WO2014098263A1

WO2014098263A1 - Cosmetic composition comprising oil, non ionic surfactant and vitamine b3

Info

Publication number: WO2014098263A1
Application number: PCT/JP2013/085300
Authority: WO
Inventors: Anne-Laure Bernard; Veronique Chevalier; Yuichi Ikeda
Original assignee: L'oreal
Priority date: 2012-12-21
Filing date: 2013-12-20
Publication date: 2014-06-26
Also published as: JP2014122193A

Abstract

The present invention relates to a cosmetic composition in the form of a nano- or micro-emulsion, comprising: (a) at least one oil; (b) at least one nonionic surfactant with an HLB value of from 8.0 to 14, preferably from 9.0 to 13.5, and more preferably from 10.0 to 13; (c) at least one compound selected from Vitamin B3 and derivatives thereof; and (d) water. The cosmetic composition according to the present invention has a dispersed phase which has a smaller diameter due to the presence of at least one compound selected from Vitamin B3 and derivatives thereof. Therefore, the cosmetic composition can be in the form of a nano- or micro-emulsion with transparent or slightly translucent.

Description

DESCRIPTION

COSMETIC COMPOSITION COMPRISING OIL, NON IONIC SURFACTANT AND

VITAMINE B3

TECHNICAL FIELD

The present invention relates to a cosmetic composition in the form of a nano- or micro-emulsion. 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 or toilet waters.

It is known practice, in the cosmetics or dermatological field, to use oil-in-water (O/W) emulsions. These emulsions, that consist of an oil phase (or lipophilic phase) dispersed in an aqueous phase, have an external aqueous phase and are therefore products that are more pleasant to use because of the feeling of f eshness that they provide. However, they have the drawback of relatively lacking stability when the amount of oil present is too great. Now, for some applications, it is

advantageous to have a large amount of oils since the oils provide comfort for the skin, nourish it, and can also remove makeup from it when these oils have makeup-removing properties.

Moreover, it is advantageous to have fine emulsions, i.e. emulsions where the oily phase is in the form of very small droplets, i.e. of droplets less than 4 μιη in size, since these fine emulsions have a pleasant cosmetic feel and are generally more stable than coarse emulsions.

These emulsions can be prepared in particular by the phase inversion temperature technique (PIT emulsions), in which the average size of the globules constituting the oily phase is wilhin given limits, namely between 0.1 and 4 μηι (100 to 4000 nm). The principle of phase inversion temperature (or PIT) emulsification is, in theoretical terms, well known to those skilled in the art; it was described in 1968 by K. Shinoda (J. Chem. Soc. Jpn., 1968, 89, 435). It was shown that this emulsification technique makes it possible to obtain stable fine emulsions (K. Shinoda and H.

Saito, J. Colloid Interface Sci., 1969, 30, 258). This technology was applied in cosmetics as early as 1972 by Mitsui et al. ("Application of the phase-inversion-temperature method to the emulsification of cosmetics"; T. Mitsui, Y. Machida and F. Harusawa, American. Cosmet. Perfum.,

1972, 87,33).

The principle of this technique is as follows: an O W emulsion (introduction of the aqueous phase into the oily phase) is prepared at a temperature that should be greater than the phase inversion temperature of the system, i.e. the temperature at which the equilibrium between the hydrophilic and lipophilic properties of the emulsifier(s) used is attained; at higher temperature, i.e. greater than the phase inversion temperature (> PIT), the emulsion is of water-in-oil type and, as it cools, this emulsion inverts at the phase inversion temperature so as to become an emulsion of oil-in-water type, having beforehand passed through a state of microemulsion. This process makes it possible to readily obtain emulsions with a diameter generally less than 4 μπι.

Emulsifying surfactants of the oil-in- water type conventionally used have an HLB (HLB = hydrophilic lipophilic balance) ranging from 8 to 18. These emulsifiers, due to their amphiphilic structure, are situated at the oil phase/aqueous phase interface, and thus stabilize the dispersed oil droplets.

However, it is difficult to produce fine O W emulsions containing a large amount of oily phase, since such emulsions have a tendency to destabilize, this destabilization resulting in coalescence and separation of the aqueous and oily phases with release of the oil. In order to improve the stability of these emulsions, the concentration of emulsifiers can be increased; however, a high concentration of emulsifiers can result in a rough, clingy or sticky feel, and in problems of innocuity with respect to the skin, the eyes and the scalp.

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.

For example, JP-A-H09- 110635 discloses a fine emulsion which is formed by using a

combination of polyglyceryl fatty acid ester, as a surfactant, and C₁₀-C 222-hydroxy fatty acid. In addition, JP-A-H11-71256 discloses a fine emulsion which is formed by using a combination of polyglyceryl fatty acid ester and a betain.

DISCLOSURE OF INVENTION

However, when a certain type of a nonionic surfactant is used for preparing a fine emulsion such as a nano- or micro-emulsion, the transparent or slightly translucent aspect of the emulsion as well as stability of the emulsion, are impaired.

An objective of the present invention is to provide a stable cosmetic composition in the form of a nano- or micro-emulsion with improved transparent or slightly translucent, preferably transparent, aspect of the emulsion, even when the above nonionic surfactant is used.

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

(a) at least one oil;

(b) at least one nonionic surfactant with an HLB value of from 8.0 to 14, preferably from 9.0 to 13.5, and more preferably from 10.0 to 13;

(c) at least one compound selected from Vitamin B3 and derivatives thereof; and

(d) water. The (a) oil may be selected from the group consisting of oils of plant or animal origin, synthetic oils, silicone oils and hydrocarbon oils. Preferably, the (a) oil may be chosen from hydrocarbon oils which are in the form of a liquid at a room temperature. It may be preferable that the (a) oil be chosen from oils with molecular weight below 600 g/mol.

The amount of the (a) oil may range from 0.1 to 50% by weight, preferably from 0.5 to 40% by weight, and more preferably from 3 to 30% by weight, relative to the total weight of the composition.

The (b) nonionic surfactant may be chosen from:

- surfactants that are fluid at a temperature of less than or equal to 45 °C, chosen from the esters of at least one polyol chosen from the group formed by polyethylene glycol comprising from 1 to 60 ethylene oxide units, sorbitan, glycerol comprising from 2 to 30 ethylene oxide units, poly glycerols comprising from 2 to 12 glycerol units, and of at least one fatty acid comprising at least one saturated or unsaturated, linear or branched C -C₂₂ alkyl chain,

mixed esters of fatty acid or of fatty alcohol, of carboxylic acid and of glycerol, fatty acid esters of sugars and fatty alcohol ethers of sugars,

surfactants that are solid at a temperature of less than or equal to 45 °C, chosen from fatty esters of glycerol, fatty esters of sorbitan and oxyethylenated fatty esters of sorbitan, ethoxylated fatty ethers and ethoxylated fatty esters,

block copolymers of ethylene oxide (A) and of propylene oxide (B), and

silicone surfactants,

It is preferable that the (b) nonionic surfactant be chosen from:

- polyethylene glycol isostearate or oleate (8 to 10 mol of ethylene oxide),

polyethylene glycol isocetyl, behenyl ether or isostearyl ether (8 to 10 mol of ethylene oxide),

polyglyceryl monolaurate or dilaurate comprising 3 to 6 glycerol units,

polyglyceryl mono(iso)stearate comprising 3 to 6 glycerol units,

- polyglyceryl monooleate comprising 3 to 6 glycerol units, and

polyglyceryl dioleate comprising 3 to 6 glycerol units.

The (b) nonionic surfactant may be chosen from polyglyceryl fatty acid esters, preferably esters of a fatty acid and polyglycerine comprising 70% or more of polyglycerine whose polymerization degree is 4 or more, preferably esters of a fatty acid and polyglycerine containing equal to or more than 60% of polyglycerine whose polymerization degree is between 4 and 11 , and more preferably esters of a fatty acid and polyglycerine containing equal to or more than 30% of polyglycerine whose polymerization degree is 5. The amount of the (b) nonionic surfactant may range from 0.1 to 30% by weight, preferably from 1 to 25% by weight, and more preferably from 3 to 20% by weight, relative to the total weight of the composition.

The ratio of the (b) nonionic surfactant to the (a) oil may be from from 0.25 to 6, preferably from 0.3 to 3, and more preferably from 0.4 to 1.5.

The (c) compound may have a log P being from -0.7 to 6, preferably from -0.5 to 4, and more preferably from -0.3 to 2. It is preferable that the (c) compound be Vitamin B3, more preferably niacinnamide. The amount of the (c) compound may range from 0.01 to 20% by weight, preferably from 0.1 to 15% by weight, and more preferably from 1 to 10% by weight, relative to the total weight of the composition.

The cosmetic composition according to the present invention may further comprise at least one nonionic surfactant different from the above (b) and/or at least one ionic surfactant.

The cosmetic composition according to the present invention may further comprise at least one polyol.

The cosmetic composition according to the present invention may further comprise at least one thickening agent, preferably selected from associative thickeners. It is preferable that the cosmetic composition according to the present invention be in the form of an O/W emulsion, and the (a) oil be in the form of a droplet with a number average particle size of 300 nm or less, preferably from 10 nm to 150 nm.

