Patent Application
20160067158
The present invention relates to agents for the preparation of highly concentrated formulations comprising large amounts of UV filters, a process for the preparation of sunscreen final formulations based on such agents and the use of such agents for the preparation of cosmetic formulations having extremely high sun protection factors (SPF up to 50+).
From the dermatological aspect, in addition to the care effect for the skin sunscreen formulations above all should reduce or as far as possible prevent the adverse effects of solar radiation. For this, sunscreen formulations comprise UV filters which via their activity, amount and combination determine the UV protections, usually expressed as the SPF factor.
For the manufacturer of such sunscreen formulations it is important for the UV filters to be present in a form which has a shelf life, which can be converted into their own, defined sunscreen final formulations easily and as far as possible at room temperature. By simple blending the manufacturer would like to obtain an O/W care emulsion of which the SPF factor can be determined according to his own requirements.
The laid-open specification DE 102005011785 discloses cosmetic O/W emulsions which can also comprise light protection filters. These O/W emulsions are distinguished by an emulsifier combination of non-carbohydrate polyol partial esters of fatty acids, in particular polyglycerol partial esters, and emulsifiers based on carbohydrates, in particular glycosides. With the aid of these specific emulsifier combinations emulsion concentrates are first prepared, which must then be diluted rapidly with water, since they do not have a shelf life.
The object of the present invention is to provide agents having large amounts of UV filters which have a shelf life and thus can also first be converted into O/W emulsions with water after weeks. It should be possible to employ the agents as concentrates, i.e. large amounts of UV filter should be dissolved in large amounts of oils without crystallization of these UV filters occurring during a relatively long storage period. It is also desirable for these agents in the sense of a concentrate to comprise as little water as possible. Furthermore, it should be possible to convert the agents into O/W emulsions for sun protection easily and without the particular presence of shearing forces.
Surprisingly, it has been possible to achieve the object by highly concentrated agents for the preparation of sunscreen final formulations, comprising
The agents according to the invention have a shelf life and show no crystallizing out or sediment of UV filters even after a relatively long storage period. Water can be added to the agents without problems, as a result of which very finely divided sunscreen final formulations of the O/W emulsion type are formed, which in turn also have a very good shelf life and are finely divided homogeneously. Furthermore, the agents in the sense of a concentrate are suitable for giving the user free design possibilities for establishing the desired SPF factor of the sunscreen final formulation.
In the context of the present invention, the SPF factor (sun protection factor, SPF) serves to evaluate light protection preparations (sun creams) on humans (in vivo). It indicates how much longer a person with a sunscreen agent can be exposed to the sun without suffering sunburn than would be possible with the particular individual's self-protection time.
The SPF is determined by the “COLIPA International Sun Protection Factor Test Method” (COLIPA, May 2006), the increase in the skin reddening threshold (minimal erythema dose, MED) after standardized application of light protection preparations being determined as a function of the irradiation time.
