Cosmetic composition comprising polyglutamic acid

Abstract

The present invention relates to a composition, comprising: (a) at least one polyglutamic acid or a salt thereof; (b) at least one neutralized poly(meth)acrylic acid polymer; and (c) at least one hydrophobic inorganic filler. The composition according to the present invention is stable and can provide good spreadability during application and smoothness after application.

Description

[0001] DESCRIPTION

[0002] TITLE OF INVENTION

[0003] COSMETIC COMPOSITION COMPRISING POLYGLUTAMIC ACID

[0004] TECHNICAL FIELD

[0005] The present invention relates to a composition, preferably a cosmetic composition, and more preferably a skin cosmetic composition, which is stable and can provide a good feeling in use.

[0006] BACKGROUND ART

[0007] There are many needs for cosmetic products which include insoluble powders but are stable without causing sedimentation of the insoluble powders.

[0008] In addition, imparting good feeling in use to keratinous substances, such as skin, is one of the key features of cosmetic products, especially skin cosmetic products. In particular, good spreadability with less friction feeling during application, and smoothness after application are often required for consumer satisfaction.

[0009] DISCLOSURE OF INVENTION

[0010] An objective of the present invention is to provide a stable composition which can provide good spreadability during application and smoothness after application.

[0011] The above objective of the present invention can be achieved by a composition, preferably a cosmetic composition, and more preferably a skin cosmetic composition, comprising:

[0012] (a) at least one polyglutamic acid or a salt thereof;

[0013] (b) at least one neutralized poly(meth)acrylic acid polymer; and

[0014] (c) at least one hydrophobic inorganic filler.

[0015] The amount of the (a) polyglutamic acid(s) or salt(s) thereof in the composition according to the present invention may range from 0.001% to 3% by weight, preferably from 0.005% to 1% by weight, and more preferably from 0.01% to 0.5% by weight, relative to the total weight of the composition.

[0016] The (b) neutralized poly(meth)acrylic acid polymer may be totally or partially neutralized, and preferably partially neutralized.

[0017] The (b) neutralized poly(meth)acrylic acid polymer may be totally or partially in the form of a salt, preferably a metal salt, more preferably an alkaline metal salt, and even more preferably a sodium salt. the (b) neutralized poly(meth)acrylic acid polymer may have a repeating unit represented by the following formula (I): -[CH(R1)-C(R2)(COO-M+)]- (I) wherein

[0018] R1and R2, identical or different, represent a hydrogen atom or a (C1-C6)alkyl group such as methyl, preferably R1and R2represent a hydrogen atom; and

[0019] M+represents H+or a cationic counterion, preferably an alkali metal cation, alkaline earth metal cation or ammonium ion, more preferably M+represents an alkali metal cation such as sodium cation.

[0020] The (b) neutralized poly(meth)acrylic acid polymer may be a crosslinked homopolymer.

[0021] The amount of the (b) neutralized poly(meth)acrylic acid polymer(s) in the composition according to the present invention may range from 0.01% to 5% by weight, preferably from 0.05% to 4% by weight, and more preferably from 0.1% to 3% by weight, relative to the total weight of the composition.

[0022] The (c) hydrophobic inorganic filler may be selected from hydrophobically-modified metal oxides, and preferably from hydrophobically-modified silica, titanium oxide, zinc oxide and a mixture thereof.

[0023] The (c) hydrophobic inorganic filler may be selected from hydrophobic silicas, preferably from hydrophobic silica aerogel particles, and more preferably from hydrophobic aerogels of silica silylate.

[0024] The amount of the (c) hydrophobic inorganic filler(s) in the composition according to the present invention may range from 0.01% to 3% by weight, preferably from 0.05% to 1% by weight, and more preferably from 0.1% to 0.5% by weight, relative to the total weight of the composition.

[0025] The composition according to the present invention may further comprise (d) at least one hyaluronic acid ingredient selected from the group consisting of hyaluronic acid, hyaluronic acid salts, hyaluronic acid derivatives, hyaluronic acid derivative salts, and mixtures thereof.

[0026] Tire amount of the (d) hyaluronic acid ingredient(s) in the composition according to the present invention may range from 0.001% to 3% by weight, preferably from 0.005% to 1% by weight, and more preferably from 0.01% to 0.5% by weight, relative to the total weight of the composition.

[0027] The composition according to the present invention may further comprise (e) at least one polysaccharide, preferably the (e) polysaccharide is selected from the group consisting of an algal extract, a gum and a cellulose derivative, sclerotium gum, xanthan gum, fermented polysaccharides such as Biosaccharide Gum-1 , Biosaccharide Gum-2 and Biosaccharide-4, and mixtures thereof, and more preferably the (e) polysaccharide is selected from the group consisting of sclerotium gum, xanthan gum, fermented polysaccharides such as Biosaccharide Gum-1, Biosaccharide Gum-2 and Biosaccharide-4, and mixtures thereof.

[0028] The amount of the (e) polysaccharide(s) in the composition according to the present invention may range from 0.001% to 3% by weight, preferably from 0.005% to 2% by weight, and more preferably from 0.01% to 1% by weight, relative to the total weight of the composition.

[0029] The present invention also relates to a cosmetic process for treating a keratin substance, comprising the step of applying the composition according to the present invention to the keratin substance.

[0030] BEST MODE FOR CARRYING OUT THE INVENTION

[0031] After diligent research, the inventors have discovered that it is possible to provide a stable composition which can provide good spreadability during application and smoothness after application.

[0032] Thus, one aspect of the present invention is a composition comprising:

[0033] (a) at least one polyglutamic acid or a salt thereof;

[0034] (b) at least one neutralized poly(meth)acrylic acid polymer; and

[0035] (c) at least one hydrophobic inorganic filler.

[0036] The composition according to the present invention is stable and can provide good spreadability during application and smoothness after application.

[0037] The composition according to the present invention is suitable for skin care.

[0038] The composition according to the present invention is stable such that no or little sedimentation of the (c) hydrophobic inorganic filler is caused in the composition.

[0039] The composition according to the present invention is stable just after the preparation of the composition and a long time after the preparation of the composition, even under elevated temperature. Therefore, the composition according to the present invention is stable over time, and can be stored for a long period of time even under hot conditions, for example, in summer.

[0040] Furthermore, the composition according to the present invention can provide a good feeling in use, in particular good spreadability during application and smoothness after application.

[0041] The good spreadability here means easiness to spread with less friction feeling, i.e., smooth spreading. Thus, the composition according to the present invention is preferable for a skin cosmetic product.

[0042] The smoothness after application here means smooth feeling to touch, without or reduced stickiness, after application. The term “stickiness” means a property which provides a tacky feeling to the skin. Thus, the composition according to the present invention is preferable for a skin cosmetic product.

[0043] The (a) polyglutamic acid or a salt thereof is slimy, water-absorbing and film-forming. Thus, the composition according to the present invention including the (a) polyglutamic acid or a salt thereof can have a good fluidity which can contribute to good spreadability with less friction feeling during application. On the other hand, after application, the (a) polyglutamic acid or a salt thereof can contribute to long-lasting moisturizing feeling and smoothness.

[0044] The (c) hydrophobic inorganic filler in the composition according to the present invention can also contribute to smoothness after application of the composition.

[0045] In addition, the (c) hydrophobic inorganic filler can be dispersed evenly in the composition according to the present invention due to the action of the (b) neutralized poly(meth)acrylic acid polymer such that the (c) hydrophobic inorganic filler makes a network structure like a film. It is believed that the network structure formed by the (c) hydrophobic inorganic filler will contribute to smooth spreading with less friction feeling during application of the composition according to the present invention.

[0046] Also, the (c) hydrophobic inorganic filler may provide mattifying effects if it is capable of absorbing oil or sebum. The composition according to the present invention can also provide additional effects.

[0047] In general, a use of a relatively large amount of synthetic polymer(s) in a composition may cause the formation of particles in the form of noodles after application of the composition due to the aggregation of the synthetic polymer(s). The formation of the noodles is not preferable in some cases.

[0048] However, even if the composition according to the present invention includes a relatively large amount of the (b) neutralized poly(meth)acrylic acid polymer(s), the composition according to the present invention can suppress the formation of noodles after application.

[0049] If the composition according to the present invention further includes the (d) hyaluronic acid ingredient, the yield stress of the composition according to the present invention can be reduced furthermore, which can enhance furthermore the spreadability of the composition according to the present invention. In addition, the (d) hyaluronic acid ingredient can enhance furthermore moisturizing effects.

[0050] If the composition according to the present invention further includes water, the composition according to the present invention can also provide good hydration effects as well as refreshing feeling. Also, the composition according to the present invention can provide moisturizing feeling as if the water were penetrate deeper into the skin, so that the inner of the skin were moisturized well.

[0051] Hereinafter, the present invention will be explained in a more detailed manner.

