AU1442392A

AU1442392A - Stable multiple emulsions

Info

Publication number: AU1442392A
Application number: AU14423/92A
Authority: AU
Inventors: Gerd Dahms; Sven H. Gohla; Rainer Kropke; Jens Nielsen
Original assignee: Beiersdorf AG
Current assignee: Beiersdorf AG
Priority date: 1991-04-13
Filing date: 1992-03-19
Publication date: 1992-11-17
Also published as: CA2106566A1; DE4131678A1; WO1992018227A2; ES2152226T3; MX9201632A; PT100374A; FI934503A; CZ215593A3; HU9302884D0; WO1992018227A3; FI934503A0; HUT65296A; DE59209873D1; JPH06506392A; EP0580620A1; ATE196999T1; EP0580620B1

Abstract

Stable multiple emulsions contain a mixture of emulsifiers consisting of (i) a first, hydrophobic emulsifier (emulsifier A) or several such emulsifiers mixed, having the following properties: it must be highly soluble in the oil phase of the emulsion at the manufacturing temperature of the emulsion; it may not be isotropically soluble in water below approximately 50 DEG ; it may be isotropically soluble in the water at temperatures between approximately 50 DEG and the manufacturing temperature of the emulsion; it must act primarily as a W/O emulsifier at temperatures between approximately 50 DEG and the manufacturing temperature of the emulsion; and (ii) a second, hydrophilic emulsifier (emulsifier B) or several such emulsifiers mixed, having the following properties: it must be isotropically soluble in water; its solubility at temperatures between approximately 50 DEG and the manufacturing temperature of the emulsion must be substantially stable.

Description

Beiersdorf Aktiengesellschaft Description Stable multiple emulsions The present invention relates to stable multiple 5 emulsions, to processes for their preparation, and to their use for cosmetic and medical purposes. Cosmetic skincare is mainly understood as meaning the enhancement or restoration of the natural function of the skin as a barrier against impacts from the environ 10 ment (for example pollution, chemicals, microorganisms) and against the loss of the body's own substances (for example water, natural fats, electrolytes). The disturbance of this function may result in increased resorption of toxic or allergenic substances or 15 attack [sic] of microorganisms and, as a consequence, toxic or allergic skin reactions. Another aim of skincare is to compensate for the loss of fats and water, by the skin, caused by daily washing. This is particularly important when the natural 20 regeneration capacity is insufficient. Skincare products are furthermore intended to protect against impacts from the environment, in particular sun and wind, and to delay ageing of the skin. Medical topical compositions generally contain 25 one or more pharmaceuticals in an effective concen tration. To differentiate clearly between cosmetic and medical use and the corresponding products, mention will be made, for simplicity's sake, of the legal situation of the Federal Republic of Germany (for example Kosmetik 30 verordnung [Cosmetics Act], Lebensmittel- und Arzneimittelgesetz [Foodstuffs and Pharmaceuticals Act]) . It is known that multiple emulsions can be distinguished, inter alia, by a particularly delicate texture. This property makes them outstandingly suitable 35 as a basis for both cosmetic and medical topical -2 preparations. Whereas cosmetics are only applied externally, all customary means of administration, for example oral formulations, are conceivable when emulsions are used for medical purposes. 5 A simple emulsion comprises, in the one phase, finely-disperse droplets of the second phase which are surrounded by a layer of emulsifier (water droplets in w/o emulsions, or lipid vesicles in o/w emulsions). In contrast, a multiple emulsion (second order) contains 10 more finely dispersed droplets of the first phase emul sified in said droplets. In these droplets, in turn, there may exist even more finely dispersed droplets (multiple emulsion of the third order), and so on. In the case of the simple emulsions, the techni 15 cal terms used are w/o-emulsions or o/w-emulsions (water in-oil or oil-in-water), and, in the case of the multiple emulsions, w/o/w-, o/w/o-, o/w/o/w-, w/o/w/o-emulsions, and so on. Multiple emulsions in which the particular 20 internal and external aqueous phases and internal and external oil phases are of a different nature (for example w/o/w'- and o/w/o'-emulsions) can be prepared by two-pot processes. Those emulsions in which the internal and external water or oil phases are not of a different 25 nature can be obtained by both one- and two-pot processes. The multiple emulsions of the second order are occasionally termed "bimultiple systems", those of the third order as "trimultiple systems", and so on 30 (W.Seifriz, "Studies in Emulsions", J.Phys.Chem., 29 (1925) 738 - 749). Processes for the preparation of multiple emulsions, are known per se to a person skilled in the art. For example, there are two-pot processes in which a 35 simple emulsion (for example a w/o-emulsion) is intro duced and converted into a multiple emulsion (in this case a w/o/w-emulsion) by adding a further phase (in this case an aqueous phase) with a suitable emulsifier (in this case an o/w-emulsifier).

