Novel cosmetic uses of porous metal oxide spheres.

Abstract

The present invention relates to the cosmetic use of porous spheres comprising a metal oxide for improving the appearance and / or comfort of the skin, skin appendages, in particular hair, and / or mucous membranes. The present invention further relates to cosmetic or pharmaceutical compositions comprising said spheres.

Description

[Technical Field]

[0001] The present invention relates to the cosmetic use of porous metal oxide spheres for improving the aesthetic appearance and comfort of the skin, skin integuments, in particular hair, and / or mucous membranes, and also to said cosmetic compositions and cosmetic treatment methods obtained therefrom.The present invention also relates to pharmaceutical compositions, in particular dermatological compositions, comprising porous metal oxide spheres for improving the comfort of skin, skin integuments and / or mucous membranes that are subject to pathological conditions. [Background technology]

[0002] Visibly improving the appearance of skin and hair is one of the main challenges in cosmetics. Cosmetic consumers are always seeking cosmetic solutions to effectively mask signs of skin and / or hair that are considered unaesthetic. These signs naturally appear with aging, but can also result from chronic exposure to various factors. These can be environmental factors such as pollution, wind, climate change, especially excessive temperature fluctuations due to air conditioning, and dryness. These can be mechanical aggressive factors such as shaving, friction, and hair removal, and / or chemical aggressive factors such as hair treatments, especially bleaching, dyeing, waving and straightening, cleansing agents, and exfoliation treatments. These factors cause damage to the skin, skin integument, and / or mucous membranes, which is often reflected in visible symptoms that are considered unaesthetic. Intrinsic factors, especially stress, hormonal fluctuations, weight gain, dieting, and dryness, contribute to their appearance. Genetic characteristics, especially skin type (sensitive, hyperseborrheic, reactive, etc.) and ethnic origin (for example Caucasian, Asian or African), also play an important role in the appearance of certain conditions.

[0003] Unaesthetic skin manifestations are, in particular, wrinkles and fine lines, such as lion wrinkles and crow's feet. These wrinkles are initially superficial and then become deeper (e.g., nasolabial folds). The above-mentioned skin manifestations also include signs of loss of skin volume, particularly skin breakdown and loosening of facial contours, which leads to breakdown of facial lines, giving a sad or tired appearance, or loss of density, reflected in thinner, more fragile skin with loss of radiance and / or dull complexion. Thus, unaesthetic skin manifestations also include loss of complexion uniformity, loss of radiance, dark circles or sagging under the eyes, rashes, melasma or age spots, or pigmentary conditions such as white spots, especially vitiligo, rosacea, melasma of pregnancy, melasma, birthmarks, and hemangiomas. These also include skin imperfections such as blackheads, prominent pores, pimples, scars, especially acne scars, burns, wounds, and stretch marks, as well as rough skin and scaling. On mucous membranes, unaesthetic manifestations are generally dry marks such as scales and / or cracks. On hair, unaesthetic manifestations are generally dull, brittle hair that is difficult to style, particularly unmanageable, with split ends.

[0004] These conditions, especially those that appear on the face and around the eyes, are perceived as unaesthetic by consumers. Some of these can be corrected by cosmetic surgery, but this is not always the case, and the results can be unsatisfactory because the results of the treatment are perceived as incomplete, unnatural, irritating, or even painful, and are often expensive. Many consumers do not have the means or are unwilling to cover the costs of such treatments. Many cosmetic options exist to mask or reduce these undesirable conditions. Makeup, especially foundation, aims to provide a solution for hiding wrinkles and evening out the complexion. However, consumers also seek a natural, healthy complexion effect that does not transfer pigments to clothing, and also a happy effect during application.

[0005] Patent application WO 2016 / 198537 describes porous particles of inorganic material containing spherical pores and coated with a hydrophobic coating, which are intended to lighten or correct the color of human keratinous substances and to quickly even out the complexion.

[0006] However, as shown on page 10, line 16 of the above document, these particles are not spherical but have a polydisperse shape. Moreover, they are irregularly shaped. Furthermore, the presence of a hydrophobic coating is essential. Here, the size of the particles affects light scattering and therefore the effect of the particles on the skin. Therefore, the fact that the particles in the above document do not have a uniform, particularly monodisperse, size is a drawback, because it is not possible to accurately select the optical effect that the particles will have on the skin, and it undoubtedly explains the necessity of the presence of a hydrophobic coating, which may have consequences on the skin such as allergies and intolerances. Therefore, there is a need to find a better alternative to these particles. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] WO 2016 / 198537 Summary of the Invention

[0008] The present invention is therefore directed to meeting the ongoing need for cosmetic options to improve the appearance of the skin, skin integument, and / or mucous membranes, particularly by masking unaesthetic conditions. The present invention is also directed to providing novel cosmetic ingredients that are easy to formulate and have no side effects, and in particular do not cause skin irritation.

[0009] Applicant has discovered that metal oxide spheres have properties that improve the appearance and / or comfort of the skin and / or mucous membranes and / or skin integuments, particularly hair.

[0010] In particular, such spheres have a unique ability to reflect and scatter light, making it possible to smooth the surface of the skin, skin integument and / or mucous membranes, thus concealing their unaesthetic appearance and enhancing their radiance, and they also impart a soft, silky feel to compositions containing them.

[0011] The spheres according to the invention offer the advantage of being suitable for any skin, regardless of its type, complexion or radiance. Another advantage of the invention is that the spheres have excellent stability and can be used in powder or composition form. Because the spheres are inert, they can be easily formulated into cosmetic or dermatological compositions of any nature, regardless of whether such compositions are lipophilic or hydrophilic.

[0012] Another advantage is that the spheres can be used together with conventional ingredients of cosmetic compositions, in particular pigments or colorants, to contribute to masking non-aesthetic conditions, in particular imperfections. DETAILED DESCRIPTION OF THE INVENTION

[0013] According to an advantageous embodiment, the spheres according to the invention can be used in foundation and / or make-up products.

[0014] One subject of the present invention is therefore the cosmetic use of porous spheres comprising metal oxides to improve the appearance and / or comfort of the skin, the skin integument, in particular the hair, and / or the mucous membranes.

[0015] According to a preferred embodiment, the porous spheres have an average diameter of 0.5 μm to 100 μm, advantageously 1 μm to 100 μm, in particular 4.5 μm to 9.9 μm, and / or an average porosity of 0.10 to 0.90, preferentially 0.10 to 0.80, and / or an average pore size of 50 nm to 999 nm, advantageously 50 nm to 500 nm, in particular 100 nm to 400 nm, more particularly 220 nm to 300 nm.

[0016] Advantageously, the porous spheres have an average diameter of 0.5 μm to 100 μm, advantageously 1 μm to 100 μm, in particular 4.5 μm to 9.9 μm, and an average porosity of 0.10 to 0.90, preferentially 0.10 to 0.80, and an average pore size of 50 nm to 999 nm, advantageously 50 nm to 500 nm, in particular 100 nm to 400 nm, more particularly 220 nm to 300 nm.

[0017] Preferentially, the metal oxide of the spheres is selected from the oxides silica, titania, alumina or zirconia, cerium oxide, iron oxide, zinc oxide, indium oxide, tin oxide, chromium oxide, mixed metal oxides and combinations thereof, preferentially silica, titania, alumina and zinc oxide and combinations thereof, more preferentially silica and titanium oxide and combinations thereof.

[0018] Preferentially, the porous spheres comprise between 60% and 99.9% by weight of metal oxide and between 0.1% and 40% by weight of light absorber relative to the total weight of the spheres.

[0019] Preferentially, the spheres have an average diameter between 1 μm and 75 μm and an average porosity between 0.45 and 0.65.

[0020] According to a particular embodiment of the invention, the spheres have an average diameter of 4.5 μm to 9.9 μm, an average porosity of 0.45 to 0.65 and an average pore size of 220 nm to 300 nm.

[0021] A subject of the invention is also a cosmetic composition comprising these porous spheres, in particular for the uses mentioned above.

