WO2023068069A1

WO2023068069A1 - Composition comprising two polyglyceryl fatty acid esters and skincare active agent

Info

Publication number: WO2023068069A1
Application number: PCT/JP2022/037525
Authority: WO
Inventors: Rui Niimi; Yukinori Yamada
Original assignee: L'oreal
Priority date: 2021-10-21
Filing date: 2022-09-30
Publication date: 2023-04-27

Abstract

The present invention relates to a composition in the form of a nano- or micro-emulsion, comprising: (a) at least one optional oil; (b) at least one first polyglyceryl fatty acid ester having an HLB value of 13.0 or more, preferably 13.5 or more, and more preferably 14.0 or more; (c) at least one second polyglyceryl fatty acid ester having an HLB value of 10.0 or less, preferably 9.0 or less, and more preferably 8.0 or less; (d) at least one skincare active agent; and (e) water, wherein the weight ratio of the amount of the (b) first polyglyceryl fatty acid ester/the amount of the (c) second polyglyceryl fatty acid ester is 3.0 or more, preferably 4.0 or more, and even more preferably 5.0 or more; the weight ratio of the amount of the (a) oil/the total amount of the (b) first polyglyceryl fatty acid ester and the (c) second polyglyceryl fatty acid ester is 0.5 or less; and the composition comprises 0.1% by weight or less of anionic surfactant(s), preferably 0.01% by weight or less of anionic surfactant(s), and more preferably no anionic surfactant. The composition according to the present invention can be in the form of a nano- or micro-emulsion although it comprises at least two different types of polyglyceryl fatty acid esters as well as at least one skincare active agent.

Description

DESCRIPTION

TITLE OF INVENTION

COMPOSITION COMPRISING

TWO POLYGLYCERYL FATTY ACID ESTERS AND SKINCARE ACTIVE AGENT

TECHNICAL FIELD

The present invention relates to a composition, preferably a cosmetic or dermatological composition, which comprises at least two polyglyceryl fatty acid esters, as well as at least one skincare active agent.

BACKGROUND ART

Oil-in-water (O/W) or water-in-oil (W/O) emulsions are well known in the field of cosmetics and dermatology, in particular for the preparation of cosmetic products, such as milks, creams, tonics, serums and lotions.

In particular, a fine emulsion such as an O/W nano- or micro-emulsion is particularly interesting in cosmetic products due to its transparent or slightly translucent aspect.

On the other hand, compositions including a polyglyceryl fatty acid ester have been known in the fields of cosmetics and dermatology. Polyglyceryl fatty acid esters can function as surfactants, and therefore, they may be used to prepare, typically, emulsions such as oil-in-water (O/W) or water-in-oil (W/O) emulsions. Polyglyceryl fatty acid esters are preferable for environmental reasons, such as low environmental load, as compared to polyoxyethylene-based surfactants.

WO 2020/ 110716 discloses a composition in the form of a nano- or micro-emulsion, comprising at least two different types of polyglyceryl fatty acid esters.

DISCLOSURE OF INVENTION

However, the composition disclosed in WO 2020/ 110716 has been found to be unstable such that it can no longer be in the form of a nano- or micro-emulsion when a skincare active agent such as lactic acid and niacinamide is added to the composition.

An objective of the present invention is to provide a composition in the form of a nano- or microemulsion which comprises at least two different types of polyglyceryl fatty acid esters even when the composition also comprises a skincare active agent.

The above objective of the present invention can be achieved by a composition in the form of a nano- or micro-emulsion, comprising:

(a) at least one optional oil;

(b) at least one first polyglyceiyl fatty acid ester having an HLB value of 13.0 or more, preferably 13.5 or more, and more preferably 14.0 or more;

(c) at least one second polyglyceryl fatty acid ester having an HLB value of 10.0 or less, preferably 9.0 or less, and more preferably 8.0 or less;

(d) at least one skincare active agent; and

(e) water, wherein the weight ratio of the amount of the (b) first polyglyceryl fatty acid ester/the amount of the (c) second polyglyceryl fatty acid ester is 3.0 or more, preferably 4.0 or more, and even more preferably 5.0 or more, the weight ratio of the amount of the (a) oil/the total amount of the (b) first poly glyceryl fatty acid ester and the (c) second polyglyceryl fatty acid ester is 0.5 or less, and the composition comprises 0.1% by weight or less of anionic surfactant(s), preferably 0.01% by weight or less of anionic surfactant(s), and more preferably no anionic surfactant.

The composition according to the present invention may have a turbidity of 300 NTU or less, preferably 200 NTU or less, and more preferably 100 NTU or less.

The (a) oil may be selected from polar oils.

The (a) oil(s) in the composition according to the present invention may range from 10% by weight or less, preferably 5% by weight or less, and more preferably from 1 % by weight or less, relative to the total weight of the composition.

The (b) first polyglyceryl fatty acid ester may comprise 2 to 4 glycerol units, preferably 3 or 4 glycerol units, and more preferably 4 glycerol units.

The fatty acid moiety of the (b) first polyglyceryl fatty acid ester may comprise 12 or fewer carbon atoms, preferably 11 or fewer carbon atoms, and more preferably 10 or fewer carbon atoms.

The (c) second polyglyceiyl fatty acid ester may comprise 2 to 4 glycerol units, preferably 2 or 3 glycerol units, and more preferably 2 glycerol units.

The fatty acid moiety of the (c) second polyglyceiyl fatty acid ester may comprise 14 or more carbon atoms, preferably 16 or more carbon atoms, and more preferably 18 or more carbon atoms.

The total amount of the (b) first polyglyceryl fatty acid ester and the (c) second polyglyceryl fatty acid ester may be 0.05% by weight or more, preferably 0.1% weight or more, and more preferably 1% by weight or more of the composition.

The (d) skincare active agent may be selected from the group consisting of lactic acid, niacinamide and mixtures thereof.

The amount of the (d) skincare active agent may be from 0.01% to 25% by weight, preferably from 0.05% to 20% by weight, and more preferably from 0.1 % to 15% by weight, relative to the total weight of the composition.

The pH of the composition may be from 3.5 to 9.0, preferably from 4.0 to 8.0, more preferably from 4.5 to 7.0, and even more preferably from 4.0 to 6.0.

The composition according to the present invention may be in the form of a nano- or micro- O/W emulsion. The particle size of the (a) oil may be 300 nm or less, preferably 200 nm or less, and more preferably 100 nm or less.

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. BEST MODE FOR CARRYING OUT TEE INVENTION

After diligent research, the inventors have discovered that it is possible to provide a composition in the form of a nano- or micro-emulsion which comprises at least two different types of polyglyceryl fatty acid esters even when the composition also comprises a skincare active agent.

The composition according to the present invention can be in the form of a nano- or microemulsion although it comprises at least two polyglyceryl fatty acid esters as well as at least one skincare active agent.

One of the features of the composition according to the present invention is a combination of: at least one first polyglyceryl fatty acid ester having a higher HLB value; and at least one second polyglyceryl fatty acid ester having a lower HLB value.

The HLB value of the first polyglyceryl fatty acid ester may belong to a higher HLB numerical range, the HLB value of the second polyglyceryl fatty acid ester may belong to a lower HLB numerical range, and the higher HLB numerical range and the lower HLB numerical range do not overlap each other.

Another feature of the composition according to the present invention is the presence of at least one skincare active agent therein with the above combination of the first and second polyglyceryl fatty acid esters. Although the composition according to the present invention comprises a skincare active agent, it can be stable such that it can maintain the form of a nano- or microemulsion.

One of the aspect of the present invention relates to a composition in the form of a nano-or micro emulsion, comprising:

(a) at least one optional oil;

(c) at least one second polyglyceiyl fatty acid ester having an HLB value of 10.0 or less, preferably 9.0 or less, and more preferably 8.0 or less;

(d) at least one skincare active agent; and

(e) water, wherein the weight ratio of the amount of the (b) first polyglyceiyl fatty acid ester/the amount of the (c) second polyglyceiyl fatty acid ester is 3.0 or more, preferably 4.0 or more, and even more preferably 5.0 or more, the weight ratio of the amount of the (a) oil/the total amount of the (b) first polyglyceiyl fatty acid ester and the (c) second polyglyceryl fatty acid ester is 0.5 or less, and the composition comprises 0.1% by weight or less of anionic surfactant(s), preferably 0.01% by weight or less of anionic surfactant(s), and more preferably no anionic surfactant.

The composition according to the present invention may be transparent or translucent because it can have a turbidity of 300 NTU or less, preferably 200 NTU or less, and more preferably 100 NTU or less.

The composition according to the present invention may be prepared without a large amount of energy such as required by a homogenizer. Thus, the composition according to the present invention may be prepared by using a small amount of energy such as gently stirring the ingredients of the composition. Therefore, the composition according to the present invention is environmentally friendly in view of the preparation approach thereof.

Hereinafter, the composition according to the present invention will be explained in a more detailed manner.

[Oil]

The composition according to the present invention comprises (a) at least one optional oil. If two or more oils are used, they may be the same or different.

