FR3080992A1 - SOLID EXFOLIANT COSMETIC COMPOSITION - Google Patents

Abstract

The invention relates to a solid composition comprising, in an aqueous phase, exfoliation particles, a superabsorbent sodium polyacrylate polymer and an acid group modified starch. Application to the care of the skin.

Description

The subject of the present invention is a solid exfoliating composition comprising exfoliating particles, a superabsorbent polymer and a modified starch, as well as a skin care process using such a composition.

The purpose of the exfoliating compositions is to remove, by mechanical rubbing action, the dead cells from the surface layers of the epidermis, in order to leave the skin smooth, to accelerate the cell renewal of the skin and to improve the penetration of cosmetic active ingredients in the epidermis.

The majority of exfoliating products have a fluid texture, more or less thick, to facilitate their application on the skin, and are rinsable with water to remove the deposit that remains after application and massage on the skin. However, when the texture of the product is too fluid, this creates a difficulty in correctly and homogeneously spreading the composition over the surface of the skin to be treated.

It is therefore desirable to be able to have other galenicals with exfoliating products while exhibiting good cosmetic properties. It is also desirable to have exfoliating products which can be easily removed after their application to the skin without using a rinsing step with water.

The inventors unexpectedly discovered that a composition in solid form (or thick paste) can be obtained with an aqueous composition containing exfoliating particles, a superabsorbent sodium polyacrylate polymer and a modified starch thickener as described above. after.

The composition spreads easily on the skin, allows good exfoliation of the skin surface during mechanical friction during spreading. The composition is easily removed in the dry without adding water and without leaving any residue on the skin surface: after removal of the applied composition, the surface of the treated skin is clean and soft. In addition, the composition has good stability, in particular after storage for one month at 25 ° C.: the exfoliating particles remain well distributed homogeneously in the composition without agglomeration or decantation.

More specifically, the invention relates to a solid cosmetic composition comprising, in an aqueous phase, exfoliating particles, a superabsorbent polyacrylate sodium polymer, a modified starch as described below.

The subject of the invention is also a method of non-therapeutic cosmetic treatment of the skin comprising the application to the skin of a composition as described above, then spreading of the composition and its elimination by friction, in particular with the fingers . The process can be carried out without rinsing step with water after the step of applying the composition to the skin.

According to the present invention, the term "solid composition" means a composition that does not flow under its own weight after 1 minute at a temperature of 25 ° C.

The composition according to the invention comprises exfoliating particles.

By "exfoliating particles" is meant solid and abrasive particles capable of performing, when applied to the skin within an exfoliating composition, a mechanical exfoliation (also called exfoliation) of the dead cells of the surface layers of the epidermis.

In general, a skin scrub is typically carried out by applying an exfoliating composition to the skin, massaging the skin coated with said composition, then optionally by rinsing said composition. The exfoliating particles then act by friction on the skin. The skin is thus smoothed, the absorption of cosmetic active ingredients and cell renewal are favored.

As exfoliating particles, exfoliating particles of mineral origin can be used, such as sands, rocks, perlite or clays.

As exfoliating particles, it is also possible to use exfoliating particles of plant origin, such as pits, leaves, stems, algae, bark, dried fruit or roots.

As exfoliating particles, it is also possible to use exfoliating particles of organic origin, such as beads based on polyethylene or on wax.

Advantageously, the exfoliating particles have a median size of from 10 to 1500 μm.

By “median size” of the exfoliating particles is meant the median size expressed in median diameter by volume (D [0.5]).

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

Advantageously, the exfoliating particles used in the composition of the invention have a median size of from 10 to 2500 μm, preferably from 25 to 1000 μm, preferably from 100 to 500 μm.

Perlite beads or powder can be used, for example, such as those sold under the name IMERCARE 270P-SCRUB or IMERCARE 400P-SCRUB or IMERCARE 800P-SCRUB by the company Imerys.

Polyethylene beads or powder can also be used, for example, such as those sold under the name Microthene 35 MESH MN 711-20, or Microthene MN 710-20 by the company Equistar or CERAPURE 106C COATHYLENE NB 6081 from the company Shamrock Technologies Dupont or FLOBEADS CL5007 from SUMITOMO SEIKA; polyvinyl chloride powder; pumice stone; crushed fruit kernel hulls such as apricot kernel or nut shell hulls; sawdust, wood flour, cork flour; sunflower flour; loofah powder; glass beads; alumina; fibers; and their mixtures.