In the context of the present invention, possible oily substances (a) are, for example, Guerbet alcohols based on fatty alcohols having 6 to 18, preferably 8 to 10 carbon atoms (e.g. Eutanol® G), esters of linear C6-C22-fatty acids with linear or branched C6-C22-fatty alcohols and esters of branched C6-C13-carboxylic acids with linear or branched C6-C22-fatty alcohols, such as e.g. myristyl myristate, myristyl palmitate, myristyl stearate, myristyl isostearate, myristyl oleate, myristyl behenate, myristyl erucate, cetyl myristate, cetyl palmitate, cetyl stearate, cetyl isostearate, cetyl oleate, cetyl behenate, cetyl erucate, stearyl myristate, stearyl palmitate, stearyl stearate, stearyl isostearate, stearyl oleate, stearyl behenate, stearyl erucate, isostearyl myristate, isostearyl palmitate, isostearyl stearate, isostearyl isostearate, isostearyl oleate, isostearyl behenate, oleyl myristate, oleyl palmitate, oleyl stearate, oleyl isostearate, oleyl oleate, oleyl behenate, oleyl erucate, behenyl myristate, behenyl palmitate, behenyl stearate, behenyl isostearate, behenyl oleate, behenyl behenate, behenyl erucate, erucyl myristate, erucyl palmitate, erucyl stearate, erucyl isostearate, erucyl oleate, erucyl behenate and erucyl erucate. In addition, esters of linear C6-C22-fatty acids with branched alcohols, in particular 2-ethylhexanol, esters of C3-C38-alkylhydroxycarboxylic acids with linear or branched C6-C22-fatty alcohols, in particular diethylhexyl malate, esters of linear and/or branched fatty acids with polyhydric alcohols (such as e.g. propylene glycol, dimer diol or trimer triol) and/or Guerbet alcohols, triglycerides based on C6-C10-fatty acids, liquid mono/di/triglyceride mixtures based on C6-C18-fatty acids, esters of C6-C22-fatty alcohols and/or Guerbet alcohols with aromatic carboxylic acids, in particular benzoic acid, esters of C2-C12-dicarboxylic acids with linear or branched alcohols having 1 to 22 carbon atoms or polyols having 2 to 10 carbon atoms and 2 to 6 hydroxyl groups, plant oils, branched primary alcohols, substituted cyclohexanes, linear and branched C6-C22-fatty alcohol carbonates, such as e.g. Dicaprylyl Carbonate (Cetiol® OE), Guerbet carbonates based on fatty alcohols having 6 to 18 preferably 8 to 10 C atoms, esters of benzoic acid with linear and/or branched C6-C22-alcohols (e.g. Finsolv® TN), linear or branched, symmetric or unsymmetric dialkyl ethers having 6 to 22 carbon atoms per alkyl group, such as e.g. Dicaprylyl Ether (Cetiol® OE), ring-opening products of epoxidized fatty acid esters with polyols (Hydagen® HSP, Sovermol® 750, Sovermol® 1102), silicone oils (cyclomethicone, silicon methicone types and others) and/or aliphatic or naphthenic hydrocarbons, such as e.g. mineral oil, Vaseline, petrolatum, squalane, squalene, isohexadecane or dialkylcyclohexanes are suitable in consideration.
Preferred oily substances (a) are medium-polarity oils, in particular esters of C2-C12-dicarboxylic acids with linear or branched alcohols having 1 to 22 carbon atoms and/or linear and branched C6-C22-fatty alcohol carbonates Adipic acid esters of linear or branched alcohols having 1 to 22 carbon atoms, very particularly of linear alcohols having 1 to 6 carbon atoms, are particularly suitable here.
Linear and branched fatty alcohol carbonates, in particular Dicaprylyl Carbonate, are particularly preferably used as oily substances (a).
Outstanding results are achieved with dibutyl adipate.
Preferably, the oily substances are present in an amount of 20-35 wt. %, based on the agents according to the invention.
The anionic surfactants (b) are characterized by one or more anionic group which confers solubility in water, such as e.g. a carboxylate, sulfate, sulfonate or phosphate group, and a lipophilic radical. In addition the molecule can contain polyglycol ether, ester, ether and hydroxyl groups. Anionic surfactants which are tolerated by skin are known to the person skilled in the art in large numbers from relevant handbooks and are commercially obtainable.
