DE19849228A1 - Use of compositions containing vitamin E and chitosan - Google Patents

Abstract

Vitamin-containing compositions, containing (a) chitosan and/or chitosan derivatives and (b) tocopherols, are used to prepare agents for topical application.

Description

Field of the Invention

The invention relates to the use of vitamin-containing preparations containing chito sanen and tocopherols for the manufacture of compositions for topical use, in particular suns preservatives.

State of the art

It has long been known from the prior art that so-called free radicals on the human or animal organism have a harmful influence. Free oxygen radicals, So molecular oxygen with two unpaired electrons is, for example, under the influence formed by UV light and can begin damage to the skin in strong sunlight from mild sunburn to severe skin erythema. The is less known Free radical influence on DNA. Damage caused in this way leads to an incorrect reproduction of the genetic information. Cells that degenerate in this way become usually identified by highly specialized guardian proteins and by starting one Suicide program eliminated. However, the defect is found in the reproduction of the guardian proteins instead of and can no longer perform their function, there is an unchecked Degeneration of cells that can eventually lead to cancer.

In this regard, there has been no shortage of attempts to free radicals on the skin surface intercept before they develop their harmful effects. Enjoy special attention Radical scavengers of the type tocopherols, for example as a component of sunscreens to be applied to the skin. Abandonment of these toxicologically harmless substances, which occasionally To simplify the term vitamin E, it is to trap radicals and to be transferred in compounds with lower energy content and therefore reduced activity.  

The problem that arises in this context is the very slow absorption of Tocopherols through the skin. This leads to the use of relatively high doses of the radical scavenger must be ensured to ensure that an effective and as even as possible concentration on is present on the skin surface or in the uppermost skin layers. As a result, there is a lively interest in additives to tocopherols, with the help of which their absorption by Skin can improve. The object of the invention was therefore to prepare preparations of tocopherols which have these improved properties.

Description of the invention

The invention relates to the use of preparations containing vitamins

• (a) chitosans and / or chitosan derivatives and
• (b) tocopherols

for the preparation of agents for topical use, in particular sunscreens.

Surprisingly, it was found that the addition of chitosans, i.e. H. Chitosan various Molecular weights, chitosan salts or chitosan derivatives, the penetration of vitamin E, i.e. toco pherols accelerated significantly through the skin. In this way the effectiveness of Son protective agents can be increased significantly.

Chitosane

Chitosans are biopolymers and belong to the group of hydrocolloids. From a chemical point of view, these are partially deacetylated chitins of different molecular weights, which contain the following - idealized - monomer unit:

In contrast to most hydrocolloids, which are negatively charged in the range of biological pH values , chitosans are cationic biopolymers under these conditions. The positively charged Chitosans can and do interact with oppositely charged surfaces therefore in cosmetic hair and body care products as well as pharmaceutical preparations used (cf.Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A6, Weinheim, Verlag Chemie, 1986, pp. 231-332). Overviews on this topic are also available from B. Gesslein et al. in HAPPI 27, 57 (1990), O. Skaugrud in Drug Cosm. Ind. 148, 24 (1991) and E. Onsoyen et al. in Seifen-Öle-Fette-Wwachs 117, 633 (1991). To make the Chitosane is assumed to be from chitin, preferably the shell remains of crustaceans, which are considered cheap Raw materials are available in large quantities. The chitin is produced in a process that for the first time by Hackmann et al. has been described, usually first by adding bases deproteinized by adding mineral acids and finally by adding strong bases deacetylated, the molecular weights being distributed over a broad spectrum can. Appropriate methods are, for example, made from Makromol. Chem. 177, 3589 (1976) or French patent application FR-A 2701266 known. Such types are preferred used as in the German patent applications DE-A1 44 42 987 and DE-A1 195 37 001 (Henkel) and which have an average molecular weight of 50,000 to 25,000 or 800,000 to 1,200,000 daltons, a Brookfield viscosity (1% by weight in glycolic acid) below of 5000 mPa.s, a degree of deacetylation in the range from 80 to 88% and an ash content of have less than 0.3% by weight. In addition to the chitosans as typical cationic biopolymers come anionically or nonionically derivatized chitosans, such as. B. Carboxylation, succinylation or alkoxylation products in question, such as those in German patent DE-C2 37 13 099 (L'Oreal) and the German patent application DE-A1 196 04 180 (Henkel) can be described.

