WO2023120259A1

WO2023120259A1 - Stable composition comprising retinoid

Info

Publication number: WO2023120259A1
Application number: PCT/JP2022/045580
Authority: WO
Inventors: L'oreal; Kazuhiko Maruyama; Makoto Saito; Yukinori Yamada; Tomoyoshi MITERA
Original assignee: LOreal SA
Current assignee: LOreal SA
Priority date: 2021-12-20
Filing date: 2022-12-06
Publication date: 2023-06-29
Anticipated expiration: 2024-06-20
Also published as: KR20240099313A; WO2023120259A8

Abstract

The present invention relates to a composition comprising: (a) at least one retinoid; (b) at least one lipophilic antioxidant agent; (c) at least one light shielding compound; (d) at least one oil selected form triglycerides, preferably triglycerides having at least one unsaturated fatty acid residue, and more preferably triglycerides having at least one polyunsaturated fatty acid residue; and (e) at least one optional polysaccharide. The composition according to the present invention is stable under light exposure and different temperature conditions, and can maintain the retinoid therein at a sufficient residual rate even under light exposure and at high temperature.

Description

DESCRIPTION

TITLE OF INVENTION

STABLE COMPOSITION COMPRISING RETINOID

TECHNICAL FIELD

The present invention relates to a composition, preferably a cosmetic composition, which is stable and comprises at least one retinoid.

BACKGROUND ART

Retinoids have been known to be useful in the field of, for example, cosmetics because they can function as anti-aging active ingredients which may be used for wrinkle treatments and the like. However, they tend to be unstable under some conditions. For example, retinol is soluble in lipophilic solvents, but the solution of retinol may rapidly discolor (yellowing /browning) and the retinol therein may degrade over time.

Compositions including retinoid(s) also have problems in stability such that they tend to become discolored and give off a bad smell, depending on conditions regarding light or temperature, and the retinoid(s) in the compositions degrade(s) over time under light exposure or at high temperature. However, sufficient investigations have not yet been made for the technique of effectively preventing the discoloration and the bad smell of the compositions including retinoid(s), and the degradation due to light or high temperature of the retinoid(s) over time in the compositions.

DISCLOSURE OF INVENTION

An objective of the present invention is to provide a composition including at least one retinoid wherein the composition is stable under light exposure and different temperature conditions, and can maintain the retinoid therein at a sufficient residual rate even under light exposure and at high temperature.

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

(a) at least one retinoid;

(b) at least one lipophilic antioxidant agent;

(c) at least one compound which is capable of providing a solution thereof with a transmittance of 10% or less, preferably 5% or less, and more preferably 2% or less, for light with a wavelength of from 290 to 420 run, along a light path length of 10 mm, the concentration of the compound in the solution being 0.9% by weight relative to the total weight of the solution;

(d) at least one oil selected form triglycerides, preferably triglycerides having at least one unsaturated fatty acid residue, and more preferably triglycerides having at least one polyunsaturated fatty acid residue; and

(e) at least one optional polysaccharide, preferably selected from polysaccharides derived from plants, and more preferably selected from algal extracts.

The (a) retinoid may be retinol. The amount of the (a) retinoid(s) in the composition according to the present invention may range from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, and more preferably from 0.1% to 1% by weight, relative to the total weight of the composition.

The (b) lipophilic antioxidant agent may be selected from biodegradable lipophilic antioxidant agents, and preferably tocopherol, pentaerythrityl tetra-di-t-butyl hydroxyhydrocinnamate, and a mixture thereof.

The amount of the (b) lipophilic antioxidant agent(s) in the composition according to the present invention may range from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, and more preferably from 0.1% to 1% by weight, relative to the total weight of the composition.

The (c) compound may be selected from polyphenols, preferably quercetin, isoquercetin, rutin, gluco sylrutin, and a mixture thereof.

The amount of the (c) compound in the composition according to the present invention may range from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, and more preferably from 0.1% to 2% by weight, relative to the total weight of the composition.

The (d) oil may be selected from plant oils, preferably from the group consisting of soybean oil, com oil, cotton seed oil, grape seed oil, and a mixture thereof.

The amount of the (d) oil in the composition according to the present invention may range from 0.1% to 20% by weight, preferably from 0.5% to 15% by weight, and more preferably from 1% to 10% by weight, relative to the total weight of the composition.

The (e) polysaccharide may be selected from agar, alginate, carrageenan and a mixture thereof.

The amount of the (e) polysaccharide(s) in the composition according to the present invention may range from 0.001% to 5% by weight, preferably from 0.005% to 2% by weight, and more preferably from 0.01% to 1% by weight, relative to the total weight of the composition.

If the composition according to the present invention comprises no (e) polysaccharide, it comprises (f) at least one chelating agent, preferably a biodegradable chelating agent, and more preferably trisodium ethylenediamine disuccinate.

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

The composition according to the present invention may be in the O/W form, preferably an O/W emulsion or an O/W dispersion, and more preferably an O/W gel emulsion or an O/W gel dispersion.

The present invention also relates to a cosmetic process for treating a keratin substance such as skin, comprising the step of applying the composition according to the present invention to the keratin substance. BEST MODE FOR CARRYING OUT THE INVENTION

After diligent research, the inventors have discovered that it is possible to provide a composition including at least one retinoid wherein the composition is stable under light exposure and different temperature conditions, and can maintain the retinoid therein at a sufficient residual rate even under light exposure and at high temperature.

The composition according to the present invention may be characterized by a combination of:

(a) at least one retinoid;

(b) at least one lipophilic antioxidant agent;

(c) at least one compound which is capable of providing a solution thereof with a transmittance of 10% or less, preferably 5% or less, and more preferably 2% or less, for light with a wavelength of from 290 to 420 nm, along a light path length of 10 mm, the concentration of the compound in the solution being 0.9% by weight relative to the total weight of the solution;

The composition according to the present invention is stable under light exposure and different temperature conditions, and can maintain the retinoid therein at a sufficient residual rate even under light exposure and at high temperature.

The ingredient (e) in the composition according to the present invention is optional. Therefore, the composition according to the present invention may or may not comprise the ingredient (e).

If the composition according to the present invention comprises the ingredient (e), the composition according to the present invention may not comprise the ingredient (f). The composition according to the present invention which comprises the ingredient (e) may be in the form of an O/W gel emulsion or an O/W gel dispersion.

If the composition according to the present invention does not comprise the ingredient (e), the composition according to the present invention comprises the ingredient (f). The composition according to the present invention which does not comprise the ingredient (e) may be in the form of an O/W emulsion or an O/W dispersion.