[0022] A subject of the present invention is also pharmaceutical compositions, preferentially dermatological compositions, useful for improving the comfort of the skin, integuments and / or mucous membranes, in particular those suffering from pathological conditions.

[0023] Such a cosmetic or pharmaceutical composition, preferentially a dermatological composition, may contain 1 x 10 spheres relative to the total weight of the composition. -3 It is present in a concentration of up to 100% by weight, preferentially between 0.5% and 5% by weight.

[0024] The use according to the invention is preferentially a cosmetic use, preferentially in humans, and by topical application to at least one area or part of concern of healthy skin, healthy mucous membranes and / or healthy skin integument, preferentially hair.

[0025] For the purposes of the present invention, the term "cosmetic use" means the non-therapeutic, non-medicinal use of the spheres according to the invention, preferentially on healthy skin, in particular on healthy scalp, and / or on healthy skin integuments, in particular on healthy hair, and / or on healthy mucous membranes.

[0026] For the purposes of the present invention, the expression "a portion of the skin, preferentially a portion of the scalp and / or an area of ​​the skin, preferentially an area of ​​the scalp, that is called "healthy"" means a portion of the skin, preferentially a portion of the scalp and / or an area of ​​the skin, preferentially an area of ​​the scalp, that is said by a dermatologist to be non-diseased, i.e. a portion of the skin, preferentially a portion of the scalp and / or an area of ​​the skin, preferentially an area of ​​the scalp, that does not show any skin infection, inflammation, disease or ailment, such as folliculitis, candidiasis, psoriasis, ichthyosis, pathological conditions, wounds or trauma.

[0027] The term "topical application" as used herein means applying the spheres according to the invention, optionally in the form of an active ingredient and / or in the form of a composition, to the surface of the skin, such as the scalp, the skin integument, in particular the hair, and / or mucous membranes, in particular by direct application or by spraying.

[0028] The term "improving appearance" means reducing or diminishing the visibility of unaesthetic conditions present preferentially on the face, in particular by filling and / or by optical effects, in particular by masking or concealing them.

[0029] According to the present invention, "non-aesthetic symptoms" are non-aesthetic irregularities in the relief and / or texture of the skin, mucous membranes and / or skin integument and / or irregularities in the color of the skin, mucous membranes and / or skin integument.

[0030] According to the invention, non-aesthetic irregularities in the relief and texture of the skin are wrinkles and fine lines, in particular lion's wrinkles and crow's feet, raised points, blackheads, enlarged pores, rough appearance, marks and scars, in particular marks and scars caused by trauma, acne, pimples, burns, and / or stretch marks.

[0031] According to the invention, skin colour irregularities are pigmentation marks, in particular white or dark spots, in particular age spots or hyperpigmented or depigmented marks, melasma of pregnancy, moles, melanomas, freckles and rashes, and also loss of complexion radiance, dull complexion, dark circles and bags under the eyes, rosacea and couperosis.

[0032] According to a preferred embodiment, the non-aesthetic symptoms are selected from wrinkles, fine lines, blackheads, prominent pores, loss of complexion radiance, dull complexion, dark circles and bags under the eyes, pigmentation marks and any mixture thereof.

[0033] The unaesthetic symptoms of the skin integument, and preferentially of the hair, are a dull and brittle appearance. For body and scalp hair, these symptoms also include a brittle, fragile, damaged appearance and / or difficulty in shaping and styling the hair, and / or split ends.

[0034] Non-aesthetic symptoms of the mucous membranes are in particular a dull, cracked, shriveled and / or damaged appearance, and also scaling.

[0035] In general, non-cosmetic improvement can be visualized and assessed by microscopy and / or by analysis of high-resolution photographs, particularly by measuring the gloss of areas of the skin, mucous membranes and / or skin integument.

[0036] The improvement in complexion radiance or glow can be measured using, inter alia, objective instrumental methods. This in vivo measurement method consists in taking high-resolution photographs in a cross-polarized configuration of the face of a volunteer taken at 45 degrees before and after application of the test product. Based on these digital photographs, image analysis can be used to measure specific parameters related to skin color, radiance, uniformity, and texture, such as: * , a * , b * , C, h°) and allows for their extraction and quantification.

[0037] Similarly, gloss can be measured according to this method, in particular based on high-resolution photographs of the faces of volunteers taken at 45° in crossed and parallel polarized light configurations before and after the application of the test product. Based on these digital photographs, image analysis allows the extraction and quantification of specific parameters related to gloss, such as specular gloss and contrast gloss.

[0038] For the purposes of the present invention, the term "reducing the visibility of skin pores" means masking skin pores, in particular by filling and / or by optical effects.

[0039] The visibility of skin pores can be demonstrated in vivo by objective instrumental methods (image analysis) that allow the extraction and quantification of specific parameters from high-resolution photographs in cross-polarized configuration of the face of volunteers taken before and after application of a composition containing spheres according to the invention. The density of skin pores can also be measured in vivo by imaging, in particular by fringe projection techniques, measuring a parameter known as curvature.

[0040] In one preferred embodiment of the invention, the spheres according to the invention are in an amount effective to reduce the visibility of skin pores by at least 10%, preferentially by at least 20%, after application of a cream containing the spheres according to the invention, more preferentially prepared under the conditions described in one of Examples 1 to 3 and preferentially formulated in the form of a cosmetic composition as described in Example 6.

[0041] The term "mucous membrane" means the mucous membranes of the eyes, the mucous membranes of the vagina, the mucous membranes of the urogenital tract, the mucous membranes of the anus, the mucous membranes of the nose and / or the mucous membranes of the cheeks, lips and / or gums, preferentially the mucous membranes of the eyes and / or the mucous membranes of the cheeks.

[0042] In the context of the present invention, the term "improving comfort" means enhancing the sensory properties of the composition, in particular the feel and ease of application, in particular by providing a soft, silky, light and smooth feel, and also providing a feeling of softness to the area where the composition containing the spheres is applied. The sensory properties and in particular the feel of the composition can be evaluated according to conventional methods in the art, in particular by evaluation by people trained to carry out sensory tests on the skin. For a better evaluation, measurements are carried out in comparison with a placebo (i.e. the same composition without the spheres according to the invention). This evaluation is preferentially carried out on emulsions.

[0043] Advantageously, the improvement in comfort is analyzed by sensory evaluation of the cream as described in Example 6. A panel of trained individuals evaluates the composition by applying a given amount of the composition to their forearm. According to a prescribed procedure, the composition is spread on the skin and its specific characteristics, such as its absorption, softness, and appearance, are evaluated in comparison with a placebo composition. A value between -1 and +1 is given. For example, for the sensation of lightness, the test composition can be rated +1 to indicate that it is significantly lighter than the "placebo" reference composition, or a value of -0.5 indicates that it is slightly less light than the placebo composition.

[0044] If the two creams give the same sensation, the trained personnel will give a value of 0 for the evaluated parameter. Such evaluation is carried out in the same manner for the test and reference compositions, under the same climatic and blind conditions. Statistical analysis then makes it possible to assess the significance and deviation of the evaluation results.

[0045] The term "skin integument" means hair, eyelashes, eyebrows, beard, moustache and / or nails, preferentially hair.

[0046] Advantageously, the use according to the invention makes it possible to improve the appearance of the skin, in particular by concealing unaesthetic texture, relief and / or color manifestations of the skin, improving the radiance of the complexion, making it more even and shining, and imparting a fresh, bright and healthy complexion effect.

[0047] According to another embodiment, the spheres also make it possible to soften skin showing signs of discomfort, in particular skin that has been exposed to aggressive conditions of a mechanical nature, such as shaving, massage and hair removal, and / or aggressive conditions of a chemical nature, such as hair treatments, in particular bleaching, dyeing, waving and straightening, cleansing agents and exfoliating care treatments.

[0048] In a particular embodiment, the use according to the invention makes it possible to lighten and eliminate the skin, the skin integument, in particular the hair, and / or the mucous membranes, making them more uniform, creating a soft focus effect, softening lines and in particular as a filler to fill irregular lines and marks, in particular wrinkles.