Here, “oil” means a fatty compound or substance which is in the form of a liquid or a paste (nonsolid) at room temperature (25 °C) under atmospheric pressure (760 mmHg). As the oils, those generally used in cosmetics can be used alone or in combination thereof. These oils may be volatile or non-volatile.

The (a) oil may be a non-polar oil such as a hydrocarbon oil, a silicone oil, or the like; a polar oil such as a plant or animal oil and an ester oil or an ether oil; or a mixture thereof.

The (a) oil may be selected from the group consisting of oils of plant or animal origin, synthetic oils, silicone oils, hydrocarbon oils, and fatty alcohols.

As examples of plant oils, mention may be made of, for example, linseed oil, camellia oil, macadamia nut oil, com oil, mink oil, olive oil, avocado oil, sasanqua oil, castor oil, safflower oil, jojoba oil, sunflower oil, almond oil, rapeseed oil, sesame oil, soybean oil, peanut oil, and mixtures thereof.

As examples of animal oils, mention may be made of, for example, squalene and squalane.

As examples of synthetic oils, mention may be made of alkane oils such as isododecane and isohexadecane, ester oils, ether oils, and artificial triglycerides.

The ester oils are preferably liquid esters of saturated or unsaturated, linear or branched C₁-C₂₆ aliphatic monoacids or polyacids and of saturated or unsaturated, linear or branched C₁-C₂₆ aliphatic monoalcohols or polyalcohols, the total number of carbon atoms of the esters being greater than or equal to 10.

Preferably, for the esters of monoalcohols, at least one from among the alcohol and the acid from which the esters of the present invention are derived is branched.

Among the monoesters of monoacids and of monoalcohols, mention may be made of ethyl palmitate, ethyl hexyl palmitate, isopropyl palmitate, dicaprylyl carbonate, alkyl myristates such as isopropyl myristate or ethyl myristate, isocetyl stearate, 2-ethylhexyl isononanoate, isononyl isononanoate, isodecyl neopentanoate, and isostearyl neopentanoate.

Esters of C₄-C₂₂ dicarboxylic or tricarboxylic acids and of C₁-C₂₂ alcohols, and esters of monocarboxylic, dicarboxylic, or tricarboxylic acids and of non-sugar C₄-C₂₆ dihydroxy, trihydroxy, tetrahydroxy, or pentahydroxy alcohols may also be used. Mention may especially be made of: diethyl sebacate; isopropyl lauroyl sarcosinate; diisopropyl sebacate; bis(2-ethylhexyl) sebacate; diisopropyl adipate; di-n-propyl adipate; dioctyl adipate; bis(2 -ethylhexyl) adipate; diisostearyl adipate; bis(2-ethylhexyl) maleate; triisopropyl citrate; triisocetyl citrate; triisostearyl citrate; glyceryl trilactate; glyceryl trioctanoate; trioctyldodecyl citrate; trioleyl citrate; neopentyl glycol diheptanoate; diethylene glycol diisononanoate.

As ester oils, one can use sugar esters and diesters of C₆-C₃₀ and preferably C₁₂-C₂₂ fatty acids. It is recalled that the term “sugar” means oxygen-bearing hydrocarbon-based compounds containing several alcohol functions, with or without aldehyde or ketone functions, and which comprise at least 4 carbon atoms. These sugars may be monosaccharides, oligosaccharides, or polysaccharides.

Examples of suitable sugars that may be mentioned include sucrose (or saccharose), glucose, galactose, ribose, fucose, maltose, fructose, mannose, arabinose, xylose, and lactose, and derivatives thereof, especially alkyl derivatives, such as methyl derivatives, for instance, methylglucose.

The sugar esters of fatty acids may be chosen especially from the group comprising the esters or mixtures of esters of sugars described previously and of linear or branched, saturated or unsaturated C₆-C₃₀ and preferably C₁₂-C₂₂ fatty acids. If they are unsaturated, these compounds may have one to three conjugated or non-conjugated carbon-carbon double bonds.

The esters according to this variant may also be selected from monoesters, diesters, triesters, tetraesters, and polyesters, and mixtures thereof.

These esters may be, for example, oleates, laurates, palmitates, myristates, behenates, cocoates, stearates, linoleates, linolenates, caprates, and arachidonates, or mixtures thereof such as, especially, oleopalmitate, oleostearate, and palmitostearate mixed esters, as well as pentaerythrityl tetraethyl hexanoate.

More particularly, use is made of monoesters and diesters and especially sucrose, glucose, or methylglucose monooleates or dioleates, stearates, behenates, oleopahnitates, linoleates, linolenates, and oleostearates.

An example that may be mentioned is the product sold under the name Glucate® DO by the company Amerchol, which is a methylglucose dioleate.

As examples of preferable ester oils, mention may be made of, for example, diisopropyl adipate, dioctyl adipate, 2-ethylhexyl hexanoate, ethyl laurate, cetyl octanoate, octyldodecyl octanoate, isodecyl neopentanoate, myristyl propionate, 2-ethylhexyl 2-ethylhexanoate, 2-ethylhexyl octanoate, 2-ethylhexyl capiylate/caprate, methyl palmitate, ethyl palmitate, isopropyl palmitate, dicaprylyl carbonate, isopropyl lauroyl sarcosinate, isononyl isononanoate, ethylhexyl palmitate, isohexyl laurate, hexyl laurate, isocetyl stearate, isopropyl isostearate, isopropyl myristate, isodecyl oleate, glyceryl tri(2-ethylhexanoate), pentaerythrithyl tetra(2-ethylhexanoate), 2- ethylhexyl succinate, diethyl sebacate, and mixtures thereof.

As examples of artificial triglycerides, mention may be made of, for example, capryl caprylyl glycerides, glyceryl trimyristate, glyceryl tripalmitate, glyceryl trilinolenate, glyceryl trilaurate, glyceryl tricaprate, glyceryl tricaprylate, glyceryl tri(caprate/caprylate), and glyceryl tri(caprate/caprylate/linolenate) . As examples of silicone oils, mention may be made of, for example, linear organopolysiloxanes such as dimethylpolysiloxane, methylphenylpolysiloxane, methylhydrogenpolysiloxane, and the like; cyclic organopolysiloxanes such as cyclohexasiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, and the like; and mixtures thereof.

Preferably, the silicone oil is chosen from liquid polydialkylsiloxanes, especially liquid polydimethylsiloxanes (PDMS) and liquid polyorganosiloxanes comprising at least one aryl group.

These silicone oils may also be organomodified. The organomodified silicones that can be used in accordance with the present invention are silicone oils as defined above and comprise in their structure one or more organofunctional groups attached via a hydrocarbon-based group.

Organopolysiloxanes are defined in greater detail in Walter Noll’s Chemistry and Technology of Silicones (1968), Academic Press. They may be volatile or non-volatile.

When they are volatile, the silicones are more particularly chosen from those having a boiling point of between 60°C and 260°C, and even more particularly from:

(i) cyclic polydialkylsiloxanes comprising from 3 to 7 and preferably 4 to 5 silicon atoms. These are, for example, octamethylcyclotetrasiloxane sold in particular under the name Volatile Silicone® 7207 by Union Carbide or Silbione® 70045 V2 by Rhodia, decamethylcyclopentasiloxane sold under the name Volatile Silicone® 7158 by Union Carbide, Silbione® 70045 V5 by Rhodia, and dodecamethylcyclopentasiloxane sold under the name Silsoft 1217 by Momentive Performance Materials, and mixtures thereof. Mention may also be made of cyclocopolymers of the type such as dimethylsiloxane/methylalkylsiloxane, such as Silicone Volatile® FZ 3109 sold by the company Union Carbide, of the formula:

Mention may also be made of mixtures of cyclic polydialkylsiloxanes with organosilicon compounds, such as the mixture of octamethylcyclotetrasiloxane and tetratrimethylsilylpentaerythritol (50/50) and the mixture of octamethylcyclotetrasiloxane and oxy-l,l’-bis(2,2,2’,2’,3,3’-hexatrimethylsilyloxy)neopentane; and

(ii) linear volatile polydialkylsiloxanes containing 2 to 9 silicon atoms and having a viscosity of less than or equal to 5 x 10^-6 m²/s at 25°C. An example is decamethyltetrasiloxane sold in particular under the name SH 200 by the company Toray Silicone. Silicones belonging to this category are also described in the article published in Cosmetics and Toiletries, Vol. 91, Jan. 76, pp. 27-32, Todd & Byers, Volatile Silicone Fluids for Cosmetics. The viscosity of the silicones is measured at 25°C according to ASTM standard 445 Appendix C. Non-volatile polydialkylsiloxanes may also be used. These non-volatile silicones are more particularly chosen from polydialkylsiloxanes, among which mention may be made mainly of polydimethylsiloxanes containing trimethylsilyl end groups.

Among these polydialkylsiloxanes, mention may be made, in a non-limiting manner, of the following commercial products: the Silbione® oils of the 47 and 70 047 series or the Mirasil® oils sold by Rhodia, for instance the oil 70 047 V 500 000; the oils of the Mirasil® series sold by the company Rhodia; the oils of the 200 series from the company Dow Coming, such as DC200 with a viscosity of 60000 mm²/s; and the Viscasil® oils from General Electric and certain oils of the SF series (SF 96, SF 18) from General Electric.

