WO2013190114A1

WO2013190114A1 - Cosmetic composition comprising non-interference scattering particles and aerogel particles, and cosmetic lightening method

Info

Publication number: WO2013190114A1
Application number: PCT/EP2013/063046
Authority: WO
Inventors: Ludovic Thevenet; Guillaume Cassin
Original assignee: L'oreal
Priority date: 2012-06-21
Filing date: 2013-06-21
Publication date: 2013-12-27
Also published as: CN104379114B; CN104379114A; BR112014027027A2; BR112014027027B8; BR112014027027B1; FR2992197A1; FR2992197B1

Abstract

Cosmetic composition comprising non-interference scattering white particles and aerogel particles, and cosmetic lightening method The subject of the invention is therefore a composition for topical application comprising, in a physiologically acceptable medium, at least one oil, at least hydrophobic silica aerogel particles and at least 0.1% by weight of non-interference scattering white particles characterized by 0.3 µm<D50<40 µm and 1.7<RI<2.2. The invention also relates to a cosmetic method for lightening and/or homogenizing the skin and/or the lips, comprising the topical application of such a composition, and to a makeup method comprising at least one step of applying such a cosmetic composition.

Description

Cosmetic composition comprising non-interference scattering particles and aerogel particles, and cosmetic lightening method The invention relates to a composition for topical application comprising, in a physiologically acceptable medium, at least non-interference scattering particles and at least hydrophobic aerogel particles.

A subject of the invention is also a cosmetic method for lightening and/or homogenizing the skin and/or the lips, comprising the topical application of this composition to the skin or the lips, in particular facial skin and the shadows around the eyes.

It is common for people who have skin which is coloured or who exhibit pigmentary blemishes, rosacea, or shadows around the eyes to want to correct these cutaneous dyschromias and to use, for this purpose, cosmetic or dermatological compositions which make it possible to lighten and to homogenize the complexion. To this end, it is known practice to use cosmetic compositions containing whitening agents.

The substances most commonly used as a whitening agent are hydroquinone and derivatives thereof, kojic acid and derivatives thereof, azelaic acid, arbutin and derivatives thereof, vitamin C and derivatives thereof (for example, magnesium ascorbyl phosphate, or ascorbyl glucoside), alone or in combination with other active agents.

However, it is necessary to use these agents for prolonged periods of time and in high amounts in order to observe a whitening effect on the skin. Furthermore, an immediate effect is not observed upon application of the compositions comprising them. It is known practice to use products containing interference pigments which, although they can conceal skin imperfections, have the major drawback of giving the skin a shiny and not very natural appearance. Furthermore, these pigments have the particularity of giving a nacreous appearance and of strongly colouring the products containing them. It is also known practice to use cosmetic compositions capable of making the complexion uniform and optionally of conferring an immediate white appearance, these compositions being constituted of powders dispersed in a binder. The powders are generally white or coloured pigments depending on the desired effect and/or fillers of different shapes (lamellar, spherical) depending on the desired effect. The complexion is made uniform essentially by virtue of the covering power provided by the pigments and the fillers. The drawback of such compositions is that the softening of the skin defects is provided by the covering power of the compositions. The skin thus made up loses its natural appearance due to the lack of transparency of these compositions.

Finally, it is known practice to use, for the purpose of immediate lightening and homogenizing of the complexion, cosmetic compositions containing fluorescent compounds; optical brighteners, such as stilbene derivatives, coumarin derivatives, oxazole and benzoxazole derivatives and imidazole derivatives, described in applications EP-A-0 962 224 or WO- 00/71085, in particular come to mind. However, there remains a need for cosmetic compositions for topical application which make it possible to obtain an immediate lightening effect, in particular on the complexion, or more generally a correction of dyschromias, in particular a concealer effect, which are not very covering and not very coloured and which do not give the skin a shiny or opaque and artificial appearance. In addition, they are polyvalent and readily suitable for varied types of skin since it is not necessary for the formula to have the exact same shade as the complexion of the individuals.

Surprisingly, it was realized that such an objective could be achieved by introducing, into a cosmetic composition containing at least one oil, the combination of hydrophobic silica aerogel particles and of non-interference scattering white particles characterized by 0.3 μη"ΐ<Ο50<40 μηη and 1 .7<RI<2.2, in particular boron nitride particles.

A subject of the present invention is a cosmetic composition which lightens and homogenizes the skin or the lips, in particular the complexion, and which is characterized by great comfort on application. These compositions contain, in a physiologically acceptable medium containing oil, an effective amount of an aerogel (preferentially of hydrophobic silica) and of boron nitride particles.

The compositions according to the invention can be in the form of a gel, of a serum, of direct, inverse and multiple emulsions, of hot-cast sticks, or of loose or compacted powders.