[0052] [Composition]

[0053] The composition according to the present invention comprises:

[0054] (a) at least one polyglutamic acid or a salt thereof;

[0055] (b) at least one neutralized poly(meth)aciylic acid polymer; and

[0056] (c) at least one hydrophobic inorganic filler.

[0057] (Polyglutamic Acid or Salt Thereof)

[0058] The composition according to the present invention comprises (a) at least one polyglutamic acid or a salt thereof. A single type of polyglutamic acid or a salt thereof may be used, while two or more different types of polyglutamic acids or salts thereof may be used in combination.

[0059] The (a) polyglutamic acid or a salt thereof may have a chemical structure represented by the following chemical formula (1):

[0060] ROOC-CH2CH2-CH(-COOR)-NH-[CO-CH2CH2-CH(-COOR)-NH-]n-CO-CH2CH2-CH(-

[0061] COOR)-NH2(1) in which R independently denotes a hydrogen atom, an alkali metal atom such as sodium atom and potassium atom, or an ammonium group such as tetramethylammoium group and tetraethylammonium group, and n is an integer of 2 or more, preferably 4 or more, and more preferably 6 or more. The polyglutamic acid or a salt thereof represented by the above chemical formula (1) may be referred to as γ-polyglutamic acid or a salt thereof, because the carboxylic group at the γ-position and the amino group at the a-position form a peptide bond.

[0062] It may be preferable that the molecular weight of the (a) polyglutamic acid or a salt thereof be 1000 or more, and that the degree of polymerization be 8 or more (“n” in the above chemical formula (1) is 6 or more).

[0063] It may be more preferable that the molecular weight of the (a) polyglutamic acid or a salt thereof be 100,000 or more, and that the polymerization degree be 770 or more (“n” in the above chemical formula (1) is 768 or more).

[0064] It may be even more preferable that the molecular weight of the (a) poly glutamic acid or a salt thereof be 500,000 or more, and that the polymerization degree be 3840 or more (“n” in the above chemical formula (1) is 3838 or more).

[0065] There is no upper limit for the molecular weight of the (a) polyglutamic acid or a salt thereof.

[0066] However, the molecular weight of the (a) poly glutamic acid or a salt thereof may be 5000000 or less, and the degree of polymerization may be 38500 or less (“n” in the above chemical formula (1) is 38498 or less), and preferably the molecular weight the (a) polyglutamic acid or a salt thereof may be 3000000 or less, and the degree of polymerization may be 23080 or less (“n” in the above chemical formula (1) is 23078 or less).

[0067] The glutamic acid that is a constituent amino acid of the (a) polyglutamic acid or a salt thereof may be D-form, L-form or a racemic form. However, in consideration of the availability in the market, biocompatibility and biodegradability, the use of polyglutamic acid composed only of L- form glutamic acids or polyglutamic acid composed of a mixture of L- and D- form glutamic acids may be preferable. However, polyglutamic acid composed of D-form glutamic acids having the same effect and low degradability can also be used.

[0068] The production method of the (a) polyglutamic acid or a salt thereof is not particularly limited. For example, an organic synthesis method using a peptide synthesizer, an organic synthesis method by polymerization reaction of glutamate N-carboxylic anhydride, an organic synthesis by polymerization reaction of N-benzyloxycarbonyl glutamic anhydride. On the other hand, microorganisms belonging to the genus Bacillus having the ability to produce γ-polyglutamic acid (particularly Bacillus subtilis, Bacillus anthracis, Bacillus licheniformis, Bacillus licheniformis, Bacillus megaterium having the ability to produce γ-polyglutamic acid) can also be used for fermentation methods for producing the (a) polyglutamic acid or a salt thereof.

[0069] As a medium used in the fermentation method, in addition to a natural medium composed of natural products such as shochu distillation waste liquid medium and soybean extract medium, any synthetic medium or any semi-synthetic medium constituted by any one of the following ingredients: carbon sources such as glucose, fructose, galactose, sucrose, maltose, mannose, lactose, glycerol, and starch; inorganic nitrogen sources such as ammonium sulfate, ammonium phosphate and ammonium hydrochloride; organic nitrogen sources such as glutamic acid or salts thereof, aspartic acid or salts thereof major inorganic salts such as sodium chloride, magnesium sulfate, monopotassium phosphate, phosphorus and disodium phosphate; trace inorganic salts containing atoms such as iron, copper, zinc, cobalt, nickel, boron, manganese, molybdenum, tin, selenium, silicon, arsenic, vanadium, chromium, and fluorine; vitamins such as biotin, nicotinic acid amide, calcium pantothenate, thiamine, riboflavin and pyridoxine hydrochloride; organic acids such as citric acid, tartaric acid, malic acid, and glycolic acid, and natural product extracts such as yeast extract, meat extract, potato extract, tomato extract, and soybean peptide, at any concentration may be used.

[0070] The culture conditions of the microorganism may be set in the range of from 20°C to 37°C with respect to the temperature, and may be further controlled during the microorganism growth process and polyglutamic acid production process. The pH may be set in the range of from 5.0 to 8.0, and may be further controlled during the microorganism growth process and polyglutamic acid production process.

[0071] As a method for extracting and purifying the (a) polyglutamic acid or a salt thereof from the culture solution after completion of the culture, known methods such as an acid precipitation method, a solvent precipitation method, and a membrane purification method can be arbitrarily selected.

[0072] It is preferable, as the (a) polyglutamic acid or a salt thereof, to use polyglutamic acid or an alkaline metal salt thereof such as sodium poly glutamate.

[0073] As the (a) polyglutamic acid or a salt thereof, a commercially available product may be used. As examples of the (a) polyglutamic acid or a salt thereof, mention may be made of, Hyafactor™- PGA-HM sold by Bloomage Biotechnology Co., Ltd. in China, and Bio-PGA Solution HE, HB, LB and LE, and Bio PGA Na powder, sold by Ichimaru Pharcos in Japan.

[0074] The amount of the (a) poly glutamic acid(s) or salt(s) thereof in the composition according to the present invention may be 0.001% by weight or more, preferably 0.005% by weight or more, and more preferably 0.01% by weight or more, relative to the total weight of the composition.

[0075] On the other hand, the amount of the (a) polyglutamic acid(s) or salt(s) thereof in the composition according to the present invention may be 3% by weight or less, preferably 1% by weight or less, and more preferably 0.5% by weight or less, relative to the total weight of the composition.

[0076] Thus, the amount of the(a) polyglutamic acid(s) or salt(s) thereof in the composition according to the present invention may range from 0.001% to 3% by weight, preferably from 0.005% to 1% by weight, and more preferably from 0.01% to 0.5% by weight, relative to the total weight of the composition.

[0077] (Neutralized Poly(meth)acrylic Acid Polymer)

[0078] The composition according to the present invention comprises (b) at least one neutralized poly(meth)acrylic acid polymer. A single type of neutralized poly(meth)acrylic acid polymer may be used, while two or more different types of neutralized poly(meth)acrylic acid polymers may be used in combination.

[0079] The (b) neutralized poly(meth)acrylic acid polymer may have a water absorbing property. Therefore, the (b) neutralized poly(meth)acrylic acid polymer can be a water absorbing polymer.

[0080] In one specific embodiment of the present invention, the (b) neutralized poly(meth)acrylic acid polymer may have a water absorbing capacity of 10 g or more, preferably 20 g or more, and more preferably 50 g or more, and / or of 2,000 g or less, preferably 1,500 g or less, and more preferably 1,000 g or less, relative to 1 g of the polymer at 25°C and 1 atm.

[0081] The (b) neutralized poly(meth)acrylic acid polymer may be provided in the form of particles, and preferably in the form of spherical particles. The average primary particle size as D50of the neutralized poly(meth)acrylic acid polymer is not particularly limited, but in general is 0.1 μm or more, preferably 0.5 μm or more, and more preferably 1 μm or more, and / or is 200 μm or less, preferably 100 μm or less, more preferably 50 μm or less. The term “D50” herein means the particle size at which 50% by volume of the particles based on the total volume of the particles are smaller than or equal to D50and 50% by volume of the particles based on the total volume of the particles are larger than D50. The D50value can be determined by laser diffraction, for example, using a laser diffraction particle size distribution analyzer, such as Mastersizer 2000 by Malvern Corp.

[0082] The (b) neutralized poly(meth)acrylic acid polymer may be water-soluble. Therefore, the (b) neutralized poly(meth)acrylic acid polymer may be included in the aqueous phase of the composition according to the present invention, if the composition according to the present invention includes water.

[0083] The (b) neutralized poly(meth)acrylic acid polymer may be neutralized totally or partially.

