WO2009136084A2 - Emulsifying cosmetic composition, preparation and uses - Google Patents

Abstract

The invention relates to emulsifying compositions comprising sunflower lecithin, to an anionic emulsifier of plant origin, and to a nonionic emulsifier of plant origin, and to their preparation and uses, particularly in the cosmetics field. It likewise relates to the emulsions formed from these compositions, and to any cosmetic product comprising or formed from these compositions.

Description

 EMULSIFYING COSMETIC COMPOSITION, PREPARATION AND

USES

The present application relates to an emulsifying composition, its preparation and its uses, especially in the cosmetics field. It also relates to the emulsions formed from these compositions, as well as any cosmetic product, comprising an oil-in-water type emulsion, comprising or formed from these compositions.

BACKGROUND OF THE INVENTION

Emulsions are dispersions formed from two immiscible phases in oil / water or water / oil form. It can also be multiple emulsions, for example water / oil / water or oil / water / oil. The formation of emulsions requires the use of emulsifiers, which reduce interphase stresses and avoid the melting of the droplets. Various emulsifying systems have thus been proposed in the literature, mainly based on the use of surfactant compounds. By way of example, mention may be made of the emulsifying systems described in applications WO94 / 10978; GB 1,360,021; WO2006 / 034992 and WO2007 / 031139.

US Patent 5310556 relates to conventional emulsion creams comprising, among many ingredients, sunflower oil, lecithin, and several components known for their emulsifying characteristics. US patent applications 2005/112153 and EP 0716848 relate to dermatological compositions containing sunflower oil and emulsifiers. These systems form conventional emulsions, namely emulsions in which an oily phase is dispersed in an aqueous phase in the form of oil droplets.

The patent application EP 1 151 744 relates to a cosmetic composition comprising hydrogenated lecithin and a combination of moisturizing agents, crosslinked vinyl polymers and glycol-based solvents. In this type of emulsion, Oily phase droplets are trapped within a rigid crystalline lattice distributed throughout the aqueous phase, forming a lamellar structure.

The different emulsifying systems of the prior art, however, have disadvantages related to the nature of some of their constituents, and specificities that limit their uses. The present application proposes a new emulsifying system that overcomes some of the disadvantages of existing products.

SUMMARY OF THE INVENTION

The present application proposes a new natural and versatile emulsifying system, composed mainly of materials of plant origin. More specifically, the invention describes an emulsifier composition comprising sunflower lecithin, an anionic emulsifier of plant origin and a nonionic emulsifier of vegetable origin.

The present invention also relates to the use of said emulsifying composition for the preparation of a cosmetic product.

The invention also relates to a method for preparing an emulsifying composition as described above. The invention further relates to a method of manufacturing a cosmetic product comprising an emulsifier as described above.

As will be described in the present application, the compositions according to the invention possess, by the nature of the ingredients which constitute them, not only exceptional emulsifying properties, but they are also capable of improving the hydration state of the skin and restructure the skin barrier. Moreover, the invention surprisingly shows that, while respecting certain relative proportions for the ingredients, emulsifiers adopting a completely new structure are obtained, containing droplets of fatty phase around which lamellar phases are formed, located exclusively around these elements. droplets. This original structure, different from the conventional or lamellar structure, gives particularly stable emulsions with a fluid viscosity. DETAILED DESCRIPTION OF THE INVENTION

The present invention discloses a novel emulsifier composition having improved stability and viscosity properties.

The invention derives more particularly from the combination of three constituents, of vegetable origin, which can confer on said composition a structure having new characteristics and advantageous properties. Thus, a particular object of the invention resides in an emulsifying composition comprising, relative to the total weight of the ingredients:

from 5 to 50% by weight of sunflower lecithin; from 30 to 70% by weight of anionic emulsifier of plant origin; and from 15 to 45% by weight of nonionic emulsifier of vegetable origin.