Examples of preferred anionic surfactants are, in each case in the form of their salts, ether-carboxylic acids, acylsarcosides having 8 to 24 C atoms in the acyl group, acyltaurides having 8 to 24 C atoms in the acyl group, acylisethionates having 8 to 24 C atoms in the acyl group, sulfosuccinic acid mono- and dialkyl esters having 8 to 24 C atoms in the alkyl group and sulfosuccinic acid monoalkyl polyoxyethyl esters having 8 to 24 C atoms in the alkyl group and 1 to 6 oxyethyl groups, linear alkanesulfonates having 8 to 24 C atoms, linear alpha-olefinsulfonates having 8 to 24 C atoms, alpha-sulfo-fatty acid methyl esters of fatty acids having 8 to 30 C atoms, alkyl sulfates, alkyl polyglycol ether sulfates, esters of tartaric acid and citric acid, alkyl and/or alkenyl ether phosphates, sulfated fatty acid alkylene glycol esters, monoglyceride sulfates and monoglyceride ether sulfates as well as condensation products of C3-C30-fatty alcohols with protein hydrolysates and/or amino acids and derivatives thereof, so-called protein fatty acid condensates, e.g. Lamepon®, Gluadin®, Hostapon® KCG or Amisoft®.
The salts of these surfactants are preferably selected from the sodium, potassium and ammonium and the mono-, di- and trialkanalammonium salts having 2 to 4 C atoms in the alkanol group.
Particularly suitable anionic surfactants are liquid at room temperature, preferably from 18 to 25° C. A desirable feature in particular of these anionic surfactants is that they have a low water content of at most 10 wt. %, preferably 0.1 to 5 wt. %, based on the anionic surfactant.
Outstandingly suitable surfactants in this context are alk(en)yl polyglycol ether citrates and in particular mixtures of mono-, di- and triesters of citric acid and alkoxylated alcohols which correspond to the formula (I):
R4(OCH2CHR5)n (II)
Typical examples of the alcohol part of the esters are addition products of on average 1 to 20 mol, preferably 5 to 10 mol of ethylene oxide and/or propylene oxide on caproyl alcohol, capryl alcohol, 2-ethylhexyl alcohol, capric alcohol, lauryl alcohol, isotridecyl alcohol, myristyl alcohol, cetyl alcohol, palmitolelyl alcohol, stearyl alcohol, isostearyl alcohol, oleyl alcohol, elaidyl alcohol, petroselinyl alcohol, arachyl alcohol, gadoleyl alcohol, behenyl alcohol, erucyl alcohol and brassidyl alcohol and technical grade mixtures thereof.
It is particularly preferable to use alkyl polyalkylene glycol ether citrates based on addition products of from 5 to 10, in particular approximately 7 mol of ethylene oxide on technical grade C12-C18-, in particular C12-C14-fatty alcohol fractions. The polyethylene glycol ethers of lauryl alcohol, laureth-7 citrates, which are obtainable, for example, under the name Plantapon® LC7 (BASF & Personal Care & Nutrition GmbH), are very particularly preferred.
Such alk(en)yl polyglycol ether citrates are advantageous for the agents according to the invention since they are liquid anionic surfactants having a low water content of max. 5 wt. %, based on the anionic surfactant.
The anionic surfactants (b) are preferably present in amounts of from 7 to 17 wt. %, based on the agents according to the invention.
The agents according to the invention furthermore comprise at least (c) 0.5 to 25 wt. % of a further co-surfactant which differs from (b).
Suitable co-surfactants are, in principle, zwitter-ionic, ampholytic, cationic and/or nonionic surfactants.
Those surface-active compounds which carry at least one quaternary ammonium group and at least one —COO(−) or —SO3(−) group in the molecule are called zwitter-ionic surfactants. Particularly suitable zwitter-ionic surfactants are the so-called betaines, such as the N-alkyl-N,N-dimethylammonium glycinates, for example coco-alkyldimethylammonium glycinate, N-acylaminopropyl-N, N-dimethylammonium glycinates, for example coco-acylamimopropyl-dimethylammonium glycinate, and 2-alkyl-3-carboxymethyl-3-hydroxyethylimidazoline having in each case 8 to 18 C atoms in the alkyl or acyl group, and coco-acylaminoethyl-hydroxyethylcarboxymethyl glycinate. The fatty acid amide derivative known under the INCI name Cocamidopropyl Betaine is a preferred zwitter-ionic surfactant. Tego® Betain 810 (INCI: Capryl/Capramidopropyl Betaine) and a surfactant mixture of Rewopol® SBCS 50K (INCI: Disodium PEG-5 Laurylcitrate Sulfosuccinate, Sodium Laureth Sulfate) and Tego® Betain 810 (Capryl/Capramidopropyl Betaine), in particular in the weight ratio of 1:4 to 4:1, very particularly preferably in the weight ratio of from 1:4 to 1:1, are particularly preferred according to the invention.
