FR2736545A1 - Use of hollow particles of copolymer of vinylidene chloride, acrylonitrile and methyl (meth)acrylate - Google Patents

Abstract

Deformable, hollow particles of an expanded copolymer of vinylidene chloride, acrylonitrile and methyl (meth)acrylate, with size 1-250 mu m are used in cosmetic and/or dermatological compsns. contg. TiO2 pigment.

Description

USE OF DEFORMABLE HOLLOW PARTICLES AGAINST THE
WHITENING OF A COSMETIC COMPOSITION AND / OR
DERMATOLOGICAL CONTAINING PIGMENTS OF TITANIUM OXIDE
The invention relates to the use of particular deformable hollow particles in a cosmetic and / or dermatological composition containing titanium oxide pigments, in order to reduce or eliminate the bleaching usually observed during the application to the skin of this type of composition, these hollow particles having a particle size ranging from 1 μm to 250 μm, and consisting of copolymer of vinylidene chloride, (meth) acrylate and acrylonitrile.

The compositions according to the invention can in particular be used for the photoprotection of the skin and the hair in the form of sunscreen compositions, but also for the make-up, the care, the hygiene of the skin, of the face, of the human body. including the scalp and mucous membranes, hair and finally for the therapeutic treatment of the skin and mucous membranes.

Thus, the composition to which the invention applies may be an oil-in-water emulsion, a water-in-oil emulsion, a care cream, a balm, a blush or a fluid or cast foundation, a dermopharmaceutical ointment.

It is known that light radiation of wavelengths between 280 nm and 400 nm allows the browning of the human epidermis and that the wavelength rays between 280 nm and 320 nm, known under the name of UV -B, cause erythema and skin burns that can affect the development of natural tanning; this UV-B radiation must therefore be filtered.

It is also known that UV-A rays of wavelengths between 320 nm and 400 nm, which cause browning of the skin, are capable of inducing an alteration thereof, particularly in the case of sensitive skin or skin continuously exposed to solar radiation. UV rays
In particular, they cause a loss of elasticity of the skin and the appearance of wrinkles leading to premature aging. They promote the triggering of the erythematous reaction or amplify this reaction in some subjects and may even be the cause of phototoxic or photoallergic reactions. It is therefore desirable to also filter the UV-A radiation.

To filter UV-A and UV-B radiation, there are different types of sunscreens on the market: mineral pigments and organic filters. These filters must be able to absorb or block the harmful rays of the sun while remaining harmless for the user.

Thus, many organic solar filters capable of absorbing more or less selectively harmful UV rays have been proposed to date in the field of cosmetics. For various reasons, however, these filters are not entirely satisfactory.

This is why we seek more and more to avoid the use of these organic filters by emphasizing the use of mineral pigments, which also play the role of solar filters, mainly by diffusion I reflection of
UV, while providing greater security for the user.

As such, the most common mineral pigment used to date is titanium oxide whose filtering properties are well known.

However, in order to obtain suitable protective factors, it is necessary to be able to introduce high percentages into the solar compositions.
TiO2, in particular greater than 5% by weight.

But at such levels of TiO2, one observes the appearance of a bleaching when applying these compositions on the skin. This phenomenon is not desirable from an aesthetic point of view.

The present invention aims to solve the problem stated above.

Thus, following important research conducted in the field of photoprotection mentioned above, the Applicant has now discovered, totally unexpectedly and surprisingly, that the introduction of deformable hollow particles of specific gravity and particle size in a composition containing TiO 2 pigments significantly reduced the bleaching phenomenon intrinsically attached thereto.

This discovery is the basis of the present invention.

In addition to reducing the bleaching phenomenon, these particles also impart softness and homogeneity to the application as well as greater ease of spreading.

More specifically, the invention therefore relates to the use of deformable hollow particles, in a cosmetic and / or dermatological composition containing TiO 2 pigments, for reducing or eliminating bleaching when applying this composition to the skin, these hollow particles having a particle size ranging from 1 μm to 250 μm and being formed of a copolymer of vinylidene chloride, acrylonitrile and methyl (meth) acrylate.

The invention also relates to a method for reducing or eliminating bleaching during the application of a cosmetic and / or dermatological composition containing titanium oxide pigments, comprising introducing deformable hollow particles having a particle size ranging from from 1 μm to 250 μm and being formed from a copolymer of vinylidene chloride, acrylonitrile and methyl (meth) acrylate.

By "deformable", it should be understood that the particles are flexible and elastic after crushing, they resume their original shape.

The particles generally have a particle size ranging from 1 μm to 250 μm.