Mention may also be made of polydimethylsiloxanes containing dimethylsilanol end groups known under the name dimethiconol (CTFA), such as the oils of the 48 series from the company Rhodia.

Among the silicones containing aryl groups, mention may be made of polydiaryl siloxanes, especially polydiphenylsiloxanes and polyalkylarylsiloxanes such as phenyl silicone oil.

The phenyl silicone oil may be chosen from the phenyl silicones of the following formula:

in which

R₁ to R₁₀, independently of each other, are saturated or unsaturated, linear, cyclic or branched C₁- C₃₀ hydrocarbon-based radicals, preferably C₁-C₁₂ hydrocarbon-based radicals, and more preferably C₁-C₆ hydrocarbon-based radicals, in particular methyl, ethyl, propyl, or butyl radicals, and m, n, p, and q are, independently of each other, integers of 0 to 900 inclusive, preferably 0 to 500 inclusive, and more preferably 0 to 100 inclusive, with the proviso that the sum n+m+q is other than 0.

Examples that may be mentioned include the products sold under the following names: the Silbione® oils of the 70 641 series from Rhodia; the oils of the Rhodorsil® 70 633 and 763 series from Rhodia; the oil Dow Coming 556 Cosmetic Grade Fluid from Dow Coming; the silicones of the PK series from Bayer, such as the product PK20; certain oils of the SF series from General Electric, such as SF 1023, SF 1154, SF 1250, and SF 1265. As the phenyl silicone oil, phenyl trimethicone (R₁ to R₁₀ are methyl; p, q, and n = 0; m=1 in the above formula) is preferable.

The organomodified liquid silicones may especially contain polyethyleneoxy and/or polypropyleneoxy groups. Mention may thus be made of the silicone KF-6017 proposed by Shin-Etsu, and the oils Silwet® L722 and L77 from the company Union Carbide.

The hydrocarbon oils may be chosen from: linear or branched, optionally cyclic, C₆-C₁₆ lower alkanes. Examples that may be mentioned include hexane, undecane, dodecane, tridecane, and isoparaffins, for instance isohexadecane, isododecane, and isodecane; and linear or branched hydrocarbons containing more than 16 carbon atoms, such as liquid paraffins, liquid petroleum jelly, polydecenes and hydrogenated polyisobutenes such as Parleam®, and squalane.

As preferable examples of hydrocarbon oils, mention may be made of, for example, linear or branched hydrocarbons such as isohexadecane, isododecane, squalane, mineral oil (e.g., liquid paraffin), paraffin, vaseline or petrolatum, naphthalenes, and the like; hydrogenated polyisobutene, isoeicosan, and decene/butene copolymer; and mixtures thereof.

The term “fatty” in the fatty alcohol means the inclusion of a relatively large number of carbon atoms. Thus, alcohols which have 4 or more, preferably 6 or more, and more preferably 12 or more carbon atoms are encompassed within the scope of fatty alcohols. The fatty alcohol may be saturated or unsaturated. The fatty alcohol may be linear or branched.

The fatty alcohol may have the structure R-OH wherein R is chosen from saturated and unsaturated, linear and branched radicals containing from 4 to 40 carbon atoms, preferably from 6 to 30 carbon atoms, and more preferably from 12 to 20 carbon atoms. In at least one embodiment, R may be chosen from C₁₂-C₂₀ alkyl and C₁₂-C₂₀ alkenyl groups. R may or may not be substituted with at least one hydroxyl group.

As examples of the fatty alcohol, mention may be made of lauryl alcohol, cetyl alcohol, stearyl alcohol, isostearyl alcohol, behenyl alcohol, undecylenyl alcohol, myristyl alcohol, octyldodecanol, hexyldecanol, oleyl alcohol, linoleyl alcohol, palmitoleyl alcohol, arachidonyl alcohol, erucyl alcohol, and mixtures thereof.

It is preferable that the fatty alcohol be a saturated fatty alcohol.

Thus, the fatty alcohol may be selected from straight or branched, saturated or unsaturated C₆-C₃₀ alcohols, preferably straight or branched, saturated C₆-C₃₀ alcohols, and more preferably straight or branched, saturated C₁₂-C₂₀ alcohols.

The term “saturated fatty alcohol” here means an alcohol having a long aliphatic saturated carbon chain. It is preferable that the saturated fatty alcohol be selected from any linear or branched, saturated C₆-C₃₀ fatty alcohols. Among the linear or branched, saturated C₆-C₃₀ fatty alcohols, linear or branched, saturated C₁₂-C₂₀ fatty alcohols may preferably be used. Any linear or branched, saturated C₁₆-C₂₀ fatty alcohols may be more preferably used. Branched C₁₆-C₂₀ fatty alcohols may be even more preferably used. As examples of saturated fatty alcohols, mention may be made of lauryl alcohol, cetyl alcohol, stearyl alcohol, isostearyl alcohol, behenyl alcohol, undecylenyl alcohol, myristyl alcohol, octyldodecanol, hexyldecanol, and mixtures thereof. In one embodiment, cetyl alcohol, stearyl alcohol, octyldodecanol, hexyldecanol, or a mixture thereof (e.g., cetearyl alcohol) as well as behenyl alcohol, can be used as a saturated fatty alcohol.

According to at least one embodiment, the fatty alcohol used in the composition according to the present invention is preferably chosen from cetyl alcohol, octyldodecanol, hexyldecanol, and mixtures thereof.

It is also preferable that the (a) oil be chosen from oils with a molecular weight below 600 g/mol.

Preferably, the (a) oil has a low molecular weight such as below 600 g/mol, chosen among ester oils with a short hydrocarbon chain or chains (C₁-C₁₂) (e.g., isopropyl lauroyl sarcosinate, isopropyl myristate, isopropyl palmitate, isononyl isononanoate, and ethyl hexyl palmitate), silicone oils (e.g., volatile silicones such as cyclohexasiloxane), hydrocarbon oils (e.g., isododecane, isohexadecane, and squalane), branched and/or unsaturated fatty alcohol (C₁₂-C₃₀) type oils such as octyldodecanol and oleyl alcohol, and ether oils such as dicaprylyl ether.

It is preferable that the (a) oil be chosen from polar oils, and more preferably from ester oils.

The (a) oil can constitute dispersed phases of the composition according to the present invention, with or without any other possible hydrophobic ingredient(s) in the composition.

The (a) oil is optional. Therefore, the composition according to the present invention may or may not comprise the (a) oil. If the composition according to the present invention does not comprise the (a) oil, the dispersed phases of the composition according to the present invention can be formed by, at least, the (b) first polyglyceryl fatty acid ester and the (c) second polyglyceryl fatty acid ester, explained below.

It is preferable that the composition according to the present invention comprise the (a) oil. If the composition according to the present invention comprises the (a) oil, it may be possible to provide skin moisturizing effects due to the (a) oil and/or to enhance the penetration of the (d) skincare active agent, explained below.

The amount of the (a) oil(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.

The amount of the (a) 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.

The amount of the (a) oil(s) in the composition according to the present invention may be from 0.001% to 10% by weight, preferably from 0.005% to 5% by weight, and more preferably from 0.01% to 1% by weight, relative to the total weight of the composition.

[First Polyglyceiyl Fatty Acid Ester]

The composition according to the present invention comprises (b) at least one first polyglyceryl fatty acid ester having an HLB value of 13.0 or more, preferably 13.5 or more, and more preferably 14.0 or more. A single type of (b) first polyglyceryl fatty acid ester may be used, but two or more different types of (b) first polyglyceryl fatty acid ester may be used in combination.

The (b) first polyglyceryl fatty acid ester can function as a surfactant, in particular a nonionic surfactant.

The (b) first polyglyceryl fatty acid ester may have an HLB value of 13.0 to 17.0, preferably 13.5 to 16.0, and more preferably 14.0 to 15.0.

The term HLB ("hydrophilic-lipophilic balance") is well known to those skilled in the art, and reflects the ratio between the hydrophilic part and the lipophilic part in the molecule.

If two or more (b) first polyglyceryl fatty acid esters are used, the HLB value is determined by the weighted average of the HLB values of all the (b) first polyglyceiyl fatty acid esters.

The (b) first polyglyceryl fatty acid ester may be chosen from mono, di, tri and more esters of saturated or unsaturated fatty acid(s).

It is preferable that the (b) first polyglyceiyl fatty acid ester comprises 2 to 4 glycerol units, preferably 3 or 4 glycerol units, and more preferably 4 glycerol units.

The fatty acid for the fatty acid moiety or the fatty acid moiety of the (b) first polyglyceryl fatty acid ester may comprise 12 or fewer carbon atoms, preferably 11 or fewer carbon atoms, and more preferably 10 or fewer carbon atoms. The fatty acid for the fatty acid moiety or the fatty acid moiety of the (b) first polyglyceryl fatty acid ester may comprise 4 or more carbon atoms, preferably 6 or more carbon atoms, and more preferably 8 or more carbon atoms. The fatty acid for the fatty acid moiety or the fatty acid moiety of the (b) first polyglyceryl fatty acid ester may have carbon atoms of from 4 to 12, preferably from 6 to 11, and more preferably from 8 to 10 carbon atoms.