Ampholytic surfactants are understood as meaning those surface-active compounds which contain, apart from a C3-C18-alkyl or acyl group, at least one free amino group and at least one —COOH or —SO3H group in the molecule and are capable of formation of inner salts. Examples of suitable ampholytic surfactants are N-alkylglycines, N-alkylpropionic acids, N-alkylaminobutyric acids, N-alkyliminodipropionic acids, N-hydroxyethyl-N-alkylamidopropylglycines, N-alkyltaurines, N-alkylsarcosines, 2-alkylaminopropionic acids and alkylaminoacetic acids having in each case about 8 to 18 C atoms in the alkyl group. Preferred ampholytic surfactants are N-coco-alkylaminopropionate, coco-acylaminoethyl-aminopropionate and C12-18-acylsarcosine.
Quaternary ammonium compounds in particular can be used as cationic surfactants. Surfactants from this substance class have a particularly high affinity for the skin and can improve the degree of sensory smoothness. These include, inter alia, ammonium halides, in particular chlorides and bromides, such as alkyltrimethylammonium chlorides, dialkyldimethylammonium chlorides and trialkylmethylammonium chlorides, e.g. cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, distearyldimethylammonium chloride, lauryldimethylammonium chloride, lauryldimethylbenzylammonium chloride and tricetylmethylammonium chloride. The very readily biodegradable quaternary ester compounds, such as, for example, the dialkylammonium methosulfates and methylhydroxyalkyldialkoyloxyalkylammonium methosulfates marketed under the trade name Stepantex® and the corresponding products of the Dehyquart® series, can furthermore be employed as cationic surfactants. The term “esterquats” is in general understood as meaning quaternized fatty acid triethanolamine ester salts. They impart to the compositions particularly soft feel. These are known substances which are prepared by the relevant methods of organic chemistry. Further cationic surfactants which can be used according to the invention are the quaternized protein hydrolysates.
Nonionic surfactants are particularly preferably present as co-surfactants, for example
The addition products of ethylene oxide and/or of propylene oxide on fatty alcohols, fatty acids, alkylphenols, glycerol mono- and diesters and sorbitan mono- and diesters of fatty acids or on castor oil are known, commercially obtainable products. These are homologue mixtures, the average degree of alkoxylation of which corresponds to the ratio of the substance amounts of ethylene oxide and/or propylene oxide and substrate with which the addition reaction is carried out. They are W/O or O/W emulsifiers, depending on the degree of ethoxylation. For the preparations according to the invention, the reaction products with 1-100 mol of ethylene oxide are particularly suitable.
Advantageous compounds from the group of nonionic surfactants are partial esters of polyols, in particular of C3-C6-polyols, such as, for example, glyceryl monoesters, partial esters of pentaerythritol or sugar esters, e.g. sucrose distearate, sorbitan monoisostearate, sorbitan sesquiisostearate, sorbitan diisostearate, sorbitan triisostearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan dioleate, sorbitan trioleate, sorbitan monoerucate, sorbitan sesquierucate, sorbitan dierucate, sorbitan trierucate, sorbitan monoricinoleate, sorbitan sesquiricinoleate, sorbitan diricinoleate, sorbitan triricinoleate, sorbitan monohydroxystearate, sorbitan sesquihydroxystearate, sorbitan dihydroxystearate, sorbitan trihydroxystearate, sorbitan monotartrate, sorbitan sesquitartrate, sorbitan ditartrate, sorbitan tritartrate, sorbitan monocitrate, sorbitan sesquicitrate, sorbitan dicitrate, sorbitan tricitrate, sorbitan monomaleate, sorbitan sesquimaleate, sorbitan dimaleate, sorbitan trimaleate and technical grade mixtures thereof. Addition products of from 1 to 30, preferably 5 to 10 mol of ethylene oxide on the sorbitan esters mentioned are also suitable nonionic surfactants.