-3 A second process comprises the conversion of emulsifier mixtures with an oil phase and an aqueous phase into a multiple w/o/w emulsion by a one-pot process. The emulsifiers are dissolved in the oil phase 5 and combined with the aqueous phase. The prerequisite for such a process is that the HLB values (HLB = Hydrophilic Lipophilic Balance) of the individual emulsifiers used differ substantially from each other. The formula 10 HLB = 20 (1 - S/A) provides the definition of the HLB value of polyol fatty acid esters. The formula HLB = E/5 15 in which S = saponification number of the ester, A = acid number of the acid recovered, E = ethylene oxide in the total molecule (%) applies to a group of emulsifiers whose hydrophilic moiety is composed of ethylene oxide units only. 20 Literature: "Kosmetik - Entwicklung, Herstellung und Anwendung kosmetischer Mittel" [Cosmetics Development, Preparation and Use of cosmetic preparations]; W.Umbach (editor), Georg Thieme Verlag 1988. 25 Hydrophilic emulsifiers (those having high HLB values) are generally o/w-emulsifiers. Accordingly, hydrophobic or lipophilic emulsifiers (those having low HLB values) are generally w/o-emulsifiers. Patent Specification US-A-4,931,210 describes a 30 process for the preparation of a w/o/w-emulsion, in which polyglycerol polyricinoleates are used as emulsifiers. Even though this shows that multiple emulsions are known per se and that simple processes for their preparation certainly exist, there has therefore been to 35 date a lack of those systems which are microscopically -4 stable. This is to be understood as meaning that the multiple emulsions of the prior art gradually undergo changes and result in a simple emulsion, that is to say that their storage stability with respect to multiplicity 5 is poor. This is particularly disadvantageous since the droplet size distribution of these conversion products is extremely inhomogeneous. Such conversion products are, at their best, aesthetically unsatisfactory or inelegant from the 10 cosmetic point of view. However, inhomogeneous size distribution of the droplets is frequently also combined with insufficient macroscopic stability, that is to say the stability to decomposition into separate phases. From this point of view, the conventional mul 15 tiple emulsions have also always left something to be desired. Unless otherwise indicated, the term "stability" in this Patent Application is therefore to be understood as meaning microscopic and macroscopic stability with 20 equal importance. It was therefore an object of the present inven tion to provide stable multiple emulsions and to eliminate the shortcomings of the preparations of the prior art. 25 It was furthermore an object of the invention to develop processes which allow multiple emulsions having the desired advantageous properties to be prepared in a simple and targeted manner. Surprisingly, it has now been shown, and this is 30 the achievement of the object, that stable multiple emulsions are obtained when an emulsifier mixture is used, comprising - a first, hydrophobic emulsifier (emulsifier A), or a mixture of several such emulsifiers, having 35 the following properties: - it must be very readily soluble in the oil phase of the emulsion at the preparation temperature of the emulsion - it must not be soluble in water to give an isotropic solution below approximately 500 - it must be soluble in water to give an isotropic solution in the temperature range between approximately 500 to the preparation 5 temperature of the emulsion and - it must act primarily as a w/o emulsifier in the temperature range between approximately 500 to the preparation temperature of the emulsion 10 - and a second, hydrophilic emulsifier (emulsifier B), or a mixture of several such emulsifiers, having the following properties: - it must be soluble in water to give an isotropic solution 15 - its solubility in the temperature range between approximately 500 to the preparation temperature of the emulsion must be essen tially stable. Such an emulsifier mixture can be used, in par 20 ticular, for preparing advantageous w/o/w-emulsions. The emulsifiers are advantageously chosen in such a way that the hydrophilic emulsifier uses the hydro phobic emulsifier at the phase inversion point, that is to say so that it acts as a wetting agent for the oily 25 phase and makes the formation of an in-situ multiple emulsion in a one-step process possible in the first place. It is furthermore advantageous if emulsifier A and emulsifier B can form a joint liquid-crystalline 30 phase which forms the interface of the emulsion droplets. Particularly advantageous emulsifier mixtures are those in which the hydrophobic emulsifier(s) A are soluble in an unpolar oil at the processing temperature, typically approximately 70 0 C, to an extent of more than 35 0.01 % by weight, advantageously more than 5.0 % by weight, if an unpolar oil is used, or in which the emulsifier(s) A are soluble in a polar oil to an extent of more than 0.02 % by weight, advantageously more than 20.0 % by weight, if a polar oil is used.

