WO2019219684A1 - Solid exfoliating cosmetic composition - Google Patents

Abstract

The invention relates to a solid composition comprising, in an aqueous phase, exfoliating particles, a superabsorbent alkali metal polyacrylate polymer, preferably sodium, and an acid-group-modified starch. The invention applies to skin care.

Description

 Solid exfoliating cosmetic composition

The present invention provides an exfoliating solid composition comprising exfoliating particles, a superabsorbent polymer and a modified starch, and a skin care method using such a composition.

The purpose of the exfoliating compositions is to remove, by mechanical rubbing action, the dead cells from the superficial layers of the epidermis, in order to leave the skin smooth, to accelerate the cellular renewal of the skin and to improve the penetration of the skin. cosmetic active 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 product texture is too fluid, it creates a difficulty in spreading the composition correctly on the surface of the skin to be treated correctly and homogeneously.

 I! It is therefore desirable to have other galenic exfoliating products while having good cosmetic properties. It is also desirable to have exfoliating products that can be easily removed after they are applied to the skin without using a rinsing step with water.

 The inventors have unexpectedly discovered that a composition in solid (or thick) form can be obtained with an aqueous composition containing exfoliating particles, an alkali metal polyacrylate polymer, preferably sodium, superabsorbaht and a modified starch thickener as described below.

The composition spreads easily on the skin, allows good exfoliation of the skin surface during mechanical friction during spreading. The composition is easily removed dry without adding water and leaving no residue on the surface of the skin: after removal of the applied composition, the surface of the treated skin is clean and soft. In addition, the composition has good stability, particularly after a stock- age from one month to 25 ^P C: the exfoliating particles are very homogeneously distributed in the composition without agglomeration or settling.

 More specifically, the object of the invention is a solid cosmetic composition comprising, in an aqueous phase, exfoliant particles, a superabsorbent alkali metal (preferably sodium) polyacrylate polymer, a modified starch as described below.

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

SUBSTITUTE SHEET (RULE 26) According to the present invention, the term "solid composition" means a composition which 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 scrubbing) of the dead cells of the superficial layers. of the epidermis.

In general, a scrub of the skin is typically performed by applying an exfoliating composition to the skin, by 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 cellular renewal are favored.

Exfoliating particles may be exfoliating particles of mineral origin, such as sands, rocks, perlite or clays.

As exfoliating particles, exfoliating particles of vegetable origin, such as cores, leaves, stems, algae, bark, dried fruits or roots, may also be used.

As exfoliating particles, it is also possible to use exfoliating particles of organic origin, such as beads based on polyethylene or 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 as the median diameter by volume (D [0.5]).

The median size of the exfoliating particles can be measured by static light scattering using a commercial MasterSizer 2000 type particle size analyzer from Malvern. The data is processed on the basis of Mie scattering theory. This theory, which is accurate 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 10 to 2500 μm, preferably 25 to 1000 μm, preferably 100 to 500 μm. For example, beads or perlite powder, such as those marketed under the name IMERCARE 270P-SCRUB or IMERCARE 400P-SCRUB or IMERCARE 800P-SCRUB by Imerys, may be used.

 It is also possible to use for example the balls or the polyethylene powder, such as those sold under the name Microthene MESH MN 71 1-20, 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; hulls of crushed fruit stones such as crushed apricot kernels or nut hulls; sawdust, wood flour, cork flour; sunflower meal; 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 to the total weight of said composition.

The composition according to the invention comprises at least one superabsorbent alkali metal (preferably sodium) polyacrylate polymer. By "superabsorbent polymer" is meant a polymer that is capable of being spontaneously absorbed at least 20 times its own weight of aqueous fluid, in particular water and especially 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 high capacity for absorption and retention of water and aqueous fluids. After absorption of the aqueous liquid, the polymer particles thus impregnated with aqueous fluid remain insoluble in the aqueous fluid and thus maintain their individualized particulate state.

The superabsorbent polymer can have a water absorption capacity ranging from 20 to 2000 times its own weight (ie 20 g to 2000 g absorbed water per gram of absorbent polymer), preferably from 30 to 1500 times, and better 50 to 1000 times, and in particular 200 to 800 times. These water absorption characteristics are defined under normal conditions of temperature (25 ° C) and pressure (760 mmHg or 100000 Pa) 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, while waiting for 20 minutes, filtering the unabsorbed solution on a 150 μm filter for 20 minutes and weighing 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 of 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 μm, and better 20 to 30 μm. The average particle size corresponds to the mean diameter by mass (D50) measured by laser particle size distribution or other equivalent method known to those skilled in the art.

These particles, once hydrated, swell to form soft particles having an average size ranging from 10 pm to 1000 pm, preferably from 20 pm to 500 pm, and even more preferably from 50 pm to 400 pm.