Tocopherols

Tocopherols are taken to mean chroman-6-oles (3,4-dihydro-2H-benzopyran-6-ole) substituted in the 2-position with a 4,8,12, -trimethyltridecyl radical. The plastoquinones, tocopherolquinones, ubiquinones, bovichinones, K vitamins and menaquinones (2-methyl-1,4-naphthoquinones) belong to the same group of bioquinones, ie to the polyprenylated 1,4-benzo or naphthoquinones. Particularly suitable are α-, β-, γ- and d-tocopherols which follow the general formula (I) (R = hydrogen or methyl), the ε-tocopherols of the general formula (II) which still have the original unsaturated prenyl side chain have, as well as the α-tocopherol quinones and hydroquinones of the general formula (III), in which the pyran ring system is open.

In addition to the tocopherols, there are also their derivatives, in particular esters with carboxylic acids, such as for example, tocopherol acetate or palmitate as additives. The operating conditions of the Components (a) and (b) can be 90:10 to 10:90, preferably 75:25 to 25:75 and in particular 60: 40 to 40: 60. The total concentration of the mixtures after oral intake should be in the Range from 0.001 to 10, preferably 0.01 to 1 and in particular 0.1 to 0.5 g / kg body weight lie. The content of the mixtures lies in preparations intended for topical application at 0.01 to 5, preferably at 0.1 to 3 and in particular at 0.5 to 1 wt .-% - based on the Medium.

Industrial applicability

In a preferred embodiment of the invention, the agents for topical application Are sunscreens which can be present as lotions, oils or creams. These can also as further auxiliaries and additives, mild surfactants, oil bodies, emulsifiers, superfatting agents, pearlescent waxes, stabilizers, consistency enhancers, thickeners, cation polymers, silicone compounds, biogenic agents, antidandruff agents, film formers, preservatives, hydrotropes, solubilizers, UV light protection filters, insect repellents, self-tanners, perfume oils, dyes and the like hold.

Typical examples of suitable mild, i.e. H. Surfactants that are particularly compatible with the skin are fatty alcohol poly glycol ether sulfates, monoglyceride sulfates, mono- and / or dialkyl sulfosuccinates, fatty acid isethionates,  Fatty acid sarcosinates, fatty acid taurides, fatty acid glutamates, ether carboxylic acids, alkyl oligoglucosides, Fatty acid glucamides, alkylamido betaines and / or protein fatty acid condensates, the latter. Preferably based on wheat proteins.

Guerbet alcohols based on fatty alcohols having 6 to 18, preferably 8 to 10 carbon atoms, esters of linear C ₆ -C ₂₂ fatty acids with linear C ₆ -C ₂₂ fatty alcohols, esters of branched C ₆ -C ₁₃ carboxylic acids are, for example, oil bodies with linear C ₆ -C ₂₂ fatty alcohols, esters of linear C ₆ -C ₂₂ fatty acids with branched alcohols, in particular 2-ethylhexanol, esters of linear and / or branched fatty acids with polyhydric alcohols (such as propylene glycol, dimer diol or trimer triol) and / or Guerbet alcohols, triglycerides based on C ₆ -C ₁₀ fatty acids, liquid mono- / di- / triglyceride mixtures based on C ₆ -C ₁₈ fatty acids, esters of C ₆ -C ₂₂ fatty alcohols and / or Guerbet alcohols with aromatic carboxylic acids, especially benzoic acid, vegetable oils, branched primary alcohols, substituted cyclohexanes, linear C ₆ -C ₂₂ fatty alcohol carbonates, Guerbet carbonates, esters of benzoic acid with linear and / or branched n C ₆ -C ₂₂ alcohols (e.g. B. Finsolv® TN), dialkyl ethers, ring opening products of epoxidized fatty acid esters with polyols, silicone oils and / or aliphatic or naphthenic hydrocarbons.