It is preferable that the cosmetic composition according to the present invention have a

transparency greater than 50%, more preferably greater than 60%, and further more preferably greater than 70%.

Further, the present invention also relates to a non-therapeutic process for treating the skin, the hair, mucous membranes, the nails, the eyelashes, the eyebrows and/or the scalp, characterized in that the cosmetic composition according to the present invention is applied to the skin, the hair, mucous membranes, the nails, the eyelashes, the eyebrows or the scalp.

Furthermore, the present invention also relates to a use of the cosmetic composition according to the present invention, as or in care products and/or washing products and/or make-up products and/or make-up-removing 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.

BEST MODE FOR CARRYING OUT THE INVENTION After diligent research, the inventors have discovered that it is possible to provide a stable cosmetic composition in the form of a nano- or micro-emulsion with transparent or slightly translucent, preferably transparent, aspect of the emulsion, even when using a nonionic surfactant which was difficult to form a fine emulsion such as a nano- or micro-emulsion. Thus, the present invention is a cosmetic composition in the form of a nano- or micro-emulsion, comprising:

(a) at least one oil;

(c) at least one compound selected from Vitamin B3 and derivatives thereof; and (d) water.

The cosmetic composition according to the present invention has a dispersed phase which has a smaller diameter due to the presence of at least one compound selected from Vitamin B3 and derivatives thereof. Therefore, the cosmetic composition can be in the form of a nano- or micro-emulsion with transparent or slightly translucent.

Since the cosmetic composition according to the present invention can have transparent or slightly translucent, the composition can be preferably used for lotions and the like. Further, as the dispersed phase is finely dispersed, the cosmetic composition according to the present invention can provide unique texture, moisturizing and wet feeling, as well as increased suppleness.

Furthermore, if the dispersed phase is an oil phase and includes one or more lipophilic or even amphophilic active ingredients, the dispersed oil phase can function as a carrier of the active ingredient and accelerate the penetration of the active ingredients into the skin, or can distribute the active ingredients on the skin.

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

The cosmetic composition according to the present invention may comprise at least one oil.

Here, "oil" means a fatty compound or substance which is in the form of a liquid 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, preferably non- volatile.

The 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.

It is preferable that the (a) oil be selected from the group consisting of oils of plant or animal origin, synthetic oils, silicone oils and hydrocarbon oils.

As examples of plant oils, mention may be made of, for example, linseed oil, camellia oil, macadamia nut oil, corn 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, sqiialene 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 Ci-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 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 -C₂₂ alcohols and esters of monocarboxylic, dicarboxylic or tricarboxylic acids and of non-sugar C -C₂ 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 C -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, oleopalmitates, 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 caprylate/caprate, methyl palmitate, ethyl palmitate, isopropyl palmitate, 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, glyceryl trimyristate, glyceryl tripalrnitate, 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 octamethylcyclotetrasiloxane,

decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, and the like; and mixtures thereof.

Preferably, 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 comprising 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.

Volatile or non- volatile silicone oils, such as volatile or non- volatile polydimethylsiloxanes

(PDMS) containing a linear or cyclic silicone chain, that are liquid or pasty at ambient temperature, in particular cyclopolydimethylsiloxanes (cyclomethicones) such as cyclohexasiloxane;

polydimethylsiloxanes containing alkyl, alkoxy or phenyl groups that are pendent or at the end of the silicone chain, which groups have from 2 to 24 carbon atoms; phenyl silicones such as phenyl trimethicones, phenyl dimethicones, phenyltrimethylsiloxydiphenylsiloxanes, diphenyl dimethicones, diphenylmethyldiphenyltrisiloxanes, 2-phenylemyltrimethyl siloxysilicates, and polymethylphenylsiloxanes, may be used.

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 mineral oil(e.g., liquid paraffin), paraffin, vaseline or petrolatum, naphthalenes, and the like; hydrogenated polyisobutene, isoeicosan, and decene butene copolymer; and mixtures thereof.

It is preferable that the (a) oil be chosen from hydrocarbon oils which are in the form of a liquid at a room temperature.

It is also preferable that the (a) oil be chosen from oils with 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 chainsiQ-Cn) (e.g., isopropyl myristate, isopropyl palmitate, isononyl isononanoate, and ethyl hexyl palmitate), hydrocarbon oils (e.g., isododecane, isohexadecane, and squalane), branched and/or unsaturated fatty alcohol (C₁₂-C₃₀) type oils such as octyldodecanol, oleyl alcohol, ether oils such as dicaprylylether.

The amount in the cosmetic composition according to the present invention of the (a) oil is not limited, and may range from 0.1 to 50% by weight, preferably from 0.5 to 40% by weight, and more preferably from 5 to 30% by weight, relative to the total weight of the composition.

[Nonionic Surfactant]

The cosmetic composition according to the present invention may comprise at least one specific nonionic surfactant. A single type of the specific nonionic surfactant may be used, but two or more different types of the specific nonionic surfactant may be used in combination.

The nonionic surfactant has an HLB (Hydrophilic Lipophilic Balance) value of from 8.0 to 14, preferably from 9.0 to 13.5, and more preferably from 10.0 to 13. If two or more nonionic surfactants are used, the HLB value is determined by the weight average of the HLB values of all the nonionic surfactants.

The HLB is the ratio between the hydrophilic part and the lipophilic part in the molecule. This term HLB is well known to those skilled in the art and is described in "The HLB system. A time-saving guide to emulsifier selection" (published by ICI Americas Inc., 1984).

The term HLB ("hydrophilic-lipophilic balance") is well known to those skilled in the art, and denotes the hydrophilic-lipophilic balance of a surfactant. The HLB or hydrophilic-lipophilic balance of the surfactant(s) used according to the invention is the HLB according to Griffin, defined in the publication J Soc. Cosm. Chem., 1954 (Vol 5), pages 249-256 or the HLB determined experimentally and as described in the publication from the authors F. Puisieux and M. Seiller, entitled "Galenica 5: Les systemes disperses [Dispersed systems] - Volume I - Agents de surface et emulsions [Surface agents and emulsions] - Chapter TV - Notions de HLB et de HLB critique [Notions of HLB and of critical HLB], pages 153-194 - paragraph 1.1.2. Determination de HLB par voie experimentale [Experimental determination of HLB], pages 164-180.

It is preferably the calculated HLB values that should be taken into account.

The calculated HLB is defined as being the following coefficient:

calculated HLB = 20 * molar mass of the hydrophilic part total molar mass.

For an oxyethylenated fatty alcohol, the hydrophilic part corresponds to the oxyethylene units fused to the fatty alcohol and the calculated HLB then corresponds to the HLB according to Griffin (Griffin W.C., J. Soc. Cosmet. Chemists, 5, 249, 1954).

The (b) nonionic surfactant with an HLB value of from 8.0 to 14, preferably from 9.0 to 13.5, and more preferably from 10.0 to 13 may be chosen from:

(1) surfactants that are fluid at a temperature of less than or equal to 45°C, chosen from the esters of at least one polyol chosen from the group formed by polyethylene glycol comprising from 1 to 60 ethylene oxide units, sorbitan, glycerol comprising from 2 to 30 ethylene oxide units, polyglycerols comprising from 2 to 12 glycerol units, and of at least one fatty acid comprising at least one saturated or unsaturated, linear or branched Cg-C₂₂ alkyl chain,

(2) mixed esters of fatty acid or of fatty alcohol, of carboxylic acid and of glycerol,

(3) fatty acid esters of sugars and fatty alcohol ethers of sugars,

(4) surfactants that are solid at a temperature of less than or equal to 45 °C, chosen from fatty esters of glycerol, fatty esters of sorbitan and oxyethylenated fatty esters of sorbitan, ethoxylated fatty ethers and ethoxylated fatty esters,

(5) block copolymers of ethylene oxide (A) and of propylene oxide (B), and

(6) silicone surfactants.

The surfactants (1) that are fluid at a temperature of less than or equal to 45°C may be, in particular: the isostearate of polyethylene glycol of molecular weight 400, sold under the name PEG 400 by the company Unichema;

diglyceryl isostearate, sold by the company Solvay;

glyceryl laurate comprising 2 glycerol units, sold by the company Solvay;

- sorbitan oleate, sold under the name Span 80 by the company ICI;

sorbitan isostearate, sold under the name Nikkol SI 1 OR by the company Nikko; and oc-butylglucoside cocoate or a-butylglucoside caprate, sold by the company Ulice.

The (2) mixed esters of fatty acid or of fatty alcohol, of carboxylic acid and of glycerol, which can be used as the above nonionic surfactant, may be chosen in particular from the group comprising mixed esters of fatty acid or of fatty alcohol with an alkyl chain containing from 8 to 22 carbon atoms, and of -hydroxy acid and/or of succinic acid, with glycerol. The a-hydroxy acid may be, for example, citric acid, lactic acid, glycolic acid or malic acid, and mixtures thereof. The alkyl chain of the fatty acids or alcohols from which are derived the mixed esters which can be used in the nanoemulsion of the invention may be linear or branched, and saturated or unsaturated. They may especially be stearate, isostearate, linoleate, oleate, behenate,

arachidonate, palmitate, myristate, laurate, caprate, isostearyl, stearyl, linoleyl, oleyl, behenyl, myristyl, lauryl or capryl chains, and mixtures thereof.