[0049] The spheres according to the present invention are porous metal oxide spheres. Such spheres are photon beads, which means that they have a certain periodic color variation.

[0050] The spheres according to the invention comprise a metal oxide and preferentially have an average diameter of from about 0.5 μm to about 100 μm, advantageously from 1 μm to 100 μm, in particular from 4.5 μm to 9.9 μm, and / or an average porosity of from about 0.10 to about 0.90 or from about 0.10 to about 0.80, and / or an average pore size of from about 50 nm to about 999 nm, advantageously from 50 nm to 500 nm, in particular from 100 nm to 400 nm, more particularly from 220 nm to 300 nm.

[0051] Porous spheres containing metal oxides can be prepared using sacrificial polymer models, and such porous spheres exhibit colors observable by the human eye.

[0052] According to one embodiment, an aqueous colloidal dispersion containing polymer particles and a metal oxide is prepared, with the polymer particles typically being nanometer-sized. This aqueous colloidal dispersion is then mixed in an oily continuous phase, for example, using a microfluidic device, to produce a water-in-oil emulsion. Aqueous droplets of the emulsion are obtained, which are collected and dried to form spheres containing polymer nanoparticles and metal oxide nanoparticles. The nanoparticles (nanospheres) are then removed, for example, by calcining, to produce micrometer-sized spherical particles of the metal oxide containing highly porous nanoparticles and nanometer-sized pores. The spheres can contain uniform pore sizes due to the use of spherical and monodisperse polymer particles.

[0053] The emulsion droplets containing polymer nanospheres and metal oxide are dried to remove the solvent, thus producing spheres (model microspheres or "direct structures") formed from the polymer nanospheres and metal oxide in the interstitial spaces between the polymer nanospheres.

[0054] The polymer nanospheres described above define interstitial spaces. Calcination removes the polymer, thus resulting in highly porous or interstitial volume metal oxide spheres (inverse structures). The porous metal oxide spheres are advantageously sintered to yield a reinforced, continuous solid structure that is thermally and mechanically stable.

[0055] In certain embodiments, droplet formation and collection is performed in a microfluidic device.

[0056] A microfluidic device is, for example, a device having narrow channels with microscopic junctions suitable for generating uniform droplets connected to a collection reservoir.

[0057] Microfluidic devices include junctions with channel widths of, for example, 10 μm to approximately 100 μm. These devices are made, for example, from polydimethylsiloxane (PDMS) and can be fabricated, for example, by soft lithography. Emulsions can be prepared inside the device by pumping a given ratio of aqueous dispersed phase to oily continuous phase, thus forming an emulsion by mixing the two phases. Alternatively, oil-in-water emulsions can be used.

[0058] According to the present invention, the metal oxides include oxides of transition metals, metalloids and earth metals that are compatible with cosmetic and / or dermatological applications, such as the oxides silica, titania, alumina or zirconia, cerium oxide, iron oxide, zinc oxide, indium oxide, tin oxide, chromium oxide, mixed metal oxides and combinations thereof, preferentially chosen from silica oxide and titanium oxide and / or combinations thereof.

[0059] The weight ratio (wt / wt) of polymer nanoparticles to metal oxide is, for example, from about 0.1 / 1 to about 10.0 / 1 or from about 0.5 / 1 to about 10.0 / 1. Advantageously, this ratio is: 0.1 / 1, 0.5 / 1, 1.0 / 1, 1.5 / 1, 2.0 / 1, 2.5 / 1, 3.0 / 1, 3.5 / 1, 4.0 / 1, 5.0 / 1, 5.5 / 1, 6.0 / 1, 6.5 / 1, 7.0 / 1, 8.0 / 1, 9.0 / 1 or 10.0 / 1.

[0060] The continuous oily phase may comprise, for example, an organic solvent, silicone oil, or fluoro oil. According to the present invention, the term "oil" refers to a water-immiscible organic phase. Organic solvents include, for example, hydrocarbons such as heptane, hexane, toluene, and xylene, as well as alcohols such as methanol, ethanol, and propanol.

[0061] The emulsion droplets are collected and dried to remove the polymer, which is carried out according to conventional techniques, for example by microwave irradiation in a heated oven, under vacuum, in the presence of a dehydrating / absorbent agent, or by a mixture of these techniques.

[0062] The polymer is removed according to conventional techniques, for example by calcination, pyrolysis, or with a solvent. According to one embodiment, calcination is carried out at a temperature of 200°C to about 1200°C. According to one embodiment, the calcination temperature is at least 200°C, preferentially at least 500°C, and more preferentially at least 1000°C. Alternatively, the calcination temperature is 200°C to about 700°C. Calcination is carried out for a suitable time range, for example, from 0.1 hours to about 12 hours, preferentially from 1 hour to 8 hours. In certain embodiments, calcination is carried out for at least 0.1 hours, at least 1 hour, at least 5 hours, or at least 10 hours.

[0063] Alternatively, a liquid dispersion containing polymer nanoparticles and metal oxide nanoparticles can be formed in an oily dispersed phase and a continuous aqueous phase to form an oil-in-water emulsion, in which case the oily droplets can be collected and dried in the same manner as the aqueous droplets.

[0064] The spheres are spherical or substantially spherical and micrometer-sized. They thus have an average diameter of 0.5 microns (μm) to about 100 μm, preferably 1 μm to 100 μm, and particularly 4.5 μm to 9.9 μm. The polymer nanoparticles used as models are also spherical and nanometer-sized; they are monodisperse and have an average diameter of 50 nm to about 999 nm, preferably 50 nm to 500 nm, and particularly 100 nm to 400 nm. The metal oxides used may also be in the form of particles, which may therefore be nanometer-sized.

[0065] The metal oxide in the dispersion may be provided in the form of a metal oxide or in the form of a metal oxide precursor, for example via sol-gel techniques.

[0066] Drying of the polymer / metal oxide droplets and subsequent removal of the polymer allows for the formation of spheres containing uniform cavities (pores). Generally, in the described method, each droplet forms a single microsphere. The pore size depends on the size of the polymer particles. During the removal of the polymer, shrinkage or compaction may occur, resulting in pore sizes slightly smaller than the initial size of the polymer particles, for example, 10% to 40% smaller than the initial polymer particle size. The pore size is uniform, as are the shape and size of the polymer particles.

[0067] The pore size of the spheres according to the invention is between about 50 nm and about 999 nm, advantageously between 50 nm and 500 nm, in particular between 100 nm and 400 nm.

[0068] The average porosity of the spheres can be relatively high, for example, from about 0.10 or about 0.30 to about 0.80 or about 0.90. The average porosity of a microsphere indicates the total pore volume as a percentage of the total volume of the microsphere. Average porosity can also be referred to as "volume fraction." It is a dimensionless magnitude.

[0069] In certain embodiments, the porous spheres have a solid center or core, with the porosity facing the outer surface of the sphere.

[0070] In another embodiment, the porous sphere has a hollow center and the porosity increases towards the inside of the sphere.

[0071] Thus, in certain embodiments, there is a porosity gradient towards the center of the sphere or a porosity gradient towards the outside of the sphere.

[0072] In another preferred embodiment of the invention, the porosity is distributed uniformly throughout the volume of the sphere.

[0073] In the porous spheres according to the invention, the average diameter of the spheres is significantly larger than the average diameter of the pores, for example, the average diameter of the spheres is generally at least 25 times, preferentially at least 30 times, preferentially at least 35 times, more preferentially 4 times larger than the average diameter of the pores.

[0074] In certain embodiments, the ratio of the average diameter of the microspheres to the average diameter of the pores is at least 40 / 1, at least 50 / 1, at least 60 / 1, at least 70 / 1, at least 80 / 1, at least 90 / 1, at least 100 / 1, at least 110 / 1, at least 120 / 1, at least 130 / 1, at least 140 / 1, at least 150 / 1, at least 160 / 1, at least 170 / 1, at least 180 / 1, at least 190 / 1, at least 200 / 1, at least 210 / 1, at least 220 / 1, at least 230 / 1, at least 240 / 1, at least 250 / 1, at least 260 / 1, at least 270 / 1, at least 280 / 1, at least 290 / 1, at least 300 / 1, at least 310 / 1, at least 320 / 1, at least 330 / 1, at least 340 / 1, or at least 350 / 1.