Examples of suitable emulsifiers are nonionic surfactants from at least one of the following groups:

• (1) Addition products of 2 to 30 moles of ethylene oxide and / or 0 to 5 moles of propylene oxide with linear Fatty alcohols with 8 to 22 carbon atoms, on fatty acids with 12 to 22 carbon atoms and on alkylphenols with 8 to 15 carbon atoms in the alkyl group;
• (2) C _12/18 fatty acid _monoesters and diesters of adducts of 1 to 30 moles of ethylene oxide with glycerol;
• (3) glycerol mono- and diesters and sorbitan mono- and diesters of saturated and unsaturated Fatty acids with 6 to 22 carbon atoms and their ethylene oxide addition products;
• (4) Alkyl mono- and oligoglycosides with 8 to 22 carbon atoms in the alkyl radical and their ethoxy analogs;
• (5) adducts of 15 to 60 moles of ethylene oxide with castor oil and / or hardened castor oil;
• (6) polyol and especially polyglycerol esters, such as. B. polyglycerol polyricinoleate, polyglycerol poly 12-hydroxystearate or polyglycerol dimerate. Mixtures of Verbin are also suitable doses from several of these classes of substances;
• (7) adducts of 2 to 15 moles of ethylene oxide with castor oil and / or hardened castor oil;
• (8) Partial esters based on linear, branched, unsaturated or saturated C _6/22 fatty acids, ricinoleic acid as well as 12-hydroxystearic acid and glycerin, polyglycerol, pentaerythritol, dipentaerythritol, sugar alcohols (e.g. sorbitol), alkyl glucosides (e.g. Methyl glucoside, butyl glucoside, lauryl glucoside) and polyglucosides (e.g. cellulose);
• (9) mono-, di- and trialkyl phosphates and mono-, di- and / or tri-PEG-alkyl phosphates;
• (10) wool wax alcohols;
• (11) polysiloxane-polyalkyl-polyether copolymers or corresponding derivatives;
• (12) Mixed esters of pentaerythritol, fatty acids, citric acid and fatty alcohol according to DE-PS 11 65 574 and / or mixed esters of fatty acids with 6 to 22 carbon atoms, methyl glucose and Polyols, preferably glycerin as well
• (13) Polyalkylene glycols.

The adducts of ethylene oxide and / or of propylene oxide with fatty alcohols, fatty acids, alkylphenols, glycerol mono- and diesters as well as sorbitan mono- and diesters of fatty acids or with castor oil are known, commercially available products. These are homologous mixtures, the middle of which Degree of alkoxylation corresponds to the ratio of the amounts of ethylene oxide and / or propylene oxide and substrate with which the addition reaction is carried out. C _12/18 fatty acid _monoesters and diesters of adducts of ethylene oxide with glycerol are known from DE-PS 20 24 051 as refatting agents for cosmetic preparations.

C _8/18 alkyl mono- and oligoglycosides, their preparation and their use are known from the prior art. They are produced in particular by reacting glucose or oligosaccharides with primary alcohols with 8 to 18 carbon atoms. Regarding the glycoside residue, both monoglycosides in which a cyclic sugar residue is glycosidically bonded to the fatty alcohol and oligomeric glycosides with a degree of oligomerization of up to about 8 are suitable. The degree of oligomerization is a statistical mean value which is based on a homolog distribution customary for such technical products.