[0084] Preferably, the (b) neutralized poly(meth)acrylic acid polymer is partially neutralized. The (b) neutralized poly(meth)acrylic acid polymer may be totally or partially in the form of a salt, preferably a metal salt, more preferably alkaline metal salt, and even more preferably a sodium salt. The molar ratio of neutralized parts to un-neutralized parts is not particularly limited, but in general 10 mol% or more, 20 mol% or more, 30 mol% or more, or 40 mol% or more, and / or 90 mol% or less, 80 mol% or less, 70 mol% or less, or 60 mol% or less.

[0085] The (b) neutralized poly(meth)acrylic acid polymer may be a homo- or copolymer. Preferably, the (b) neutralized poly(meth)acrylic acid polymer is a homopolymer.

[0086] The (b) neutralized poly(meth)acrylic acid polymer may have a repeating unit represented by the following formula (I): -[CH(R1)-C(R2)(COO-M+)]- (I) wherein

[0087] R1and R2, identical or different, represent a hydrogen atom or a (C1-C6)alkyl group such as methyl, preferably R1and R2represent a hydrogen atom; and

[0088] M+represents H+or a cationic counterion, preferably an alkali metal cation, alkaline earth metal cation or ammonium ion, more preferably M+represents an alkali metal cation such as sodium cation.

[0089] The repeating number of the above repeating unit according to the formula (I) is 2 or more.

[0090] The (b) neutralized poly(meth)acrylic acid polymer with a repeating unit according to the formula (I) may be derived from the polymerization of several monomers, identical (in which case it is homopolymer) or different (in which case it is copolymers) selected from those of formula (la):

[0091] HC(R1) =C(R2)-COO-M+(la) wherein R1, R2and M+are as defined above, in the presence of at least one polymerization initiator (e.g., a UV-initiator) to lead to polymers of formula (I) as defined above.

[0092] The (b) neutralized poly(meth)acrylic acid polymer may be crosslinked.

[0093] The closslinking of the (b) neutralized poly (meth) acrylic acid polymer may be performed by, for example, applying at least one crosslinking agent to the (b) neutralized poly(meth)acrylic acid polymer by spraying.

[0094] In one preferred embodiment of the present invention, the (b) neutralized poly(meth)acrylic acid polymer is a crosslinked homopolymer. Mention may particularly be made of sodium polyacrylate sold under the name of AQUPEC MG N40R, which is crosslinked and partially neutralized and also called a sodium carbomer.

[0095] The amount of the (b) neutralized poly(meth)acrylic acid polymer(s) in the composition according to the present invention may be 0.01% by weight or more, preferably 0.05% by weight or more, and more preferably 0.1% by weight or more, relative to the total weight of the composition.

[0096] On the other hand, the amount of the (b) neutralized poly(meth)acrylic acid polymer(s) in the composition according to the present invention may be 5% by weight or less, preferably 4% by weight or less, and more preferably 3% by weight or less, relative to the total weight of the composition.

[0097] Thus, the amount of the (b) neutralized poly(meth)acrylic acid polymer(s) in the composition according to the present invention may range from 0.01% to 5% by weight, preferably from 0.05% to 4% by weight, and more preferably from 0.1% to 3% by weight, relative to the total weight of the composition.

[0098] (Hydrophobic Inorganic Filler)

[0099] The composition according to the present invention comprises (c) at least one hydrophobic inorganic filler. A single type of hydrophobic inorganic filler may be used, while two or more different types of hydrophobic inorganic fillers may be used in combination.

[0100] The term "inorganic filler" here should be understood as meaning a colorless or white, inorganic particle which is insoluble in a possible liquid component in the composition according to the present invention, whatever the temperature at which the composition is manufactured.

[0101] The inorganic filler may comprise metal oxides, preferably silica, titanium oxide, zinc oxide and a mixture thereof.

[0102] The inorganic filler that is suitable for the present invention may be, for example, a filler whose mean particle size is less than 100 μm, and especially between 1 and 50 μm, for example, between 4 to 20 μm. The term “hydrophobic” means that the inorganic filler can be individually dispersed in an oil in such a manner that aggregates are not formed.

[0103] The (c) hydrophobic inorganic filler may be porous or non-porous.

[0104] The (c) hydrophobic inorganic filler may be or may not be capable of absorbing (and / or adsorbing) an oil or a liquid fatty substance, for instance sebum (from the skin). It is preferable that the (c) hydrophobic inorganic filler be capable of absorbing (and / or adsorbing) an oil or a liquid fatty substance, for instance sebum (from the skin).

[0105] The (c) hydrophobic inorganic filler may have an oil-absorbing capacity of 100 ml / 100 g or more, preferably 150 ml / 100 g or more, and more preferably 200 ml / 100 g or more.

[0106] The amount of oil absorbed (and / or adsorbed) by the (c) hydrophobic inorganic filler may be determined as follows.

[0107] The amount of the absorbed (and / or adsorbed) oil can be measured according to the method for determining the oil uptake of a powder described in standard NF T 30-022. It corresponds to the amount of oil absorbed / adsorbed onto the available surface of the powder, by measuring the wet point Wp, corresponding to the amount of oil that needs to be added to 100 g of a powder in order to obtain a homogeneous paste

[0108] An amount of m = 2 g of powder is placed on a glass plate, and an oil (such as ester oil and silicone oil) is then added drop-wise. After addition of 4 to 5 drops of oil to the powder, mixing is performed using a spatula, and addition of oil is continued until a conglomerate of oil and powder has formed. At this point, the oil is added one drop at a time and the mixture is then triturated with the spatula. The addition of oil is stopped when a firm, smooth paste is obtained. This paste must be able to be spread on the glass plate without cracking or forming lumps. The volume Vs (expressed in ml) of oil used is then noted. The oil uptake corresponds to the ratio Vs / m.

[0109] Otherwise, the oil-absorbing capacity can be measured, in accordance with JIS-K6217-4.

[0110] The (c) hydrophobic inorganic filler may have at least one inorganic core and at least one hydrophobic coating.

[0111] The inorganic core may comprise at least one material selected from the group consisting of silica, silicate, perlite, boron nitride, magnesium carbonate, magnesium hydroxide, titanium oxide, zinc oxide, kaolin, talc, and a mixture thereof.

[0112] The hydrophobic coating may be formed by a hydrophobic treatment agent which may be chosen especially from fatty acids such as stearic acid; metal soaps such as aluminium dimyristate, the aluminium salt of hydrogenated tallow glutamate; amino acids; N-acylamino acids or salts thereof; lecithin, isopropyl triisostearyl titanate, mineral waxes, and mixtures thereof.

[0113] The N-acylamino acids may comprise an acyl group containing from 8 to 22 carbon atoms, for instance a 2-ethylhexanoyl, caproyl, lauroyl, myristoyl, palmitoyl, stearoyl, or cocoyl group. The salts of these compounds may be aluminium, magnesium, calcium, zirconium, zinc, sodium, or potassium salts. The amino acid may be, for example, lysine, glutamic acid, or alanine. The term "alkyl" mentioned in the compounds mentioned previously especially denotes an alkyl group containing from 1 to 30 carbon atoms and preferably containing from 5 to 16 carbon atoms.

[0114] Preferably, the (c) hydrophobic inorganic filler is selected from hydrophobically-modified metal oxides, and more preferably from hydrophobically-modified silica, titanium oxide, zinc oxide and a mixture thereof. The hydrophobically-modified metal oxides may have at least one hydrophobic coating on a particle of metal oxide.

[0115] Preferably, the (c) hydrophobic inorganic filler may be selected from hydrophobic silicas, in particular silica silylates.

[0116] The term "hydrophobic silica" is understood to mean any silica particle, the surface of which is treated to be hydrophobic. A hydrophobic silica or hydrophobic silica particle may have at least one hydrophobic coating on a particle of silica.

[0117] It is preferable that the (c) hydrophobic inorganic filler be selected from hydrophobic silica aerogel particles, and more preferably hydrophobic aerogels of silica silylate.

[0118] The hydrophobic silica, in particular silica silylate, may be based on silica aerogels which are porous materials obtained by replacing (by drying) the liquid component of a silica gel with air.

[0119] They are generally synthesized via a sol-gel process in a liquid medium and then dried, usually by extraction with a supercritical fluid, the one most commonly used being supercritical CO2. This type of drying makes it possible to avoid shrinkage of the pores and of the material. The sol-gel process and the various drying operations are described in detail in Brinker C.J. and Scherer G.W., Sol-Gel Science, New York, Academic Press, 1990.

[0120] Aerogels are materials with high porosity. Herein, silica aerogels refer to a solid silica with a porous structure generally obtained by replacing medium included in wet silica gels with air by drying them while a solid network structure of the silica is maintained. The porosity represents the amount of air contained in an apparent volume of a material by a volume percentage. The hydrophobic silica aerogel of the present invention may have a porosity of 60% or more, preferably 70% or more, and more preferably 80% or more.

