CN113226253A - Composition for lightening or whitening keratin materials - Google Patents

Abstract

Provided herein is a composition for lightening or whitening keratin materials in the form of an emulsion comprising an oil phase dispersed in an aqueous phase and comprising: (i) at least one antioxidant or skin whitening active ingredient selected from phenolic compounds; and (ii) at least one hydrotrope; and (iii) at least one polymer derived from 2-acrylamidomethylpropanesulfonic acid. It also relates to a cosmetic process for lightening or whitening keratin materials, in particular human skin.

Description

Composition for lightening or whitening keratin materials

Technical Field

The present invention relates to cosmetic compositions. In particular, the present invention relates to a composition for lightening or whitening keratin materials, in particular human skin.

Background

Human skin color depends on various factors, and in particular on the season, race, and gender of the year; it is determined primarily by the nature and concentration of melanin produced by melanocytes. Melanocytes are specialized cells that synthesize melanin by means of specific organelles (melanosomes). Furthermore, at various stages in their life, certain individuals develop dark and/or colored spots on the skin, and more particularly on the hands, which lead to skin non-uniformity.

For various reasons, in particular those linked to a higher comfort of use (softness, emolliency, etc.), the compositions currently used for caring for and/or making up keratin materials, in particular the skin, are generally in the form of an oil-in-water (O/W) emulsion consisting of an aqueous dispersed continuous phase and an oily dispersed discontinuous phase; or in the form of a water-in-oil (W/O) type emulsion consisting of an oily dispersed continuous phase and an aqueous dispersed discontinuous phase.

O/W emulsions are the most sought after emulsions in the cosmetic field, since they comprise an aqueous phase as the external phase, which makes them have a fresher, less greasy and lighter feel when applied to the skin than W/O emulsions.

However, due to their natural characteristics, conventional oil-in-water emulsions are not entirely satisfactory, especially with respect to lightening or whitening the skin.

Efforts have been made to incorporate silicone, styrene-type copolymers in combination with pigments and whitening actives into oil-in-water emulsions. However, the inventors have found that it is difficult to obtain compositions which have a good lightening or whitening effect on the skin, while at the same time not affecting the comfort of use.

Efforts have also been made to incorporate skin whitening ingredients into oil-in-water emulsions. Unfortunately, such ingredients make the resulting emulsion sticky, thereby somewhat deteriorating the feel of the emulsion.

Thus, there is a need to formulate compositions to overcome the difficulties mentioned above.

In particular, there is a need to formulate compositions in the form of emulsions comprising an oil phase dispersed in an aqueous phase, having a lightening or whitening effect on keratin materials, while maintaining a good feel.

Summary of The Invention

The inventors have found that such a need can be met by the present invention.

Thus, according to one aspect, the present invention relates to a composition for lightening or whitening keratin materials in the form of an emulsion comprising an oily phase dispersed in an aqueous phase and comprising:

(i) at least one skin lightening or whitening active ingredient selected from flavonoids;

(ii) at least one hydrotrope; and

(iii) at least one polymer derived from 2-acrylamidomethylpropanesulfonic acid.

The composition according to the invention is advantageous in several respects.

Firstly, the compositions according to the invention have a lightening or whitening effect on keratin materials, in particular human skin.

In particular, the "lightening and whitening effect" according to the invention refers to a lightening or whitening effect on keratin materials, which is shown by the bioavailability of the skin lightening or whitening active ingredient 16 hours after application of the composition of the invention on a substrate.

In addition, the compositions of the present invention exhibit good feel, such as moisturization (hydration), nutrition, softness, and/or resistance to dullness.

The composition of the invention has a viscosity of less than 50UD (units of deviation), preferably from 17UD to 35UD, as measured at 25 ℃ using a Rheomat 180 viscometer equipped with a spindle M2 rotating at 200 rpm.

According to another aspect, the present invention also relates to a cosmetic process for lightening or whitening keratin materials, in particular human skin, comprising the step of applying to the keratin materials a composition according to the invention.

For the purposes of the present invention, the term "keratin materials" is intended to cover the skin, mucous membranes (for example the lips), nails of humans. Human skin, especially facial skin, is most particularly contemplated according to the present invention.

Other objects and features, aspects and advantages of the present invention will become even more apparent upon reading the following detailed description and examples.

Detailed Description

Hereinafter and unless otherwise indicated, the upper and lower limits of the range of values are included in the range, especially in the expressions "between … …" and "range from … … to … …".

Further, the expression "at least one" used in the present specification is equivalent to the expression "one or more".

Throughout this application, the term "comprising" should be interpreted as encompassing all of the specifically mentioned features as well as optional, additional, unspecified features. As used herein, the use of the term "comprising" also discloses embodiments in which no feature other than the specifically mentioned feature is present (i.e., "consisting of … …").

According to one aspect, the present invention relates to a composition for lightening or whitening keratin materials, in the form of an emulsion comprising an oily phase dispersed in an aqueous phase, and comprising:

(i) at least one skin lightening or whitening active ingredient selected from flavonoids;

(ii) at least one hydrotrope; and

(iii) at least one polymer derived from 2-acrylamidomethylpropanesulfonic acid (hereinafter referred to as AMPS polymer).

Antioxidant or skin whitening active ingredient

The composition according to the invention comprises at least one skin lightening or whitening active ingredient selected from flavonoids.

Flavonoids

Flavonoids are a specific group of polyphenols, and the most abundant group of polyphenolic compounds, constituting about two thirds of the total phenols consumed in the feed. Flavonoids are further classified into chalcones, flavones, flavanones, flavanols, flavonols, flavanonols, isoflavonoids, neoflavonoids, catechins, anthocyanidins, and tannins according to chemical structure. Over 4,000 flavonoids have been identified, many of which are present in fruits, vegetables and beverages (tea, coffee, beer, wine and fruit drinks). Flavonoids have been reported to have antiviral, antiallergic, antiplatelet, anti-inflammatory, antitumor and antioxidant activities. Flavonoids protect lipids and live cell components from damaging oxidative stress by effectively scavenging free radicals.