The exfoliating particles may be present in the composition according to the invention in a content ranging from 5 to 15% by weight, preferably from 7 to 13% by weight, preferably from 8.5 to 12% by weight, relative to the weight total of said composition.

The composition according to the invention comprises at least one superabsorbent sodium polyacrylate polymer. The term "superabsorbent polymer" means a polymer which, in its dry state, can spontaneously absorb at least 20 times its own weight of aqueous fluid, in particular water and in particular distilled water. Such superabsorbent polymers are described in the book Absorbent polymer technology, Studies in polymer science 8 by L. BRAN NON-PAPPAS and R. HARLAND, Elsevier edition, 1990.

These polymers have a great capacity of absorption and retention of water and aqueous fluids. After absorption of the aqueous liquid, the particles of the polymer thus impregnated with aqueous fluid remain insoluble in the aqueous fluid and thus retain their individual particulate state.

The superabsorbent polymer can have a water absorption capacity ranging from 20 to 2000 times its own weight (i.e. 20 g to 2000 g of water absorbed per gram of absorbent polymer), preferably from 30 to 1500 times, and better from 50 to 1000 times, and in particular from 200 to 800 times. These water absorption characteristics are defined under normal temperature (25 ° C) and pressure (760 mm Hg or 100,000 Pa) conditions and for distilled water. The value of the water absorption capacity of a polymer can be determined by dispersing 0.5 g of polymer (s) in 150 g of a water solution, waiting 20 minutes, filtering the solution absorbed on a 150 µm filter for 20 minutes and weighing the unabsorbed water.

Advantageously, the superabsorbent polymer used in the composition of the invention is in the form of particles. Preferably, the superabsorbent polymer has, in the dry or non-hydrated state, an average size less than or equal to 100 μm, preferably less than or equal to 50 μm, ranging for example from 10 to 100 μm, preferably from 15 to 50 pm, and better from 20 to 30 pm.

The average particle size corresponds to the mass average diameter (D50) measured by laser granulometry or other equivalent method known to those skilled in the art.

These particles, once hydrated, swell forming soft particles having an average size which can range from 10 μm to 1000 μm, preferably from 20 μm to 500 μm, and even more preferably from 50 μm to 400 μm.

Preferably, the superabsorbent polymers used in the present invention are in the form of spherical particles.

The superabsorbent sodium polyacrylate polymer used according to the invention can be chosen from crosslinked sodium polyacrylates such as for example sodium polyacrylate crosslinked with ethylene glycol diglycidyl ether such as that sold under the name "AQUAKEEP® 10 SH-NFC" by the company Sumitomo Seika (INCI name: Sodium acrylates crosspolymer-2 (and) water (and) silica); crosslinked sodium polyacrylate sold under the name "Flocare® GB300" by the company SNF, or that sold under the name Activsoft MS100 by the company Innospec Performance Chemicals.

Preferably, the superabsorbent polymer is chosen from sodium polyacrylate crosslinked with ethylene glycol diglycidyl ether, such as that sold under the name "AQUAKEEP® 10 SH-NFC" by the company Sumitomo Seika.

The superabsorbent sodium polyacrylate polymer may be present in the composition of the invention in an active material content ranging from 0.05 to 0.8% by weight, preferably from 0.1 to 0.6% by weight, preferably ranging from 0.1 to 0.4% by weight, more preferably ranging from 0.1 to 0.3% by weight, relative to the total weight of the composition.

The composition according to the invention comprises a modified starch with a carboxylic acid group chosen from:

(i) starch (C1-C4) carboxyalkyls and their salts (in particular sodium salt) (ii) ether resulting from the reaction of starch and 2-chloroethylaminodipropionic acid.

The starch molecules used in the present invention can originate from all vegetable sources of starch, in particular cereals and tubers; more particularly it may be starches of corn, rice, cassava, barley, potato, wheat, sorghum, peas, oats, tapioca. The starch is preferably obtained from the potato.

