COMPOSITION COMPRISING AT LEAST TWO FATTY ACID ESTERS OF (POLY)GLYCEROL, AND USE THEREOF IN COSMETICS

Abstract

The invention relates to a composition in the form of a nanoemulsion or microemulsion, comprising: at least two different fatty acid esters of (poly)glycerol a) and b); c) at least one polyol in a total content of greater than 15% by weight; d) at least one oil; e) water; and f) at least one anionic surfactant of formula (II)

##STR00001##

it being understood that said composition comprises at least one anionic surfactant of formula (II) when the first fatty acid ester of (poly)glycerol is a polyglyceryl laurate comprising from 3 to 6 glycerol units and the second fatty acid ester of (poly)glycerol is a (poly)glyceryl laurate comprising from 1 to 3 glycerol units.

The invention also relates to a cosmetic treatment process for reducing and/or preventing the signs of ageing of keratin materials such as the skin, by application of such a composition.

Claims

1. A cosmetic process for at least one of promoting keratinocyte renewal, preventing and/or reducing the signs of skin ageing, wherein the process comprises applying to the skin of an individual wishing to at least one of promoting keratinocyte renewal, preventing and/or reducing the signs of aging a composition in the form of a nanoemulsion or microemulsion, comprising: a) a first fatty acid ester of polyglycerol which is chosen from a fatty acid ester of polyglycerol formed from at least one acid comprising an alkyl or alkenyl chain containing from 12 to 20 carbon atoms and from 3 to 6 glycerol units; b) a second fatty acid ester of (poly)glycerol which is chosen from a fatty acid ester of (poly)glycerol formed from at least one acid comprising an alkyl or alkenyl chain containing from 6 to 18 carbon atoms and from 1 to 3 glycerol units; c) at least one polyol in a total content ranging from 20% to 40% by weight relative to the total weight of the composition; d) at least one oil; e) water; and f) at least one anionic surfactant of formula (II) present in a total content of from 0.05% 1% by weight ##STR00005## in which: R.sub.1 is a, saturated or unsaturated, linear or branched alkyl chain containing from 7 to 17 carbon atoms, R.sub.2 is H or a methyl, R.sub.3 is H, COO.sup.−M.sup.+, CH.sub.2COO.sup.−M.sup.+ or COOH, n is from 0 to 2, X is COO.sup.− or SO.sub.3.sup.− and M represents independently H, sodium, potassium or sorbitan, and wherein the [total amount of fatty acid ester(s) of polyglycerol (a)] to [total amount of fatty acid ester(s) of (poly)glycerol (b)] weight ratio ranges from 1 to 2.

2. The cosmetic process according to claim 2, for reducing and/or preventing the signs of ageing of the skin which comprises applying the composition to mature and/or wrinkled skin.

3. The cosmetic process according to claim 1, the signs of skin ageing are chosen from at least one of thinning of the epidermis, surface wrinkles, impairments of the barrier function, the properties of stretchability, tonicity, firmness, suppleness and/or elasticity of the skin.

4. The cosmetic process according to claim 1, which comprises stimulating keratinocyte proliferation and of the synthesis of the structural molecules of the skin.

5. The cosmetic process according to claim 4, wherein, the structural molecules of the skin comprise filaggrin.

6. The cosmetic process according to claim 1, wherein the individual is at least 30 years old.

7. The cosmetic process according to claim 1, wherein the individual is at least 40 years old.

8. The cosmetic process according to claim 1, wherein the individual is at least 50 years old.

9. The cosmetic process according to claim 1, wherein the first fatty acid ester of polyglycerol a) is chosen from polyglyceryl monolaurate comprising from 4 to 6 glycerol units, polyglyceryl monooleate comprising from 4 to 6 glycerol units, polyglyceryl mono(iso)stearate comprising from 4 to 6 glycerol units, polyglyceryl monolaurate comprising from 4 to 6 glycerol units, polyglyceryl dioleate comprising from 4 to 6 glycerol units, polyglyceryl monomyristate comprising from 4 to 6 glycerol units, and mixtures thereof.

10. The cosmetic process according to claim 1, wherein the second fatty acid ester of (poly)glycerol b) is chosen from (poly)glyceryl monolaurate comprising from 1 to 3 glycerol units, (poly)glyceryl monocaprate comprising from 1 to 3 glycerol units, (poly)glyceryl monocaprylate comprising from 1 to 3 glycerol units, (poly)glyceryl monostearate comprising from 1 to 3 glycerol units, and mixtures thereof.