As examples of mixed esters which can be used in the nanoemulsion of the invention, mention may be made of the mixed ester of glycerol and of the mixture of citric acid, lactic acid, linoleic acid and oleic acid (CTFA name: Glyceryl citrate/lactate/linoleate/oleate) sold by the company Hiils under the name Imwitor 375; the mixed ester of succinic acid and of isostearyl alcohol with glycerol (CTFA name: Isostearyl diglyceryl succinate) sold by the company Huls under the name Imwitor 780 K; the mixed ester of citric acid and of stearic acid with glycerol (CTFA name:

Glyceryl stearate citrate) sold by the company Hiils under the name Imwitor 370; the mixed ester of lactic acid and of stearic acid with glycerol (CTFAname: Glyceryl stearate lactate) sold by the company Danisco under the name Lactodan B30 or Rylo LA30.

The (3) fatty acid esters of sugars, which can be used as the above nonionic surfactant, may preferably be solid at a temperature of less than or equal to 45°C and may be chosen in particular from the group comprising esters or mixtures of esters of C₈-C₂₂ fatty acid and of sucrose, of maltose, of glucose or of fructose, and esters or mixtures of esters of C₁₄-C₂₂ fatty acid and of methylglucose.

The C₈-C₂₂ or C₁₄-C₂₂ fatty acids forming the fatty unit of the esters which can be used in the present invention comprise a saturated or unsaturated linear alkyl chain containing, respectively, from 8 to 22 or from 14 to 22 carbon atoms. The fatty unit of the esters may be chosen in particular from stearates, behenates, arachidonates, palmitates, myristates, laurates and caprates, and mixtures thereof. Stearates are preferably used.

As examples of esters or mixtures of esters of fatty acid and of sucrose, of maltose, of glucose or of fructose, mention may be made of sucrose monostearate, sucrose distearate and sucrose tristearate and mixtures thereof, such as the products sold by the company Croda under the name Crodesta F50, F70, F 110 and F 160; and examples of esters or mixtures of esters of fatty acid and of methylglucose which may be mentioned are methylglucose polyglyceryl-3 distearate, sold by the company Goldschmidt under the name Tego-care 450. Mention may also be made of glucose or maltose monoesters such as methyl o-hexadecanoyl-6-D-glucoside and

o-hexadecanoyl-6-D-maltoside.

The (3) fatty alcohol ethers of sugars, which can be used as the above nonionic surfactant, may be solid at a temperature of less than or equal to 45 °C and may be chosen in particular from the group comprising ethers or mixtures of ethers of C₈-C₂₂ fatty alcohol and of glucose, of maltose, of sucrose or of fructose, and ethers or mixtures of ethers of a C₁₄-C₂₂ fatty alcohol and of methylglucose. These are in particular alkylpolyglucosides.

The C₈-C₂₂ or C₁₄-C₂₂ fatty alcohols forming the fatty unit of the.ethers which may be used in the nanoemulsion of the invention comprise a saturated or unsaturated, linear alkyl chain containing, respectively, from 8 to 22 or from 14 to 22 carbon atoms. The fatty unit of the ethers may be chosen in particular from decyl, cetyl, behenyl, arachidyl, stearyl, palmityl, myristyl, lauryl, capryl and hexadecanoyl units, and mixtures thereof, such as cetearyl.

As examples of fatty alcohol ethers of sugars, mention may be made of alkylpolyglucosides such as decylglucoside and laurylglucoside, which is sold, for example, by the company Henkel under the respective names Plantaren 2000 and Plantaren 1200, cetostearyl glucoside optionally as a mixture with cetostearyl alcohol, sold for example, under the name Montanov 68 by the company SEPPIC, under the name Tego-care CG90 by the company Goldschmidt and under the name Emulgade KE3302 by the company Henkel, as well as arachidyl glucoside, for example in the form of a mixture of arachidyl alcohol and behenyl alcohol and arachidyl glucoside, sold under the name Montanov 202 by the company SEPPIC.

The surfactant used more particularly is sucrose monostearate, sucrose distearate or sucrose tristearate and mixtures thereof, methylglucose polyglyceryl-3 distearate and alkylpolyglucosides.

The (4) fatty esters of glycerol which may be used as the above nonionic surfactant, which are solid at a temperature of less than or equal to 45 °C, may be chosen in particular from the group comprising esters formed from at least one acid comprising a saturated linear alkyl chain containing from 12 to 22 carbon atoms and from 1 to 12 glycerol units. One or more of these fatty esters of glycerol may be used in the present invention.

These esters may be chosen in particular from stearates, behenates, arachidates and palmitates, and mixtures thereof. Stearates and palmitates are preferably used. As examples of surfactants which can be used in the present invention, mention may be made of decaglyceryl monostearate, distearate, tristearate and pentastearate (CTFAnames: Polyglyceryl-10 stearate, Polyglyceryl-10 distearate, Polyglyceryl-10 tristearate, Polyglyceryl-10 pentastearate), such as the products sold under the respective names Nikkol Decaglyn 1-S, 2-S, 3-S and 5-S by the company Nikko, and diglyceryl monostearate (CTFAname: Polyglyceryl-2 stearate), such as the product sold by the company Nikko under the name Nikkol DGMS. The (4) fatty esters of sorbitan which may be used as the above nonionic surfactant, which are solid at a temperature of less than or equal to 45°C, may be chosen from the group comprising C₁₆-C₂2 fatty acid esters of sorbitan and oxyethylenated C₁₆-C₂₂ fatty acid esters of sorbitan.

They are formed from at least one fatty acid comprising at least one saturated linear alkyl chain containing, respectively, from 16 to 22 carbon atoms, and from sorbitol or from ethoxylated sorbitol. The oxyethylenated esters generally comprise from 1 to 100 ethylene glycol units and preferably from 2 to 40 ethylene oxide (EO) units. These esters may be chosen in particular from stearates, behenates, arachidates, palmitates, and mixtures thereof. Stearates and palmitates are preferably used.

As examples of the above nonionic surfactant can be used in the present invention, mention may be made of sorbitan monostearate (CTFAname: Sorbitan stearate), sold by the company ICI under the name Span 60, sorbitan monopalmitate (CTFA name: Sorbitan palmitate), sold by the company ICI under the name Span 40, and sorbitan tristearate 20 EO (CTFA name: Polysorbate 65), sold by the company ICI under the name Tween 65.

The (4) ethoxylated fatty ethers that are solid at a temperature of less than or equal to 45°C, which may be used as the above nonionic surfactant, are preferably ethers formed from 1 to 100 ethylene oxide units and from at least one fatty alcohol chain containing from 16 to 22 carbon atoms. The fatty chain of the ethers may be chosen in particular from behenyl, arachidyl, stearyl and cetyl units, and mixtures thereof, such as cetearyl. Examples of ethoxylated fatty ethers which may be mentioned are behenyl alcohol ethers comprising 5, 10, 20 and 30 ethylene oxide units (CTFA names: Beheneth-5, Beheneth-10, Beheneth-20, Beheneth-30), such as the products sold under the names Nikkol BB5, BB10, BB20 and BB30 by the company Nikko, and stearyl alcohol ether comprising 2 ethylene oxide units (CTFAname: Steareth-2), such as the product sold under the name Brij 72 by the company ICI. The (4) ethoxylated fatty esters that are solid at a temperature of less than or equal to 45°C, which may be used as the above nonionic surfactant, are esters formed from 1 to 100 ethylene oxide units and from at least one fatty acid chain containing from 16 to 22 carbon atoms. The fatty chain in the esters may be chosen in particular from stearate, behenate, arachidate and palmitate units, and mixtures thereof. Examples of ethoxylated fatty esters which may be mentioned are the ester of stearic acid comprising 40 ethylene oxide units, such as the product sold under the name Myrj 52 (CTFA name: PEG-40 stearate) by the company ICI, as well as the ester of behenic acid comprising 8 ethylene oxide units (CTFA name: PEG-8 behenate), such as the product sold under the name Compritol HD5 ATO by the company Gattefosse. The (5) block copolymers of ethylene oxide (A) and of propylene oxide (B), which may be used as surfactants in the nanoemulsion according to the invention, may be chosen in particular from block copolymers of formula (IV):

HO(C₂¾0)_x(C₃H₆0)_y(C₂¾0)₂H (IV) in which x, y and z are integers such that x+z ranges from 2 to 100 and y ranges from 14 to 60, and mixtures thereof, and more particularly from the block copolymers of formula (IV) having an HLB value ranging from 8.0 to 14. As (6) silicone surfactants which can be used according to the present invention, mention may be made of those disclosed in documents US-A-5364633 and US-A-5411744.