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

The superabsorbent alkali metal polyacrylate polymer are preferably superabsorbent polymers of Na, K, more preferably sodium. As superabsorbent alkali metal polyacrylate polymer used according ivention may be selected 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 Sumitomo Seika (INCI name: Sodium acrylates crosspolymer-2 (and) water (and) silica); cross-linked 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 alkali metal polyacrylate (preferably sodium) crosslinked with ethylene glycol diglycidyl ether, such as that sold under the name AQUAKEEP® 10 SH-NFC by the company Sumitomo Seika .

The superabsorbent alkali metal (preferably 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 containing a carboxylic acid group chosen from:

(i) (C ₁ -C ₄ ) carboxyalkyl starches and their salts (in particular sodium salt)

 (II) the ether resulting from the reaction of starch and 2-chloroethylaminodipropionic acid.

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

The modified starch according to the invention can be a (C ₁ -C ₄ ) carboxyalkyl of starch, hereinafter referred to as "carboxyalkyl starch". These compounds are obtained by grafting carboxyalkyl groups on one or more alcohol functions of the starch, in particular by reaction of starch and alkali metal monochloroacetate such as sodium in alkaline (basic) medium.

The carboxyalkyl starches are advantageously used in the form of salts and in particular of alkali metal or alkaline earth metal salts such as Na, K, Li, NH 4, of a quaternary ammonium or of an organic amine such as mono, di or triethanolamine. The (C1-C4) carboxyalkyl starches are preferably carboxymethyl starches.

The carboxymethyl starches preferably comprise units of the following formula:

dans laquelle X, lie ou non de manière covalente au motif carboxylique, dé- signe un atome d’hydrogène, un métal alcalin ou alcalinoterreux tels que Na, K, Li, NH4, un ammonium quaternaire ou une amine organique telle que parexemple telle que la mono, di ou triéthanolamine.

wherein X, whether or not covalently attached to the carboxylic unit, means a hydrogen atom, an alkali metal 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 an Na + cation.

The carboxyalkyl starches which can be used according to the present invention are preferably cross-linked carboxyalkyl starches, partially or totally.

The carboxyalkyl starches considered according to the invention are more particularly potato carboxylyl starches. 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 DMV International so- ciety or "GLYCOLYS ^®" and "GLYCOLYS ^® LV" by Ro quette Company.

The ether resulting from the reaction of starch and 2-chloroethylaminodipropionic acid (Name I CI: Potato Starch Modified) such as that sold under the name "Solanace Structure" by AkzoNobel Global Personal Care.

In a preferred embodiment, use carboxymethylamidons, particularly under the name "GLYCOLYS ^®" by Roquette. The modified starch may 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 from 5 to 8% by weight, and more preferably 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 that is compatible with the keratin materials of human beings such as the skin, the scalp, the hair or the nails.

The composition according to the invention comprises an aqueous phase.

The composition comprises water which may 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% to 60% by weight. 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 furthermore comprise a polyol which is miscible with water at room temperature (25 ° C.), in particular chosen from polyols having in particular from 2 to 6 carbon atoms, such as glycerin, propylene glycol, and the like. , 3-propanediol, butylene glycol, 1,2-pentanediol, hexylene glycol, dipropylene glycol, diethylene glycol, diglycerine. Advantageously, the composition may comprise a diol chosen from 1, 2-pentadiol and 1,3-propanediol, and their mixture, especially 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 furthermore comprise a spherical filler, especially 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; the 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; the allyl polymethacrylate / ethylene glycol dimethacrylate powders sold under the name PolyPore® L200 and Poly-Pore® E200 by Am Col Health and Beauty Solutions Inc.; the ethylene glycol dimethacrylate / lauryl methacrylate copolymer powders 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 TOSHIKI company; polymethylsilsesquioxane powders, such as the product marketed under the name Tospearl by the company Momentive Performance Materials; organopolysiloxane elastomer powders coated with silicone resin, especially silsesquioxane resin, as described, for example, in US Pat. No. 5,538,793, the contents of which are incorporated by reference. Such elastomer powders are sold under the names "KSP-100", "KSP-101", "KSP-102", "KSP-103", "KSP-104", "KSP-105" by the company Shin Etsu, INCI is vinyl dimethicone / methicone silsesquioxane Crosspolymer.

silica powders such as those sold under the name SILICA BEADS SB-700 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 is free of oil.

The composition of the invention may also contain various adjuvants conventionally used in cosmetic compositions, such as anionic, cationic, nonionic, amphoteric or zwitterionic polymers or mixtures thereof, the adjuvant polymers being different from the superabsorbent polymers and modified starches, inorganic thickening agents, penetrating agents, sequestering agents, perfumes, buffers, dispersing agents, nonionic, anionic, cationic or zwitterionic surfactants, film-forming agents, ceramides, and / or preservatives . The adjuvants above are generally present in an amount inclusive for each of them between 0.01 and 20% by weight relative to the weight of the composition.

 Of course, one skilled in the art will take care to choose this or these optional additional compounds in such a way that the advantageous properties intrinsically attached to the composition of the invention are not, or not substantially, impaired by the one or more proposed additions.