[0075] Model polymer spheres containing monodisperse polymer nanospheres can yield metal oxide spheres with similar diameter pores once the polymer is removed.

[0076] Without being bound by theory, it is believed that most spheres have a saturated color with reduced light scattering when the porosity and / or diameter and / or pore size of the spheres are within a specific range. These color characteristics are particularly important and can be adjusted depending on the desired intensity of light scattering on the skin, skin integument, and / or mucous membranes. In certain embodiments, it is preferred to have white spheres. The spheres according to the present invention allow for less light scattering and greater light reflection (haze) at lower dosages than prior art particles, and thus the average diameter of the spheres ranges from 4.5 μm to 9.9 μm, and / or the average diameter of the pores ranges from 50 nm to 500 nm, particularly from 100 nm to 400 nm, and more particularly from 220 nm to 300 nm.

[0077] The porous spheres according to the invention mainly comprise metal oxides. Advantageously, they consist essentially of metal oxides. Preferentially, they consist exclusively of metal oxides.

[0078] Preferentially, most of the porous spheres have a color that can be observed with the naked eye. One or more light absorbers can also be present in the spheres, thus making it possible to provide a more saturated observable color. Such absorbers can be added, for example, during the physical mixing of the spheres or can be included in the droplets before drying. Thus, the spheres according to the present invention do not have an observable color if they do not contain a light absorber, and have an observable color if a light absorber is added.

[0079] As a result, the spheres have the advantage that they can be used as colorants in cosmetic and / or dermatological compositions.

[0080] The porous spheres according to the present invention can have angle-dependent or angle-independent color. The term "angle-dependent color" means that the observed color depends on the angle of incident light or the angle between the observer and the observed color area. The term "angle-independent color" means that the observed color is substantially independent of the angle of incident light or the angle between the observer and the observed color area.

[0081] Spheres with angle-dependent color can be obtained in particular by using monodisperse polymer nanospheres, and also when a gentle step of drying the droplets is carried out to provide a polymer sphere model, thus allowing the polymer nanospheres to be aligned.

[0082] Spheres whose color is angle-independent can be obtained if the step of drying the droplets is carried out too quickly and does not allow the polymer nanospheres to align.

[0083] Thus, the porous spheres may contain, for example, 60% to 99.9% by weight of metal oxide and 0.1% to 40% by weight of light absorber relative to the total weight of the spheres. According to one embodiment of the present invention, the spheres contain 0.3%, preferentially 0.5%, preferentially at least 1%, and more preferentially at least 5% by weight of light absorber relative to the total weight of the spheres.

[0084] According to an alternative and preferred embodiment, the spheres do not contain any light absorbing agent, and the cosmetic compositions containing them also do not contain any light absorbing agent.In particular, light absorbing agents such as TiO2 may have certain toxicity.The present inventors have surprisingly found that even without any light absorbing agent, the spheres according to the present invention can have an immediate radiance effect and imperfection masking effect on the skin, or have an anti-blue light filter booster effect due to their ability to scatter sunlight and / or blue light.

[0085] Advantageously, the light absorber(s) are selected from the group consisting of organic and inorganic pigments that are compatible for cosmetic and / or dermatological use, in particular compatible with the skin, mucous membranes and / or skin integument.

[0086] Advantageously, the porous spheres are also themselves monodisperse.

[0087] According to the present invention, "particle size" is synonymous with "particle diameter" and is determined, for example, by scanning electron microscopy (SEM) or transmission electron microscopy (TEM). The term "mean particle size" (or mean diameter) refers to the D50, meaning that half of the population is below this size and the other half is above this size. This particle size is the size of the primary particles and can be measured by laser light scattering techniques on dispersions or dry powders.

[0088] Mercury porosimetry analysis is used to characterize the porosity of spheres. Mercury porosimetry consists of applying a controlled pressure to a sample immersed in mercury. The external pressure is applied so that the mercury penetrates the pores / holes of the material. The amount of pressure required is inversely proportional to the size of the pores / holes. In this way, mercury porosimetry provides the volume and size distribution of the pores. Mercury porosimetry generates the volume and pore size distribution using the Washburn equation from the pressure data versus the intrusion data generated by the instrument. Thus, for example, porous silica spheres contain pores with an average diameter of 165 nm and have an average porosity of 0.8.

[0089] The term "majority of spheres" refers to a population of spheres. This population can be in an amount of ≧0.1 mg, ≧0.2 mg, ≧0.3 mg, ≧0.4 mg, ≧0.5 mg, ≧0.7 mg, ≧1.0 mg, ≧2.5 mg, ≧5.0 mg, ≧10.0 mg, or ≧25.0 mg. The majority of spheres may be free of other compounds.

[0090] The term "having a color observable with the naked eye" means a color that is observable by most people. This means that the color is observable on a given surface, e.g., within 1 cm 2 , 2cm 2 , 3cm 2 , 4cm 2 , 5cm 2 , 6cm 2 , 7cm 2, 8cm 2 , 9cm 2 , 10cm 2 , 11cm 2 , 12cm 2 , 13cm 2 , 14cm 2 or 15cm 2 The color of the object can be of a sample of spheres distributed on a surface. This can also mean that the object can be viewed according to the CIE 1931 2° viewing standard and / or according to the CIE 1964 10° viewing standard. The color viewing background can be of different types, for example, white, black, or any intermediate color between black and white.

[0091] The term "micrometer-sized" or "micro-" refers to a size of about 1 μm to about 999 μm. The term "nanometer-sized" or "nano-" refers to a size of about 1 nm to about 999 nm.

[0092] The term "monodisperse" refers to a population of porous spheres or nanospheres of polymer particles having a uniform shape and diameter. Thus, a population of spheres is said to be monodisperse if 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% of the particles by number have diameters within ±7%, ±6%, ±5%, ±4%, ±3%, ±2%, or ±1% of the average diameter of the population of spheres.

[0093] Removal of the monodisperse population of polymer nanospheres results in metal oxide spheres with a population of pores having an average diameter.

[0094] Thus, the spheres comprising metal oxide according to the invention are prepared by a method comprising the following steps: - forming a liquid dispersion of polymer nanoparticles and metal oxide nanoparticles; - forming droplets of the dispersion; - drying the droplets of spheres comprising polymer nanospheres and metal oxide; - removing the polymer nanospheres from the model spheres to provide porous metal oxide spheres.

[0095] According to an advantageous embodiment, the droplets are aqueous. According to an alternative embodiment, the droplets are oily.

[0096] According to a preferred embodiment, the method comprises a continuous phase and mixing a liquid dispersion with the continuous phase to form an emulsion comprising dispersed droplets of the liquid dispersion. According to a particular embodiment, the continuous phase is oily and mixing is carried out between the continuous oily phase and the aqueous liquid dispersion to form a water-in-oil emulsion comprising aqueous droplets.

[0097] According to an alternative embodiment, the continuous phase is aqueous and mixing is carried out between the continuous aqueous phase and the oily liquid dispersion to form an oil-in-water emulsion containing lipid droplets.

[0098] According to an advantageous embodiment, the method comprises the subsequent steps of collecting the droplets, drying the droplets and removing the polymer nanospheres from the spherical model.

[0099] Advantageously, the polymeric nanoparticles have an average diameter of 50 nm, 75 nm, 100 nm, 130 nm, 160 nm, 190 nm, 210 nm, 240 nm, 270 nm, 300 nm, 330 nm, 360 nm, 390 nm, 410 nm, 440 nm, 470 nm, 500 nm, 530 nm, 560 nm, 590 nm, 620 nm, 650 nm, 680 nm, 710 nm, 740 nm, 770 nm, 800 nm, 830 nm, 860 nm, 890 nm, 910 nm, 940 nm, 970 nm or 990 nm.