A subject of the invention is therefore a cosmetic composition which is in particular suitable for topical application to the skin and/or the lips, comprising, in a physiologically acceptable medium, at least one oil, at least 0.1 % by weight of particular non-interference scattering particles relative to the total weight of said composition, and at least hydrophobic aerogel particles.

The compositions according to the invention make it possible to immediately confer on the skin to which they are applied, and in particular on the complexion, improved qualities in terms of uniformity, homogeneity, transparency and whiteness. These compositions can also have concealing properties. These compositions can also lighten the lips.

A subject of the present invention is thus also a cosmetic method intended for immediate lightening and/or homogenizing of the skin and/or of the lips, in particular of the skin.

A subject of the present invention is thus also a use of the combination of at least hydrophobic silica aerogel particles and of at least 0.1 % by weight of non-interference scattering white particles characterized by 0.3 μη"ΐ<Ο50<40 μηη and 1 .7<RI<2.2 in a cosmetic composition for softening skin defects.

The compositions according to the invention can also make it possible to reduce the perception of the skin defects at the surface of the skin, and in particular to mask the wrinkles and pores and/or to camouflage the coloured defects of the skin, namely red blotches or blemishes.

Moreover, the combination of hydrophobic aerogel particles and of non-interference scattering particles makes it possible to obtain compositions which are comfortable and soft on application, and which have matting and soft focus properties.

Non-interference scattering white particles

The term "scattering particles" is intended to mean particles exhibiting light scattering which does not show a favoured direction. Consequently, particles which exhibit an optical interference effect, termed "interference" particles, are most particularly excluded therefrom. Likewise, particles which show a shiny effect, such as metal particles or else particles with a metallic effect, such as bismuth oxychloride, are excluded therefrom.

The term "white" is intended to mean particles having the colour white and its derivatives (off-white, alabaster white, etc.), as opposed to primary colours and derivatives. In particular, the white particles have a lightness value L^* close to 100 in the CIELab76 system.

The scattering white particles according to the invention have an average refractive index of between 1 .7 and 2.2. This is because, if the particle has a refractive index above 2.2, the opacity of the composition is too high, and if this index is below 1 .7, the lightening effect is not sufficient.

The white particles according to the invention have a continuous effect, which is controlled by the resolution capacity of the eye. Since said capacity is around 40 μηη, particles having a volume average size (D50) of less than 40 μηη, preferably less than 25 μηη and even better still less than or equal to 6 μηη are therefore considered. However, it is ensured that particles of which the D50 is greater than 0.3 μηη and preferentially 0.5 μηη are taken, so as not to have too great a loss of opacity, which would be extremely detrimental to the desired effect. Thus, the composition of the invention comprises at least white particles having an average refractive index of between 1.7 and 2.2 and a volume size (D50) of less than 40 μηη, preferably between 0.3 and 25 μηη and better still between 0.3 and 6 μηη, or even between 0.5 and 3 μηι. These particles may be made of one material or else be composites. For example, these particles may be of boron nitride with an average refractive index of 1.74. They may also be chosen from composite particles comprising titanium dioxide and a substrate chosen from alumina, silica, barium sulfate, glass, mica and synthetic mica, poly(methyl methacrylate) (PMMA) particles, polytetrafluoroethylene (PTFE) particles, or mixtures thereof, the average refractive index of which is between 1.7 and 2.2.

According to a first embodiment, the particles are boron nitride particles.

According to another embodiment, the particles are composite particles comprising titanium dioxide and an alumina substrate.

According to another embodiment, the particles are composite particles comprising titanium dioxide and a mica substrate.

The non-interference scattering white particles are advantageously boron nitride particles, preferentially having a volume average size of from 0.3 to 6 μηη. The average refractive index is defined as being the sum of the refractive indices weighted by the weight content in the particle.

As examples of composite particles, mention may, for example, be made of platelets of mica (60%) covered with Ti0₂ (40%), with an average refractive index of 1.9 (0.6x1 .5+0.4x2.5); inclusions of titanium oxide (40%) in a matrix of alumina (60%), with an average refractive index of 1 .96 (0.6x1 .6+0.4x2.5).

The following is a table of the refractive indices used:

Table 1 : Example of the refractive index of various materials

Observation: The refractive index of bismuth oxychloride is here given by way of indication. Of course, said bismuth oxychloride, in its conventional form, does not correspond to a particle for the purposes of the invention, since it is a favoured-reflection particle.

By way of example of particles, mention may be made of boron nitride particles, such as PUHP1030L from Saint Gobain Ceramics and UHP-1010 from Carborundum.

According to one particularly preferred embodiment, use will be made of boron nitride particles having a volume average size D50 of less than 6 μηη, such as the boron nitride particles sold under the name PUHP1030L by Saint Gobain Ceramics, having a volume average size of 3 μηι.

Said non-interference white particles according to the invention are present in the composition in an effective amount for lightening and/or homogenizing the skin and/or the lips, in other words in a content of at least 0.1 % by weight of the total composition, in particular at least 0.5% by weight and preferably at least 1 % by weight.