The (6) silicone surfactant as the above nonionic surfactant may preferably be a compound of formula (I):

in which:

Ri, R₂ and R₃, independently of each other, represent a Q-Q alkyl radical or a radical

-(CH₂)_x-(OCH₂CH₂)y-(OCH₂CH₂CH₂)_z-OR₄, at least one radical R R₂ or R₃ not being an alkyl radical; R4 being a hydrogen, an alkyl radical or an acyl radical;

A is an integer ranging from 0 to 200;

B is an integer ranging from 0 to 50; with the proviso that A and B are not simultaneously equal to zero;

x is an integer ranging from 1 to 6;

y is an integer ranging from 1 to 30;

z is an integer ranging from 0 to 5.

According to one preferred embodiment of the invention, in the compound of formula (I), the alkyl radical is a methyl radical, x is an integer ranging from 2 to 6 and y is an integer ranging

As examples of silicone surfactants of formula (I), mention may be made of the compounds of formula (II):

(CH₃)₃SiO - [(CH₃)₂SiO]_A - (CH₃SiO)_E - Si(CH₃)₃

I (ID

(CH₂)₂-(OCH₂CH₂)_y-OH

in which A is an integer ranging from 20 to 105, B is an integer ranging from 2 to 10 and y is an integer ranging from 10 to 20.

As examples of silicone surfactants of formula (I), mention may also be made of the compounds of formula (III):

H-(OCH₂CH2)_y-(CH₂)₃-[(CH₃)₂SiO]A'-(CH₂)3-(OCH₂CH₂)_y-OH (III) in which A' and y are integers ranging from 10 to 20.

Compounds of the invention which may be used are those sold by the company Dow Corning under the names DC 5329, DC 7439-146, DC 2-5695 and Q4-3667. The compounds DC 5329, DC 7439-146 and DC 2-5695 are compounds of formula (II) in which, respectively, A is 22, B is 2 and y is 12; A is 103, B is 10 and y is 12; A is 27, B is 3 and y is 12.

The compound Q4-3667 is a compound of formula (III) in which A is 15 and y is 13. It is preferable that the (b) nonionic surfactant with an HLB value of from 8.0 to 14, preferably from 9.0 to 13.5, and more preferably from 10.0 to 13be chosen from:

polyethylene glycol isostearate or oleate (8 to 10 mol of ethylene oxide),

- polyglyceryl monolaurate or dilaurate comprising 3 to 6 glycerol units,

polyglyceryl mono(iso)stearate comprising 3 to 6 glycerol units,

polyglyceryl monooleate comprising 3 to 6 glycerol units, and

polyglyceryl dioleate comprising 3 to 6 glycerol units. According to a preferable embodiment of the present invention, the nonionic surfactant with an HLB value of from 8.0 to 14, preferably from 9.0 to 13.5, and more preferably from 10.0 to 13, is selected from polyglyceryl fatty acid esters and mono- or poly-oxyalkylenated fatty acid esters.

It is preferable that the polyglyceryl fatty acid ester comprise esters of a fatty acid and

polyglycerine containing 70% or more of polyglycerine whose polymerization degree is 4 or more, preferably esters of a fatty acid and polyglycerine containing equal to or more than 60% of polyglycerine whose polymerization degree is between 4 and 11 , and more preferably esters of a fatty acid and polyglycerine containing equal to or more than 30% of polyglycerine whose polymerization degree is 5.

The polyglyceryl fatty acid ester may be chosen from the mono, di and tri esters of saturated or unsaturated acid, preferably saturated acid, including 2 to 30 carbon atoms, preferably 6 to 30 carbon atoms, and more preferably 8 to 30 carbon atoms, such as lauric acid, oleic acid, stearic acid, isostearic acid, capric acid, caprylic acid, and myristic acid.

It is preferable that the polyglyceryl fatty acid ester be selected from the group consisting of PG-4 laurate, PG-5 laurate, PG5 dilaurate, PG-5 oleate, PG-5 dioleate, PG-6 tricaprylate, PG-5 myristate, PG-5 trimyristate, PG-5 stearate, PG5 isostearate, PG-5 trioleate, PG-6 caprylate, and PG-6 tricaprylate.

It is preferable that the mono- or poly-oxyalkylenated fatty acid ester have a (poly)oxyalkylene moiety derived from 1 to 20 oxyalkylenes, preferably from 3 to 15oxyalkylenes, and more preferably 8 to 10 oxyalkylenes.

The oxyalkylene moiety may be derived from alkylene glycols such as ethyleneglycol, propylene glycol, butyleneglycol, pentyleneglycol, hexyleneglycol, and the like. The oxyalkylene moiety may contain a number of moles of ethylene oxide and/or of propylene oxide of between 1 and 100 and preferably between 2 and 50. Advantageously, the nonionic surfactants do not comprise any oxypropylene units.

The mono- or poly-oxyalkylenated fatty acid ester may be chosen from the mono and di esters of saturated or unsaturated acid, preferably saturated acid, including 2 to 30 carbon atoms, preferably 6 to 30 carbon atoms, and more preferably 8 to 30 carbon atoms, such as lauric acid, oleic acid, stearic acid, isostearic acid, capric acid, caprylic acid, and myristic acid.

Examples of mono- or poly-oxyalkylenated fatty acid esters that may be mentioned include esters of saturated or unsaturated, linear or branched, C₂-C₃₀, preferably C -C₃₀ and more preferably C -C₂₂ acids and of polyethylene glycols. Examples of mono- or poly-oxyalkylenated fatty acid esters that may be mentioned include the adducts of ethylene oxide with esters of lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid or behenic acid, and mixtures thereof, especially those containing from 8 to 20 oxyethylene groups, such as PEG-8 to PEG-20 laurate (as the CTFA names: PEG-8 laurate to PEG-20 laurate); PEG-8 to PEG-20 myristate (as the CTFA names: PEG-8 mysistate to PEG-20 mysistate); PEG-8 to PEG-20 palmitate (as the CTFA names: PEG-8 palmitate to

PEG-20 palmitate); PEG-8 to PEG-20 stearate (as the CTFA names: PEG-8 stearate to PEG-20 stearate); PEG-8 to PEG-20 isostearate (as the CTFA names: PEG-8 isostearate to PEG-20 isostearate); PEG-8 to PEG-20 oleate (as the CTFA names: PEG-8 oleate to PEG-20 oleate); PEG-8 to PEG-20 behenate (as the CTFA names: PEG-8 behenate to PEG-20 behenate); and mixtures thereof.

It is preferable that polyglycol fatty acid ester be selected from the group consisting of PEG-8 isostearate, PEG-8 stearate, PEG10 isostearate, PEG10 oleate, PEG10 isocetyl ether, PEG10 behenyl ether or PEG 10 isostearyl ether and a mixture thereof.

Prefered non ionic surfactants are polyglyceryl fatty acid esters.

The amount in the cosmetic composition according to the present invention of the (b) nonionic surfactant with an HLB value of from 8.0 to 14, preferably from 9.0 to 13.5, and more preferably from 10.0 to 13, is not limited, and may range from 0.1 to 30% by weight, preferably from 1 to 25% by weight, and more preferably from 3 to 20% by weight, relative to the total weight of the composition.

[Vitamin B3 and Derivatives Thereof]

The cosmetic composition according to the present invention comprises at least one compound selected from Vitamin B3 and derivatives thereof. A single type of the compound may be used, but two or more different types of the compound may be used in combination. 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, glycolid acid or palmitic acid.

Mention may also be made of the following derivatives: 2-chloronicotinamide,

6-methylnicotinamide, 6-an inonicotinamide, 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.

It is preferable that the (c) compound selected from Vitamin B3 and derivatives thereof have a log P being from -0.7 to 6, and preferably from -0.5 to 4.

A logP value is a value for the base-ten logarithm of the apparent octan-l-ol/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 -ol and water. The logP may be calculated according to the method described in the article by Meylan and Howard: Atom/Fragment 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 logP 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 amount in the cosmetic composition according to the present invention of the (c) compound selected from Vitamin B3 and derivatives thereof is not limited, and may range from 0.01 to 20% by weight, preferably from 0.1 to 15% by weight, more preferably from 0.5 to 10% by weight, further more preferably 1 to 9% by weight, relative to the total weight of the composition.

[Water]

The cosmetic composition according to the present invention comprises water.

The amount of water is not limited, and may be from 50 to 99% by weight, preferably from 55 to 90% by weight, and more preferably 60 to 85% by weight, relative to the total weight of the composition.

[Additional Surfactant] The cosmetic composition according to the present invention may further comprise at least one nonionic surfactant different from the above (b) and/or at least one additional ionic surfactant. A single type of additional surfactant may be used, but two or more different types of additional surfactant may be used in combination. As the additional surfactant, at least one nonionic surfactant with an HLB value less than 8.0 or more than 14 may be used.

As the additional nonionic surfactant, mention may be made of those listed for the above (b) except that the additional nonionic surfactant has an HLB value less than 8.0, preferably less than 9.0, and more preferably less than 10.0, and more than 14, preferably more than 13.5, and more preferably more than 13.

As the additional surfactant, at least one ionic surfactant may be used. The ionic surfactant can be selected from cationic surfactants, anionic surfactants, and amphoteric surfactants.