[0100] Preferentially, the polymer is selected from the group consisting of poly(meth)acrylic acid, poly(meth)acrylate, polystyrene, polyacrylamide, polyethylene, polypropylene, polylactic acid, polyacrylonitrile, and also their derivatives and salts, copolymers, and combinations thereof. Preferentially, the polymer is selected from the group consisting of polystyrene, for example polystyrene / acrylic acid, polystyrene / poly(ethylene glycol) methacrylate, or polystyrene / styrene sulfonate copolymers.

[0101] According to a preferred embodiment, the metal oxide is selected from the oxides silica, titania, alumina or zirconia, cerium oxide, iron oxide, zinc oxide, indium oxide, tin oxide, chromium oxide, mixed metal oxides and combinations thereof. Preferentially, the metal oxide is an oxide of silica, titania or alumina or a combination thereof.

[0102] Advantageously, the porous spheres comprise between 60% and 99.9% by weight of metal oxide, preferentially at least 70%, more preferentially at least 80%, more preferentially at least 90%, and even more preferentially 99.9% by weight of metal oxide, relative to the total weight of the spheres.

[0103] According to an advantageous and preferential embodiment, the porous spheres have an average diameter of 0.5 μm to about 100 μm, advantageously 1 μm to 100 μm, in particular 4.5 μm to 9.9 μm, an average porosity of 0.10 to 0.90, or 0.10 to 0.80, and an average pore size of 50 nm to 999 nm, advantageously 50 nm to 500 nm, in particular 100 nm to 400 nm, more particularly 220 nm to 300 nm.

[0104] In a preferred embodiment, the porous spheres have an average diameter of 1 μm to 75 μm, preferentially 2 μm to 70 μm, preferentially 3 μm to 65 μm, 4 μm to 60 μm, 5 μm to 55 μm, or 5 μm to 50 μm, more preferentially 10 μm to 25 μm, in particular 4.5 μm to 9.9 μm. In an advantageous embodiment, they are microspheres, so that their average diameter is 1 μm to 100 μm, advantageously 1 to 20 μm, more advantageously 3 to 20 μm, even more advantageously 5 to 9 μm, in particular 4.5 μm to 9.9 μm, and even more advantageously 4 to 8 μm. Particularly advantageously, they are not nanospheres, in order to avoid penetration into the skin and to have a surface effect. The spheres according to the invention therefore advantageously remain on the surface of the skin.

[0105] In a preferred embodiment of the invention, the porous spheres have an average porosity selected from the following: 0.10, 0.12, 0.14, 0.16, 0.18, 0.20, 0.22, 0.24, 0.26, 0.28, 0.30, 0.32, 0.34, about 0.36, 0.38, 0.40, 0.42, 0.44, 0.46, 0.48, 0.50, 0.52, 0.54, 0.56, 0.58, 0.60, 0.62, 0.64, 0.66, 0.68, 0.70, 0.72, 0.74, 0.76, 0.78, 0.80 or 0.90.

[0106] According to alternative embodiments of the present invention, the porous spheres have an average diameter selected from 1 μm to 75 μm, 2 μm to 70 μm, 3 μm to 65 μm, 4 μm to 60 μm, 5 μm to 55 μm, 5 μm to 50 μm; for example, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm or 25 μm.

[0107] In a preferred embodiment of the invention, the porous spheres have an average pore size of about 50 nm to about 999 nm, advantageously 50 nm to 500 nm, in particular 100 nm to 400 nm, more particularly 220 nm to 300 nm, and even more particularly the following: 50 nm, 60 nm, 70 nm, 80 nm, 100 nm, 120 nm, 140 nm, 160 nm, 180 nm, 200 nm, 220 nm, 240 nm, 260 nm, 280 nm, 300 nm, 320 nm, 340 nm, 360 nm, 380 nm, 390 nm, 400 nm, 410 nm, 420 nm, 430 nm, 440 nm, 450 nm, 460 nm, 470 nm, 480 nm, 490 nm, 500 nm, 510 nm, 520 nm, 530 nm, 540 nm, 550 nm, 560 nm, 570 nm, 580 nm, 590 nm, 600 nm, 610 nm, 620 nm, 630 nm, 640 nm, 650 nm, 660 nm, 670 nm, 680 nm, 690 nm, 700 nm, 710 nm, 720 nm, 730 nm, 740 nm, 750 nm, 760 nm, 770 nm, 780 nm, 790 nm, 800 nm, 810 nm, 820 nm, 830 nm, 840 nm, 850 nm, 860 nm, 870 nm, 880 nm, 890 nm, 900 nm, 910 nm, 9 nm, 300 nm, 320 nm, 340 nm, 360 nm, 380 nm, 400 nm, 420 nm, 440 nm, 460 nm, 480 nm, 500 nm, 520 nm, 540 nm, 560 nm, 580 nm, 600 nm, 620 nm, 640 nm, 660 nm, 680 nm, 700 nm, 720 nm, 740 nm, 760 nm, 780 nm or 800 nm.

[0108] In an alternative embodiment, the porous spheres according to the invention have an average diameter selected from 4.5 μm, 4.8 μm, 5.1 μm, 5.4 μm, 5.7 μm, 6.0 μm, 6.3 μm, 6.6 μm, 6.9 μm, 7.2 μm, 7.5 μm, 7.8 μm, 8.1 μm, 8.4 μm, 8.7 μm, 9.0 μm, 9.3 μm, 9.6 μm or 9.9 μm; and 0.45, 0.47, 0.49, 0.5 an average porosity selected from: 0.1, 0.53, 0.55, 0.57, 0.59, 0.61, about 0.63, or 0.65; and an average pore diameter selected from: 220 nm, 225 nm, 230 nm, 235 nm, 240 nm, 245 nm, 250 nm, 255 nm, 260 nm, 265 nm, 270 nm, 275 nm, 280 nm, 285 nm, 290 nm, 295 nm, or 300 nm.

[0109] According to a particular embodiment of the present invention, the porous spheres have an average diameter of 4.5 μm to 9.9 μm, an average porosity of 0.45 to 0.65, and an average pore size of 220 nm to 300 nm.

[0110] According to a particular embodiment of the invention, the porous spheres according to the invention do not comprise on their surface a coating layer comprising a polyorganosiloxane, in particular a silicone compound.

[0111] In an advantageous embodiment, the porous spheres according to the invention do not comprise a coating layer on their surface comprising a hydrophobic compound. In a particularly advantageous embodiment, the porous spheres according to the invention do not comprise a coating layer on their surface.

[0112] According to the invention, the porous spheres can be used alone, in particular in powder form (100%), or in the form of a composition, in particular a cosmetic composition, in an amount of 1 x 10 1% by weight relative to the total weight of the composition. -3 ~100% by weight, advantageously 1x10 -2 It is used in a concentration of up to 95% by weight, preferably 0.01% by weight to 80% by weight, more preferentially 0.05% by weight to 50% by weight, preferentially 0.1% by weight to 30% by weight, preferentially 20% by weight or less, more preferentially 10% by weight or less, and more preferentially 0.5% by weight to 5% by weight.

[0113] The porous spheres according to the invention can be used alone, in particular in the form of cosmetic active ingredients, or in compositions intended to be in contact with the skin, the skin integuments and / or mucous membranes, such as cosmetic compositions, preferentially cosmetic compositions intended for topical application.

[0114] The term "topical application" as used herein means the application of the porous spheres according to the invention, optionally in the form of an active ingredient and / or in the form of a composition, to the surface of the skin, including the scalp, the skin integument and / or the mucous membranes, in particular by direct application or by spraying.

[0115] The active ingredient and / or cosmetic composition comprising the porous spheres according to the invention is preferentially intended for the cosmetic care and / or treatment of the skin, including the scalp and also the skin integuments, preferentially the hair.

[0116] In another embodiment, the spheres according to the present invention may be incorporated into a cosmetic composition that also includes at least one cosmetically acceptable excipient.