Said non-interference scattering white particles according to the invention are present in the cosmetic composition in a total amount of active material ranging from 0.1 % to 20% by total weight of the composition and preferably from 0.5% to 10%.

Furthermore, it is possible to add colour, whether it is provided by dyes, or else pigments, lakes, nacres, goniochromatic pigments, etc.

However, when these composite or non-composite particles have a refractive index greater than or equal to, in particular strictly greater than 2.3, care needs to be taken not to exceed 3%. This is because, above this concentration, the lightening effect could be reduced or even extinguished. Furthermore, the latter phenomenon is accompanied by a mask effect.

A cosmetic composition in accordance with the invention advantageously does not contain additional white particle(s) (i.e. particle(s) other than non-interference white particles in accordance with the invention), and in particular does not comprise titanium dioxide.

According to one particular embodiment of the present invention, a composition according to the invention can comprise from 0 to 3% by weight, relative to the total weight of the composition, of particles of Rl > 2.3, in particular of iron oxides.

HYDROPHOBIC AEROGELS:

Silica aerogels are porous materials obtained by replacing (by drying) the liquid component of a silica gel with air.

They are generally synthesized via a sol-gel process in liquid medium and then dried, usually by extraction with a supercritical fluid, the one most commonly used being supercritical C0₂. This type of drying makes it possible to avoid shrinkage of the pores and of the material. The sol-gel process and the various drying operations are described in detail in Brinker C.J. and Scherer G.W., Sol-Gel Science, New York, Academic Press, 1990.

The hydrophobic silica aerogel particles used in the present invention exhibit a specific surface area per unit of mass (S_M) ranging from 500 to 1500 m²/g, preferably from 600 to 1200 m²/g and better still from 600 to 800 m²/g, and a size, expressed as the volume average diameter (D[0.5]), ranging from 1 to 1500 μηη, better still from 1 to 1000 μηη, preferably from 1 to 100 μηη, in particular from 1 to 30 μηη, more preferably from 5 to 25 μηη, better still from 5 to 20 μηη and even better still from 5 to 15 μηη. According to one embodiment, the hydrophobic silica aerogel particles used in the present invention have a size, expressed as volume average diameter (D[0.5]), ranging from 1 to 30 μηη, preferably from 5 to 25 μηη, better still from 5 to 20 μηη and even better still from 5 to 15 μηι.

The specific surface area per unit of mass can be determined by the nitrogen absorption method, known as the BET (Brunauer-Emmett-Teller) method, described in The Journal of the American Chemical Society, Vol. 60, page 309, February 1938 and corresponding to the international standard ISO 5794/1 (appendix D). The BET specific surface area corresponds to the total specific surface area of the particles under consideration.

The sizes of the silica aerogel particles can be measured by static light scattering using a commercial particle size analyser of MasterSizer 2000 type from Malvern. The data are processed on the basis of the Mie scattering theory. This theory, which is exact for isotropic particles, makes it possible to determine, in the case of non-spherical particles, an "effective" particle diameter. This theory is in particular described in the publication by Van de Hulst, H.C., "Light Scattering by Small Particles", Chapters 9 and 10, Wiley, New York, 1957.

According to one advantageous embodiment, the hydrophobic silica aerogel particles used in the present invention have a specific surface area per unit of mass (S_M) ranging from 600 to 800 m²/g and a size, expressed as the volume average diameter (D[0.5]), ranging from 5 to 20 μηη and even better still from 5 to 15 μηη.

The silica aerogel particles used in the present invention may advantageously have a tapped density p ranging from 0.02 g/cm³ to 0.10 g/cm³, preferably from 0.03 g/cm³ to 0.08 g/cm³ and in particular from 0.05 g/cm³ to 0.08 g/cm³.

In the context of the present invention, this density may be assessed according to the following protocol, known as the tapped density protocol:

40 g of powder are poured into a measuring cylinder; the measuring cylinder is then placed on the Stav 2003 machine from Stampf Volumeter; the measuring cylinder is subsequently subjected to a series of 2500 tapping actions (this operation is repeated until the difference in volume between 2 consecutive tests is less than 2%); and then the final volume Vf of tapped powder is measured directly on the measuring cylinder. The tapped density is determined by the ratio m/Vf, in this instance 40/Vf (Vf being expressed in cm³ and m in g).

According to one preferred embodiment, the hydrophobic silica aerogel particles used in the present invention have a specific surface area per unit of volume S_v ranging from 5 to 60 m²/cm³, preferably from 10 to 50 m²/cm³ and better still from 15 to 40 m²/cm³. The specific surface area per unit of volume is given by the relationship: S_v = S_M ^x p where p is the tapped density expressed in g/cm³ and S_M is the specific surface area per unit of mass expressed in m²/g, as defined above.

