EP2706974A2

EP2706974A2 - Topical cosmetic composition containing an improved pro-penetrating system

Info

Publication number: EP2706974A2
Application number: EP12728673.0A
Authority: EP
Inventors: Jean-Noël THOREL
Original assignee: Individual
Current assignee: Individual
Priority date: 2011-05-12
Filing date: 2012-05-14
Publication date: 2014-03-19
Also published as: WO2012153075A2; WO2012153075A3; FR2975003B1; FR2975003A1

Abstract

The invention relates to a topical cosmetic composition comprising a single active ingredient that can interact with the skin, including the scalp, in order to treat a skin dysfunction, and a pro-penetrating system containing ethanol and propanediol. The composition is characterised in that: ethanol represents between 1 and 10 wt.-% and, advantageously, between 2 and 5 wt.-% of the composition; and propanediol represents between 1 and 20 wt.-% and, advantageously, between 5 and 10 wt.-% of the composition.

Description

TOPICAL COSMETIC COMPOSITION CONTAINING A SYSTEM

IMPROVED PROPENETRANT

The invention relates to a topical cosmetic composition having improved penetration of the asset it contains, through the skin. More specifically, the invention relates to a cosmetic composition comprising an improved propenetrating system.

One of the main functions of the skin is the barrier function that works in both directions. It prevents the loss of water, electrolytes and other constituents of the human body and prevents the penetration of environmental molecules. This barrier function is however not infallible and it is this relative permeability that is used for the passage of assets through the skin. Essentially, the penetrating agents improve the passage of the skin by reducing the resistance of the stratum corneum. One of the objectives of the invention is to develop a cosmetic formulation containing an asset penetration system which is particularly effective and which represents a smallest possible proportion of the final composition.

Another objective is to propose a cosmetic formulation that contains a penetration system having good tolerance to the skin.

Another goal is to develop a penetration system that can accommodate as many assets as possible. Another object of the invention is to have cosmetic formulations comprising the fewest possible ingredients, so as to avoid as much as possible the harmful chemical interactions between the active agents and the excipients.

Another object of the invention is to provide cosmetic compositions containing the purest ingredients possible, including at least one active, preferably a single active:

- used at its optimum dose,

formulated stably,

in a galenic environment favorable to its interaction with its skin target (s).

The Applicant has indeed found that the combination of these three conditions favored the effectiveness of the asset. US Pat. No. 5,962,000 A (EP610511A1) and in particular Examples 2.7 and 3.7 describe cosmetic compositions containing at least two active ingredients respectively vitamin A and mannose or vitamin A and dexamethasone. Ethanol and propanediol are used separately (see process) as a solubilizing agent.

Document FR-A-2 898 499 describes an oil-in-water type emulsion comprising in particular a steroidal anti-inflammatory agent and a propenetrating system consisting of propylene glycol at 37.5% by weight and ethanol at 5% by weight. The use of high doses of propylene glycol is often responsible for intolerance reactions and discomfort (irritation, itching, redness ...) found on the subjects treated.

No. 6,861,060 B1, in particular example 4, describes a colloidal formulation containing lipid particles in suspension in a major aqueous phase, chlorhexidine being distributed between the aqueous phase and the lipid particles. A mixture of propanediol and ethanol is used to dissolve lipid (lecithin), active and surfactants. No application of this composition is described. US 2006/117995 A discloses a preparation for coloring the skin (make-up) containing pigments soaked in water. Example 2 refers to the combination in a complex composition of ethanol, propanediol and D-panthenol. Ethanol and propanediol are used as humectant. D-Panthenol is used as a "care substance" because of the low concentration at which it is used. It is not used as an asset.

US 2003/186826 A1, particularly Example 7, discloses a paste in the form of premix containing a surfactant (TEA) mixed with various ingredients including ethanol and propanediol. Alcohols are used to promote the solubilization of surfactants The use of the premix is not mentioned.

To fulfill all the objectives and to solve the problems mentioned above, the Applicant has developed a topical cosmetic composition comprising an active ingredient and a propenetrating system, itself comprising ethanol and propanediol, the addition of these two ingredients. wherein the composition is preferably free of polyorganosiloxanes modified with polyoxyalkylenes. In a particular embodiment:

the ethanol represents between 1 and 10%, advantageously between 2 and 5% by weight of the composition,

propanediol represents between 1 and 20%, advantageously between 5 and 10% by weight of the composition.