The emulsifying composition of the invention is of simple manufacture, it is stable even without preservatives, and compatible with various fatty phase qualities and with any type of active ingredient. In addition, the formation of emulsions does not require the hydration of the phospholipids. Moreover, even if the system of the invention is compatible with lamellar emulsifiers and can make it possible to form lamellar emulsions by additions of fatty acids and / or fatty alcohol, it is not a specific system of lamellar emulsions. . In particular, the emulsions formed with the aid of the composition according to the invention can adopt a hitherto unknown structure. Surprisingly, lamellar-like structures which form in the emulsions according to the invention are located exclusively around the oily phase droplets. This new structure makes it possible to obtain particularly stable emulsions with a fluid viscosity if viscosity increasing agents are not added thereto.

In addition, the composition according to the invention not only has exceptional emulsifying properties, but it is also capable of improving the state of hydration of the skin and of restructuring the skin barrier. As will be described in more detail in the following text, the compositions of the invention are compatible with any type of asset. They make it possible to obtain soft, velvety texture emulsions that are not very whitening on application and easy to spread. They make it possible to emulsify all types of fatty phases, with a particular affinity for vegetable fats.

The first constituent of compositions of the invention is sunflower lecithin. It can be implemented in hydrogenated form or not, preferably hydrogenated. Sunflower lecithin can be obtained from various sources, and in particular under the reference Solec® SF 10 from The Solae Company. Lecithins are obtained from sunflower oil. This oil can be extracted from sunflower seeds by pressure or with the help of suitable solvents. Once the oil obtained, the lecithin is extracted by degumming the oil. It can then be filtered. Like any other lecithin, it must contain at least 60% polar lipids insoluble in acetone. It contains various phospholipids including phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidic acid, the relative contents of which are different from those obtained with another lecithin such as soy lecithin. It differs from soybean lecithin because of its relative fatty acid content, it is particularly rich in oleic acid (relative content greater than 25% of fatty acids) and linoleic acid (relative content greater than 62% of fatty acids). ) as shown in Table 1. Hydrogenated lecithin can be obtained from various methods known per se. Thus, according to a usable method, sunflower lecithin is dissolved in a solvent system and then hydrogenated for 1 to 20 hours under a hydrogen pressure of 10 to 200 Kg / cm ² at a temperature of 50-90 ⁰ C and in the presence a catalyst. Hydrogenation makes it possible to improve the stability of lecithins, in particular with respect to oxidation or other degradations. The measurement of the iodine value of a lecithin is a good indication of its quality and its state of hydrogenation. In the case where the invention contains hydrogenated sunflower lecithin, the latter preferably has an iodine number of less than 20. Table 1: Chemical profile of lecithins

In a particularly advantageous manner, the emulsifying compositions of the invention comprise from 5 to 50% by weight of hydrogenated sunflower lecithin, more preferably from 5 to 30%, preferably from 5 to 25%, from 10 to 20%, and even more preferably approximately 10 to 15%, relative to the weight of the three constituents.

The second raw material of the compositions of the invention is an emulsifier of vegetable and anionic origin. It is preferably chosen from esters of glyceryl stearate. Particularly preferred is glyceryl stearate citrate (of formula C27H48O1O), which can be obtained by esterification of glyceryl stearate with citric acid. Glycerol typically comes from the hydrolysis of vegetable triglycerides. Glyceryl stearate citrate is an emulsifier without polyethylene glycol ("PEG"). Glyceryl stearate citrate can also be obtained from commercial sources, and in particular under the references Axol ^® C62 pellets, Evonik France SAS, or Dermofeel ^® GSC, from Dr. Straetmans Germany GmbH.

In a particularly advantageous manner, the emulsifying compositions of the invention comprise from 30% to 70% by weight of anionic emulsifier of plant origin, preferably from 40% to 60%, still more preferably from 50% to 55%, relative to the weight. of the three constituents. It is preferably an anionic emulsifier of vegetable origin having an HLB greater than 8. The term HLB ("Hydrophilic Lipophilic Balance") refers to the ratio between the hydrophilic part and the lipophilic moiety in the molecule (see for example "The HLB System, A Time Saving Guide to Emulsify Selection, ICI Americas Inc., 1984). It is understood that the composition according to the invention may comprise a mixture of several anionic emulsifiers of plant origin, this mixture advantageously representing 30 to 70% by weight of the total pea of the composition.