Preferably, the hydrophobic silica aerogel particles according to the invention have an oil-absorbing capacity, measured at the wet point, ranging from 5 to 18 ml/g, preferably from 6 to 15 ml/g and better still from 8 to 12 ml/g.

The absorption capacity measured at the wet point, denoted Wp, corresponds to the amount of oil which it is necessary to add to 100 g of particles in order to obtain a homogeneous paste.

It is measured according to the "wet point" method or method of determination of oil uptake of a powder described in the standard NF T 30-022. It corresponds to the amount of oil adsorbed onto the available surface of the powder and/or absorbed by the powder by measurement of the wet point, described below:

An amount m = 2 g of powder is placed on a glass plate and the oil (isononyl isononanoate) is then added dropwise. After addition of 4 to 5 drops of oil to the powder, mixing is performed using a spatula, and addition of oil is continued until conglomerates of oil and powder have formed. At this point, the oil is added one drop at a time and the mixture is then triturated with the spatula. The addition of oil is stopped when a firm and smooth paste is obtained. This paste must be able to be spread over the glass plate without cracks or the formation of lumps. The volume Vs (expressed in ml) of oil used is then noted.

The oil uptake corresponds to the ratio Vs/m.

The aerogels used according to the present invention are aerogels of hydrophobic silica, preferably of silylated silica (INCI name: silica silylate).

The term "hydrophobic silica" is intended to mean any silica whose surface is treated with silylating agents, for example halogenated silanes such as alkylchlorosilanes, siloxanes, in particular dimethylsiloxanes such as hexamethyldisiloxane, or silazanes, so as to functionalize the OH groups with silyl groups Si-Rn, for example trimethylsilyl groups.

As regards the preparation of hydrophobic silica aerogel particles modified at the surface by silylation, reference may be made to the document US 7 470 725.

Use will preferably be made of hydrophobic silica aerogel particles that are surface- modified with trimethylsilyl groups.

As hydrophobic silica aerogels that may be used in the invention, an example that may be mentioned is the aerogel sold under the name VM-2260 or VM-2270 (INCI name: Silica silylate) by the company Dow Corning, the particles of which have a mean size of about 1000 microns and a specific surface area per unit of mass ranging from 600 to 800 m²/g.

Mention may also be made of the aerogels sold by the company Cabot under the references Aerogel TLD 201 , Aerogel OGD 201 and Aerogel TLD 203, Enova® Aerogel MT 1 100 and Enova Aerogel MT 1200.

Use will preferably be made of the aerogel sold under the name VM-2270 (I NCI name: Silica silylate), by the company Dow Corning, the particles of which have an average size ranging from 5-15 microns and a specific surface area per unit of mass ranging from 600 to 800 m²/g.

In particular, the hydrophobic silica aerogel particles represent from 0.1 % to 20% by weight, preferably from 0.5% to 10% by weight, better still from 1 % to 10% by weight and more preferably from 1 .5% to 5% by weight relative to the total weight of the composition.

The compositions used according to the invention may in particular constitute cosmetic compositions. They contain, for such an application, a physiologically acceptable medium. The term "physiologically acceptable medium" is intended to mean here a medium which is compatible with the skin, and optionally the lips, the scalp, the eyelashes, the eyes and/or the hair. This physiologically acceptable medium may be more particularly constituted of a physiologically acceptable organic solvent and optionally water. The organic solvent may be chosen, for example, from lower alcohols containing from 1 to 4 carbon atoms, for instance ethanol, isopropanol, propanol or butanol; polyethylene glycols containing from 6 to 80 ethylene oxide units; and polyols, for instance propylene glycol, isoprene glycol, butylene glycol, glycerol and sorbitol. The physiologically acceptable medium of the composition according to the invention has a pH which is compatible with the skin, and preferably ranging from 3 to 8 and better still from 5 to 7.

In one advantageous aspect of the invention, the compositions are in the form of an oil-in- water or water-in-oil emulsion, of a triple emulsion, or else of a gel. Makeup galenical forms (loose powders, compacted powders, sticks, etc.) are also envisaged.

According to one particular embodiment, the emulsion is an oil-in-water emulsion.

The compositions according to the present invention comprise at least one oily phase comprising at least one oil. This oily phase may be present in an amount ranging, for example, from 10% to 95% by weight, preferably from 10% to 80% by weight, better still from 15% to 70% by weight and even better still from 20% to 60% by weight relative to the total weight of the composition.

This oily phase contains at least one oil, in particular one cosmetic oil, and it may contain several oils and optionally one or more other fatty substances.

As oils that may be used in the invention, mention may be made of mineral oils (liquid petroleum jelly), vegetable oils, animal oils (perhydrosqualene), synthetic oils, non-volatile or volatile silicone oils (cyclomethicones such as cyclopentasiloxane and cyclohexasiloxane) and fluoro oils (perfluoropolyethers). As fatty substances, use may also be made of fatty alcohols, fatty acids and waxes. The oily phase of the emulsion may also contain gums, such as silicone gums, resins and waxes.