-6 The advantageous concentrations of emulsifier A in an unpolar oil may deviate from 5.0 % by weight in individual cases if the critical micelle formation concentration (CMC) in this oil deviates markedly from 5 the 5.0 % by weight which have been assumed as a guide value. A critical micelle formation concentration is not observed in polar oils. Examples of unpolar oils are mineral oils, that is to say those which are distinguished by a low content 10 of components having polar molecule groups. Examples of polar oils are vegetable oils (for example maize germ oil and wheat germ oil) or their synthetic and part-synthetic equivalents, and similar oils, that is to say those which are distinguished by a 15 higher content of components having polar molecule groups, for example ester or ether groups. This Patent Application distinguishes between isotropic solubility and anisotropic solubility, since the conventional terms of solubility can only be applied 20 with difficulty to surfactants. A substance is iso tropically soluble in another substance if it forms a true solution in this substance without the formation of micelles or other formation of aggregates which can be detected by means of light-microscopic methods. A 25 substance is anisotropically soluble in another substance if it is soluble in this substance, for example col loidally soluble, with the formation of micelles or the formation of other aggregates which can be detected by means of light-microscopic methods. 30 The hydrophobic emulsifiers A can be selected advantageously from the group comprising the glycerol ethers, for example

H

2 -C-O-R H-C-0-R 2

H

2 -C-0-R and polyglycerol ethers, where the radicals R'-" represent -7 H or a saturated or unsaturated organic radical, polyglycerol esters, for example

H

2 C-O-X-C-Ri

H-C-O-X-C-R

2

H

2 C 0

H

2 C H-C-0-X-C-R 3

H

2 C-0-X-C-R 4 (diglyceryl ester), -8

H

2 C-O-X-C-R1

H-C-O-X-C-R

2

H

2 C 0

H

2 C H-C-0-X-C-R 3

H

2 C 0 H 2 C H-C-0-X-C-R 4 H 2C-0-X-C-R5 (triglyceryl ester), where R- 5 , as is known to a person skilled in the art, independently of one another can represent H or a saturated or unsaturated organic radical, and X can 5 represent a single bond or a carbonyl radical, as well as methyl glucosides, sucrose esters, alkyl polyglycosides, sorbitan esters, sorbitol esters, iso sorbide esters. For the abovementioned classes of emul sifiers, see "Lexikon der Hilfsstoffe ffir Pharmazie, 10 Kosmetik und angrenzende Gebiete" [Dictionary of Auxiliaries in Pharmacology, Cosmetics and Related Fields] (H.P.Fiedler, Editio Cantor Aulendorf, Third Edition, 1989) for the corresponding entries, and, if appropriate, parallel references and cross-references. 15 What is disclosed under these entries in this dictionary -9 is included in the disclosure of the present Patent Application. It is advantageous to select representatives of the abovementioned classes of emulsifiers which, if they 5 are in ester form, contain mainly saturated fatty acid radicals or which, if they are in ether form, are derived from saturated fatty alcohols, that is to say, for example, this means for the glycerol ethers and poly glycerol ethers which have been listed above by way of 10 example that, if R1-s do not represent a hydrogen radical, they should represent saturated hydrocarbon radicals. The same applies to the other abovementioned classes of emulsifiers. Particularly advantageous is the use of those 15 hydrophobic emulsifiers which are solid at room temperature. The hydrophobic emulsifiers are particularly advantageously selected from the group comprising sorbitan oleate, sorbitan monostearate, Steareth-2, 20 glycerol monostearate, glyceryl oleate, polyglycerol-4-isostearate, PEG-7-hydrogenated castor oil, PEG-40-sorbitan monostearate, Laureth-4. Emulsifier(s) B can also expediently be selected from these substances, but it must be ensured that 25 emulsifier(s) B have the solubility properties demanded at the outset. The hydrophilic emulsifiers B are particularly advantageously selected from the group comprising Oleth-20, PEG-40-stearate, sucrose cocoate, 30 Trilaureth-4 -phosphate, Gluceth-20, PPG-20-methyl glucose ether, polyglycerol-3-stearate, polysorbate-120, sucrose laurate, Ceteareth 20. Stable multiple emulsions are also obtained according to the invention, and this is a further ad 35 vantageous embodiment of the present invention, when an emulsifier mixture is used in which the hydrophobic emulsifier A and the hydrophilic emulsifier B represent ethoxylated products. An emulsifier mixture comprising (a) at least one emulsifier of the general formula - 10 H H RI-Q-0-(C-C-Z-0-)m-H (emulsifier A), x Y in which R= C 10

.

