Emulsifying compositions based on fatty alcohol and alkylpolyglycosides

ES 2 392 945 T3

DESCRIPTION

Emulsifying compositions based on fatty alcohol and the phosphoric ester of these alcohols.

The subject of the present invention is particular emulsifying compositions that find application, in particular, in the cosmetic field.

Phosphoric esters of fatty alcohols, especially alkyl phosphates prepared from a fatty alcohol having 14 to 18 carbon atoms, are known to be emulsifiers. Polo et al. report in DCI (September 1999), 26-34 and 82-84, on the use of cetylphosphates as emulsifiers in cosmetics. Miller et al., In Colloids and Surface A: Physicochemical and Engineering Aspects, 152 (1999), 155-160, report the preparation of stable emulsions suitable for cosmetics and based on mixtures of fatty alcohols and their corresponding phosphoric acids.

Cosmetic formulators are constantly looking for new emulsion touches that do not have the disadvantage of being heavy. French patent application FR-A-2 762 317 describes, in particular, associations of alkylpolyglycosides having 20 or 22 carbon atoms with alcohols having 20 or 22 carbon atoms which lead to low-fat and evanescent emulsions, but which, for certain skin types, they are still considered too oily. One of the problems to be solved consists, therefore, in having emulsions that present a cosmetic touch superior to that of traditional emulsions that combine rapid penetration, a light and non-greasy touch and a sensation of freshness.

It is known that aqueous continuous phase emulsions have a weak resistance to water and the formulator tries to overcome this defect by combining its emulsifying system with additives such as hydrophobic polymers (ANTARON, GANEX, DERMACRYL LT79, GLOSSAMER) and / or co-emulsifiers, especially cetylphosphates such as those in the AMPHISOL range. These additives leave a significant residual film on the skin. Another problem is to have emulsions that have better resistance to water combined with the absence of the sensation of residue.

The make-up emulsions (make-up bases, masks, cream eyeshadows) of continuous aqueous phase are mainly formulated based on stearic acid or stearic acid derivatives (PEG stearate, glyceryl stearate). The stabilization of the mineral loads in these emulsions is a critical point: the tendency is to obtain a re-agglomeration of the pigments as time passes, which compromises the smooth and uniform texture (grains at the time of application or migration of pigments within the product with the appearance of streaks or colored streaks). Consequently, the stabilizing systems of the aqueous phase, associated with the emulsifying system, are technically complex and most of the time include the presence of at least two polymers (of synthetic or natural origin). Furthermore, these aqueous continuous phase emulsions have the drawback of exhibiting significant migration phenomena on the skin throughout the day. Finally, due to the nature and performance of the emulsifiers used, these aqueous continuous phase emulsions are generally formulated at a pH close to 7, that is, a pH clearly higher than the average skin pH (5.5). .

Another problem consists in having emulsions that have better makeup strength or resistance.

Another problem consists in formulating emulsions in which the fillers and / or pigments that may be present are easily and durably stabilized with a minimal addition of stabilizers in the aqueous phase.

Another problem consists in formulating makeup emulsions containing pigments, especially titanium dioxide, at a pH close to the average skin pH, in particular between 5 and 6.

Unexpectedly, it has now been discovered, and it is the basis of the invention, that the association of an alcohol having 20 or 22 carbon atoms and a phosphate alcohol having 20 or 22 carbon atoms allows: (i) to obtain emulsions with an improved feel; (ii) improve the water resistance of emulsions and (iii) improve makeup emulsions.

Thus, according to a first aspect, the object of the invention is an emulsifying composition consisting of, for 100% of its mass:

- 10 to 90% by weight, preferably 15 to 90% by weight and more preferably still, 30 to 70% by weight of arachidyl alcohol and / or behenyl alcohol; Y

- 90 to 10% by weight, preferably 85 to 10% by weight and more preferably still, 70 to 30% by weight, of phosphoric ester of arachidyl alcohol and / or of phosphoric ester of behenyl alcohol (both hereinafter referred to as in the text "phosphate alcohols")

By "phosphoric ester of arachidyl and / or behenyl alcohol" is meant a monoester, a diester, a triester or a mixture in any proportions of mono, di or triester of the alcohol in question.