The fatty acid for the fatty acid moiety of the (b) first polyglyceryl fatty acid ester may be saturated or unsaturated, and may be selected from caprylic acid, capric acid, and lauric acid.

The (b) first polyglyceryl fatty acid ester(s) may be selected from the group consisting of PG3 caprate (HLB: about 14), PG4 caprylate (HLB: 14), PG4 laurate (HLB: about 14), PG4 caprate (HLB: 14), PG5 myristate (HLB: 15.4), PG5 stearate (HLB: 15), PG6 caprylate (HLB: 14.6), PG6 caprate (HLB: 13.1), PG6 laurate (HLB: 14.1), PG10 laurate (HLB: 15.2), PG10 myristate (HLB: 14.9), PG10 stearate (HLB: 14.1), PG10 isostearate (HLB: 13.7), PG10 oleate (HLB: 13.0), PG10 cocoate (HLB: 16), and mixtures thereof.

It may be preferable that the (b) first polyglyceryl fatty acid ester(s) be selected from the group consisting of PG3 caprate (HLB: about 14), PG4 caprylate (HLB: 14), PG4 laurate (HLB: about 14), PG4 caprate (HLB: 14), and mixtures thereof.

The amount of the (b) first polyglyceryl fatty acid ester(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.

On the other hand, the amount of the (b) first polyglyceryl fatty acid ester(s) in the composition according to the present invention may be 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.

The amount of the (b) first polyglyceryl fatty acid ester(s) in the composition according to the present invention may range from 0.01% to 15% by weight, preferably from 0.05% to 10% by weight, and more preferably from 0.1% to 5% by weight, relative to the total weight of the composition.

The weight ratio of the amount of the (b) first polyglyceryl fatty acid ester(s)/the amount of the (a) oil(s) in the composition according to the present invention may be 1 or more, preferably 1.5 or more, and more preferably 2 or more.

The weight ratio of the amount of the (b) first polyglyceryl fatty acid ester(s)/the amount of the (a) oil(s) in the composition according to the present invention may be 10 or less, preferably 9.5 or less, and more preferably from 9 or less.

The weight ratio of the amount of the (b) first polyglyceryl fatty acid ester(s)/the amount of the (a) oil(s) in the composition according to the present invention may range from 1 to 10, preferably from 1.5 to 9.5, and more preferably from 2 to 9.

[Second Polyglyceryl Fatty Acid Ester]

The composition according to the present invention comprises (c) at least one second polyglyceryl fatty acid ester having an HLB value of 10.0 or less, preferably 9.0 or less, and more preferably 8.0 or less. A single type of (c) second polyglyceryl fatty acid ester may be used, but two or more different types of (c) second polyglyceryl fatty acid ester may be used in combination.

The (c) second polyglyceryl fatty acid ester can function as a surfactant, in particular a nonionic surfactant.

The (c) second polyglyceryl fatty acid ester may have an HLB value of 5.0 to 10.0, preferably 6.0 to 9.0, and more preferably 7.0 to 8.0.

If two or more (c) second polyglyceryl fatty acid esters are used, the HLB value is determined by the weighted average of the HLB values of all the (c) second polyglyceryl fatty acid esters.

The (c) second polyglyceryl fatty acid ester may be chosen from mono, di, tri and more esters of saturated or unsaturated fatty acid(s).

It is preferable that the (c) second polyglyceryl fatty acid ester comprises 2 to 4 glycerol units, preferably 2 or 3 glycerol units, and more preferably 2 glycerol units.

The fatty acid for the fatty acid moiety or the fatty acid moiety of the (c) second polyglyceryl fatty acid ester may comprise 14 or more carbon atoms, preferably 16 or more carbon atoms, and more preferably 18 or more carbon atoms. The fatty acid for the fatty acid moiety or the fatty acid moiety of the (c) second polyglyceryl fatty acid ester may comprise 30 or fewer carbon atoms, preferably 24 or fewer carbon atoms, and more preferably 20 or fewer carbon atoms. The fatty acid for the fatty acid moiety or the fatty acid moiety of the (c) second polyglyceryl fatty acid ester may have from 14 to 30, preferably from 16 to 24, and more preferably from 18 to 20 carbon atoms. The fatty acid for the fatty acid moiety of the (c) second polyglyceryl fatty acid ester may be saturated or unsaturated, and may be selected from myristic acid, stearic acid, isostearic acid, and oleic acid.

The (c) second polyglyceryl fatty acid ester(s) may be selected from the group consisting of PG2 stearate (HLB: 5.0), PG2 distearate (HLB: 4), PG2 isostearate (HLB: 8), PG2 diisostearate (HLB: 3.2), PG2 triisostearate (HLB: 3), PG2 sesquiisostearate (HLB: about 4), PG2 oleate (HLB: 8), PG2 sesquioleate (HLB: 5.3), PG3 distearate (HLB: 5), PG3 diisostearate (HLB: 5), PG3 dicocoate (HLB: 7), PG5 hexastearate (HLB: 4.0), PG5 trioleate (HLB: 7.0), PG 10 pentaoleate (HLB: 6.4), PG2 sesquicaprylate (HLB: about 8), PG2 caprate (HLB: 9.5), PG2 laurate (HLB: 8.5), PG2 myristate (HLB: 10), PG2 isopalmitate (HLB: 9), PG4 oleate (HLB: 10), PG4 stearate (HLB: 9), PG4 isostearate (HLB: 8.2), PG6 distearate (HLB: 8), PG10 distearate (HLB: about 9), PG10 tristearate (HLB: 8), PG10 diisostearate (HLB: 10), PG10 triisostearate (HLB: 8), PG10 tricocoate (HLB: 9), and mixtures thereof.

It may be preferable that the (c) second polyglyceryl fatty acid ester be selected from the group consisting of PG2 stearate (HLB: 5.0), PG2 distearate (HLB: 4), PG2 isostearate (HLB: 8), PG2 diisostearate (HLB: 3.2), PG2 triisostearate (HLB: 3), PG2 sesquiisostearate (HLB: about 4), PG2 oleate (HLB: 8), PG2 sesquioleate (HLB: 5.3), PG3 distearate (HLB: 5), PG3 diisostearate (HLB: 5), PG3 dicocoate (HLB: 7), PG2 sesquicaprylate (HLB: about 8), PG2 caprate (HLB: 9.5), PG2 laurate (HLB: 8.5), PG2 myristate (HLB: 10), PG2 isopahnitate (HLB: 9), PG4 oleate (HLB: 10), PG4 stearate (HLB: 9), PG4 isdstearate (HLB: 8.2), and mixtures thereof.

The amount of the (c) second polyglyceryl fatty acid ester(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.

On the other hand, the amount of the (c) second poly glyceryl fatty acid ester(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.

The amount of the (c) second polyglyceryl fatty acid ester(s) in the composition according to the present invention may range from 0.01% to 10% by weight, preferably from 0.05% to 5% by weight, more preferably from 0.1% to 1% by weight, relative to the total weight of the composition.

The weight ratio of the amount of the (c) second polyglyceryl fatty acid ester(s)/the amount of the (a) oil(s) in the composition according to the present invention may be 0.1 or more, preferably 0.2 or more, and more preferably 0.25 or more.

The weight ratio of the amount of the (c) second polyglyceryl fatty acid ester(s)/the amount of the (a) oil(s) in the composition according to the present invention may be 4 or less, preferably 3 or less, and more preferably 2 or less.

The weight ratio of the amount of the (c) second poly glyceryl fatty acid ester(s)/the amount of the (a) oil(s) in the composition according to the present invention may range from 0.1 to 4, preferably from 0.2 to 3, and more preferably from 0.25 to 2.

[Weight Ratio of Oil/First and Second Polyglyceryl Fatty Acid Esters] According to the present invention, the weight ratio of the amount of the (a) oil/(the total amount of the (b) first polyglyceryl fatty acid ester(s) and the (c) second polyglyceryl fatty acid ester(s)) is 0.5 or less, preferably 0.45 or less, and more preferably 0.4 or less.

The weight ratio of the amount of the (a) oil/(the total amount of the (b) first polyglyceryl fatty acid ester(s) and the (c) second polyglyceryl fatty acid ester(s)) may be 0.01 or more, preferably 0.03 or more, and more preferably 0.05 or more.

The weight ratio of the amount of the (a) oil/(the total amount of the (b) first polyglyceryl fatty acid ester(s) and the (c) second polyglyceiyl fatty acid ester(s)) may be from 0.01 to 0.5, preferably from 0.03 to 0.45, and more preferably from 0.05 to 0.4.

[Weight Ratio of First Polyglyceiyl Fatty Acid Ester(s)/Second Polyglyceryl Fatty Acid Ester(s)]

The weight ratio of the amount of the (b) first polyglyceiyl fatty acid ester/the amount of the (c) second polyglyceiyl fatty acid ester is 3.0 or more, preferably 4.0 or more, and even more preferably 5.0 or more.

The weight ratio of the amount of the (b) first poly glyceryl fatty acid ester/the amount of the (c) second polyglyceryl fatty acid ester may be 20 or less, preferably 19 or less, and more preferably 18 or less.

