FR2683453A1 - Translucent water-in-silicone cosmetic emulsion enriched with active principles - Google Patents

Abstract

Water-in-silicone emulsion essentially comprising an aqueous phase mainly comprising water and at least one ethoxylated and methylated glucose ether, a fatty phase mainly comprising a first silicone having a linear chain and glycol group and a second silicone having a cyclic chain and methyl group, and hydrophilic or lipophilic active principles for producing treatment effects that influence the functioning or physiology of the skin. Use in a substantially translucent cosmetic treatment emulsion having a creamy consistency.

Description

 The invention relates to a substantially translucent water in silicone emulsion, having a creamy consistency.

 I1 turns out today that translucent, or even transparent, cosmetic compositions have cosmetic qualities which can sometimes be improved due in particular to their formulation which limits the introduction of the treating active principles, this in order to preserve their more or less "transparent" appearance. ".

 Indeed, it turns out that the effectiveness of the emulsions and their quality of transparency result from a balance between the constituents, this balance being located in a relatively narrow concentration zone and difficult to determine.

 Also, to convey active ingredients, there is often a tendency to use other types of composition than a translucent emulsion.

 The object of the invention, however, is to provide such an emulsion, by providing a solution in particular to the problem of compatibility between a tendency to transparency and the use of active treating ingredients which can reach high concentrations, without disturbing the composition nor limit its effectiveness.

 This results in an emulsion having enhanced cosmetic properties, in particular in terms of yield of the active ingredients, of stickiness and of comfort for the skin, once the emulsion has been applied.

More specifically, the emulsion of the invention is characterized in that it essentially comprises
an aqueous or hydrophilic phase comprising mainly water and an ethoxylated and methylated glucose ether,
a fatty or lipophilic phase mainly comprising a first silicone with a linear chain and with a glycol group and a second silicone with a cyclic chain and with a methyl group,
- and hydrophilic or lipophilic active ingredients to produce treatment effects influencing the functioning or physiology of the skin.

 To avoid any ambiguity, the active principles or ingredients of a cosmetic composition will already be defined as substances which, when applied in particular to the skin, produce physical, physico-chemical, chemical or biochemical effects (see also subjective) influencing the functioning and / or physiology of the skin or mucous membranes and their appendices, this with a minimum of side effects in the organism (see definition of "Cosmetics and toiletries" Ellis Horwood- 1991 page 41 ).

 We can consider that it is practically any raw material of animal or synthetic vegetable origin entering into the composition of a cosmetic, usually other than excipients, and having biological properties favorable to the human epidermis, such as hydration properties of the surface layers of the epidermis, cell regeneration, or softening, emollient, cleansing, soothing properties, etc.

 This therefore concerns vitamins as well as essential fatty acids, vegetable oils (for example macadamia, sweet almond, borage, ...), animal oils (for example squalane), enzymes (SOD) glycosaminoglycans (such as hyaluronic acid), proteins (such as collagen, elastin, ...) more or less purified.

 In practice, these active ingredients are often used to give the skin hydration properties (glycosaminoglycans, essential fatty acids, ...), flexibility and elasticity (vegetable oil, protein, ...) or protection. against a metabolic dysfunction or against the harmful effects of ultraviolet radiation.

 The percentages used of these active ingredients are variable depending on the nature of the active ingredient considered and its degree of purification.

 In practice, the formulation of these products is all the more delicate as it exposes active principles which are often incompatible on the physical or chemical level (for example a hyaluronic acid of water-soluble nature and a vitamin F of fat-soluble nature) and that 'It must meet drastic cosmetic criteria, such as acceptability in terms of application, comfort and compatibility with other cosmetic products, such as moisturizing emulsions by day or nourishing by night.

 Thus, in the present case, it appeared necessary for the chemical environment of the active ingredients to include a glucose ether, and preferably methyl gluceth 20, advantageously representing between 30 and 40% by weight of the emulsion.

Essentially, the function of this glucose ether is that of a texture agent, that is to say a thickener intended to give the aqueous phase of the composition the desired viscosity, which will preferably be between approximately 250,000 and 400,000 centipoises (cp), i.e. 250 to 400
Not.

 For the effectiveness and the stability of the emulsion, the first and second silicones of the fatty phase will preferably be of the copolyol type of dimethicone and cyclomethicone respectively, the first silicone being used essentially as surfactant, while the second is more particularly intended to constitute the oily base.

 Dimethicone copolyols are polymers of dimethylsiloxane comprising side chains of polyoxyethylene or polyoxypropylene.

