DE19602902A1 - Oil-based soap gel preparation - Google Patents

Abstract

The invention concerns a soap gel preparation for the use of cosmetic or pharmaceutical active substances, in particular in stick form, containing between 5 and 15 wt % fatty acids in the form of their alkali soaps, between 20 and 50 wt % of a water-soluble polyol, and between 30 and 70 wt % water, said preparation also comprising a portion of between 1 and 10 wt % of a water-insoluble oil in the form of an emulsion with a droplet size of less than 500 nm. The oil is transformed into a transparent microemulsion or an opalescent PIT emulsion and thus incorporated into the molten soap gel stick mass. Oils particularly suitable for this purpose are hydrocarbon oils, dialkylether with between 14 and 36 carbon atoms or mixtures of these substances with a fatty acid ester.

Description

The invention relates to a shaped preparation for use cosmetic and pharmaceutical pharmaceutical active ingredients, in particular in stick form, based on a soap gel, wel ches has a good dimensional stability and a water-insoluble, homogeneous incorporated Contains cosmetic oil and is largely free of lower alcohols.

Soap gels are used as carriers for topical cosmetic and pharmaceutical Active ingredients have been known for a long time. Sodium stearate gels are usually used as soaps in aqueous lower alcohols and glycols used. In recent years, attempts have been made to to reduce the content of lower alcohols or entirely by glycols and polyols replace. In addition, such pencils are tried to soften or moisturize the skin Incorporate components. This leads to the well-known water-insoluble oil components for inhomogeneity and separation. So you always have water soluble or water-dispersible emulsions used, e.g. B. according to EP-A 450 597 Alkylene oxide adducts with fatty alcohols. However, these products do not have sufficient cosmetic and skin care effects.

The stable incorporation of fragrance oils can also increase the transparency of the soap gels affect. EP-A 499 304 therefore used very specific fragrances been proposed. A way has now been found to be water-insoluble Integrate oils in considerable quantities in a stable and homogeneous manner in soap gel preparations.  

The invention therefore relates to a soap gel preparation for the topical use of cosmetic and pharmaceutical active ingredients, in particular in stick form, with a content of
5-15% by weight of fatty acids with 14-22 carbon atoms in the form of their alkali soap
20-50 wt .-% of a polyol with 2-6 C atoms and 2-6 hydroxyl groups
30-70 wt .-% water, characterized in that
1-10% by weight of a water-insoluble oil in the form of an emulsion with a drop size below 500 nm.

The conversion of water-insoluble oils into finely divided emulsions, e.g. B. in micro emulsions with drop sizes below 100 nm or in opalescent so-called PIT Emulsions with particle sizes from 100 to 300 nm according to the phase inversion process are state of the art. So z. B. from Progr. Colloid & Polymer Sci 73 (1987), 37-47 known how to make extremely fine oil-in-water emulsions using a combination Manufacture non-ionic emulsifiers and co-emulsifiers from hydrocarbon oils can. In DE-A 38 13 193 an emulsifier system is proposed, which the production such emulsions also with polar oils of the fatty acid ester type. Such PIT emulsions mostly contain emulsion droplets below 300 in size nm, however, proportions up to 10% by weight of the oil component in a droplet size from 300 to 500 nm. One method of making microemulsions are e.g. B. from DE-A 44 11 557 and DE-A 44 17 476 known.

All water-insoluble, skin-compatible oils and are suitable as oil components Fat substances and their mixtures with solid paraffins and waxes. The melting point however, any mixtures with solid paraffins and waxes used should if possible below the phase inversion range of the emulsion and preferably below of 40 ° C.

Suitable oil components which are compatible with the skin are preferably still Koh at 20 ° C. hydrogen, e.g. B. paraffin oils and synthetic hydrocarbons such. B. 1,3-Di- (2-  ethyl-hexyl) -cyclohexane (Cetiol®S). Another particularly suitable oil component are the di-n-alkyl ethers such. B. di-n-octyl ether, di (2-ethylhexyl) ether, lauryl methyl ether or octyl butyl ether.

In a preferred embodiment, there are soap gel preparations according to the invention as a water-insoluble oil, hydrocarbon oils, dialkyl ethers with 14-36 carbon atoms or Mixtures of these components with a fatty acid ester e.g. B. with a Capryl- / Ca contain pric acid triglyceride.

A particularly diverse group of cosmetic oil components is that of fatty acid and fatty alcohol esters, e.g. B. isopropyl myristate, n-butyl stearate, 2-ethylhexyl caprylate, cetylo leat, glycerol tricaprylate, coconut alcohol (C₁₂-C₁₈) caprylate / caprinate and others. Ge Also suitable are naturally occurring ester oils such as B. jojoba oil or liquid vegetable che triglyceride oils such. B. olive oil, sunflower oil, soybean oil, rapeseed oil, almond oil, the rivers share of coconut oil or beef tallow and synthetic triglceride oils.