Nonionic surfactants from the group of alkyl oligoglycosides are particularly skin-friendly and may therefore preferably be suitable in the context of the invention. C3-C22-alkyl mono- and oligoglycosides, their preparation and their use are known from the prior art. Their preparation is carried out in particular by reaction of glucose or oligosaccharides with primary alcohols having 8 to 22 C atoms, preferably 12 to 22, and particularly preferably 12 to 18 C atoms. With respect to the glycoside radical, both monoglycosides in which a cyclic sugar residue is bonded glycosidically to the fatty alcohol and oligomeric glycosides having a degree of oligomerization of up to preferably about 8 are suitable. The degree of oligomerization here is a statistical mean based on a conventional distribution of homologues for such technical grade products Products which are available under the name Plantacare® contain a glucosidically bonded C3-C16-alkyl group on an oligoglucoside radical, the average degree of oligomerization of which is 1 to 2. The acylglucamides derived from glucamine are also suitable as nonionic surfactants.
Nonionic surfactants, preferably polyol and/or polyglycerol esters, are very particularly preferably present as co-surfactants in the agents according to the invention as component (c), and/or alkyl oligoglycosides.
The polyol component of these surfactants can be derived from substances which have at least two, preferably 3 to 12 and in particular 3 to 8 hydroxyl groups and 2 to 12 carbon atoms. Typical examples are:
Reaction products based on polyglycerol are of particular importance because of their excellent use properties.
The acid component of these surfactants can be derived from straight-chain, branched, saturated and/or unsaturated carboxylic acids, optionally with functional groups, such as hydroxyl groups. The acid component is particularly preferably fatty acids having 12 to 22 carbon atoms, which optionally carry a hydroxyl group, and in particular hydroxystearic acid.
Reaction product of poly-12-hydroxystearic acid with polyglycerols of the following distribution of homologues have proved to be particularly advantageous as nonionic surfactants (preferred amounts are stated in parentheses):
In a preferred embodiment of the invention the diester of polyhydroxystearic acid, polyglyceryl 2-dipolyhydroxystearate, which is marketed, for example, by BASF Personal Care and Nutrition GmbH under the name Dehymuls® PGPH, is used as a glyceryl ester.
In the agents according to the invention the further co-surfactants are conventionally present in an amount of 0.5-25 wt. %; an amount of 3.0-18 wt. % is preferred, and in particular 7-18 wt. %.
Finally, the agents according to the invention comprise large amounts, i.e. in the range of from 25 to 75 wt. %, preferably 35 to 65 wt. %, in particular 40 to 60 wt. % of UV filters (d).
The following substance classes are preferably employed according to the invention as UV filters corresponding to component (d) (INCI names):
Compounds which can be employed by way of example for p-aminobenzoic acid derivatives (d1) are
PEG-25-PABA of the formula
wherein m, n and x have the same meaning and each denote at most 25; octyldimethyl PABA of the formula
or glycyl aminobenzoate of the formula
Compounds which can be employed by way of example for salicylic acid derivatives (d2) are homomenthyl salicylate of the formula
triethanolamine salicylate of the formula
amyl p-dimethylaminobenzoate of the formula
octyl salicylate of the formula
or 4-isopropylbenzyl salicylate of the formula
Compounds which can be employed by way of example for benzophenone derivatives (d3) are:
Diethylamino Hydroxybenzoyl Hexyl Benzoate corresponding to the formula
is particularly preferred.
Dimeric benzophenone derivatives corresponding to the formula
wherein
In particular, dimeric benzophenone derivatives of the formula
can preferably be employed as UV filters (d3).