In a known manner, the compositions of the invention may also contain adjuvants that are common in the cosmetics or dermatological fields, such as hydrophilic or lipophilic gelling agents, hydrophilic or lipophilic active agents, preservatives, antioxidants, solvents, fragrances, fillers, screening agents, bactericides, odour absorbers, colorants and salts. According to one particular embodiment, the composition according to the invention may comprise, as cosmetic adjuvants, nacres, pigments, dyes, biological active agents (anti- ageing, oily skin, whitening, antiperspirant, antioxidant, etc.), sunscreens, film-forming polymers, scattering and/or lightening fillers, oils and fatty substances, moisturizers and emollients.

The amounts 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 and preferably from 0.01 % to 10% of the total weight of the composition. Depending on their nature, these adjuvants may be introduced into the fatty phase, into the aqueous phase and/or into lipid spherules.

As active agents, the composition may contain active agents conventionally used in the cosmetics industry, and for example chosen from desquamating agents, moisturizing agents, depigmenting agents, pro-pigmenting agents, anti-glycation agents, NO-synthase inhibitors, 5oc-reductase inhibitors, lysyl and/or prolyl hydroxylase inhibitors, agents for stimulating the synthesis of dermal or epidermal macromolecules and/or preventing their degradation, agents for stimulating fibroblast or keratinocyte proliferation and/or keratinocyte

differentiation, muscle relaxants, antimicrobial agents, tensioning agents, antipollution agents or free-radical scavengers, anti-inflammatories, agents which act on the microcirculation, and agents which act on the energy metabolism of cells, lipolytic active agents or active agents which have a direct or indirect favourable activity on reducing adipose tissue, and skin whitening agents which do not belong to the optical brightener family. The whitening agents capable of being incorporated into the composition according to the present invention comprise, for example, the following compounds: kojic acid; ellagic acid; arbutin and derivatives thereof, such as those described in applications EP-895 779 and EP- 524 109; hydroquinone; aminophenol derivatives, such as those described in applications WO 99/10318 and WO 99/32077, and in particular N-cholesteryloxycarbonyl-para- aminophenol and N-ethyloxycarbonyl-para-aminophenol; iminophenol derivatives, in particular those described in application WO 99/22707; L-2-oxothiazolidine-4-carboxylic acid or procysteine, and also salts and esters thereof; calcium D-pantetheine sulfonate, ascorbic acid and derivatives thereof, in particular ascorbyl glucoside, and extracts of plants, in particular of liquorice, of blackberry, of skullcap and of Bacopa monnieri, without this list being limiting.

According to one embodiment of the invention, the compositions used may also comprise at least one organic photoprotective agent and/or at least one inorganic photoprotective agent that is active in the UVA and/or UVB range (absorbers), which may be water-soluble or liposoluble, or else insoluble in the commonly used cosmetic solvents. These photoprotective agents are different from optical brighteners.

The photoprotective agents are generally present in the compositions according to the invention in proportions ranging from 0.1 % to 20% by weight, relative to the total weight of the composition, and preferably ranging from 0.2% to 15% by weight relative to the total weight of the composition.

The compositions used according to the invention may be more or less fluid and may have the appearance of a white or coloured cream, an ointment, a balm, a milk, a serum, a paste or a foam. They can optionally be applied to the skin in the form of an aerosol. They can also be in solid form, for example in the form of a stick, suitable in particular for application to the lips.

Thus, the present invention also relates to a cosmetic method for lightening and/or homogenizing the skin and/or the lips, in particular facial skin and/or the shadows around the eyes, comprising the topical application to the skin of a composition according to the invention as defined previously. This cosmetic method will be more particularly intended for immediate lightening and/or homogenizing of the skin and/or of the lips, in particular of the skin.

The composition of the invention may be used as it is or as a care and/or makeup base, applied to the skin before a care product or a makeup product.

The invention also relates to a method for making up and/or for non-therapeutic care of the skin and/or the lips, comprising at least one step of applying to the skin a cosmetic composition according to the invention as defined previously.

Another aspect of the invention relates to the combined use of hydrophobic silica aerogel particles as defined previously and of non-interference scattering white particles as defined previously, as an agent for lightening and/or homogenizing the skin and/or the lips, in particular the complexion, and/or for softening skin defects.

The examples that follow serve to illustrate the invention without, however, being limiting in nature. The compounds are, as the case may be, mentioned as chemical names or as CTFA (International Cosmetic Ingredient Dictionary and Handbook) names.

The amounts are expressed as percentage by weight, relative to the total weight of the composition. Unless otherwise mentioned, the amounts are not indicated as amount of active material, but as crude amount introduced into the composition.