The modified starch according to the invention may be a (C1-C4) carboxyalkyl starch, also referred to below as "carboxyalkyl starch". These compounds are obtained by grafting carboxyalkyl groups onto one or more alcohol functions of the starch, in particular by reaction of starch and sodium monochloroacetate in an alkaline medium.

The carboxyalkyl starches are advantageously used in the form of salts and in particular of alkali or alkaline earth metal salts such as Na, K, Li, NH4, a quaternary ammonium or an organic amine such as mono, di or triethanolamine . The (C1-C4) starch carboxyalkyls are preferably carboxymethyl starches.

The carboxymethyl starches preferably comprise units of the following formula:

in which X, which may or may not be covalently linked to the carboxylic unit, denotes a hydrogen atom, an alkali or alkaline earth metal such as Na, K, Li, NH4, a quaternary ammonium or an organic amine such as for example such as mono, di or triethanolamine.

Preferably, X denotes a Na + cation.

The carboxyalkyl starches which can be used according to the present invention are preferably partially or totally crosslinked carboxyalkyl starches.

The carboxyalkyl starches considered according to the invention are more particularly carboxyalkyl starches of potatoes. Thus, the carboxyalkyl starches which can be used according to the present invention are preferably sodium salts of carboxyalkyl starch (INCI name: SODIUM CARBOXYMETHYL STARCH), in particular a sodium salt of carboxymethyl starch such as those sold under the name "PRIMOJEL®" by the company DMV International or "GLYCOLYS®" and "GLYCOLYS® LV" by the Roquette Company.

Ether from the reaction of starch and 2-chloroethylaminodipropionic acid (INCI name: Potato Starch Modified) such as that sold under the name "Structure Solanace" by AkzoNobel Global Personal Care.

According to a preferred mode, the carboxymethyl starches will be used, in particular that under the name "GLYCOLYS®" by the company Roquette.

The modified starch can be present in the composition according to the invention, in a content ranging from 3% to 10% by weight, relative to the total weight of the composition, preferably ranging from 4% to 8% by weight, preferably ranging from 5 to 8% by weight, and more preferably ranging from 5 to 7% by weight.

The composition according to the invention is a cosmetic composition. Cosmetic composition is understood to mean a composition comprising a physiologically acceptable medium, that is to say a medium compatible with keratin materials of human beings such as the skin, the scalp, the hair, the nails.

The composition according to the invention comprises an aqueous phase.

The composition comprises water which can be present in a content ranging from 50% to 80% by weight, relative to the total weight of the composition, preferably ranging from 55% to 75% by weight, and preferably ranging from 60 at 70% by weight.

The composition may comprise ethanol, in particular present in a content ranging from 5 to 12% by weight, relative to the total weight of the composition, preferably ranging from 6 to 10% by weight.

The composition may also comprise a polyol miscible with water at room temperature (25 ° C) notably chosen from polyols having in particular from 2 to 6 carbon atoms, such as glycerin, propylene glycol, 1,3 -propanediol, butylene glycol, 1,2 -pentanediol, hexylene glycol, dipropylene glycol, diethylene glycol, diglycerin. Advantageously, the composition may comprise a diol chosen from 1,2-pentadiol and 1,3 propanediol, and their mixture, in particular in a content ranging from 2 to 8% by weight, preferably ranging from 2 to 6% by weight .

The composition according to the invention may also comprise a spherical filler in particular chosen from polymethyl methacrylate such as those sold under the name COVABEAD® LH85 by the company WACKHERR; polyamide powders such as those sold sold under the name "ORGASOL® 2002 EXS NAT COS" by the company ARKEMA; poly methyl methacrylate / ethylene glycol dimethacrylate powders sold under the name DOW CORNING 5640 MICROSPONGE® SKIN OIL ADSORBER by the company DOW CORNING, GANZPEARL® GMP-0820 by the company GANZ CHEMICAL; polymers of allyl methacrylate / ethylene glycol dimethacrylate sold under the name POLYPORE® L200, POLY-PORE® E200 by the company AMCOL Health and Beauty Solutions Inc.; the powders of ethylene glycol dimethacrylate / lauryl methacrylate copolymer sold under the name POLYTRAP® 6603 by the company Dow Corning; polyurethane powders, such as those sold under the names "PLASTIC POWDER D-400", "PLASTIC POWDER D-800", and "PLASTIC POWDER T-75" by the company TOSHIKI; polymethylsilsesquioxane powders, such as that sold under the name TOSPEARL by the company Momentive Performance Materials; organopolysiloxane elastomer powders coated with silicone resin, in particular silsesquioxane resin, as described for example in US Pat. No. 5,538,793, the content of which is incorporated by reference. Such elastomer powders are sold under the names "KSP-100", "KSP-101", "KSP-102", "KSP-103", "KSP104", "KSP-105" by the company Shin Etsu, and have the INCI name "vinyl dimethicone / methicone silsesquioxane Crosspolymer".

