NL8502130A - EMULSIVE SYSTEM FOR WATER-IN-OIL TYPE EMULSIONS AND EMULSIONS CONTAINING SUCH A SYSTEM. - Google Patents

Description

* N.0. 33,348 χ

Emulsifying system for water-in-oil type emulsions as well as emulsions containing such a system.

The invention relates to a new emulsifying system, which is in the form of a mixture of an alkaline earth metal and / or metal lanolate and a sterol, and to the use of this emulsifying system for the preparation of emulsions of the water-in -oil-5 type for the cosmetic or pharmaceutical industry.

French patent 72.10843 has already proposed to use as a emulsifying system for "water-in-oil" type anulsions a mixture consisting of a) at least one of the lanolates of magnesium, calcium, lithium, zinc or aluminum and b) hydrogenated lanolin and / or lanolin alcohol.

According to this patent, the described emulsions are more economical because, among other things, they are richer in water and have good storage stability at temperatures much higher or lower than room temperature.

Cosmetically, however, these emulsions do not have all the desirable properties generally intended for creams intended for application to the face. However, these water-in-oil emulsions are not flexible and have a tendency to whiten the skin upon application.

On the other hand, the use of hydrogenated lanolin and / or lanolin alcohol presents difficulties not only because of the price of the starting materials, but also because of fluctuations in their quality, which are due to a peroxidation phenomena which lead to the formation of ( undesirable odors and up to color changes.

In order to give the emulsions according to French patent 72.10843 more flexibility and to overcome the drawbacks, various co-emulsifiers of lanolates have been investigated, in particular sterols such as cholesterol.

Although the emulsions obtained were smoother and more pleasant to use, they nevertheless proved to have less stability than the emulsions according to French patent 72.10843.

After numerous investigations of this emulsifying system, consisting of a lanolate and a sterol, it was found that the problem of the stability of the emulsions was not related to the nature of the co-emulsifying agent, ie the sterol, but to the lanolate itself, 6502 1-: 0% w 2 depending on the preparation method used.

According to French patent 72.10843, the lanolates are prepared by the following two methods: 1) or by a double decomposition, first preparing the sodium or potassium salt of lanolic acid and diluting it to present as an isotropic solution and then from this solution the desired salt of lanolic acid precipitates by adding a solution of an inorganic salt, for example a chloride, 2) or by direct action of the desired metal hydroxide on lanolic acid.

These two processes have in common that they are carried out in an aqueous medium, so that certain undesirable basic soaps which are difficult to remove are present.

Since the presence of basic soaps, which adversely affect the stability of the emulsions, when the lanolate is combined with a sterol, other processes for the preparation of the lanolates have been tried, in particular the process, which consists of the direct reacting the lanolic acid with a metal or alkaline earth metal acetate and removing the acetic acid formed by heating under reduced pressure.

Surprisingly, it has been found that when the lanolates prepared by the latter process are combined with a sterol, such as cholesterol, very stable water-in-oil emulsions are obtained, which have good spreading properties.

On the other hand, the lanolates obtained by this method have an improved fat phase solubility of the emulsions due to the total absence of basic soaps.

The invention therefore relates to a new industrial product, namely an emulsifying system for emulsions of the "water-in-oil" type, consisting of a metal and / or alkaline earth metal alkylate and a sterol, wherein this lanolate is obtained by direct action of lanolic acid on alkaline earth metal and / or metal acetate in anhydrous environment.

According to the invention, the metal and alkaline earth metal alkylates are preferably lanolates of calcium, magnesium, zinc, copper or aluminum.

The alkaline earth metal alkylates, in particular the magnesium anolate, make it possible to obtain excellent emulsions of the water-in-oil type, which emulsions are very stable and easily applicable due to good spreading properties.

8502130 4 κ 3

As has already been mentioned, the process for preparing the lanolates intended to be used together with sterol as a co-emulsifying agent is extremely important.

This process, which is easy to perform, consists of reacting lanolinic acid and an alkaline earth metal or metal acetate directly in anhydrous medium and removing the acetic acid formed by heating under reduced pressure, thereby allowing maximum shift of equilibrium are being brought.

The reaction is generally carried out under nitrogen at a temperature of 80-150 ° C for a period sufficient to remove the acetic acid formed during the reaction by distillation under reduced pressure.

The conversion yield is generally between 90 and 99%, based on the lanolic acid used as starting material.

If desired, the resulting lanolates can be purified later by adding an aromatic solvent, such as toluene, to the mixture and by removing azeotropic distillation at a temperature between 100 and 140 ° C, any residual traces of acetic acid.

According to a variant of this method, the conversion of the lanolinic acid and the alkaline earth metal or metal acetate can be carried out and terminated in the presence of a high-boiling, cosmetically and / or pharmaceutically acceptable oil, for example petroleum jelly.