Zwitterionic surfactants can also be used as emulsifiers. Zwitterionic surfactants are surface-active compounds that contain at least one quaternary ammonium group and at least one carboxylate and one sulfonate group in the molecule. Particularly suitable zwitterionic surfactants are the so-called betaines such as the N-alkyl-N, N-dimethylammonium glycinate, for example the coconut alkyldimethylammonium glycinate, N-acylamino propyl-N N-dimethylammonium glycinate, for example the coconut acylaminopropyldimethylammonium glycinate, and 2-alkyl-3-carboxyl hydroxyethylimidazolines each having 8 to 18 carbon atoms in the alkyl or acyl group and the cocoacylaminoethylhydroxyethylcarboxymethylglycinate. The fatty acid amide derivative known under the CTFA name Cocamidopropyl Betaine is particularly preferred. Suitable emulsifiers are ampholytic surfactants. Ampholytic surfactants are surface-active compounds which, in addition to a C _8/18 alkyl or acyl group, contain at least one free amino group and at least one -COOH or -SO ₃ H group in the molecule and are capable of forming internal salts . Examples of suitable ampholytic surfactants are N-alkylglycine, N-alkylpropionic acid, N-alkylaminobutyric acid, N-alkyliminodipropionic acid, N-hydroxyethyl-N-alkylamidopropylglycine, N-alkyltaurine, N-alkyl sarcosine, 2-alkyl aminopropionic acid and alkyl amino acetic acid each with about 8 up to 18 carbon atoms in the alkyl group. Particularly preferred ampholytic surfactants are the N-cocoalkylaminopropionate, the cocoacylaminoethylaminopropionate and the C _12/18 acyl sarcosine. In addition to the ampholytic emulsifiers, quaternary emulsifiers are also suitable, those of the esterquat type, preferably methyl-quaternized difatty acid triethanolamine ester salts, being particularly preferred.

Substances such as lanolin and lecithin as well as polyethoxylated or acylated lanolin and lecithin derivatives, polyol fatty acid esters, monoglycerides and Fatty acid alkanolamides are used, the latter at the same time as foam stabilizers to serve.

Pearlescent waxes, for example, are: alkylene glycol esters, especially ethylene glycol distearate; Fatty acid alkanolamides, especially coconut fatty acid diethanolamide; Partial glycerides, especially stea rinic acid monoglyceride; Esters of polyvalent, optionally hydroxy-substituted carboxylic acids Fatty alcohols with 6 to 22 carbon atoms, especially long-chain esters of tartaric acid; Fatty substances like for example fatty alcohols, fatty ketones, fatty aldehydes, fatty ethers and fatty carbonates, which in total min have at least 24 carbon atoms, especially lauron and distearyl ether; Fatty acids such as stea rinsic acid, hydroxystearic acid or behenic acid, ring opening products of olefin epoxides with 12 to 22 carbon atoms with fatty alcohols with 12 to 22 carbon atoms and / or polyols with 2 to 15 carbon atoms and 2 to 10 hydroxyl groups and mixtures thereof.

The main consistency agents are fatty alcohols with 12 to 22 and preferably 16 to 18 Carbon atoms and also partial glycerides into consideration. A combination of these is preferred Substances with alkyl oligoglucosides and / or fatty acid N-methylglucamides of the same chain length and / or Polyglycerol poly-12-hydroxystearates. Suitable thickeners are, for example, polysaccha ride, especially xanthan gum, guar guar, agar agar, alginates and tyloses, carboxymethyl cellulose and hydroxyethyl cellulose, as well as higher molecular weight polyethylene glycol mono and diesters of Fatty acids, polyacrylates (e.g. Carbopole® from Goodrich or Synthalene® from Sigma), polyacrylic amides, polyvinyl alcohol and polyvinyl pyrrolidone, surfactants such as ethoxylated fatty acid glycerides, esters of fatty acids with polyols such as pentaerythritol or trimethylolpropane, Fatty alcohol ethoxylates with a narrow homolog distribution or alkyl oligoglucosides as well as electrolytes like table salt and ammonium chloride.