3 0 -alkyl, Q = methylene or carbonyl, 5 X = H or methyl, Y = H or methyl, Z = methylene or a single bond and n = a number from 10 to 40, and 10 (b) at least one emulsifier of the general formula H H

R

2 -Q-O-(C-C-Z-O-) n-H (emulsifier B) x Y in which

R

2 = C, 3 ,-alkyl Q = methylene or carbonyl, 15 X = H or methyl, Y = H or methyl, Z = methylene or a single bond and m = a number from 1 to 400, with the proviso that the quotient n/m must be at 20 least 1.5, and (c) if appropriate, further emulsifiers, is therefore according to the invention. It is advantageous to select the emulsifier(s) A 25 from the group comprising the polyoxyethylene fatty alcohol ethers; in this case, these emulsifiers preferably have the general formula H H R -Q-0-(C-C-Z-0-) m-H (emulsifier A) x Y in which 30 R1 = C 1 0

-

30 -alkyl, - 11 Q = methylene, X = H, Y = H, Z = a single bond and 5 m = a number from 1 to 20. In this case, particularly preferred emulsi fiers A are those in which R1 = Cis-2s-alkyl, Q = methylene, 10 X = H, Y = H, Z = a single bond and m = a number from 1 to 10. However, emulsifier(s) A can also advantageously 15 be selected from the group comprising the polyoxyethylene fatty acid enters; in this case, these emulsifiers preferably have the general formula H H R I-Q-0-(C-C-Z-0-) M-H (emulsifier A) x Y in which 20 R = C 10

-

3 0 -alkyl, Q = carbonyl, X = H, Y = H, Z = a single bond and 25 m = a number from 1 to 20. In this case, particularly preferred emulsifiers A are those in which R1 = Cis-2s-alkyl, Q = carbonyl, 30 X = H, Y = H, Z = a single bond and m = a number from 1 to 10. Emulsifier(s) B are preferably selected from the 35 group comprising the polyoxyethylene fatty alcohol ethers; in this case, these emulsifiers preferably have - 12 the general formula H H

R

2 -Q-0-(C-C-Z-O-)n-H emulsifierr B) x Y in which = C 1 0

.

3 0 -alkyl, 5 Q = methylene, X = H, Y = H, Z = a single bond and n = a number from 10 to 400. 10 In this case, particularly preferred emulsi fiers B are those in which

R

2 = Cs 15 -2s-alkyl, Q = methylene, X = H, 15 Y =H, Z = a single bond and n = a number from 10 to 400. However, emulsifier(s) B can also advantageously be selected from the group comprising the polyoxyethylene 20 fatty acid esters; in this case, these emulsifiers preferably have the general formula H H

R

2 _Q-o-(C-C-Z-0-) n- (emulsifier B) x Y in which

R

2 = C 10

.

30 -alkyl, 25 Q = carbonyl, X = H, Y = H, Z = a single bond and m = a number from 10 to 400. 30 In this case, particularly preferred emulsi fiers B are those in which

R

2 = C s-2s-alkyl, - 13 Q = carbonyl, X = H, Y = H, Z = a single bond and 5 n = a number from 10 to 400. However, it may also be advantageous to mix those abovedescribed emulsifiers A which do not represent ethoxylated products with those emulsifiers B which represent ethoxylated products, if the physical proper 10 ties of the emulsifiers meet the requirements. Furthermore, it may also be advantageous to mix those abovedescribed emulsifiers B which do not represent ethoxylated products with those emulsifiers A which represent ethoxylated products if the physical properties 15 of the emulsifiers meet the requirements. Multiple emulsions in which the emulsifiers A and/or B are emulsifiers of the Steareth type are re garded as advantageous compositions according to the present invention. Steareth emulsifiers are available, 20 for example, under the tradename Brij* (Atlas-Chemie). The emulsifier system Steareth-2 (emulsifier A) and Steareth-21 (emulsifier B) has proved to be par ticularly advantageous. Steareth-2 is POE-(2) -stearyl alcohol, that is to 25 say, a stearyl alcohol which is ethoxylated with two ethylene oxide units. Steareth-21 is POE-(21)-stearyl alcohol, that is to say, a stearyl alcohol which is ethoxylated with 21 ethylene oxide units. 30 Stable multiple emulsions comprising the above designated emulsifiers which are described in greater detail in the claims and the customary cosmetic or medicinal components and, if appropriate, further emulsi fiers and/or auxiliaries and/or additives are therefore 35 according to the invention. The concentration of the total of emulsifiers A and B is preferably between 0.5 and 15.0 %, relative to the entire cosmetic or medicinal composition. The molar ratios of emulsifier A : emulsifier B -14 can advantageously be from 10 : 1 to 1 : 10, particularly advantageously 5 : 1 to 1 : 5, in particular 2 : 1 to 1 : 2, preferably 3 : 2 to 2 : 3, very particularly preferably 1.2 : 1 to 1 : 1.2. 5 If percentages are mentioned in this Patent Application, these are always to be understood as meaning percentages by weight unless specifically mentioned otherwise. It is advantageous to employ a mixture of 10 Steareth-2 : Steareth-21 in a ratio of 5 : 1 to 1 : 5. The most favourable total amount of this emulsifier system relative to the total composition is between 1 and 10 % in this embodiment. Very particularly advantageous are compositions 15 which contain, in addition to the compositions according to the invention, linoleic acid glycerides (trivial name for glycerol linoleates). It is also advantageous to use vegetable oils which contain large amounts of linoleic acid glycerides. 20 Surprisingly, the effect of the vegetable oils, or of the linoleic acid glycerides, consists in par ticular in the fact that they influence the microscopic structure of the multiple emulsions according to the invention in an advantageous manner, they lead to a 25 reduction in size of the droplets of the multiple emul sion and to an increased multiplicity of the systems. The linoleic acid glycerides, represented herein after in their Fischer projection, are to be understood as meaning the following: 30 The glycerol monolinoleates (glycerol 1-mono linoleate has two optical isomers): - 15 H 2 C-0-H H-C-O-L