Suitable dicarboxylic acid esters are e.g. B. di-n-butyl adipate, di-n-butyl sebacate, di- (2-ethyl hexyl) adipate, di (2-hexyldecyl) succinate and diisotridecyl acelaate. Suitable diol esters (III) are e.g. B. ethylene glycol dioleate, ethylene glycol di-isotridecanoate, propylene glycol di- (2-ethylhexanoate), propylene glycol di-isostearate, propylene glycol di-pelargonate, butanediol di-isostearate and neopentyl glycol di-caprylate.

In a mixture with these liquid oil components, smaller quantities can also be half solid and solid paraffins and waxes as well as solid triglyceride fats can be used.

As emulsifiers, the PIT emulsions contain a combination of a hydrophilic, nonionic emulsifier with an HLB value of preferably 10-15 and a lipophi len co-emulsifier. The HLB value should be understood to mean a quantity that consists of the structure of the emulsifier can be calculated according to

where L is the weight fraction (in%) of the lipophilic groups, e.g. B. the fatty alkyl or fet is tacyl groups in the emulsifier.

The hydrophilic emulsifiers are preferably ethylene oxide adducts on fatty alcohols with 16-22 carbon atoms or on partial esters of polyols with 3-6 carbon atoms and fatty acids with 14-22 carbon atoms. However, ethylene oxide adducts on fatty acids, on alkyl glucosides, on methyl glucoside fatty acid esters, on fatty acid alkanolamides, on fatty acid glucamides and other fatty substances with ethoxylatable substituents are also suitable. Particularly preferred as hydrophilic emulsifiers are alkyl polyglycosides of the formula RO- (Z) _x , in which R is a C₈-C₂₂-alkyl or alkenyl radical, Z is a monosaccharide, in particular glucose, and x whose degree of oligomerization is a number from 1 to 5, in particular of 1.2 to 1.4.

The lipophilic co-emulsifiers are preferably saturated fatty alcohols with 16-22 C-atoms to partial esters of polyols with 3-6 C-atoms with saturated Fatty acids with 14-22 carbon atoms to free fatty acids with 16-22 carbon atoms to glycol monofatty acid esters, to fatty acid alkanolamides from C₁₂-C₁₈ fatty acids with mono- or Dialkanolamines with 2-4 C atoms in the alkanol group or around glycerol mono fatty alcohol ether.

Suitable as fatty acids for the preparation of the soap gel preparations according to the invention z. B. palmitic acid, stearic acid, arachic acid, behenic acid or technical mixtures, which mainly consist of such fatty acids, e.g. B. hardened palm oil fatty acid or ge hardened tallow fatty acid. Stearic acid is preferably used. It can be very beneficial be, to increase the abrasion on the skin a part of the saturated, linear Fatty acids by branched chain fatty acids such as. B. 2-hexyldecanoic acid, 2-octyl to replace dodecanoic acid or isostearic acid. With such an addition to ver branched chain fatty acids is achieved that the soap gel preparations in temperature  range below 35 ° C have good strength, but in contact with the skin immediately melt and become slippery, so that a thin film of the preparation is easy spread on the skin.

The fatty acids are wholly or predominantly present as alkali salts (alkali soaps), preferably as sodium soap. Other neutralizing agents, e.g. B. triethanolamine, ver be applied. A small amount of free, unsaponified fatty acid, approximately in an amount from 0.01 to 0.5% by weight of the preparation, but is not disadvantageous.

As polyols with 2-6 carbon atoms and 2-6 hydroxyl groups such. B. ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 1,4-buty lenglycol, glycerin, erythritol, pentaerythritol, trimethylolpropane, sorbitol, methyl glucoside, Cyclohexanetriol, inositol can be used. Propylene glycols and Gly are preferred cerin alone or mixtures of these polyols with sorbitol and or butylene glycol. These polyols are preferably in a total amount of 20-50 wt .-% of the soap gel preparation ent hold. These polyols can also be partially replaced by polyethylene glycols.

The soap gel preparations according to the invention are preferably free of lower Al alcohol. However, it is optionally possible to use up to 10% by weight of lower alcohols e.g. B. ethanol or isopropanol instead of the polyols mentioned.

The soap gel preparations according to the invention are used topically for kos active pharmaceutical and pharmaceutical ingredients. Such active substances are, depending on the for the Dosage incorporated into the soap gel preparation for special applications tet. As cosmetic active ingredients such. B. antimicrobial, deodorant, skin moist antiperspirant, depilatory, coloring and fragrant substances as well as cosmetic Look at oils. As pharmacological agents such. B. antibiotics, corticosteroids, To understand local anesthetics, as well as other active substances that fight against skin diseases be turned. The amount of cosmetic or pharmaceutical active ingredients is in usually in the order of 0.1-5% by weight of the preparation, preferably in egg range from 0.1-1% by weight of the preparation.  

A particularly preferred field of application for the soap gel according to the invention Preparations is that of deodorant sticks. In such products are according to the invention contain deodorant substances as cosmetic active ingredients. Suitable deodorant Active ingredients are e.g. B. antimicrobial substances such. B. 2,4,4'-trichloro-2'-hydroxydiphenyl ether (Irgasan DP300), chlorhexidine digluconate or phenoxyethanol, deodorant, antimicrobial essential oils, farnesol, lipase inhibiting substances such as B. triethyl citrate, astringent substances such as B. sodium aluminum chlorohydroxy lactate and others known body deodorants or antiperspirants.