The composition according to the present invention is stable under light exposure and a variety of temperature conditions. Thus, the term “stable” here reflects both photo-stability and thermo-stability, and means that the conditions, such as aspect, color and smell, of a composition does not change over time under exposure of light (e.g., UV rays) and at a variety of constant temperatures such as 4 °C, 25 °C, 37 °C and 45 °C.

Since the composition according to the present invention is stable, it can cause, for example, no or little separation or creaming, no or little discoloration, such as yellowing, and no or little bad odor, for a long period of time. The composition according to the present invention can be stored for a long period of time, because it can cause no or little changes such as creaming, yellowing, and causing bad odor.

The composition according to the present invention can maintain the (a) retinoid therein at a sufficient residual rate (such as 80% or more) even under light (e.g., UV rays) exposure and at high temperature (e.g., 45°C). In other words, the degradation of the (a) retinoid in the composition according to the present invention due to light and high temperature can be reduced. Accordingly, the composition according to the present invention can provide stable cosmetic effects over time based on the (a) retinoid in the composition.

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

[Retinoid]

The composition according to the present invention comprises (a) at least one retinoid. Two or more (a) retinoids may be used in combination. Thus, a single type of retinoid or a combination of different types of retinoid may be used.

The (a) retinoid may be retinol (vitamin A), retinal (vitamin A aldehyde), retinoic acid (vitamin A acid), or an ester of retinol and of a C_2-20 acid, such as the propionate, the acetate, the linoleate or the palmitate of retinol (retinyl palmitate).

Among the (a) retinoid, mention may be made of retinol, retinal, retinoic acid, in particular all-trans retinoic acid and 13 -cis retinoic acid, retinol derivatives, such as retinyl acetate, propionate or palmitate, and the retinoids described in the following patent applications: FR 2 370 377, EP 0 199 636. EP 0 325 540 and EP 0 402 072:

According to one preferred embodiment of the present invention, the (a) retinoid is retinol or proretinol.

The term "retinol" is intended to mean all the isomers of retinol, i.e., all-trans retinol, 13-cis retinol, 11-cis retinol, 9-cis retinol and 3,4-didehydro retinol.

As a representative of proretinol, mention may be made of retinyl palmitate.

It is preferable that the (a) retinoid be retinol.

The amount of the (a) retinoid(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 (a) retinoid(s) in the composition according to the present invention may be 5% by weight or less, preferably 3% 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) retinoid(s) in the composition according to the present invention may range from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, more preferably from 0.1% to 1% by weight, relative to the total weight of the composition. [Lipophilic Antioxidant Agent]

The composition according to the present invention comprises (b) at least one lipophilic antioxidant agent. A single type of lipophilic antioxidant agent may be used, but two or more different types of lipophilic antioxidant agent may be used in combination.

According to the present invention, antioxidant agents are compounds or substances that can scavenge the various radical forms which may be present in the skin; preferably, they simultaneously scavenge all the various radical forms present.

The (b) lipophilic antioxidant agent is different from the (a) retinoid.

The (b) lipophilic antioxidant agent means that the partition coefficient of the antioxidant agent between n-butanol and water is >1, more preferably >10 and even more preferably >100.

As the (b) lipophilic antioxidant agents, mention may be made of, phenolic antioxidants which have a hindered phenol structure or a semi-hindered phenol structure within the molecule. As specific examples of such compounds, mention may be made of 3,5-bis(l,l-dimethylethyl)-4-hydroxybenzenepropanoic acid) which has the INCI name of pentaerythrityl tetra-di-t-butyl hydroxyhydrocinnamate, 2,6-di-tert-butyl-4-methylphenol, 2,6- di-tert-butyl-4-ethylphenol, mono- or di- or tri-(a-methylbenzyl)phenol, 2,2’-methylenebis(4- ethyl-6-tert-butylphenol), 2,2’-methylenebis(4-methyl-6-tert-butylphenol), 4,4’- butylidenebis(3-methyl-6-tert-butylphenol), 4,4’-thiobis(3-methyl-6-tert-butylphenol), 2,5-di- tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone, tris[N-(3,5-di-tert-butyl-4- hydroxybenzyl)]isocyanurate, l,l,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, butylidene- 1 , 1 bis [3 -(3 -tert-butyl-4-hydroxy-5 -methylphenyl)propionate] , octadecyl 3 -(3 ,5 -di- tert-butyl-4-hydroxyphenyl)propionate, tetrakis[methylene-3-(3,5-di-tert-butyl-4- hydroxyphenyl)propionato]methane, triethylene glycol bis[3-(3-tert-butyl-4-hydroxy-5- methylphenyl)propionate] , 3 ,9-bis {2- [3 -(3 -tert-butyl -4-hy droxy-5 - methylphenyl)propionyloxy]-l , 1 -dimethylethyl} -2,4,8, 10-tetraoxaspiro [5.5] undecane, 1,3,5- trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 2,2-thiodiethylenebis[3-(3,5- di-tert-butyl-4-hydroxyphenyl)propionate], N,N’-hexamethylenebis(3,5-di-tert-butyl-4- hydroxyhydrocinnamide), 1 ,6-hexanediol bis[3-(3,5-di-tert-butyl-4- hydroxyphenyl)propionate], 1 ,3,5-tris[(4-tert-butyl-3-hydroxy-2,6-xylyl)methyl]-l ,3,5- triazine-2, 4, 6-trione, 2,4-bis(n-octylthio)-6-(4-hydroxy-3,5-di-tert-butylanilino)-l,3,5-triazine, 2-tert-butyl-6-(3 ’ -tert-butyl-5 ’ -methyl-2 ’ -hydroxybenzyl)-4-methylphenyl acrylate, 2- [ 1 -(2- hydroxy-3,5-di-tert-pentylphenyl)ethyl]-4,6-di-tert-pentylphenyl acrylate, 4,6- bis[(octylthio)methyl]-o-cresol, 2, 4-di-tert-butylphenyl-3, 5 -di -tert-butyl -4-hydroxybenzoate and 1 ,6-hexanediolbis[3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate].

As the (b) lipophilic antioxidant agents, mention may also be made of: BHA (butylated hydroxyl anisole) and BHT (butylated hydroxyl toluene), vitamin E (or tocopherols and tocotrienol) and derivatives thereof, such as the phosphate derivative, for instance TPNA® sold by the company Showa Denko, coenzyme Q10 (or ubiquinone), idebenone, certain carotenoids such as lutein, astaxanthin, beta-carotene, and phenolic acids and derivatives (e. g., chlorogenic acid).

The (b) lipophilic antioxidant agents that may also be mentioned include dithiolanes, for instance asparagusic acid, or derivatives thereof, for instance siliceous dithiolane derivatives, especially such as those described in patent application FR 2 908 769.