H

2 C-0-H

H

2 C-0-L

H

2 0-L I I H-C-0-H and H-0-C-H

H

2 C-0-H

H

2 C-0-H The glycerol dilinoleates (the glycerol 1,2 dilinoleate has two optical isomers):

H

2 C-O-L H-C-0-H

H

2 C-O-L

H

2 C-O-L H 2 C-O-L H-C-C-L and L-O-C-H

H

2 C-0-H H 2 C-O-H The glycerol trilinoleate:

H

2 C-0-L H-C--L

H

2 C-O-L L in this context represents the cis,cis-9,12-octadeca 5 dienoyl radical. Whether oils are used in which the linoleic acid - 16 glycerides of various stoichiometric and isomeric forms exist as individual substances or in any desired mixture with each other is not of prime importance. The vegetable oils can preferably be selected 5 from the group comprising wheat germ oil, grape-pip oil, kukui oil, safflower oil and other oils which contain at least 5 % by weight of linoleic acid glycerides. Where the diameter of the multiple emulsions 10 without an addition of these oils is, typically, 20 pm, the diameter of the droplets can be reduced to 5 - 10 pm with such an addition. At the same time, the vegetable oils, or the linoleic acid glycerides, increase the yield of multiple 15 emulsion droplets. According to the invention, the multiple emul sions can contain 0.5 - 50 % by weight of vegetable oils, it is advantageous to use contents of 1.0 - 10.0 % by weight of these oils. 20 The compositions according to the invention can furthermore contain stearic acid and/or hydroxyoctacosanyl hydroxystearate, if this is desired. Surprisingly, an addition of this substance increases the stability of the multiple emulsions according to the 25 invention to high temperatures. It is preferred to use contents of 0.1 - 10 % by weight of stearic acid and/or hydroxyoctacosanyl hydroxystearate in the compositions according to the invention. Particularly advantageous are ratios by weight of stearic acid and/or hydroxy 30 octacosanyl hydroxystearate of 10 : 1 to 1 : 10. The simultaneous use of vegetable oils and stearic acid and/or hydroxyoctacosanyl hydroxystearate in the compositions according to the invention is particu larly advantageous. 35 The multiple emulsions according to the invention can be prepared from the starting materials by processes known per se, i.e. both by one-pot and by two-pot pro cesses. However, it has been demonstrated, and this is regarded as a further advantageous embodiment of the - 17 present invention, that particularly finely-textured and highly stable multiple emulsions are obtained, if not, as was hitherto customary, the total amount of emulsifiers is added to the fatty phase and the mixture is then 5 combined with the aqueous phase. Instead, the hydrophilic emulsifier(s) (emulsifier B) are incorporated into the aqueous phase and the hydrophobic emulsifier(s) (emulsifier A) are incorporated into the oil phase. Both phases are then combined with each other, advantageously 10 at a temperature at which the fatty phase is decidedly in liquid form. This process is a one-pot process. A process for the preparation of stable multiple emulsions, characterised in that the hydrophilic emul sifier is incorporated into the aqueous phase and the 15 hydrophobic emulsifier is incorporated into the oil phase and both phases are then combined with each other, advantageously at a temperature at which the fatty phase is decidedly in liquid form, is therefore according to the invention. 20 Advantageous auxiliaries and additives are, for example, consistency-imparting agents, fillers, perfume, colorants, emulsifiers, additional active substances such as vitamins or proteins, light stabilisers, stabilisers, antioxidants, preservatives, insect repellants, alcohol, 25 water, salts, proteolytically or keratolytically active substances, etc. The multiple emulsions according to the invention can advantageously be used in bodycare products such as, for example, creams or lotions for the face, hand creams, 30 hand lotions, body creams or body lotions, sun protection formulations, moisturisers, massage creams, nailcare products and the like. The examples which follow are intended to illustrate the present invention in greater detail 35 without intending to restrict the invention to these examples. Rather, a person skilled in the art is capable of varying the invention on the basis of his expert knowledge without departing from the basis of the invention.

