroxy acids, for example salicylic acid and its derivatives, α-hydroxy acids, for example glycolic acid, lactic acid and citric acid, ascorbic acid and its derivatives; anti- inflammatory agents,- soothing agents,- moisturizing agents; matifying agents,- antiacne agents,- and their mixtures .

Depending on the dry carrier used, the final composition can be provided in various forms, such as in the form of liquids, creams or gels or in any other form appropriate for carrying out the treatment of keratinous substances and in particular keratinous fibres and the skin. The composition obtained can constitute in particular a skin care product having, in addition to the lightening effect, a nourishing, moisturizing, antiwrinkle or antidesiccating effect or any other skin care application. It can also constitute a make-up product.

Another embodiment consists in preparing at least two compositions according to the process of the invention, in mixing them, in optionally adding a cosmetically acceptable medium and/or one or more additives conventionally used in cosmetics as described above and in then applying the composition obtained to keratinous substances.

Another subject-matter of the invention is a kit for carrying out the process as defined above, comprising one or more receptacles as defined above and one or more receptacles comprising a physiologically acceptable medium. This kit makes it possible to obtain a composition in accordance with the invention where the percolating extract is added to a physiologically acceptable medium which can be an emulsion, a dry carrier or any other cosmetic formulation form as described above.

The examples below are intended to illustrate the present invention. Example 1 :

A mixture of 3 g of rosehips and 2 g of horse chestnut bark (esculin) is placed in a capsule and the capsule is placed in a commercial expresso machine. The steam produced by the machine subsequently passes through this pulverulent mixture until a composition (A) exhibiting a final volume of 15 ml is obtained. The extract is collected in a moisturizing emulsion which constitutes 80% by weight of the composition.

The moisturizing emulsion has the following composition:

Phase Al Methyl glucose sesquistearate

(Glucate SS) 2%

Stearyl alcohol/ceteareth-20 20%

Preservatives 0.1%

Liquid petrolatum 4% Phase A2

Cyclopentasiloxane 5%

Phase Bl

Glycerol 7% Sodium magnesium silicate (clay) 0.5%

Demineralized water q.s. for 80%

Preservatives 0.25%

Phase B2 PEG-20 methyl glucose sesquistearate

(Glucamate SSE 20) 3%

Demineralized water 19%

Phase C Nylon-12 (Orgasol) 2%

Polyamide (Nylon-66) fibres (Polyamide 0.9 Dtex, 0.3 mm - Paul Bonte) 5% Phase D

Ammonium polyacryloyldimethyltaurate (Hostacerin AMPS from Clariant) 0.2%

Procedure: Phases Al and A2 are heated separately (to approximately 7O⁰C) with stirring and them mixed. Likewise, phases Bl and B2 are heated separately (to approximately 7O⁰C) with stirring and then mixed. The mixture of Bl and B2 is subsequently poured into the mixture of Al and A2 with stirring. Phase C is then added, followed by phase D, and the mixture is homogenized.

20 ml of aqueous extract are added to this composition. An emulsion is then obtained which can be used for the radiance of the complexion.

Example 2 :

Steam is passed over 5 g of Skimmia japonica bark powder according to the same procedure as that of

Example 1. The aqueous extract obtained (15 ml) is collected in a beaker comprising a dry carrier comprising adenosine, which dry carrier dissolves on contact with the extract.

Composition of a dry carrier of anhydrous film type

Hydroxypropylmethylcellulose 10% Glycerol 5% Panthenol 2%

Adenosine 0.15%

Purified water 50%

Procedure for the preparation of the film: all the ingredients are mixed. The mixture is deposited on a silicone paper, using conventional roll or blade coating techniques, with a thickness of the order of 500 μm. After drying in a hot-air circulation tunnel at a temperature of approximately 5O⁰C, the film obtained is cut to the desired shape, for example in the form of square wafers with a side length of 25 mm.

The plant extract obtained after percolation is added to a thin film. A fluid composition is then obtained which can be applied to the skin and which exhibits a significant effect on the radiance of the complexion.

Claims

1. Process for the preparation of a composition for topical application, characterized in that it comprises a stage of percolation of fluid under pressure through one or more plant substances in the solid or pasty form, at least one plant substance being chosen from plant substances comprising coumarin sugar derivatives.

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 that pressure is at least 3 bar and preferably at least 4 bar.

4. Process according to any one of the preceding claims, characterized in that the temperature is greater than 3O⁰C.

5. Process according to any one of the preceding claims, characterized in that the plant substance or substances comprising coumarin sugar derivatives are chosen from the bark of Skimmia japonica, the leaves and bark of the horse chestnut, and their mixtures.

6. Process according to any one of the preceding claims, characterized in that one or more plant substances comprising vitamin C are added to the plant substances comprising coumarin sugar derivatives.

7. Process according to the preceding claim, characterized in that the plant substance or substances comprising vitamin C are rosehips.

8. Process according to any one of the preceding claims, characterized in that the plant substance or substances comprising coumarin sugar derivatives are employed as a mixture with one or more plant substances chosen from substances comprising flavonols and flavonol oligomers, substances comprising flavones, substances comprising flavans, substances comprising isoflavones, substances comprising flavanones, substances comprising chalcones, substances comprising arylchromans, substances comprising anthocyanidins, and their mixtures.

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

10. Process according to any one of the preceding claims, characterized in that it comprises one or more subsequent stages of mixing with a physiologically acceptable medium.

11. Process according to the preceding claim, characterized in that the physiologically acceptable medium is an aqueous medium, an anhydrous medium or an emulsion.

12. Composition capable of being obtained by the process according to any one of the preceding claims.

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

14. Method for the cosmetic treatment of keratinous substances, characterized in that a cosmetic composition is prepared according to the process according to any one of Claims 1 to 11 and in that this composition is applied to the keratinous substance.

15. Cosmetic method for lightening the skin, which consists in applying, to the skin, a composition obtained by the process according to any one of Claims 1 to 11.

16. Receptacle, in particular in the form of a bag or of a capsule, suitable for percolation under pressure by the fluid route, the receptacle delimiting at least one housing comprising at least one plant substance in the solid or pasty form chosen from plant substances comprising coumarin sugar derivatives.

17. Receptacle according to the preceding claim, characterized in that the housing is delimited by two sealed sheets.

18. Receptacle according to Claim 16, characterized in that the housing is delimited by a container closed by a lid.

19. Kit for carrying out the process according to any one of Claims 10 to 14, comprising one or more receptacles according to any one of Claims 16 to 18 and one or more receptacles comprising a physiologically acceptable medium.