According to one particular embodiment of the invention, the composition does not comprise a cationic surfactant chosen from mono (C 1 -C 12) alkyltrimethylammonium halides and di (C 12 -C 24) alkyl dimethylammonium halides, especially in amounts ranging from , 1 and 15% by weight relative to the total weight of the composition. Even more preferentially, the composition of the invention does not comprise cationic surfactants.

According to another particular embodiment of the invention, the superabsorbent polymer is different from a carboxyvinyl polymer, especially at amounts of between 0.1 and 5% by weight relative to the total weight of the composition. More preferentially, the composition of the invention does not comprise a carboxyvinyl polymer. 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, preferentially 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 with a sharp knife. The sample thus prepared is left at least for 10 minutes 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 stainless steel cylinder diameter 12 mm, with the following parameters:

 Mobile descent speed: 1 mm / s

Measuring speed: 0.5 mm / s

Depth penetration: 5 mm

Relaxation: 10 s

 Trigger force: 5 g

 Mobile removal speed: 0.1 mm / s

 The 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 _max : Maximum measured force expressed in Newton (1 N = 101, 97 g)

S: contact area of the mobile ur ² (mm ² )

The subject of the invention is also a method for preparing a solid cosmetic composition as described above comprising a step of mixing the exfoliating particles, the superabsorbent alkali metal (preferably sodium) polyacrylate polymer, the modified starch and the the lacing phase, such as those described above.

The invention is illustrated in more detail in the following examples. The contents of the ingredients are expressed in percentage by weight. Example 1

A dough-shaped exfoliating composition (contents in% sided) was prepared:

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

Lufa Dry Fruit Powder 1% Spicy Flour 2% Sunflower Flour 2% Apricot Kernel Powder 2.4%

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

Microspheres of crosslinked sodium polyacrylate

(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:

 Sodium crosslinked polyacrylate and sodium carboxymethyl starch were first swelled in the aqueous phase.

 Then the other ingredients (powders) were added;

 The mixture was then stirred with 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 consistent paste, easy to take with the fingers. The composition is well stable and homogeneous after storage for one month at 25 ° C.

The composition was applied to the skin by spreading 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 good softness to the touch. Example 2

A dough-shaped exfoliating composition (contents in% sided) was prepared:

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

Lufa dry fruit powder 3%

2% spruce flour

Sunflower meal 0.1%

2.4% apricot kernel powder

Capuacu seed lump 1%

1% argan shell powder

Sodium carboxymethyl starch (Glycolys® from Roquette) ^* 6.6%

Microspheres of crosslinked sodium polyacrylate

 (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 consistent paste, easy to take with the fingers. The composition is well stable and homogeneous after storage for one month at 25 ° C.

The composition was applied to the skin by spreading 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 good softness to the touch.

Claims

1. A solid cosmetic composition comprising, in an aqueous phase, exfoliating particles, a polyacrylate polymer of alkali metals, preferably sodium, superabsorbent, a modified starch selected from (i) carboxyalkyl (C1-C4) starch and their salts, (ii) the ethers derived 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, crushed stone. nut hulls, sawdust, wood flour, cork flour, sunflower meal, 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 10 to 2500 pm, preferably 25 to 1000 pm, preferably 100 to 500 pm. 4. Composition according to any one of the preceding claims, carcatérisée 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 polyacrylate polymer of alkali metals (preferably sodium) superabsorbent is selected from alkali metal polyacrylate, such as sodium, crosslinked, preferably crosslinked with the ethylene glycol diglycidyl ether. 6. Composition according to any one of the preceding claims, characterized in that the superabsorbent alkali metal (preferably sodium) polyacrylate polymer is present in a content ranging from 0.05 to 0.8% by weight, preferably from 0 to , 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 alkali metal salts, such as sodium, 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% at 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 % 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. 1 1. 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. weight, preferably 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 from 2 to 3.5 kPa, more preferably ranging from 2.2 to 3.5 kPa. 13. Composition according to any one of the preceding claims, characterized in that it does not comprise a cationic surfactant chosen from mono (C12-C24) alkyltrimethylammonium halides and di (C12-C24) alkyl dimethylammonium halides, especially from amounts of between 0.1 and 15% by weight relative to the total weight of the composition; more preferably, said composition does not comprise cationic surfactants. 14. Composition according to any one of the preceding claims, characterized in that the superabsorbent polymer is different from a carboxyvinyl polymer, especially in amounts of between 0.1 and 5% by weight relative to the total weight of the composition. tion; preferentially, said composition does not comprise carboxyvinyl polymer. 15. A method of non-therapeutic cosmetic skin care treatment comprising applying to the skin a composition according to any one of the preceding claims, then spreading said composition and removing it by friction, in particular with your fingers. 16. Process according to the preceding claim, characterized in that it is carried out without a rinsing step with water after the step of applying the composition to the skin.