[0121] The hydrophobic silica aerogel particles may exhibit a specific surface area per unit of weight (SW) ranging from 500 to 1,500 m2 / g, preferably from 600 to 1,200 m2 / g, and more preferably from 600 to 800 m2 / g, and / or a size, expressed as the volume-average diameter (D[0.5]), ranging from 1 to 1,500 μm, preferably from 1 to 1,000 μm, more preferably from 1 to 100 μm, particularly from 1 to 30 μm, even more preferably from 5 to 25 μm, further more preferably from 5 to 20 μm, and even further more preferably from 5 to 15 μm.

[0122] The specific surface area per unit of weight can be determined by the nitrogen absorption method, known as the BET (Brunauer-Emmett-Teller) method, described in The Journal of the American Chemical Society, Vol. 60, page 309, February 1938, which corresponds to international standard ISO 5794 / 1 (appendix D). The BET specific surface area corresponds to the total specific surface area of the particles under consideration.

[0123] The sizes of the hydrophobic silica aerogel particles can be measured by static light scattering using a commercial particle size analyzer of MasterSizer 2000 type from Malvern. The data are processed on the basis of the Mie scattering theory. This theory, which is exact for isotropic particles, makes it possible to determine, in the case of non-spherical particles, an "effective" particle diameter. This theory is described in particular in the publication by Van de Hulst, H.C., "Light Scattering by Small Particles", Chapters 9 and 10, Wiley, New York, 1957.

[0124] The hydrophobic silica aerogel particles can advantageously exhibit a packed density (r) ranging from 0.04 g / cm3to 0.10 g / cm3, and preferably from 0.05 g / cm3to 0.08 g / cm3.

[0125] In the context of the present invention, this density, known as the packed density, can be assessed according to the following protocol:

[0126] 40 g of powder are poured into a graduated measuring cylinder; the measuring cylinder is then placed on the Stav 2003 device from Stampf Volumeter; the measuring cylinder is subsequently subjected to a series of 2500 packing actions (this operation is repeated until the difference in volume between 2 consecutive tests is less than 2%); and the final volume Vf of packed powder is then measured directly on the measuring cylinder. The packed density is determined by the ratio w / Vf, in this instance 40 / Vf (Vf being expressed in cm3and w in g).

[0127] Regarding the preparation of hydrophobic silica aerogel particles modified at the surface by silylation, reference may be made to the document US 7470 725.

[0128] Use will in particular be made of hydrophobic silica aerogel particles modified at the surface with trimethylsilyl groups.

[0129] The (c) hydrophobic inorganic fillers that may be mentioned include polydimethylsiloxane-coated amorphous silica microspheres, especially those sold under the name Sunsphere® H33 and Sunsphere® H53 (oil uptake equal to 400 ml / 100 g), precipitated silica powders surface-treated with a mineral wax, such as precipitated silica treated with a polyethylene wax, and especially those sold under the name Acematt OR 412 by the company Evonik-Degussa (oil uptake equal to 398 ml / 100 g), and silica silylate sold under the name of VM-2270 (oil uptake equal to 1,040 ml / 100 g) by the company Dow.

[0130] It is preferable to use, as the (c) hydrophobic inorganic filler, silica silylate sold under the name VM-2270 by Dow, the particles of which exhibit an average size ranging from 5 to 15 μm and a specific surface area per unit of weight ranging from 600 to 800 m2 / g.

[0131] The hydrophobic silica aerogel particles may be characterized in that the shape of each of the particles is spherical. Due to this spherical shape, the hydrophobic silica aerogel particles can provide cosmetic compositions with good smoothness. The spherical degree of the hydrophobic silica aerogel may be determined by an average circularity.

[0132] The spherical hydrophobic silica aerogel particle may have an average circularity of 0.8 or more, and preferably 0.82 or more. The spherical hydrophobic silica aerogel may have an average circularity of less than 1, preferably 0.99 or less, more preferably 0.98 or less, even more preferably 0.97 or less, still even more preferably 0.96 or less, and most preferably 0.95 or less.

[0133] The "average circularity" may be determined by an image analysis method. In particular, the "average circularity" may be an arithmetic mean of circularity obtained by image analysis of a scanning electron microscope (SEM) image of no less than 2,000 aerogel particles observed at a magnification of 1,000 by secondary electron detection using a scanning electron microscope (SEM).

[0134] The "circularity" of each aerogel particle is a value determined by the following formula:

[0135] C = 4πS / L2wherein C represents circularity, S represents the area (projected area) of the aerogel particle in the image, and L represents the length of a periphery (perimeter) of the aerogel particle in the image. When the average circularity approaches 1 , the shape of each of the particles becomes more spherical.

[0136] The hydrophobic silica aerogel particles that may be used as the (c) hydrophobic inorganic filler according to the present invention is preferably of silylated silica type (INCI name: silica silylate). Preferably, the hydrophobic silica aerogel particles may be those described in JP-A-2014-088307, JP-A-2014-218433, or JP-A-2018-177620.

[0137] It is preferable to use hydrophobic aerogels of silica silylate as the inorganic hydrophobic oilabsorbing powder.

[0138] The hydrophobicity of the hydrophobic aerogels of silica silylate may be obtained by reacting a hydrophobicizing agent with a silanol group represented by the following formula existing on the surface of silica: ≡Si-OH wherein the symbol "≡" represents the remaining three valences of the Si atom, thereby converting the silanol group into a group represented by the following formula:

[0139] (≡Si-O-)(4-n)SiRnwherein n is an integer of 1 to 3; each R is independently a hydrocarbyl group; and two or more R may be the same or different from each other where n is 2 or more.

[0140] The hydrophobicizing agent may be a silylating agent. Therefore, according to one preferred embodiment, in the hydrophobic aerogels of silica silylate, the silica particles may be modified at the surface by silylation. As examples of the silylating agents, mention may be made of a treating agent having one of the following formulae (1) to (3).

[0141] Formula (1): RnSlX(4-n)wherein n represents an integer of 1 to 3; R represents a hydrocarbyl group; X represents a group (i.e. a leaving group) which can leave a molecule by cleavage of the bond with the Si atom in a reaction with a compound having a hydroxyl group; each R may be different where n is 2 or more; and each X may be different where n is 2 or less.

[0142] Formula (2): wherein R1represents an alkylene group; R2and R3independently represent a hydrocarbyl group; and R4and R5independently represent a hydrogen atom or a hydrocarbyl group.

[0143] Formula (3): wherein R6and R7independently represent a hydrocarbyl group; m represents an integer of 3 to 6; each R6may be different when there are two or more R6; and each R7may be different when there are two or more R7.

[0144] In the above formula (1), R is a hydrocarbyl group, preferably a hydrocarbyl group having a carbon number of 1 to 10, more preferably a hydrocarbyl group having a carbon number of 1 to 4, and especially preferably a methyl group.

[0145] As examples of the leaving group represented by X, mention may be made of halogen atoms such as chlorine and bromine; alkoxy groups such as methoxy group and ethoxy group; groups represented by -NH-SiR3(wherein the definition of R is the same as that of R in formula (1)).

[0146] Specific examples of the hydrophobicizing agent represented by the above formula (1) include: chlorotrimethylsilane, dichlorodimethylsilane, trichloromethylsilane, monomethyltrimethoxysilane, monomethyltriethoxysilane, and hexamethyldisilazane.

[0147] Most preferably, chlorotrimethylsilane, dichlorodimethylsilane, trichloromethylsilane, and / or hexamethyldisilazane may be used from the viewpoint of favorable reactivity.

[0148] The number of bonds of the Si atom with the silanol group on the silica framework varies depending on the number (4-n) of the leaving group X. For example, if n is 2, the following bonding will occur:

[0149] (≡Si-O-)2SiR2.

[0150] If n is 3, the following bonding will occur: ≡Si-O-SiR3.

[0151] In this manner, the silanol groups may be silylated, and thereby hydrophobization may be earned out. In the above formula (2), R1may be an alkylene group, preferably an alkylene group having a carbon number of 2 to 8, and especially preferably an alkylene group having a carbon number of 2 to 3.

[0152] In the above formula (2), R2and R3are independently a hydrocarbyl group, and the same preferable groups as those of R in the formula (1 ) can be mentioned. R4represents a hydrogen atom or a hydrocarbyl group, and when it is a hydrocarbyl group, the same preferable groups as those of R in the formula (1 ) can be mentioned. When a gel of silica is treated with the compound (cyclic silazane) represented by formula (2), cleavage of Si-N bonds will occur by the reaction with silanol groups, and therefore the following bonding will occur on the surface of the silica framework in the gel:

[0153] (≡Si-O-)2SiR2R3

[0154] In this way, the silanol group may be silylated by the cyclic silazanes of the above formula (2) as well, and thereby hydrophobization may be carried out.

[0155] Specific examples of the cyclic silazanes represented by the above formula (3) include hexamethylcyclotrisilazane, and octamethylcyclotetrasilazane.

