FR3160105A1 - TINTED SUN COSMETIC COMPOSITION - Google Patents

Abstract

The invention relates to a tinted cosmetic sunscreen composition, in emulsion form, suitable for topical application to the skin, comprising water, the particulate sunscreen phenylene bis-diphenyltriazine, at least one emulsifier, at least one oily emollient, at least one pigment in a weight content of 1 to 5%, and a suspending agent selected from unmodified smectites in a weight content of 0.3 to 2%.

Description

TINTED SUN COSMETIC COMPOSITION

The present invention relates to a tinted sunscreen cosmetic composition comprising the particulate sunscreen phenylene bis-diphenyltriazine.

TECHNICAL CONTEXT

The field of photoprotection is a major public health issue to prevent skin damage from overexposure to the sun.

The potentially harmful effects of ultraviolet radiation on the skin are well known, and a multitude of sunscreen products, commonly referred to as sunscreens, are marketed to prevent these effects. Skin damage is mainly induced by ultraviolet radiation (UVA and/or UVB), but also by visible light, including high-energy visible blue light, and infrared via damage to macromolecules leading to lesions of deoxyribonucleic acid (DNA), oxidative stress, lipid peroxidation and degradation of the dermal matrix.

Among existing sunscreens, phenylene bis-diphenyltriazine is a particulate organic sunscreen (also called UV filter) with the particularity of absorbing and reflecting the harmful part of the solar spectrum, which includes UVB, short UVA, long UVA but also high-energy blue light (Bacqueville et al., Photochemical & Photobiological Sciences (2021) 20: 1475–1486). Its properties make it a particularly interesting sunscreen for the field of photoprotection and the prevention of photoaging.

Photoprotective systems combining phenylene bis-diphenyltriazine with other existing sunscreens have already been proposed by the prior art, and more particularly systems developed to optimize the number and total quantity of sunscreens in order to obtain better results in terms of tolerance and toxicity for the user, and reduce the environmental impact of sunscreen products (WO 2013/113745).

The phenylene bis-diphenyltriazine-based sunscreen compositions described and marketed to date are mainly emulsions, and more specifically oil-in-water emulsions. These compositions are available in untinted or lightly tinted form.

Pigments have become almost indispensable in cosmetics. They allow the compositions to be colored and give a unique dimension to the face thanks to their shade. Pigments are insoluble, particulate solid chemical substances that bring color and shade to the compositions that contain them. Many commercial materials are available and offer a wide range of colors, shades, reflections, etc. depending on their optical properties due to the nature of the pigment, its size, its coating, etc.

Tinted sunscreens combine sunscreens with a colored base traditionally made up of different preparations and concentrations of iron oxides and pigmented titanium dioxide, which can also optimize protection against visible light. To adapt to consumer demand while taking into account their skin phenotypes, tinted products of different shades are available. The tint is obtained by mixing the three iron oxides - yellow, red, and black - with pigmented titanium dioxide.

Iron oxides are pigments produced from iron sulfate. Depending on their oxidation state, they can appear yellow, red, or black. A yellow or red pigment appears as such due to the reflection of the corresponding wavelengths in the visible range. The black appearance of a pigment is due to absorption throughout the visible region, with no photons being reflected in this region. Depending on the desired shade, pigmentary titanium dioxide (i.e., titanium dioxide that is not nanosized) is another pigment that can be used to provide coverage and opacity. It appears white because it reflects all photons of visible light.

There is currently a need for new tinted sunscreen cosmetic compositions comprising the sunscreen of interest phenylene bis-diphenyltriazine and corresponding to a larger range of shades (including darker shades) than current tinted sunscreen compositions, so as to be able to respond to all skin phototypes. This may require incorporating a larger total quantity of pigments into the sunscreen compositions. The present invention aims to provide such tinted sunscreen cosmetic compositions, in particular of a darker shade than the tinted sunscreen cosmetic compositions of the prior art. Obtaining good covering power for such compositions is also one of the objectives of the present invention.

Added to this is the consumer attraction to light and fluid, non-sticky textures, which the invention also aims to satisfy.

In this context, having to suspend a larger quantity of particulate fillers – including the particulate sunscreen phenylene bis-diphenyltriazine – in an oil-in-water emulsion composition, the formulator will be faced with the risk of instability of the formula due to this large quantity of particulate fillers to be placed and maintained in suspension; and this is particularly the case when the particulate fillers are distributed in each of the two phases of the emulsion. A problem of instability in the formulation can result in particular in the migration and separation of pigments towards the surface of the composition, making it inhomogeneous and unsatisfactory.

The effectiveness of a composition in terms of sun protection requires ensuring a stable and homogeneous suspension of all the solid particles it contains in order to prevent any agglomeration of said particles. This objective must not be achieved to the detriment of:
- nor the desired fluidity of the compositions, which must have a sufficiently fluid texture to be compatible with application by the users' fingers, and therefore to be easy to spread,
- nor their sensory properties.

It has been discovered by the present inventors that the addition of unmodified smectite, and in a given specific quantity, in a cosmetic composition in the form of an oil-in-water emulsion, containing from 1 to 5% by weight of phenylene bis-diphenyltriazine, and pigments, makes it possible, whatever the quantity of these pigments in the composition, and including for quantities greater than 2% by weight (and remaining less than or equal to 5% by weight) relative to the total weight of the composition, to obtain the various benefits sought in terms of:
- stability of the composition and homogeneity of the suspension of the particulate charges contained therein,
- sensoriality / fluidity / coverage (the degree of coverage provided by the composition being linked to the quantity of pigments present in the composition),
- and sun protection factor (SPF).

DESCRIPTION OF THE INVENTION

Thus, according to a first aspect of the invention, there is provided a tinted cosmetic sunscreen composition in the form of an emulsion, suitable for topical application to the skin, said composition comprising, the percentages being expressed by weight relative to the total weight of the composition:
- 30 to 50% water,
- 1 to 5% of the particulate sunscreen phenylene bis-diphenyltriazine,
- at least one emulsifier,
- at least one oily emollient,
- at least one pigment, in particular of mineral origin, the total pigment content in the composition being between 1 and 5%, preferably between 2 and 5%, by weight relative to the total weight of the composition,
- and a suspending agent chosen from unmodified smectites, the total quantity of suspending agent(s) chosen from unmodified smectites in the composition being between 0.3 and 2% by weight relative to the total weight of the composition.

For the purposes of the present invention, the term "photoprotective system" means a combination of compounds which, after application to a surface (skin, hair, etc.), by mechanisms of absorption and/or reflection and/or diffusion of UVA and/or UVB radiation and/or blue light, prevent, or at least limit, the contact of said radiation with said surface.

The term "sunscreen" refers to a substance capable of filtering solar radiation to protect a surface, typically skin or hair, from the harmful effects of this radiation.

The term "ultraviolet radiation" or "UV radiation", commonly abbreviated "UV", refers to solar ultraviolet radiation but also to artificial ultraviolet radiation, generated by tanning lamps for example.

By "UVA radiation" or simply "UVA" is meant ultraviolet rays with a wavelength λ between 320 and 400 nm.

By "UVB radiation" or simply "UVB" is meant ultraviolet rays with a wavelength λ between 290 and 320 nm.

A sunscreen is called a “UVA filter” or “UVB filter” depending on whether it filters mainly UVA or UVB rays.

A so-called “broad band” or “broad spectrum” sun filter filters both UVA and UVB rays.

Depending on the radiation filtration mechanism, that is to say depending on whether the radiation is absorbed and/or reflected, or even diffused by the solar filter, we distinguish, strictly speaking:
- filters in the strict sense, which mainly absorb radiation, and
- screens, which absorb and reflect radiation.

However, in the remainder of the description, the term “solar filter”, sometimes abbreviated “filter”, will be used interchangeably to designate a filter or a screen.

A sunscreen can be “lipo-soluble” or “water-soluble”, depending on whether it dissolves more easily in lipids or in water, or “insoluble”. A non-soluble sunscreen is typically in particulate form, and can nevertheless be integrated into a sunscreen composition, in particular in a dispersed form, in particular hydrodispersed when it is dispersed in an aqueous phase.