Advantageously, the propenetrating system consists exclusively of:

ethanol representing between 1 and 10%, advantageously between 2 and 5% by weight of the composition,

of propanediol representing between 1 and 20%, advantageously between 5 and 10% by weight of the composition.

To avoid any harmful interaction between actives, the composition contains only one active agent, which is able to interact with the skin to treat a skin dysfunction.

The term "a single active agent" designates a characterisable active substance capable of interacting with the skin to treat a cutaneous dysfunction, the active ingredient being:

or a pure molecule obtained by synthesis, by biotechnology, advantageously the molecules contained in the skin, including for example but not limited to, vitamins, trace elements, mineral salts, enzymes, peptides, proteins, sugars and sugar derivatives, fatty acids and fatty acid derivatives,

a pure molecule obtained by purification from a plant,

a total plant extract, that is to say a mixture of molecules of interest extracted from a plant,

a plant extract titrated to a specific molecule.

By "cutaneous dysfunctions" is meant in particular but not limited to, the first wrinkles and fine lines, expression lines, wrinkles installed, loss of firmness, shine (excess of sebum), black spots, the grain of irregular skin, dilated pores, pimples, acne, pigment spots, hyperpigmentation, irritation, tingling, warming, redness, rosacea, dryness (tugging, discomfort, squasms ...), drought extreme (xerosis, atopy, scab, eczema ...), calluses, rough skin, chapped skin, lesions (blues, scars, edema ...). The composition is topical in that it is intended to be applied to the skin, including the scalp excluding mucous membranes.

In practice, the active ingredient represents between 0.001% and 20% by weight of the composition, advantageously from 0.5% to 10% by weight.

In order to allow precise administration of the active ingredient, the composition of the invention is advantageously dispensed by means of a dropper or a pump bottle. In this hypothesis, the composition has a viscosity of between 250 and 2000, depending on the dosage form, advantageously 400 and 850 cps. (The viscosity measurement is carried out at 25 ° C. on a BROOKFIELD DV-II + PRO viscometer, with a mobile size 3 rotating at a speed of 60 rpm). Advantageously, the composition is in the form of an emulsion or a gel. "Emulsion" denotes an O / W emulsion whose particle size is greater than 1 micrometer.

In this form of administration, the composition contains in practice at least 60%, advantageously at least 70% by weight of water.

As will be seen later, the combination of ethanol and propanediol improves the penetration of the active ingredients in the skin with respect to the same active ingredients, without a penetration system, in the form of a solution or a conventional emulsion. .

Advantageously, the propanediol is obtained by a fermentation process carried out on a renewable biological material. In other words, it is of plant origin.

The Applicant has further demonstrated that it is possible to further improve the penetration of the active ingredient by adding, with ethanol and propanediol, urea and possibly lactic acid or one of its salts. Advantageously, the urea represents between 1 and 4% by weight of the composition while the lactic acid or one of its salts represents between 0.5 and 1.5% by weight of the composition.

As already stated, one of the objectives is to incorporate in the stable pharmaceutical composition the least possible ingredients while having a composition as pure as possible in terms of active ingredients, and applicable to the skin. In practice, the composition contains, in addition to the active ingredient and the propenetrating system, only excipients participating in the formulation of the composition, in particular in the form of gel or emulsion. The composition of the invention may thus contain, depending on the case:

a fatty phase representing between 2 and 20% by weight, preferably between 3 and 10% by weight of the composition, and / or

a gelling agent representing between 0.1 and 2%, preferably between 0.1 and 1% by weight of the composition.

In a preferred embodiment, the composition contains, in addition to the active ingredient:

ethanol representing between 2 and 5% by weight of the composition,

propanediol representing between 5 and 10% by weight of the composition,

- Urea advantageously representing between 1 and 3% by weight of the composition, lactic acid or a salt representing preferably between 0.5 and 1% by weight of the composition.

Advantageously, the propenetrating system consists exclusively of:

ethanol representing between 2 and 5% by weight of the composition,

of propanediol representing between 5 and 10% by weight of the composition, urea advantageously representing between 1 and 3% by weight of the composition, lactic acid or a salt thereof advantageously representing between 0.5 and 1% by weight; weight of the composition.

The water used in the compositions of the invention may be demineralized or osmosis water, thermal water or water which has been subjected to a physical treatment and whose composition has been progressively enriched with mineral salts, said water being characterized by bioelectronic parameters (pH, conductivity, rH).