The weight ratio of the amount of the (b) first polyglyceiyl fatty acid ester/the amount of the (c) second polyglyceryl fatty acid ester may be from 3.0 to 20, preferably from 4.0 to 19, and more preferably from 5.0 to 18.

[Skincare Active Agent]

The composition according to the present invention comprises (d) at least one skincare active agent. If two or more skincare active agents are used, they may be the same or different.

It is preferable that the (d) skin care active ingredient has a logP value ranging from -4.5 to 4.5, preferably from -4.0 to 4.0, and more preferably from -3.5 to 3.5.

A log P value is a value for the base-ten logarithm of the apparent octan-1 -o1/water partition coefficient. The log p values are known and are determined by a standard test which determines the concentration of the (c) compound in octan-1 -o1 and water. The log P may be calculated according to the method described in the article by Meylan and Howard: AtondFragment contribution method for estimating octanol-water partition coefficients, J. Pharm. Sci., 84: 83-92, 1995. This value may also be calculated using numerous commercially available software packages, which determine the log P as a function of the structure of a molecule. By way of example, mention may be made of the Epiwin software from the United States Environmental Agency.

The values may especially be calculated using the ACD (Advanced Chemistry Development) Solaris software V4.67; they may also be obtained from Exploring QSAR: hydrophobic, electronic and steric constants (ACS professional reference book, 1995). There is also an Internet site which provides estimated values (address: http://esc.syrres.com/interkow/kowdemo.htm). The (d) skin care active ingredient may be in the form of a salt. The salts of the (d) skin care active ingredient include conventional non-toxic salts of said compounds, such as those formed from an acid or from a base.

It is preferable that the (d) skin care active ingredient be a skin care cosmetic active ingredient, and more preferably a skin peeling agent, a skin whitening agent, or a skin anti-aging agent such as an anti- wrinkle agent.

As the (d) skin care active ingredient, mention may be made of Vitamin B3 and derivatives.

Vitamin B3, also called vitamin PP, is a compound of the following formula:

in which R may be -CONH₂ (niacinamide), -COOH (nicotinic acid or niacin), or CH₂OH (nicotinyl alcohol), -CO-NH-CH₂-COOH (nicotinuric acid) or -CO-NH-OH (niconityl hydroxamic acid). Niacinamide is preferable.

Vitamin B3 derivatives that may be mentioned include, for example, nicotinic acid esters such as tocopherol nicotinate, amides derived from niacinamide by substitution of the hydrogen groups of -CONH₂, products from reaction with carboxylic acids and amino acids, esters of nicotinyl alcohol and of carboxylic acids such as acetic acid, salicyclic acid, glycolic acid or palmitic acid.

Mention may also be made of the following derivatives: 2-chloronicotinamide, 6- methylnicotinamide, 6-aminonicotinamide, N-methylnicotinamide, N,N-dimethylnicotinamide, N-(hydroxymethyl)nicotinamide, quinolinic acid imide, nicotinanilide, N-benzylnicotinamide, N- ethylnicotinamide, nifenazone, nicotinaldehyde, isonicotinic acid, methylisonicotinic acid, thionicotinamide, nialamide, 2-mercaptonicotinic acid, nicomol and niaprazine, methyl nicotinate and sodium nicotinate.

Other vitamin B3 derivatives that may also be mentioned include its inorganic salts, such as chlorides, bromides, iodides or carbonates, and its organic salts, such as the salts obtained by reaction with carboxylic acids, such as acetate, salicylate, glycolate, lactate, malate, citrate, mandelate, tartrate, etc.

As the (d) skin care active ingredient, mention may be made of ascorbic acid and derivatives thereof.

Ascorbic acid is generally in L form, since it is usually extracted from natural products.

On account of its chemical structure (a-keto lactone) which makes it very sensitive to certain environmental parameters such as light, heat and aqueous media, it may be advantageous to use the ascorbic acid in the form of a derivative or an analog chosen, for example, from saccharide esters of ascorbic acid or metal salts of phosphoryl ascorbic acid, alkali metal salts, esters and sugars.

The saccharide esters of ascorbic acid that may be used in the present invention are especially the glycosyl, mannosyl, fructosyl, fucosyl, galactosyl, N-acetylglucosamine and N-acetylmuramic derivatives of ascorbic acid, and mixtures thereof, and more especially ascorbyl glucoside such as ascorbyl-2 glucoside, 2-O-a-D-glucopyranosyl L-ascorbic acid or 6-O-β-D-galactopyranosyl L- ascorbic acid. The latter compounds and processes for preparing them are described in particular in documents EP-A-0487404, EP-A-0425 066 and JP 05 213 736.

In regards to the metal salt of phosphoryl ascorbic acid, it may be chosen from alkali metal, and especially sodium, ascorbyl phosphates, alkaline-earth metal ascorbyl phosphates and transition metal ascorbyl phosphates.

It is also possible to use ascorbic acid precursors such as active agent amides and active agent saccharide derivatives, which respectively involve proteases or peptidases and glycosidases as enzymes for releasing ascorbic acid in situ. Such compounds are described in patent EP 0667 145.

The active agent saccharide derivatives are especially chosen from C3 to C& saccharide derivatives. They are especially chosen from glucosyl, mannosyl, fructosyl, fucosyl, N- acetylglucosamine, galactosyl and N-acetylgalactosamine derivatives, N-acetylmuramic acid derivatives and sialic acid derivatives, and mixtures thereof.

The second ascorbic acid precursors may be chosen from derivatives that are hydrolyzed by other enzymes, for example by esterases, phosphatases, sulfatases, etc. According to the present invention, the second active agent precursors may be chosen, for example, from phosphates; sulfates; palmitates; acetates; propionates; ferulates, and, in general, active agent alkyl or acyl esters; acyl or alkyl ethers. The acyl and alkyl radicals in particular contain from 1 to 30 carbon atoms. As the skin care active ingredient, mention may be made of 3-O-ethyl ascorbic acid.

In particular, the second precursor may be an ester derived from the reaction with a mineral acid such as a sulfate or a phosphate to react with a sulfatase or phosphatase on contact with the skin, and the second precursor may be an acyl or alkyl ester derived from the reaction with an organic acid, for instance palmitic acid, acetic acid, propionic acid, nicotinic acid, 1,2,3- propanetricarboxylic acid or ferulic acid to react with a specific skin esterase.

Other derivatives are described, for example, in patent EP 1 430 883.

The ascorbic acid analogs are, more particularly, its salts, especially alkali metal salts, for example sodium ascorbate, its esters, especially such as its acetic, propionic or palmitic esters, or its sugars, especially such as glycosyl ascorbic acid.

As the (d) skin care active ingredient, mention may be made of resorcinol derivatives.

The resorcinol derivative may preferably be 4-position substituted derivatives, such as 4- alkylresorcinols, more preferably phenyl ethyl resorcinol, 4-n-butylresorcinol and 4-(tetrahydro- 2H-pyran-4-yl) benzene- 1 ,3-diol, and in particular phenyl ethyl resorcinol because of its whitening effect. Phenyl ethyl resorcinol is also referred to as 4-( 1 -phenylethyl)- 1 ,3 -benzenediol and represented by the following chemical formula. Phenyl ethyl resorcinol can be obtained, for example, from Symrise Corp (the product name: Symwhite 377®).

As other examples of resorcinol derivatives, mention may be made of: 2-methylresorcinol, 5- methylresorcinol, 4-methylresorcinol, 4-ethylresorcinol, 2,5-dimethylresorcinol, 4,5- dimethylresorcinol, 2, 4-dimethyl- 1,3 -benzenediol, 3,5-dihydroxybenzylamine, 5- methoxyresorcinol, 3, 5 -dihydroxybenzyl alcohol, 2-methoxyresorcinol, 4-methoxyresorcinol, 3,5- dihydroxytoluene monohydrate, 4-chlororesorcinol, 2-chlororesorcinol, 2 ’,4’- dihydroxyacetophenone, 3 ’,5 ’-dihydroxyacetophenone, 2,6-dihydroxy-4-methylbenzaldehyde, 4- propylresorcinol, 2,4-dihydroxy-l,3,5-trimethylbenzene, 3,5-dihydroxybenzamide, 2,6- dihydroxybenzamide, 2,4-dihydroxybenzamide, 2,4-dihydroxybenzoic acid, 2,6- dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, 2,6-dihydroxy-4-methylbenzyl alcohol, 3,5- dihydroxyanisole hydrate, 4-aminoresorcinol hydrochloride, 2-aminoresorcinol hydrochloride, 5- aminobenzene-l,3-diol hydrochloride, 2 ’,4 ’-dihydroxypropiophenone, 2’,4’-dihydroxy-3’- methylacetophenone, (2,4-dihydroxyphenyl)acetone, (3,5-dihydroxyphenyl)acetone, 2,6- dihydroxy-4’ -methylacetophenone, 4-n-butylresorcinol, 2, 4-diethyl- 1,3 -benzenediol, 3,5- dihydroxy-4-methylbenzoic acid, 2,6-dihydroxy-4-methylbenzoic acid, 2,4-dihydroxy-6- methylbenzoic acid, 3,5-dihydroxyphenylacetic acid, 2-ethyl-5-methoxybenzene- 1,3 -diol, 4- amino-3,5-dihydroxybenzoic acid, 3, 5 -dihydroxyacetophenone monohydrate, 3,5- dihydroxybenzylamine hydrochloride, 4,6-dichlororesorcinol, 2 ’,4’ -dihydroxy-3 ’- methylpropiophenone, 1 -(3 -ethyl-2,6-dihydroxyphenyl)ethan- 1 -one, 2 ’ ,6 ’ -dihydroxy-4 ’ - methoxyacetophenone, 1 -(2,6-dihydroxy-3 -methoxyphenyl)ethan- 1 -one, 3 (2,4- dihydroxyphenylpropionic acid, and 2,4-dihydroxy-3,6-dimethylbenzoic acid.