After the reaction, lanolates are thus obtained as an oil solution, which may form part of the fat phase of water-in-oil type emulsions.

Sterols which can be used as co-emulsifying agents of the new emulsifying system according to the invention can in particular be mentioned cholesterol sterol and 3-sitosterol.

In the emulsifying system of the invention, the weight ratio of lanolate / sterol ranges from about 95/5 to 40/60, the preferred ratio being about 90/10.

According to a variant of the invention, the alkaline earth metal or metal anoleate can be combined with at least one alkaline earth metal or metal salt of another fatty acid, for example a stearate or an oleate of calcium, magnesium, zinc, copper or aluminum, the amount of of the alkaline earth metal or metal salt of this other fatty acid is generally not more than 25 weight percent, based on the weight of the alkaline earth metal or metal anoleate. According to this variant, the mixture of alkaline earth metal or metal anolate 8502 1 3 4 and of the alkaline earth metal or metal salt of another fatty acid is obtained according to the above-described method, but starting from a mixture of lanolic acid and the other fatty acid which it is desired to add in the selected amount.

The invention also relates to flexible water-in-oil emulsions containing a water phase, a fat phase and an above-defined emulsifying system.

These emulsions, which can form cosmetic or pharmaceutical carriers, have a viscosity between 8.0 and 8.5 Pa.s, that is, lower than the viscosity of the emulsions according to French patent 72.10843, which have a viscosity with a of the order of 10 to 11 Pa.s.

In these emulsions, the concentration of the emulsifying system according to the invention is generally 3-20% by weight, preferably 5-12% by weight, based on the total weight of the emulsion.

The weight ratio of the fat phase and the emulsifying agent is between 95/5 and 50/50, but this ratio is preferably about 90/10.

The products which form the fat phase of the emulsions can be mentioned: - hydrocarbon oils, for example paraffin oil, stearyl octanoate, perhydrosqualene and solutions of a microcrystalline wax in oils, - animal or vegetable oils, such as sweet almond oil, avocado -oil, calophylum oil, lanolin, castor oil, horse fat, lard, olive oil, jojoba oil, butter oil, hop oil, oil, - mineral oils, the boiling range of which is under atmospheric pressure between about 250 ° C and 410 ° C, 30 - saturated or not saturated esters such as alkyl myristates, for example, the isopropyl, butyl and cetyl myristates, hexadecyl stearate, ethyl or propyl palmitate, triglycerides of octanoic acid and decanoic acid and cetyl ricinoleate.

The fat phase can also contain silicone oils soluble in other oils, for example dimethylpolysiloxane, methylphenylsiloxane and the silicone glycol copolymer.

To promote oil retention, one may also use waxes, for example, carnabaw wax, candellila wax, beeswax, microcrystalline wax and ozokerite.

40 When the emulsions are intended for cosmetic application, they can be in the form of hydrating sun creams or moisturizing creams for the face, body or hands as well as in the form of moisturizing make-up or foundations. In this case, the concentration of the aqueous phase of the emulsion is generally 20-70% by weight, preferably 40-60% by weight, based on the total weight of the emulsion.

These preparations can also be in the form of moisturizing sun sticks or moisturizing sticks for the face and body, as well as in the form of lipstick or eye makeup. In this case, the concentration of the aqueous phase in the emulsion is generally 5-70% by weight, based on the total weight of the emulsion.

The cosmetic preparations can contain all ingredients which are generally used in cosmetics, in particular dyes, pigments, sunscreens, perfumes, preservatives such as p-hydroxymethyl benzoate or p-hydroxypropyl benzoate as well as co-emulsifying agents, for example, the company Goldschmidt under the designation "PROTEGIN W." product placed on the market.

The preparations may additionally contain certain active substances which serve not only to maintain the skin but also to improve its properties, in particular its elasticity.

As examples of these materials, particular mention may be made of wetting agents such as thiamorpholinone and its derivatives, vitamins, revitalizing agents, protein derivatives such as elastin and collagen, etc.

The emulsions according to the invention can also form a carrier for certain therapeutically active substances, the preparations being in the form of creams.

Preferred active substances for this type of carrier may in particular be mentioned: - anti-inflammatory agents 3 after corticosteroids such as hydrocortisone, difluprednate, β-methasone or dexamethasone, - antibiotics such as erythromycin, clindamycin or neomycin, - keratolytic agents, such as retinoic acid or benzoyl-35 peroxide, - anti-psoriasis agents, such as anthralin, its derivatives and etretinate, - vitamins and its derivatives, for example vitamin A palmitate, biotin or d-panthenol, 40 - fungicides, such as imidazole derivatives or toll naphthate and 8502130 6 - natural or synthetic sex hormones, such as progesterone or testosterone.