In this description, the term “sun protection” also means protection against the effects of ultraviolet radiation, in particular UVA and/or UVB, and/or blue light. The expression “sun protection”, as used in this description, encompasses not only protection against the harmful effects of solar radiation, but also artificial ultraviolet radiation, generated by tanning lamps for example. More particularly, sun protection is understood here as preventing, or at least limiting, contact between ultraviolet radiation and/or blue light and the surface to be protected, by mechanisms of absorption and/or reflection and/or diffusion of UVA and/or UVB radiation and/or blue light.

Phenylenes bis-diphenyltriazine, the name commonly used to refer to 5,6,5’,6’-tetraphenyl-3,3’-(1,4-phenylene)-bis[1,2,4]triazine, (CAS No. 55514-22-2) is a sunscreen, more specifically an ultra-broad spectrum sunscreen capable of filtering the harmful part of the solar spectrum, which includes UV radiation (UVB and UVA), but also high-energy visible blue light. In the remainder of the description, the names 5,6,5’,6’-tetraphenyl-3,3’-(1,4-phenylene)-bis[1,2,4]triazine and phenylene bis-diphenyltriazine are used interchangeably.

Phenylenesis bis-diphenyltriazine is an organic particulate filter of the non-soluble, water-dispersible type.

This filter is typically in the form of an aqueous dispersion, comprising between 20% and 50%, in particular between 40% and 50%, by weight of active material relative to the total weight of the dispersion. Advantageously, the process for preparing such an aqueous dispersion consists of grinding the organic filter in the form of particles, using a grinding apparatus and in the presence of a grinding aid. Conventionally, wet grinding processes such as wet grinding or wet mixing, well known to those skilled in the art, are used for this purpose. The grinding apparatus may be, for example, a microbead mill, a vibrating mill or a ball mill. Depending on the grinding process, the grinding aid is chosen from the group consisting of anionic, non-ionic or amphoteric surfactants, emulsifiers and dispersants. Examples of such grinding aids include the dispersant PPG-1-PEG-9 Lauryl Glycol Ether (Eumulgin® L, marketed by BASF), which was used to prepare the aqueous dispersion that was the subject of the Scientific Committee on Consumer Safety (SCCS) final opinion SCCS/1594/18. In this aqueous dispersion comprising between 45 and 55% by weight of water:
- phenylene bis-diphenyltriazine is between 40 and 50%,
- PPG-1-PEG-9 Lauryl Glycol Ether is present at approximately 4.5%,
the % being expressed by weight relative to the total weight of the dispersion.

In particular embodiments of the invention, the size D50 of the phenylene bis-diphenyltriazine particles contained in the composition according to the invention is between 100 and 1000 nm, more particularly between 100 and 500 nm, even more particularly between 120 and 400 nm, in particular between 120 and 250 nm, in particular between 120 and 200 nm, typically between 150 and 200 nm.

The term “D50 size” or “median size” refers to the size for which the cumulative particle size distribution function is equal to 50%. The value of the D50 size can be determined using a Mastersizer 3000 laser diffraction particle size analyzer in wet conditions.

Phenylenese bis-diphenyltriazine represents between 1% and 5% by weight relative to the total weight of the composition. In particular embodiments of the invention, it represents between 2% and 5%, in particular between 2% and 4%, preferably between 3% and 4%, by weight relative to the total weight of the composition.

It is understood that these mass percentages, as well as all those indicated in this description, are expressed as a percentage of mass of active material relative to the total mass of the composition.

In the composition according to the present invention, phenylene bis-diphenyltriazine can be combined with one or more additional sun filters, to constitute a photoprotective system which allows, after application to a surface (skin, hair, etc.), by mechanisms of absorption and/or reflection and/or diffusion of UVA and/or UVB radiation, to prevent, or at least limit, the contact of said radiation with said surface.

Such additional sun filters are preferably chosen, and introduced into the composition in an adequate quantity, so that the composition according to the invention has a sun protection factor (SPF) of between 20 and 99, preferably between 30 and 80 and more preferably between 50 and 80.

The total SPF of the composition is classically assessed in itself, for wavelengths between 290 and 400 nm. Its value can be determined according to the method recommended by COLIPA (European Federation of Perfume Industries), in its guidelines published in March 2011.

In particular embodiments of the invention, the SPF of the composition is greater than or equal to 50, advantageously greater than or equal to 60.

In other particular embodiments, the SPF/UVA ratio is less than or equal to 3, in accordance with the regulations in force. The denominator of said quotient corresponds to the UVA portion (320 to 400 nm) of the total SPF, and can be calculated according to the method recommended by COLIPA (European Federation of Perfume Industries), in its directives published in March 2011. Advantageously, the SPF/UVA ratio of the composition according to the invention is less than or equal to 2.5.

In particular embodiments of the invention, the total quantity of additional sunscreens contained in the composition is between 3 and 19% by weight, preferably between 5 and 17% by weight, in particular between 7 and 15% by weight, and typically between 8 and 15% by weight, for example between 10 and 13% by weight, relative to the total weight of the composition.

In particular embodiments of the invention, the composition comprises at least one additional sunscreen.

At least one additional sunscreen may be chosen from those conventionally known, including organic sunscreens such as triazine derivatives, benzotriazole and phenyl benzotriazole derivatives, dibenzoylmethane derivatives, amino-substituted benzophenone and 2-hydroxybenzophenone derivatives, merocyanine derivatives, para-aminobenzoic acid derivatives, salicylic derivatives, cinnamic derivatives, β,β'-diphenylacrylate derivatives, benzylidene camphor derivatives, phenylbenzimidazole derivatives, anthranilic derivatives, imidazoline derivatives, and benzylmalonate derivatives.

Preferably, at least one additional sunscreen is chosen from triazine derivatives, benzotriazole and phenyl benzotriazole derivatives, dibenzoylmethane derivatives, amino-substituted benzophenone and 2-hydroxybenzophenone derivatives and merocyanine derivatives.

In particular advantageous embodiments of the invention, the tinted cosmetic composition does not, however, comprise ethylhexyl salicylate, octocrylene, ethylhexyl methoxycinnamate, isoamyl methoxycinnamate, homosalate, para-aminobenzoic acid (PABA), octyl dimethyl PABA, 3-methylbenzylidene-camphor, 4-methylbenzylidene-camphor, benzophenone-3 and/or benzophenone-4. Octocrylene, like ethylhexyl salicylate, are suspected of being potential endocrine disruptors. Other sunscreens present in many commercial products are also subject to controversy, due to their potentially harmful effects for the user or for the environment. Examples include cinnamate derivatives (ethylhexyl methoxycinnamate, isoamyl methoxycinnamate), homosalate, para-aminobenzoic acid (PABA, octyl dimethyl PABA), camphor (3-methylbenzylidene camphor, 4-methylbenzylidene camphor) or benzophenone (benzophenone-3, benzophenone-4). The use of such compounds is therefore not desirable.

Thus, in particular embodiments of the invention, the composition comprises at least one additional sunscreen, excluding ethylhexyl salicylate, octocrylene, ethylhexyl methoxycinnamate, isoamyl methoxycinnamate, homosalate, para-aminobenzoic acid (PABA), octyl dimethyl PABA, 3-methylbenzylidene-camphor, 4-methylbenzylidene-camphor, benzophenone-3 and/or benzophenone-4.

The composition according to the invention preferably contains, as an additional sun filter, at least one liposoluble organic sun filter.