11. The cosmetic process according to claim 1, wherein the first fatty acid ester of polyglycerol a) has an HLB value of 10 to 13, and/or in that the second fatty acid ester of (poly)glycerol b) has an HLB value of 8 to 10.

12. The cosmetic process according to claim 1, wherein the first fatty acid ester of polyglycerol a) is a polyglyceryl monolaurate comprising 4 to 6 glycerol units and the second fatty acid ester of (poly)glycerol b) is chosen from (poly)glyceryl monolaurate comprising from 1 to 3 glycerol units and (poly)glyceryl monocaprate comprising from 1 to 3 glycerol units.

13. The cosmetic process according to claim 1, which comprises at least one anionic surfactant of formula (III): ##STR00006## in which: R.sub.1 is a saturated or unsaturated, linear or branched alkyl chain with from 7 to 17 carbon atoms, R.sub.2 is H or methyl, and M is H, sodium or potassium.

14. The cosmetic process according to claim 1, wherein said polyol (c) is chosen from glycerol, diglycerol, polyglycerol, propylene glycol, butylene glycol, pentylene glycol, hexylene glycol, dipropylene glycol, diethylene glycol, 1,3-propanediol, 1,5-pentanediol, polyethylene glycols, and sugars and a mixture thereof.

15. The cosmetic process according to claim 1, wherein said oil(s) (d) is (are) chosen from the group constituted of oils of plant origin, mineral oils, synthetic oils, silicone oils and hydrocarbon-based oils.

16. The cosmetic process according to claim 1, which is in the form of an oil-in-water (O/W) emulsion, and the oil (d) is in the form of droplets with a number-average particle size of 300 nm or less.

17. The cosmetic process according to claim 1, wherein the oil(s) (d) is (are) present in a content of from 1% to 15% by weight, the amount of fatty acid ester(s) of polyglycerol (a) is 2% to 9% by weight, the amount of fatty acid ester(s) of (poly)glycerol (b) is 1.5% to 7% by weight, the total amount of fatty acid ester(s) of polyglycerol (a) and the total amount of fatty acid ester(s) of (poly)glycerol (b) is 3.5% to 16% relative to the total weight of the composition.

Description

EXAMPLE 1: COSMETIC COMPOSITION ACCORDING TO THE INVENTION

[0196] A facial care lotion having the following composition was prepared:

TABLE-US-00001 % by weight relative to the total weight of Phases Ingredients the composition A Polyglyceryl-2 laurate or PG-2 laurate 2 (Sunsoft Q-12D-C ® from Taiyo Kagaku) Polyglyceryl-5 laurate or PG-5 laurate 3 (Sunsoft A-121E ® from Taiyo Kagaku) 2-Ethylhexyl palmitate (2-Ethylhexyl 5 palmitate (Cegesoft C24 ® from BASF) Sodium N-methylstearoyltaurate or sodium 0.1 methyl stearoyl taurate (Nikkol SMT ® from Nikko) B water qs 100 C Butylene glycol 20 (1,2-Propylene glycol Care ® from BASF) D Phenoxyethanol 0.5 1,2-Octanediol (Minacare Octiol ® from 0.5 Minasolve)

Preparation Method:

[0197] (1) ethylhexyl palmitate, sodium N-methylstearoyltaurate, polyglyceryl-5 laurate and polyglyceryl-2 laurate were mixed to form an oily phase A;

[0198] (2) the oily phase A was heated to about 70° C.;

[0199] (3) water B was added to the oily phase A with stirring to obtain an oil-in-water microemulsion;

[0200] (4) the polyol (butyleneglycol) was mixed, and then solution C was added to the microemulsion;

[0201] (5) phase D (phenoxyethanol and 1,2-octanediol) was added.

[0202] The composition is single-phase and clear, and remains stable and homogeneous after storage for 3 months at 4° C.

[0203] This composition may be applied regularly to facial skin in order to attenuate the signs of skin ageing.