[0156] In the above formula (3), R6and R7are independently a hydrocarbyl group, and the same preferable groups as those of R in the formula (2) can be mentioned, m represents an integer of 3 to 6. When a gel of silica is treated with the compound (cyclic siloxane) represented by the formula (3), the following bonding will occur on the surface of the silica framework in the gel:

[0157] (≡Si-O-)2SiR6R7

[0158] In this way, silanol groups may be silylated by the cyclic siloxanes of the above formula (3) as well, and thereby hydrophobization may be carried out.

[0159] Specific examples of the cyclic siloxanes represented by the above formula (3) include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and decamethylcyclopentasiloxane.

[0160] The hydrophobic aerogels of silica silylate may be prepared by producing a sol of silica, turning the sol into a gel, aging the gel, washing the aged gel, replacing water in the washed gel with a solvent, treating the gel with a hydrophobicizing agent, and dying the hydrophobicized silica.

[0161] The hydrophobic aerogels of silica silylate may have a specific surface area determined by BET method of 200 m2 / g or more, preferably 400 m2 / g or more, and more preferably 500 m2 / g or more, and may have a specific surface area determined by BET method of 1,200 m2 / g or less, preferably 1 ,000 m2 / g or less, and more preferably 800 m2 / g or less.

[0162] The hydrophobic aerogels of silica silylate may have a pore volume determined by BJH method of 1 ml / g or more, preferably 2 ml / g or more, and more preferably 3 ml / g or more, and may have a pore volume determined by BJH method of 10 ml / g or less, preferably 8 ml / g or less, and more preferably 7 ml / g or less. The hydrophobic silica aerogel of silica silylate may have a peak pore radius determined by BJH method of 5 nm or more, preferably 10 run or more, and more preferably 12 nm or more, and may have a peak pore radius determined by BJH method of 50 nm or less, preferably 40 nm or less, and more preferably 30 nm or less. The "pore volume determined by BJH method" refers to a pore volume which derives from a pore having a pore radius of 1 nm to 100 nm obtained by analyzing, by the BJH method (Barrett, E. P.; Joyner, L. G.; Halenda, P. P., J. Am. Chem. Soc. 73, 373 (1951)), the adsorption isotherm of the nitrogen adsorption side obtained in the same manner as explained in the above "specific surface area determined by BET method". The "peak pore radius determined by BJT method" refers to a value of a pore radius which gives a peak in a pore distribution curve (volume distribution curve) which is plotted taking on the vertical axis differentiation of the cumulative pore volume by the logarithm of the pore radius obtained by analyzing, by the BJH method, the adsorption isotherm of the nitrogen adsorption side obtained in the same manner as above, and taking the pore radius on the horizontal axis.

[0163] The hydrophobic aerogels of silica silylate may have an average particle size of 0.5 μm or more, preferably 1 μm or more, and more preferably 2 μm or more, and may have an average particle size by image analysis method of 30 μm or less, preferably 20 μm or less, and more preferably 15 μm or less.

[0164] The "average particle size” here can be measured by an image analysis method. Specifically, the value of "average particle size” is an arithmetic mean of equivalent circle diameters which can be obtained by image analysis of a scanning electron microscope (SEM) image of, for example, no less than 2,000 aerogel particles observed at a magnification of 1,000 by secondary electron detection using a scanning electron microscope (SEM). The "equivalent circle diameter" of each aerogel particle is the diameter of a circle having an area equal to the area (projected area) of the aerogel particle in the image.

[0165] Preferably, the hydrophobic aerogels of silica silylate may have an oil-absorbing capacity, which can be measured at the wet point, as explained above, of 2 ml / g or more, preferably 3 ml / g or more, more preferably 4 ml / g or more, and most preferably from 5 ml / g or more, and may have an oil-absorbing capacity, measured at the wet point, of 12 ml / g or less, preferably 10 ml / g or less, more preferably 8 ml / g or less, and most preferably 7 ml / g or less.

[0166] It is preferable that the (c) hydrophobic inorganic filler be selected from hydrophobically-modified metal oxides, more preferably selected from hydrophobic silicas, and even more preferably silica silylates.

[0167] The amount of the (c) hydrophobic inorganic filler(s) in the composition according to the present invention may be 0.01% by weight or more, preferably 0.05% by weight or more, and more preferably 0.1% by weight or more, relative to the total weight of the composition.

[0168] On the other hand, the amount of the (c) hydrophobic inorganic filler(s) in the composition according to the present invention may be 3% by weight or less, preferably 1 % by weight or less, and more preferably 0.5% by weight or less, relative to the total weight of the composition.

[0169] Thus, the amount of the (c) hydrophobic inorganic filler(s) in the composition according to the present invention may range from 0.01% to 3% by weight, preferably from 0.05% to 1% by weight, and more preferably from 0.1% to 0.5% by weight, relative to the total weight of the composition.

[0170] (Hyaluronic Acid Ingredient) The composition according to the present invention may comprise (d) at least one hyaluronic acid ingredient selected from the group consisting of hyaluronic acid, hyaluronic acid salts, hyaluronic acid derivatives, hyaluronic acid derivative salts, and mixtures thereof. A single type of hyaluronic acid ingredient may be used, but two or more different types of hyaluronic acid ingredients may be used in combination.

[0171] Hyaluronic acid is a predominant glucosaminoglycan found in the skin. Thus, the fibroblasts synthesize predominantly collagens, matrix glycoproteins other than collagens (fibronectin, laminin), proteoglycans and elastin. The keratinocytes, for their part, synthesize predominantly sulfated glycosaminoglycans and hyaluronic acid. Hyaluronic acid is also called hyaluronan.

[0172] Hyaluronic acid is present in the free state in the epidermis and in the dermis and is responsible for turgescence of the skin. This polysaccharide can in fact retain a large volume of water, corresponding to up to 1000 times its weight. In this sense, hyaluronic acid plays an important role in increasing the amounts of water bound in the tissue, and also in the mechanical properties of the skin and in wrinkle formation.

[0173] Hyaluronic acid can be represented by the following chemical formula.

[0174] In the context of the present invention, the term "hyaluronic acid" covers in particular the basic unit of hyaluronic acid of formula:

[0175] It is the smallest fraction of hyaluronic acid comprising a disaccharide dimer, namely D- glucuronic acid and N-acetylglucosamine.

[0176] The term "hyaluronic acid" comprises, in the context of the present invention, the linear polymer comprising the polymeric unit described above, linked together in the chain via alternating β(1,4) and β(1,3) glycosidic linkages, having a molecular weight (Mw) that may range between 380 and 13 000 000 daltons. This molecular weight depends in large part on the source from which the hyaluronic acid is obtained and / or on the preparation methods.

[0177] The term “hyaluronic acid” also comprises, in the context of the present invention, hydrolysed hyaluronic acid. The term "hyaluronic acid derivatives" comprises, in the context of the present invention, hyaluronic acid esters in particular those in which all or some of the carboxylic groups of the acid functions are esterified with oxyethylenated alkyls or alcohols, containing from 1 to 20 carbon atoms, in particular with a degree of substitution at the level of the D-glucuronic acid of the hyaluronic acid ranging from 0.5% to 50%.

[0178] Mention may in particular be made of methyl, ethyl, n-propyl, n-pentyl, benzyl and dodecyl esters of hyaluronic acid. Such esters have in particular been described in D. Campoccia et al. "Semisynthetic resorbable materials from hyaluronan esterification", Biomaterials 19 (1998) 2101-2127.

[0179] In one embodiment, the hyaluronic acid derivative may be, for example, acetylated hyaluronic acid.

[0180] The term “hyaluronic acid derivatives” also comprises, in the context of the present invention, cationic hyaluronic acids.

[0181] The cationic hyaluronic acid comprises at least one cationic moiety. The cationic moiety may be a trialkyl ammonium group such as -N+(CH3)3. The cationic moiety may include at least one hydroxyl group. The examples of the cationic group include -CH2-CH(OH)-CH2-N+(CH3)3.

[0182] Examples of the cationic hyaluronic acid includes hydroxypropyl trimonium hyaluronate.

[0183] As hyaluronic acid salts or hyaluronic acid derivative salts, mention may be made of alkaline metal salts such as sodium salt and potassium salt, alkaline earth metal salts such as magnesium salts, ammonium salts, and mixtures thereof.

[0184] The molecular weight of the (d) hyaluronic acid ingredient is not limited. The molecular weight of the (d) hyaluronic acid ingredient may be 5 kDa or more, preferably 20 kDa or more, and more preferably 100 kDa or more. The molecular weight of the (d) hyaluronic acid ingredient may be 20 MDa or less, preferably 10 MDa or less, and more preferably 2,000 kDa or less. Thus, the molecular weight of the (d) hyaluronic acid ingredient may be from 5 kDa to 20 MDa, preferably from 20 kDa to 10 MDa, and more preferably from 100 kDa to 2,000 kDa.