[0117] For purposes of the present invention, the term "cosmetically acceptable" excipient means a topically acceptable compound and / or solvent, i.e., a compound and / or solvent that does not induce an undue allergic reaction, is non-toxic, and is not unstable when contacted with the skin, including the human scalp and skin integument, or equivalents thereof.

[0118] The cosmetic compositions according to the invention may be in the form conventionally used for topical application to the skin, including the scalp and the integumentary skin, for example in liquid or solid form or in the form of compressed liquids, in particular formulated in the form of aqueous or oily solutions, in particular lotions, creams, aqueous or oily gels, especially in bottles or tubes, in particular shower gels, shampoos, hair conditioners, milks, oils, emulsions, hydrogels, microemulsions or nanoemulsions, in particular oil-in-water or water-in-oil emulsions or multilayer or silicone-based emulsions, especially in glass or plastic bottles or measuring bottles, serums, lotions, or alternatively in the form of aerosols or sprays, vials, liquid or bar soaps, pastes, ointments, foams, masks, lacquers, patches, preferably liquid, pasty or solid anhydrous products, for example in the form of rods, in particular sticks, or in powder form, preferentially creams, serums or lotions.

[0119] The cosmetic composition may be a makeup product or a makeup-removing product. In particular, the cosmetic composition is selected from the group consisting of serums, lotions, creams, shampoos, hair conditioners, oils, milks, ointments, pastes, foams, emulsions, hydrogels, shower gels, masks, lacquers, sprays, and waxes; it is more preferably a cream, serum, or lotion. The cosmetic composition may also be a powder, in particular a makeup powder, a foundation stick, a beard care, an aftershave composition, and / or a hair removal composition. According to an advantageous embodiment, the cosmetic composition according to the invention is at least slightly gelled and / or comprises an oil phase, and is more preferably an oily composition type, or an oil-in-water or water-in-oil emulsion or lotion type cosmetic composition.

[0120] The compositions according to the invention may comprise any suitable solvent and / or any suitable vehicle and / or any suitable excipient, optionally in combination with other compounds of interest.

[0121] Consequently, for these compositions, the excipients include, for example, at least one compound selected from the group consisting of preservatives, emollients, emulsifiers, surfactants, moisturizers, thickeners, conditioning agents, matting agents, stabilizers, antioxidants, texturing agents, glossing agents, film formers, solubilizers, pigments, colorants, fragrances, and sunscreens.These excipients are preferably selected from the group consisting of amino acids and derivatives thereof, polyglycerols, esters, cellulose polymers and derivatives, lanolin derivatives, phospholipids, lactoferrin, lactoperoxidase, sucrose-based stabilizers, vitamin E and derivatives thereof, natural and synthetic waxes, vegetable oils, triglycerides, unsaponifiables, plant sterols, vegetable esters, silicones and derivatives thereof, protein hydrolysates, jojoba oil and derivatives thereof, fat-soluble / water-soluble esters, betaine, amine oxides, plant extracts, sucrose esters, titanium dioxide, glycine and parabens, more preferably butylene glycol, steareth-2, steareth-21, glycol-15 stearyl ether, cetearyl alcohol, phenoxyethanol, methylparaben, ethylparaben, propylparaben, butylparaben, butylene glycol, natural tocopherols, glycerol, dihydroxycetyl sodium phosphate, isopropyl hydroxybenzoate, hydroxybenzoates ... Roxycetyl Ether, Glycol Stearate, Triisononanoin, Octyl Cocoate, Polyacrylamide, Isoparaffin, Laureth-7, Carbomer, Propylene Glycol, Glycerol, Bisabolol, Dimethicone, Sodium Hydroxide, PEG-30 Dipolyhydroxystearate, Caprylic / Capric Triglyceride, Cetearyl Octanoate, Dibutyl Adipate, Grapeseed Oil, Jojoba Oil, Magnesium Sulfate, EDTA, Cyclomethicone, Xanthan Gum The ingredient(s) is selected from the group consisting of: tung gum, citric acid, sodium lauryl sulfate, mineral wax and mineral oil, isostearyl isostearate, propylene glycol dipelargonate, propylene glycol isostearate, PEG-8, beeswax, glycerides derived from hydrogenated palm oil, glycerides derived from hydrogenated palm oil, lanolin oil, sesame oil, cetyl lactate, lanolin alcohol, castor oil, titanium dioxide, lactose, sucrose, low density polyethylene, and isotonic saline solution.

[0122] Many cosmetically active ingredients are known to those skilled in the art for improving the appearance of skin. Those skilled in the art know how to formulate cosmetic or dermatological compositions to achieve optimal results. Furthermore, the compounds described in this invention may have synergistic effects when combined with each other. These combinations are also encompassed by the present invention. The CTFA Cosmetic Ingredient Handbook, Second Edition (1992), describes various cosmetic and pharmaceutical ingredients commonly used in the cosmetic and pharmaceutical industries that are particularly suitable for topical use. Examples of these classes of ingredients include, but are not limited to, the following compounds: abrasives, absorbents, compounds for aesthetic purposes such as fragrances, pigments, colorants, essential oils, astringents, anti-acne agents, antiflocculant agents, anti-foaming agents, antibacterial agents (e.g., iodopropyl butylcarbamate), antioxidants, binders, biological additives, buffers, bulking agents, chelating agents, additives, biocidal agents, denaturants, thickeners, and vitamins and their derivatives or equivalents, film formers, polymers, opacifiers, pH conditioning agents, reducing agents, bleaching or whitening agents (e.g., hydroquinone, kojic acid, ascorbic acid, magnesium ascorbyl phosphate, ascorbyl glucosamine), conditioning agents (e.g., moisturizers).

[0123] Particularly advantageously, the spheres according to the invention may be used, optionally in cosmetic or pharmaceutical compositions, preferentially in dermatological compositions, as sole agents for improving the appearance, in particular the non-aesthetic symptoms and / or comfort of the skin, the skin integument and / or the mucous membranes, or in combination with other active agents having the same or complementary properties and which are customary in cosmetic or dermatological compositions, such as those selected from: moisturizing agents: one or more moisturizing promoters, for example agents chosen from the polysaccharide extracted from Cassia angustifolia seeds, sold by the applicant under the name Hyalurosmooth™, or a combination comprising pullulan, sodium hyaluronate and sodium alginate, sold by the applicant under the name PatcH2O™, or one or more compounds of natural moisturizing factors or natural extracts of honey, sold by the applicant under the name Melhydran™, and / or compounds of the glucosylglyceride family, in particular hexosylglycerides, which are extracts of the peel of Litchi cinensis, sold by the applicant under the name Litchiderm™; agents for stimulating fibronectin synthesis, in particular corn extracts, such as the extract sold in particular under the name Deliner™ by the Applicant: - agents for protecting the fibroblast growth factor (FGF2) of the extracellular matrix from its degradation and / or denaturation, in particular an extract of Hibiscus abelmoscus, as described in the patent application in the name of the Applicant filed under French patent application no. FR 0 654 316, and / or agents for stimulating fibroblast growth, such as an extract of fermented soybean containing known peptides under the name Phytokine™, sold by the Applicant and also described in patent application EP 1 119 344 B1 (Laboratoires Expanscience), and preferentially a combination of these two extracts; - agents for stimulating laminin synthesis, in particular extracts of biotechnologically modified malt (such extracts are in particular sold by the applicant under the name Basaline®); and agents for stimulating lipid synthesis, for example extracts of biotechnologically modified potato (Solanum tuberosum), sold by the applicant under the name Lipidessence®; - agents for stimulating the expression and / or activity of hyaluronan synthase 2 (HAS2), such as plant extracts described in patent application FR2 893 252 A1, in particular the aqueous extract of galanga (Alpinia galanga) sold by the applicant under the trademark Hyalufix®; - agents for stimulating the synthesis of lysyl oxidase, such as lysyl oxidase analogues (LOXL), for example as described in patent application FR 2 855 968, and in particular the dill extract sold by the applicant under the name Lys'lastine™; - one or more antifouling agents, such as the extract of Argania spinosa leaves sold by the applicant under the name Arganyl™, or the extract of Moringa oleifera seeds sold by the applicant under the name Purisoft™, or the extract of Eperua falcata roots sold by the applicant under the name Eperuline™; - agents for stimulating intracellular ATP synthesis, in particular extracts of the alga Laminaria digitata; - general anti-aging agents, especially those effective against pigmentation marks, in particular niacinamide or vitamin B3; antibacterial and / or sebum-regulating and / or sebum-absorbing agents, such as, for example, retinoids, sarcosine, zinc salts, in particular zinc gluconate or zinc salicylate, azelaic acid and / or derivatives and mixtures thereof, the extract of Orthosiphon stamineus sold by the applicant under the name MAT XS™ Bright, the extract of Bixa orellana sold by the applicant under the name Bix'Activ™, the antibacterial extracts described in patent application FR 2 863 893, in particular the Bordeaux extract, in particular the product sold by the applicant under the name Betapur™, or talc, - and mixtures thereof.