Preferably, the flavonoid used is a flavone.

Baicalin (component of the Chinese herbal medicine scutellaria baicalensis (Huang-chi)) is a flavone (a flavonoid). It is an effective antioxidant showing an effective action against oxidative stress diseases, inflammation, allergy, cancer, bacterial infection and the like.

Baicalin is found in several species of the genus Scutellaria (Scutellaria), including Scutellaria (Scutellaria basicalensis) and Scutellaria laterali (Scutellaria lateriflora). Scutellaria baicalensis (Scutellaria galericulata) leaves present at 10mg/g baicalin. Baicalin is also present in bark isolates of the Oroxylum indicum (Oroxylum indicum) tree.

In one embodiment according to the present invention, baicalin is used in the form of an extract of the root of Scutellaria baicalensis (Scutellaria baicalensis).

Preferably, the flavonoid is present in an amount ranging from 0.1 wt.% to 2 wt.%, preferably from 0.1 wt.% to 1 wt.%, more preferably from 0.1 wt.% to 0.5 wt.%, relative to the total weight of the composition.

Hydroxylated diphenylmethane derivatives

According to a preferred embodiment of the present invention, the composition further comprises at least one hydroxylated diphenylmethane derivative as skin lightening or whitening ingredient.

The hydroxylated diphenylmethane derivatives which can be used in the compositions of the invention are preferably selected from those of formula (I) below:

wherein:

R₁selected from the group consisting of a hydrogen atom, a methyl group, a saturated or unsaturated, linear or branched hydrocarbon chain containing from 2 to 4 carbon atoms, -an OH group and a halogen,

R₂selected from the group consisting of hydrogen atoms, methyl groups and radicals containingA saturated or unsaturated, linear or branched hydrocarbon chain having 2 to 5 carbon atoms,

R₃selected from methyl or a saturated or unsaturated, linear or branched hydrocarbon chain containing from 2 to 5 carbon atoms,

R₄and R₅Independently of one another, from a hydrogen atom, a methyl group, a saturated or unsaturated, linear or branched hydrocarbon chain containing from 2 to 5 carbon atoms, -an OH group or a halogen.

Relative to the bond formed with the carbon linking the two aromatic nuclei to each other, -OH, R₁、R₄And R₅The groups may be in the ortho, meta or para positions.

According to a preferred embodiment of the invention, compounds of formula (I) are used, wherein:

-R₁、R₂、R₄and R₅Represents a hydrogen atom;

-R₃is methyl;

the-OH groups are located in the ortho and para positions relative to the bonds formed with the carbon linking the two aromatic nuclei to each other.

This compound corresponds to the following formula (II):

referred to as 4- (1-phenylethyl) -1, 3-benzenediol or 4- (1-phenylethyl) -1, 3-dihydroxybenzene or alternatively phenylethyl resorcinol or phenylethyl benzenediol or styryl resorcinol. This compound has CAS number 85-27-8. Such compounds are known under the name Symwhite by the company Symrise

Or Bio 377.

If present, the hydroxylated diphenylmethane derivative is present in an amount in the range of from 0.1 wt.% to 2 wt.%, more preferably from 0.1 wt.% to 1 wt.%, even more preferably from 0.1 wt.% to 0.5 wt.%, relative to the total weight of the composition.

Hydrotropic agent

The composition according to the invention comprises at least one hydrotrope.

A single type of hydrotrope can be used, but two or more different types of hydrotropes can be used in combination.

Hydrotropes (or hydrotropes) can be a diverse class of compounds characterized by an amphiphilic molecular structure and the ability to significantly increase the solubility of poorly soluble organic molecules in water. Many hydrotropes have aromatic structures with ionic moieties, while some of them are linear alkyl chains (as listed in the table below). Although hydrotropes are clearly similar to surfactants and have the ability to reduce surface tension, their small hydrophobic units and relatively short alkyl chains distinguish them as a separate class of amphiphiles.

Common hydrotropic molecules include: sodium 1, 3-benzenedisulfonate, sodium benzoate, sodium 4-pyridinecarboxylate, sodium salicylate, sodium benzenesulfonate, caffeine, sodium p-toluenesulfonate, sodium butylmonoglycol sulfate, 4-aminobenzoate, sodium cumene sulfonate, N, n-diethylnicotinamide, N-pyridylmethylnicotinamide, N-allylnicotinamide, 2-methacryloyloxyethylphosphonic acid choline, resorcinol, butylurea, pyrogallol, N-pyridylmethylacetamide 3.5, procaine hydrochloride, proline hydrochloride, nicotinamide, pyridine, 3-pyridylmethylamine, sodium ibuprofen, sodium xylenesulfonate, ethyl carbamate, pyridoxal hydrochloride, sodium benzoate, 2-pyrrolidone, ethylurea, N-dimethylacetamide, N-methylacetamide and isoniazid. Hydrotropes can be found in Lee J.et al, "Hydrotropic solution of Paclixel: Analysis of chemical structures for Hydrotropic Property", Pharmaceutical Research, Vol.20, No. 7, 2003 and Hodgon T.K., Kaler E.W., "Hydrotropic Solutions", Current Opinion in Colloid and IInterface Science,12,1211-128, 2007.

Cosmetically acceptable hydrotropes are the preferred hydrotropes that can be used in cosmetic compositions. Although hydrotropes represent a large class of molecules used in various fields, cosmetic applications are limited due to safety and tolerability limitations. Preferred hydrotropes in cosmetics are listed below:

the suitability of a hydrotrope for use in a cosmetic composition can be determined using tests known in the art for determining the effect of a compound on skin as well as bioavailability methods.

The advantage of using a hydrotrope is that once a stable solution is obtained, further dilution does not affect the stability of the solution. This is quite different from organic solvents that are commonly used to increase the water solubility of active substances. In general, aqueous dilution of organic solvents with pre-dissolved active substances leads to crystallization or precipitation.