- 18 Example 1 Massage cream I Steareth-2 3.00 % Steareth-21 3.00 % 5 Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 3.00 % Squalane 3.00 % 10 Isopropyl palmitate 1.80 % Acrylamide/sodium acrylate copolymer 0.18 % Demineralised water to 100.00 % Example 2 15 Massage cream II Steareth-2 5.00 % Steareth-21 3.00 % Petrolatum DAB [German Pharmacopoeia] 9 1.50 % 20 Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % Isopropyl palmitate 3.00 %

C

1 2 1.-alcohol benzoate 1.50 % Cetearyl alcohol 1.00 % 25 Hydroxyoctacosanyl hydroxystearate 0.40 % MgSO 4 0.60 % Cyclomethicone 2.50 % Preservative 0.50 % 30 Demineralised water to 100.00 % - 19 Example 3 Hand cream Steareth-2 4.50 % Steareth-21 1.50 % 5 Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 3.00 % Squalane 3.00 % 10 Isopropyl palmitate 1.80 % Acrylamide/sodium acrylate copolymer 0.18 % Demineralised water to 100.00 % Example 4 15 Sun cream Steareth-2 4.50 % Steareth-21 1.50 % Petrolatum DAB [German Pharmacopoeia] 9 4.20 % 20 Paraffin oil DAB [German Pharmacopoeia] 9 3.00 % Squalane 3.00 % Isopropyl palmitate 1.80 % Acrylamide/sodium acrylate 25 copolymer 0.18 % Eusolex 6300 2.00 % Demineralised water to 100.00 % - 20 Example 5 Moisturising cream I Sorbitan oleate 5.00 % Oleth-20 3.00 % 5 Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % Isopropyl palmitate 2.50 % 10 Cetearyl alcohol 1.00 % Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % Cyclomethicone 2.50 % 15 Demineralised water to 100.00 % Example 6 Moisturising cream II Sorbitan monostearate 5.00 % PEG-40-stearate 3.00 % 20 Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % Isopropyl palmitate 2.50 % 25 Cetearyl alcohol 1.00 % Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % Cyclomethicone 2.50 % 30 Safflower oil 4.00 % Demineralised water to 100.00 % - 21 Example 7 Moisturising cream III Steareth-2 5.00 % Sucrose cocoate 3.00 % 5 Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % Isopropyl palmitate 2.50 % 10 Cetearyl alcohol 1.00 % Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % Cyclomethicone 2.50 % 15 Grape-pip oil 4.50 % Demineralised water to 100.00 % Example 8 Moisturising cream IV Glycerol monostearate 5.00 % 20 Sucrose cocoate 3.00 % Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % 25 Isopropyl palmitate 2.50 % Cetearyl alcohol 1.00 % Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % 30 Cyclomethicone 2.50 % Kukui oil 6.00 % Demineralised water to 100.00 % - 22 Example 9 Moisturising cream V Glyceryl oleate 5.00 % Trilaureth-4-phosphate 3.00 % 5 Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % Isopropyl palmitate 2.50 % 10 Cetearyl alcohol 1.00 % Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % Cyclomethicone 2.50 % 15 Wheat germ oil 7.00 % Demineralised water to 100.00 % Example 10 Moisturising cream VI Polyglycerol-IV-isostearate 5.00 % 20 Gluceth-20 3.00 % Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % 25 Isopropyl palmitate 2.50 % Cetearyl alcohol 1.00 % Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % 30 Cyclomethicone 2.50 % Wheat germ oil 4.50 % Stearic acid 3.00 % Demineralised water up to 100.00 % Example 11 - 23 Moisturising cream VII PEG-7-hydrogenated castor oil 5.00 % PPG-20-methyl glucose ether 3.00 % Petrolatum DAB [German 5 Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % Isopropyl palmitate 2.50 % Cetearyl alcohol 1.00 % 10 Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % Cyclomethicone 2.50 % Kukui oil 5.30 % 15 Stearic acid 3.00 % Demineralised water up to 100.00 % Example 12 Moisturising cream IX PEG-40-sorbitan-monostearate 5.00 % 20 Polyglycerol-3-stearate 3.00 % Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % 25 Isopropyl palmitate 2.50 % Cetearyl alcohol 1.00 % Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % 30 Cyclomethicone 2.50 % Grape-pip oil 4.80 % Stearic acid 3.80 % Demineralised water to 100.00 % Example 13 - 24 Hand protection cream Laureth-4 5.00 % Polysorbate-120 3.00 % PEG-40 stearate 2.00 % 5 Petrolatum DAB [German Pharmacopoeia] 9 1.50 % Paraffin oil DAB [German Pharmacopoeia] 9 6.00 % Isopropyl palmitate 3.00 % 10 C.