ES 2 392 945 T3

The composition according to the invention makes it possible very easily to formulate emulsions, especially make-up emulsions and sun emulsions.

Thus, according to a second aspect, the object of the invention is the use of the previously described composition as an emulsifying agent for the preparation of emulsions.

According to a third aspect, the invention also relates to an emulsion containing the previously described emulsifying composition. This composition generally represents from 0.2 to 10% by weight relative to 100% of the mass of the emulsion.

The emulsion also comprises, for 100% of its mass, from 1 to 50% by weight, preferably from 5 to 35% by weight and, more preferably still, from 5 to 25% by weight, of a fatty phase made up of one or several oils and by one or more waxes.

Advantageously, the oil is chosen from the following oils:

- oils of vegetable origin, such as sweet almond, copra, castor, jojoba, olive, rapeseed, peanut, sunflower, wheat germ, corn germ, soybean, cotton, alfalfa, poppy, pumpkin, evening primrose, millet, barley, rye, safflower, cashew, passionflower, hazelnut, palm, shea butter, apricot kernel oil, oil calophyllum, sysymbrium oil, avocado oil, calendula oil;

- vegetable oils and their ethoxylated methyl esters;

- oils of animal origin, such as squalene and squalane;

- mineral oils, such as paraffin oil, petroleum jelly and isoparaffins;

- synthetic oils, especially fatty acid esters such as butyl myristate, propyl myristate, cetyl myristate, isopropyl palmitate, butyl stearate, hexadecyl stearate, isopropyl stearate, octyl stearate, isocetyl stearate, dodecyl, hexyl laurate, propylene glycol dicaprylate; esters derived from lanolic acid, such as isopropyl lanolate, isocetyl lanolate; monoglycerides, diglycerides and triglycerides of fatty acids such as glycerol triheptanoate, alkylbenzoates, polyalphaolefins, polyolefins such as polyisobutene, synthetic isoalkanes such as isohexadecane, isododecane, perfluorinated oils and silicone oils.

This oil can also be chosen from fatty acids, fatty alcohols, waxes of natural or synthetic origin and, more generally, any fatty body of vegetable, animal or synthetic origin.

Advantageously, the wax can be chosen from solid fatty substances at room temperature, such as, for example: beeswax, carnauba wax, candelilla wax, ouricuri wax, Japan wax, cork or sugar cane fiber wax, paraffin waxes, lignite waxes, microcrystalline waxes, lanolin wax, ozokerite, polyethylene wax, hydrogenated oils, silicone waxes, vegetable waxes, fatty alcohols and fatty acids solid at room temperature and solid glycerides at room temperature.

The emulsion according to the invention can also comprise up to 10% by weight of a stabilizing agent, such as for example: magnesium silicate, aluminum silicate; xanthan gum, acacia gum, locust bean gum, scleroglucan gum, gellan gum; alginates; cellulose and cellulose derivatives; clays; starches and starch derivatives; acrylic acid polymers and copolymers; acryloyldimethyltaurate polymers and copolymers; polyvinylpyrrolidone; polymers and copolymers of acrylamide and polyurethanes.

In general, the emulsion according to the invention may also contain up to 10% by weight of one or more additives commonly used in cosmetics and chosen from:

- co-emulsifiers such as, for example: fatty acids; ethoxylated fatty acids; sorbitol fatty acid esters; ethoxylated fatty acid esters; polysorbates; polyglycerol esters; ethoxylated fatty alcohols; sucrose esters; alkylpolyglycosides; sulphated and phosphate fatty alcohols;

- dispersants commonly used in cosmetics, especially: lauryl sulfate, lauryl ether sulfate, octenyl sulfosuccinate, lauryl sarcosinate; dimethicone polyolphosphate, such as the product marketed under the name PECOSIL® PS100; acrylic polymers and copolymers, such as those sold under the name AVALURE®; lauroylamino acids such as the product marketed under the name PROTEOL OAT®;

- preservatives commonly used in cosmetics;

- perfumes or other additives with a perfuming function (such as, in particular, essential oils and waxes);

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- DHA; active anti-wrinkle, moisturizing, soothing, anti-free radicals, antioxidants, sebum regulators; Mineral salts; vitamins; phytosterols; polyphenols and sphingolipids.