The (b) lipophilic antioxidant agents that may also be mentioned include: glutathione and derivatives thereof (GSH and/or GSHOEt), such as glutathione alkyl esters (such as those described in patent applications FR 2 704 754 and FR 2 908 769); cysteine and derivatives thereof, such as N-acetylcysteine or L-2-oxothiazolidine-4-carboxylic acid. Reference may also be made to the cysteine derivatives described in patent applications FR 2 877 004 and FR 2 854 160; certain enzymes for defending against oxidative stress, such as catalase, superoxide dismutase (SOD), lactoperoxidase, glutathione peroxidase and quinone reductases; benzylcyclanones; substituted naphthalenones; pidolates (as described especially in patent application EP 0 511 118); caffeic acid and derivatives thereof, gamma-oryzanol; melatonin, sulforaphane and extracts containing it (excluding cress); the diisopropyl ester of N,N'-bis(benzyl)ethylenediamine-N,N'-diacetic acid, as described especially in patent applications WO 94/11338, FR 2 698 095, FR 2 737 205 or EP 0 755 925; deferoxamine (or desferal) as described in patent application FR 2 825 920.

The (b) lipophilic antioxidant agents that may also be used are chaicones, more particularly phloretin or neohesperidin, the diisopropyl ester of N,N'-bis(benzyl)ethylenediamine-N,N'- diacetic acid or an extract of pinaster bark such as PYCNOGENOL®.

As examples of the (b) lipophilic antioxidant agents, mention may also be made of pentaerythrityl tetra-di-t-butyl hydroxyhydrocinnamate, nordihydroguaiaretic acid, tocopherol, resveratrol, propyl gallate, butylated hydroxyl toluene, butylated hydroxyl anisole, ascorbyl palmitate, tocopherol, and mixtures thereof.

It is preferable that the (b) lipophilic antioxidant agent be biodegradable. In this sense, BHT which is not biodegradable, is not preferable as the (b) lipophilic antioxidant agent. Thus, it is preferable not to use BHT as the (b) lipophilic antioxidant agent. Furthermore, it is preferable that the composition according to the present invention is free from BHT.

The term “free from” here means that the composition according to the present invention may contain a limited amount of BHT. However, it is preferable that the amount of BHT be limited such that it is less than 1% by weight, more preferably less than 0.1% by weight, and even more preferably less than 0.01% by weight, relative to the total weight of the composition. It is most preferable that the composition according to the present invention comprise no BHT.

It is more preferable that the (b) lipophilic antioxidant agent be selected from tocopherol, pentaerythrityl tetra-di-t-butyl hydroxyhydrocinnamate, and a mixture thereof.

The amount of the (b) lipophilic antioxidant agent(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) lipophilic antioxidant agent(s) in the composition according to the present invention may be 5% by weight or less, preferably 3% by weight or less, and more preferably 1% by weight or less, relative to the total weight of the composition.

[Light Shielding Compound]

The composition according to the present invention comprises (c) at least one compound which is capable of providing a solution thereof with a transmittance of 10% or less, preferably 5% or less, and more preferably 2% or less, for light with a wavelength of from 290 to 420 nm, along a light path length of 10 mm, wherein the concentration of the (c) compound in the solution is 0.9% by weight relative to the total weight of the solution. Thus, a single type of such (c) compound or a combination of different types of such (c) compounds may be used.

The (c) compound can provide a low light transmittance. Therefore, the (c) compound may be referred to as a light shielding compound.

It is more preferable that the (c) compound be capable of providing a solution with a zero (0) transmittance for light with a wavelength of from 290 to 420 nm along a light path length of 10 mm, wherein the concentration of the (c) compound in the solution is 0.9% by weight relative to the total weight of the solution.

It is even more preferable that the (c) compound be capable of providing a solution with a zero (0) transmittance for light with a wavelength of from 290 to 420 nm along a light path length of 10 mm, wherein the concentration of the (c) compound in the solution is more than 0.1% by weight relative to the total weight of the solution.

The solvent for the solution is not limited as long as the (c) compound is solubilized in the solvent, and the solvent does not have any absorbance for light with a wavelength of from 290 to 420 nm. For example, as the solvent, water and hydrophilic solvents such as ethanol may be used.

The transmittance may be measured by a spectrophotometer, e.g., a UV-Visible/NIR spectrophotometer V-750 by JASCO Corp.

The (c) compound can provide a solution with a transmittance of 10% or less, preferably 5% or less, more preferably 2% or less, and even more preferably zero (0)% for any light with a wavelength of from 290 to 420 nm along a light path length of 10 mm. In other words, the solution of the (c) compound can reduce or shield any light whose wavelength is from 290 nm to 420 nm.

The (c) compound can reduce or shield the light with the above specific wavelength which could reach the (a) retinoid in the composition according to the present invention to cause the decomposition of the (a) retinoid. Therefore, the (c) compound can contribute to enhance the photo-stability of the (a) retinoid, and can reduce the decomposition of the (a) retinoid in the composition according to the present invention.

The (c) compound may be selected from polyphenols.

(Polyphenol) The expression "polyphenol" is understood to mean a compound containing a plurality of phenolic hydroxyl groups. The phenolic hydroxyl group means a hydroxyl group bonded to an aromatic ring such as a benzene ring and a naphthalene ring. The phenolic hydroxyl group may be optionally etherified or esterified.

The polyphenol may be chosen from those which have an antioxidizing activity.

The polyphenol may be chosen, for example, from flavonoids.

Preferred flavonoids may correspond to general formula (I):

in which

A", B", C" and D", independently of one another, represent H, OH, -R' or -OR', where R' represents the residue of a sugar of formula R'OH;

E" represents H, -OH or -OX', where X' represents:

F", G" and J" represent, independently of one another, H, -OH or -OCH3; and Xi represents -CH2-, -CO- or -CHOH-,or general formula (II):

in which

A', C and D', independently of one another, represent H, -OH, -OCH3, -R' or -OR', where R' represents the residue of a sugar of formula R'OH; E' represents H, -OH or -OR', where R' represents the residue of a sugar of formula R'OH; and B', F', G' and J', independently of one another, represent H, -OH, -OCH₃, -OCH₂-CH₂-OH, or -OR', where R' represents the residue of a sugar of formula R'OH.

Rutinose, glucose, apiose, rhamnose, robinose, neohesperidose, or a combination thereof, may be mentioned among the sugars R'OH.

The compounds of formulae (I) and (II) are known. They can be obtained especially according to the processes described in "The Flavonoids", Harbome J. B., Mabry T. J., Helga Mabry, 1975, pages 1 to 45.

The flavonoids may be selected from flavones, flavonols, isoflavones, flavanols, flavanones, anthocyanidins, and mixtures thereof.