[0185] Unless otherwise defined in the descriptions, “molecular weight” may mean a weight average molecular weight.

[0186] The (d) hyaluronic acid ingredient may in particular be hyaluronic acid supplied by the company Centipro under the trade name Hy Active™ (Mw: 10 to 150 kDa), by the company Givaudan under the trade name Cristalhyal® (Mw: 1 to 1.4 MDa), by the company Bioland under the trade name Nutra™ HA (Mw: 907,600 Da), by the company Bioland under the trade name Nutra™ HAF (Mw: 74,600 Da), by the company Bioland under the trade name Oligo™ HA (Mw: 0.5 to 10.1 kDa), by the company Res Pharma under the trade name D-Factor® (Mw: 380 Da), or by the company Bloomage Freda Biopharm under the trade name Hybloom™ Sodium Hyaluronate (HA-T) (MW: 1,000 kDa to 1,800 kDa)..

[0187] A single hyaluronic acid ingredient with a single molecular weight, or a combination of two or more hyaluronic acid ingredients with different molecular weights may be used as the (d) hyaluronic acid ingredient. It is preferable that the (d) hyaluronic acid ingredient be hyaluronic acid salts, and more preferably hyaluronic acid alkaline metal salts, such as sodium hyaluronate.

[0188] The amount of the (d) hyaluronic acid ingredient(s) in the composition according to the present invention may be 0.001% by weight or more, preferably 0.005% by weight or more, and more preferably 0.01% by weight or more, relative to the total weight of the composition.

[0189] The amount of the (d) hyaluronic acid ingredient(s) in the composition according to the present invention may be 3% by weight or less, preferably 1% by weight or less, and more preferably 0.5% by weight or less, relative to the total weight of the composition.

[0190] Thus, the amount of the (d) hyaluronic acid ingredient(s) in the composition according to the present invention may range from 0.001% to 3% by weight, preferably from 0.005% to 1% by weight, and more preferably from 0.01% to 0.5% by weight, relative to the total weight of the composition.

[0191] (Polysaccharide)

[0192] The composition according to the present invention may comprise (e) at least one polysaccharide. If two or more polysaccharides are used, they may be the same or different.

[0193] The (e) polysaccharide can be present in the aqueous phase in the composition according to the present invention, if the composition according to the present invention comprises water. The (e) polysaccharide can function as a hydrophilic thickener which can thicken the aqueous phase of the composition according to the present invention.

[0194] It is preferable that the (e) polysaccharide be derived from micoorganisms or plants.

[0195] The (e) polysaccharide derived from microorganisms means a polysaccharide produced by microorganisms such as germs or bacteria.

[0196] As examples of the (e) polysaccharide derived from microorganisms, mention may be made of cardollan, xanthan gum, Jellan gum, dextran, pullulan, sclerotium gum, and mixtures thereof.

[0197] It may be preferable that the (e) polysaccharide derived from microorganisms be selected from the group consisting of sclerotium gum, xanthan gum and mixtures thereof. Fermented polysaccharides such as Biosaccharide Gum- 1, Biosaccharide Gum-2 and Biosaccharide-4 may also be used.

[0198] On the other hand, the (e) polysaccharide derived from plants means a polysaccharide obtained from plants or algae.

[0199] As examples of the (e) polysaccharide derived from plants that may be used according to the present invention, mention may be made especially of: a) algal extracts, such as alginates, carrageenans and agars, and mixtures thereof. Examples of carrageenans that may be mentioned include Satiagum UTC30® and UTC10® from the company Degussa; an alginate that may be mentioned is the sodium alginate sold under the name Kelcosol® by the company ISP; b) gums, such as guar gum and nonionic derivatives thereof (hydroxypropyl guar), gum arabic, konjac gum or mannan gum, gum tragacanth, ghatti gum, karaya gum or locust bean gum; examples that may be mentioned include the guar gum sold under the name Jaguar HP105® by the company Rhodia; the mannan and konjac gum® (1% gluconomannan) sold by the company GfN; c) modified or unmodified starches, such as those obtained, for example, from cereals, for instance wheat, com or rice, from legumes, for instance blonde peas, from tubers, for instance potato or cassava, and tapioca starches; dextrins, such as com dextrins; examples that may especially be mentioned include the rice starch Remy DR I® sold by the company Remy; the com starch B® from the company Roquette; the potato starch modified with 2-chloroethylaminodipropionic acid neutralized with sodium hydroxide, sold under the name Structure Solanace® by the company National Starch; the native tapioca starch powder sold under the name Tapioca pure® by the company National Starch; d) dextrins, such as the dextrin extracted from com under the name Index® from the company National Starch; e) celluloses and derivatives thereof, particularly alkyl celluloses, hydroxyalkyl celluloses; and alkyl hydroxyalkyl celluloses; mention may be made especially of methyl-celluloses, hydroxyethylcelluloses, ethyl-hydroxyethylcelluloses and carboxymethyl-celluloses. Examples that may be mentioned include stearyl and cetyl hydroxyethylcellulose. Examples of cetyl hydroxyethylcelluloses that may be mentioned include Polysurf 67CS® and Natrosol Plus 330® from Aquaion; and mixtures thereof.

[0200] Preferably, the (e) polysaccharide derived from plants may be chosen from an algal extract, a gum and a cellulose derivative, and mixtures thereof. More preferably, agars, locust bean gum, mannan konjac gum, cetyl or stearyl hydroxyethylcelluloses and tapioca starches may be used.

[0201] The (e) polysaccharide derived from plants may be an algal extract chosen from alginates, carrageenans and agars, and mixtures thereof. Preferably, alginates or agars, or mixtures thereof, will be used.

[0202] The (e) polysaccharide derived from plants may also be chosen from a gum, such as guar gum, gum arabic, mannan and konjac gum and locust bean (carob) gum, and mixtures thereof.

[0203] The (e) polysaccharide derived from plants may also be a modified or unmodified starch chosen from wheat starch, com starch, rice starch, potato starch and tapioca starch, and mixtures thereof.

[0204] The (e) polysaccharide derived from plants may also be a dextrin, such as com dextrin.

[0205] The (e) polysaccharide derived from plants may also be a cellulose derivative. The cellulose derivative may particularly be a (C1-C3) hydroxyalkyl cellulose, especially modified with hydrophobic chains, particularly hydrophobic group(s) containing from 8 to 30 carbon atoms. According to one embodiment, the hydrophobic substituent(s) used may be C8-C30and preferably C10-C22alkyl, arylalkyl or alkylaryl groups. Preferably, the hydrophobic substituent(s) according to the present invention may be saturated C10-C22and preferably C16-C20alkyl chains, such as cetyl (C16), stearyl (C18) and behenyl (C20) groups. According to one preferred embodiment, the hydrophobic substituent(s) according to the present invention may be cetyl groups. These cellulose derivatives containing hydrophobic substituent(s) according to the present invention may have a viscosity preferably of between 100 and 100 000 mPas and preferably between 200 and 20 000 mPas, measured at 25°C in a solution containing 1% by weight of a polymer in water, this viscosity being determined conventionally using a viscometer of Brookfield LVT type at 6 rpm with a No. 3 spindle. Among the cellulose derivatives containing hydrophobic substituent(s) that may be used in the compositions according to the present invention, mention may preferably be made of the cetyl hydroxy ethylcelluloses sold under the names Natrosol Plus Grade 330 CS and Polysurf 67 CS (INCI name: cetyl hydroxyethylcellulose) by the company Aqualon / Hercules.

[0206] Preferably, the (e) polysaccharide derived from plants is selected from non-cellulose polysaccharides.

[0207] Preferably, the (e) polysaccharide is selected from the group consisting of the polysaccharide derived from plants, the polysaccharide derived from microorganisms, and mixture thereof.

[0208] More preferably, the (e) polysaccharide is selected from the group consisting of an algal extract, a gum and a cellulose derivative, sclerotium gum, xanthan gum, fermented polysaccharides such as Biosaccharide Gum-1, Biosaccharide Gum-2 and Biosaccharide-4, and mixtures thereof.

[0209] Even more preferably, the (e) polysaccharide is selected from the group consisting of sclerotium gum, xanthan gum, fermented polysaccharides such as Biosaccharide Gum-1, Biosaccharide Gum-2 and Biosaccharide-4, and mixtures thereof.

[0210] The amount of (e) polysaccharide(s) in the composition according to the present invention may be 0.001% by weight or more, preferably 0.005% by weight or more, and more preferably 0.01% by weight or more, relative to the total weight of the composition.

[0211] On the other hand, the amount of (e) polysaccharide(s) in the composition according to the present invention may be 3% by weight or less, preferably 2% by weight or less, and more preferably 1% by weight or less, relative to the total weight of the composition.