Advantageously, the particles have a particle size of less than 100 μm.

Indeed, the finer the particles, the softer the composition on application. Preferably, the particles have a particle size ranging from 10 μm to 60 μm.

Advantageously, the particles have a density ranging from 15 kg / m 3 to 200 kg / m 3 and better still greater than 40 kg / m 3 and / or less than 100 kg / m 3 and especially ranging from 60 kg / m 3 to 80 kg / m 3.

For example, a copolymer containing from 1% to 60% of units derived from vinylidene chloride, from 20% to 90% of units derived from acrylonitrile and from 1% to 50% of units derived from acrylic monomer, the sum of the percentages (by weight) being equal to 100. The acrylic monomer is, for example, a methyl acrylate or methacrylate and, in particular, methacrylate. These particles are in particular in the dry state or hydrated.

This copolymer is nontoxic and non-irritating to the skin.

Preferably, the particles are in the form of microspheres.

The particles of the invention can be obtained, for example, according to the processes of patents and patent applications EP-56 219, EP-348 372, EP486 080,
EP-320,473, EP-112,807 and US-3,615,972.

The internal cavity of the particles in principle contains a gas which may be air, nitrogen or a hydrocarbon such as isobutane or isopentane.

The hollow particles that can be used in the invention are in particular those sold under the trademark Expancel by the Nobel Casco Company, such as Expancel 551 DE 20 having a particle size of 30 μm and a density of about 65 kg / m3; Expancel 551 DE 50 with a particle size of 40 μm.

In the compositions of the invention, use is preferably made of 0.1% to 10% by weight of particles and better still of 0.3% to 5% by weight and still of 0.3% to 2%, relative to total weight of the composition.

One of the essential characteristics of the compositions contemplated by the present invention is to contain titanium oxide pigments. The pigments contemplated by the present invention are the known titanium oxide pigments, usually used in cosmetics as fillers or as filters, which can be treated or untreated. Such pigments include titanium oxide nanopigments. By nanopigments is meant pigments whose average size of the elementary particles is between 5 and 100 nm.

The titanium oxide may be in rutile, anatase or amorphous form, but preferably in rutile and / or anatase form.

The treated pigments may for example be treated with alumina, silica, aluminum compounds, silicon compounds, sodium compounds, iron oxides, iron esters, stearic acid, glycerol .

More particularly, the treated pigments may be titanium oxides treated with: silica and alumina such as MICROTITANIUM DIOXIDE MT 500 products
SA and MICROTITANIUM DIOXIDE MT 100 SA from the company TAYCA, and the products TIOVEIL Fin, TIOVEIL OP, TIOVEIL MOTG and TIOVEIL
IPM from the company TIOXIDE, alumina and aluminum stearate such as the product MICROTITANIUM
DIOXIDE MT 100 T from the company TAYCA, - aluminum alumina and laurate such as the MICROTITANIUM product
DIOXIDE MT 100 S from TAYCA, - iron oxides and iron stearate such as MICROTITANIUM
DIOXIDE MT 100 F from TAYCA - silica, alumina and silicone such as MICROTITANIUM products
DIOXIDE MT 100 SAS, MICROTITANIUM DIOXIDE MT 600 SAS and MICROTITANIUM DIOXIDE MT 500 SAS from the company TAYCA, sodium hexametaphosphate such as the product MICROTITANIUM
DIOXIDE MT 150 W from the company TAYCA, octyltrimethoxysilane such as the product T-805 from the company Degussa, - alumina and stearic acid such as the product UVT-M160 company
KEMIRA, alumina and glycerine such as the UVT-M212 product from the company KEMIRA, alumina and silicone such as the product UVT-M262 from the company KEMIRA.

The untreated titanium oxides may, for example, be those sold by Tayca under the trade names MICROTITANIUM
DIOXIDE MT 500 B or MICROTITANIUM DIOXIDE MT 600 B.

The titanium oxide (nano) pigment (s) may be present in the composition according to the invention in a proportion of between 1 and 30% by weight relative to the total weight of the composition, preferably between 2 and 25% by weight. by weight relative to the total weight of the composition.

Thanks to the invention, it is possible without any problem to introduce relatively high amounts of TiO 2, in particular greater than 5% by weight, or even greater than 10% by weight, or even greater than 15% by weight, and this without being penalized. by the problem of money laundering mentioned above.

The other constituents that can be included in the formulation of the compositions targeted by the invention, in particular oils, waxy compounds, thickeners, emulsifiers and gelling agents, are those conventionally used in the cosmetic and / or dermatological field.