As the (d) skin care active ingredient, mention may be made of C-glycoside derivatives.

The C-glycoside derivative(s) that may be present in the composition in accordance with the present invention can be chosen from the compounds of general formula (II) below:

in which:

R denotes an unsubstituted linear C₁-C₄ and especially C₁-C₂ alkyl radical, in particular methyl;

S represents a monosaccharide chosen from D-glucose, D-xylose, N-acetyl-D-glucosamine and L- fucose, and in particular D-xylose; and

X represents a group chosen from -CO-, -CH(OH)- and -CH(NH₂)- and preferentially a -CH(OH)- group, and also the cosmetically acceptable salts thereof, solvates thereof such as hydrates, and optical isomers thereof.

As nonlimiting illustrations of C-glycoside derivatives that are more particularly suitable for use in the present invention, mention may be made especially of the following derivatives: C-beta-D-xylopyranoside-n-propan-2-one;

C-alpha-D-xylopyranoside-n-propan-2-one;

C-beta-D-xylopyranoside-2-hydroxypropane;

C-alpha-D-xylopyranoside-2-hydroxypropane; 1-(C-beta-D-glucopyranosyl)-2 -hydroxypropane; 1-(C-alpha-D-glucopyranosyl)-2-hydroxpropane; 1-(C-beta-D-glucopyranosyl)-2-aminopropane;

1 -(C-alpha-D-glucopyranosyl)-2 -aminopropane;

3'-(acetamido-C-beta-D-glucopyranosyl)propan-2'-one;

3'-(acetaniido-C-alpha-D-glucopyranosyl)propan-2'-one; 1-(acetamido-C-beta-D-glucopyranosyl)-2-hydroxpropane; 1-(acetamido-C-beta-D-glucopyranosyl)-2-aminopropane; and also the cosmetically acceptable salts thereof, solvates thereof such as hydrates, and optical isomers thereof.

According to a particular embodiment, C-beta-D-xylopyranoside-2 -hydroxypropane or C-alpha- D-xylopyranoside-2-hydroxypropane, and better still C-beta-D-xylopyranoside-2- hydroxypropane, may be advantageously used for the preparation of the composition according to the present invention.

According to a particular embodiment, a C-glycoside derivative that is suitable for use in the present invention may advantageously be hydroxypropyltetrahydropyrantriol, also known as C- beta-D-xylopyranoside-2-hydroxpropane, sold especially as a solution at 30% by weight in a water/propylene glycol mixture (60/40) under the name Mexoryl SBB® by Chimex. According to one embodiment, the C-glycoside derivative is in the form of a solution in which it is present in an amount of 30% by weight relative to the total weight of the solution, the remainder being a mixture of water and propylene glycol.

The salts of the C-glycoside derivatives that are suitable for use in the present invention may comprise conventional physiologically acceptable salts of these compounds, such as those formed from organic or mineral acids. Examples that may be mentioned include the salts of mineral acids, such as sulfuric acid, hydrochloric acid, hydrobromic acid, hydroiodic acid, phosphoric acid and boric acid. Mention may also be made of the salts of organic acids, which may comprise one or more carboxylic, sulfonic or phosphonic acid groups. They may be linear, branched or cyclic aliphatic acids, or alternatively aromatic acids. These acids may also comprise one or more heteroatoms chosen from 0 and N, for example in the form of hydroxyl groups. Mention may be made especially of propionic acid, acetic acid, terephthalic acid, citric acid and tartaric acid.

The solvates that are acceptable for the compounds described above comprise conventional solvates such as those formed during the final step of preparation of said compounds due to the presence of solvents. Examples that may be mentioned include solvates due to the presence of water or of linear or branched alcohols, such as ethanol or isopropanol.

A C-glycoside derivative that is suitable for use in the present invention may especially be obtained via the synthetic method described in document WO 02/051 828, the content of which is incorporated herein by reference.

As the (d) skin care active ingredient, mention may be made of salicylic acid and derivatives thereof. The derivatives of salicylic acid may be represented by the formula (III):

wherein the radical R denotes a linear, branched or cyclic, saturated aliphatic chain containing from 2 to 22 carbon atoms; an unsaturated chain containing from 2 to 22 carbon atoms containing one or more double bonds that may be conjugated; an aromatic nucleus linked to the carbonyl radical directly or via saturated or unsaturated aliphatic chains containing from 2 to 7 carbon atoms; said groups possibly being substituted with one or more substituents, which may be identical or different, chosen from (a) halogen atoms, (b) the trifluoromethyl group, (c) hydroxyl groups in free form or esterified with an acid containing from 1 to 6 carbon atoms, or (d) a carboxyl function in free form or esterified with a lower alcohol containing from 1 to 6 carbon atoms; and

R' is a hydroxyl group. The salicylic acid derivative may be in the form of a salt derived from an inorganic or organic base.

The (d) skin active agent may be selected from a-hydroxy acids.

The term “a-hydroxy acid”, or “AHA”, here means a carboxylic acid which has at least one hydroxyl group on the adjacent (alpha) carbon atom.

The a-hydroxy acid can function as a skin peeling agent. It may be preferable to use a-hydroxy acid which can function as a soft skin peeling agent.

The a-hydroxy acid may be selected from, for example glycolic acid, lactic acid, malic acid, citric acid, tartaric acid, mandelic acid and gluconic acid and mixtures thereof, preferably from lactic acid, glycolic acid, and citric acid and mixtures thereof, more preferably be lactic acid.

It is preferable that the (d) skincare active agent be selected from the group consisting of lactic acid, niacinamide and mixtures thereof.

The amount of the (d) skincare active agent 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.

On the other hand, the amount of the (d) skincare active agent in the composition according to the present invention may be 25% by weight or less, preferably 20% by weight or less, and more preferably 15% by weight or less, relative to the total weight of the composition.

The amount of (d) skincare active agent in the composition according to the present invention may range from 0.01% to 25% by weight, preferably from 0.05% to 20% by weight, more preferably from 0.1 % to 15% by weight, relative to the total weight of the composition.

If the (d) skincare active agent is lactic acid, the amount thereof may be from 0.1% to 10% by weight, preferably from 0.2% to 9.5% by weight, and more preferably from 0.3% to 9% by weight, relative to the total weight of the composition.

If the (d) skincare active agent is niacinamide, the amount thereof may be from 0.1% to 20% by weight, preferably from 0.3% to 18% by weight, and more preferably from 0.5% to 15% by weight, relative to the total weight of the composition.

[Water]

The composition according to the present invention comprises (e) water.

The (e) water can form an aqueous phase which is a continuous phase of the composition according to the present invention, with or without any other possible hydrophilic ingredient(s) in the composition.

The amount of the (e) water in the composition according to the present invention may be 60% by weight or more, preferably 65% by weight or more, and more preferably 70% by weight or more, relative to the total weight of the composition.

On the other hand, the amount of the (e) 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.

The amount of (e) water in the composition according to the present invention may range from 60% to 95% by weight, preferably from 65% to 90% by weight, more preferably from 70% to 85% by weight, relative to the total weight of the composition.

[Polyol]

The composition according to the present invention may further 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.

The polyol may be a C₂-C ₁₂ polyol, preferably a C₂-C₉ polyol, comprising at least 2 hydroxy groups, and preferably 2 to 5 hydroxy groups.

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

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

The amount of the polyol(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.

On the other hand, the amount of the polyol(s) in the composition according to the present invention may be 25% by weight or less, preferably 20% by weight or less, and more preferably 15% by weight or less, relative to the total weight of the composition.

Thus, the polyol(s) may be present in the composition according to the present invention in an amount ranging from 0.01% to 25% by weight, and preferably from 0.05% to 20% by weight, such as from 0.1 % to 15% by weight, relative to the total weight of the composition.

[Other Ingredients]

The composition according to the present invention may contain one or more monoalcohols which are in the form of a liquid at room temperature (25 °C), such as for example linear or branched monoalcohols comprising from 1 to 6 carbon atoms, such as ethanol, propanol, butanol, isopropanol, isobutanol, pentanol, and hexanol.

The amount of the monoalcohol(s) in the composition according to the present invention may be 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.

On the other hand, the amount of the monoalcohol(s) in the composition according to the present invention may be 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.

Thus, the amount of the monoalcohol(s) in the composition according to the present invention may range 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.