According to an advantageous embodiment, the emulsion according to the invention is a make-up emulsion. In this specific case, the emulsion also comprises, from 0.5 to 50% by weight, preferably from 2 to 35% by weight, of pigments and / or organic or inorganic fillers.

These pigments and / or fillers can be laminar or spherical and without particular limitation regarding their granulometry. As an example, the following may be mentioned in particular: poly (methyl methacrylate); cross-linked copolymers of methacrylic acid; nylon; poly (beta-alanine); polyethylene; teflon; lauroillysin; alkylamino acid, starch, PTFE powders; hollow microspheres such as those marketed under the names EXPANCELL® or POLYTRAP®; silicone resin microbeads; titanium dioxide; zinc oxide; iron oxide (black, red, yellow); iron titanate; carbon black; chromium oxide; chromium hydroxide; zirconium oxide; cerium oxide; cobalt titanate; ultramarine; Prussian blue; mica-titanium; bismuth oxychloride; essence of the orient or pearl; talcum powder; aluminum powder; copper powder; gold dust; mica; sericita; kaolin; phlogopite; synthetic mica; lepidolite; biotite; vermiculite; calcium carbonate; magnesium carbonate and hydroxycarbonate; Aluminum silicate; barium silicate; calcium silicate; magnesium silicate; Strontium Silicate; silica and silica microspheres; ceramic and glass microspheres; zeolites; hydroxyapatite; metal salts of tungstenic acid; barium sulfate; cast; calcium phosphate; fatty acid soaps of metal; boron nitride; photochromic pigments; interference pigments. These fillers may have undergone surface treatment.

The makeup emulsion according to the present invention can also include up to 20% by weight, preferably up to 10% by weight, of one or more cosolvents, such as glycerol, sorbitol, PEG, monopropylene glycol, butylene glycol, isoprene glycol, methyl-2-propanediol. -1.3, ethanol and hexylene glycol.

According to another advantageous embodiment, the emulsion according to the invention is a solar emulsion. In this specific case, the emulsion includes, for 100% of its mass, from 1 to 40% by weight, preferably from 1 to 20% by weight, of one or more organic or inorganic filters or sun screens; and up to 30% by weight, preferably up to 10% by weight, of a water resistant agent.

The emulsion according to the invention may also contain a sufficient amount of a base such as soda, potash, ammonia, triethanolamine, tetrahydroxypropylethylenediamine, trishydroxyaminemethane or aminomethylpropanol, to adjust the final pH of the emulsion between 3 and 10.

Naturally, the sum of the amounts of the different constituents of the emulsion according to the invention is equal to 100%.

The emulsions according to the invention can be prepared according to the procedure described below.

The aqueous phase, optionally containing the cosolvent (s) and the base, is heated to a temperature of 70 to 85 ° C. This aqueous phase contains, where appropriate, fillers and / or pigments, which may have been previously ground; it also contains stabilizing agents, dispersants, as well as preservatives, perfumes and other active ingredients.

In parallel, the fat phase containing the emulsifying composition, the oils and / or the waxes, is heated to an identical temperature of 70 to 85 ° C.

The two phases are then mixed and emulsified using a rotor-stator type apparatus (SILVERSON laboratory mixer or OLSA, rAyNERI or BECOMIX industrial apparatus). After a few minutes of emulsification, the emulsion cools down with moderate stirring.

The invention is illustrated with the aid of the following examples.

EXAMPLE 1: Synthesis of an emulsifier according to the invention

50 kg of alcohol (mixture of alcohols of 20 and 22 carbon atoms in a 70/30 ratio) are introduced into a reactor preheated to 70 ° C, under a slight nitrogen sparge. Once the mixture of alcohols is melted, 3.88 kg of phosphoric anhydride are gradually added. The reaction medium is kept 4 hours and 30 minutes at 85 ° C and then emptied.

The product obtained has the following characteristics:

Appearance C 20 & C 22 Alcohol Acid Number White Solid

90.4 g KOH / g

46,0 %

ES 2 392 945 T3 alcohol of 20 and 22 carbon atoms phosphated 54.0%

To demonstrate the invention, the emulsifiers listed in Table 1 are tested. Emulsifier C is an emulsifier according to the invention. The others are for comparison.