Thus, in preferred embodiments of the invention, the tinted cosmetic composition comprises the phenylene bis-diphenyltriazine sunscreen/UV filter and at least one additional sunscreen, in particular a liposoluble organic sunscreen, in particular chosen from:
- hexyl 2-[4-(diethylamino)-2-hydroxybenzoyl]benzoate (CAS No.: 302776-68-7), also known as diethylamino hydroxybenzoyl hexyl benzoate or DHHB, in particular as marketed by BASF under the name Uvinul® A Plus, a liposoluble UVA filter with a maximum absorption wavelength λmax equal to 354 nm;
- 2,4-bis[4-(2-ethylhexyloxy)-2-hydroxyphenyl]-6-(4-methoxyphenyl)-1,3,5-triazine (CAS No. 187393-00-6), also known as bis-ethylhexyloxyphenol methoxyphenyl triazine or BEMT, in particular as marketed by BASF under the name Tinosorb® S, a liposoluble broadband filter, having two absorption peaks at 310 nm and 340 nm;
- diethylhexyl butamido triazone, or DBT (chemical name: 4,4'-[[6-[[4-[[(1,1-dimethylethyl)amino]carbonyl]phenyl]amino]-1,3,5-triazine-2,4-diyl]diimino]bis-, bis(2-ethylhexyl)benzoate; CAS No.: 154702-15-5), in particular as marketed by 3V Sigma under the name Uvasorb® HE, a fat-soluble UVB filter, having a maximum absorption wavelength λmax equal to 310 nm;
- ethylhexyl triazone or EHT (chemical name: 4-[[4,6-bis[[4-(2-ethylhexoxy-oxomethyl)phenyl]amino]-1,3,5-triazin-2-yl]amino]benzoic acid 2-ethylhexyl ester; CAS No.: 88122-99-00), in particular as marketed by BASF under the name Uvinul® T 150, a fat-soluble UVB filter, having a maximum absorption wavelength λmax equal to 314 nm;
- and butyl methoxydibenzoylmethane, or 4-tert-butyl-4-methoxydibenzoylmethane (chemical name: 1,4-(1,1-dimethylethyl)phenyl-3-(4-methoxyphenyl)-1,3-propanedione; CAS No.: 70356-09-1), also known as avobenzone or BMDBM, in particular as marketed by DSM under the name Parsol® 1789, a liposoluble UVA filter, having a maximum absorption wavelength λmax equal to 357 nm;
- or any of their mixtures.

In preferred embodiments of the invention, the tinted cosmetic composition comprises the UV filter phenylene bis-diphenyltriazine and at least one liposoluble sunscreen chosen from:
- hexyl 2-[4-(diethylamino)-2-hydroxybenzoyl]benzoate;
- 2,4-bis[4-(2-ethylhexyloxy)-2-hydroxyphenyl]-6-(4-methoxyphenyl)-1,3,5-triazine;
- diethylhexyl butamido triazone;
- and ethylhexyl triazone;
or any of their mixtures.

In particular, the cosmetic composition according to the invention comprises the following additional sunscreens, preferably to the exclusion of any other (except phenylene bis-diphenyltrazine, always present in the composition according to the invention):
- diethylamino hydroxybenzoyl hexyl benzoate,
- bis-ethylhexyloxyphenol methoxyphenyl triazine, and
- ethylhexyl triazone or diethylhexyl butamido triazone

A number of sunscreens are not sufficiently photostable, that is to say they tend to degrade during prolonged exposure to ultraviolet radiation, and therefore no longer provide sufficient protection for the user. It is particularly well known that the butyl methoxydibenzoylmethane molecule, a UVA filter widely used in commercial sunscreen products, cleaves into different chemical constituents lacking absorbing capacity when it is subjected to UV irradiation, if it is not combined with other compounds making it possible to improve its photostability. Consequently, preferably, the tinted cosmetic composition according to the invention is free of butyl methoxydibenzoylmethane.

In particular embodiments of the invention, the tinted cosmetic composition does not comprise any water-soluble sunscreen. Alternatively, it may contain at least one water-soluble organic sunscreen, such as phenylbenzimidazole sulfonic acid.

In particular embodiments of the invention, the tinted cosmetic composition further comprises at least one particulate organic sunscreen, in particular chosen from the following filters:
- methylene bis-benzotriazolyl tetramethylbutylphenol (chemical name: 2,2'-methylene-bis-(6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol; CAS No.: 103597-45-1), also known as MBBT, in particular as marketed by BASF under the name Tinosorb® M;
- and 2,4,6-tris(biphenyl-4-yl)-1,3,5-triazine (CAS no.: 31274-51-8), also called trisbiphenyl triazine or TBPT, in particular as marketed by BASF under the name Tinosorb® A2B;
or it contains one of their mixtures.

In other particular embodiments, the composition according to the invention is free of such particulate organic sunscreens.

At least one additional sunscreen can be chosen from those conventionally known, including inorganic sunscreens such as coated or uncoated metal oxides, such as titanium, iron, zinc, zirconium, or cerium oxides. These inorganic filters are insoluble and come in particulate form.

In other particular embodiments, the composition according to the invention is free of such inorganic sunscreens.

It is important to differentiate between titanium dioxide as used as a sunscreen/UV filter and titanium dioxide in its pigment form. Titanium dioxide can take several different forms, each with different properties. The main difference between titanium dioxide UV filter and titanium dioxide pigment is the particle size, with the pigment particle size being significantly larger than the UV filter.

Nano-sized titanium dioxide, smaller than 200 nm, which should be considered synonymous with “titanium dioxide UV filter,” is present in the majority of physical sunscreens due to its high UV absorption capabilities and resistance to fading under ultraviolet light. This advantage enhances its stability and ability to protect the skin from UV radiation. Nano-sized titanium dioxide particles are primarily used in sunscreen compositions since they scatter visible light much less than titanium dioxide pigments and can provide UV protection.

Titanium dioxide pigment, which is larger than 200 nm, is the most widely used white pigment due to its brightness and very high refractive index, in which it is surpassed only by a few other materials. The crystal size of titanium dioxide pigment can even reach a micrometer scale, such as around 7000 nm (measured by electron microscopy) to optimize the maximum reflection of visible light. Titanium dioxide pigment is also an effective opacifier in powder form, in which form it is used as a pigment to provide whiteness and opacity to products such as paints, plastics, foods, medicines and most toothpastes. Titanium dioxide pigment is able to scatter light, making it very useful for pigments.

More generally, in this description, "pigments" are understood to mean mineral or organic particles, natural or synthetic, coated or not, insoluble and coloring. As indicated above, the definition of pigments includes titanium dioxide with a particle size greater than 200 nm. Pigments are generally in powder form or in pre-dispersed form in an aqueous or oily solution.

The pigment(s) used in the composition according to the invention give the latter its color and contribute to its covering power, that is to say its capacity to cover and mask the imperfections of the area of skin to which it is applied.

This or these pigments are preferably, but not limited to, of the mineral type.

In preferred embodiments of the invention, the composition according to the invention contains one or more pigments, in particular mineral pigments, which are preferably chosen from iron oxides and titanium dioxide, or one of their mixtures. Preferably, the composition according to the invention contains a mixture of pigments, this mixture of pigments comprising, and preferably consisting of, yellow, red and black iron oxides, and titanium dioxide. Such a mixture of pigments alone makes it possible, quite advantageously, to adapt to a wide range of skin tones, by an adequate choice of their respective proportions.

In preferred embodiments, the composition according to the invention does not comprise any pigment other than iron oxides and titanium dioxide.
In particular, the composition according to the invention is preferably free of natural or synthetic mica (fluorphlogopite).

Mineral pigments are referenced by a color index (CI) in the INCI nomenclature (International Nomenclature of Cosmetic Ingredients), the main pigments used in cosmetics/makeup being the following:
- CI 77891 White (Titanium Dioxide)
- CI 77491 Red (Iron Trioxide)
- CI 77492 Yellow (Iron Oxide)
- CI 77499 Black (Iron Tetroxide)
- CI 77007 Blue (Lazurite)
- CI 77742 Violet (Manganese Violet)
- CI 77510 Prussian Blue (ferric ferrocyanide)
- CI 77163 White (Bismuth Oxychloride)
- CI 77288 Green (Dichromium Trioxide)
- CI 77000 White (Aluminum)
- CI 77289 Green (Chromium Hydroxide Green)
- CI 77400 Brown (Bronze)
- CI 77120 White (Barium Sulfate)
- CI 77820 White (Silver)
- CI 77002 White (Aluminum Hydroxide)
- CI 77947 White (Zinc Oxide)
- CI 77480 Yellow Brown (Gold)
- CI 77713 White (Magnesium Carbonate)
- CI 77489 Orange (Iron Oxide)
- CI 77019 (White Mica).