The hydrotrope can have the following logP: from-0.7 to 6, preferably from-0.7 to 1.0, preferably from-0.5 to 0.7, for nonionic hydrotropes and from-0.7 to 5.5 for ionic hydrotropes (e.g. acidic hydrotropes).

The formulator will adjust the pH with a hydrotrope to optimize clarity.

The logP value is the base 10 logarithm of the apparent octan-1-ol/water partition coefficient. The logP values are known and determined by standard tests that determine the concentration of compound (c) in oct-1-ol and water. logP can be calculated according to the method described by Meylan and Howard in the article Atom/Fragment restriction method for affecting and water partitioning influences, J.Pharm.Sci.,84:83-92, 1995. This value can also be calculated using many commercially available software packages that determine logP as a function of molecular structure. By way of example, Epiwin software from the United States Environmental Agency may be mentioned.

This value can be calculated using, inter alia, ACD (advanced Chemistry development) Solaris software V4.67; they are also available from expanding QSAR: hydrobic, electronic and steric constantans (ACS technical reference, 1995). There is also an internet site that provides estimates (address: http:// esc. sysres. com/interkow/kowdemo. htm).

Preferably, the hydrotrope is selected from oxothiazolidinecarboxylic acids; vitamin B3 and derivatives thereof, preferably niacinamide; xanthine bases, preferably caffeine; camphorbenzammonium methylsulfate, ellagic acid, hydroxyphenoxypropionic acid, diethyl 2, 4-pyridinedicarboxylate (diethyl nicotinate), terephthalylidene dicamphor sulfonic acid, ferulic acid, salicylic acid, phloretin, acetyltrifluoromethylphenylvalylglycine, resveratrol, 4-butylresorcinol, apigenin, phenethylresorcinol, prasterone, benzophenone-3, butylmethoxydibenzoylmethane, octanoylsalicylic acid, ethylhexyl salicylate, and jasmonic acid derivatives, preferably sodium tetrahydrojasmonate. Vitamin B3 and its derivatives, xanthine bases (e.g. caffeine) and jasmonic acid derivatives, described in more detail below, are more preferred.

(vitamin B3 and derivatives thereof)

Vitamin B3, also known as vitamin PP, is a compound of formula (III):

wherein R may be-CONH₂(nicotinamide), -COOH (nicotinic acid or nicotinic acid), or CH₂OH (nicotinyl alcohol), -CO-NH-CH₂-COOH (nicotinic acid) or-CO-NH-OH (nicotinic hydroxamic acid). Nicotinamide is preferred.

Vitamin B3 derivatives that may be mentioned include, for example, nicotinates, such as tocopherol nicotinate; by substitution of-CONH₂The hydrogen group of (a) is derived from an amide of nicotinamide; products from reactions with carboxylic acids and amino acids; esters of nicotinyl alcohol and carboxylic acids such as acetic acid, salicylic acid, glycolic acid or palmitic acid.

The following derivatives may also be mentioned: 2-chloronicotinamide, 6-methylnicotinamide, 6-aminonicotinamide, N-methylnicotinamide, N-dimethylnicotinamide, N- (hydroxymethyl) nicotinamide, quinolinic acid imide, nicotinanilide, N-benzylnicotinamide, N-ethylnicotinamide, Nifenazone, nicotinaldehyde (nicotinaldehyde), isonicotinic acid, methylisonicotinic acid, thionicotinamide, niaziamide, 2-mercaptonicotinic acid, Nikemor and Nipramizine, methyl nicotinate and sodium nicotinate.

Other vitamin B3 derivatives that may also be mentioned include inorganic salts thereof, such as chloride, bromide, iodide or carbonate; and organic salts thereof, such as salts obtained by reaction with carboxylic acids, for example, acetates, salicylates, glycolates, lactates, malates, citrates, mandelates, tartrates and the like.

Preferably, vitamin B3 or a derivative thereof has a log P of-0.7 to 6, preferably-0.6 to 5, more preferably-0.5 to 4.

(xanthine base)

Among the xanthine bases which can be used according to the invention, mention may be made of: caffeine, theophylline, theobromine, theophylline acetic acid, xanthinol nicotinate, dineophylline, diprophylline, etatheophylline and its derivatives, etoxytheophylline, propoxyphylline, pentoxifylline (pentophylline), propentofylline, pyridophylline and bamifylline, this list being non-limiting.

Preferably, the xanthine base is selected from caffeine, theophylline, theobromine, theophylline acetic acid and mixtures thereof. These xanthine bases are known as inhibitors of phosphodiesterase, an enzyme responsible for the degradation of cAMP. By increasing the intracellular level of cAMP, these xanthines promote lipolytic activity and thus constitute a leading slimming agent.

As examples of plant extracts containing xanthine bases, mention may be made in particular of the extracts of tea, coffee, guarana, yerba mate and cola nuts, this list being non-limiting.

Preferably, the xanthine base has a log P of-0.7 to 6, preferably-0.6 to 5, more preferably-0.5 to 4, and even more preferably-0.3 to 2.

(jasmonic acid derivative)

Jasmonic acid derivatives are compounds selected from those corresponding to the following formula (IV):

wherein: r₁Represents COOR₃Group, R₃Represents a hydrogen atom or C optionally substituted by one or more hydroxyl groups₁-C₄An alkyl group; r₂Represents a saturated or unsaturated hydrocarbon group which is linear and has 1 to 18 carbon atoms, or which is branched or cyclic and has 3 to 18 carbon atoms; and their optical isomers, and corresponding salts.

Preferably, R₁Represents a group selected from: -COOH, -COOMe (Me: methyl), -COO-CH₂-CH₃、-COO-CH_2--CH(OH)-CH₂OH、-COOCH₂-CH₂-CH₂OH or-COOCH₂-CH(OH)-CH₃. Preferably R₁Represents a-COOH group.

Preferably, R₂Represents a saturated or unsaturated linear hydrocarbon group preferably having 2 to carbon atoms. In particular, R₂May be pentyl, pentenyl, hexyl or heptyl.