Suitable cationic polymers are, for example, cationic cellulose derivatives, such as. Legs quaternized hydroxyethyl cellulose obtained from Amerchol under the name Polymer JR 400® Lich, cationic starch, copolymers of diallylammonium salts and acrylamides, quaternized Vinyl pyrrolidone / vinyl imidazole polymers, such as. B. Luviquat® (BASF), condensation products from Poly  glycols and amines, quaternized collagen polypeptides such as lauryldimonium hydroxy propyl hydrolyzed collagen (Lamequat®L / Grünau), quaternized wheat polypeptides, polyethyleneimine, cationic silicone polymers, such as. B. amidomethicones, copolymers of adipic acid and dimethyl aminohydroxypropyldiethylenetriamine (Cartaretine® / Sandoz), copolymers of acrylic acid with Dime thyldiallylammonium chloride (Merquat® 550 / Chemviron), polyaminopolyamides, such as. B. described in FR-A 2252840 and its crosslinked water-soluble polymers, cationic chitin derivatives such as for example quaternized chitosan, optionally microcrystalline, condensation products from dihaloalkylene, such as. B. dibromobutane with bisdialkylamines, such as. B. bis-dimethylamino-1,3- propane, cationic guar gum, such as B. Jaguar® CBS, Jaguar® C-17, Jaguar® C-16 from the company Celanese quaternized ammonium salt polymers such as. B. Mirapol® A-15, Mirapol® AD-1, Mirapol® AZ-1 from Miranol.

Suitable silicone compounds are, for example, dimethylpolysiloxanes, methylphenylpolysiloxanes, cyclic silicones as well as amino, fatty acid, alcohol, polyether, epoxy, fluorine, glycoside and / or alkyl modified silicone compounds that are both liquid and resinous at room temperature can lie. Typical examples of fats are glycerides. a. Beeswax, Carnauba wax, candelilla wax, montan wax, paraffin wax or micro waxes if necessary in Combination with hydrophilic waxes, e.g. B. cetylstearyl alcohol or partial glycerides in question. As Stabilizers can metal salts of fatty acids, such as. B. magnesium, aluminum and / or zinc stearate can be used. Examples of biogenic active ingredients are tocopherol and tocopherol acetate, tocopherol palmitate, ascorbic acid, deoxyribonucleic acid, retinol, bisabolol, allantoin, phy tantriol, panthenol, AHA acids, amino acids, ceramides, pseudoceramides, essential oils, plants to understand extracts and vitamin complexes. Climbazol, octopirox and zinc pyrethione can be used. Common film formers are, for example, chitosan, micro crystalline chitosan, quaternized chitosan, polyvinyl pyrrolidone, vinyl pyrrolidone-vinyl acetate copoly merisates, polymers of the acrylic acid series, quaternary cellulose derivatives, collagen, hyaluronic acid or their salts and similar compounds. Montmorillonites, as swelling agents for aqueous phases, Clay minerals, pemules and alkyl-modified carbopol types (Goodrich) are used.

UV light protection filters are organic substances that are able to absorb ultra violet rays and absorb the energy in the form of long-wave radiation, e.g. B. to release heat again. UVB filters can be unsoluble or water-soluble. As oil-soluble substances are z. B. To name:

• - 3-Benzylidene camphor and its derivatives, e.g. B. 3- (4-methylbenzylidene) camphor;
• - 4-aminobenzoic acid derivatives, preferably 4- (dimethylamino) benzoic acid 2-ethylhexyl ester, 4- 2-octyl (dimethylamino) benzoate and amyl 4- (dimethylamino) benzoate;  
• - Esters of cinnamic acid, preferably 2-ethylhexyl 4-methoxycinnamate, iso-4-methoxycinnamate pentyl ester, 2-cyano-3-phenyl-cinnamic acid 2-ethylhexyl ester (octocrylene);
• - Esters of salicylic acid, preferably salicylic acid 2-ethylhexyl ester, salicylic acid 4-isopropylbene methyl ester, salicylic acid homomethyl ester;
• - Derivatives of benzophenone, preferably 2-hydroxy4-methoxybenzophenone, 2-hydroxy-4-meth oxy-4'-methylbenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone;
• - Esters of benzalmalonic acid, preferably di-2-ethylhexyl 4-methoxybenzmalonate;
• - Triazine derivatives, such as. B. 2,4,6-Trianilino- (p-carbo-2'ethyl-1'-hexyloxy) -1,3,5-triazine and octyltriazone.
• Propane-1,3-diones, such as e.g. B. 1- (4-tert-butylphenyl) -3- (4'methoxyphenyl) propane-1,3-dione;