EXAMPLE 2: COSMETIC COMPOSITION ACCORDING TO THE INVENTION

[0204] A facial care lotion having the following composition was prepared:

TABLE-US-00002 % by weight relative to the total weight of Phases Ingredients the composition A Polyglyceryl-2 caprate or PG-2 caprate 6 (Sunsoft Q-10D-C ® from Taiyo Kagaku) Polyglyceryl-5 laurate or PG-5 laurate 8 (Sunsoft A-121E ® from Taiyo Kagaku) Isopropyl myristate (Isopropylmyristate ® 4 from BASF) B water qs 100 C Dipropylene glycol 25 (Dipropylene glycol LO+ ® from Dow Chemical) D 1,2-Octanediol (Minacare Octiol ® from 0.5 Minasolve) Phenoxyethanol 0.5 ethanol 10

Preparation Method

[0205] (1) isopropyl myristate, polyglyceryl-5 laurate and polyglyceryl-2 caprate were mixed to form an oily phase A;

[0206] (2) the oily phase A was heated to about 70° C.;

[0207] (3) water B was added to the oily phase A with stirring to obtain an oil-in-water microemulsion;

[0208] (4) the polyol (dipropylene glycol) was mixed, and then solution C was added to the microemulsion;

[0209] (5) phase D (phenoxyethanol, ethanol and 1,2-octanediol) was added.

[0210] The composition is single-phase and clear, and remains stable and homogeneous after storage for 3 months at 40° C.

[0211] This composition may be applied regularly to facial skin in order to attenuate the signs of skin ageing and in particular to prevent or treat thinned skin.

EXAMPLE 3: EVALUATION OF THE BENEFICIAL EFFECTS OF A COMPOSITION ACCORDING TO THE INVENTION ON THE SIGNS OF SKIN AGEING, BY EVALUATING FILAGGRIN EXPRESSION AND THE THICKNESS OF THE EPIDERMIS

[0212] The beneficial effects of a composition according to the invention on the signs of skin ageing on a mature skin were evaluated using the model of Voorhees et al. (British Journal of dermatology, 1993, 129, 389-392).

Material and Method: 29 subjects (10 men/19 women) exhibiting photo-aged skin on the forearms (score >5 on the McKenzie scale) were treated with topical application by patch of various compositions for 12 hours, with: [0213] composition 2 according to the invention in the form of a microemulsion (composition of Example 2) [0214] comparative example 3, outside the invention, which is a composition in conventional emulsion form comprising 0.1% of retinol by weight [0215] comparative example 4, outside the invention, which is a composition identical to that of comparative example 3, conventional emulsion, but without the retinol active agent [0216] an empty patch without composition.

[0217] Applications of 30 microlitres of formulas were carried out under patches for 12 consecutive days, the patches having been renewed every 4 days. Upon final removal of the patches (day 13), skin biopsies 2 mm in diameter were carried out on the application sites.

[0218] The skin samples were fixed in a phosphate buffer containing 10% formaldehyde, embedded in paraffin and treated for histological analysis. Part of the sections were cut at 5 micrometres, mounted on slides and stained with haematoxylineosin, according to standard procedures.

[0219] The slides are photographed digitally, and the thickness of the epidermis is automatically measured by dedicated software at 15 measurements per field, each slide having two fields.

[0220] The other paraffin sections that were mounted on slides are deparaffinized in xylene, rehydrated and prepared for immunolabelling by immunoperoxidase according to standard procedures.

[0221] After incubation with anti-filaggrin primary antibodies, the slides were washed and incubated with the biotinylated secondary antibody. The slides were then washed and treated with avidin-biotin-peroxidase for 30 minutes at ambient temperature. The slides were then revealed with 0.05% 3,39-diaminobenzidine and 0.03% H.sub.2O.sub.2.

[0222] The slides are photographed digitally, and the thickness of the epidermis labelled with the antibody is automatically measured by dedicated software at 15 measurements per field, each slide having two fields.

[0223] The results hereinafter are expressed by calculating the mean and the standard deviation on all of the measurements carried out. The statistical comparisons between treatments were carried out using repeated-measurement mixed models (ANOVA). A comparison is considered to be significant for a p<0.05.

[0224] The compositions of comparative examples 3 and 4 are compositions in emulsion form, but are not microemulsions or nanoemulsions as defined according to the invention, comprising respectively 0.1% of retinol which is a well-known antiaging active agent, or 0% of retinol.

[0225] The numerical values for the amounts of the components described in the table hereinafter are all based on weight percentages of starting materials relative to the total weight of the composition.