TABLE 1

<td></td><td>EMULSIFIER</td>

<td>TO</td><td>Phosphated carbon-16 alcohol + carbon-16 and carbon-18 alcohol mixture (50/50)</td>

<td>B</td><td>C16 phosphate alcohol + C 20 and C22 alcohol mixture (50/50)</td>

<td>C (example 1)</td><td>Mixture of alcohols of 20 and 22 carbon atoms phosphated + mixture of alcohols of 20 and 22 carbon atoms (54/46)</td>

<td>D</td><td>C 20 and C22 alkylpolyglucoside mix + C20 and C22 alcohol mix (20/80)</td>

<td>AND</td><td>A mixture of phosphatized C 20 and C 22 alcohols</td>

<td>F</td><td>Mixture of alcohols of 20 and 22 carbon atoms phosphated + mixture of alcohols of 16 and 18 carbon atoms (50/50)</td>

<td>H</td><td>Stearic acid + PEG 100 stearate (67/33)</td>

C16 phosphate alcohol is marketed by the company GIVAUDAN-ROURE under the name Amphisol® A.

The mixtures of alcohols of 20 and 22 carbon atoms and of 16 and 18 carbon atoms are, respectively, 70/30 and 50/50 mixtures.

The mixture of alcohols of 20 and 22 carbon atoms is prepared under the conditions of Example 1 using 0.75 kg of mixture of alcohols of 20 and 22 carbon atoms and 0.22 kg of phosphoric anhydride.

EXAMPLE 2: Evidence of improved touch

Emulsions having the following composition are prepared.

Fat phase

Emulsifier

Cetearyl Octanoate%

Aqueous phase

Water qs 100%

Tromethamine qs pH = 5.5

Preservatives cs

The prepared emulsions are controlled by a sensory evaluation: the comfort criteria are scored from 0 to 5 by a jury of experts after being applied to the face. The following are evaluated: the greasy sensation (where 0 = not greasy and 5 = very greasy) and the presence of residue (where 0 = absence of residue and 5 = significant residue).

The results are presented in Table 2.

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TABLE 2

<td>Emulsifier</td><td>TO</td><td>B</td><td>C</td><td>D</td><td>AND</td><td>F</td>

<td>Sensory evaluation:</td><td> 3</td><td> 3</td><td> 0</td><td> 2</td><td></td><td> 3</td>

<td>- grease</td><td> 4</td><td> 2</td><td> 0</td><td> 1</td><td> -</td><td> 4</td>

<td>- residue</td><td></td><td></td><td></td><td></td><td></td><td></td>

The emulsifier C according to the invention is distinguished by its non-greasy feel as well as the absence of residue on the skin. Note that the emulsion including emulsifier E is not stable.

EXAMPLE 3: Evidence of improved water resistance

Emulsions having the following composition are prepared.

A Emulsifier 3%

Diisopropyl adipate 10%

Glycerin 7%

Ethylhexyl methoxycinnamate 7.50%

Octocrylene 10%

Butylmethoxydibenzoylmethane 2%

B Acrylamide / acryloyldimethyltaurate and isodecane and polysorbate 80 copolymer 1.20%

Cyclomethicone 5%

C Tetrasodium EDTA 0.20%

Xanthan gum 0.15%

Magnesium aluminum silicate 0.15%

Water qs 100%

D Preservative cs

Tromethamine qs pH = 5

Water resistance is determined in vivo in a group of volunteers according to the following protocol:

Phase 1

Determination of skin areas on the back: one area per emulsion tested + a control area on which no emulsion is applied.

Application of emulsions at a rate of 2 mg / cm².

UV irradiation on all the areas 15 minutes after the application of the emulsions (xenon lamp).

After a period of 16 to 24 hours after irradiation, visual reading of the minimum erythemal doses (DEM) in all the areas.

Calculation of the sun protection indexes of the tested products:

Product IP = DEM of the product zone / DEM of the witness zone

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Phase 2

Determination of new skin areas on the back: a tested emulsion area and a control area. Application of emulsions at a rate of 2 mg / cm².