The subject of the invention is also the use of the propenetrating system described above in a topical cosmetic composition described above. In particular, the cosmetic composition contains only one active ingredient, the propenetrating system as well as formulation excipients, in particular making it possible to obtain a gel or an emulsion.

The invention and the advantages thereof will be apparent from the following examples.

Figure 1 is a graph showing the improvement of caffeine penetration through the skin when administered in the presence of the propenetrating system of the invention. Figures 2a to 2c are histological sections of frozen skin explant models after application of 3 separate formulations of caffeine C1 (Fig. 2a), C2 (Fig. 2b), C3 (Fig. 2c). Example 1

The purpose of this example is to compare the diffusion of caffeine 2% in 3 different environments through human skin, on Franz cells. 3 formulations were tested:

Condition No. 1 (Cl): Caffeine 2% solubilized in the absence of a propenetrating vector Condition N ° 2 (C2): Caffeine 2% in a conventional O / W emulsion

Condition N ° 3 (C3): Caffeine 2% in the pro-penetrating vector of the invention

Condition No. 4 (C4): Caffeine 2% in emulsion C2 containing the pro-penetrating vector identical to C3 a / measurement of cutaneous absorption of caffeine

Method used

The measurement of cutaneous absorption of caffeine is carried out ex vivo using Franz cells. All the experimental conditions were defined using OECD guidelines. The explants used are from frozen human skin of the same donor. The explants were placed on passive diffusion Franz cells and the products were applied semi occlusively. Before applying the products to be evaluated, the skin integrity of each cell is verified by the measurement of the PIE.

For each cell a defined amount of Cl to C4 products is then deposited on the surface of the skin using a positive displacement pipette. Each product is deposited on 3 cells of Franz distributed randomly on 4 trays. The recipient fluid contains physiological saline maintained at 32.5 ° C by a thermostatic circuit.

For each cell, a sample of recipient fluid was taken after Oh, 4h, 6h, 10h and 24h of contact with the products to be evaluated. The products tested

For each condition tested, the good solubilization of caffeine was monitored and a determination of its concentration in the formulas Cl, C2, C3, and C4 was performed before the application of the products on the explants. All formulas are adjusted to pH 7.

Tables of composition of formulas Cl, C2 and C3, C4 integrating 2% of caffeine:

at qs

C3 Caffeine 2%

0.5% xanthan gum

Propanediol 10%

Ethanol 5%

Conservatives 1%

(Leuconostoc / Radish Root Ferment Filtrate + Potassium sorbate - Sodium benzoate)

NaOH 0.001%

Water qs

at qs

Determination of caffeine

The different samples are stored in tubes identified at -20 ° C. The caffeine is then assayed in the samples by HPLC.

Results analysis

The cumulative amounts of caffeine measured at 24 hours in the recipient compartment correspond to the dose of caffeine absorbed. The results are expressed as a percentage of the actual amount of caffeine applied to each cell and represent the average of the data obtained on 3 explants treated under the same conditions.

Figure 1 represents the total amount of caffeine assayed in the recipient compartment after 24 hours of application of the products. The results are expressed as a percentage of the dose of caffeine applied to each explant and represents the average obtained on 3 cells.

As shown in this figure, the formulation C3 corresponding to the formulation of the invention makes it possible to improve the penetration of caffeine through the stratum corneum with respect to the control C1 or to a conventional formulation C2. The propenetrating role of the C3 formulation with respect to caffeine is confirmed by comparing C4, in which the propenetrating system is formulated in the form of an emulsion with C2, corresponding to the same formulation without a propenetrating agent. The dose of caffeine that has penetrated is higher with C4 than with C2. b / Tolerance of the propenetrating system of the invention vis-à-vis the skin

An explant of each series is preserved for the realization of histological sections allowing to control the cutaneous integrity. After fixation, paraffin impregnation, the 5μιη sections are made and stained with a Masson trichrome stain.

Interpretation of the cuts:

When the stratum corneum (SC) is well laminated, it means that it is properly hydrated. The delipidation of the skin as well as the drought diminish this aspect and the SC becomes more compact. The aggression of the skin by irritating products or UV causes the keratinization of SC. It becomes more compact and more impervious.

Figure 2a corresponds to the histological section of the explant treated with the composition Cl.

Figure 2b corresponds to the histological section of the explant treated with the composition C2. Figure 2c corresponds to the histological section of the explant treated with the composition C3.