TABLE-US-00003 Comparative example 3 (outside the Comparative invention) example 4 comprising 0.1% (outside the Ingredients of retinol invention) D Sodium hydroxide 0.2 0.2 B Preserving agent 1 1 A CAPRYLIC/CAPRIC 8 8 TRIGLYCERIDE (ERIDES C8C10 70/30 (DUB MCT 7030) ® from STEARINERIE DUBOIS) A APRICOT KERNEL OIL 6 6 (APRICOT KERNEL OIL REFINED ® from GUSTAV HEESS) A CETYL ALCOHOL 0.5 0.5 (LANETTE 16 ® from BASF) A MYRISTYL MYRISTATE 2 2 (TEGOSOFT MM ® from EVONIK GOLDSCHMIDT) D ACRYLATES/C10-30 0.5 0.5 ALKYL ACRYLATE CROSSPOLYMER (CARBOPOL ULTREZ 20 ® POLYMER from LUBRIZOL) B WATER qs qs A STEARIC ACID 1.5 1.5 (STEARIC ACID 1850 ® from SOUTHERN ACIDS) A SODIUM STEAROYL 1 1 GLUTAMATE (AMISOFT HS 11 PF ® from AJINOMOTO) E RETINOL (RETINOL 0.1 10 S ® from the company BASF)

Preparation Method:

[0226] The preparation must be carried out in an oxygen-free atmosphere (under nitrogen) in order to avoid degradation of the retinol. Heat phase A and phase B at 80° C. Prepare the pre-gel of phase D by dusting the polymer onto the water while stirring using a deflocculator (Rayneri) and neutralize with sodium hydroxide. While stirring using a deflocculator (Rayneri), add phase D to phase B when the gel is uniform (temperature 38° C.), add phase A while stirring using a deflocculator (Rayneri) to phase B+D at a speed of 1000 rpm for 3 min, then at a temperature <30° C., add the retinol (E).

[0227] These formulas of comparative examples 3 and 4 are stable for three months at ambient temperature or stored at 40° C.

Results:

Histological Evaluation of Filaggrin Expression

[0228]

TABLE-US-00004 Filaggrin expression (labelled epidermal thickness, μm) Application of Mean Standard deviation Composition 2 according 27.53 17.93 to the invention Comparative example 3 25.50 9.84 (outside the invention) comprising 0.1% of retinol Comparative example 4 16.16 10.99 (outside the invention) not comprising retinol empty patch without 12.24 7.77 composition

[0229] The parameter measured is filaggrin expression by measuring the thickness of epidermis labelled with the antibody.

[0230] It was noted that the filaggrin expression is significantly higher for the skins on which the patch with composition 2 according to the invention of microemulsion type was applied, compared with an application with a patch comprising a composition outside the invention (comparative example 4) of conventional emulsion type not comprising retinol (that is to say not comprising anti-ageing active agents), and also compared with the application with a patch not comprising composition (p<0.05).

[0231] It was also noted, unexpectedly, that the filaggrin expression for the skins on which the patch with composition 2 according to the invention of microemulsion type was applied is not significantly different compared with an application with a patch comprising a composition outside the invention (comparative example 3) comprising 0.1% of retinol (which is a known anti-ageing active agent) (p=0.8), that is to say composition 2 according to the invention in microemulsion form allows filaggrin expression that is as good as a composition of conventional emulsion type comprising an anti-ageing active agent (retinol).

Histological Evaluation of the Thickness of the Epidermis

[0232]

TABLE-US-00005 Epidermal thickness (μm) Application of: Mean Standard deviation Composition 2 according 79.36 21.91 to the invention Comparative example 3 84.00 24.76 (outside the invention) comprising 0.1% of retinol Comparative example 4 66.86 32.13 (outside the invention) not comprising retinol empty patch without 66.00 23.79 composition

[0233] The parameter measured is the epidermal thickness.

[0234] It was noted that the thickness of the epidermis is significantly higher after the application of the patch with composition 2 according to the invention of microemulsion type, compared with the application with a patch not comprising composition (p<0.05).