In a preferred embodiment, therefore, an antimicrobial or esterase inhibitor Deodorant active or an astringent antiperspirant active in one amount of 0.1-10% by weight in the soap gel preparation according to the invention.

In addition to the active substances mentioned, the soap gel preparations according to the invention can contain other aids to improve the appearance and storage stability are useful. Such tools are e.g. B. complexing agents, antioxidants, preserves agents, fragrances, colorants, opacifiers, pearlescent pigments, water-soluble Salts such as B. NaCl or finely divided, fumed silica.

The preparation of the soap gel preparations according to the invention is advantageously carried out in the Way carried out that one polyols, water and fatty acid mixtures in one container mixes while heating to approx. 50-90 ° C, this mixture forms the alkali hydroxide add a concentrated aqueous solution and agitate the mass until saponification the fatty acids are complete to form a clear solution. Then they can Active ingredients, auxiliaries and fine-particle emulsion of water-insoluble oil during the cooling are mixed in successively. Finally, the mass at one Temperature above the gelation temperature in a mold, e.g. B. in a pen sleeve, ge poured and allowed to cool there to a temperature at which the mass to form stable len gel froze.

Another subject of the patent is therefore the method for producing the Invention measure soap gel preparation, which consists in adding the water-insoluble oil known processes in a transparent microemulsion or in an opalescent PIT  Transfer emulsion with a particle size below 300 nm and this emulsion in the ge mixes melted soap gel stick mass and then solidifies the mass.

The following examples are intended to explain the subject of the invention in more detail:  

Examples Preparation of the PIT emulsion

3 parts by weight of 1,3-di- (2-ethylhexyl) cyclohexane (Cetiol®S)
1 part by weight of C₈ / C₁₀ fatty acid triglyceride (Myritol®318)
1.2 parts by weight of an emulsifier mixture consisting of
40% by weight cetyl / stearyl alcohol + 20 mol EO
37.5% by weight glycerol monostearate
7.5% by weight cetyl stearyl alcohol + 12 mol EO
7.5% by weight cetyl stearyl alcohol
7.5% by weight cetyl palmitate
were with
6 parts by weight of water are heated to a temperature of 95 ° C. and converted at this temperature into a finely divided emulsion which, after cooling to room temperature, has a slightly cloudy to opalescent appearance.

Manufacture of soap gel pens

6 parts by weight of stearic acid
10 parts by weight of 1,2-propylene glycol and
20 parts by weight of glycerin
50 parts by weight of water
were mixed and heated to 70 ° C. To this mixture
2 parts by weight of NaOH solution (45%)
added in portions, the mixture becoming homogeneous with hydrolysis.

Then were
0.2 parts by weight of Irgasan®DP500 (2,4,4'-trichloro-2'-hydroxydiphenyl ether) and
1 part by weight of perfume oil mixed in. Finally were
11 parts by weight of the previously prepared PIT emulsion, which had a temperature of 70 ° C, mixed. Then the mass was poured into pin sleeves and cooled to + 20 ° C.

Thereby, stable, homogeneous soap gel pens with a nourishing cosme content were created table oils.

Comparison test

If instead of the PIT emulsion, 10 parts by weight of a mixture of 6 parts by weight Glycerin, 3 parts by weight of emulsifier (cetylstearyl alcohol + 30 mol EO) and 1% by weight Table salt was added, a dimensionally stable, homogeneous stick was also obtained. Trying to add 2 parts by weight of one of the oil components or a mixture Adding the oil components (Cetiol S and / or Myritol 318), however, led to unan yearning, inhomogeneous masses.

Claims (5)

1. soap gel preparation for the topical application of cosmetic and pharmaceutical active ingredients, in particular in stick form, with a content of
5-15% by weight of fatty acids with 14-22 carbon atoms in the form of their alkali soap
20-50 wt .-% of a polyol with 2-6 C atoms and 2-6 hydroxyl groups
30-70 wt .-% water, characterized in that
1-10% by weight of a water-insoluble oil in the form of an emulsion with a droplet size below 500 nm
are included. 2. soap gel preparation according to claim 1, characterized in that a antimicrobial or lipase-inhibiting deodorant active ingredient or Antiperspirant active ingredient is contained in an amount of 0.1 to 10 wt .-%. 3. soap gel preparation according to claim 1 or 2, characterized in that as Polyols glycerin and / or propylene glycol or mixtures of these substances with sorbitol and / or 1,4-butylene glycol are included. 4. soap gel preparation according to claim 1 to 3, characterized in that as water-insoluble oil a hydrocarbon oil, a dialkyl ether with 14-36 C atoms or a mixture of these components with a fatty acid ester is contained. 5. A method for producing a soap gel preparation according to claim 1 to 4, characterized in that the water-insoluble oil according to known Ver drive into a transparent microemulsion or into an opalescent PIT emul sion with a particle size below 500 nm transferred and the emulsion in the ge mixes melted soap gel stick mass and then solidifies the mass.