 As for cyclomethicones, these are volatile dimethyl polysiloxane compounds.

 It will be noted that the cyclomethicones also have the advantage of acting effectively as a skin cleansing agent, without providing a feeling of heating.

 Advantageously, these two silicones together represent between about 10 and 30% by weight of the emulsion.

Thus, this emulsion will result from a balance between three essential components
- said first and second silicones (representing between 10 and 30% by weight of the emulsion),
- ethoxylated and methylated glucose ether (between 30 and 40% approximately) and,
- water (between about 35 and 55% by weight).

 In this way, a very fine water in silicone emulsion can be obtained, so fine that it can be almost transparent (droplet size which can reach dimensions of the order of a nanometer).

 However, in certain applications, mineral fillers such as titanium oxide can be added to it, to make the emulsion tend towards opalescence, while retaining the cosmetic and consistency qualities of a cream. Contents of 0.1 to 0.5% by weight are recommended.

 By way of indicative example, two formulas of a cosmetic composition in accordance with the invention will be found below, the contents having been expressed as a weight / weight percentage.

 Example 1: moisturizing day cream.

Water QSP 100
Cyclomethicone and
dimethicone copolyol 18 to 22
Methyl gluceth 20 32 to 37
Vegetable oil 0.4 to 0.6%
Critalline protein 0.5 to 0.7%
Vitamin E 0.3 to 0.8%
Sodium silanol lactate 0.75 to 1.25%
0.15% W filter
Antibacterial preservatives 0.20%
In this formula, it will be noted as active agents: crystalline proteins, vitamins E and sodium silanol lactate.

Example 2 Protective Cream "Opalescent" Water QSP 100 Cyclomethicone and
dimethicone copolyol 18 to 22 Methyl gluceth 20 32 to 37. Urea 0.3 to 0.7%. Preservatives 0.20% Filter W 0.15% Glycerin 8 to 12 Crystalline protein 0.4 to 0.7%. Liquid chitin 0.8 to 1.2%. Polyglyceryl methacrylate 10 to 15. TiO2 0.15 to 0, 5%
In this second formula, it will be noted as active "treatment" agents, in particular in their emollient and / or hydrating action: urea, glycerin, crystalline proteins, liquid chitin and polyglyceryl methacrylate.

Claims (7)

 1 - Cosmetic emulsion substantially translucent water in silicone, of creamy consistency, essentially comprising  an aqueous or hydrophilic phase comprising mainly water and at least one ethoxylated and methylated glucose ether,  a fatty or lipophilic phase comprising mainly a first silicone with a linear chain and with a glycol group and a second silicone with a cyclic chain and with a methyl group,  - and hydrophilic or lipophilic active ingredients to produce treatment effects influencing the functioning or physiology of the skin.  2 - Emulsion according to claim 1 characterized in that the glucose ether is methyl gluceth 20 representing about 30 to 40% by weight of the emulsion.  3 - Emulsion according to claim 1 or claim 2 characterized in that the first and second silicones are respectively copolyol of dimethicone and a cyclomethicone, together representing between about 10 and 30% by weight of the emulsion.  4 - Emulsion according to any one of the preceding claims, characterized in that the water of the aqueous or hydrophilic phase represents between approximately 35 and 55% by weight of the emulsion.  5 - Emulsion according to any one of the preceding claims, characterized in that it also comprises mineral fillers to make the emulsion tend towards opalescence.  6 - Emulsion according to any one of the preceding claims, characterized in that it essentially consists of the following components, the contents of which are indicated as a weight / weight percentage Water QSP 100 Cyclomethicone and  dimethicone copolyol 18 to 22. Methyl gluceth 20 32 to 37 Vegetable oil 0.4 to 0.6% Critalline protein 0.5 to 0.7% Vitamin E 0.3 to 0.8% Sodium silanol lactate - 0.75 to 1.25% UV filter 0.15% Preservatives 0.20%  7 - Emulsion according to any one of claims 1 to 5 characterized in that it consists essentially of the following components whose contents are indicated in weight / weight percentage Water QSP 100 Cyclomethicone and  dimethicone copolyol 18 to 22 Methyl gluceth 20 32 to 37. Urea 0.3 to 0.7%. Preservatives 0.20% Filter W 0.15% Glycerin 8 to 12 Crystalline protein 0.4 to 0.7%. Liquid chitin 0.8 to 1.2% Polyglyceryl methacrylate 10 to 15. TiO2 0.15 to 0.5 %