Examples of dibenzoylmethane derivatives (d4) which can be employed according to the invention are butylmethoxydibenzoylmethane-[1-(4-tert-butylphenyl)-3-(4-methoxyphenyl)propane-1,3-dione].
Examples of diphenylacrylate derivatives (d5) which can be employed according to the invention are octocrylene-(2-ethylhexyl 2-cyano-3,3′-diphenylacrylate) or etocrylene (ethyl 2-cyano-3,3′-diphenylacrylate).
Examples of benzofuran derivatives (d7) which can be employed according to the invention are 3-(benzofuranyl) 2-cyanoacrylate, 2-(2-benzofuranyl)-5-tert-butylbenzoxazole or 2-(p-aminophenyl)benzofuran and in particular the compounds of the formula
Examples of polymeric UV absorbers (d8) which can be employed according to the invention and contain one or more organosilicon radicals are benzylidenemalonate derivatives, in particular the compound of the formula
wherein R24 denotes hydrogen or methoxy and r denotes approximately 7; the compound of the formula
or polysilicone-15 corresponding to the formula
Examples of cinnamic acid esters (d9) which can be employed according to the invention are octyl methoxycinnamate (4-methoxycinnamic acid 2-ethylhexyl ester), diethanolamine methoxycinnamate (diethanolamine salt of 4-methoxycinnamic acid), isoamyl p-methoxycinnamate (4-ethoxycinnamic acid 2-isoamyl ester), 2,5-diisopropyl methycinnamate or a cinnamic acid amido derivative.
Examples of camphor derivatives (d10) which can be used according to the invention are 4-methylbenzylidenecamphor[3-(4′-methyl)benzylidenebornan-2-one], 3-benzylidenecamphor (3-benzylidenebornan-2-one), polyacrylamidomethylbenzylidenecamphor {N-[2(and 4)-2-oxyborn-3-ylidenemethyl)benzyl]acrylamide polymer}, trimoniumbenzylidenecamphor sulfate-[3-(4′-trimethylammonium)-benzylidenebornan-2-one methylsulfate], terephthalydenedicamphorsulfonic acid {3,3′-(1,4-phenylenedimethine)-bis-(7,7-dimethyl-2-oxobicyclo-[2.2.1]heptane-1-methanesulfonic acid} or salts thereof, or benzylidenecamphorsulfonic acid [3-(4′-sulfo)benzylidenebornan-2-one] or salts thereof.
Examples of hydroxyphenyltriazine derivatives (d11) which can be used according to the invention are, in particular, bis-resorcinyltriazines of the formula
Examples of representatives of the compound class (d11) which may be mentioned are:
Examples of benzotriazole derivatives (d12) which can be used according to the invention correspond to the formula
Preferably, compounds of the formula (BT-01), wherein
Very particularly preferred compounds are those of the formula
Furthermore, preferred UV filters of the formula BT-01 are those wherein
Very particularly preferred compounds are those of the formula
Examples of trianilino-s-triazine derivatives (d13) which can be used according to the invention correspond to the formula
A particularly preferred representative of this compound class is Ethylhexyl Triazone corresponding to the formula
or Diethylhexyl Butamido Triazone corresponding to the formula
or Ethylhexyl Bis-Isopentylbenzoxazolylphenyl Melamine corresponding to the formula
Preferred tris-biphenyl-triazine derivatives (d17) which can be used according to the invention correspond to the formula
wherein
wherein in formula (TBT-01a) at least one of the radicals R2, R3 and R4 denotes a radical of the formula (TBT-01c);
Preferably, the UV filters (d17) which can be used according to the invention correspond to the compounds of the formula
Preferred benzylidenemalonates (d19) which can be employed according to the invention correspond to the formula
wherein
Particularly preferred benzylidenemalonates (d19) which can be employed according to the invention are listed in the following table:
An example of a representative of phenylene-bis-diphenyltriazines (d21) is 5,6,5,6-tetraphenyl-3,3′-(1,4-phenylene)-bis[1,2,4]triazine corresponds to the formula
An example of a representative of imidazoline derivatives is Ethyl hexyldimethoxybenzylidenedioxoimidazoline Propionate
An example of a representative of diarylbutadiene derivatives (d23) is 1,1-dicarboxy-(2,2′-dimethylpropyl)-4,4-diphenylbutadiene.