Among the flavonoids which can be used for the present invention, mention may be made of apigenin, apiin, apigetrin, vitexin, chrysin, toringin, luteolin, orientin, galangin, quercetin, isoquercetin, rutin, glucosylrutin, quercitrin, isoquercitrin, kaempferol, astragalin, kaempferitrin, robinin, myricetin, daidzein, daidzin, genistein, genistein, glycitein, glycitin, catechin, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, theaflavin, naringenin, narirutin, naringin, hesperetin, hesperidin, glucosylhesperidin, anthocyanidin, anthocyanin, cyanidin, cyanin, delphinidin, delphinin, pelargonidin, and pelargonin.

Certain polyphenols which can be used are present in plants from which they can be extracted in a known way. It is possible to use extracts from tea leaves (Camellia sinensis or Camellia japonica). Mention will in particular be made of the green tea extracts sold under the name SUNPHENON® by the Company Taiyo, which especially contain flavonoids.

As the polyphenol, it is possible to use a mixture of glucosylrutin and rutin sold under the name ALPHA GLUCOSYL RUTIN by the company QINGDAO TAITONG PHARMACEUTICAL.

Among the polyphenols which can be used, mention will also be made of the polyphenols such as camosic acid and camosol which can be extracted, for example, from rosemary, either by extraction followed by distillation (Chang et al., JOSC, Vol. 61, No. 6, June 1984) or by extraction with a polar solvent such as ethanol preceded by extraction using a nonpolar solvent such as hexane to remove the odorant substances, as described in EP-A-307,626.

Polyphenol may also be chosen from (2,5-dihydroxyphenyl)alkylenecarboxylic acids of formula (III) and their derivatives (especially esters and amides):

in which

R₁" represents -O-Alk, OH or -N(r')(r"), wherein Aik denotes a linear or branched C₁-C₂₀ alkyl, optionally substituted by one or more hydroxyl or alkoxy groups, or a C₂-C₂₀ alkenyl, r' and r" independently represent H, C₁-C₂₀ alkyl, C₂-C₆ hydroxyalkyl or C₃-C₆ polyhydroxyalkyl, or alternatively r' and r" form, together with a nitrogen atom to which they are attached, a heterocycle, r is a number, including zero, such that the -(CH₂)_r-COR₁ chain contains at most 21 carbon atoms, and

R₂" and R₃" independently represent H or a C₁-C₄ alkyl, it additionally being possible for R₂" to represent a C₁-C₄ alkoxy.

The compounds of formula (III) are known or can be prepared according to known methods, for example analogous to those described in patents FR-2,400,358 and FR-2,400,359.

Polyphenol may also be chosen from esters or amides of caffeic acid.

Among the esters of caffeic acid, mention may especially be made of the compounds of formula (IV):

in which

Z represents a C₁-C₈ alkyl, for example methyl, or the residue of a phytol.

Among the amides of caffeic acid, mention may especially be made of the compounds of formula (V):

in which

Z' represents a C₁-C₈, in particular C₆-C₈, alkyl.

The compounds of formula (IV) or (V) are known or can be prepared according to known methods.

The (c) compound may be selected from the group consisting of: quercetin, isoquercetin, rutin, glucosylrutin, and a mixture thereof.

The amount of the (c) compound(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) compound(s) in the composition according to the present invention may be 5% by weight or less, preferably 3% by weight or less, and more preferably 2% by weight or less, relative to the total weight of the composition. The amount of the (c) compound(s) in the composition according to the present invention may range from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, and more preferably from 0.1% to 2% by weight, relative to the total weight of the composition.

[Triglyceride Oil]

The composition according to the present invention comprises (d) at least one oil selected form triglycerides. Thus, a single type of such (d) oil or a combination of different types of such (d) oils may be used.

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

The (d) oil is selected form triglycerides. Thus, the (d) oil may be referred to as (d) triglyceride oil. Triglyceride is an ester derived from glycerol and three fatty acids, and may be referred to as triacylglycerol.

It is preferable that the triglyceride for the (d) oil have at least one unsaturated fatty acid residue. In other words, it is preferable that the triglyceride for the (d) oil be an ester derived from glycerol and at least one unsaturated fatty acid. Thus, the triglyceride for the (d) oil may be (i) an ester derived from glycerol and one unsaturated fatty acid and two saturated fatty acids, (ii) an ester derived from glycerol and two unsaturated fatty acids and one saturated fatty acid, or (iii) an ester derived from three unsaturated fatty acids. If two or more unsaturated fatty acids are used, they may be the same or different. If two saturated fatty acids are used, they may be the same or different.

According to the present invention, "unsaturated fatty acid" means a fatty acid comprising at least one carbon-carbon double or triple bond. They are more particularly fatty acids with long chains, i.e., being able to have 8-32 carbon atoms, preferably 12-26 carbon atoms, and more preferably 14-22 carbon atoms.

The fatty acids can be monounsaturated such as petroselenic acid (C12), palmitoleic acid (C16) and oleic acid (C18), or can be polyunsaturated, i.e., presenting at least two carbon- carbon double bonds, such as linoleic acid (C18) and linolenic acid (C18).

It is more preferable that the triglyceride for the (d) oil have at least one polyunsaturated fatty acid residue. In other words, it is more preferable that the triglyceride for the (d) oil be an ester derived from glycerol and at least one polyunsaturated fatty acid.

The polyunsaturated fatty acid may be selected from ω -3, ω-6, and ω-9 fatty acids, characterized by the closest unsaturation position to the terminal methyl group.

The polyunsaturated fatty acid comprising between 18 and 22 carbon atoms, notably those selected from ω-3 and ω-6 fatty acids, may be more preferable.

Among the polyunsaturated fatty acids of the ω-3 series, mention may be made of a-linolenic acid (18:3, ω-3), stearidonic acid (18:4, ω-3), 5,8,11,14, 17-eicosapentaenoic acid or EPA (20:5, co-3), and 4,7,10,13,16,19-docosahexaenoic acid or DHA (22:6, co-3), docosapentaenoic acid (22,5, co-3), and n-butyl-5,l l,14-eicosatrienonic acid.

Among the polyunsaturated fatty acids of the co-6 series, mention may be made of linolenic acid with 18 carbon atoms and two unsaturations (18:2, co-6), γ-linolenic acid with 18 carbon atoms and three unsaturations (18:3, co-6), dihomogamalinolenic acid with 20 carbon atoms and 3 unsaturations (20:3, co-6), arachidonic acid or 5,8,11,14 eicosatetraenoic acid (20:4, co- 6), and docosatetraenoic acid (22:4, co-6).

As the co-9 fatty acid, mention may be made of mead acid (20:3, co-9).

The polyunsaturated fatty acid may be selected form a-linolenic acid, y-linolenic acid, stearidonic acid, eicosapentaenoic acid, docosahexaenoic acid, mixtures thereof.