The third raw material of the compositions of the invention is an emulsifier of vegetable and nonionic origin. It advantageously has an HLB greater than 8. It is preferably chosen from polyglycerol esters. Polyglycerol esters, which are entirely vegetal in origin, compete by their performance and versatility with polyethylene glycol derivatives. The possible modulation of the hydrophilicity of the polar heads according to the degree of oligomerization of the glycerol coupled with the variability of the nature and the number of fatty chains leads to a wide range of polyglycerol esters which cover a range of HLB values included between 1 and 15 (Chailloux-Lemarie, 2004). The polyglycerol esters are derived from the reaction between a polyglycerol molecule and a fatty acid molecule. Particularly preferred is polyglyceryl-3 stearate (of formula C27H54O8), which can be prepared by reaction of a polyglycerol molecule with stearic acid. Polyglyceryl-3 stearate can also be obtained from commercial sources, including under reference Dermofeel ^® PS, Dr Straetmans GmbH.

Particularly advantageously, the emulsifying compositions of the invention comprise from 15 to 45% by weight of nonionic emulsifier of vegetable origin having an HLB greater than 8, preferably from 20 to 35%, more preferably 30 to 35% by weight. about%, based on the weight of the three constituents. It is understood that the composition according to the invention may comprise a mixture of several nonionic emulsifiers of vegetable origin, this mixture advantageously representing 15 to 45% by weight of the total pea of the composition.

A typical composition according to the invention thus comprises, relative to the weight of the three constituents: from 5 to 50% by weight of sunflower lecithin, hydrogenated or otherwise, more preferably from 5 to 30%, even more preferentially from 5 to approximately 25%;

from 30 to 70% by weight of glyceryl stearate citrate, preferably from 40 to 60%, still more preferably from 50 to 55%; and from 15 to 45% by weight of Polyglyceryl-3-Stearate, preferably from 20 to 35%, even more preferentially from 30 to 35% approximately.

In a particular embodiment, the compositions according to the invention further comprise tocopherol, preferably from 0.05 to 1% by weight relative to the total weight of the composition, more preferably from 0.1 to 0.5% included. The presence of tocopherol makes it possible in particular to improve the oxidation stability of the compositions.

Furthermore, the compositions of the invention may further comprise one or more compatible excipients or vehicles. These include dyes, consistency agents, gelling agents, preservatives, water, etc.

The compositions of the invention may be prepared by methods known per se. Thus, they are typically prepared by mixing the various constituents and recovering the composition in the desired form. In a typical process, the anionic emulsifier and the nonionic emulsifier are melted together or separately (in which case they are then mixed together at a temperature above the melting point of the two components). The mixture of the two ingredients is then heated to a temperature above 80 ^° C. The sunflower lecithin, hydrogenated or not, is then introduced into the mixture (poured in the case of a native lecithin, sprinkled in the case of a lecithin hydrogenated, with stirring). Stirring is maintained until the mixture is homogeneous and the product is cooled. The cooling of the fat mass causes its crystallization. The final appearance of the product will depend on the method of crystallization used. The compositions are advantageously in solid form, especially pellet, although other forms are possible (sticks, tablets, powder, paste, breads, granules, etc.). The emulsifying compositions of the invention are particularly useful and suitable for the preparation of oil-in-water emulsions or dispersions and cosmetic products.

Thus, a particular object of the invention relates to the use of a composition as defined above for the preparation of a cosmetic product.

Another subject of the invention relates to the use of a composition as defined above for the preparation of an oil-in-water emulsion or dispersion.

Advantageously, the compositions of the invention are used in amounts ranging from 2 to 6%, preferably from 3 to 4%, to give emulsions or final compositions. At 4%, the compositions make it possible to emulsify up to 40% of oil in an aqueous phase (4/40/56); or even 60% for an oil of very low viscosity and average polarity (see Example 4). The viscosity of the emulsion obtained is increasing with the composition rate and with the fat phase rate.

A particular object of the invention resides in a process for forming an oil-in-water emulsion or dispersion, comprising the step of adding a fatty phase or an oil to, or adding to, a fatty phase or an oil, a composition such as as defined above, preferably from 2 to 6%, more preferably from 3 to 4%, in an aqueous phase. Preferably, the fatty phase is 5 to 60%, the emulsifier is 2-6%, and the aqueous phase is 93 to 34%.