[0212] The amount of (e) polysaccharide(s) in the composition according to the present invention may range from 0.001% to 3% by weight, preferably from 0.005% to 2% by weight, more preferably from 0.01% to 1% by weight, relative to the total weight of the composition.

[0213] (Water)

[0214] The composition according to the present invention may comprise water.

[0215] The amount of water in the composition according to the present invention may be 50% by weight or more, preferably 60% by weight or more, and more preferably 70% by weight or more, relative to the total weight of the composition.

[0216] On the other hand, the amount of water in the composition according to the present invention may be 95% by weight or less, preferably 90% by weight or less, and more preferably 85% by weight or less, relative to the total weight of the composition.

[0217] The amount of water in the composition according to the present invention may range from 50% to 95% by weight, preferably from 60% to 90% by weight, more preferably from 70% to 85% by weight, relative to the total weight of the composition.

[0218] (Polyol)

[0219] The composition according to the present invention may comprise at least one polyol. A single type of polyol may be used, but two or more different types of polyol may be used in combination. The term “polyol” here means an alcohol having two or more hydroxy groups, and does not encompass a saccharide or a derivative thereof. The derivative of a saccharide includes a sugar alcohol which is obtained by reducing one or more carbonyl groups of a saccharide, as well as a saccharide or a sugar alcohol in which the hydrogen atom or atoms in one or more hydroxy groups thereof has or have been replaced with at least one substituent such as an alkyl group, a hydroxyalkyl group, an alkoxy group, an acyl group or a carbonyl group.

[0220] The polyol may be a C2-C12polyol, preferably a C2-C9polyol, comprising at least 2 hydroxy groups, and preferably 2 to 5 hydroxy groups.

[0221] The polyol may be a natural or synthetic polyol. The polyol may have a linear, branched or cyclic molecular structure.

[0222] The polyol may be selected from glycerins and derivatives thereof, and glycols and derivatives thereof. Preferably, the polyol is selected from the group consisting of glycerin, diglycerin, polyglycerin, ethyleneglycol, diethyleneglycol, propyleneglycol, dipropyleneglycol, butyleneglycol, pentyleneglycol, hexyleneglycol, 1,3 -propanediol, 1,5-pentanediol, and polyethyleneglycol (5 to 50 ethyleneoxide groups).

[0223] The polyol may be present in an amount ranging from 0.01% to 25% by weight, and preferably from 0.1% to 20% by weight, such as from 1 % to 15% by weight, relative to the total weight of the composition according to the present invention.

[0224] (Other Optional Ingredients)

[0225] The composition according to the present invention may also comprise an effective amount of other optional ingredients, known previously elsewhere in cosmetic compositions, e.g., sequestering agents or chelating agents,; preserving agents and co-preserving agents,; vitamins or provitamins, fragrances; plant extracts; and so on.

[0226] The composition according to the present invention may further comprise at least one organic solvent. Thus, the organic solvent is preferably water miscible. As the organic solvent, there may be mentioned, for example, C1-C4alkanols, such as ethanol and isopropanol; aromatic alcohols such as benzyl alcohol and phenoxyethanol; analogous products; and mixtures thereof.

[0227] The organic water-soluble solvents may be present in an amount ranging from 0.01% by weight or more, preferably 0.1% by weight or more, and more preferably 1 % by weight or more, relative to the total weight of the composition according to the present invention.

[0228] The organic water-soluble solvents may be present in an amount ranging from 15% by weight or less, preferably 10% by weight or less, and more preferably 5% by weight or less, relative to the total weight of the composition according to the present invention.

[0229] The organic water-soluble solvents may be present in an amount ranging from 0.01% to 15% by weight, preferably from 0.1% to 10% by weight, and more preferably from 1% to 5% by weight, relative to the total weight of the composition according to the present invention.

[0230] The composition according to the present invention may include a limited amount of oil(s). The amount of oil(s) in the composition according to the present invention may be 10% by weight or less, preferably 5% by weight or less, and more preferably 1% by weight or less, relative to the total weight of the composition. It may be particularly preferable that the composition according to the present invention include no oil.

[0231] Preferably, the composition according to the present invention includes a very limited amount of silicone(s).

[0232] Preferably, the amount of silicone(s), such as organopolysiloxanes, in the composition according to the present invention is 1% by weight or less, preferably 0.1% by weight or less, and more preferably 0.01 % by weight or less, relative to the total weight of the composition. It is particularly preferable that the composition according to the present invention include no silicone.

[0233] According to a preferred embodiment, the composition according to the present invention comprises, relative to the total weight of the composition: from 0.001% to 3% by weight of polyglutamic acid or sodium polyglutamate, as the ingredient (a); from 0.01% to 5% by weight of crosslinked neutralized poly(meth)acrylic acid polymer, as the ingredient (b); and from 0.01% to 3% by weight of hydrophobic silica, as the ingredient (c).

[0234] According to a more preferred embodiment, the composition according to the present invention comprises, relative to the total weight of the composition: from 0.01% to 0.5% by weight of sodium polyglutamate, as the ingredient (a); from 0.1% to 3% by weight of sodium carbomer, as the ingredient (b); and from 0.1% to 0.5% by weight of silica silylate, as the ingredient (c).

[0235] (Preparation)

[0236] The composition according to the present invention can be prepared by mixing the essential ingredient(s) as explained above, and optional ingredient(s), if necessary, as explained above.

[0237] The method and means to mix the above essential and optional ingredients are not limited. Any conventional method and means can be used to mix the above essential and optional ingredients to prepare the composition according to the present invention. The conventional method and means include a homogenizer, for example, a turbine mixer.

[0238] (Form)

[0239] The composition according to the present invention may be in various forms.

[0240] The composition according to the present invention can be in the form of a fluid such as a viscous liquid at an ambient temperature (25°C) and under atmospheric pressure (760 mm Hg).

[0241] The composition according to the present invention may be in the form of an aqueous gel, if the composition comprises water, because the (b) neutralized poly(meth)acrylic acid polymer can function as a thickener.

[0242] The composition according to the present invention may be transparent or translucent. (pH)

[0243] The pH of the composition according to the present invention may be less than 7.0, preferably less than 6.5, and more preferably less than 6.0.

[0244] The pH of the composition according to the present invention may be 3.0 or more, preferably 3.5 or more, and more preferably 4.0 or more.

[0245] For example, the pH of the composition according to the present invention may be from 3.0 to less than 7.0, preferably from 3.5 to less than 6.5, and more preferably from 4.0 to less than 6.0.

[0246] The pH of the composition according to the present invention may be adjusted by adding at least one alkaline agent and / or at least one acid or a salt thereof. The pH of the composition according to the present invention may also be adjusted by adding at least one buffering agent.

[0247] [Process and Use]

[0248] It is preferable that the composition according to the present invention be a cosmetic composition, and more preferably a cosmetic composition for a keratin substance such as skin.

[0249] The composition according to the present invention is suitable as a skin care cosmetic composition. For example, the composition according to the present invention can be used for moisturizing the skin.

[0250] It is preferable that the composition according to the present invention be a leave-on type. In other words, it is preferable that the composition according to the present invention be used, on a keratin substance such as skin, without being rinsing off. Thus, it is preferable that the composition according to the present invention is not a cleansing composition.

[0251] The present invention also relates to a cosmetic process for a keratin substance such as skin, comprising: applying to the keratin substance the composition according to the present invention.

[0252] The cosmetic process here means a non-therapeutic beautifying method for caring for and / or making up the surface of a keratin substance such as skin, preferably a non-therapeutic beautifying method for caring for the skin.

[0253] It is preferable that the cosmetic process according to the present invention is not a cleansing process. Thus, it is preferable that the cosmetic process according to the present invention does not include a step of rinsing off the composition according to the present invention from the keratin substance such as skin.

[0254] The present invention may also relate to a use of (a) at least one polyglutamic acid or a salt thereof in a composition comprising:

[0255] (b) at least one neutralized poly(meth)acrylic acid polymer; and

[0256] (c) at least one hydrophobic inorganic filler, in order to improve any one of the spreadability, smoothness after application, and moisturizing feeling, of the composition, and / or reduce the formation of noodles from the composition.

[0257] The present invention may also relate to a use of (b) at least one neutralized poly(meth)acrylic acid polymer in a composition comprising: (a) at least one polyglutamic acid or a salt thereof; and

[0258] (c) at least one hydrophobic inorganic filler, in order to stabilize the composition, or in order to improve any one of the spreadability, smoothness after application, and moisturizing feeling, of the composition.

[0259] The present invention may also relate to a use of (c) at least one hydrophobic inorganic filler in a composition comprising:

[0260] (a) at least one polyglutamic acid or a salt thereof; and

[0261] (b) at least one neutralized poly(meth)acrylic acid polymer, in order to improve any one of the spreadability and smoothness after application, of the composition, and / or reduce the formation of noodles from the composition.