In preferred embodiments of the invention, the composition comprises at least one, preferably several, and preferably all, of the four mineral pigments CI77491, CI77492, CI77499 and CI77891. Preferably, these four pigments are the only pigments contained in the composition according to the invention.

The total pigment content in the composition is between 1 and 5%, preferably between 2 and 5%, more preferably between 2 and 4%, more preferably between 2 and 3%, and even more preferably approximately 2.5%, by weight relative to the total weight of the composition.

The amount of titanium dioxide pigment (or CI 77891) preferably represents at least 50%, preferably at least 75%, by weight of the total weight of the pigments contained in the composition.

Advantageously, the composition according to the invention has, at the end of its preparation process, a fixed shade, which does not change when applied to the skin.

It is also presented, as indicated above, in the form of a stable suspension of the particulate matter which goes into its constitution, including when the total content of pigment(s) is as high as 2% by weight, this content being able to even go up to 5% by weight, relative to the total weight of the composition.

By stable suspension, conventionally in itself, is meant the fact that the particles contained therein do not sediment or aggregate. Thus, in the composition according to the invention, virtually no settling of the insoluble particles contained therein is observed, including for long periods, in particular for a period as long as the general shelf life of the composition, which is more than 6 months, preferably more than 12 months, more preferably more than 18 months and preferentially 36 months. The stability and homogeneity of the composition can in particular be ensured by visual observation of the composition or a centrifugation test.

The composition according to the invention also has a good viscosity, without it even being necessary to use an additional ingredient having a thickening effect. In the present description, the term "good viscosity" means a viscosity allowing the composition to be distributed by different packaging, in particular tubes and pump bottles, and not to escape from the user's hands when it is distributed there. The cosmetic sun protection composition of the present invention is thus advantageously stable, with the desired viscosity, appearance, color, microscopy and pH range.

In particularly preferred embodiments of the invention, the cosmetic composition has a dynamic viscosity at 25°C +/- 2°C less than or equal to 10000 mPa.s, preferably between 700 and 10000 mPa.s, more preferably between 700 and 5000 mPa.s, and for example between 1500 and 4000 mPa.s. This viscosity can for example be measured using a Brookfield viscometer by applying the following parameters: spindle 5, speed 100 rpm, for 1 minute.

The composition according to the invention contains, as a suspending agent, one or more unmodified smectites. It preferably contains a single unmodified smectite.

Smectites are clays of the natural phyllosilicate class occurring mainly in the form of lamellar, foamy or spherical aggregates, characterized by a layered structure in which a central layer of octahedrally coordinated cations is sandwiched between two layers of [(Si,Al)O ₄ ] tetrahedra. Clay compounds/materials belonging to the smectite class are numerous. In this respect, in the class of dioctahedral smectites, we can notably mention beidellite and montmorillonite, and, in the class of trioctahedral smectites, hectorite, saponite, etc. Bentonite, essentially consisting of montmorillonite, is also considered according to the present invention as belonging to the smectite family.

As stated above, it has been discovered by the present inventors that, quite surprisingly, the presence, in a cosmetic composition in the form of an emulsion, of a smectite in a weight content of 0.3 to 2%, makes it possible to maintain particulate pigments in stable suspension therein up to a content of 5% by weight relative to the total weight of the composition, even when the composition contains the particulate sunscreen phenylene bis-diphenyltriazine, at a content of between 1 and 5% by weight, and, where appropriate, other particulate sunscreens insoluble in the vehicle of the composition. This advantageous result is advantageously not obtained to the detriment of the fluidity and sensory properties of the composition, nor to the detriment of its sun protection effectiveness. It also allows the stable formation of tinted sunscreen cosmetic compositions containing a sufficient quantity of pigments to cover a wide range of shades, adapting to all existing user skin tones.

This advantageous result is, equally surprisingly, not obtained when the smectite is modified, for example so as to increase its lipophilic character, by reaction with quaternary ammoniums, such as stearalkonium chloride or quaternium-18.

Preferably, the unmodified smectite(s) constitute(s) substantially the only suspending agents contained in the composition according to the invention.

Preferably, an unmodified smectite contained in the composition according to the invention as a suspending agent is hectorite or bentonite. For convenience, the terms “hectorite” and “bentonite”, when used alone in the present description (i.e., without mention of any group modifying the formula), specifically designate, respectively, unmodified hectorite and unmodified bentonite.

In preferred embodiments of the invention, the composition comprises, as a suspending agent, either only unmodified hectorite or only unmodified bentonite.

The total quantity of suspending agent(s) chosen from unmodified smectites in the composition according to the invention is preferably between 0.3 and 1.5% by weight, preferably between 0.3 and 1% by weight, relative to the total weight of the composition.

When the composition according to the invention contains hectorite as a suspending agent, the concentration of hectorite is preferably between 0.3 and 0.8% by weight, preferably between 0.3 and 0.5% by weight, relative to the total weight of the composition.

When the composition according to the invention contains bentonite as a suspending agent, the concentration of bentonite is preferably between 0.5 and 1.5% by weight, preferably between 0.8 and 1.2% by weight, relative to the total weight of the composition.

In particular embodiments of the invention, the mass ratio between the suspending agent(s) and the pigment(s) contained in the composition is between 0.08 and 0.6, preferably between 0.1 and 0.4.

The cosmetic composition according to the invention is preferably in the form of an oil-in-water type emulsion, that is to say that it comprises an oily phase kept dispersed homogeneously, in the form of fine droplets, in an aqueous phase, by the emulsifier(s) contained in the composition.

The cosmetic composition according to the invention comprises, by weight relative to the total weight of the composition, from 30 to 50% of water, preferably from 35 to 50% of water, or from 30 to 45% of water, more preferably from 35 to 45% of water, or from 40 to 50% of water, and even more preferably from 40 to 45% of water.

The composition according to the invention may contain a single oily emollient, or a plurality of oily emollients.

In the present description, the term oily emollient is understood to mean an ingredient present in the oily phase, and providing the composition according to the invention with good sensoriality, and a good capacity for softening the epidermis.

Preferably, the oily emollient(s) contained in the composition according to the invention are in liquid form, in particular at any temperature between 5°C and room temperature (between 20°C and 25°C).

Oily emollients typically comprise one or more polar chemical functions among the ester (-CO ₂ -), alcohol (-OH), ether (-O-), carbonate (-OCO ₂ -) and carboxylic acid (-CO ₂ H) functions, and one or more lipophilic groups, i.e. one or more aliphatic and/or aromatic hydrocarbon groups, in particular one or more saturated or unsaturated, linear or branched hydrocarbon chains, comprising between 6 and 20 carbon atoms, for example between 7 and 18 carbon atoms, in particular between 8 and 16 carbon atoms, a phenyl group (-C ₆ H ₅ ) and/or a phenylalkyl group.

The composition according to the invention preferably comprises at least one oily emollient chosen from C12-C15 alkyl benzoate, caprylic/capric triglycerides, dicaprylyl carbonate, coco-caprylate, coco-caprylate/caprate, diisopropyl sebacate, diethylhexyl succinate, isopropyl palmitate, isopropyl myristate, propylheptyl caprylate, phenethyl benzoate, dibutyl adipate, diisopropyl adipate, glyceryl tri-2-ethylhexanoate, pentaerythrityl tetra-2-ethylhexanoate, cetyl 2-ethylhexanoate, isononyl isonanoate, neopentyl glycol diheptanoate, diethylhexyl succinate, butylene glycol dicaprylate/dicaprate, octyldodecanol, propylene glycol dicaprylate/dicaprate and dicaprylyl ether, or any mixture thereof.

In particular embodiments of the invention, the oily emollient(s) contained in the composition according to the invention are liquid lipophilic emollients, capable of completely solubilizing the liposoluble sunscreen(s) possibly present in the composition, and are preferably chosen from C12-C15 alkyl benzoate, dicaprylyl carbonate, diisopropyl adipate, coco-caprylate caprate, diisopropyl sebacate, neopentyl glycol diheptanoate, diethylhexyl succinate, glyceryl tri-2-ethylhexanoate, isononyl isonanoate and cetyl 2-ethylhexanoate.