[0124] The use of porous spheres according to the invention is particularly advantageous insofar as it allows an immediate and sustained action on any type of skin, including for example the scalp, on the skin integument, preferentially on the hair, and on mucous membranes, in particular on skin that shows unaesthetic symptoms or signs of discomfort.

[0125] Preferentially, the porous spheres according to the invention, preferentially in the form of a cosmetic composition according to the invention, are applied to at least one area of ​​the body where the unaesthetic and / or unpleasant symptoms are present, this area or these areas being preferentially body surfaces chosen from the skin of the face, such as the forehead, cheeks, nose, temples, T-area (forehead, nose and chin), under the eyes, the periorbital area, in particular the area under the eyes, the chin, scalp, neck, back, shoulders, forearms, chest, hands, hair, beard, eyelashes, eyebrows and / or chest, in particular the legs, feet, armpits, hands, neck, nape, abdomen, arms, thighs, thighs, buttocks, hips, trunk, back, face and / or scalp, lip contour and hair, etc.

[0126] The subject of the present invention is therefore also a cosmetic care method comprising the topical application of porous spheres according to the invention to at least one area of ​​the skin and / or skin integument, in particular the hair, at least one surface chosen from the surfaces of the body, preferentially chosen from the skin of the face, such as the forehead, cheeks, nose, temples, T-area (forehead, nose and chin), under the eyes, the periorbital area, in particular the area under the eyes, the chin, scalp, neck, back, shoulders, forearms, chest, hands, hair, beard, eyelashes, eyebrows and / or chest, in particular the legs, feet, armpits, hands, neck, nape, belly, arms, thighs, buttocks, hips, trunk, back, face and / or scalp, lip contour and hair, etc.

[0127] The spheres according to the invention are particularly suitable for their use on any type of skin, mucous membranes and / or integument, in particular on Caucasian, Asian or African skin, but also on skin of any nature, in particular on sensitive skin, skin prone to atopic dermatitis, oily skin and sensitive skin. They are particularly suitable for masking the first unaesthetic symptoms of ageing, in particular the first wrinkles and / or mature skin, i.e. on the skin of men and women at least 50 years old, in particular menopausal women.

[0128] The cosmetic composition according to the invention is preferentially a no-rinse cosmetic composition.

[0129] Advantageously, the porous spheres according to the invention, preferentially in the form of a composition intended for topical application, preferentially a cosmetic composition according to the invention, are used in regular topical application, preferentially at least once a day, advantageously twice a day. Preferentially, the cosmetic composition is applied to the skin.

[0130] The spheres can be used in powder form, but can also be used in the form of cosmetic ingredients formulated in liquid form.To formulate them as cosmetic ingredients, the spheres are then preferably suspended in glycerol and / or another, particularly polar, solvent, such as water, alcohols, especially propanediol, glycols, especially butylene glycol, propylene glycol, polyols, or mixtures thereof, preferably water-glycol mixtures, more preferably water-glycol mixtures containing glycols selected from butylene glycol, propylene glycol, caprylyl glycol, hexylene glycol, and mixtures thereof.Particularly preferably, the spheres according to the invention are suspended in an aqueous solution containing glycerol, hexylene glycol, caprylyl glycol, or mixtures thereof.

[0131] Advantageously, the subject of the present invention is also a cosmetic treatment method for improving the appearance of the skin and / or skin integument, preferentially the hair, and / or for improving the comfort of the person who needs / wants it, comprising the following steps: - identifying in a person areas of the skin whose appearance and / or comfort should be improved and / or areas of the skin that exhibit unaesthetic conditions that should be concealed; and - a cosmetic composition comprising spheres according to the invention in an amount effective to improve the appearance and / or comfort of said areas of the skin and / or skin integument, preferentially of the hair, advantageously in an amount of 1 x 10% by weight relative to the total weight of the composition; -3 ~100% by weight, advantageously 1x10 -2 topically applying to said area of ​​skin a sphere content of up to 95% by weight, preferably 0.01% to 80% by weight, more preferentially 0.05% to 50% by weight, preferentially 0.1% to 30% by weight, preferentially not more than 20% by weight, more preferentially not more than 10% by weight and even more preferentially 0.5% to 5% by weight, The method also includes the above.

[0132] The spheres according to the invention can also be used to improve the comfort of affected skin, mucous membranes and / or skin integuments.

[0133] The skin, mucous membranes and / or skin integument are preferentially compromised, in particular with respect to conditions selected from the group consisting of reactive skin, inflamed skin, atopic skin, acne, psoriasis, herpes, boils, folliculitis, abscesses, impetigo, ecthyma, erysipelas, wounds and / or acne scars, and / or any combination thereof.

[0134] In a preferred embodiment of the invention, the spheres according to the invention are in the form of a pharmaceutical composition which also comprises a pharmaceutically acceptable excipient, in which the spheres are present in an amount of 1 x 10 -3 ~100% by weight, advantageously 1x10 -2It is present in a sphere content of up to 95% by weight, preferably 0.01% to 80% by weight, more preferentially 0.05% to 50% by weight, preferentially 0.1% to 30% by weight, preferentially not more than 20% by weight, more preferentially not more than 10% by weight and more preferentially 0.5% to 5% by weight.

[0135] For other purposes, the features and advantages of the present invention will become apparent to those skilled in the art on reading the illustrative description, which refers to embodiments given purely by way of illustration and in no way limiting the scope of the invention.

[0136] The examples form an integral part of the present invention, and any features that are believed to be novel over any prior art from the description taken as a whole, including the examples, form an integral part of the present invention in their function and general nature. Accordingly, each example has a general range. Furthermore, in the examples, all percentages are given by weight, temperatures are expressed in degrees Celsius unless otherwise indicated, and pressures are given in atmospheres unless otherwise indicated. [Example]

[0137] Example Example 1: Porous silica spheres A copolymer of styrene and acrylic acid is prepared as follows: 230 mL of deionized water is added to a three-necked reaction flask equipped with a thermometer, a condenser, and a magnetic stirrer under a nitrogen atmosphere. The water is heated to 80°C, and 10 g of styrene is added with stirring, followed by 100 mg of acrylic acid dissolved in 10 mL of deionized water via a syringe. 100 mg of ammonium persulfate is dissolved in 10 mL of deionized water and added to the mixture with stirring via a syringe. The mixture is left stirring at 80°C for 24 hours. The colloidal polymer dispersion is cooled to room temperature and purified by centrifugation, thus forming polystyrene nanospheres with an average particle size of 250 nm. The colloidal aqueous dispersion of polystyrene is diluted to 1 wt% in deionized water, and 1 wt% of silica nanoparticles is added. The mixture is sonicated to prevent particle aggregation.

[0138] The continuous oily phase contains 0.1 wt % polyethylene glycol / perfluoropolyether surfactant in fluorinated oil.

[0139] The aqueous colloidal dispersion and oil are each injected via a syringe connected to a pump into a microfluidic device with a junction to obtain a droplet size of 50 µm. The assembly is allowed to equilibrate until monodisperse droplets are generated. These droplets are then collected.