The amount of the polyunsaturated fatty acid among the fatty acids forming the fatty acid residues in the triglyceride for the (d) oil may be 10% by weight or more, preferably 30% by weight or more, and more preferably 50% by weight or more, relative to the total weight of the fatty acids.

The weight ratio of the amount of polyunsaturated fatty acid(s)/the amount of monounsaturated fatty acid(s) among the fatty acids forming the fatty acid residues in the triglyceride for the (d) oil may be more than 1.0, preferably more than 1.5, and more preferably more than 2.0.

The (d) triglyceride oil may be selected from plant oils.

For example, the (d) triglyceride oil may be selected from the group consisting of soybean oil, rapeseed oil, cotton seed oil, rice oil, com oil, grape seed oil, sesame oil, linseed oil, and a mixture thereof.

It is preferable that the (d) triglyceride oil be selected from the group consisting of soybean oil, com oil, cotton seed oil, grape seed oil, and a mixture thereof.

The amount of the (d) triglyceride oil(s) in the composition according to the present invention may be 0.1% by weight or more, preferably 0.5% 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 (d) triglyceride oil(s) in the composition according to the present invention may be 20% by weight or less, preferably 15% by weight or less, and more preferably 10% by weight or less, relative to the total weight of the composition.

The amount of the (d) triglyceride oil(s) in the composition according to the present invention may range from 0.1% to 20% by weight, preferably from 0.5% to 15% by weight, more preferably from 1% to 10% by weight, relative to the total weight of the composition.

The (d) triglyceride oil(s) can form a fatty phase of the composition according to the present invention. If the composition according to the present invention is in the form of the O/W type, the (d) triglyceride oil in the composition according to the present invention can form dispersed fatty phases in the O/W type composition.

[Polysaccharide]

The composition according to the present invention may comprise (e) at least one polysaccharide. A single type of polysaccharide may be used, but two or more different types of polysaccharide may be used in combination.

The (e) polysaccharide can form a capsule which can encapsulate (a) at least one retinoid, preferably together with the (d) at least one triglyceride oil, and more preferably together with the (b) at least one lipophilic antioxidant agent and the (d) at least one triglyceride oil. The encapsulation of the (a) at least one retinoid can further reduce the decomposition of the (a) at least one retinoid, or further reduce the change in aspect or color, or the bad smell of the composition according to the present invention. Thus, the capsule can further enhance the stability of the composition according to the present invention.

The capsule of the (e) at least one polysaccharide including the (a) at least one retinoid can be prepared by surrounding or coating the (a) at least one retinoid with at least one layer or film of the (e) at least one polysaccharide. It is preferable that a mixture comprising the (a) at least one retinoid and the (d) at least one triglyceride oil be surrounded or coated by the (e) at least one polysaccharide. It is more preferable that a mixture comprising the (a) at least one retinoid, the (b) at least one lipophilic antioxidant agent and the (d) at least one triglyceride oil be surrounded or coated by the (e) at least one polysaccharide. It is even more preferable that the (a) at least one retinoid be solubilized into the (d) at least one triglyceride oil, and then the (d) at least one triglyceride oil be surrounded or coated by the (e) at least one polysaccharide. The (b) at least one lipophilic antioxidant agent may also be solubilized into the (d) at least one triglyceride oil.

The surrounding step may be performed by any conventional process. For example, it is possible to coextrude (i) a mixture comprising the (a) at least one retinoid and the (d) at least one triglyceride oil together with (ii) the (e) polysaccharide. In this, case, the excluded (i) mixture can form a core, while the (ii) (e) polysaccharide can form a shell. The coextruded core/shell structure can transform into a core/shell particle which corresponds to the capsule. The above (i) mixture may also include the (b) at least one lipophilic antioxidant agent.

The form of the capsule is not limited. For example, the capsule may be in the form of a sphere.

The size of the capsule is not limited. It is possible that the size or the diameter of the capsule may be from 0.1 to 10 mm, preferably from 0.5 to 5 mm, and more preferably from 1 to 3 mm.

The capsule can be dispersed and suspended in the composition according to the present invention. The capsule can provide the composition according to the present invention with unique aspects.

It is preferable that the (e) polysaccharide be selected from polysaccharides derived from plants. In other words, it is preferable that the (e) polysaccharide be of plant origin. On the other hand, it is also preferable that the (e) polysaccharide not be selected from cellulose and derivatives thereof.

According to the present invention, the term "polysaccharides derived from plants" especially means polysaccharides obtained from the plant kingdom (plants or algae), as opposed to polysaccharides obtained via biotechnology, as is the case, for example, for xanthan gum, which is produced especially by fermentation of a bacterium, Xanthomonas campestris.

As examples of polysaccharides of plant origin that may be used according to the present invention, mention may be made especially of: a) algal extracts, such as alginates, carrageenans and agars, and mixtures thereof.

Examples of carrageenans that may be mentioned include Satiagum UTC30® and UTC10® from the company Degussa; an alginate that may be mentioned is the sodium alginate sold under the name Kelcosol® by the company ISP; b) gums, such as guar gum and nonionic derivatives thereof (hydroxypropyl guar), gum arabic, konjac gum or mannan gum, gum tragacanth, ghatti gum, karaya gum or locust bean gum; examples that may be mentioned include the guar gum sold under the name Jaguar HP105® by the company Rhodia; the mannan and konjac gum® (1% gluconomannan) sold by the company GfN; c) modified or unmodified starches, such as those obtained, for example, from cereals, for instance wheat, com or rice, from legumes, for instance blonde pea, from tubers, for instance potato or cassava, and tapioca starches; dextrins, such as com dextrins; examples that may especially be mentioned include the rice starch Remy DR I® sold by the company Remy; the com starch B® from the company Roquette; the potato starch modified with 2-chloroethylaminodipropionic acid neutralized with sodium hydroxide, sold under the name Structure Solanace® by the company National Starch; the native tapioca starch powder sold under the name Tapioca pure® by the company National Starch; d) dextrins, such as the dextrin extracted from com under the name Index® from the company National Starch; and mixtures thereof.

Preferably, the (e) polysaccharide be chosen from algal extracts.

The algal extracts may be chosen from alginates, carrageenans and agars, and mixtures thereof. Preferably, alginates or agars, or mixtures thereof, may be used.

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

On the other hand, the amount of the (e) polysaccharide(s) in the composition according to the present invention may be 5% by weight or less, preferably 2% by weight or less, and more preferably 1% by weight or less, relative to the total weight of the composition.

The amount of the (e) polysaccharide(s) in the composition according to the present invention may range from 0.001% to 5% by weight, preferably from 0.005% to 2% by weight, more preferably from 0.01% to 1% by weight, relative to the total weight of the composition. [Chelating Agent]

The composition according to the present invention may comprise (f) at least one chelating agent if it comprises no (e) polysaccharide. A single type of chelating agent may be used, but two or more different types of chelating agents may be used in combination.