[0262] The above explanations regarding the (a) polyglutamic acid or a salt thereof, the (b) neutralized poly(meth)acrylic acid polymer, and the (c) hydrophobic inorganic filler for the composition according to the present invention, can apply to those in the above use.

[0263] EXAMPLES

[0264] The present invention will be described in more detail by way of examples, which however should not be construed as limiting the scope of the present invention.

[0265] [Examples 1-2 and Comparative Examples 1-4]

[0266] The following compositions according to Examples 1 -2 and Comparative Examples 1 -4, shown in Table 1 , were prepared by mixing the components shown in Table 1. The numerical values for the amounts of the components shown in Table 1 are all based on “% by weight” as raw materials. The symbols (a)-(e) in Table 1 correspond to the ingredients (a)-(e) in the claims.

[0267]

[0268] NA: Not Available

[0269] [Evaluations]

[0270] (Thermal Stability)

[0271] Each of the compositions according to Examples 1-2 and Comparative Examples 1-4 was filled into a glass bottle and was held at a temperature of 55 °C for 1 week. Each composition was then investigated with regard to the change in aspect of the composition, and evaluated in accordance with the following criteria:

[0272] Good: Uniform gel was observed.

[0273] Poor: Sedimentation of silica was observed.

[0274] The results are shown in Table 1.

[0275] (Spreadability)

[0276] Six professional panelists evaluated the “spreadability” during the application of the compositions according to Examples 1-2 and Comparative Examples 1-4. Each panelist took each composition in their hands, then applied it onto their faces to evaluate easiness to spread with less friction feeling, and graded it from 1 (poor) to 5 (very good), which was then classified in the following two categories based on the average of the grade:

[0277] Good: From 5.0 to 4.0

[0278] Poor: From 3.9 to 0

[0279] The results are shown in Table 1.

[0280] (Moisturizing Feeling)

[0281] Six professional panelists evaluated the “moisturizing feeling” after the application of the compositions according to Examples 1-2 and Comparative Examples 1-4. Each panelist took each composition in their hands, then applied it onto their faces to evaluate moisturizing feeling such that the inner of the skin was moisturized, after the application, and graded it from 1 (poor) to 5 (very good), which was then classified in the following three categories based on the average of the grade:

[0282] Good: From 5.0 to 3.5

[0283] Fair: From 3.4 to 2.5 Poor: From 2.4 to 0

[0284] The results are shown in Table 1.

[0285] (Smoothness After Application)

[0286] Six professional panelists evaluated the “smoothness after application" of the compositions according to Examples 1-2 and Comparative Examples 1-4. Each panelist took each composition in their hands, then applied it onto their faces to evaluate smoothness after application, and graded it from 1 (poor) to 5 (very good), which was then classified in the following 3 categories based on the average of the grade:

[0287] Good: From 5.0 to 3.5

[0288] Fair: From 3.4 to 2.5

[0289] Poor: From 2.4 to 0

[0290] The results are shown in Table 1.

[0291] (Formation of Noodles)

[0292] Six professional panelists evaluated the “formation of noodles” after application of the compositions according to Examples 1-2 and Comparative Examples 1-4. Each panelist took each composition in their hands, then applied it onto their faces to evaluate the formation of noodles after application. The evaluations were classified in accordance with the following 2 categories:

[0293] Good: 0 or 1 member answered that noodles were or would be generated.

[0294] Poor: 2 to 6 members answered that noodles were generated or would be generated.

[0295] The results are shown in Table 1.

[0296] (Summary)

[0297] The compositions according to Examples 1-2 were stable and showed good spreadability during application and smoothness after application.

[0298] The compositions according to Examples 1-2 were also able to provide good moisturizing feeling and suppress the formation of noodles.

[0299] The comparison between Example 1 and Example 2 demonstrates that the use of more amount of the ingredient (b) can further improve smoothness after application.

[0300] Comparative Example 1 shows that no use of the ingredient (a) caused poor spreadability during application, poor smoothness after application, poor moisturizing feeling, and formation of noodles.

[0301] Comparative Example 2 shows that no use of the ingredient (b) caused instability. In fact, the composition according to Comparative Example 2 caused sedimentation of the ingredient (c), and therefore, the sensory evaluation was not possible.

[0302] Comparative Example 3 shows that no use of the ingredient (c) caused poor spreadability, poor smoothness after application, and formation of noodles.

[0303] Comparative Example 4 shows that use of non-neutralized poly(meth)acrylic acid polymer instead of the ingredient (b) caused poor spreadability, poor smoothness after application, and a poor moisturizing feeling.

Claims

CLAIMS1. A composition, preferably a cosmetic composition, and more preferably a skin cosmetic composition, comprising:(a) at least one polyglutamic acid or a salt thereof;(b) at least one neutralized poly(meth)acrylic acid polymer; and(c) at least one hydrophobic inorganic filler.

2. The composition according to Claim 1 , wherein the amount of the (a) polyglutamic acid(s) or salt(s) thereof in the composition ranges from 0.001% to 3% by weight, preferably from 0.005% to 1% by weight, and more preferably from 0.01% to 0.5% by weight, relative to the total weight of the composition.

3. The composition according to Claim 1 or 2, wherein the (b) neutralized poly(meth)acrylic acid polymer is totally or partially neutralized, and preferably partially neutralized.

4. The composition according to any one of Claims 1 to 3, wherein the (b) neutralized poly(meth)acrylic acid polymer is totally or partially in the form of a salt, preferably a metal salt, more preferably an alkaline metal salt, and even more preferably a sodium salt.

5. The composition according to any one of Claims 1 to 4, wherein the (b) neutralized poly(meth)acrylic acid polymer has a repeating unit represented by the following formula (I): -[CH(R1)-C(R2)(COO-M+)]- (I) whereinR1and R2, identical or different, represent a hydrogen atom or a (C1-C6)alkyl group such as methyl, preferably R1and R2represent a hydrogen atom; andM+represents H+or a cationic counterion, preferably an alkali metal cation, alkaline earth metal cation or ammonium ion, more preferably M+represents an alkali metal cation such as sodium cation.

6. The composition according to any one of Claims 1 to 5, wherein the (b) neutralized poly(meth)acrylic acid polymer is a crosslinked homopolymer.

7. The composition according to any one of Claims 1 to 6, wherein the amount of the (b) neutralized poly(meth)acrylic acid polymer(s) in the composition ranges from 0.01% to 5% by weight, preferably from 0.05% to 4% by weight, and more preferably from 0.1% to 3% by weight, relative to the total weight of the composition.

8. The composition according to any one of Claims 1 to 7, wherein the (c) hydrophobic inorganic filler is selected from hydrophobically-modified metal oxides, and preferably from hydrophobically-modified silica, titanium oxide, zinc oxide, and a mixture thereof.

9. The composition according to any one of Claims 1 to 8, wherein the (c) hydrophobic inorganic filler is selected from hydrophobic silicas, preferably from hydrophobic silica aerogel particles, and more preferably from hydrophobic aerogel particles of silica silylate.

10. The composition according to any one of Claims 1 to 9, wherein the amount of the (c) hydrophobic inorganic filler(s) in the composition ranges from 0.01% to 3% by weight,preferably from 0.05% to 1% by weight, and more preferably from 0.1% to 0.5% by weight, relative to the total weight of the composition.

11. The composition according to any one of Claims 1 to 10, wherein the composition further comprises (d) at least one hyaluronic acid ingredient selected from the group consisting of hyaluronic acid, hyaluronic acid salts, hyaluronic acid derivatives, hyaluronic acid derivative salts, and mixtures thereof.

12. The composition according to Claim 11 , wherein the amount of the (d) hyaluronic acid ingredient(s) in the composition ranges from 0.001% to 3% by weight, preferably from 0.005% to 1% by weight, and more preferably from 0.01% to 0.5% by weight, relative to the total weight of the composition.

13. The composition according to any one of Claims 1 to 12, wherein the composition further comprises (e) at least one polysaccharide, preferably the (e) polysaccharide is selected from the group consisting of an algal extract, a gum and a cellulose derivative, sclerotium gum, xanthan gum, fermented polysaccharides such as Biosaccharide Gum-1, Biosaccharide Gum-2 and Biosaccharide-4, and mixtures thereof, and more preferably the (e) polysaccharide is selected from the group consisting of sclerotium gum, xanthan gum, fermented polysaccharides such as Biosaccharide Gum-1, Biosaccharide Gum-2 and Biosaccharide-4, and mixtures thereof.

14. The composition according to Claim 13, wherein the amount of the (e) polysaccharide(s) in the composition ranges from 0.001% to 3% by weight, preferably from 0.005% to 2% by weight, and more preferably from 0.01% to 1% by weight, relative to the total weight of the composition.

15. A cosmetic process for treating a keratin substance, comprising the step of applying the composition according to any one of Claims 1 to 14 to the keratin substance.

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