[0140] The collected droplets are then dried in an oven at 45°C for 4 hours to obtain monodisperse spherical models. These polymer model spheres are then placed on a silicone plate and baked by heating from room temperature to 500°C over 3 hours, and then maintaining the temperature at 500°C for 2 hours. The spheres are then cooled to room temperature for 3 hours. The monodisperse spheres thus obtained have an average diameter of 15 microns.

[0141] According to an alternative embodiment, Example 1 can be repeated and the drying step carried out by microwave irradiation, drying under vacuum and / or in the presence of a dehydrating agent.

[0142] Example 2: Variation of sphere colors A 0.5 mg quantity of porous spheres was placed on a 6 cm 2 Place the solution in a 10 mL clear glass flask with a base area of ​​1.5 mL. This color is observed with the naked eye.

[0143] Two porous sphere samples were prepared according to Example 1, in which the polymer / silica weight ratios were 1 / 1 and 3 / 1. The sample prepared with a 1 / 1 ratio was white, while the sample prepared with a 3 / 1 ratio had a blue color.

[0144] Another sample of porous silica spheres was prepared according to Example 1, in which the polystyrene nanospheres had an average particle size of 360 nm and a polymer / silica weight ratio of 3 / 1. The resulting sample had a green color.

[0145] Example 3: Porous silica titanium spheres A sample of porous spheres containing silica and titanium was prepared according to the method described in Example 1, in which the polymer / metal oxide weight ratio was 3 / 1. The silica / titanium weight ratio was 9 / 1.

[0146] Example 4: Color evaluation Spheres in an amount of 10 g obtained according to Example 1 on the one hand and 10 g obtained according to Example 3 on the other hand were evaluated by microscope, spread in powder form between a slide and a coverslip and illuminated in different directions. It was observed that the spheres reflected light, appeared shiny under the microscope and had different shades depending on the size of the sphere and the size of the pores.

[0147] The same experiment was carried out on a carbomer hydrogel type composition containing 1% by weight of spheres relative to the total weight of the composition.

[0148] Similarly, a pure oil type composition containing 1% by weight of spheres relative to the total weight of the composition was prepared and observed. Additionally, an oil-in-water type emulsion containing 1% by weight of spheres relative to the total weight of the composition was evaluated.

[0149] In addition to having excellent compatibility with aqueous and oily media, the spheres had a soft feel for topical application, especially in compositions containing oil (oil or emulsion).

[0150] Finally, under a microscope, it was observed that the spheres in the evaluated compositions reflect light in all directions, making it possible to improve the appearance of the skin, particularly by concealing unaesthetic conditions. This was confirmed in vitro in a biopsy model.

[0151] Example 5: Evaluation of the improvement in comfort due to the cosmetic composition according to the present invention The spheres obtained in Example 1 were incorporated into a simple carbomer-type hydrogel at 0.5% and 0.1% by weight relative to the total weight of the composition under vigorous stirring. The spheres are inert, do not reswell, and remain suspended in the medium. Vigorous stirring provides a superior dispersion by preventing agglomeration.

[0152] Similarly, spheres suspended at 0.05% by weight in water and at 0.05% by weight in vegetable oil are inert and do not reswell.

[0153] Similarly, the spheres were incorporated into a face care type emulsion at 1% by weight and evaluated by trained sensory analysts. They applied the emulsion containing the spheres to their forearms according to the prescribed procedure. From this evaluation, it is clear that the trained analysts reported that the emulsion containing the spheres of the present invention provided a thicker, oilier application sensation, observed a longer penetration of the cream into the skin, and observed a smooth finish. Finally, an extremely soft sensation on the skin was described, along with a slightly satiny effect on the skin. Thus, the spheres of the present invention improved skin comfort.

[0154] Example 6: Cosmetic composition according to the present invention The porous spheres used were the porous spheres in powder form obtained in Examples 1, 2 or 3.

[0155] Example 6a): Fluid Facial Emulsion

[0156] [Table 1]

[0157] The emulsion is prepared by the usual methods known to those skilled in the art by introducing phase B into phase A with stirring until it is completely dispersed. The mixture is heated to 75-80°C, and separately, phase C is also heated. Phase C is then added to the mixture with stirring. The mixture is allowed to cool to room temperature with gentle stirring, and the compounds of phases E and F are added one after the other. The whole is homogenized for 2 minutes. The pH is adjusted to 5.2.

[0158] Example 6b): Facial Cream

[0159] [Table 2]

[0160] This cream is prepared by conventional methods well known to those skilled in the art by mixing phases A and B, preheated to 75°C, and then adding phases C and D, while mixing and adjusting the composition with phase E to a pH of 6.2 and a viscosity of 15 000 mPa.s (measured in a Brookfield apparatus (RVT; 23°C, spindle TC; 20 rpm)).

[0161] Example 6c): Shampoo

[0162] [Table 3]

[0163] The shampoo is prepared by conventional methods well known to those skilled in the art by mixing the four phases and adjusting the composition to a pH of 5.2 and a viscosity of 2200 mPa.s (measured in a Brookfield apparatus (RVT; 23°C, spindle 5; 50 rpm)).

Claims

1. 1. Cosmetic use of porous spheres comprising a metal oxide to improve the appearance of the skin, skin integument, and / or mucous membranes by masking or concealing unaesthetic conditions of the skin, skin integument, and / or mucous membranes, comprising: the spheres rest on the surface of the skin and have an average diameter of 1 μm to 25 μm and an average pore size of 50 nm to 500 nm; The metal oxide is silica oxide, The porous spheres comprising said metal oxide are prepared using a sacrificial polymer model.

2. 2. The use according to claim 1, wherein the spheres have an average porosity of 0.10 to 0.

90.

3. 3. The use according to claim 1, wherein the spheres have an average porosity of between 0.10 and 0.

80.

4. The use according to any one of claims 1 to 3, wherein the spheres have an average diameter of between 4.5 μm and 9.9 μm.

5. The use according to any one of claims 1 to 4, wherein the spheres have an average pore size of from 100 nm to 400 nm.

6. 6. The use according to any one of claims 1 to 5, wherein the porous spheres comprise 60% to 99.9% by weight of metal oxide and 0.1% to 40% by weight of light absorber, relative to the total weight of the spheres.

7. The use according to any one of claims 1 to 6, wherein the spheres have an average porosity of between 0.45 and 0.

65.

8. 8. The use according to any one of claims 1 to 7, wherein the spheres have an average diameter of 4.5 μm to 9.9 μm, an average porosity of 0.45 to 0.65 and an average pore size of 220 nm to 300 nm.

9. Use according to any one of claims 1 to 8 for masking or concealing unaesthetic conditions of the skin, skin integuments and / or mucous membranes by optical effect.

10. Use according to any one of claims 1 to 9, characterized in that the non-aesthetic symptoms of the skin, skin integument and / or mucous membranes are selected from irregularities in the relief and / or texture of the skin, and irregularities in the skin colour.

11. Use according to any one of claims 1 to 10, characterized in that the non-aesthetic symptoms of the skin are non-aesthetic irregularities in the relief and texture of the skin selected from wrinkles and / or fine lines, raised points, blackheads, enlarged pores, a rough appearance, marks and scars.

12. Use according to any one of claims 1 to 11, characterized in that the non-aesthetic symptoms of the skin are skin colour irregularities selected from pigmentation marks, white or dark spots, age spots or hyper- or depigmented marks, melasma of pregnancy, moles, melanomas, freckles and rashes, loss of complexion radiance, dull complexion and / or dark circles and bags under the eyes.

13. The spheres are 1×10 based on the total weight of the composition -3 The use according to any one of claims 1 to 12, which is present in the cosmetic composition in a concentration of up to 100% by weight.

14. Use according to any one of claims 1 to 13, characterized in that the spheres are present in a cosmetic composition, the cosmetic composition being in the form of a serum, a lotion, a cream, a shampoo, a hair conditioner, an oil, a milk, an ointment, a paste, a foam, an emulsion, a hydrogel, a shower gel, a mask, a lacquer, a spray, a wax, a powder or a stick.

15. 15. The use according to claim 14, characterized in that the cosmetic composition comprises an oily phase.

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