As the (f) chelating agent, mention may be made of

(i) aminocarboxylic acids such as the compounds having the following INCI name: diethylenetriaminepentaacetic acid (DTPA), ethylenediaminedisuccinic acid (EDDS) and trisodium ethylenediamine disuccinate such as Octaquest E30 from Octel, ethylenediaminetetraacetic acid (EDTA), ethylenediamine-N,N'-diglutaric acid (EDDG), glycinamide-N,N'-disuccinic acid (GADS), 2-hydroxypropylenediamine- N,N'-disuccinic acid (HPDDS), ethylenediamine-N,N'-bis(ortho- hydroxyphenylacetic acid) (EDDHA), N,N'-bis(2-hydroxybenzyl)ethylenediamine- N,N'-diacetic acid (HBED), nitrilotriacetic acid (NTA), methylglycine diacetic acid (MGDA), N-2-hydroxyethyl-N,N-diacetic acid and glyceryl imino diacetic acid (as described in documents EP-A-317 542 and EP-A-399 133), iminodiacetic acid-N-2- hydroxypropyl sulfonic acid and aspartic acid N-carboxymethyl N-2-hydroxypropyl- 3-sulfonic acid (as described in EP-A-516 102), beta-alanine-N,N'-diacetic acid, aspartic acid-N,N'-diacetic acid and aspartic acid-N-monoacetic acid (described in EP-A-509 382), chelating agents based on iminodisuccinic acid (IDS A) (as described in EP-A-509 382), ethanoldiglycine acid, phosphonobutane tricarboxylic acid, such as the compound sold by Bayer under the reference Bayhibit AM, tetrasodium glutamate diacetate (GLDA) such as Dissolvine GL38 or 45 S from Akzo Nobel,

(ii) chelating agents based on mono- or polyphosphonic acid, such as the compounds having the following INCI name: diethylenetriaminepenta(methylenephosphonic acid) (DTPMP), ethane- l-hydroxy-l,l,2-triphosphonic acid (E1HTP), [0263]ethane- 2-hydroxy-l,l,2-triphosphonic acid (E2HTP), ethane- l-hydroxy-l,l-diphosphonic acid (EHDP), ethane- 1,1,2-triphosphonic acid (ETP), ethylenediaminetetramethylenephosphonic acid (EDTMP), and hydroxy ethane- 1,1- diphosphonic acid (HEDP), and

(iii) chelating agents based on polyphosphoric acid, such as the compounds having the following INCI name: sodium tripolyphosphate (STP), tetrasodium diphosphate, hexametaphosphoric acid, sodium metaphosphate, phytic acid, salts and derivatives thereof, and mixtures thereof.

It is preferable that the (f) chelating agent be biodegradable. In this sense, EDTA which is not biodegradable, is not preferable as the (f) chelating agent. Thus, it is preferable not to use EDTA as the (f) chelating agent. Furthermore, it is preferable that the composition according to the present invention is free from EDTA.

The term “free from” here means that the composition according to the present invention may contain a limited amount of EDTA. However, it is preferable that the amount of EDTA be limited such that it is less than 1% by weight, more preferably less than 0.1% by weight, and even more preferably less than 0.01% by weight, relative to the total weight of the composition. It is most preferable that the composition according to the present invention comprise no EDTA. It is more preferable that the (f) chelating agent be risodium ethylenediamine disuccinate.

The amount of the (f) chelating agent(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.

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

The amount of the (f) chelating agent(s) in the composition according to the present invention may range from 0.001% to 3% by weight, preferably from 0.005% to 2% by weight, more preferably from 0.01% to 1% by weight, relative to the total weight of the composition.

[Water]

The composition according to the present invention may comprise water.

The water can form an aqueous phase of the composition according to the present invention.

If the composition according to the present invention is in the form of the O/W type, the water in the composition according to the present invention can form a continuous aqueous phase in the O/W type composition.

The amount of the water in the composition according to the present invention may be 50% by weight or more, preferably 55% by weight or more, and more preferably 60% by weight or more, relative to the total weight of the composition.

On the other hand, the amount of the water in the composition according to the present invention may be 90% by weight or less, preferably 85% by weight or less, and more preferably 80% by weight or less, relative to the total weight of the composition.

The amount of water in the composition according to the present invention may range from 50% to 90% by weight, preferably from 55% to 85% by weight, more preferably from 60% to 80% 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 which is different from polyphenol. 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, caprylylglycol, 1,3- propanediol, 1,5-pentanediol, polyethyleneglycol (5 to 50 ethyleneoxide groups), and mixtures thereof.

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 35% by weight or less, preferably 30% by weight or less, and more preferably 25% 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 35% by weight, and preferably from 0.05% to 30% by weight, such as from 0.1% to 25% 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 60% by weight or less, preferably 55% by weight or less, and more preferably 50% 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 60 by weight, preferably from 0.1% to 55% by weight, and more preferably from 1% to 50% 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, cationic, amphoteric, and nonionic surfactants, hydrophilic antioxidants, coloring agents, thickeners, sequestering agents, fragrances, dispersing agents, conditioning agents, film-forming agents, preservatives, copreservatives, and mixtures thereof, except for the ingredients as explained above. [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 form of the composition according to the present invention is not particularly limited, and may take various forms such as an emulsion (O/W or W/O form), an aqueous gel, an aqueous solution, or the like.

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

The O/W architecture or structure, which consists of fatty 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.

[Process and Use]

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 such as skin, comprising the step of applying the composition according to the present invention to the keratin substance.

The composition according to the present invention may be used as an anti-aging, antiwrinkling, or turnover promoting product for a keratinous substance such as skin. In particular, the composition according to the present invention may be used as an antiwrinkling skin cosmetic product.

Another aspect of the present invention relates to a use of:

(b) at least one lipophilic antioxidant agent;

(c) at least one compound which is capable of providing a solution thereof with a transmittance of 10% or less, preferably 5% or less, and more preferably 2% or less, for light with a wavelength of from 290 to 420 nm, along a light path length of 10 mm, the concentration of the compound in the solution being 0.9% by weight relative to the total weight of the solution; and

(d) at least one oil selected form triglycerides, preferably triglycerides having at least one unsaturated fatty acid residue, and more preferably triglycerides having at least one polyunsaturated fatty acid residue, for the manufacture of a stable composition comprising the (a) at least one retinoid, preferably stable for both under light exposure and different temperature conditions, or for reducing the decomposition of the (a) at least one retinoid in a composition comprising the

(a) at least one retinoid, both under light exposure and at high temperature, wherein the composition comprises (e) at least one optional polysaccharide, preferably selected from polysaccharides derived from plants, and more preferably selected from algal extracts, and if the composition does not comprise the (e) at least one polysaccharide, the composition comprises (f) at least one chelating agent, preferably a biodegradable chelating agent, and more preferably trisodium ethylenediamine disuccinate.