(Cationic surfactant)

The cationic surfactant is not limited. The cationic surfactant may be selected from the group consisting of optionally polyoxyalkylenated, primary, secondary or tertiary fatty amine salts, quaternary ammonium salts, and mixtures thereof.

Examples of quaternary ammonium salts that may be mentioned include, but are not limited to: those of general formula (I) below:

aliphatic radicals comprising from 1 to 30 carbon atoms and optionally comprising heteroatoms such as oxygen, nitrogen, sulfur and halogens. The aliphatic radicals may be chosen, for example, from alkyl, alkoxy, C2-C₆ polyoxyalkylene, alkylamide,

(C₁₂-C2₂)alkylamido(C₂-C₆)alkyl, (C₁2-C₂2)alkylacetate and hydroxyalkyl radicals; and aromatic radicals such as aryl and alkylaryl; and X^" is chosen from halides, phosphates, acetates, lactates, (C₂-C₆) alkyl sulfates and alkyl- or alkylaryl-sulfonates;

quaternary ammonium salts of imidazoline;

diquaternary ammonium salts; and

quaternary ammonium salts comprising at least one ester function.

Among the quaternary ammonium salts mentioned above that may be used in compositions according to the invention include, but are not limited to tetraalkylammonium chlorides, for instance dialkyldimemylammonium and alkyltrimemylammonium chlorides in which the alkyl radical comprises from about 12 to 22 carbon atoms, such as behenyltrimethylammonium, distearyldimethylammonium, cetyltrimethylammonium and benzyldimemylstearylammonium chloride; palmitylamidopropyllrimemylammonium chloride; and

stearamidopropyldimethyl(myristyl acetate)ammonium chloride, sold under the name "Ceraphyl® 70" by the company Van Dyk. According to one embodiment, the cationic surfactant that may be used in the compositions of the invention is chosen from quaternary ammonium salts, for example from

behenyltrimemylammonium chloride, cetyltrimethylammonium chloride, Quaternium-83, Quaternium-87, Quaternium-22, behenylamidopropyl-2,3-dmydroxypropyldimemylammonium chloride, palmitylamidopropyltrimemylammonium chloride, and

stearamidopropyldimemylamine.

(Anionic surfactant)

The anionic surfactant is not limited. The anionic surfactants may be chosen in particular from anionic derivatives of proteins of vegetable origin or of silk proteins, phosphates and alkyl phosphates, carboxylates, sulphosuccinates, amino acid derivatives, alkyl sulphates, alkyl ether sulphates, sulphonates, isethionates, taurates, alkyl sulphoacetates, polypeptides, anionic derivatives of alkyl polyglucosides, and their mixtures. 1) Anionic derivatives of proteins of vegetable origin are protein hydrolysates comprising a hydrophobic group, it being possible for the said hydrophobic group to be naturally present in the protein or to be added by reaction of the protein and/or of the protein hydrolysate with a hydrophobic compound. The proteins are of vegetable origin or derived from silk, and the hydrophobic group can in particular be a fatty chain, for example an alkyl chain comprising from 10 to 22 carbon atoms. Mention may more particularly be made, as anionic derivatives of proteins of vegetable origin, of apple, wheat, soybean or oat protein hydrolysates comprising an alkyl chain having from 10 to 22 carbon atoms, and their salts. The alkyl chain can in particular be a lauryl chain and the salt can be a sodium, potassium and/or ammonium salt.

Thus, mention may be made, as protein hydrolysates comprising a hydrophobic group, for example, of salts of protein hydrolysates where the protein is a silk protein modified by lauric acid, such as the product sold under the name Kawa Silk by Kawaken; salts of protein hydrolysates where the protein is a wheat protein modified by lauric acid, such as the potassium salt sold under the name Aminofoam W OR by Croda (CTFA name: potassium lauroyl wheat amino acids) and the sodium salt sold under the name Proteol LW 30 by Seppic (CTFA name: sodium lauroyl wheat amino acids); salts of protein hydrolysates where the protein is an oat protein comprising an alkyl chain having from 10 to 22 carbon atoms and more especially salts of protein hydrolysates where the protein is an oat protein modified by lauric acid, such as the sodium salt sold under the name Proteol OAT (30% aqueous solution) by Seppic (CTFAname: sodium lauroyl oat amino acids); or salts of apple protein hydrolysates comprising an alkyl chain having from 10 to 22 carbon atoms, such as the sodium salt sold under the name Proteol APL (30% aqueous/glycol solution) by Seppic (CTFA name: sodium cocoyl apple amino acids). Mention may also be made of the mixture of lauroyl amino acids (aspartic acid, glutamic acid, glycine, alanine) neutralized with sodium N-methylglycinate sold under the name Proteol SAV 50 S by Seppic (CTFAname:

sodium cocoyl amino acids).

2) Mention may be made, as phosphates and alkyl phosphates, for example, of monoalkyl phosphates and dialkyl phosphates, such as lauryl monophosphate, sold under the name MAP 20® by Kao Chemicals, the potassium salt of dodecyl phosphate, the mixture of mono- and diesters (predominantly diester) sold under the name Crafol AP-31 ® by Cognis, the mixture of octyl phosphate monoester and diester, sold under the name Crafol AP-20® by Cognis, the mixture of ethoxylated (7 mol of EO) 2-butyloctyl phosphate monoester and diester, sold under the name Isofol 12 7 EO-Phosphate Ester® by Condea, the potassium or Iriemanolamine salt of mono(C₁₂-C₁₃)alkyl phosphate, sold under the references Arlatone MAP 230K-40® and Arlatone MAP 230T-60® by Uniqema, potassium lauryl phosphate, sold under the name Dermalcare MAP XC-99/09® by Rhodia Chimie, and potassium cetyl phosphate, sold under the name Arlatone MAP 160K by Uniqema.

3) Mention may be made, as carboxylates, of:

- amido ether carboxylates (AEC), such as sodium lauryl amido ether carboxylate (3 EO), sold under the name Akypo Foam 30® by Kao Chemicals;

polyoxyethylenated carboxylic acid salts, such as oxyethylenated (6 EO) sodium lauryl ether carboxylate (65/25/10 C₁₂-C₁ -C₁₆), sold under the name Akypo Soft 45 NV® by Kao Chemicals, polyoxyethylenated and carboxymethylated fatty acids originating from olive oil, sold under the name Olivem 400® by Biologia E Tecnologia, or oxyethylenated (6 EO) sodium tridecyl ether carboxylate, sold under the name Nikkol ECTD-6NEX® by Nikkol; and

salts of fatty acids (soaps) having a C₆ to C₂₂ alkyl chain which are neutralized with an organic or inorganic base, such as potassium hydroxide, sodium hydroxide, triemanolamine, N-methylglucamine, lysine and arginine.

4) Mention may in particular be made, as amino acid derivatives, of alkali salts of amino acids, such as:

sarcosinates, such as sodium lauroyl sarcosinate, sold under the name Sarkosyl NL 97® by Ciba or sold under the name Oramix L 30® by Seppic, sodium myristoyl sarcosinate, sold under the name Nikkol Sarcosinate MN® by Nikkol, or sodium palmitoyl sarcosinate, sold under the name Nikkol Sarcosinate PN® by Nikkol;

alaninates, such as sodium N-lauroyl-N-methylamidopropionate, sold under the name Sodium Nikkol Alaninate LN 30® by Nikkol or sold under the name Alanone ALE® by Kawaken, or triethanolamine N-lauroyl-N-methylalanine, sold under the name Alanone

ALTA® by Kawaken;

glutamates, such as triemanolamine monococoyl glutamate, sold under the name

Acylglutamate CT-12® by Ajinomoto, triemanolamine lauroyl glutamate, sold under the name Acylglutamate LT-12® by Ajinomoto;

- aspartates, such as the mixture of triethanolamine N-lauroyl aspartate and Iriethanolamine N-myristoyl aspartate, sold under the name Asparack® by Mitsubishi;

glycine derivatives (glycinates), such as sodium N-cocoyl glycinate, sold under the names Amilite GCS-12® and Amilite GCK 12 by Ajinomoto;

citrates, such as the citric monoester of oxyethylenated (9 mol) coco alcohols, sold under the name Witconol EC 1129 by Goldschmidt; and

galacturonates, such as sodium dodecyl D-galactoside uronate, sold by Soliance.