EXAMPLES

Example 1 : Demonstration of the lightening, homogenizing and dvschromia-correcting effects of formulae containing the combination of hydrophobic silica aerogel particles and boron nitride particles

MEASUREMENT PROTOCOL

→ Measurement of the homogenizing power (H)

The formula-spreading protocol consists in producing 50 μηη spreads on a standard contrast chart. The measurements are carried out on white background. Colour measurements are carried out using a colorimeter. This is a Konica Minolta CR-400 chroma meter. The colorimeter provides numerical data representing the absolute value and the difference in colour between a reference sample and a sample to be controlled. The values obtained on the bare chart without film are used as reference.

The operating conditions are as follows:

❖ Standard CI E 1964 10° observer

❖ CIE illuminant D65

❖ Measurement geometry d/0, variant of d/8 The instrument has an optical device which produces a diffuse light, placed in a spherical cavity coated with a white layer which generates multiple light reflection. An anti-glare trap eliminates the effects of glare of the surface of the sample. Initially, a "white plate" calibration of the instrument is carried out.

Then, an average ΔΕ₀ is calculated from the measurements L^*, a^* b^* of the bare ethnic chart. This is the difference in colour between a zone of small surface area and the corresponding large zone. For example, on the African-American chart (contrast chart 32 described below), the average of the colour differences between B1 1 and B1 1 +, B12 and B1 1 +, and so on, is calculated:

_{A c} ∑[AEo - n]

averageA E₀ =—

n

n = 1 , 2, ... , n

A transparency bearing a spread (referred to as a film) is then placed over the ethnic chart. The same measurements are carried out and the average ΔΕ is obtained. Finally, H, which corresponds to the homogenizing power of the formula spread on the transparency, is determined according to the equation:

H = average ΔΕ₀ / average ΔΕ In particular, these measurements are carried out on a contrast chart 32 as defined in application EP 1 433 461 and represented in Figure 4 of said application.

The contrast chart 32 comprises a square coloured zone B1 1 + and four rectangular coloured zones B1 1 , B12, B12+ and XXX.

The various zones B1 1 , B1 1 +, B12, B12+ and XXX are preferably made by printing of inks chosen such that these zones appear to an observer to be of the same colour under at least two different illuminants, as described in European patent application EP 1 212 961.

The contrast chart 32 may be representative of skin of which the lightness is between 30 and 40.

Thus, the various zones B1 1 +, B1 1 , B12, B12+ and XXX may correspond to the average colours observed on a panel of individuals who have dark skin with a dark complexion, for various regions of the face. The region B1 1 + may correspond to the average of the colour measured on the forehead in the zones V1 , averaged with that measured on the cheekbones in the zones V2.

The zone B1 1 may correspond to the colour measured on the cheekbones, in the zone V2, the zone B12 to that measured on the forehead, in the zones V1 , the zone B12+ to the average colour between that measured on the outer shadows in the zones V3, that measured in the middle shadows of the zones V4 and that measured around the lips in the zones V5. The zone XXX may correspond to the colour of the inner shadows, measured in the zones V6.

The contrast chart 32 is characterized, for each zone, by the following values:

Where L^* is the lightness, and C^* the saturation, and h the shade, in the CIE 1976 colorimetric space.

→ Measurement of the lightening power (E)

E, which corresponds to the lightening power of the formula spread on the transparency, is determined. This is the measurement of the ΔΕ between the zone B1 1 + of the chart before and after treatment.

E = ΔΕ B11 + before after → Measurement of the Coverage (CR)

The same spreads as for the determination of the homogenizing power are used . Three spectral reflectance measurements are carried out on each of the two backgrounds of the contrast chart by applying the measuring head, of the spectrocolorimeter, directly on the 50

im films. The values obtained are: X, Y and Z.

The contrast ratio is calculated by producing the mathematical average of the three values of the Ys on black background, divided by the average of the three Ys on white background, multiplied by 100.

Average (Yblack )

Contrast Ratio = * 100

Average (y white )

→ Measurement of Haze and of Transparency

The measurements were carried out using the Haze-gard from the company Byk Gardner.

This instrument characterizes the visual perception by means of objective measurement values:

· Transmittance TH

• Haze (haze→ soft focus property)

Compositions films of 25 μηι are applied on polyethylene (PE) films of 50 μιη.

The film is then measured after one hour of drying at ambient temperature. The film is then placed in the instrument and transparency and haze measurements are carried out.