Another aspect of the present invention also relates to a process for preparing a stable composition comprising (a) at least one retinoid, preferably stable for both under light exposure and different temperature conditions, or reducing the decomposition of (a) at least one retinoid in a composition comprising the (a) at least one retinoid, both under light exposure and at high temperature, comprising a step or steps of adding:

(b) at least one lipophilic antioxidant agent;

(e) at least one optional polysaccharide, preferably selected from polysaccharides derived from plants, and more preferably selected from algal extracts to the composition, wherein if the (e) at least one polysaccharide is not added, the process further comprises a step of adding (f) at least one chelating agent, preferably a biodegradable chelating agent, and more preferably trisodium ethylenediamine disuccinate.

In the above aspects, it is preferable that the (a) at least one retinoid be encapsulated by the (e) at least one polysaccharide.

It is more preferable that a mixture comprising the (a) at least one retinoid and the (d) at least one triglyceride oil be encapsulated by the (e) at least one polysaccharide.

It is even more preferable that a mixture comprising the (a) at least one retinoid, the (b) at least one lipophilic antioxidant agent, and the (d) at least one triglyceride oil be encapsulated by the (e) at least one polysaccharide.

The above explanations regarding the ingredients (a) to (f), as well as the optional ingredients, for the composition according to the present invention can apply to those for the above uses and processes according to the present invention. The explanations regarding the preparation and forms of the composition according to the present invention can also apply to those of the composition recited in the above uses and processes.

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 1-4]

The following compositions according to Example 1 and Comparative Examples 1-4 in the form of O/W emulsions, shown in Table 1 , were prepared by mixing the ingredients shown in Table 1.

The preparations of the O/W emulsions (Example 1 and Comparative Examples 1-4) were performed as follows:

(1) mixing the ingredients of Phase B at 75-80 °C to form a uniform mixture of Phase B;

(2) cooling the mixture obtained by the above step (1) to a room temperature;

(3) adding the ingredients of Phase A to the uniform mixture of Phase B at room temperature to form a uniform mixture of Phase (A+B);

(4) mixing the ingredients of Phase C with a homogenizer at 75-80 °C to form a uniform mixture of Phase C;

(5) mixing the ingredients of Phase D at room temperature to form a uniform mixture of Phase D;

(6) mixing the uniform mixture of Phase (A+B), the uniform mixture of Phase C and the uniform mixture of Phase D; and

(7) homogenizing and cooling the mixture obtained by the above step (6) to room temperature.

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

Table 1

[Evaluations]

(Thermo-Stability)

Retinol Residual Rate:

Each of the compositions according to Example 1 and Comparative Examples 1-4 was filled into a glass bottle and was held under temperature conditions of 45°C for 2 months. The residual rate (%) of retinol after storage at 45 °C for 2 months was measured by HLPC and calculated as a function of the initial % (24h after production) measured by HPLC. The retinol residual rate (%) thus calculated for each composition was evaluated in accordance with the following criteria.

Very Good: 85 ≤ Good: 80 ≤ and < 85 Poor: 70 ≤ and < 80 Very Poor: < 70

The results are shown in Table 1.

Visual Observation:

Each of the compositions according to Example 1 and Comparative Examples 1-4 was filled into four glass bottles, and each of the glass bottles was held under temperature conditions of 4°C, 25°C, 37°C, and 45°C, respectively, for 2 months.

Each glass bottle was then investigated for the degree of change (in terms of aspect, color, and odor), and evaluated by the following criteria.

Very Good: Almost the same condition as production.

Good: Little change in aspect, color, or odor was observed.

Poor: Change in aspect (separation or creaming), color (yellowing or browning), or odor (bad smell) could be clearly observed.

Very Poor: Change in aspect (separation or creaming), color (yellowing or browning) or odor (bad smell) could be remarkably noticed.

The results are shown in Table 1.

(Photo-Stability)

Retinol Residual Rate:

Each of the compositions according to Example 1 and Comparative Examples 1-4 was filled into a glass bottle and was tested by Sun Test* (24h). The residual rate (%) of retinol after Sun Test was measured by HLPC and calculated as a function of the initial % (24h after production) measured by HPLC. The retinol residual rate (%) thus calculated for each composition was evaluated in accordance with the following criteria.

Very Good: 85 ≤

Good: 80 ≤ and < 85 Poor: 70 ≤ and < 80

Very Poor: < 70

* Sun Test

The glass bottle was exposed to artificial sun light by using SUNTEST CPS+ (Atras) under the following conditions: Irradiance; 765 W/m², Temperature; 25 °C, and Duration of Test; 24 hours

The results are shown in Table 1.

Visual Observation:

Each of the compositions according to Example 1 and Comparative Examples 1 -4 was filled into a glass bottle, and the glass bottle was subjected to the above Sun Test.

Very Good: Almost the same condition as production.

Good: Little change in aspect, color, or odor was observed.

The results are shown in Table 1.

(Results)

The composition according to Example 1 which included the ingredients (a) to (d) explained above (the optional ingredient (e) was absent) was stable both under light exposure and different temperatures such that the conditions of the composition did not substantially change. Also, the ingredient (a) in the composition according to Example 1 was maintained at a sufficient residual rate even both under light exposure and at high temperature.

The composition according to Comparative Example 1 which did not include the ingredient (d) could not maintain the ingredient (a) at a sufficient residual rate at the high temperature.

The composition according to Comparative Example 2 which did not include the ingredient (b) could not maintain the ingredient (a) at a sufficient residual rate at the high temperature.

The composition according to Comparative Example 3 which did not include the ingredient (f) could not maintain the ingredient (a) at a sufficient residual rate at the high temperature.

The composition according to Comparative Example 4 which did not include the ingredient (c) could not maintain the ingredient (a) at a sufficient residual rate against light. [Examples 2-5 and Comparative Examples 5-7]

The following compositions according to Examples 2-5 and Comparative Examples 5-7 in the form of encapsulated O/W gel type dispersions, shown in Table 2, were prepared by mixing the ingredients shown in Table 2.

The preparations of the encapsulated O/W gel type dispersions according to Examples 2-5 and Comparative Examples 5-7 were performed as follows:

(2) cooling the mixture obtained by the above step (1) to a room temperature;

(6) adding the uniform mixture of Phase D to the uniform mixture of Phase C at room temperature to form a uniform mixture of (C+D);

(7) mixing the ingredients of Phase E with a homogenizer at 80-90 °C to form a uniform mixture of Phase E;

(8) coextruding the uniform mixture of Phase (A+B) and the uniform mixture of Phase E by encapsulating the former with the latter to prepare capsules in which the uniform mixture of Phase (A+B) is coated and encapsulated with the uniform mixture of Phase E; and

(9) adding the capsules obtained by the above step (8) to the uniform mixture of Phase (C+D) at a room temperature.