The composition according to the present invention may also include various adjuvants conventionally used in cosmetic and dermatological compositions, such as anionic, non-ionic, cationic, and amphoteric or zwitterionic polymers; anionic, non-ionic, cationic, and amphoteric surfactants; thickeners; antioxidants; coloring agents; chelating agents; sequestering agents; fragrances; dispersing agents; conditioning agents; film-forming agents; preservatives; co-preservatives; and mixtures thereof, except for the ingredients as explained above.

The composition according to the present invention is free from anionic surfactant. The term “free from” here means that the composition according to the present invention may comprise anionic surfactant(s), but the amount of the anionic surfactant(s) is very limited such that it is 0.1% by weight or less, preferably 0.01% by weight or less, and more preferably 0.001% by weight or less, relative to the total weight of the composition. It is most preferable that the composition according to the present invention comprises no anionic surfactant.

In one embodiment, the composition according to the present invention may be free from polyoxyethylene-based nonionic surfactant. The term “free from” here means that the composition according to the present invention may comprise polyoxyethylene-based nonionic surfactant, but the amount of the polyoxyethylene-based nonionic surfactant is very limited such that it is 1% by weight or less, preferably less than 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 most preferable that the composition according to the present invention comprises no polyoxyethylene-based nonionic surfactant.

(Preparation)

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.

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.

[Form]

The composition according to the present invention is in the form of a nano- or micro-emulsion.

The "micro-emulsion" may be defined in two ways, namely, in a broad sense and in a narrow sense. That is to say, there is the one case ("micro-emulsion in the narrow sense") in which the micro-emulsion refers to a thermodynamically stable isotropic single liquid phase containing a ternary system having three ingredients of an oily component, an aqueous component and a surfactant, and there is the second case ("micro-emulsion in the broad sense") in which among thermodynamically unstable typical emulsion systems the micro-emulsion additionally includes those such emulsions presenting transparent or translucent appearances due to their smaller particle sizes (Satoshi Tomomasa, et al., Oil Chemistry, Vol. 37, No. 11 (1988), pp. 48-53). The "micro-emulsion" as used herein refers to a "micro-emulsion in the narrow sense", i.e., a thermodynamically stable isotropic single liquid phase.

The micro-emulsion refers to either one state of an O/W (oil-in-water) type microemulsion in which oil is solubilized by micelles, a W/O (water-in-oil) type microemulsion in which water is solubilized by reverse micelles, or a bicontinuous microemulsion in which the number of associations of surfactant molecules are rendered infinite so that both the aqueous phase and oil phase have a continuous structure.

The micro-emulsion may have a dispersed phase with a particle size of 100 nm or less, preferably 50 nm or less, and more preferably 20 nm or less, measured by laser granulometry.

The “nano-emulsion” here means an emulsion characterized by a dispersed phase with a size of less than 350 nm, the dispersed phase being stabilized by a crown of the (b) to (d) nonionic surfactants that may optionally form a liquid crystal phase of lamellar type, at the dispersed phase/continuous phase interface. In the absence of specific opacifiers, the transparency of the nano-emulsions arises from the small size of the dispersed phase, this small size being obtained by virtue of the use of mechanical energy.

Nanoemulsions can be distinguished from microemulsions by their structure. Specifically, micro-emulsions are thermodynamically stable dispersions formed from, for example, micelles which are formed by the ingredients (b) and (c) and swollen with the ingredient (a).

Furthermore, microemulsions do not require substantial mechanical energy in order to be prepared.

The nano-emulsion may have a dispersed phase with a particle size of 300 nm or less, preferably 200 nm or less, and more preferably 100 nm or less, measured by laser granulometry.

It is preferable that the composition according to the present invention be in the form of an O/W emulsion which comprises oil phases dispersed in a continuous aqueous phase. The dispersed oil phases can be oil droplets in the aqueous phase.

The O/W architecture or structure, which consists of oil phases dispersed in an aqueous phase, has an external aqueous phase, and therefore if the composition according to the present invention has the O/W architecture or structure, it can provide a pleasant feeling during use because of the feeling of immediate freshness that the aqueous phase can provide.

It is even more preferable that the particle size of the (a) oil be 300 nm or less, preferably 200 nm or less, more preferably 100 nm or less, and even more preferably 50 nm or less. The particle size can be measured by a dynamic light scattering method. The particle size measurement can be performed by, for example, the Particle Size Analyzer ELSZ-2000 series, marketed by Otsuka Electronics Co., Ltd.

The particle size can be a volume-average particle diameter or a number-average particle diameter, preferably a volume-average particle diameter.

The composition according to the present invention can be transparent or slightly translucent.

The transparency may be measured by measuring the turbidity (for example, turbidity can be measured with a 2100Q (marketed by Hach Company) having a round cell (25 mm in diameter and 60 mm height) and a tungsten filament lamp which can emit visible light (between 400 and 800 nm, preferably from 400 to 500 nm). The measurement can be performed on the undiluted composition. The blank may be determined with distilled water.

The composition according to the present invention has a turbidity of 300 NTU or less, preferably 200 NTU or less, more preferably 100 NTU or less, and even more preferably 50 NTU or less.

[Use and Process]

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

The composition according to the present invention can be used for a non-therapeutic process, such as a cosmetic process, for treating a keratin substance such as skin, hair, mucous membranes, nails, eyelashes, eyebrows and/or scalp, by being applied to the keratin substance. Thus, 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.

The present invention may also relate to a use of the composition according to the present invention as a cosmetic product or in a cosmetic product such as care products for body and/or facial skin and/or mucous membranes and/or the scalp and/or the hair and/or the nails and/or the eyelashes and/or the eyebrows.

In other words, the composition according to the present invention can be used, as it is, as a cosmetic product. Alternatively, the composition according to the present invention can be used as an element of a cosmetic product. For example the composition according to the present invention can be added to or combined with any other elements to form a cosmetic product.

The care product may be a lotion, a serum and the like.

EXAMPLES

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.

[Example 1 and Comparative Examples 1 and 2]

The following compositions according to Example 1 and Comparative Examples 1-2, shown in Table 1 , were prepared by mixing the components shown in Table 1 as follows.

The compositions according to Example 1 and Comparative Examples 1-2 were in the form of an O/W emulsion.

The numerical values for the amounts of the components shown in Table 1 are all based on “% by weight” as raw materials.

Table 1

NT: Not Tested

[Evaluations]

(Turbidity)

The turbidity of the compositions according to Example 1 and Comparative Examples 1-2 was measured at room temperature by using a turbidimeter (2100Q portable, Hach Company).

The results are shown in Table 1 as “NTU”. The smaller the NTU value is, the more transparent the composition is.

(Particle Size)

The particle size (nm) of the oil droplets in the compositions according to Example 1 and Comparative Example 2 was measured by the Particle Size Analyzer ELSZ-2000ZS (Otsuka Electronics Co., Ltd.).

The results are shown in Table 1.

The particle size of the oil droplets in the composition according to Comparative Example 1 was not measured because it was opaque and clearly not in the form of a nano- or micro-emulsion. Comparative Example 2 corresponds to Example 1 of WO 2020/110716.

Comparative Example 1 shows that the addition of lactic acid and niacinamide to the composition according to Comparative Example 2 prevents the formation of a nano- or micro-emulsion.

Example 1 shows that the use of a combination of the two different types of polyglyceryl fatty acid esters with a weight ratio of the amount of the polyglyceryl fatty acid ester with a higher E1LB value (the first polyglyceryl fatty acid ester)/the amount of the polyglyceryl fatty acid ester with a lower HLB value (the second polyglyceryl fatty acid ester) (cf. “High HLB PG Surfactant/Low HLB PG Surfactant” in Table 1) being 3.0 or more under the presence of no anionic surfactant can form a nano- or micro-emulsion.

[Examples 2-1 to 2-7]

The following compositions according to Examples 2-1 to 2-7, shown in Table 2, were prepared by mixing the components shown in Table 2 as follows.

The compositions according to Examples 2-1 to 2-7 were in the form of an O/W emulsion.

The numerical values for the amounts of the components shown in Table 2 are all based on “% by weight” as raw materials.

[Evaluations]

(Turbidity)

The turbidity of the compositions according to Examples 2-1 to 2-7 was measured at room temperature by using a turbidimeter (2100Q portable, Hach Company).

The results are shown in Table 2 as “NTU”. The smaller the NTU value is, the more transparent the composition is.

(Particle Size)

The particle size (nm) of the oil droplets in the compositions according to Examples 2-1 to 2-7 was measured by the Particle Size Analyzer ELSZ-2000ZS (Otsuka Electronics Co., Ltd.).

The results are shown in Table 2.

Examples 2-1 to 2-7 show that, at least, the use of the first and second polyglyceryl fatty acid esters in a total amount of from 0.05% by weight or more (cf. “Surfactants (%)” in Table 2), relative to the total weight of the composition, can work to prepare a nano- or micro-emulsion.

[Examples 3-1 to 3-5 and Comparative Examples 3-1 to 3-6]

The following compositions according to Examples 3-1 to 3-5 and Comparative Examples 3-1 to 3-6, shown in Table 3, were prepared by mixing the components shown in Table 3 as follows.