By oil is meant a liquid compound at room temperature. By wax is meant a solid or substantially solid compound at room temperature, and whose melting point is generally greater than 35 ° C.

As oils, mention may be made of mineral oils (petroleum jelly); vegetable (sweet almond oil, macadamia, blackcurrant seed); synthetic such as perhydrosqualene, alcohols, fatty acids or esters (octyl palmitate, isopropyl lanolate, triglycerides including those of capriquelcaprylic acids), oxyethylenated or oxypropylenated esters and fatty ethers; silicone (cyclomethicone, polydimethylsiloxane or PDMS) or fluorinated, polyalkylenes.

As waxy compounds, mention may be made of jojoba oil, paraffin, carnauba wax, beeswax, and hydrogenated castor oil.

As emulsifiers, it is possible to use fatty acid esters of polyethylene glycol (PEG), esters of fatty acids and of glycerol (glyceryl stearate) or esters of fatty acids and of sugar (sorbitan stearate), as well as their polyoxyethylenated or polyoxypropylenated derivatives, cyclomethicones and dimethicone copolyols, anionic surfactants (alkylphosphate of K or
Na), the polyalkoxylated fatty alcohols.

Preferably, the polyalkoxylated fatty alcohols are used, such as oxypropylenated butyl alcohols, oxyethylenated caprylic alcohols and oxyethylenated cetyl alcohols.

As thickeners, it is possible to use crosslinked polyacrylic acids, guar gums and modified or unmodified celluloses such as hydroxypropyl guar gum, methylhydroxyethylcellulose, hydroxypropylmethylcellulose or hydroxyethylcellulose.

As gelling agents, mention may be made of modified clays (bentones), metal salts of fatty acids (aluminum stearate), ethylenelacrylate copolymers, silicas, polyethylenes, calcium silicates or else ethylcellulose.

The compositions targeted by the present invention may also contain various ingredients conventionally used in the cosmetic, dermatological or dermopharmaceutical field, such as dyestuffs and pigments other than titanium oxides, solvents (water, alcohols, etc.) and preservatives. perfumes, moisturizing active agents, ultraviolet absorbing agents (sunscreens, inorganic pigments other than titanium oxides), pulverulent agents other than deformable hollow particles, bactericidal agents and / or odor absorbers.

These compositions may, in addition, contain one or more hydrophilic and better lipophilic cosmetic or dermatological active agents, in particular with a view to treating and / or preventing cutaneous affections such as acne, mycoses, eczema, rosacea, seborrheic dermatitis, helio dermatoses, skin aging and scalp conditions. These compositions are intended for the treatment of the skin by the topical route.

The compositions concerned by the invention may be prepared according to the techniques well known to those skilled in the art, in particular those intended for the preparation of oil-in-water or water-in-oil type emulsions.

This composition may be in particular in the form of an emulsion, simple or complex (O / W, W / O, O / W / H or W / O / W) such as cream, milk, gel or gel cream, powder, solid stick and optionally be packaged in aerosol and be in the form of foam or spray.

The invention is particularly suitable for the case of anhydrous compositions, especially anhydrous creams.

Concrete but non-limiting examples illustrating the invention will now be given.

EXAMPLE 1
Comparative tests were carried out to demonstrate the improvement in bleaching by the use of deformable hollow microspheres of an expanded copolymer of vinylidene chloride and acrylonitrile or vinylidene chloride, acrylonitrile and of methacrylate, in a composition containing titanium oxide pigments.

For this purpose, an anhydrous composition containing a certain percentage x of Expancel and 20% of titanium oxide was prepared in an anhydrous support composed of a polyalkoxylated fatty alcohol (oxypropylenated butyl alcohol), a fatty substance of the class of esters (isopropyl palmitate), a wax having a melting point of 60 to 80 ° C (hydrogenated castor oil), a thickening fatty substance (glycerol monostearate) and an oil (hydrogenated polydecene).

Five different compositions A, B, C, D and E were thus made by varying the content x from 0 to 2%.

For the evaluation of the bleaching, tests were carried out on five models.

The whitening intensity (lb) is measured according to a scale from 0 to 5.

The value 0 corresponds to a very whitening composition while the value 5 corresponds to a composition with very low whiteness.