The results are grouped in the following table:

(-) little, slightly; (+) enough, moderately; (++) quite clearly, quite well, well, clearly

These data make it possible to observe that, with respect to the composition Cl, the treatment C3 does not alter the qualities of the stratum corneum. In other words, the histological sections clearly show the satisfactory tolerance of the propenetrating system of the invention vis-à-vis the skin. Example 2

Gel

% in weight

Panthenol 5.00

Propanediol 5.00

Ethanol 2.00 gelling agents 0.45 pH adjusters 0.22 preservatives 2.15

Water 85.18

Gel

% in weight

Ectoine 3.00

Propanediol 5.00

Ethanol 5.00

Urea 2.00

Sodium lactate 1.00 gelling agents 0.50 pH adjusters 3.54 preservatives 2

Water 77.96 Emulsion

% in weight

Bisabobol 0,20

Propanediol 5.00

Ethanol 2.00 gelling agents 0.45 adjusters of H 0.32 emulsifiers 2.50 preservatives 2.10

Fat phase 7

Water 80.43

Emulsion

% in weight

Andrographis Paniculata Leaf Extract 0,10

Propanediol 5.00

Ethanol 5.00

Urea 2.00

Sodium Lactate 1.00 gelling agents 0.45 pH adjusters 4.04 emulsifiers 2.70 oily phase 5.00 preservatives 1.90

Water 72.81

Claims

1 / A topical cosmetic composition comprising a single active agent, which is capable of interacting with the skin, including the scalp, to treat a cutaneous dysfunction and a propenetrating system comprising ethanol and propanediol, characterized in that: ethanol represents between 1 and 10%, advantageously between 2 and 5% by weight of the composition,

Cosmetic composition according to Claim 1, characterized in that the propenetrating system consists exclusively of:

- Propanediol representing between 1 and 20%, preferably between 5 and 10% by weight of the composition,

3 / Composition according to one of the preceding claims, characterized in that the active is a characterizable active substance capable of interacting with the skin to treat a cutaneous dysfunction, the asset being:

either a pure molecule obtained by synthesis or by biotechnology,

a pure molecule obtained by purification from a plant,

a total plant extract,

either a titrated plant extract.

4 / Composition according to one of the preceding claims, characterized in that the active is between 0.001% and 20%> by weight of the composition, preferably from 0.05%> to 10%. 5 / Composition according to one of the preceding claims, characterized in that it has a viscosity of between 250 and 2000 cps, preferably between 400 and 850 cps.

6 / Composition according to one of the preceding claims, characterized in that it contains at least 60%>, preferably at least 70%> by weight of water. 7 / Composition according to one of claims 1 or 3 to 6, characterized in that the propenetrating system further contains urea, preferably representing between 1 and 4% by weight of the composition. 8 / Composition according to one of claims 1 or 3 to 7, characterized in that the propenetrating system further contains lactic acid or a salt thereof, preferably representing between 0.5 and 1, 5% by weight of the composition.

91 Composition according to one of the preceding claims, characterized in that it further contains only formulation excipients for obtaining an emulsion or a gel.

10 / A composition according to claim 9, characterized in that when it is in the form of a gel, it further contains a gelling agent representing between 0, 1 and 2%, preferably between 0.1 and 1% by weight of the composition.

1 / A composition according to one of claims 9 or 10, characterized in that when it is in the form of an emulsion, it further contains a fatty phase, representing 2 and 20%, advantageously between 5 and 10% by weight of the composition.

12 / Composition according to one of the preceding claims, characterized in that it contains:

ethanol representing between 2 and 5% by weight of the composition,

propanediol representing between 5 and 10% by weight of the composition,

urea, representing between 1 and 3% by weight of the composition,

lactic acid or a salt thereof representing between 0.5 and 1.5% by weight of the composition. 13 / Composition according to claim 1, characterized in that the propenetrating system consists exclusively of:

ethanol representing between 2 and 5% by weight of the composition,

of propanediol representing between 5 and 10% by weight of the composition, urea preferably representing between 1 and 3% by weight of the composition, - lactic acid or a salt thereof advantageously between 0.5 and 1% by weight. weight of the composition. 14 / Use of a propenetrating system according to one of claims 1 to 13 in a topical cosmetic composition.

15 / Use according to claim 14, characterized in that the composition contains only one active agent, which is capable of interacting with the skin, including the scalp to treat cutaneous dysfunction.