silica powders such as those sold under the name SILICA BEADS SB700 by the company MYOSHI, SUNSPHERE® H51, SUNSPHERE® H33 by the company ASAHI GLASS; and their mixtures.

According to a preferred embodiment of the invention, the composition comprises less than 1% by weight of oil, relative to the total weight of the composition, or even is free of oil.

Advantageously, the composition according to the invention has a hardness, at 20 ° C., ranging from 1 to 4 kPa, preferably ranging from 1.5 to 4 kPa, preferably ranging from 2 to 3.5 kPa, more preferably ranging from 2 , 2 to 3.5 kPa.

The hardness of the composition is measured at 20 ° C according to the following protocol:

The composition is packaged in a metal pot 75 mm in diameter and 15 mm deep. The surface is smoothed to the brim using a leveling knife. The sample thus prepared is left at least for 10 min at rest under a bell at room temperature.

The compression force is measured with the TA XT Plus texturometer and the Texture Expert Exceed software. The mobile used is the 12 mm diameter stainless steel cylinder, with the following parameters:

Mobile lowering speed: 1 mm / s

Measuring speed: 0.5 mm / s

Penetration depth: 5 mm

Relaxation: 10 s

Trigger force: 5 g

Mobile withdrawal speed: 0.1 mm / s

Measurements are made on 3 samples

The value obtained is the maximum force F max expressed in grams (g)

The hardness is calculated according to the equation: D = F max / S

D: hardness in MPa

F ma _X : Maximum measured force expressed in Newton (1N = 101.97 g)

S: Contact surface of the mobile ττγ ² (mm ² )

The subject of the invention is also a process for the preparation of a solid cosmetic composition as described above comprising a step of mixing the exfoliating particles, the superabsorbent sodium polyacrylate polymer, the modified starch and the aqueous phase, such as those described above.

The invention is illustrated in more detail in the following examples. The contents of the ingredients are expressed as a percentage by weight.

Example 1:

An exfoliating composition was prepared in the form of a paste (contents in percentage by weight):

Polymethyl methacrylate powder (SEPIMAT® P from SEPPIC) 2%

1% lufa dried fruit powder

Spruce flour 2%

Sunflower flour 2%

Apricot kernel powder 2.4%

Carboxymethyl sodium starch (Glycolys® from Roquette) * 6%

Crosslinked sodium polyacrylate microspheres (Aquakeep® 10SH-NFC from Sumitomo Seika) 0.24%

Ethanol 8%

Pentane-1,2-diol 3%

Propane-1,3-diol 2%

1,3-butylene glycol 3%

Conservative qs

Water qs 100%

The composition was prepared according to the following procedure:

The crosslinked sodium polyacrylate and the sodium carboxymethyl starch were swollen beforehand in the aqueous phase.

Then we added the other ingredients (powders);

The mixture was then stirred using a turbine.

The composition obtained has a hardness of 2965 Pa measured using the texturometer according to the protocol described above.

The composition obtained is in the form of a thick paste, easy to take with your fingers. The composition is very stable and homogeneous after storage for one month at 25 ° C.

The composition was applied to the skin by spreading it out and massaging the skin. The deposit formed has a dry feel and after spreading and massage, the deposit crumbles and is removed dry from the surface of the skin without leaving a residue. The treated skin has a clean appearance and a good softness to the touch.