According to one embodiment, the compound of formula (I) is selected from 3-hydroxy-2- [ (2Z) -2-pentenyl ] cyclopentaneacetic acid or 3-hydroxy-2-pentylcyclopentaneacetic acid, and preferably is 3-hydroxy-2-pentylcyclopentaneacetic acid.

The salts of the compounds which can be used according to the invention are chosen in particular from alkali metal salts, such as sodium or potassium salts; alkaline earth metal salts, such as calcium, magnesium or strontium salts; metal salts such as zinc, aluminum, manganese or copper salts; formula NH₄ ⁺The ammonium salt of (1); a quaternary ammonium salt; organic amine salts such as methylamine salt, dimethylamine salt, trimethylamine salt, triethylamine salt, ethylamine salt, 2-hydroxyethylamine salt, bis (2-hydroxyethyl) amine salt or tris (2-hydroxyethyl) amine salt; or a lysine salt or an arginine salt. Preferably, a salt selected from the following is used: sodium, potassium, calcium, magnesium, strontium, copper, manganese or zinc salts.

The following compounds are preferably used as jasmonic acid derivatives (Mexoryl SBO).

Preferably, the jasmonic acid derivative has a logP of-0.7 to 6, preferably-0.6 to 5, more preferably-0.5 to 4.

Preferably, the hydrotrope is present in an amount ranging from 0.1 wt.% to 10 wt.%, preferably from 0.5 wt.% to 8 wt.%, more preferably from 1 wt.% to 5 wt.%, relative to the total weight of the composition.

AMPS polymers

The AMPS polymers used according to the invention are crosslinked or non-crosslinked homo-or copolymers comprising at least acrylamido-2-methylpropanesulfonic acid monomer in a form partially or totally neutralized with an inorganic base different from ammonia (for example sodium hydroxide or potassium hydroxide).

They are preferably fully neutralized or virtually fully neutralized (i.e., at least 90% neutralized).

These AMPS polymers according to the invention may be crosslinked or uncrosslinked.

When the polymer is crosslinked, the crosslinking agent may be selected from the group of polyethylenically unsaturated compounds which are commonly used for crosslinking of polymers obtained by free-radical polymerization.

Examples of crosslinking agents which may be mentioned include divinylbenzene, diallyl ether, dipropylene glycol diallyl ether, polyethylene glycol diallyl ether, triethylene glycol divinyl ether, hydroquinone diallyl ether, ethylene glycol or tetraethylene glycol di (meth) acrylate, trimethylolpropane triacrylate, methylenebisacrylamide, methylenebismethacrylamide, triallylamine, triallyl cyanurate, diallyl maleate, tetraallylethylenediamine, tetraallyloxyethane, trimethylolpropane diallyl ether, allyl (meth) acrylate, allyl ethers of alcohols of the sugar series (allylic ether), or other allyl ethers or vinyl ethers of polyfunctional alcohols, and also allyl esters of phosphoric acid and/or vinylphosphonic acid derivatives, or mixtures of these compounds.

According to one embodiment of the invention, the crosslinking agent is selected from the group consisting of methylenebisacrylamide, allyl methacrylate, and trimethylolpropane triacrylate (TMPTA). The degree of crosslinking is generally in the range from 0.01 to 10 mol% and more particularly from 0.2 to 2 mol% relative to the polymer.

The AMPS polymers according to the invention are water-soluble or water-dispersible. In this case, they are:

"homopolymers" comprising only AMPS monomers and, if they are crosslinked, one or more crosslinking agents (such as those defined above);

or copolymers obtained from AMPS and from one or more hydrophilic or hydrophobic ethylenically unsaturated monomers and, if they are crosslinked, one or more crosslinking agents (such as those defined above). When the copolymer comprises hydrophobic ethylenically unsaturated monomers, these monomers do not comprise a fatty chain and are preferably present in small amounts.

For the purposes of the present invention, the term "aliphatic chain" denotes any hydrocarbon-based chain containing at least 7 carbon atoms.

The term "water-soluble or water-dispersible" denotes polymers: when introduced into the aqueous phase to a mass concentration equal to 1% at 25 ℃, it makes it possible to obtain a macroscopically homogeneous and transparent solution, i.e. a solution having a maximum light transmission value of at least 60% and preferably at least 70% at a wavelength equal to 500nm through a 1cm thick sample.

The "homopolymers" according to the invention are preferably crosslinked and neutralized and they can be obtained according to a preparation process comprising the following steps:

(a) dispersing or dissolving the monomer (such as AMPS) in free form in a solution of tert-butanol or a solution of water and tert-butanol;

(b) one or more inorganic or organic bases (preferably ammonia NH) in an amount making it possible to obtain a degree of neutralization of the sulfonic acid functions of the polymer ranging from 90% to 100%₃) Neutralizing the solution or dispersion of the monomer obtained in (a);

(c) adding a crosslinking monomer to the solution or dispersion obtained in (b);

(d) performing standard free radical polymerization in the presence of a free radical initiator at a temperature in the range of 10 to 150 ℃; the polymer is precipitated in a solution or dispersion based on tert-butanol.

The AMPS homopolymer according to the invention is preferably an optionally crosslinked and/or neutralized 2-acrylamido-2-methylpropanesulfonic acid homopolymer, for example under the name Hostacerin, from Clariant

Poly (2-acrylamido-2-methylpropanesulfonic acid) sold (CTFA name: ammonium polyacryloyldimethyltauamide).

The water-soluble or water-dispersible AMPS copolymer according to the present invention contains a water-soluble ethylenically unsaturated monomer, a hydrophobic monomer, or a mixture thereof.

The water-soluble comonomer may be ionic or non-ionic.

Among the ionic water-soluble comonomers, examples which may be mentioned include the following compounds and their salts:

a mixture of (meth) acrylic acid and (meth) acrylic acid,

-a styrene sulfonic acid,

-vinylsulfonic acid and (meth) allylsulfonic acid,

-a vinyl phosphonic acid,

-a maleic acid, the maleic acid being,

-a source of itaconic acid,

-a crotonic acid, which is,

-a water-soluble vinyl monomer of formula (V) below:

wherein:

-R₁selected from H, -CH₃、-C₂H₅and-C₃H₇

-X₁Selected from:

--OR₂alkyl ethers of the type in which R₂Is a linear or branched, saturated or unsaturated radical containing from 1 to 6 carbon atomsIn the hydrocarbon radical, which is substituted by at least one sulfonate group (-SO)₃ ^-) And/or sulfate (-SO)₄ ^-) And/or phosphate (-PO)₄H₂ ^-) And (4) substituting the group.