In a typical embodiment, the composition of the invention is introduced into the fatty phase. The resulting product is brought to a temperature between 70 and

80 ⁰ C, then the fatty phase is emulsified in the aqueous phase with vigorous stirring

(for example in a stator rotor). The emulsion is then cooled with gentle stirring. In a particular embodiment using a typical stirrer

Rayneri, it is possible to carry out the emulsification with a simple deflocculeuse but with a stirring as high as possible (ideally greater than 1500 rev / min).

An advantage of the compositions of the invention is that the hydration of phospholipids is not necessary, whereas it is usually required to make oil / water emulsions with lecithins.

The compositions of the invention are preferably used at a pH of between 4.0 and 8.0. They can be used in the presence of alcohol, up to 30%.

As indicated above, the invention makes it possible to obtain soft and velvety textures that are not very whitening on application, that are easy to spread. Furthermore, the invention is useful for emulsifying all types of fatty phases, with a particularly strong affinity for vegetable fats and emollients of medium polarity.

The compositions of the invention have been tested in the presence of various qualities of oils, sunscreens and pigments, without showing any particular incompatibility. They tolerate electrolytes (eg 3% NaCl or 3% Mg ₂ SO ₄ per 4% emulsifier) and can be used in the presence of glycerol esters and / or organic acids.

An emulsion at room temperature obtained in a system containing 20% of liquid oil, 76% of aqueous phase and 4% of composition according to the invention generally has the consistency of a fluid milk. The final viscosity will depend on the viscosity and polarity of the oil retained.

To obtain a firmer consistency emulsion, such as a cream, it is possible to add a consistency agent (s) and / or gelling agent (s) to the composition of the invention or to the mixture, before, during or after formation of the emulsion. In this way, it is possible to easily obtain textures of very different consistencies.

The emulsions obtained are white to beige, depending on the quality and quantity of the oils as well as the quality of the lecithin used. Another subject of the invention relates to a process for preparing a cosmetic product, comprising a step of mixing a composition as defined above with a fatty or oily phase and an aqueous phase, preferably at a rate of 2. at 6%, more preferably 3 to 4%. The cosmetic product may for example be a care or make-up product, for example of the milk, cream, foundation, body spray, mascara or eye shadow type.

The emulsifying compositions of the invention can be used to develop care products (face and body) or makeup (foundation, mascara, eyeshadow, cream, etc.) preferably in the emulsion form. oil in water. They are compatible with all types of active ingredients (such as vitamins, liposomes, filters and sunscreens, anti-aging active ingredients, anti-wrinkles, anti-oxidant, lightening, self-tanning, tanning accelerator, lifting, slimming, firming, moisturizing, exfoliating, sebum regulating, mattifying, etc.).

A test of PIE (water insensitive loss) has shown that a composition developed according to the invention used at 4% can significantly reduce the PIE of the skin. This system therefore has, in addition to its emulsifier function, an active function by improving the state of the skin barrier and avoiding dehydration of the skin.

The invention also relates to any cosmetic product, of oil-in-water emulsion type, comprising a composition as defined above. The cosmetic product generally comprises 2 - 6% of the composition according to the invention.

Other aspects and advantages of the present invention will appear on reading the examples which follow, which should be considered as illustrative and not limiting.

EXAMPLES

Example 1. Preparation of a composition of the invention

By mixing the ingredients in a suitable container, a composition comprising the following materials was prepared: 18% by weight of sunflower lecithin;

- 52% by weight of Glyceryl Stearate Citrate; and

30% by weight of Polyglyceryl-3-Stearate.

Example 2. Preparation of a composition of the invention

By mixing the ingredients in a suitable container, a composition comprising the following materials was prepared:

13% by weight of hydrogenated sunflower lecithin;

54% by weight of Glyceryl Stearate Citrate; and - 33% by weight of Polyglyceryl-3-Stearate.

It is in the form of yellow-orange pellets.

Example 3. Preparation of a composition of the invention

By mixing the ingredients in a suitable container, a composition comprising the following materials was prepared:

20% by weight of hydrogenated sunflower lecithin;

- 50% by weight of Glyceryl Stearate Citrate; and

30% by weight of Polyglyceryl-3-Stearate. It is in the form of yellow-orange pellets.