5) Mention may be made, as sulphosuccinates, for example, of oxyethylenated (3 EO) lauryl (70/30 C₁₂/C₁₄) alcohol monosulphosuccinate, sold under the names Setacin 103 Special® and Rewopol SB-FA 30 K 4® by Witco, the disodium salt of a hemisulphosuccinate of C₁₂-C₁₄ alcohols, sold under the name Setacin F Special Paste® by Zschimmer Schwarz, oxyethylenated (2 EO) disodium oleamidosulphosuccinate, sold under the name Standapol SH 135® by Cognis, oxyethylenated (5 EO) lauramide monosulphosuccinate, sold under the name Lebon A-5000® by Sanyo, the disodium salt of oxyethylenated (10 EO) lauryl citrate monosulphosuccinate, sold under the name Rewopol SB CS 50® by Witco, or ricinoleic monoethanolamide

monosulphosuccinate, sold under the name Rewoderm S 1333® by Witco. Use may also be made of polydimethylsiloxane sulphosuccinates, such as disodium PEG- 12 dimethicone sulphosuccinate, sold under the name Mackanate-DC 30 by Maclntyre. 6) Mention may be made, as alkyl sulphates, for example, of triemanolamine lauryl sulphate (CTFA name: TEA lauryl sulphate), such as the product sold by Huntsman under the name Empicol TL40 FL or the product sold by Cognis under the name Texapon T42, which products are at 40% in aqueous solution. Mention may also be made of ammonium lauryl sulphate (CTFA name: ammonium lauryl sulphate), such as the product sold by Huntsman under the name Empicol AL 30FL, which is at 30% in aqueous solution.

7) Mention may be made, as alkyl ether sulphates, for example, of sodium lauryl ether sulphate (CTFA name: sodium laureth sulphate), such as that sold under the names Texapon N40 and Texapon AOS 225 UP by Cognis, or ammonium lauryl ether sulphate (CTFA name: ammonium laureth sulphate), such as that sold under the name Standapol EA-2 by Cognis.

8) Mention may be made, as sulphonates, for example, of a-olefinsulphonates, such as sodium a-olefinsulphonate (Ci₄-C₁₆), sold under the name Bio-Terge AS-40® by Stepan, sold under the names Witconate AOS Protege® and Sulframine AOS PH 12® by Witco or sold under the name Bio-Terge AS-40 CG® by Stepan, secondary sodium olefinsulphonate, sold under the name Hostapur SAS 30® by Clariant; or linear alkylarylsulphonates, such as sodium xylenesulphonate, sold under the names Manrosol SXS30®, Manrosol SXS40® and Manrosol SXS93® by Manro.

9) Mention may be made, as isethionates, of acylisethionates, such as sodium cocoylisethionate, such as the product sold under the name Jordapon CI P® by Jordan.

10) Mention may be made, as taurates, of the sodium salt of palm kernel oil methyltaurate, sold under the name Hostapon CT Pate® by Clariant; N-acyl-N-methyltaurates, such as sodium N-cocoyl-N-methyltaurate, sold under the name Hostapon LT-SF® by Clariant or sold under the name Nikkol CMT-30-T® by Nikkol, Sodium Methyl Stearoyl Taurate sold under the name

Nikkol SMT® or sodium palmitoyl methyltaurate, sold under the name Nikkol PMT® by Nikkol.

11) The anionic derivatives of alkyl polyglucosides can in particular be citrates, tartrates, sulphosuccinates, carbonates and glycerol ethers obtained from alkyl polyglucosides. Mention may be made, for example, of the sodium salt of cocoylpolyglucoside (1 ,4) tartaric ester, sold under the name Eucarol AGE-ET® by Cesalpinia, the disodium salt of cocoylpolyglucoside (1,4) sulphosuccinic ester, sold under the name Essai 512 MP® by Seppic, or the sodium salt of cocoylpolyglucoside (1,4) citric ester, sold under the name Eucarol AGE-EC® by Cesalpinia. It is preferable that the amino acid derivatives be acyl glycine derivatives or glycine derivatives, in particular acyl glycine salt.

The acyl glycine derivatives or glycine derivatives can be chosen from acyl glycine salts (or acyl glycinates) or glycine salts (or glycinates), and in particular from the following. i) Acyl glycinates of formula (I):

R-HNCHiCOOX (I)

in which

R represents an acyl group R'C=0, with R', which represents a saturated or unsaturated, linear or branched, hydrocarbon chain, preferably comprising from 10 to 30 carbon atoms, preferably from 12 to 22 carbon atoms, preferably from 14 to 22 carbon atoms and better still from 16 to 20 carbon atoms, and

X represents a cation chosen, for example, from the ions of alkali metals, such as Na, Li or K, preferably Na or K, the ions of alkaline earth metals, such as Mg, ammonium groups and their mixtures.

The acyl group can in particular be chosen from the lauroyl, myristoyl, behenoyl, palmitoyl, stearoyl, isostearoyl, olivoyl, cocoyl or oleoyl groups and their mixtures. Preferably, R is a cocoyl group. ii) Glycinates of following formula (II): R₂

I

R,— N⁺ CH₂COO -

I

^Rz (ID

in which:

R\ represents a saturated or unsaturated, linear or branched, hydrocarbon chain comprising from 10 to 30 carbon atoms, preferably from 12 to 22 carbon atoms and better still from 16 to 20 carbon atoms; ¾ is advantageously chosen from the lauryl, myristyl, palmityl, stearyl, cetyl, cetearyl or oleyl groups and their mixtures and preferably from the stearyl and oleyl groups,

the R₂ groups, which are identical or different, represent an R"OH group, R" being an alkyl group comprising from 2 to 10 carbon atoms, preferably from 2 to 5 carbon atoms.

Mention may be made, as compound of formula (I), for example, of the compounds carrying the INCI name sodium cocoyl glycinate, such as, for example, Amilite GCS-12, sold by Ajinomoto, or potassium cocoyl glycinate, such as, for example, Amilite GCK-12 from Ajinomoto. Use may be made, as compounds of formula (II), of dihydroxyethyl oleyl glycinate or

dihydroxyethyl stearyl glycinate.

(Amphoteric surfactant) The amphoteric surfactant is not limited. The amphoteric or zwitterionic surfactants can be, for example (nonlimiting list), amine derivatives such as aliphatic secondary or tertiary amine, and optionally quaternized amine derivatives, in which the aliphatic radical is a linear or branched chain comprising 8 to 22 carbon atoms and containing at least one water-solubilizing anionic group (for example, carboxylate, sulphonate, sulphate, phosphate or phosphonate).

Among the amidoaminecarboxylated derivatives, mention may be made of the products sold under the name Miranol, as described in U.S. Pat. Nos. 2,528,378 and 2,781,354 and classified in the CTFA dictionary, 3rd edition, 1982 (the disclosures of which are incorporated herein by reference), under the names Amphocarboxyglycinates and Amphocarboxypropionates, with the respective structures:

R₁-CONHCH₂CH₂-N⁺(R₂)(R₃)(CH₂COO^") in which:

Ri denotes an alkyl radical of an acid Rj-COOH present in hydrolysed coconut oil, a heptyl, nonyl or undecyl radical,

R₂ denotes a beta-hydroxyethyl group, and

R₃ denotes a carboxymethyl group; and R₁'-CONHCH₂CH₂-N(B)(C) in which:

B represents -CH₂CH₂OX',

C represents -(CH2)z-Y', with z=l or 2,

X' denotes a -CH₂CH₂-COOH group, -CH₂-COOZ', -CH₂CH₂-COOH, -CH₂CH₂-COOZ' or a hydrogen atom,

Y' denotes -COOH, -COOZ', -CH₂-CHOH-S0₃Z' or a -CH₂-CHOH-S0₃H radical,

Z' represents an ion of an alkaline or alkaline earth metal such as sodium, an ammonium ion or an ion issued from an organic amine, and

Ri' denotes an alkyl radical of an acid Ri'-COOH present in coconut oil or in hydrolysed linseed oil, an alkyl radical, such as a C , C₉, Cn or C₁₃ alkyl radical, a C₁₇ alkyl radical and its iso form, or an unsaturated C₁₇ radical.

It is preferable that the amphoteric surfactant be selected from (C₈-C2₄)-alkyl amphomonoacetates, (C8-C₂₄)alkyl amphodiacetates, (C8-C2₄)alkyl amphomonopropionates, and (C₈-C₂₄)alkyl amphodipropionates

These compounds are classified in the CTFA dictionary, 5th edition, 1993, under the names Disodium Cocoamphodiacetate, Disodium Lauroamphodiacetate, Disodium

Caprylamphodiacetate, Disodium Capryloamphodiacetate, Disodium Cocoamphodipropionate, Disodium Lauroamphopropionate, Disodium Caprylamphodipropionate, Disodium

Caprylamphodipropionate, Lauroamphodipropionic acid and Cocoamphodipropionic acid.

By way of example, mention may be made of the cocoamphodiacetate sold under the trade name Miranol® C2M concentrate by the company Rhodia Chimie.

Preferably, the amphoteric surfactant may be a betaine.

The betaine-type amphoteric surfactant is preferably selected from the group consisting of alkylbetaines, alkylamidoalkylbetaines, alkylsulfobetaines, alkylphosphobetaines, and

alkylamidoalkylsulfobetaines, in particular, (C₈-C₂₄)alkylbetaines,

(C8-C₂₄)alkylamido(C₁-C8)alkylbetaines, (C₈-C₂₄)alkylsulphobetaines, and

(C8-C₂₄)alkylamido(C_1-C₈)alkylsulphobetaines. In one embodiment, the amphoteric surfactants of betaine type are chosen from (C₈-C₂₄)alkylbetaines,

(C8-C₂₄)all ylamido(C₁-C8)alkylsulphobetaines, (C8-C₂4)alkylsulphobetaines, and

alkyl(C8-C₂₄)phosphobetaines.