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

[Evaluations]

(Thermo-Stability)

Retinol Residual Rate:

Each of the compositions according to Examples 2-5 and Comparative Examples 5-7 was filled into a glass bottle and was held under temperature conditions of 45°C for 2 months. The residual rate (%) of retinol after storage at 45°C for 2 months was measured by HLPC and calculated as a function of the initial % (24h after production) measured by HPLC. The retinol residual rate (%) thus calculated for each composition was evaluated in accordance with the following criteria.

Very Good: 85 ≤ Good: 80 ≤ and < 85 Poor: 70 ≤ and < 80 Very Poor: < 70

The results are shown in Table 2.

Visual Observation:

Each of the compositions according to Examples 2-5 and Comparative Examples 5-7 was filled into four glass bottles, and each of the glass bottles was held under temperature conditions of 4°C, 25°C, 37°C, and 45°C, respectively, for 2 months.

Very Good: Almost the same condition as production.

Good: Little change in aspect, color, or odor was observed.

The results are shown in Table 2.

(Photo- Stability)

Retinol Residual Rate:

Each of the compositions according to Examples 2-5 and Comparative Examples 5-7 was filled into a glass bottle and was tested by Sun Test* (24h). The residual rate (%) of retinol after Sun Test was measured by HLPC and calculated as a function of the initial % (24h after production) measured by HPLC. The retinol residual rate (%) thus calculated for each composition was evaluated in accordance with the following criteria.

Very Good: 85 ≤

Good: 80 ≤ and < 85 Poor: 70 ≤ and < 80

Very Poor: < 70

*Sun Test

The glass bottle was exposed to artificial sun light by using SUNTEST CPS+ (Atras) under the following conditions:

Irradiance; 765 W/m²,

Temperature; 25°C, and

Duration of Test; 24 hours

The results are shown in Table 2.

Visual Observation:

Each of the compositions according to Examples 2-5 and Comparative Examples 5-7 was filled into a glass bottle, and the glass bottle was subjected to the above Sun Test.

Very Good: Almost the same condition as production.

Good: Little change in aspect, color, or odor was observed.

The results are shown in Table 2.

(Results)

The composition according to Example 2 which included the ingredients (a) to (e) explained above was stable both under light exposure and different temperatures such that the conditions of the composition did not substantially change. Also, the ingredient (a) in the composition according to Example 2 was maintained at a sufficient residual rate even both under light exposure and at high temperature.

The compositions according to Examples 3 and 4 each of which included a single ingredient as the ingredient (b) were also stable both under light exposure and different temperatures such that the conditions of the compositions did not substantially change. Also, the ingredient (a) in the compositions according to Examples 3 and 4 was maintained at a sufficient residual rate even both under light exposure and at high temperature.

The composition according to Example 5 which included the ingredient (e) and did not include the ingredient (f) was also stable both under light exposure and different temperatures such that the conditions of the composition did not substantially change. Also, the ingredient (a) in the composition according to Example 5 was maintained at a sufficient residual rate even both under light exposure and at high temperature. The composition according to Comparative Example 5 which did not include the ingredient (d) could not maintain the ingredient (a) at a sufficient residual rate at the high temperature.

The composition according to Comparative Example 6 which did not include the ingredient

(b) could not maintain the ingredient (a) at a sufficient residual rate at the high temperature.

The composition according to Comparative Example 7 which did not include the ingredient

(c) could not maintain the ingredient (a) at a sufficient residual rate against light.

Claims

1. A composition, preferably a cosmetic composition, and more preferably a skin cosmetic composition, comprising:

(a) at least one retinoid;

(b) at least one lipophilic antioxidant agent;

2. The composition according to Claim 1, wherein the (a) retinoid is retinol.

3. The composition according to Claim 1 or 2, wherein the amount of the (a) retinoid(s) in the composition ranges from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, and more preferably from 0.1% to 1% by weight, relative to the total weight of the composition.

4. The composition according to any one of Claims 1 to 3, wherein the (b) lipophilic antioxidant agent is selected from biodegradable lipophilic antioxidant agents, and preferably tocopherol, pentaerythrityl tetra-di-t-butyl hydroxyhydrocinnamate, and a mixture thereof.

5. The composition according to any one of Claims 1 to 4, wherein the amount of the (b) lipophilic antioxidant agent(s) in the composition ranges from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, and more preferably from 0.1% to 1% by weight, relative to the total weight of the composition.

6. The composition according to any one of Claims 1 to 5, wherein the (c) compound is selected from polyphenols, preferably quercetin, isoquercetin, rutin, glucosylrutin, and a mixture thereof.

7. The composition according to any one of Claims 1 to 6, wherein the amount of the (c) compound in the composition ranges from 0.01% to 5% by weight, preferably from 0.05% to 3% by weight, and more preferably from 0.1% to 2% by weight, relative to the total weight of the composition.

8. The composition according to any one of Claims 1 to 7, wherein the (d) oil is selected from plant oils, preferably from the group consisting of soybean oil, com oil, cotton seed oil, grape seed oil, and a mixture thereof.

9. The composition according to any one of Claims 1 to 8, wherein the amount of the (d) oil in the composition ranges from 0.1% to 20% by weight, preferably from 0.5% to 15% by weight, and more preferably from 1% to 10% by weight, relative to the total weight of the composition.

10. The composition according to any one of Claims 1 to 9, wherein the (e) polysaccharide is selected from agar, alginate, carrageenan and a mixture thereof.

11. The composition according to any one of Claims 1 to 10, wherein the amount of the (e) polysaccharide(s) in the composition ranges from 0.001% to 5% by weight, preferably from 0.005% to 2% by weight, and more preferably from 0.01% to 1% by weight, relative to the total weight of the composition.

12. The composition according to any one of Claims 1 to 11, wherein the composition comprises no (e) polysaccharide, and comprises (f) at least one chelating agent, preferably a biodegradable chelating agent, and more preferably trisodium ethylenediamine disuccinate.

13. The composition according to Claim 12, wherein the amount of the (f) chelating agent(s) in the composition ranges from 0.001% to 3% by weight, preferably from 0.005% to 2% by weight, and more preferably from 0.01% to 1% by weight, relative to the total weight of the composition.

14. The composition according to any one of Claims 1 to 13, wherein the composition is in the O/W form, preferably an O/W emulsion or an O/W dispersion, and more preferably an O/W gel emulsion or an O/W gel dispersion.

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