The process for preparing the water-in-oil emulsions consists of dissolving the lanolate in the fat phase at a temperature of about 100 ° C in a first stage and stirring vigorously and adding it in a second stage of the sterol at a temperature of about 80 ° C, after which it is cooled to a temperature of about 40 ° C and the aqueous phase is added with vigorous stirring, which is preferably brought to the same temperature, then the emulsion is cooled with stirring to room temperature. If desired, the emulsion can be crushed using a roller mill.

The method just described makes it possible in particular to obtain creams. To obtain sticks, water is preheated at 80 ° C and added to the uncooled mixture, then the emulsion obtained is poured into the molds suitable for making sticks at this temperature.

The following examples further illustrate the invention.

PREPARATION OF THE LANOLATES

Preparation of the Zinc Lanolate 20.7 g of lanolic acid (0.5 mol) are introduced into a suitable vessel equipped with an acetic acid removal apparatus by distillation under reduced pressure and a nitrogen supply.

The vessel is heated to a temperature of 80 ° C until the lanolic acid is melted and then 53.77 g of zinc acetate. 2H 2 O (0.245 mol) are added at once.

The mixture is then brought to a temperature of 120-125 ° C in order to remove the water and acetic acid formed by distillation. The device is then gradually brought under reduced pressure (1.99 kPa) and the temperature is gradually brought to 137 ° C.

After 35 minutes, a first distillate of acetic acid and water (37 g) is obtained, and then a second distillate (1.66 g) after 40 minutes at a temperature of about 130-135 ° C under a pressure of 1.99 kPa.

100 g of toluene are then added and an azeotropic distillation of residual traces of acetic acid is then carried out under atmospheric pressure and at a temperature of 120-130 ° C.

Thanks to the latter treatment, acetic acid can be removed up to an amount of 97.6%, based on the theoretical value.

The zinc lanolate (233.6 g) is obtained in a yield of 8502 H -5 7 9855 and has a total acidity of 2.075 meq / g (theoretical value 2.11 meq / g).

Preparation of the copper anolate

Into a suitable vessel equipped with a device for the removal of acetic acid by distillation under reduced pressure and a nitrogen supply, 221.7 g of lanolic acid (0.5 mol) is added, which is heated to 90 DEG C. under nitrogen. ° C until the entire amount of lanolic acid has melted.

Then 50 g (0.245 mol) of copper acetate monohydrate are added and the mixture is brought to a temperature between 117 and 125 ° C with stirring. After the distillation has been removed, the equipment is placed under reduced pressure and under a pressure of 1.99 kPa, the temperature is gradually raised to 135 ° C.

There is thus obtained a first distillate (33.7 g) of acetic acid and water and then a second distillate (1.15 g) after one hour under a pressure of 1.99 kPa at 135 ° C.

Thereafter, further purification appears to be no longer necessary, the copper lanolate obtained contains only traces of acetic acid remaining.

This gives 252 g of copper lanolate with a yield of 100%.

20 Preparation of the magnesium anolate

2444.2 g of lanolic acid (5.5 mol), which is brought to a temperature of about 90 ° C under nitrogen, are introduced into a 6 liter three-necked flask equipped with a device suitable for distillation under reduced pressure and a nitrogen supply. . After melting the lanolic acid, 578.2 g of magnesium acetate. 4 H 2 O (2.7 mol) are then added in one go and heating is continued to a temperature of about 108 ° C. At this temperature, the acetic acid and the water of hydration of the magnesium acetate begin to distill. The temperature of the reaction mixture is then gradually brought to 130 ° C, the acetic acid formed being distilled.

The temperature is maintained at 130 ° C for about two hours and after distillation is removed, the equipment is placed under reduced pressure to promote the removal of residual acetic acid.

After an hour at 130-135 ° C under a pressure of 1.99 kPa, a first distillate (461 g) is obtained. 2505 g of Vaseline oil are then added and heating at 130-135 ° C under reduced pressure (6.65 Pa) is continued for one hour and a second distillate (47 g) is obtained.

40 The magnesium lanolate, which is a 50 percent solution in $ 5 Λ O *% 7 Λ

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8 Vaseline oil can be used as such for the preparation of water-in-oil type emulsions.