Carrying out two baths of 20 minutes each, spaced 10 minutes apart.

UV irradiation on all the areas 15 minutes after the baths (xenon lamp).

Visual reading of the minimum erythemal doses in all the areas after bathing.

Calculation of the sun protection index after bathing:

Product IP = DEM of the product zone after bathing / DEM of the control zone after bathing Water resistance = Sun protection index after bathing (phase 2) / Sun protection index (phase 1) The prepared emulsions are controlled by sensory evaluation.

The results are presented in table 3

TABLE 3

<td>Emulsifier</td><td>Water resistance in%</td><td>Sensory evaluation: fat</td><td>Sensory evaluation: residue</td>

<td>TO</td><td> 18</td><td> 3</td><td> 4</td>

<td>B</td><td> 17</td><td> 3</td><td> 2</td>

<td>C</td><td> 35</td><td> 0</td><td> 0</td>

The emulsion according to the invention, which includes emulsifier C, exhibits significantly improved water resistance without, however, leaving a greasy feel or residue on the skin.

EXAMPLE 4: Evidence of foundation emulsion enhancement

Emulsions are prepared having the following composition:

Fat phase

Emulsifier 3%

Isononyl Isononanoate 10%

Triisostearyl Citrate 10%

Aqueous phase

Water qs 100%

Iron oxides 1.2%

Dimethicone PEG 7 phosphate 0.8%

Titanium oxide 12%

Talc 4%

Butylene glycol 4%

PEG 400 4%

Trishydroxyaminomethane cs pH 7

Polyacrylamide and isoparaffin of 13 and 14 carbon atoms and Laureth-7 1.5%

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Emulsions are controlled:

• by visual monitoring (macroscopic) of the stability of the emulsions with verification after three months of the appearance of the emulsions in the bottle: smooth or grainy appearance, glossy or matte appearance, monitoring of phase separation phenomena, separation of pigments on the surface of the emulsion or stratification of pigments with a heterogeneous visual effect. The optimal criteria are a brilliant, perfectly smooth and homogeneous emulsion without phase separation or separation or stratification of pigments and fillers. The rating is as follows: + if all the criteria are satisfactory; +/- if at least one of the criteria is unsatisfactory and 0 if none of the criteria is satisfactory.

• by monitoring the texture with the production of films calibrated at 120 pm on a plexiglass plate and verifying the absence of agglomerates of fillers and pigments. The qualification is the following: + if there are no grains 3 months after the manufacture of the emulsion; +/- if there are some grains; 0 if there are numerous grains.

• by an evaluation of the resistance or resistance of the emulsion on the face by a professional make-up artist 4 hours after application. The qualification is as follows: + if there is no migration of pigments and loads towards wrinkles and wrinkles; +/- if there is a moderate migration and 0 if there is a major migration.

• by means of a sensory evaluation: the comfort criteria are scored from 0 to 5 by a jury of experts after application to the face. The following are evaluated: the greasy sensation (with 0 = not greasy and 5 = very greasy), the sensation of freshness (with 0 = absence of freshness and 5 = important freshness) and the ease of extension or application on the face (being 0 = difficult to extend and 5 = easy to extend).

The results are presented in Table 4.

TABLE 4

<td>Emulsifier</td><td>TO</td><td>C</td><td>D</td><td>H</td>

<td>Visual control</td><td> +</td><td> +</td><td> +</td><td> +/-</td>

<td>Tracking the texture</td><td> +/-</td><td> +</td><td> +/-</td><td> +/-</td>

<td>Migration</td><td> +/-</td><td> +</td><td> 0</td><td> 0</td>

<td>Sensory evaluation:</td><td> 3</td><td> 2</td><td> 2</td><td> 2</td>

<td>- grease</td><td> 3</td><td> 4</td><td> 4</td><td> 3</td>

<td>- freshness</td><td> 3</td><td> 4</td><td> 5</td><td> 3</td>

<td>- residue</td><td></td><td></td><td></td><td></td>

Among the emulsifiers tested, emulsifier C according to the invention simultaneously provides a maximum of the criteria sought.