FORMULATION

The support studied is a direct emulsion. Various combinations were introduced into this base (Example 1 ) and measurements for optical characterization of the formulae were then carried out. The results are given in the following tables:

Ingredients Control comparative comparative invention invention invention base (ex. 2) (ex. 3) (ex. 4) (ex. 5) (ex. 6) (ex. 1 )

Silica silylate 1 1 1 1 (VM-2270 Aerogel Fine

Particles from Dow

Corning) Glyceryl acrylate/ 0.175 0.175 0.175 0.175 0.175 0.175 acrylic acid copolymer

Boron nitride 2.5 2.5 2.5 7.5 (PUHP 1030L from

Saint Gobain Ceramics)

Triethanolamine 0.245 0.245 0.245 0.245 0.245 0.245

Xanthan gum 0.1 0.1 0.1 0.1 0.1 0.1

Caprylyl glycol 0.5 0.5 0.5 0.5 0.5 0.5

Myristyl alcohol 0.05 0.05 0.05 0.05 0.05 0.05

Stearyl alcohol 0.05 0.05 0.05 0.05 0.05 0.05

Mica/titanium dioxide/tin 0.5

oxide

(Timiron Silk Blue from

Merck)

Disodium EDTA 0.099 0.099 0.099 0.099 0.099 0.099

Glyceryl stearate 1.05 1 .05 1 .05 1 .05 1.05 1 .05

Cetyl alcohol 1 .9 1.9 1.9 1 .9 1 .9 1.9

Pentylene glycol 1 1 1 1 1 1

Myristic acid 0.024 0.024 0.024 0.024 0.024 0.024

Glycerol 1 1.2 1 1.2 1 1.2 1 1.2 1 1.2 1 1.2

Palmitic acid 0.352 0.352 0.352 0.352 0.352 0.352

Stearic acid 0.424 0.424 0.424 0.424 0.424 0.424

Isostearyl 6 6 6 6 6 6 neopentanoate

Dimethicone 5 5 5 5 5 5 (Xiameter PMX-200

Silicone Fluid 10CS)

Pentaerythrityl 4 4 4 4 4 4 tetrakis(ethylhexanoate)

(Nikkol Pentarate 408

from Nikko)

Water q.s. for q.s. for 100 q.s. for 100 q.s. for q.s. for q.s. for

100 100 100 100

Mineral oil 2.55 2.55 2.55 2.55 2.55 2.55

Carbomer (Carbopol 0.2 0.2 0.2 0.2 0.2 0.2 981 Polymer from Lubrizol)

PEG-100 Stearate 1.05 1 .05 1 .05 1 .05 1.05 1 .05

Polysorbate 60 0.9 0.9 0.9 0.9 0.9 0.9

Results

The results are given in the following table:

It is noted that the combination of the silica aerogel with boron nitride particles makes it possible to obtain high transparency (TH), haze, lightening (E) and homogenizing power (H) levels while at the same time maintaining the coverage (CR) at values below 50.

Example 2: Formulations

Oil-in-water emulsion

Chemical name % by weight

Ethylenediaminetetraacetic acid, disodium salt. 2 H₂0 0.1

Triethanolamine 0.245

Trimethylated silica (free flowing powder) 1

Liquid petroleum jelly 2.55

Isostearyl neopentanoate 6

Pentaerythrityl tetraoctanoate 4

Pure double-distilled cetyl alcohol 2

Xanthan gum 0.1

Carboxyvinyl polymer synthesized in the ethyl 0.2

acetate/cyclohexane mixture

Acrylic polymer in water/glycerol at 1 %, unstabilized 10

(Lubrajel PF from United Guardian)

Polydimethylsiloxane (viscosity: 10 cSt) 5

Microbiologically clean deionized water q.s. foM OO Glycerol 4.5

1 ,2-Pentanediol 1

1 ,2-Octanediol 0.5

Oxyethylenated (20 EO) sorbitan monostearate 0.9

Fatty acids (predominantly stearic acid) of vegetable origin 0.8

Glyceryl mono/distearate / polyethylene glycol stearate 2.1

mixture (100 EO)

PROCEDURE

1/ Heat the fatty substances of the formula at 75°C until complete homogenization. 21 In parallel, heat the aqueous phase until complete solubilization.

3/ Emulsify by pouring the fatty phase into the aqueous phase at 65°C.

4/ Cool to 50°C and add the oily phase until a smooth appearance is obtained.

5/ At around 40-45°C, introduce the acrylic polymer.

6/ Introduce the silica aerogel until a smooth appearance is obtained.

II Finally, add the triethanolamine until a smooth appearance is obtained.

When applied to facial skin, this composition gives a lightening effect with transparency.

Oil-in-water emulsion

The following example was carried out:

US INCI % by weight

PEG-12 dimethicone 0.7

Silica silylate (VM-2270 Aerogel Fine Particles 0.98

from Dow Corning)

Glyceryl acrylate/acrylic acid copolymer 0.0525

Boron nitride (PUHP 1030L from Saint Gobain 1

Ceramics)

Caprylyl glycol 0.4

Synthetic fluorphlogopite 0.6

Titanium dioxide 0.37

Glycerol 9

Propylene glycol 2

Dimethicone 10 cSt 7

Dimethicone 5 cSt 4

Denatured alcohol 8

Water q.s. for 100

Ammonium polyacryloyldimethyl taurate 1

(Hostacerin AMPS from Clariant) When tested on the skin of 12 models in India, this composition gives a lightening effect with transparency.