Possible water-soluble substances are:

• - 2-phenylbenzimidazole-5-sulfonic acid and its alkali, alkaline earth, ammonium, alkylammonium, Alkanolammonium and glucammonium salts;
• - Sulfonic acid derivatives of benzophenones, preferably 2-hydroxy4-methoxybenzophenone-5-sul fonic acid and its salts
• - Sulfonic acid derivatives of 3-benzylidene camphor, such as. B. 4- (2-Oxo-3-bornylidenemethyl) benzenesul fonic acid and 2-methyl-5- (2-oxo-3-bornylidene) sulfonic acid and their salts.

Derivatives of benzoylmethane, such as, for example, are particularly suitable as typical UV-A filters wise 1- (4'-tert-butylphenyl) -3- (4'-methoxyphenyl) propane-1,3-dione or 1-phenyl-3- (4'-isopropylphenyl) - propane-1,3-dione. The UV-A and UV-B filters can of course also be used in mixtures become. In addition to the soluble substances mentioned, insoluble pigments are also used for this purpose, namely finely dispersed metal oxides or salts, such as titanium dioxide, zinc oxide, Iron oxide, aluminum oxide, cerium oxide, zirconium oxide, silicates (talc), barium sulfate and zinc stearate. The Particles should have an average diameter of less than 100 nm, preferably between 5 and 50 nm and in particular between 15 and 30 nm. They can have a spherical shape have, however, such particles can be used that have an ellipsoid or in otherwise have a shape deviating from the spherical shape. In addition to the two The aforementioned groups of primary light stabilizers can also be secondary light stabilizers of the type of the antioxidants that interrupt the photochemical reaction chain, which is triggered when UV radiation penetrates the skin. Typical examples are superoxide Dismutase and ascorbic acid (vitamin C). Further suitable UV light protection filters are in the overview by P. Finkel in SÖFW-Journal 122, 543 (1996).

Hydrotropes such as ethanol, isopropyl alcohol or polyols can also be used to improve the flow behavior. Polyols that come into consideration here preferably have 2 to 15 carbon atoms and at least two hydroxyl groups. Typical examples are

• - glycerin;
• Alkylene glycols, such as, for example, ethylene glycol, diethylene glycol, propylene glycol, butylene glycol, Hexylene glycol and polyethylene glycols with an average molecular weight of 100 to 1000 daltons;
• - Technical oligoglycerol mixtures with a degree of self-condensation of 1.5 to 10 such as technical diglycerol mixtures with a diglycerol content of 40 to 50% by weight;
• Methyl compounds, such as in particular trimethylolethane, trimethylolpropane, trimethylolbutane, Pentaerythritol and dipentaerythritol;
• - Lower alkyl glucosides, especially those with 1 to 8 carbons in the alkyl radical, such as wise methyl and butyl glucoside;
• Sugar alcohols with 5 to 12 carbon atoms, such as sorbitol or mannitol,
• - Sugar with 5 to 12 carbon atoms, such as glucose or sucrose;
• - aminosugars, such as glucamine.

Suitable preservatives are, for example, phenoxyethanol, formaldehyde solution, para benzene, pentanediol or sorbic acid. As insect repellents there are N, N-diethyl-m-touluamid, 1,2- Pentanediol or Insect repellent 3535 in question, dihydroxyacetone is suitable as a self-tanner.

Perfume oils include extracts from flowers (lavender, roses, jasmine, neroli), stems and Leaves (geranium, patchouli, petitgrain), fruits (anise, coriander, caraway, juniper), fruit peel (bergamot, lemon, oranges), roots (mace, angelica, celery, cardamom, costus, lris, Calmus), woods (sandal, guaiac, cedar, rosewood), herbs and grasses (tarragon, lemon grass, sage, thyme), needles and twigs (spruce, fir, pine, mountain pine), resins and balsams (Galbanum, Elemi, Benzoe, Myrrh, Olibanum, Opoponax). Furthermore animal raw materials come in Question, such as musk, civet and castoreum. As a synthetic or semi-synthetic par Ambroxan, Eugenol, Isoeugenol, Citronellal, Hydroxycitronellal, Geraniol, Citronellol, Geranyl acetate, citral, ionone and methyl ionone.