Among the nonionic water-soluble comonomers, examples which may be mentioned include:

(ii) a (meth) acrylamide,

-N-vinylacetamide and N-methyl-N-vinylacetamide,

-N-vinylformamide and N-methyl-N-vinylformamide,

-a maleic anhydride,

-a vinyl amine, the vinyl amine being a vinyl amine,

n-vinyllactams comprising cycloalkyl groups having from 4 to 9 carbon atoms, such as N-vinylpyrrolidone, N-butyrolactam and N-vinylcaprolactam,

-formula CH₂(ii) vinyl alcohol of CHOH,

-a water-soluble vinyl monomer of formula (VI):

wherein:

-R₁₅selected from H, -CH₃、-C₂H₅and-C₃H₇

-X₂Selected from:

--OR₁₆alkyl ethers of the type in which R₁₆Is a linear or branched, saturated or unsaturated hydrocarbon-based radical containing from 1 to 6 carbons, optionally substituted with halogen atoms (iodine, bromine, chlorine or fluorine), hydroxyl (-OH), ether.

Mention is made, for example, of glycidyl (meth) acrylate; hydroxyethyl methacrylate; and (meth) acrylates of ethylene glycol, diethylene glycol or polyalkylene glycol.

Among the hydrophobic comonomers free of fatty chains, examples which may be mentioned include:

styrene and its derivatives, such as 4-butylstyrene, alpha-methylstyrene and vinyltoluene,

-formula CH₂＝CH-OCOCH₃Vinyl acetate of (a);

-formula CH₂Vinyl ethers of ═ CHOR, where R is a linear or branched, saturated or unsaturated hydrocarbon-based group containing 1 to 6 carbons;

-acrylonitrile, and (b) acrylonitrile,

-a caprolactone ester having a caprolactone-based skeleton,

-vinyl chloride and vinylidene chloride,

silicone derivatives which, after polymerization, give silicone polymers, such as methacryloxypropyltris (trimethylsiloxy) silane and silicone methacrylamide, siloxy

-a hydrophobic vinyl monomer of formula (VII):

wherein:

-R₂₃selected from H, -CH₃、-C₂H₅and-C₃H₇

-X₃Selected from:

--OR₂₄alkyl ethers of the type in which R₂₄Is a straight or branched, saturated or unsaturated hydrocarbon-based radical containing from 1 to 6 carbon atoms.

Mention may be made, for example, of methyl methacrylate, ethyl methacrylate, n-butyl (meth) acrylate, tert-butyl (meth) acrylate, cyclohexyl acrylate and isobornyl acrylate, and 2-ethylhexyl acrylate.

The water-soluble or water-dispersible AMPS polymers of the invention preferably have a molar mass in the range from 50000 to 10000000 g/mol, preferably from 80000 to 8000000 g/mol and even more preferably from 100000 to 7000000 g/mol.

Examples of water-soluble or water-dispersible AMPS homopolymers which may be mentioned according to the invention include crosslinked or uncrosslinked polymers of sodium acrylamido-2-methylpropanesulfonate, for example the commercial product Simulgel^TM800 (CTFA name: sodium polyacryloyldimethyltaurate).

Examples of water-soluble or water-dispersible AMPS copolymers which may be mentioned according to the invention include:

copolymers of AMPS and vinylpyrrolidone or vinylformamide, such as the copolymers used in the commercial product sold under the name Aristoflex AVC by the company Clariant (CTFA name: Acrylyldimethyltauric ammonium/VP copolymer), but neutralized with sodium hydroxide or potassium hydroxide;

copolymers of AMPS and sodium acrylate, e.g. AMPS/sodium acrylate copolymers, for example under the name Simulgel from SEPPIC^TMCopolymers used in commercial products sold by EG (CTFA name: acrylamide/sodium acryloyldimethyl taurate/isohexadecane/polysorbate-80);

copolymers of AMPS and hydroxyethyl acrylate, such as AMPS/hydroxyethyl acrylate copolymers, for example the copolymers used in the commercial products sold under the name EMT 10 by the company SEPPIC (CTFA name: hydroxyethyl acrylate/sodium acryloyldimethyltaurate copolymer).

Preferred polymers are more particularly optionally crosslinked and/or neutralized copolymers of AMPS and hydroxyethyl acrylate.

The AMPS polymer comprises from 0.1 wt.% to 5 wt.%, preferably from 0.5 wt.% to 3 wt.%, more preferably from 0.6 wt.% to 1.5 wt.%, of the total weight of the oil-in-water emulsion polymer.

Nonionic surfactant

In a preferred embodiment, the composition according to the invention comprises at least one nonionic surfactant selected from the group consisting of the oxyalkylenated fatty acid esters of sorbitan.

Surfactants of this type which may be mentioned include more particularly:

oxyethylenated fatty acid esters of sorbitan, such as (INCI name) polysorbate 20, polysorbate 40, polysorbate 60, polysorbate 65, polysorbate 80, polysorbate 85, PEG-5 sorbitan isostearate, PEG-20 sorbitan triisostearate, PEG-20 sorbitan isostearate, PEG-40sorbitan heptaoleate (PEG-40sorbitan heptaoleate), PEG-20 sorbitan tetraoleate and PEG-20 sorbitan trioleate.

Mention may be made of polysorbate 20, for example under the trade name Tween by the company Croda^TMThose sold by 20-LQ- (AP).

If present, the nonionic surfactant is present in an amount effective to ensure stability of the composition according to the invention.

The compositions of the present invention are stable over time in the presence of nonionic surfactants selected from the group consisting of the oxyalkylenated fatty acid esters of sorbitan.