COSMETIC PREPARATIONS 5 Example I: lipstick 50 wt.% Calcium lanolate in petrolatum oil 17.00 g cholesterol 3.00 g beeswax 8.00 g castor oil 10.00 g 10 petrolatum oil 12.00 g dyes (D and C orange number 17) 0.50 g dyes (D and C red 8) 0.50 g titanium dioxide 2.30 g water + p-hydroxymethyl benzoate (0.2 wt%) qsp 100.00 g 15

Example II: moisturizing stick for the body 50 wt.% Magnesium anolate in petrolatum oil 8.10 g cholesterol 0.90 g 20 stearyl octanoate 3.00 g petrolatum oil 12.00 g ozokerite, 8.00 g water + p -hydroxymethyl benzoate (0.2 wt%) qsp 100.00 g 25

Example III: Moisturizing stick for the face 50 wt.% Magnesium anolate in petrolatum oil 12.00 g cholesterol 8.00 g perhydrosqualene 5.00 g 30 ozokerite 15.00 g water + p-hydroxymethyl benzoate (0.2 wt. %) qsp 100.00 g 8502130 9

Example IV: hydrating treatment cream copper anolate 3.32 g cholesterol 0.35 g petroleum jelly 23.33 g sunflower oil 10.00 g lanolin 5.00 g water + p-hydroxymethyl benzoate (0.2 wt%) q.s.p. 100.00 g 10

Example V: moisturizing foundation zinc anolate 6.37 g cholesterol 2.25 g petrolatum 10.00 g 15 petrolatum oil 26.38 g iron oxide + titanium oxide 7.00 g water + p-hydroxymethyl benzoate (0.2% by weight) qsp 100.00 g 20 Example VI: moisturizing sun cream 50 wt% calcium anolate in petrolatum oil 6.65 g cholesterol 0.35 g petrolatum oil · 20.00 g silicone oil 10.00 g 25 sun filter "PARS0L 1789 "(butylmethoxydibenzoylmethane), marketed by GIVAUDAN 3.00 g water + p-hydroxymethyl benzoate (0.2 wt%) qsp 100.00 g 30 Example VII: colored moisturizing cream 50 wt.% Magnesium anolate in petrolatum oil 6.00 g β-sitosterol 4.00 g paraffin oil 20.00 g silicone oil 3.00 g 35 stearyl octanoate 5.00 g iron oxide + titanium oxide 3.00 g water + p-hydroxymethyl benzoate (0.2 wt%) qsp 100.00 g 3502130 V% 10 e

Example VIII: moisturizing cream for after sunbath 50 wt.% Magnesium anolate in vasein oil 17.00 g cholesterol 3.00 g 5 isopropyl myristate 10.00 g petrolatum oil 38.00 g beeswax 5.00 g lanoin 5.00 g D-panthenol 2.00 g 10 water + p-hydroxymethyl benzoate (0.2 wt%) qsp 100.00 g

Example IX: Moisturizing face cream 50 wt.% Magnesium anolate in Vaseline oil 5.70 g 15 cholesterol 0.15 g paraffin oil 23.15 g isopropyl palmitate 4.00 g stearyl octanoate 3.00 g sesame oil 4.00 g 20 water + p-hydroxymethyl benzoate (0.2 wt%) qsp 100.00 g

Example X; moisturizing, caring cream 50 wt.% magnesium! anolate in Vaseline oil 2.85 g 25 cholesterol 0.15 g Vaseline oil 4.00 g

Protegin W, sold by the company GOLDSCHMIDT 30.00 g water + p-hydroxymethyl benzoate (0.2% by weight) q.s.p. 100.00 g

85021SU

Claims (11)

An emulsifying system for emulsions of the water-in-oil type, characterized in that it consists of a metal or alkaline earth metal lanolate and a sterol, which lanolate is obtained by direct action of lanolic acid on a metal or alkaline earth metal acetate in anhydrous environment. System according to claim 1, characterized in that the metal or alkaline earth metal anolate is calcium, magnesium, zinc, copper and / or aluminum anolate. System according to claim 1 or 2, characterized in that the sterol is cholesterol and / or β-sitosterol. System according to one or more of the preceding claims, characterized in that the weight ratio of 1anolate / sterol is between 95/5 and 40/6 and preferably about 90/10. Water-in-oil type emulsion containing a water phase, a fat phase and an emulsifying system, characterized in that the emulsifying system is a system according to one or more of claims 1 to 4. Emulsion according to claim 5, characterized in that it has a viscosity of 8.0-8.5 Pa.s. Emulsion according to claim 5 or 6, characterized in that the concentration of the emulsifying system is between 3 and 20% by weight, preferably between 5 and 12% by weight, based on the total weight of the emulsion. Emulsion according to one or more of claims 5-7, characterized in that the weight ratio of the fat phase to the emulsifying system is between 95/5 and 50/50 and preferably about 90/10. 9. Emulsion according to one or more of claims 5-8, characterized in that it is in the form of a cream and contains the water phase in a concentration between 20 and 70% by weight, preferably between 40 and 60 % by weight, based on the total weight of the emulsion. Emulsion according to one or more of claims 5-8, characterized. that it is in the form of a stick and contains the water phase at a concentration between 5 and 70% by weight, based on the total weight of the emulsion. 11. Emulsion according to one or more of claims 5-10, characterized in that it contains at least one active ingredient with cosmetic and / or therapeutic action and one or more ingredients usual for cosmetic or therapeutic preparations. ** * r- -