In particular embodiments of the invention, the oily emollient(s) are present in the composition in a total content of between 10 and 40% by weight, preferably between 15 and 40% by weight, more preferably between 15 and 35% by weight, or between 20 and 35% by weight, in particular between 20 and 30% by weight, for example between 20 and 25% by weight, relative to the total weight of the composition.

In particular embodiments of the invention, the C12-C15 alkyl benzoate represents between 30 and 100% by weight of the total weight of the oily emollients contained in the composition.

In particular embodiments of the invention, dicaprylyl carbonate represents between 30 and 100% by weight of the total weight of the oily emollients contained in the composition.

In particular embodiments of the invention, the diisopropyl adipate represents between 10 and 100%, preferably 10 and 50%, by weight of the total weight of the oily emollients contained in the composition.

In particular embodiments of the invention, the caprylic/capric triglycerides represent less than 5% by weight, preferably less than 1% by weight, of the total weight of the oily emollients contained in the composition.

The cosmetic composition according to the invention does not contain any humectant(s), or contains at most 5% by weight, for example between 0.01 and 5% by weight, preferably at most 4% by weight, for example between 0.01 and 4% by weight, in total of humectant(s), relative to the total weight of the composition.

For the purposes of this description, the term “humectant” means a polyol. A “polyol” (otherwise known as a polyalcohol) is defined here, in a conventional manner in itself, as a compound comprising a hydrocarbon chain with at least two carbon atoms and comprising at least two hydroxyl groups.

The polyol(s) that may be contained in the composition according to the invention may be natural or synthetic. They may have a linear, branched or cyclic molecular structure.

In the particular embodiments in which the composition according to the invention contains at least one humectant, the latter may be chosen from glycerin and its derivatives, and glycols and its derivatives. At least one humectant, preferably each of the humectants, contained in the composition according to the invention, is preferably chosen from the group consisting of glycerin, diglycerin, polyglycerin, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, pentylene glycol, hexylene glycol, 1,3-propanediol, 1,5-pentanediol, 1,2-hexanediol, octane 1,2-diol, polyethylene glycols, in particular having from 5 to 50 ethylene oxide groups, but also erythritol, threitol, arabitol, xylitol, ribitol, mannitol, sorbitol, galactitol, fucitol, iditol, inositol, volemitol, isomalt, maltitol, lactitol, maltotriitol, maltotetrol, and polyglycitol.

In particular embodiments of the invention, the composition thus contains at least one humectant, preferably at least glycerin, preferably in an amount less than or equal to 5% by weight relative to the total weight of the composition.

Preferably, the cosmetic composition according to the invention contains less than 3% by weight in total of humectant(s), relative to the total weight of the composition. Preferably, the cosmetic composition according to the invention contains in total less than 2% by weight of humectant(s), more preferably less than 1.5% by weight of humectant(s), and even more preferably less than 1% by weight of humectant(s), relative to the total weight of the composition.

The cosmetic composition according to the invention may comprise one or more emulsifiers, advantageously chosen from emulsifying agents capable of forming oil-in-water emulsions. The emulsifying agent(s) may, for example, be chosen from ethoxylated fatty alcohols, the products marketed under the names Montanov® 68 (Cetearyl Alcohol (and) Cetearyl Glucoside) and Montanov® 82 (Cetearyl Alcohol (and) Coco-Glucoside), potassium cetyl phosphate, glucoside waxes, glyceryl stearate citrate, lauryl glucoside and polyglyceryl-2 dipolyhydroxystearate, in particular the product marketed under the name Eumulgin® VL 75, lecithins, in particular hydrogenated soy lecithin, glycerol monostearate, sorbitan monostearate, sodium dilauramidoglutamide lysine, sodium stearoyl glutamate, in particular the product marketed under the name Eumulgin® SG, sodium stearoyl, sucrose stearate, etc.

In particular embodiments of the invention, the emulsifier(s) are present in the composition in a total content of 2 to 12% by weight, preferably 2 to 10% by weight, preferentially 2 to 8% by weight, more preferably 3 to 8% by weight, or even 2 to 6% by weight, in particular 2 to 5% by weight, for example 3 to 5% by weight, relative to the total weight of the composition. Such contents advantageously make it possible to obtain good stability of the emulsion and good sensoriality of the composition.

The composition according to the invention may further contain one or more cosmetically active agents for the care and/or hygiene of the skin, such as tocopheryl glucoside, zinc gluconate, extracts of Lens esculenta seeds.

The composition according to the invention may also comprise one or more cosmetically and/or dermatologically acceptable excipient(s).

As used herein, "cosmetically and/or dermatologically acceptable" is intended to mean that which is useful in the preparation, preservation or administration of a cosmetic or dermatological composition which is generally safe, non-toxic and neither biologically nor otherwise undesirable, and which is acceptable for human cosmetic or dermatological use.

The composition according to the invention may thus comprise excipients chosen in particular from consistency factors, texturizing agents, water-retentive agents, gelling agents, opacifiers, perfumes, essential oils, preservatives, sequestrants, bactericides, odor absorbers, alkalizing or acidifying agents, or any other ingredient usually used for the manufacture of sun compositions.

The composition according to the invention may thus in particular comprise one or more texturizing agents which may also be described as mattifying agents or oil-absorbing agents, preferably in the form of powder(s). Such texturizing agents may in particular be chosen from ingredients of the starch family, such as rice, corn and tapioca starches, talcs and cellulose and its derivatives, in particular microcrystalline cellulose.

In particular embodiments of the invention, the texturizing agent(s) represent(s) between 1 and 15% by weight, preferably between 1% and 10% by weight, more preferably between 2% and 6% by weight, relative to the total weight of the composition.

In particular embodiments of the invention, the composition does not comprise a texturizing agent chosen from nylon derivatives and polymethyl methacrylate (PMMA).

The composition according to the invention is preferably free of silica, silica being relatively controversial for application in the cosmetic field, in particular due to the negative environmental impact linked to its production.

The cosmetic composition according to the invention may further comprise one or more consistency factors.

This or these consistency factors are then preferably chosen from fatty alcohols, fatty acids, fatty acid esters, hydrogenated vegetable oils and other waxy bodies. Examples include glyceryl behenate or glyceryl laurate.

Preferably, the composition according to the invention contains only one consistency factor, or no consistency factor.

The total content of consistency factor(s) in the composition is preferably less than or equal to 5% by weight, for example less than or equal to 4% by weight, in particular less than or equal to 3% by weight, relative to the total weight of the composition.

The cosmetic composition according to the invention does not contain a gelling agent, or contains a maximum of 1% by weight in total of gelling agent(s), relative to the total weight of the composition. Thus, in particular embodiments of the invention, the composition is free of gelling agent, or it comprises from 0.01 to 1% by weight, preferably from 0.01 to 0.8% by weight, and preferentially from 0.01 to 0.5% by weight, of gelling agent(s), relative to the total weight of the composition.

At least one gelling agent, preferably each of the gelling agents, contained in the composition according to the invention, is preferably chosen from xanthan gum, scleroglucan gum, carrageenans, gellan gum, diutan gum, and Caesalpinia spinosa gum, or any of their mixtures.

The composition according to the invention may also comprise one or more water-retentive agents, in particular chosen from a copolymer of N-vinylpyrrolidone (VP) and eicosene (INCI name: VP/eicosen copolymer), a crosslinked polymer of trimethylpentanediol, adipic acid and glycerol (INCI name: trimethylpentanediol/adipic acid/glycerin crosspolymer), polyamide 3 (INCI), a copolymer of acrylate and octylacrylamide (INCI name: acrylates/octylacrylamide copolymer), and triacontanyl PVP (INCI).

In particular embodiments of the invention, the water-retentive agent(s) represent(s) in total between 0% and 2%, preferably between 0.01% and 1% by weight, relative to the total weight of the composition.

Preferably, the composition according to the invention comprises trimethylpentanediol/adipic acid/glycerin crosspolymer (INCI name) as a water-retentive agent.

In preferred embodiments of the invention, the composition is free of volatile silicones (also called volatile silicone oils).