The emulsion is stable if no change in its macroscopic or microscopic appearance and its physicochemical properties (droplet size, pH, viscosity) is observed after storage at various temperatures (T ═ 4 ℃, room temperature, 40 ℃ and 45 ℃) for a duration of 2 months.

Preferably, the nonionic surfactant may be present in an amount ranging from 0.1 wt.% to 3 wt.%, preferably from 0.1 wt.% to 1.5 wt.%, and more preferably from 0.1 wt.% to 1 wt.%, relative to the total weight of the composition.

Aqueous phase

The compositions of the present invention comprise at least one continuous aqueous phase.

The aqueous phase of the composition according to the invention comprises water and optionally one or more water-miscible or at least partially water-miscible compounds, for example C₂To C₈Lower polyols or monohydric alcohols, such as ethanol and isopropanol.

The term "polyol" is understood to mean any organic molecule comprising at least two free hydroxyl groups. Examples of polyols that may be mentioned include diols such as butanediol, propylene glycol and isoprene glycol; caprylyl glycol, glycerin (i.e., glycerol), and polyethylene glycol.

The aqueous phase may also contain any of the common water-soluble or water-dispersible additives as mentioned below.

The aqueous phase may constitute from 30 wt.% to 98 wt.%, preferably from 30 wt.% to 95 wt.%, still more preferably from 50 wt.% to 90 wt.%, and even still more preferably from 60 wt.% to 90 wt.%, relative to the total weight of the composition.

Oil phase

The composition of the invention comprises at least one oily phase dispersed in an aqueous phase as described above.

The nature of the oil phase of the composition according to the invention is not critical.

In particular, the oil phase comprises at least one oil.

The term "oil" refers to any fat body that is in liquid form at room temperature (20-25 ℃) and atmospheric pressure. These oils may be of animal, vegetable, mineral or synthetic origin.

The oil may be volatile or non-volatile.

The term "volatile oil" refers to any non-aqueous medium capable of evaporating from the skin or lips in less than 1 hour at room temperature (20-25 ℃) and atmospheric pressure (760 mmHg). Volatile oils are volatile cosmetic oils that are liquid at room temperature. More specifically, the volatile oil has a viscosity of between 0.01mg/cm²Min and 200mg/cm²Evaporation rate between/min (inclusive).

The term "non-volatile oil" is intended to mean an oil that remains on the keratin materials at ambient temperature and atmospheric pressure. More specifically, the non-volatile oil has a viscosity of strictly 0.01mg/cm²Evaporation rate below/min.

To measure this evaporation rate, 15g of the oil or oil mixture to be tested are introduced into a crystallizer of diameter 7cm placed on a balance at 0.3m with a temperature controlled at 25 ℃ and a humidity controlled at 50% relative humidity³In the large chamber. The liquid was allowed to evaporate freely without stirring by: the ventilation was provided by means of a fan (PAPST-MOTOREN, reference 8550N, rotating at 2700 rpm) located vertically above the crystallizer containing the solvent, with the blades directed towards the crystallizer and at a distance of 20cm from the base of the crystallizer. The mass of oil remaining in the crystallizer is measured at regular intervals. Evaporation rate in units per surface area (cm)²) And oil evaporated per time unit (min)The number of milligrams indicates.

Oils suitable for use in the present invention are not limited and may be hydrocarbon-based, silicone-based, or fluorine-based.

According to the invention, the term "silicone oil" means an oil comprising at least one silicon atom (and in particular at least one Si-O group).

The term "fluoro oil" refers to an oil comprising at least one fluorine atom.

The term "hydrocarbon oil" refers to an oil containing primarily hydrogen and carbon atoms.

The oil may optionally include oxygen, nitrogen, sulfur and/or phosphorus atoms, for example in the form of hydroxyl or acid groups.

The oil phase may be present in an amount ranging from 1 wt.% to 70 wt.%, preferably from 10 wt.% to 70 wt.%, and more preferably from 10 wt.% to 40 wt.%, relative to the total weight of the composition.

As noted above, such amounts of the oil phase do not include the amount of emulsifier.

Additive agent

In a known manner, the composition according to the invention may also contain one or more additives commonly found in cosmetics or dermatology.

Examples of adjuvants that may be mentioned include emulsifiers, gelling agents, active agents, preservatives, antioxidants, fragrances, sunscreens (═ UV screening agents), additional dyes, alkaline agents (triethanolamine, diethanolamine or sodium hydroxide) or acidic agents (citric acid), and also lipid vesicles or any other type of carrier (nanocapsules, microcapsules, etc.), and mixtures thereof.

These additives are used in the proportions usual in the cosmetic field, for example from 0.01% to 30% by weight of the total composition, and depending on their nature, they are incorporated into the aqueous phase or into the oily phase of the composition, or into vesicles or any other type of carrier.

These additives and their concentrations must be such that they do not alter the desired properties of the compositions of the present invention.

According to a preferred embodiment, the present invention relates to a composition for lightening or whitening keratin materials in the form of an emulsion comprising, dispersed in an aqueous phase, an oily phase and comprising, relative to the total weight of the composition:

(i) as skin lightening or whitening active ingredients:

0.1 to 0.5 wt.% of at least one flavone; and

0.1 to 0.5 wt.% of at least one hydroxylated diphenylmethane derivative selected from those of the following formula (I):

wherein:

-R₁、R₂、R₄and R₅Represents a hydrogen atom;

-R₃is methyl;

-the OH groups are in ortho and para position with respect to the bond formed with the carbon linking the two aromatic nuclei to each other;

(ii)1 to 5 wt.% of at least one hydrotrope selected from the group consisting of: oxothiazolidinecarboxylic acid; vitamin B3 and derivatives thereof, preferably niacinamide; xanthine bases, preferably caffeine; camphorbenzazapine methylsulfate, ellagic acid, hydroxyphenoxypropionic acid, diethyl 2, 4-pyridinedicarboxylate, terephthalylidene dicamphor sulfonic acid, ferulic acid, salicylic acid, phloretin, acetyltrifluoromethylphenylvalylglycine, resveratrol, 4-butylresorcinol, apigenin, phenethylresorcinol, prasterone, benzophenone-3, butylmethoxydibenzoylmethane, octanoylsalicylic acid, ethylhexyl salicylate; and jasmonic acid derivatives, preferably sodium tetrahydrojasmonate;