EXAMPLE 4 Study of the Fatty Phase Emulsified with 4% of an Emulsifying Composition of the Invention

The emulsifying composition described in Example 2 was used in this study.

The composition (4%) was introduced into the fatty phase at different rates indicated in Table 2, the aqueous phase constituting the remainder of the mixture. The resulting product is brought to a temperature between 70 and 80 ⁰ C, then the fatty phase is emulsified in the aqueous phase with vigorous stirring. The viscosity obtained is shown in Table 2 below, as a function of the fat phase level. Table 2

EXAMPLE 5 Study of the Viscosity of a Formula with 4% Emulsifier and 20% Fatty Phase, as a Function of the pH

The following formula was prepared under the experimental conditions described in Example 4, by varying the pH:

Emulsifier of Example 2 4%

Dicaprylyl Ether 20%

0.2% Xanthan gum

Conservative 0.5%

Water qs 100%.

The viscosity obtained is shown in Table 3 below, as a function of the pH.

Table 3

Exemple 6 : Etude de la viscosité d'une formule à 4% d'émulsionnant et 20% de phase grasse, en fonction du taux d'alcool

Example 6 Study of the Viscosity of a 4% Emulsifier and 20% Fatty Phase, as a Function of the Alcohol Content

The following formula was prepared under the experimental conditions described in Example 4, by varying the alcohol content:

Emulsifier of Example 2 4%

Dicaprylyl Ether 20%

0.2% Xanthan gum

Conservative 0.5%

Water qs 100%.

The viscosity obtained is shown in Table 4 below, as a function of the alcohol content.

Table 4

EXAMPLE 7 Study of the Viscosity of a Formula at 4% Emulsifier and 20% Fatty Phase, According to the Nature of the Fatty Phase

The emulsifying composition of Example 2 was used to emulsify various fatty phases, under the experimental conditions described in Example 4. The results obtained are shown in Table 5 below and show the great versatility of the emulsifier. the invention.

Table 5

EXAMPLE 8 Study of the Viscosity of a 4% Emulsifier and 20% Fatty Phase, as a Function of the NaCl or Mg 2 SO ₄ Level

The following formula was prepared under the experimental conditions described in Example 4, by varying the level of NaCl or Mg ₂ SO ₄ :

Emulsifier of Example 2 4%

Dicaprylyl Ether 20%

0.2% Xanthan gum

Conservative 0.5%

Water qs 100%.

The viscosity obtained as a function of the level of NaCl or Mg ₂ SO ₄ is presented in Tables 6 and 7, respectively.

Table 6

5

5

Table 7

Example 9 Study of the Viscosity of a 4% Emulsifier and 20% Fatty Phase Formula, in the Presence of Potentially Destabilizing Agents

The following formula was prepared under the experimental conditions described in Example 4 in the presence of various potentially destabilizing agents: Emulsifier of Example 2 4%

Dicaprylyl Ether 20%

0.2% Xanthan gum

Conservative 0.5%

Water qs 100%.

The viscosity is shown in Table 8.

Table 8

Example 10 - Preparation of a day cream

A day cream was prepared using the following ingredients

7

7

VS ! SODIUM ACRYLATES COPOLYMER (AND) 1.00

! HYDROGENATED POLYISOBUTENE (AND)

I POLYGLYCERYL-STEARATE (AND)

I PHOSPHOLIPIDS (AND) HELIANTHUS

I ANNUUS (SUNFLOWER) SEED OIL

I CYCLOPENTASILOXANE (ET) 2.00

I CYCLOHEXASILOXANE

D! WATER (AND) CYATHEA CUMINGII LEAF 2.00

I EXTRACT (AND) GLYCERIN (AND)

I BUTYLENE GLYCOL

E! RIBOSE 1.00

F I FRAGRANCE 0.30

BOY WUT ! POTASSIUM SORBATE 0.30

Phases A and B are separately heated to a temperature of 70-75 ^° C., with stirring. B is then added to A with vigorous stirring. It is then incorporated in the mixture AB with strong stirring. The mixture is then cooled with gentle stirring, and then the phases D, E and F are introduced when the temperature is below 35 ° C. If necessary, the pH is adapted. The resulting product is a soft and homogeneous white cream. The viscosity (Rheo ELV-8, mobile 4, 3 min, 6 rpm) is 10,000 - 20,000 mPa.s. The pH of 5.0 to 5.5 and the composition is stable after 20 minutes of centrifugation at 3000 rpm.