Volatile silicones are short-chain cyclic polymers with the general formula [Si-(CH ₃ ) ₂ -O] _n with n=3-7. Generally referred to as cyclomethicone, regardless of the number of units, the most common are cyclotetrasiloxane (n=4) and cyclopentasiloxane (n=5), but cyclotrisiloxane (n=3), cyclohexasiloxane (n=6) and cycloheptasiloxane (n=7) can also be mentioned. Volatile silicones are substances known to be accumulative for the environment and non-biodegradable due to their high stability. Studies have shown that cyclopentasiloxane, for example, has a potential for bioaccumulation in aquatic environments (Gobas et al., 2015, Environmental Toxicology and Chemistry, 34, 12:2703–2714).

More generally, the composition according to the invention is preferably free of volatile ingredients. For the purposes of the present invention, the term “volatile ingredients” means non-alcoholic organic or inorganic compounds such as esters, silicones or alkanes, characterized by a flash point below 60°C.

By "flash point" (noted PE), we mean, in a classical way in itself, the minimum temperature at which a combustible substance emits vapors in sufficient concentration to form with the ambient air a gaseous mixture which ignites on contact with a flame or a hot point, but insufficient for combustion to propagate by itself in the absence of the so-called pilot flame. According to Regulation (EC) No 1272/2008 on the classification, labeling and packaging of substances and mixtures, a substance with a PE such as 23°C ≤ PE < 60°C belongs to category 3 "low flammability".

Thus, the composition according to the present invention is in particular preferably free of volatile esters, such as isohexyl neopentanoate, and/or volatile alkanes, such as isohexadecane.

The composition according to the invention may contain one or more monoalcohols. However, it is preferably free of monoalcohols.

In particular embodiments of the invention, the composition is furthermore free of essential oils. Indeed, most essential oils contain allergens, a source of irritation and skin intolerance. Dyes with the same characteristics are preferably also avoided for similar reasons.

In particular embodiments of the invention, the composition is free of ethylenediaminetetraacetic acid (EDTA). Alternatively, it may contain such an acid.

In particular embodiments of the invention, the tinted cosmetic composition is free of microplastics.

The term "microplastic" within the meaning of the present invention designates microparticles of synthetic polymers, and refers to the definition given in the draft amendment to Annex XVII of REACH Regulation (EC) No. 1907/2006, D083921/01 of September 5, 2022 ("COMMISSION REGULATION (EU) …/… of XXX amending Annex XVII to Regulation (EC) No 1907/2006 of the European Parliament and of the Council concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) as regards synthetic polymer microparticles" accessible in particular at the url address: https://ec.europa.eu/transparency/comitology-register/screen/documents/083921/1/consult?lang=en). According to this document, microplastics, or synthetic polymer microparticles, are defined as polymers that are solid and either are contained in particles and constitute at least 1% by weight of those particles, or form a continuous surface coating on particles, where at least 1% by weight of those particles meet one of the following conditions: (a) all particle dimensions are less than or equal to 5 mm; (b) the length of the particles is less than or equal to 15 mm and their length to diameter ratio is greater than 3. The following polymers are excluded from this designation:
(a) polymers resulting from a polymerization process that has occurred in nature, which are not chemically modified substances;
(b) polymers which are degradable as proven in accordance with Annex [X] of the document;
(c) polymers which have a solubility greater than 2 g/L as proven in accordance with Annex [Y] of the document (solubility test in water at pH 7 with stirring for 24 h at 20°C, with a polymer loading of 10 g/1000 mL, according to the protocol of Test No. 120 or Test No. 105 of the OECD Guidelines for the Testing of Chemicals);
(d) polymers that do not contain carbon atoms in their chemical structure.
Microparticles of synthetic polymers covered by the derogation provided for in point 4a of the said draft amendment to Annex XVII are also excluded from this definition.

More generally, microplastics can be defined as particles with all dimensions less than 5 mm, formed or coated with synthetic solid organic polymer(s) that are insoluble in water and non-biodegradable.

Thus, in particular, the cosmetic composition according to the invention is preferably free of microplastic polyquaterniums, ingredients used in many cosmetic compositions proposed by the prior art.

It is also preferably free of microplastic acrylates.

On the other hand, in particular embodiments of the invention, the cosmetic composition may comprise one or more non-microplastic acrylates, in particular chosen from the group consisting of (INCI names):
- Acrylates/C10-30 Alkyl Acrylate Crosspolymer,
- Acrylates/vinyl isodecanoate crosspolymer,
- Sodium Polyacrylate,
- Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer,
- Acrylates Copolymer,
- Polyacrylate-13,
- Acrylates/t-Butylacrylamide Copolymer,
- Octylacrylamide/acrylates/butylaminoethyl methacrylate copolymer,
- Polyacrylamide,
- VP/Methacrylamide/Vinyl Imidazole Copolymer,
used alone or in any of their mixtures.

The composition according to the invention may be presented in any conventional form in itself, this form being suitable for topical application to the skin and/or hair. It may in particular, but not limited to, be presented in the form of a fluid emulsion, a rich emulsion, a cream, a milk, a lotion.

Throughout this description, the term skin includes both the skin itself and the mucous membranes, in particular the lips. The term cutaneous includes both that which relates to the skin and that which relates to the mucous membranes.

The composition according to the invention may be intended to be applied to the skin of the face and/or body, and/or to the hair. It may, for example, be in the form of a protective, treatment or care cream or balm for the face, hands and/or body, or a protective, treatment or care body lotion.

Another aspect of the invention further relates to a process for preparing a composition according to the invention, as described above, in particular in the form of an oil-in-water emulsion. This process comprises the following steps:
- preparation of the oily phase: prior solubilization and where appropriate, of liposoluble filter(s) in the oily emollient(s) at a temperature between 70°C and 85°C, typically at 80°C, with stirring, preferably with mechanical stirring; then addition of the other constituent ingredients of the oily phase of the emulsion – such as the pigment(s) – to the mixture obtained previously, at a temperature between 70°C and 85°C, typically at 80°C, with stirring, preferably with mechanical stirring;
- preparation of the aqueous phase: prior dispersion of the phenylene bis-diphenyltriazine and, where appropriate, of the other particulate organic filter(s) in water, at a temperature between 50°C and 75°C, typically at 60°C, with stirring, preferably with mechanical stirring; then addition of the other constituent ingredients of the aqueous phase of the emulsion to the mixture obtained previously, at a temperature between 50°C and 75°C, typically at 60°C, with stirring, preferably with mechanical stirring;
- addition of a suspending agent chosen from unmodified smectites in at least one of said aqueous phase and said oily phase, and preferably in said aqueous phase;
- addition of emulsifier(s) in at least one of said aqueous phase and said oily phase;
- introduction of the previously obtained oily phase into the previously obtained aqueous phase, with stirring, preferably with mechanical stirring, until a homogeneous solution is obtained;
- cooling the emulsion thus obtained to room temperature; and
- optionally, addition of perfume, active agent(s) and/or texturizing agent(s) in powder form, with stirring, preferably with mechanical stirring.

The cosmetic composition according to the invention is in particular intended to be applied topically to any area of skin of a subject likely to be exposed to solar radiation or artificial ultraviolet radiation, in particular an area of skin on the face or body of the subject.

Another aspect of the invention relates to the use of a composition according to the invention for sun protection of the skin and/or hair of a subject, this use comprising the topical application of the composition to said skin and/or said hair. The subject may be a mammal, in particular a human.

The composition according to the invention can, for example, be applied topically to an area of skin of the subject concerned, such as the skin of the face, including the lips, or of the body, in an effective amount, as often as necessary before or during exposure to solar radiation.

The invention is also expressed in terms of a therapeutic method for the sun protection of an area of skin of a subject, in particular a human, this method comprising the topical application, to this area of skin, of an effective amount of a composition according to the invention.

This method may meet one or more of the characteristics described above with reference to the use of the composition according to the invention for sun protection of the skin and/or hair.

The present invention also relates to a method for non-therapeutic cosmetic treatment of an area of skin and/or hair of a subject, in particular a human, for sun protection of this area of skin and/or hair, by topical application, to this area of skin and/or hair, of an effective amount of a composition according to the invention.