1 -alcohol benzoate 1.50 % Cetearyl alcohol 1.00 % Hydroxyoctacosanyl hydroxystearate 0.40 % MgSO 4 0.60 % 15 Cyclomethicone 2.50 % Demineralised water to 100.00 % Example 14 Body lotion Glyceryl oleate 2.50 % 20 Sucrose laurate 1.00 % PEG-40 stearate 0.75 % Petrolatum DAB [German Pharmacopoeia] 9 1.50 % Paraffin oil DAB [German 25 Pharmacopoeia] 9 6.00 % Isopropyl palmitate 3.00 % Cn 1 -alcohol benzoate 1.50 % Cetearyl alcohol 1.00 % Hydroxyoctacosanyl 30 hydroxystearate 0.40 % MgSO 4 0.60 % Cyclomethicone 2.50 % Demineralised water to 100.00 % - 25 Example 15 Hand and nailcare emulsion Laureth-4 5.00 % Ceteareth 20 3.00 % 5 Petrolatum DAB [German Pharmacopoeia] 9 4.20 % Paraffin oil DAB [German Pharmacopoeia] 9 6.90 % PPG-15 stearyl ether 4.00 % 10 Cyclomethicone 2.50 % Preservative 0.50 % Demineralised water up to 100.00 % Example 16 Moisturising lotion 15 Laureth-4 5.00 % Ceteareth 20 3.00 % Petrolatum DAB [German Pharmacopoeia] 9 2.20 % Squalane 4.00 % 20 Isopropyl palmitate 2.50 % Ethylhexyl cocoate 4.00 % Cetearyl alcohol 1.00 % Hydroxyoctacosanyl hydroxystearate 0.80 % 25 MgSO 4 0.60 % Cyclomethicone 2.50 % Preservative 0.50 % Demineralised water to 100.00 % - 26 Example 17 Eyecare cream Steareth-2 3.75 % Steareth-21 2.25 % 5 Petrolatum DAB [German Pharmacopoeia] 9 1.20 % Squalane 4.00 % Ethylhexyl cocoate 4.00 % Cetearyl alcohol 0.50 % 10 Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % Cyclomethicone 2.50 % Preservative 0.50 % 15 Demineralised water to 100.00 % Example 18 Moisturising lotion Steareth-2 3.75 % Steareth-21 2.25 % 20 Petrolatum DAB [German Pharmacopoeia] 9 1.20 % Squalane 4.00 % Ethylhexyl cocoate 4.00 % Cetearyl alcohol 0.50 % 25 Shea butter 4.00 % Hydroxyoctacosanyl hydroxystearate 0.80 % MgSO 4 0.60 % Cyclomethicone 2.50 % 30 Preservative 0.50 % Demineralised water to 100.00 %

Claims

1. Stable multiple emulsions, containing an emul sifier mixture comprising - a first, hydrophobic emulsifier (emulsifier A), 5 or a mixture of several such emulsifiers, having the following properties: - it must be very readily soluble in the oil phase of the emulsion at the preparation temperature of the emulsion 10 - it must not be soluble in water to give an isotropic solution below approximately 50* - it must be soluble in water to give an isotropic solution in the temperature range between approximately 500 to the preparation 15 temperature of the emulsion and - it must act primarily as a w/o emulsifier in the temperature range between approximately 50* to the preparation temperature of the emulsion 20 - and a second, hydrophilic emulsifier (emulsifier B), or a mixture of several such emulsifiers, having the following properties: - it must be soluble in water to give an isotropic solution 25 - its solubility in the temperature range between approximately 50* to the preparation temperature of the emulsion must be essen tially stable.

2. Stable multiple emulsions according to Claim 1, 30 in which the emulsifier(s) A are soluble in an unpolar oil to an extent of more than 0.01 % by weight, in particular more than 5.0 % by weight, if an unpolar oil is used, or in which the emulsifier(s) A are soluble in a polar oil to an extent of more than 0.02 % by weight, 35 advantageously more than 20.0 % by weight, if a polar oil is used.

3. Stable multiple emulsions according to Claim 1 in which the hydrophobic emulsifier(s) A are selected from - 28 the group comprising the glycerol ethers, polyglycerol ethers, polyglycerol esters, methyl glucosides, sucrose esters, alkyl polyglycosides, sorbitan esters, sorbitol esters and isosorbide esters. 5

4. Stable multiple emulsions according to Claim 1 in which the hydrophilic emulsifier(s) B are selected from the group comprising glycerol ethers, polyglycerol ethers, polyglycerol esters, methyl glucosides, sucrose esters, alkyl polyglycosides, sorbitan esters, sorbitol 10 esters and isosorbide esters.