(iii)0.6 to 1.5 wt.% of at least one optionally crosslinked and/or neutralized 2-acrylamido-2-methylpropanesulfonic acid copolymer; and

(iv)0.1 to 1 wt.% of at least one nonionic surfactant selected from: polysorbate 20, polysorbate 40, polysorbate 60, polysorbate 65, polysorbate 80, polysorbate 85, PEG-5 sorbitan isostearate, PEG-20 sorbitan triisostearate, PEG-20 sorbitan isostearate, PEG-40sorbitan heptaoleate, PEG-20 sorbitan tetraoleate and PEG-20 sorbitan trioleate.

Preferably, the compositions of the invention are in the form of oil-in-water emulsions, for example in the form of emulsions (lotions), creams, gels or liquid foundations, and they are prepared according to conventional methods in the cosmetic field.

The compositions of the invention have a viscosity of less than 50UD (units of deviation), preferably from 17UD to 35UD, measured at 25 ℃ using a Rheomat 180 viscometer equipped with a spindle M2 rotating at 200 rpm.

The viscosity was measured at 25 ℃ using a ProRheo R180 viscometer from ProRheo Inc. equipped with spindle M2 rotating at 200rpm, as described above.

Method and use

The compositions according to the invention are intended for topical application and may in particular constitute compositions intended for lightening or whitening keratin materials, and in particular human skin.

Thus, in a further aspect, the present invention relates to a cosmetic process for lightening or whitening keratin materials, in particular the skin, comprising the step of applying to the keratin materials a composition as defined above.

The invention is illustrated in more detail by the examples described below, which are given as non-limiting illustrations.

The percentages are by weight of the active ingredient or substance.

In the following examples, the weight percentages are indicated with respect to the total weight of the composition.

Examples

Example 1: preparation of compositions according to inventive and comparative formulations

Compositions according to inventive (inv.)1-2 and comparative (comp.) formulations listed in the following table were prepared:

note: the amount of Scutellariae radix (Scutellaria BAICALENSIS) root extract is calculated by the weight of baicalin.

The preparation method comprises the following steps:

1. preparing an aqueous phase: adding hydrotrope component (nicotinamide and/or caffeine) into water, stirring until completely dissolved, adding radix Scutellariae (Scutellaria BAICALENSIS) root extract, stirring until completely dissolved, and maintaining the temperature at 75 deg.C.

2. Preparing an oil phase: the phenethyl resorcinol and oil were mixed together, heated to 75 ℃ to completely dissolve the phenethyl resorcinol, followed by optional addition of polysorbate 20.

3. The oil phase was added to the aqueous phase and homogenized by a VMI type homogenizer at 1000rpm for 10 minutes.

4. Cooled to below 60 ℃, optionally hydroxyethyl acrylate/sodium acryloyldimethyl taurate copolymer is added and stirred until well dispersed, and then sodium hydroxide is added to adjust the pH to 5.0.

Example 2: evaluation of inventive and comparative formulations

The stability, viscosity and cosmetic properties of the composition according to the inventive formulation prepared in example 1 and the composition according to the comparative formulation were measured.

Stability tests of compositions according to the inventive formulation and compositions according to the comparative formulation at room temperature (25 ℃), 40 ℃, 45 ℃ for two months were carried out using a Binder oven (USA) by leaving the inventive and comparative formulations in the oven for 2 months.

Stability tests of stability at 4 ℃ for two months were performed using a chinese mei-ling refrigerator (YC-260L, china) by leaving the cosmetic composition according to the inventive formulation and the cosmetic composition according to the comparative formulation in the refrigerator for 2 months.

Photostability testing was performed using ATLAC (AMETEK Measurement and Calibration technologies) for 24 hours.

Finally, freeze thaw stability tests were performed using a Binder oven (USA) for 10 cycles. In each cycle, the temperature will gradually change from 20 ℃ to-20 ℃ over a 24 hour period.

The viscosity was measured at 25 ℃ using a ProRheo R180 viscometer from ProRheo Inc. equipped with spindle M2 rotating at 200 rpm.

The results of the stability and viscosity of the compositions according to the inventive formulation and the compositions according to the comparative formulation are listed below.

It can be seen that the viscosity of the composition according to the comparative formulation is too low, which is undesirable.

It can also be seen that the composition according to inventive formulation 1 has good stability at various temperatures.

The lightening or whitening effect of the composition according to inventive formula 1 was carried out using an in vitro protocol as follows:

-porcine skin (external ear) on Franz cell;

5mg/cm of each composition²(application area: 1.77cm²)；

-16 hours at 32 ℃ (time of administration in real life);

-washing after the duration of application;

1-2 applications per well (10 wells per treatment);

-receptor fluid (PBS);

by using

The disk performs stripping;

LC-MS/MS quantification in washes (liquid), Stratum Corneum (SC), skin (epidermis + dermis) and Recipient (RF).

The bioavailability results are listed in the table below.

Consumer panel testing (n 60) showed that the compositions according to inventive formulas 1 and 2 provided better moisturization, nutrition, softness, and dullness resistance to the skin than the compositions according to the comparative formula.

Claims (13)

1. A composition for lightening or whitening keratin materials in the form of an emulsion comprising an oily phase dispersed in an aqueous phase and comprising:

(i) at least one skin lightening or whitening active ingredient selected from flavonoids;

(ii) at least one hydrotrope; and

(iii) at least one polymer derived from 2-acrylamidomethylpropanesulfonic acid.

2. The composition of claim 1, further comprising at least one nonionic surfactant selected from the group consisting of oxyalkylenated fatty acid esters of sorbitan.