The compositions according to Examples 3-1 to 3-5 and Comparative Examples 3-1 to 3-6 were in the form of an O/W emulsion.

The numerical values for the amounts of the components shown in Table 3 are all based on “% by weight” as raw materials.

[Evaluations]

(Turbidity)

The turbidity of the compositions according to Examples 3-1 to 3-5 and Comparative Examples 3- 1 to 3-6 was measured at room temperature by using a turbidimeter (2100Q portable, Hach Company).

The results are shown in Table 3 as “NTU”. The smaller the NTU value is, the more transparent the composition is.

(Particle Size)

The particle size (nm) of the oil droplets in the compositions according to Examples 3-1 to 3-5 was measured by the Particle Size Analyzer ELSZ-2000ZS (Otsuka Electronics Co., Ltd.).

The results are shown in Table 3.

The particle size of the oil droplets in the compositions according to Comparative Examples 3-1 to 3-6 was not measured because they were opaque and clearly not in the form of a nano- or microemulsion.

Examples 3-1 to 3-5 show that when the weight ratio of the amount of oiVthe total amount of the first and second polyglyceryl fatty acid esters (cf. Weight Ratio of OiVSurfactanf’ in Table 3) is 0.5 or less, a nano- or micro-emulsion can be prepared.

Comparative Examples 3-1 to 3-6 show that when the weight ratio of the amount of oiVthe total amount of the first and second polyglyceryl fatty acid esters (cf. Weight Ratio of OiVSurfactanf ’ in Table 3) is more than 0.5, a nano- or micro-emulsion cannot be prepared.

[Examples 4-1 to 4-4 and Comparative Examples 4-1 to 4-6]

The following compositions according to Examples 4-1 to 4-4 and Comparative Examples 4-1 to 4-6, shown in Table 4, were prepared by mixing the components shown in Table 4 as follows.

The compositions according to Examples 4-1 to 4-4 and Comparative Examples 4-1 to 4-6 were in the form of an O/W emulsion.

The numerical values for the amounts of the components shown in Table 4 are all based on “% by weight” as raw materials.

[Evaluations]

(Turbidity)

The turbidity of the compositions according to Examples 4-1 to 4-4 and Comparative Examples 4- 1 to 4-6 was measured at room temperature by using a turbidimeter (2100Q portable, Hach Company).

The results are shown in Table 4 as “NTU”. The smaller the NTU value is, the more transparent the composition is.

(Particle Size)

The particle size (nm) of the oil droplets in the compositions according to Examples 4-1 to 4-4 was measured by the Particle Size Analyzer ELSZ-2000ZS (Otsuka Electronics Co., Ltd.).

The results are shown in Table 4.

The particle size of the oil droplets in the compositions according to Comparative Examples 4-1 to 4-6 was not measured because they were opaque and clearly not in the form of a nano- or microemulsion.

Examples 4-1 to 4-4 show that when the weight ratio of the amount of the first polyglyceryl fatty acid ester/the amount of the second polyglyceryl fatty acid ester (cf. “High HLB PG Surfactant/Low HLB PG Surfactant” in Table 4) is 3.0 or more, a nano- or micro-emulsion can be prepared.

Comparative Examples 4-1 to 4-4 show that when the weight ratio of the amount of the first polyglyceryl fatty acid ester/the amount of the second polyglyceryl fatty acid ester (cf. “High HLB PG Surfactant/Low HLB PG Surfactant” in Table 4) is less than 3.0, a nano- or micro-emulsion cannot be prepared.

[Examples 5-1 to 5-11]

The following compositions according to Examples 5-1 to 5-11, shown in Table 5, were prepared by mixing the components shown in Table 5 as follows.

The compositions according to Examples 5-1 to 5-11 were in the form of an O/W emulsion.

The numerical values for the amounts of the components shown in Table 5 are all based on “% by weight” as raw materials.

[Evaluations]

(Turbidity)

The turbidity of the compositions according to Examples 5-1 to 5-11 was measured at room temperature by using a turbidimeter (2100Q portable, Hach Company).

The results are shown in Table 5 as “NTU”. The smaller the NTU value is, the more transparent the composition is.

(Particle Size)

The particle size (nm) of the oil droplets in the compositions according to Examples 5-1 to 5-11 was measured by the Particle Size Analyzer ELSZ-2000ZS (Otsuka Electronics Co., Ltd.).

The results are shown in Table 5.

Examples 5-1 to 5-9 show that, at least, the use of lactic acid in an amount of from 0.1% to 10% by weight and the use of niacinamide in an amount of 0.1% to 20% by weight can work to prepare a nano- or micro-emulsion can be prepared.

Examples 5-10 and 5-11 show that each of lactic acid and niacinamide can be used alone.

[Examples 6-1 to 6-10]

The following compositions according to Examples 6-1 to 6-10, shown in Table 6, were prepared by mixing the components shown in Table 6 as follows.

The compositions according to Examples 6-1 to 6-10 were in the form of an O/W emulsion.

The numerical values for the amounts of the components shown in Table 6 are all based on “% by weight” as raw materials.

[Evaluations]

(Turbidity)

The turbidity of the compositions according to Examples 6-1 to 6-11 was measured at room temperature by using a turbidimeter (2100Q portable, Hach Company).

The results are shown in Table 6 as “NTU”. The smaller the NTU value is, the more transparent the composition is.

(Particle Size)

The particle size (nm) of the oil droplets in the compositions according to Examples 6-1 to 6-10 was measured by the Particle Size Analyzer ELSZ-2000ZS (Otsuka Electronics Co., Ltd.).

The results are shown in Table 6.

Examples 6-1 to 6-10 show that, a nano- or micro-emulsion can be prepared under, at least, the pH of from 3.5 to 9.0.

Claims

1. A composition in the form of a nano- or micro-emulsion, comprising:

(a) at least one optional oil;

(b) at least one first polyglyceryl fatty acid ester having an HLB value of 13.0 or more, preferably 13.5 or more, and more preferably 14.0 or more;

(d) at least one skincare active agent; and

(e) water, wherein the weight ratio of the amount of the (b) first polyglyceryl fatty acid ester/the amount of the (c) second polyglyceryl fatty acid ester is 3.0 or more, preferably 4.0 or more, and even more preferably 5.0 or more, the weight ratio of the amount of the (a) oil/the total amount of the (b) first polyglyceryl fatty acid ester and the (c) second polyglyceryl fatty acid ester is 0.5 or less, and the composition comprises 0.1% by weight or less of anionic surfactant(s), preferably 0.01% by weight or less of anionic surfactant(s), and more preferably no anionic surfactant.

2. The composition according to Claim 1 , wherein the composition has a turbidity of 300 NTU or less, preferably 200 NTU or less, and more preferably 100 NTU or less.

3. The composition according to Claim 1 or 2, wherein the (a) oil is selected from polar oils.

4. The composition according to any one of Claims 1 to 3, wherein the amount of the (a) oil(s) in the composition ranges from 10% by weight or less, preferably 5% by weight or less, and more preferably from 1% by weight or less, relative to the total weight of the composition.

5. The composition according to any one of Claims 1 to 4, wherein the (b) first polyglyceryl fatty acid ester comprises 2 to 4 glycerol units, preferably 3 or 4 glycerol units, and more preferably 4 glycerol units.

6. The composition according to any one of Claims 1 to 5, wherein the fatty acid moiety of the

(b) first polyglyceryl fatty acid ester comprises 12 or fewer carbon atoms, preferably 11 or fewer carbon atoms, and more preferably 10 or fewer carbon atoms.

7. The composition according to any one of Claims 1 to 6, wherein the (c) second polyglyceiyl fatty acid ester comprises 2 to 4 glycerol units, preferably 2 or 3 glycerol units, and more preferably 2 glycerol units.

8. The composition according to any one of Claims 1 to 7, wherein the fatty acid moiety of the

(c) second polyglyceiyl fatty acid ester comprises 14 or more carbon atoms, preferably 16 or more carbon atoms, and more preferably 18 or more carbon atoms.

9. The composition according to any one of Claims 1 to 8, wherein the total amount of the (b) first polyglyceryl fatty acid ester and the (c) second polyglyceiyl fatty acid ester is 0.05% by weight or more, preferably 0.1% weight or more, and more preferably 1% by weight or more of the composition.

10. The composition according to any one of Claims 1 to 9, wherein the (d) skincare active agent is selected from the group consisting of lactic acid, niacinamide and mixtures thereof.

11. The composition according to any one of Claims 1 to 10, wherein the amount of the (d) skincare active agent is from 0.01% to 25% by weight, preferably from 0.05% to 20% by weight, and more preferably from 0.1 % to 15% by weight, relative to the total weight of the composition.

12. The composition according to any one of Claims 1 to 11 , wherein the pH of the composition is from 3.5 to 9.0, preferably from 4.0 to 8.0, more preferably from 4.5 to 7.0, and even more preferably from 4.0 to 6.0.

13. The composition according to any one of Claims 1 to 12, wherein the composition is in the form of a nano- or micro- O/W emulsion.

14. The composition according to Claim 13, wherein the particle size of the (a) oil is 300 nm or less, preferably 200 nm or less, and more preferably 100 nm or less.

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.