5. Stable multiple emulsions according to Claim 1, in which the hydrophobic emulsifier(s) A are selected from the group comprising sorbitan oleate, sorbitan monostearate, Steareth-2, 15 glycerol monostearate, glyceryl oleate, polyglycerol-4-isostearate, PEG-7-hydrogenated castor oil, PEG-40-sorbitan monostearate, Laureth-4, and the hydrophilic emulsifiers B from the group comprising 20 Oleth-20, PEG-40-stearate, sucrose cocoate, Trilaureth-4-phosphat, Gluceth-20, PPG-20-methyl glucose ether, polyglycerol-3-stearate, polysorbate-120, sucrose laurate, Ceteareth 20.

6. Stable multiple emulsions according to Claim 1, 25 containing (a) at least one hydrophobic emulsifier of the general formula H H R -Q-O-(C-C-Z-O-) m-H (emulsifier A), x Y in which 30 R= CIO- 30 -alkyl, Q = methylene or carbonyl, X = H or methyl, Y = H or methyl, Z = methylene or a single bond and 35 m = a number from 1 to 40, - 29 and (b) at least one hydrophilic emulsifier of the general formula H H R 2..-0-(C-C--0-)n -H (emulsifier B) x Y 5 in which R 2 = C 10 -s 3 -alkyl Q = methylene or carbonyl, X = H or methyl, Y = H or methyl, 10 Z = methylene or a single bond and n = a number from 10 to 400, with the proviso that the quotient n/m must be at least 1.5, and 15 (c) if appropriate, further emulsifiers, is therefore according to the invention.

7. Stable multiple emulsions according to Claim 1, characterised in that the emulsifier(s) A are selected from the group comprising the polyoxyethylene fatty 20 alcohol ethers, in particular those of the general formula H H R 1 -Q-0-(C-C-Z-0-) S-H. (emulsifier A) x Y in which R1 = Cis-2-alkyl, 25 Q = methylene, X = H, Y = H, Z = a single bond and m = a number from 1 to 10. 30

8. Stable multiple emulsions according to Claim 1, characterised in that the emulsifier(s) B are selected from the group comprising the polyoxyethylene fatty alcohol ethers, in particular those of the general - 30 formula H H -H (emulsifier B) x Y in which R2 = C 1 s-2s -alkyl, 5 Q = methylene, X = H, Y = H, Z = a single bond and n = a number from 10 to 400. 10

9. Stable multiple emulsions according to Claim 1, characterised in that the emulsifier(s) A are selected from the group comprising the polyoxyethylene fatty acid esters, in particular those of the general formula H H R -Q-O-(C-C-Z-0-) m-H (emulsifier A) x Y 15 in which R1 = C 15 -2s-alkyl, Q = carbonyl, X = H, Y = H, 20 Z = a single bond and m = a number from 1 to 10.

10. Stable multiple emulsions according to Claim 1, characterised in that the emulsifier(s) B are selected from the group comprising the polyoxyethylene fatty acid 25 esters, in particular those of the general formula H H R 2 -Q-O-(C-C-Z-O-) -H emulsifierr B) x Y in which R 2 = Cis-2s-alkyl, Q = carbonyl, 30 X = H, Y = H, - 31 Z = a single bond and n = a number from 10 to 400.

11. Stable multiple emulsions according to Claim 1, characterised in that the concentration of the total of 5 emulsifiers A and B is between 0.5 and 15.0 %, relative to the entire cosmetic or medicinal composition, and the molar ratios of emulsifier A : emulsifier B are from 10 1 to 1 : 10, particularly advantageously 5 : 1 to 1 : 5, in particular 2 : 1 to 1 : 2, particularly 10 favourably 1.2 : 1 to 1 : 1.2.

12. Stable multiple emulsions according to Claim 1, characterised in that Steareth 2 is selected as emul sifier A and Steareth 21 as emulsifier B, where a ratio of emulsifier A : emulsifier B of 5 : 1 to 1 : 5 is 15 chosen and the total amount of this emulsifier system relative to the total composition is between 1 and 10 %.

13. Stable multiple emulsions according to Claim 1, characterised in that they contain vegetable oils con taining large amounts of linoleic acid glyceride, in 20 particular wheat germ oil, grape-pip oil, kukui oil, safflower oil, and other oils which contain at least 5 % by weight of linoleic acid glycerides, where the emul sions preferably contain 0.1 - 50 % by weight of such oils or mixtures thereof relative to the total weight of 25 the composition.

14. Stable multiple emulsions according to Claim 1, characterised in that they contain stearic acid and/or hydroxyoctacosanyl hydroxystearate to an extent of 0.1 10 % by weight, in particular when the ratios by weight 30 of stearic acid and/or hydroxyoctacosanyl hydroxystearate to each other are 10 : 1 to 1 : 10.

15. Process for the preparation of stable multiple emulsions according to one of Claims 1 - 14, characterised in that the hydrophilic emulsifier(s) 35 (emulsifier B) are incorporated into the aqueous phase and the hydrophobic emulsifier(s) (emulsifier A) are incorporated into the oil phase, and the two phases are then combined with each other.