3. The composition of claim 2, wherein the non-ionic surfactant is selected from the group consisting of polysorbate 20, polysorbate 40, polysorbate 60, polysorbate 65, polysorbate 80, polysorbate 85, PEG-5 sorbitan isostearate, PEG-20 sorbitan triisostearate, PEG-20 sorbitan isostearate, PEG-40sorbitan heptaoleate, PEG-20 sorbitan tetraoleate, and PEG-20 sorbitan trioleate.

4. The composition of claim 2 or 3, wherein the non-ionic surfactant is present in an amount ranging from 0.1 wt.% to 3 wt.%, preferably from 0.1 wt.% to 1.5 wt.%, and more preferably from 0.1 wt.% to 1 wt.%, relative to the total weight of the composition.

5. The composition according to any one of claims 1 to 4, wherein the flavonoid is selected from, for example, chalcones, flavones, flavanones, flavanols, flavonols, dihydroflavonols, isoflavonoids, neoflavonoids, catechins, anthocyanidins, and tannins.

6. Composition according to any one of claims 1 to 5, wherein the flavonoid is present in an amount ranging from 0.1 to 2 wt.%, preferably from 0.1 to 1 wt.%, more preferably from 0.1 to 0.5 wt.%, relative to the total weight of the composition.

7. The composition according to any one of claims 1 to 6, wherein the hydrotrope is selected from the group consisting of oxothiazolidinecarboxylic acid; vitamin B3 and derivatives thereof, preferably niacinamide; xanthine bases, preferably caffeine; camphorbenzammonium methylsulfate, ellagic acid, hydroxyphenoxypropionic acid, diethyl 2, 4-pyridinedicarboxylate, terephthalylidene dicamphor sulfonic acid, ferulic acid, salicylic acid, phloretin, acetyltrifluoromethylphenylvalylglycine, resveratrol, apigenin, prasterone, benzophenone-3, butylmethoxydibenzoylmethane, octanoylsalicylic acid, ethylhexyl salicylate; and jasmonic acid derivatives, preferably sodium tetrahydrojasmonate.

8. The composition according to any one of claims 1 to 7, wherein the hydrotrope is present in an amount ranging from 0.1 wt.% to 10 wt.%, preferably from 0.5 wt.% to 8 wt.%, more preferably from 1 wt.% to 5 wt.%, relative to the total weight of the composition.

9. The composition according to any one of claims 1 to 8, wherein the polymer derived from 2-acrylamidomethylpropanesulfonic acid is selected from:

i) optionally crosslinked and/or neutralized homopolymer of 2-acrylamido-2-methylpropanesulfonic acid,

ii) optionally crosslinked and/or neutralized 2-acrylamido-2-methylpropanesulfonic acid copolymers, and

iii) mixtures thereof.

10. The composition according to any one of claims 1 to 9, wherein the polymer derived from 2-acrylamidomethylpropanesulfonic acid is present in an amount ranging from 0.1 to 5 wt.%, preferably from 0.5 to 3 wt.%, more preferably from 0.6 to 1.5 wt.%, relative to the total weight of the composition.

11. The composition according to any one of claims 1 to 10, further comprising as a skin whitening ingredient a hydroxylated diphenylmethane derivative selected from those of the following formula (I):

wherein:

R₁selected from the group consisting of a hydrogen atom, a methyl group, a saturated or unsaturated, linear or branched hydrocarbon chain containing from 2 to 4 carbon atoms, -an OH group and a halogen,

R₂selected from the group consisting of a hydrogen atom, a methyl group, and a saturated or unsaturated, linear or branched hydrocarbon chain containing 2 to 5 carbon atoms,

R₃selected from methyl or a saturated or unsaturated, linear or branched hydrocarbon chain containing from 2 to 5 carbon atoms,

R₄and R₅Independently of one another, from a hydrogen atom, a methyl group, a saturated or unsaturated, linear or branched hydrocarbon chain containing from 2 to 5 carbon atoms, -an OH group or a halogen.

12. A composition for lightening or whitening keratin materials, in the form of an emulsion comprising an oily phase dispersed in an aqueous phase and comprising, relative to the total weight of the composition:

(i) as skin lightening or whitening active ingredients:

0.1 to 0.5 wt.% of at least one flavone; and

0.1 to 0.5 wt.% of at least one hydroxylated diphenylmethane derivative selected from those of the following formula (4):

wherein:

-R₁、R₂、R₄and R₅Represents a hydrogen atom;

-R₃is methyl;

-the OH groups are in ortho and para position with respect to the bond formed with the carbon linking the two aromatic nuclei to each other;

(ii)1 to 5 wt.% of at least one hydrotrope selected from the group consisting of: oxothiazolidinecarboxylic acid; vitamin B3 and derivatives thereof, preferably niacinamide; xanthine bases, preferably caffeine; camphorbenzazapine methylsulfate, ellagic acid, hydroxyphenoxypropionic acid, diethyl 2, 4-pyridinedicarboxylate, terephthalylidene dicamphor sulfonic acid, ferulic acid, salicylic acid, phloretin, acetyltrifluoromethylphenylvalylglycine, resveratrol, 4-butylresorcinol, apigenin, phenethylresorcinol, prasterone, benzophenone-3, butylmethoxydibenzoylmethane, octanoylsalicylic acid, ethylhexyl salicylate; and jasmonic acid derivatives, preferably sodium tetrahydrojasmonate;

(iii)0.6 to 1.5 wt.% of at least one optionally crosslinked and/or neutralized 2-acrylamido-2-methylpropanesulfonic acid copolymer; and

(iv)0.1 to 1 wt.% of at least one nonionic surfactant selected from: polysorbate 20, polysorbate 40, polysorbate 60, polysorbate 65, polysorbate 80, polysorbate 85, PEG-5 sorbitan isostearate, PEG-20 sorbitan triisostearate, PEG-20 sorbitan isostearate, PEG-40sorbitan heptaoleate, PEG-20 sorbitan tetraoleate and PEG-20 sorbitan trioleate.

13. Cosmetic process for lightening or whitening a keratin material, in particular the human skin, comprising a step of applying on the keratin material a composition according to any one of claims 1 to 12.