Example 2:

An exfoliating composition was prepared in the form of a paste (contents in percentage by weight):

Polymethyl methacrylate powder (SEPIMAT® P from SEPPIC) 2% Lufa dried fruit powder 3%

Spruce flour 2%

0.1% sunflower meal

Apricot kernel powder 2.4%

1% capuacu seed pod

1% argan shell powder

Carboxymethyl sodium starch (Glycolys® from Roquette) * 6.6%

Crosslinked sodium polyacrylate microspheres (Aquakeep® 10SH-NFC from Sumitomo Seika) 0.24%

Ethanol 8%

Pentane-1,2-diol 3%

Propane-1,3-diol 2%

Conservative qs

Water qs 100%

The composition obtained is in the form of a thick paste, easy to take with your fingers. The composition is very stable and homogeneous after storage for one month at 25 ° C.

The composition was applied to the skin by spreading it out and massaging the skin. The deposit formed has a dry feel and after spreading and massage, the deposit crumbles and is removed dry from the surface of the skin without leaving a residue. The treated skin has a clean appearance and a good softness to the touch.

Claims (14)

1. Solid cosmetic composition comprising, in an aqueous phase, exfoliating particles, a superabsorbent sodium polyacrylate polymer, a modified starch chosen from (i) the (C1-C4) carboxyalkyl starch and their salts, (ii) ethers resulting from the reaction of starch and 2-chloroethylaminodipropionic acid. 2. Composition according to the preceding claim, characterized in that the exfoliating particles are chosen from perlite powder, polyethylene powder, polyvinyl chloride powder, pumice stone, ground apricot kernels, ground peanuts nut shells, sawdust, wood flour, cork flour, sunflower flour, loofah powder, glass beads, alumina, fiber; and their mixtures. 3. Composition according to one of claims 1 or 2, characterized in that the exfoliating particles have a median size of from 10 to 2500 pm, preferably from 25 to 1000 pm, preferably from 100 to 500 pm. 4. Composition according to any one of the preceding claims, carcatized in that the exfoliating particles are present in a content ranging from 5 to 15% by weight, preferably from 7 to 13% by weight, preferably from 8.5 to 12 % by weight, relative to the total weight of said composition. 5. Composition according to any one of the preceding claims, characterized in that the superabsorbent sodium polyacrylate polymer is chosen from crosslinked sodium polyacrylate, preferably crosslinked with ethylene glycol diglycidyl ether. 6. Composition according to any one of the preceding claims, characterized in that the superabsorbent sodium polyacrylate polymer is present in a content ranging from 0.05 to 0.8% by weight, preferably from 0.1 to 0.6 % by weight, preferably ranging from 0.1 to 0.4% by weight, more preferably ranging from 0.1 to 0.3% by weight, relative to the total weight of the composition. 7. Composition according to any one of the preceding claims, characterized in that the modified starch is chosen from carboxymethyl starch, preferably from the sodium salts of carboxymethyl starch. 8. Composition according to any one of the preceding claims, characterized in that the modified starch is present in a content ranging from 3% to 10% by weight, relative to the total weight of the composition, preferably ranging from 4% to 8% by weight, preferably ranging from 5 to 8% by weight, and more preferably ranging from 5 to 7% by weight. 9. Composition according to any one of the preceding claims, characterized in that it comprises water in a content ranging from 50% to 80% by weight, relative to the total weight of the composition, preferably ranging from 55 % to 75% by weight, and preferably ranging from 60 to 70% by weight. 10. Composition according to any one of the preceding claims, characterized in that it comprises from 5 to 12% by weight of ethanol, relative to the total weight of the composition, preferably from 6 to 10% by weight. 11. Composition according to any one of the preceding claims, characterized in that it comprises a diol chosen from 1,2-pentanediol and 1,3 propanediol, and their mixture, in particular present in a content ranging from 2 to 8 % by weight, preferably ranging from 2 to 6% by weight. 12. Composition according to any one of the preceding claims, characterized in that it has a hardness, at 25 ° C, ranging from 1 to 4 kPa, preferably ranging from 1.5 to 4 kPa, preferably ranging from 2 to 3.5 kPa, more preferably ranging from 2.2 to 3.5 kPa. 13. A non-therapeutic cosmetic treatment treatment for skin care comprising the application to the skin of a composition according to any one of the preceding claims, then spreading of said composition and its elimination by friction, in particular with the fingers . 14. Method according to the preceding claim, characterized in that it is carried out without rinsing step with water after the step of applying the composition to the skin.