Non-limiting examples that may be mentioned include the compounds classified in the CTFA dictionary, 9th edition, 2002, under the names cocobetaine, laurylbetaine, cetylbetaine, coco/oleamidopropylbetaine, cocamido propyl betaine, palmitamido propylbetaine,

stearamidopropylbetaine, cocamidoethylbetaine, cocamidopropylhydroxysultaine,

oleamidopropylhydroxysultaine, cocohydroxysultaine, laurylhydroxysultaine, and cocosultaine, alone or as mixtures.

The betaine-type amphoteric surfactant is preferably an alkylbetaine and an alkylarmdoalkylbetaine, in particular cocobetaine and cocamidopropylbetaine.

The amount of the additional surfactant(s) may be 0.01 wt% to 20wt%, preferably 0.10 wt% to 10 wt%, and more preferably 1 wt% to 5 wt%, relative to the total weight of the composition.

[Polyol]

The cosmetic 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 alk l group, a

hydroxyalkyl group, an alkoxy group, an acylgroup or a carbonyl group.

The polyol may be a C₂-C ₁₂ polyol, preferably a C_2-9 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, propyleneglycol, dipropyleneglycol, butyleneglycol,

pentyleneglycol, hexyleneglycol, 1,3-propanediol, 1,5-pentanediol, polyethyleneglycol (5 to 50 ethyleneoxide groups), and sugars such as sorbitol..

The polyol may be present in an amount ranging from 0.01 % to 30% by weight, and preferably from 0.1% to 20% by weight, such as from 1% to 10% by weight, relative to the total weight of the composition. [Thickening Agent]

The cosmetic composition according to the present invention may further comprise at least one thickening agent. A single type of thickening agent may be used, but two or more different types of thickening agent may be used in combination.

The thickening agent may be selected from organic and inorganic thickeners.

The organic thickeners may be chosen at least one of:

(i) associative thickeners;

(ii) crosslinked acrylic acid homopolymers; (iii) crosslinked copolymers of (meth)acrylic acid and of (C₁-C₆)alkyl acrylate;

(iv) nonionic homopolymers and copolymers comprising at least one of ethylenically unsaturated ester monomers and ethylenically unsaturated amide monomers;

(v) ammonium acrylate homopolymers and copolymers of ammonium acrylate and of acrylamide; (vi) polysaccharides; and

(vii) Q2-C30 fatty alcohols.

The thickening agent is preferably selected from associative thickeners and polysaccharides such as starch and xanthan gum.

As used herein, the expression "associative thickener" means an amphiphilic thickener comprising both hydrophilic units and hydrophobic units, for example, comprising at least one Cg-C₃₀ fatty chain and at least one hydrophilic unit. The viscosity of the cosmetic composition according to the present invention is not particularly limited. The viscosity can be measured at 25 °C with viscosimeters or rheometers preferably with coneplan geometry. Preferably, the viscosity of the cosmetic composition according to the present invention can range, for example, from 1 to 2000 Pa.s, and preferably from 1 to 1000 Pa.s at 25 and ls^"1.

The thickening agent may be present in an amount ranging from 0.001% to 10% by weight, and preferably from 0.01% to 10% by weight, such as from 0.1% to 5% by weight, relative to the total weight of the composition. [Other Ingredients]

The cosmetic composition according to the present invention may also comprise an effective amount of other ingredients, known previously elsewhere compositions, such as various common adjuvants, antiageing agents, whitening agents, anti greasy skin agents, sequestering agents such as EDTA and etidronic acid, UV screening agents, preserving agents, vitamins or

for instance, panthenol, opacifiers, fragrances, plant extracts, cationic polymers and so on.

The cosmetic composition according to the present invention may further comprise at least one organic solvent. So the organic solvent is preferably water miscible. As the organic solvent, there may be mentioned, for example, Q-C₄ alkanols, such as ethanol and isopropanol; aromatic alcohols such as benzyl alcohol and phenoxyethanol; analogous products; and mixtures thereof.

The organic water-soluble solvents may be present in an amount ranging from less than 10% by weight, preferably from 5% by weight or less, and more preferably from 1% by weight or less, relative to the total weight of the composition.

[Preparation and Properties]

The cosmetic composition according to the present invention can be prepared by mixing the above essential and optional ingredients in accordance with a conventional process. The conventional process includes mixing with a high pressure homogenizer (a high energy process). Alternatively, the cosmetic composition can be prepared by a low energy processes such as phase inversion temperature process (PIT), phase inversion concentration (PIC), autoemulsification, and the like. Preferably, the cosmetic composition is prepared by a low energy process.

The ratio of the (b) nonionic surfactant to the (a) oil may be from 0.25 to 6, preferably from 0.3 to 3, and more preferably from 0.4 to 1.5. In particular, the ratio of the (b) nonionic surfactant/the (a) oil is preferably 1 or less, such as from 0.25 to 1, preferably from 0.3 to 1, and more preferably from 0.4 to 1.

The cosmetic 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 broader sense and in a narrower sense. That is to say, there are one case ("microemulsion in the narrow sense") in which the microemulsion 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 the other case ("micro-emulsion in the broad sense") in which among

thermodynamically unstable typical emulsion systems the microemulsion additionally includes those such emulsions presenting transparent or translucent appearances due to their smaller particle sizes (Satoshi Tomomasa, et al., OilChemistry, 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 number average diameter 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) nonionic surfactant 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 and especially a high-pressure homogenizer.

Nanoemulsions can be distinguished from microemulsions by their structure. . Specifically, micro-emulsions are thermodynamically stable dispersions formed from, for example, the (b) nonionic surfactant micells swollen with the (a) oil. Furthermore, microemulsions do not require substantial mechanical energy in order to be prepared. The micro-emulsion may have a dispersed phase with a number average diameter of 300 ran or less, preferably 200 run or less, and more preferably 100 nm or less, measured by laser granulometry. The cosmetic composition according to the present invention may be in the form of an O W nano- or micro-emulsion, a W/O nano- or micro-emulsion or a bicontinuous emulsion. It is preferable that the cosmetic composition according to the present invention be in the form of an O W nano- or micro-emulsion. It is preferable that the cosmetic composition according to the present invention be in the form of an O/W emulsion, and the (a) oil be in the form of a droplet with a number average particle size of 300 nm or less, preferably from 10 nm to 150 nm, and more preferably 20 nm to 140 nm.

The cosmetic composition according to the present invention can have a transparent or slightly translucent appearance, preferably a transparent appearacnce.

The transparency may be measured by measuring the transmittance with absorption spectrometer in the visible region (for example, Transparency was measured with a V-550 (JASCO) with a 2 mm width cell as an average of visible light transmittance (between 400 and 800 nm).). The measurement is taken on the undiluted composition. The blank is determined with distilled water.

The cosmetic composition according to the present invention may preferably have a transparency greater than 50%, preferably greater than 60%, more preferably greater than 70%, and even more preferably greater than 80%.

[Process and Use]

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

The present invention also relates to a use of the cosmetic composition according to the present invention, as it is or in care products and/or washing products and/or make-up products and/or make-up-removing 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 cosmetic composition according to the present invention can be used, as it is, as the above product. Alternatively, the cosmetic composition according to the present invention can be used as an element of the above product. For example the cosmetic composition according to the present invention can be added to or combined with any other elements to form the above product. The care product may be a lotion, a cream, a serum, a hair tonic, a hair conditioner, a sun screening agent, and the like. The washing product may be a shampoo, a face wash, a hand wash and the like. The make-up product may be a foundation, a mascara, a lipstick, a lip gloss, a blusher, an eye shadow, a nail varnish, and the like. The make-up-removing product may be a make-up cleansing agent 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.

(Particle Size) Particle size was measured with a VASCO-2 (CORDOUAN TECHNOLOGIES) with non diluted condition.

(Transparency) Transparency was measured with a V-550 (JASCO) with a 2 mm width cell as an average of visible light transmittance (between 400 and 800 nm).

[Example 1 and Comparative Example 1]

The following compositions according to Example 1 and Comparative Example 1, shown in Table 1, were prepared by mixing the components shown in Table 1 as follows: (1) mixing isopropyl palmitate and polyglyceryl-5 laurate to form an oil phase; (2) heating the oil phase up to around 75 °C; (3) mixing water and Vitamin B3, if used, to form an aqueous phase; and (4) adding the water phase into the oil phase followed by mixing them to obtain an O/W emulsion. The numerical values for the amounts of the components shown in Table 1 are all based on "% by weight" as active raw materials.

Table 1

(*) SUNSOFT A-121E (Taiyo Kagaku) The aspect, particle size of oil droplet and transparency of the obtained O/W emulsions according to Example 1 and Comparative Example 1 are shown in Table 2.