As dyes, the substances suitable and approved for cosmetic purposes can be used be used, such as the dye in the publication "Cosmetic Colorants" Commission of the German Research Foundation, Verlag Chemie, Weinheim, 1984, pp. 81-106 are put together. These dyes are usually used in concentrations of 0.001 to 0.1 % By weight, based on the mixture as a whole.

The total proportion of auxiliaries and additives can be 1 to 50, preferably 5 to 40% by weight on the middle - amount. The agents can be produced by customary cold or hot processes respectively; the phase inversion temperature method is preferably used.  

Examples

To investigate whether chitosans release lipophilic tocopherols in the horny layer of the In an in-vitro study, a verum cream with 0.1% by weight chitosan was accelerated to the skin (Hydagen® CMF) and 1% by weight tocopherol (Cophenol® F1300) or tocopherol acetate (Cophernl® 1250) against a placebo cream with tocopherol or tocopherol acetate, but without chitosan tested. The investigation was carried out on the isolated perfused cattle udder model [cf. Kietzmann et al. in J. Pharm. Pharmacolog. 47, 22 (1993)].

To determine the release of the tocopherols, the "adhesive tape stripping" method was selected, which allows a differentiation between the upper part (stratum disjunctum) and the lower part (stratum compactum) of the horny layer during exposure. In simple terms, the test creams were applied to the skin (approx. 4 g / 100 cm ² ) and 10 test strips were attached. After an exposure time of 3 h, the adhesive strips were detached, dried and the detached amount of the stratum corneum (approx. 0.05 mg / cm ² ) was extracted. The amount of vitamin E in these extracts was determined by liquid chromatography and calculated in µg / cm ² stratum corneum. Each adhesive strip reflects the tocopherol or tocopherol acetate content in a different depth of the stratum corneum; the strip 1 stands for the top layer and the strip 10 for the deepest layer. The results are summarized in Table 1.

In the case of the release of tocopherol (Example 1, Comparative Example V1), it is found that the average amount of tocopherol released from the placebo cream, at 1.16 µg / cm ² stratum corneum (= 61%), is significantly lower than that Reformulation (1.88 µg / cm ² stratum corneum = 100%) was. Although the kinetics of tocopherol release were largely the same in both formulations, 10-fold amounts of tocopherol were found in the stratum disjunctum (strips 2 to 5).

In the case of the release of tocopherol acetate (example 2, comparative example V2), a still clear difference was found between the average amount of tocopherol acetate released from the placebo cream and the verum cream, namely 0.45 (21%) to 2.16 (100%) µg / cm ² stratum corneum. Placebo and verum formulations show a negative gradient of tocopherol acetate release over the depth of the stratum corneum; in the case of the verum cream, however, the tocopherol acetate content was on average twice as high as that of the placebo.

Table 1

Release of tocopherol or tocopherol acetate

Claims (7)

1. Use of preparations containing vitamins, containing

• (a) chitosans and / or chitosan derivatives and
• (b) tocopherols

for the preparation of agents for topical use. 2. Use according to claim 1, characterized in that chito as component (a) sane uses an average molecular weight in the range of 50,000 to 250,000 Show dalton. 3. Use according to claim 1, characterized in that chito as component (a) sane uses an average molecular weight in the range of 800,000 to 1,200,000 Show dalton. 4. Use according to claims 1 to 3, characterized in that as a component (b) Vitamin E is used. 5. Use according to claims 1 to 3, characterized in that one as a component (b) uses tocopherol acetate. 6. Use according to claims 1 to 5, characterized in that the compo nenten (a) and (b) in a weight ratio of 90:10 to 10:90. 7. Use according to claims 1 to 6, characterized in that the components ten (a) and (b) is used together with oil bodies, emulsifiers and / or UV light protection filters.