It is understood that, in the context of the present invention, the weight percentages given for a compound or a family of compounds are always expressed as weight of solids of the compound in question.

Throughout the application, the expression "comprises one" or "includes one" should be understood as meaning "comprises at least one" or "includes at least one", unless otherwise specified.

Claims

1. Cosmetic composition comprising, in a physiologically acceptable medium, at least one oil, at least hydrophobic silica aerogel particles and at least 0.1 % by weight of non-interference scattering white particles characterized by 0.3 μη"ΐ<Ο50<40 μηη and 1.7<RI<2.2.

2. Cosmetic composition according to Claim 1 , characterized in that the hydrophobic silica aerogel particles exhibit a specific surface area per unit of mass (S_M) ranging from 500 to 1500 m²/g, preferably from 600 to 1200 m²/g and better still from 600 to 800 m²/g, and a size, expressed as the volume average diameter (D[0.5]), ranging from 1 to 1500 μηη, preferably from 1 to 1000 μηη, even more preferentially from 1 to 100 μηη, in particular from 1 to 30 μηη, more preferably from 5 to 25 μηη, better still from 5 to 20 μηη and even better still from 5 to 15 μηη.

3. Composition according to any one of the preceding claims, characterized in that the hydrophobic silica aerogel particles have an oil-absorbing capacity, measured at the wet point, ranging from 5 to 18 ml/g of particles, preferably from 6 to 15 ml/g and better still from 8 to 12 ml/g.

4. Composition according to any one of the preceding claims, characterized in that the hydrophobic silica aerogel particles have a tapped density ranging from 0.02 g/cm³ to 0.10 g/cm³, preferably from 0.03 g/cm³ to 0.08 g/cm³ and in particular from 0.05 g/cm³ to 0.08 g/cm³.

5. Composition according to any one of the preceding claims, characterized in that the hydrophobic silica aerogel particles are hydrophobic silica aerogel particles that are surface- modified with trimethylsilyl groups, preferably having the I NCI name Silica silylate.

6. Composition according to one of the preceding claims, characterized in that the hydrophobic aerogel particles represent from 0.1 % to 20% by weight, preferably from 0.5% to 10% by weight, better still from 1 % to 10% by weight and more preferably from 1 .5% to 5% by weight, relative to the total weight of the composition.

7. Composition according to any one of Claims 1 to 6, characterized in that the noninterference scattering white particles are chosen from boron nitride, composite particles comprising titanium dioxide and a substrate chosen from alumina, silica, barium sulfate, glass, mica and synthetic mica, poly(methyl methacrylate) (PMMA) particles, polytetrafluoroethylene (PTFE) particles, or mixtures thereof, the average refractive index of which is between 1 .7 and 2.2.

8. Composition according to the preceding claim, characterized in that the non-interference scattering white particles are of boron nitride.

9. Composition according to any one of the preceding claims, characterized in that said noninterference scattering white particles according to the invention are present in the cosmetic composition in a total amount of active material ranging from 0.1 % to 20% by total weight of the composition and preferably from 0.5% to 10%.

10. Composition according to any one of the preceding claims, characterized in that it is a care and/or makeup base, applied alone or under a care and/or makeup product.

11. Composition according to any one of Claims 1 to 10, characterized in that it is in the form of an oil-in-water emulsion.

12. Composition according to any one of the claims, characterized in that it comprises from 0 to 3% by weight, relative to the total weight of the composition, of particles of Rl > 2.3, in particular of iron oxides.

13. Composition according to any one of the preceding claims, characterized in that it also contains at least one cosmetic ingredient chosen from desquamating agents, moisturizing agents, depigmenting agents, anti-glycation agents, agents for stimulating fibroblast or keratinocyte proliferation and/or keratinocyte differentiation, tensioning agents, antipollution agents or free-radical scavengers, agents which act on the microcirculation, and agents which act on the energy metabolism of cells, organic photoprotective agents and inorganic photoprotective agents that are active in the UVA and/or UVB range, and skin whitening agents.

14. Cosmetic method for lightening and/or homogenizing the skin and/or the lips, in particular the skin, comprising the topical application to the skin of a composition as defined in one of Claims 1 to 13.

15. Cosmetic method according to Claim 14, characterized in that it is intended for immediate lightening and/or homogenizing of the skin and/or of the lips, in particular of the skin.

16. Use of the combination of at least hydrophobic silica aerogel particles and of at least 0.1 % by weight of non-interference scattering white particles characterized by 0.3 μη"ΐ<Ο50<40 μηη and 1.7<RI<2.2 in a cosmetic composition for softening skin defects.