Table 2

[Example 2 and Comparative Example 2]

The following compositions according to Example 2 and Comparative Example 2, shown in Table 3, were prepared by mixing the components shown in Table 3 as follows: (1) mixing isopropyl palmitate and polyglyceryl-5 laurate to form an oil phase; (2) heating the oil phase up to around 75 °C; (3) mixing water and Vitamin B3, if used, to form an aqueous phase; and (4) adding the water phase into the oil phase followed by mixing them to obtain an O/W emulsion. The numerical values for the amounts of the components shown in Table 3 are all based on "% by weight" as active raw materials.

Table 3

(*) SUNSOFT A-121E (Taiyo Kagaku)

The aspect, particle size of oil droplet and transparency of the obtained O/W emulsions according to Example 2 and Comparative Example 2 are shown in Table 4.

Table 4

[Example 3 and Comparative Example 3]

The following compositions according to Example 3 and Comparative Example 3, shown in Table 5, were prepared by mixing the components shown in Table 5 as follows: (1) mixing ethylhexyl palmitate and polyglyceryl-5 laurate to form an oil phase; (2) heating the oil phase up to around 75 °C; (3) mixing water and Vitamin B3, if used, to form an aqueous phase; and (4) adding the water phase into the oil phase followed by mixing them to obtain an O W emulsion. The numerical values for the amounts of the components shown in Table 5 are all based on "% by weight" as active raw materials.

Table 5

(*) SUNSOFT A-121E (Taiyo Kagaku)

The aspect, particle size of oil droplet and transparency of the obtained O/W emulsions according to Example 3 and Comparative Example 3 are shown in Table 6.

Table 6

[Example 4 and Comparative Example 4]

The following compositions according to Example 4 and Comparative Example 4, shown in Table 7, were prepared by mixing the components shown in Table 7 as follows: (1) mixing ethylhexyl palmitate and polyglyceryl-5 laurate to form an oil phase; (2) heating the oil phase up to around 75 °C; (3) mixing water and Vitamin B3, if used, to form an aqueous phase; and (4) adding the water phase into the oil phase followed by mixing them to obtain an O/W emulsion. The numerical values for the amounts of the components shown in Table 7 are all based on "% by weight" as active raw materials.

Table 7

(*) SUNSOFT A-12 IE (Taiyo Kagaku)

The aspect, the particle size of the oil droplet and the transparency of the obtained OAV emulsions according to Example 4 and Comparative Example 4 are shown in Table 8.

Table 8

[Example 5, Example 6 and Comparative Example 5]

The following compositions according to Example 5, Example 6 and Comparative Example 5, shown in Table 9, were prepared by mixing the components shown in Table 9 as follows: (1) mixing hydrogenated polyisobutene and polyglyceryl-8 isostearate to form an oil phase; (2) heating the oil phase up to around 75 °C; (3) mixing water and Vitamin B3, if used, to form an aqueous phase; and (4) adding the water phase into the oil phase followed by mixing them to obtain an OAV emulsion. The numerical values for the amounts of the components shown in Table 9 are all based on "% by weight" as active raw materials.

Table 9

(*) SUNSOFT A-12 IE (Taiyo Kagaku)

The aspect, the particle size of the oil droplet and the transparency of the obtained OAV emulsions according to Example 5, Example 6 and Comparative Example 5 are shown in Table 10.

Table 10

[Example 7 and Comparative Example 6]

The following compositions according to Example 7 and Comparative Example 6, shown in Table 11, were prepared by mixing the components shown in Table 11 as follows: (1) mixing isopropyl myristate and polyglyceryl-5 oleate to form an oil phase; (2) heating the oil phase up to around 75 °C; (3) mixing water and Vitamin B3, if used, to form an aqueous phase; and (4) adding the water phase into the oil phase followed by mixing them to obtain an O W emulsion. The numerical values for the amounts of the components shown in Table 11 are all based on "% by weight" as active raw materials.

Table 11

(*) SUNSOFT A-171E (Taiyo Kagaku) The aspect, the particle size of the oil droplet and the transparency of the obtained O/W emulsions according to Example 7 and Comparative Example 6 are shown in Table 12.

Table 12

As is clear from the above results, it was found that the cosmetic compositions in the form of an O/W emulsion according to the present invention had smaller oil droplets, and therefore, transparent or slightly translucent aspect with better transparency was provided, due to the presence of Vitamin B3.

Claims

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

(a) at least one oil;

(c) at least one compound selected from Vitamin B3 and derivatives thereof; and

(d) water.

The cosmetic composition according to Claim 1, wherein the (a) oil is selected from the group consisting of oils of plant or animal origin, synthetic oils, silicone oils and hydrocarbon oils.

The cosmetic composition according to Claim 1 or 2, wherein the (a) oil is chosen from hydrocarbon oils which are in the form of a liquid at a room temperature.

The cosmetic composition according to any one of Claims 1 to 3, where the (a) oil is chosen from oils with molecular weight below 600 g/mol.

The cosmetic composition according to any one of Claims 1 to 4, wherein the amount of the (a) oil ranges from 0.1 to 50% by weight, preferably from 0.5 to 40% by weight, and more preferably from 3 to 30% by weight, relative to the total weight of the composition.

The cosmetic composition according to any one of Claims 1 to 5, wherein the (b) nonionic surfactant is chosen from:

surfactants that are fluid at a temperature of less than or equal to 45 °C, chosen from the esters of at least one polyol chosen from the group formed by polyethylene glycol comprising from 1 to 60 ethylene oxide units, sorbitan, glycerol comprising from 2 to 30 ethylene oxide units, polyglycerols comprising from 2 to 12 glycerol units, and of at least one fatty acid comprising at least one saturated or unsaturated, linear or branched C₈-C₂₂ alkyl chain,

surfactants that are solid at a temperature of less than or equal to 45°C, chosen from fatty esters of glycerol, fatty esters of sorbitan and oxyethylenated fatty esters of sorbitan, ethoxylated fatty ethers and ethoxylated fatty esters,

block copolymers of ethylene oxide (A) and of propylene oxide (B), and

silicone surfactants.

The cosmetic composition according to any one of Claims 1 to 6, characterized in that the

(b) nonionic surfactant is chosen from:

polyethylene glycol isostearate or oleate (8 to 10 mol of ethylene oxide),

polyglyceryl monolaurate or dilaurate comprising 3 to 6 glycerol units, polyglyceryl mono(iso)stearate comprising 3 to 6 glycerol units,

polyglyceryl monooleate comprising 3 to 6 glycerol units, and

polyglyceryl dioleate comprising 3 to 6 glycerol units.

8. The cosmetic composition according to any one of Claims 1 to 7, wherein the (b) nonionic surfactant is chosen from polyglyceryl fatty acid esters, preferably esters of a fatty acid and polyglycerine comprising 70% or more of polyglycerine whose polymerization degree is 4 or more, preferably esters of a fatty acid and polyglycerine containing equal to or more than 60% of polyglycerine whose polymerization degree is between 4 and 11, and more preferably esters of a fatty acid and polyglycerine containing equal to or more than 30% of polyglycerine whose polymerization degree is 5.

9. The cosmetic composition according to any one of Claims 1 to 8, wherein the amount of the (b) nonionic surfactant ranges from 0.1 to 30% by weight, preferably from 1 to 25% by weight, and more preferably from 3 to 20% by weight, relative to the total weight of the composition.

10. The cosmetic composition according to any one of Claims 1 to 9, wherein the ratio of the (b) nonionic surfactant to the (a) oil is from 0.25 to 6, preferably from 0.3 to 3, and more preferably from 0.4 to 1.5.

11. The cosmetic composition according to any one of Claims 1 to 10, wherein the (c)

compound has a log P being from -0.7 to 6, preferably from -0.5 to 4.

12. The cosmetic composition according to any one of Claims 1 to 11 , wherein the (c)

compound is niacinnamide.

13. The cosmetic composition according to any one of Claims 1 to 12, wherein the amount of the (c) compound ranges from 0.01 to 20% by weight, preferably from 0.1 to 15% by weight, and more preferably from 1 to 10% by weight, relative to the total weight of the composition.

14. The cosmetic composition according to any one of Claims 1 to 13, further comprising at least one nonionic surfactant different from the above (b) and/or at least one ionic surfactant.

15. The cosmetic composition according to any one of Claims 1 to 14, further comprising at least one polyol.

16. The cosmetic composition according to any one of Claims 1 to 15, further comprising at least one thickening agent, preferably selected from associative thickeners.

17. The cosmetic composition according to any one of Claims 1 to 16, wherein the cosmetic composition is in the form of an O/W emulsion, and the (a) oil is in the form of a droplet with a number average particle size of 300 nm or less, preferably from 10 nm to 150 nm.

18. The cosmetic composition according to any one of Claims 1 to 17, wherein the cosmetic composition has a transparency greater than 50%, preferably greater than 60%, and more preferably greater than 70%.

19. A non-therapeutic process for treating the skin, the hair, mucous membranes, the nails, the eyelashes, the eyebrows and/or the scalp, characterized in that the cosmetic composition according to any one of Claims 1 to 18 is applied to the skin, the hair, mucous membranes, the nails, the eyelashes, the eyebrows or the scalp.

20. Use of the cosmetic composition according to any one of Claims 1 to 18, as or in care products and/or washing products and/or make-up products and/or make-up-removing 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.