[0235] It was also noted, unexpectedly, that the thickness of the epidermis for the skins on which the patch with composition 2 according to the invention of microemulsion type was applied is not significantly different compared with an application with a patch comprising a composition outside the invention (comparative example 3) comprising 0.1% of retinol (which is a known anti-ageing active agent) (p=0.25), that is to say composition 2 according to the invention in microemulsion form makes it possible to obtain an epidermal thickness similar to a composition of conventional emulsion type comprising an anti-ageing active agent (retinol).

[0236] Thus, unexpectedly, a composition according to the invention, in microemulsion or nanoemulsion form, and which does not comprise anti-ageing active agents such as retinol, is significantly as effective as a composition of conventional emulsion type comprising 0.1% of retinol, for preventing or reducing the decrease in the thickness of the epidermis, and thus as effective for preventing and treating the signs of skin ageing.

EXAMPLE 4: EVALUATION OF THE BENEFICIAL EFFECTS OF A COMPOSITION ACCORDING TO THE INVENTION ON THE SIGNS OF SKIN AGEING SUCH AS WRINKLES AND FIRMNESS OR TONICITY OF THE SKIN

[0237] The beneficial effects of a composition according to the invention on the signs of skin ageing on mature or very mature skin were evaluated by clinical evaluation and instrumental measurements.

Material and Method:

[0238] 80 women aged 40 to 65, exhibiting clinical signs of age, were treated every day with the products under investigation, on the face for 6 months, with: [0239] composition 1 according to the invention in the form of a microemulsion (composition of Example 1).

[0240] The 80 subjects return to the investigation centre after 7, 14, 28, 56, 84 and 168 days of treatment in order for clinical and instrumental evaluations to be carried out.

[0241] One of the signs of skin ageing evaluated is in particular the crows feet wrinkles, which are wrinkles located at the outer corners of the eyes.

Results

[0242] At each evaluation visit, a trained expert scores the severity of the wrinkles of the subjects having been treated with composition 1, according to a photographic scale graded from 1 to 6.

[0243] The results are expressed by calculating the mean of the scores of all the subjects evaluated. The statistical comparisons between treatments were carried out using repeated-measurement mixed models (ANOVA). A comparison is considered to be significant for a p<0.05.

Crows Feet Wrinkles: Variation of the Clinical Score Compared with the First Day of Study

TABLE-US-00006 Days mean p. value Day 07 −0.040 0.713 Day 14 −0.355 0.001 Day 28 −0.355 0.001 Day 56 −0.461 0.000 Day 84 −0.592 0.000 Day 168 −0.671 0.000

[0244] It was noted that when composition 1 according to the invention is applied to the facial skin, the improvement in the score of the crows feet wrinkles is significant compared to the initial state, as early as 14 days of treatment (p<0.001), this being up to the end of the treatment at 6 months.

[0245] Composition 1 according to the invention applied to the skin makes it possible to reduce the skin wrinkles, and in particular the crows feet wrinkles of the facial skin.

[0246] Instrumental measurements of facial skin tonicity were also carried out using an apparatus dedicated to viscoelastic measurement of the skin, the cutometer (Courage and Khazaka, Germany). The probe is placed in contact with the skin on the cheek of the subjects and the tonicity measurement is carried out instantaneously. The R5 tonicity values are then used for the data analysis.

[0247] The results are expressed by calculating the mean of the R5 values of all the subjects evaluated. The statistical comparisons between treatments were carried out using repeated-measurement mixed models (ANOVA). A comparison is considered to be significant for a p<0.05.

Tonicity: Variation of the R5 Parameter Compared with the First Day of Study

TABLE-US-00007 Days average p. value Day 07 0.024 0.094 Day 14 0.023 0.118 Day 28 −0.008 0.564 Day 56 0.072 0.000 Day 84 0.084 0.000 Day 168 0.090 0.000

[0248] It was noted that when composition 1 according to the invention is applied to the facial skin, the improvement in the tonicity value measured is significant compared to the initial state, as early as 56 days of treatment (p<0.001), this being up to the end of the treatment at 6 months.

[0249] Composition 1 according to the invention applied to the skin makes it possible to improve the viscoelastic properties of the skin, and in particular the tonicity of the skin, in particular of facial skin.

Firmness

[0250] Composition 1 according to the invention applied to the skin makes it possible to improve the firmness of the skin, and in particular its efficacy on the improvement of the firmness of the skin is significantly better compared to the composition of the example 4, which is a conventional emulsion (outside the invention) when it is applied to the skin.