Example 11 - Preparation of a body spray

A body spray was prepared using the following ingredients:

Phases A and B are separately heated to a temperature of 70-75 ^° C., with stirring. B is then added to A with vigorous stirring. C is heated to 70-75 ⁰ C and kept gently stirred for 20 minutes to hydrate the phospholipids. C is then incorporated in the AB mixture. The mixture is then cooled with gentle stirring, and then the phases D, E and F are introduced when the temperature is below 35 ° C. If necessary, the pH is adapted. The resulting product is a body spray in the form of a liquid and homogeneous emulsion. The viscosity (Rheo ELV-8, mobile 4, 3 min, 6 rpm) is 4500 - 6500 mPa.s. The pH of 5.0 to 5.5 and the composition is stable after 20 minutes of centrifugation at 3000 rpm.

Example 12 - Preparation of a foundation

A foundation was prepared using the following ingredients

Phases A and B are separately heated to a temperature of 70-75 ^° C., with stirring. B is then added to A with vigorous stirring. It is then incorporated in the mixture AB with vigorous stirring. The mixture is then cooled with gentle stirring, and phases D and E are introduced when the temperature is below 35 ° C. If necessary, the pH is adapted. The resulting product is a soft and homogeneous cream. The viscosity (Rheo ELV-8, mobile 4, 3 minutes, 6 rpm) is 20,000 - 25,000 mPa.s. The pH of 5.0 to 5.5 and the composition is stable after 20 minutes of centrifugation at 3000 rpm.

Claims

An emulsifying composition, characterized in that it comprises, based on the total weight of the ingredients: from 5 to 50% by weight of sunflower lecithin; from 30 to 70% by weight of anionic emulsifier of plant origin; and from 15 to 45% by weight of nonionic emulsifier of vegetable origin. 2. Composition according to claim 1, characterized in that the sunflower lecithin is hydrogenated. 3. Composition according to claim 2, characterized in that the anionic emulsifier of vegetable origin is glyceryl stearate citrate. 4. Composition according to claim 1, characterized in that the nonionic emulsifier of vegetable origin has an HLB greater than 8. 5. Composition according to claim 4, characterized in that the nonionic emulsifier of vegetable origin is a polyglycerol ester, preferably polyglyceryl-3 stearate. 6. Composition according to any one of the preceding claims, characterized in that it comprises, relative to the total weight of the ingredients: from 5 to 30% by weight of sunflower lecithin, more preferentially from 5 to 25%; 40 to 60% by weight of anionic emulsifier of plant origin, more preferably 50 to 55% approximately; and from 20 to 35% by weight of non-ionic emulsifier of plant origin, more preferably from 30 to 35% approximately. 7. Composition according to any one of the preceding claims, further comprising tocopherol, preferably from 0.05 to 1% by weight, more preferably from 0.1 to 0.5% inclusive, relative to the total weight of the composition. 8. Composition according to any one of the preceding claims, further comprising one or more compatible excipients or vehicles. 9. Composition according to any one of the preceding claims, characterized in that it is in solid form, preferably pellet, powder, granule, dough or bread. 10. Process for preparing a composition according to any one of claims 1 to 9, comprising mixing the various constituents and recovering the composition in the desired form. 11. Use of a composition according to any one of claims 1 to 9 for the preparation of a cosmetic product. A process for forming an oil-in-water emulsion or dispersion, comprising the step of adding a fatty phase or an oil to or to a fatty phase or an oil, a composition according to any one of claims 1 to 9, preferably from 2 to 6%, more preferably from 3 to 4%. 13. A process for the preparation of a cosmetic product, comprising a step of mixing a composition according to any one of claims 1 to 9 with a fatty or oily phase, preferably in a proportion of 2 to 6%, more preferably 3 to 4%. 14. The method of claim 13, characterized in that the cosmetic product is a care product or makeup, for example milk, cream, foundation, body spray, mascara, eye shadow. 15. Cosmetic product of oil-in-water emulsion type comprising a composition according to any one of claims 1 to 9.