Here again, this method can meet one or more of the characteristics described above with reference to the use of the composition according to the invention for sun protection of the skin and/or hair.

Another subject of the invention relates to the non-therapeutic cosmetic use of a composition according to the invention for the sun protection of an area of skin and/or hair of a subject, in particular a human. This use comprises the topical application of this composition to this area of skin and/or this hair. It may meet one or more of the characteristics described above with reference to the use of the composition according to the invention for the sun protection of the skin and/or hair.

The characteristics and advantages of the invention will appear more clearly in light of the examples of implementation below, provided for purely illustrative purposes and in no way limiting the invention, with the support of the FIG. 1 , in which:

FIG. 1 There FIG. 1 represents a graph showing the share of the total surface area (average in pixels) occupied by heterogeneous zones on a skin area of interest of a subject, determined by a skin analysis system by imaging coupled with an image analysis module by color tracking, respectively at an initial time (T0), then 10 to 30 minutes after application to the skin area of interest of a cosmetic composition in accordance with the invention (Timm).

1/ Example 1 – General formula of the tested compositions

The tested compositions, in the form of an oil-in-water emulsion, comprising phenylene bis-diphenyltriazine, correspond to the general formula presented in Table 1 below.

Ingredients Quantity (% w/w) Water 30 - 50 Phenylene bis-diphenyltriazine in the form of aqueous dispersion: Phenylene bis-diphenyltriazine 3.5 PPG-1 PPG-9 Lauryl Glycol Ether 0.3 Additional UV filters:
Bis-ethylhexyloxyphenol methoxyphenyl Triazine
Ethylhexyl Triazone
Diethylamino Hydroxybenzoyl Hexyl Benzoate 8 - 15 Oily emollients:
C12-C15 alkyl benzoate
Dicaprylyl carbonate
Diisopropyl adipate
C9-C12 alkane & Coco-caprylate caprate 20 - 25 Emulsifiers:
Potassium cetyl phosphate
Lauryl Glucoside
Polyglyceryl-2 dipolyhydroxystearate 2 - 8 Active agents: Tocopheryl glucoside 0.2 Zinc gluconate 0.1 Excipients: Trimethylpentanediol/Adipic Acid/Glycerin Crosspolymer 1 Starches 2 – 6 Conservative qs Suspensive agent X Pigment(s):
CI77491
CI77492
CI77499
CI77891 Y

Table 1 – General formula of the tested compositions

2/ Example 2 - Objectification of the technical problem

Two compositions not in accordance with the invention are tested to assess their stability by focusing on the visual appearance, a centrifugation test and a stability study. Viscosities are also measured. Finally, a microscopy analysis of the formulas is carried out.

The different protocols of the tests carried out are as follows.

Fluidity
Viscosity measures the fluid resistance. This analysis helps understand how fluid or viscous the formula is, and how this property behaves throughout the stability study. Product viscosity impacts packaging selection, active ingredient release, spreadability, and the consumer experience. This analysis is performed at 25°C, using a Brookfield viscometer, with the following parameters: spindle 5, 100 rpm, for 1 minute.
Brookfield viscometers use the principle of rotational viscosity - the torque required to rotate an object, such as a spindle, in a fluid indicates the fluid's viscosity. The torque is applied via a calibrated spring to a disc or shaft immersed in the fluid under test, and the spring's deflection measures the viscous drag of the fluid against the shaft.

Emulsion stability by centrifugation
The centrifugation test is performed on a fresh sample of the compositions. This sample is subjected to high-speed rotation for a certain time, in this case 4000 rpm for 20 minutes. The objective is to stress the formula and anticipate potential instabilities without having to wait too long for the stability study to complete. The dispersed phase of an oil-in-water emulsion tends to separate and rise to the top of the emulsion, forming a layer of oil droplets. This phenomenon is called creaming. It is one of the first signs of emulsion instability.

Homogeneity
The visual aspect allows us to appreciate the homogeneity of the composition. This test is carried out by the same person, trained in this type of exercise.
A microscopic evaluation of the microstructure of the composition is carried out to check for the presence or absence of signs of future instabilities. In general, a good emulsion profile is sought, i.e. fine, rounded oil droplets of the same size, homogeneously dispersed in the continuous phase, a cohesive edge, and therefore no signs of large undispersed particles should be present.

The tested compositions correspond to the general formula in Table 1, in which X is equal to 0 (absence of smectite). The values of Y are as follows:
- composition A: Y = 1.2
- composition B: Y = 2.5.

The results obtained are shown in Table 2.

Composition HAS B Viscosity (mPa.s) 2100 1809 Centrifugal stability OK KO Homogeneity: Visual aspect Compliant Non-compliant Microscopy OK Agglomerates

Table 2 – Evaluation of the stability of compositions not in accordance with the invention – OK means “satisfactory”, KO means “not satisfactory”

Composition A corresponds to a tinted sunscreen composition based on phenylene bis-diphenyltriazine, whose pigment mixture concentration is relatively low, namely 1.2% by weight relative to the total weight of the composition. As shown in Table 2, all tests are positive with this composition A. It is stable, fluid and homogeneous.

Composition B is very close to composition A, only the concentration of the same mixture of pigments is different, namely 2.5% by weight compared to the total weight of the composition. This higher concentration of pigments changes everything, since a non-homogeneous appearance is observed, the pigments and the particles of the filter then form agglomerates when the composition is observed under a microscope.

Thus, when the pigment concentration increases, and is greater than 1.2% by weight, the stability of the composition without smectite is no longer assured.

3/ Example 3 – Evaluation of different compositions

Two compositions in accordance with the invention C1 and C2, as well as two comparative compositions not in accordance with the invention D and E, all corresponding to the general formula of Table 1, are tested in this example. Comparative compositions D and E contain, respectively, as suspending agent, a modified smectite or magnesium aluminum silicate (Mg Al Silicate).

The stability of these compositions is evaluated according to the protocols described in example 2.

The results obtained, for each composition, are indicated in Table 3.

Composition C1 C2 D E Y 2.5 2.5 2.5 2.5 Suspensive agent Hectorite Bentonite Stearalkonium hectorite Mg Al Silicate X 0.3 1 0.3 0.3 Viscosity (mPa.s) 2752 2886 2786 3490 Centrifugal stability OK OK KO KO Homogeneity: Visual aspect Compliant Compliant Non-compliant Non-compliant Microscopy OK OK Agglomerates Agglomerates

Table 3 - Evaluation of the stability of compositions in accordance with the invention C1 and C2 and of compositions not in accordance with the invention D and E – OK means “satisfactory”, KO means “not satisfactory”

It is observed that when the composition contains 0.3% by weight of hectorite (composition C1) or 1% by weight of bentonite (composition C2), even with 2.5% by weight of the pigment mixture, the various stability criteria evaluated are in line with expectations. The compositions appear stable and are homogeneous under microscopic examination.

On the other hand, in the presence of other suspending agents such as stearalkonium hectorite (provided by the product Bentone Gel® TN V), which is a modified smectite (composition D), the stability of this formula is altered, and agglomerates form.

Similarly, in the presence of another suspending agent other than smectites, aluminium and magnesium silicate, a lack of homogeneity and stability was observed even though the viscosity was within the expected range.

This demonstrates that the choice of the suspending agent is essential, and only unmodified smectites are judicious and allow the tested compositions to be stabilized.

4/ Example 4 – Other comparative examples

Two comparative compositions not in accordance with the invention F and G, corresponding to the general formula of table 1, and containing, respectively, a content of suspending agent chosen from unmodified smectites greater than that recommended by the invention, or a content of pigments greater than that recommended by the invention,

The stability of these compositions is evaluated according to the protocols described in example 2.

The results obtained, for each composition, are indicated in Table 4.