The results are recorded in the following table (I):
Table (I)

<tb><SEP> Formula <SEP> x% <SEP> lb
<tb> A <SEP> (comparative) <SEP> 0 <SEP> 2
<tb><SEP> B <SEP> 0.2 <SEP> 2.9
<tb><SEP> C <SEP> 0.5 <SEP> 2,8
<tb><SEP> D <SEP> j = <SEP><SEP> 1 <SEP> 3,6
<tb><SEP> E <SEP> 2 <SEP> 3,7
<Tb>
These results clearly show that the introduction of deformable hollow microspheres of an expanded copolymer of vinylidene chloride and of acrylonitrile or of vinylidene chloride, of acrylonitrile and of methacrylate in a composition comprising a titanium oxide decreases significantly. bleaching of the composition when applied to the skin.

EXAMPLE 2
The following composition gives a concrete example of a high protection anhydrous sunscreen according to the invention. The amounts are expressed as% by weight relative to the total weight of the composition
Phase A: oxypropylenated butyl alcohol 14 OP sold under the trade name Ucon Fluid AP by Amerchol 12% (emulsifier) - isopropyl palmitate sold under the trade name Estol 1517 by Unichema 12% - hydrogenated castor oil sold under the trade name Cutina HR by Henkel 7.5% - glycerol monostearate sold under the trade name Tegin 90 by Goldschmidt 0.25%
Phase B: - titanium oxide sold under the trade name MT 100T by Tayca 20% - magnesium silicate sold under the trade name Talc Luzenac 15 M00 by Luzenac 5% - expanded microspheres of copolymer vinylidene chloride / acrylonitrile / methyl methacrylate containing isobutane sold under the trade name Expancel 551 DE by Nobel Casto 0.5% - hydrogenated polydecene (PM 549) sold under the trade name Silkflo S 366 NF by Albemarle qs 100%
This cream was carried out as follows: phase A was heated to 90 ° C. in order to homogenize it, then the pigment paste was prepared by mixing titanium oxide with hydrogenated polydecene. talc and then Expancel The phase B thus carried out was heated to 90 ° C. Then the two phases A and B were mixed with Rayneri Once the mixture had been solidified, the mixture was again heated to 90 ° C. The Turrax mixture was then rotated for 10 minutes. The cream was then allowed to cool to room temperature with Rayneri stirring.

This cream whitens very weakly when applied to the skin.

Claims (16)

1. Use of Deformable Hollow Particles, in a Cosmetic and / or Dermatological Composition Containing Titanium Oxide Pigments, for Reducing or Eliminating Bleaching When Applying this Composition to the Skin, These Hollow Particles Having a Granulometry ranging from 1 μm to 250 μm, and being formed from a copolymer of vinylidene chloride, acrylonitrile and methyl (meth) acrylate, expanded. 2. Use according to claim 1, characterized in that the hollow particles have a particle size less than 100 .mu.m. 3. Use according to claim 1 or 2, characterized in that the hollow particles have a particle size ranging from 10 pm to 60 pm. 4. Use according to the preceding claims, characterized in that the hollow particles have a density ranging from 15 kg / m3 to 200 kg / m3. 5. Use according to claim 4, characterized in that the hollow particles have a density ranging from 40 kg / m3 to 100 kg / m3. 6. Use according to one of the preceding claims, characterized in that the hollow particles represent from 0.1% to 10% by weight of the total weight of the composition. 7. Use according to claim 6, characterized in that the hollow particles represent from 0.3% to 5% by weight of the total weight of the composition. 8. Use according to one of the preceding claims, characterized in that said composition contains at least 5% by weight of titanium oxide, relative to the total weight of the composition. 9. Use according to claim 8, characterized in that said composition contains at least 10% by weight of titanium oxide, relative to the total weight of the composition. 10. Use according to claim 9, characterized in that said composition contains at least 15% by weight of titanium oxide, relative to the total weight of the composition. 11. Use according to one of the preceding claims, characterized in that said composition contains, in addition, at least one adjuvant selected from thickeners, emulsifiers, hydrophilic actives, lipophilic actives, perfumes, preservatives, solvents , dyestuffs. 12. Process for reducing or eliminating bleaching during the application of a cosmetic and / or dermatological composition containing titanium oxide pigments, comprising introducing into the composition deformable hollow particles having a particle size ranging from 1 μm to 250 m and being formed of a copolymer of vinylidene chloride, acrylonitrile and methyl (meth) acrylate. 13. The method of claim 12, characterized in that the hollow particles have a particle size less than 100 .mu.m. 14. The method of claim 12 or 13, characterized in that the hollow particles have a particle size ranging from 10 pm to 60 pm. 15. Method according to one of claims 12 to 14, characterized in that the hollow particles have a density ranging from 15 kg / m3 to 200 kg / m3. 16. Method according to one of claims 12 to 15, characterized in that the hollow particles have a density ranging from 40 kg / m3 to 100 kg / m3.