Composition F G Y 2.5 8 Suspensive agent Hectorite Hectorite X 2.5 0.5 Viscosity (mPa.s) > 10,000 1470 Centrifugal stability BORN KO Homogeneity: Visual aspect BORN Non-compliant Microscopy BORN Agglomerates

Table 4 - Evaluation of the stability of compositions not in accordance with the invention – OK means “satisfactory”, KO means “not satisfactory” and NE means “ not evaluated”

It is interesting to note that too much suspending agent (2.5% by weight in composition F) is harmful, since a much too high viscosity (> 10,000 mPa.s) is then measured. Such viscosity is not possible, because it affects the texture and sensoriality of the formulas.

Similarly, it is observed that with too high a quantity of pigments (8% by weight), even with hectorite as a suspending agent, at a concentration of 0.5% by weight (composition G), the different particles are not dispersed homogeneously. The particulate loads are probably too high and the suspension is not stable, even forming agglomerates.

The inventors thus demonstrate that, in the context of a tinted sunscreen composition based on phenylene bis-diphenyltriazine and comprising at least 2% by weight of a mixture of pigments, only unmodified smectite in an adequate quantity (i.e. between 0.3 and 2% by weight) is capable of suspending this composition in a homogeneous and stable manner, without altering the desired fluidity.

5/ Example 5 - Analysis of the coverage of a composition according to the invention

This analysis is carried out using the VISIA®-CR device from Canfield (skin imaging analysis system).

The tested composition, named C3, is described in Table 5.

Ingredients Quantity (% w/w) Water 30 - 50 Phenylene bis-diphenyltriazine in the form of aqueous dispersion: Phenylene bis-diphenyltriazine 3.5 PPG-1 PPG-9 Lauryl Glycol Ether 0.3 Additional UV filters:
Bis-ethylhexyloxyphenol methoxyphenyl Triazine
Ethylhexyl Triazone
Diethylamino Hydroxybenzoyl Hexyl Benzoate 8 - 15 Oily emollients:
C12-C15 alkyl benzoate
Dicaprylyl carbonate
Diisopropyl adipate
C9-C12 alkane & Coco-caprylate caprate 20 - 25 Emulsifiers:
Potassium cetyl phosphate
Lauryl Glucoside
Polyglyceryl-2 dipolyhydroxystearate 2 - 8 Active agents: Tocopheryl glucoside 0.2 Zinc gluconate 0.1 Lens Esculenta Seed Extract (p-Refinyl®) 1 Excipients: Trimethylpentanediol/Adipic Acid/Glycerin Crosspolymer 1 Rice starch and tapioca starch 2 – 6 Conservative qs Hectorite 0.3 Pigment(s):
CI77491
CI77492
CI77499
CI77891 2.5

Table 5 – Composition C3 in accordance with the invention

Images of an area of skin on the forehead of the test subjects are acquired using the VISIA®-CR device, by a technician trained and experienced in this analysis, at the following times:
- T0: before applying the composition to the affected area of skin,
- Timm: between 10 and 30 minutes after this application.

The selected skin area, called the area of interest, is an area of heterogeneous pigmentation (with the presence of spots).

An evaluation of the images captured by the device is carried out in order to study the coverage of this C3 composition, using the FrameScan® software. This software consists of two analysis modules, one colorimetric, used for the analysis of color and brightness, and the other morphological, used for the analysis of the morphology of spots, the density of wrinkles and the homogeneity of the skin.

To assess the potential coverage of the C3 composition according to the invention, the images obtained at T0 are compared with the images obtained immediately after application of the composition (Timm). For the coverage analysis, photos with a cross-polarized filter are used as well as a color tracking module of the FrameScan® software, in which the total surface parameter is used.

The software calculates the share of the total area of the area of interest occupied by heterogeneous areas at T0 and Timm. The results are shown on the FIG. 1 .

It is observed that a statistically significant reduction (of 65%) of the parameter which is the proportion of the total surface occupied by heterogeneous zones, is obtained after application of the composition according to the invention to the skin zone concerned, reflecting a much more uniform appearance of the skin and therefore fewer heterogeneous zones.

The inventors therefore clearly demonstrate that a composition according to the invention is capable of making the appearance of the skin more uniform.

Claims (17)

Tinted cosmetic sunscreen composition in the form of an emulsion, suitable for topical application to the skin, comprising, the percentages being expressed by weight relative to the total weight of the composition:
- 30 to 50% water,
- 1 to 5% of the particulate sunscreen phenylene bis-diphenyltriazine,
- at least one emulsifier,
- at least one oily emollient,
- at least one pigment,
characterized in that the total content of pigment(s) in the composition is between 1 and 5% by weight relative to the total weight of the composition, and in that said composition further comprises a suspending agent chosen from unmodified smectites, the quantity of suspending agent(s) chosen from unmodified smectites in the composition being between 0.3 and 2% by weight relative to the total weight of the composition. Cosmetic composition according to claim 1, wherein said at least one pigment is chosen from iron oxides and titanium dioxide, and any of their mixtures. Cosmetic composition according to claim 2, comprising the four pigments CI 77491, CI 77492, CI 77499 and CI 77891. Cosmetic composition according to any one of claims 1 to 3, in which said suspending agent chosen from unmodified smectites is hectorite or bentonite. Cosmetic composition according to any one of claims 1 to 4, in which the total content of emulsifier(s) is between 2 and 12% by weight relative to the total weight of the composition. Cosmetic composition according to any one of claims 1 to 5, in which the total content of oily emollient(s) is between 10 and 40% by weight relative to the total weight of the composition. Cosmetic composition according to any one of claims 1 to 6, wherein said at least one oily emollient is selected from C12-C15 alkyl benzoate, caprylic/capric triglycerides, dicaprylyl carbonate, coco-caprylate, coco-caprylate/caprate, diisopropyl sebacate, diethylhexyl succinate, isopropyl palmitate, isopropyl myristate, propylheptyl caprylate, phenethyl benzoate, dibutyl adipate, diisopropyl adipate, glyceryl tri-2-ethylhexanoate, pentaerythrityl tetra-2-ethylhexanoate, cetyl 2-ethylhexanoate, isononyl isonanoate, neopentyl glycol diheptanoate, diethylhexyl succinate, butylene glycol dicaprylate/dicaprate, octyldodecanol, propylene glycol dicaprylate/dicaprate and dicaprylyl ether, and any mixture thereof. Cosmetic composition according to any one of claims 1 to 7, comprising at least one additional sunscreen, preferably at least one liposoluble organic sunscreen chosen from diethylamino hydroxybenzoyl hexyl benzoate, bis-ethylhexyloxyphenol methoxyphenyl triazine, diethylhexyl butamido triazone, ethylhexyl triazone, butyl methoxydibenzoylmethane, or any of their mixtures. Cosmetic composition according to claim 8, comprising the additional sun filters:
- diethylamino hydroxybenzoyl hexyl benzoate,
- bis-ethylhexyloxyphenol methoxyphenyl triazine and,
- ethylhexyl triazone or diethylhexyl butamido triazone. Cosmetic composition according to any one of claims 1 to 9, not comprising ethylhexyl salicylate, octocrylene, ethylhexyl methoxycinnamate, isoamyl methoxycinnamate, homosalate, para-aminobenzoic acid (PABA), octyl dimethyl PABA, 3-methylbenzylidene-camphor, 4-methylbenzylidene-camphor, benzophenone-3 and/or benzophenone-4. Cosmetic composition according to any one of claims 1 to 10, further comprising between 1 and 15% by weight of texturizing agent(s), relative to the total weight of the composition. Cosmetic composition according to any one of claims 1 to 11, further comprising an extract of Lens esculenta seeds. Cosmetic composition according to any one of claims 1 to 12, further comprising at least one humectant, preferably at least glycerin, preferably in an amount less than or equal to 5% by weight relative to the total weight of the composition. Cosmetic composition according to any one of claims 1 to 13, free from gelling agent or comprising from 0.01 to 1% by weight of gelling agent(s) relative to the total weight of the composition. Cosmetic composition according to any one of claims 1 to 14, in the form of an oil-in-water emulsion. Cosmetic composition according to any one of claims 1 to 15, having a dynamic viscosity at 25°C of between 700 and 10000 mPa.s. Cosmetic composition according to any one of claims 1 to 16, for its use for sun protection of the skin and/or hair of a subject, according to which said composition is applied to said skin and/or said hair topically.