Each of the abovementioned UV filters (d1)-(d23) can be used according to the invention as a mixture. For example, mixtures of two, three, four, five or six of the filter groups (d1)-(d23) can be used according to the invention. Mixtures of two, three, four, five or six UV filters from one or more representatives of substance classes (d1)-(d23) can also be used according to the invention.
Preferably, UV filters (d) are used according to the invention, in particular representatives of the following compound classes:
Particularly preferably, the following oil-soluble UV filters are used according to the invention:
UV filters which are very particularly preferred in the context of the present invention are oil-soluble filter mixtures of
Possible UV filter mixtures according to the invention of oil-soluble UV filters (UV SOL 1-UV SOL 551) are listed in the table below:
Large amounts of UV filter can advantageously be incorporated, so that the agents according to the invention are oily concentrates of UV filters which can be converted later with desired amounts of water into sunscreen final formulations. The absolute amount of UV filters here depends on the nature chosen for the UV filter, the desired dilution of the sunscreen final formulation and the desired sun protection factor.
Although the agent according to the invention tolerates relatively large amounts of water, in the context of the invention an oily concentrate is desired, so that the amounts of water are preferably as low as possible.
In the context of the invention it is therefore preferable for the agents according to the invention to have no or only small amounts of water of less than 10 wt. %, preferably 0 to 5 wt. %.
With the agents according to the invention it is now possible to achieve sunscreen final formulations having high SPF values, preferably of up to 50+, via the amount and choice of the UV filters incorporated.
The sun protection simulators, for example, of BASF Personal Care and Nutrition GmbH can be used for determining the SPF values.
Finally, the agents according to the invention can comprise water and/or auxiliary substances to 100 wt. %.
Auxiliary substances concentration be, for example, pH adjusters. For example triethanolamine, monoethanolamine or Tetrahydroxypropyl Ethylenediamine. Triethanolamine is preferred.
Agents which are suitable according to the invention are those which comprise
Agents which are particularly preferred are those which comprise
The agents according to the invention can be prepared on the laboratory scale by simple, manual stirring at room temperature or, if they comprise a substance which is solid at room temperature, at elevated temperatures. Preferably, the oily substance (a) is initially introduced into the mixing vessel and the UV filters (d) are stirred in, preferably at elevated temperatures and in particular at 85 to 95° C. Clear mixtures are obtained and are preferably cooled to room temperature before the anionic surfactants (b) and co-surfactants (c) and optionally auxiliary substances are stirred in. Additional water which is not incorporated in the form of aqueous formulations of the surfactants and/or auxiliary substances can be added in the last process step, but in the context of the invention is not desired.
In a further preferred preparation procedure, the oily substance (a) is initially introduced into the mixing vessel and the UV filters (d) are stirred in, preferably at elevated temperatures and in particular at 85 to 95° C. Thereafter, the anionic surfactants (b) and the co-surfactants (c) are stirred in. The mixture is then cooled. Auxiliary substances are then optionally also added, such as e.g. pH adjusters or additional alkyl polyglucoside. A clear mixture is obtained by this procedure.
The clear concentrates having a high content of UV filter(s) are furthermore distinguished by a very long shelf life of several weeks.
The present invention also provides a process for the preparation of sunscreen final formulations. The process is characterized in that the agents as claimed in claim 1 are diluted with water and optionally further UV filters and optionally conventional further auxiliary substances at temperatures in the range of from 5 to 30° C.
Advantageously, the dilution is carried out in a so-called cold process, that is to say at room temperature, preferably in the range of from 20 to 25° C., the agents according to the invention being converted into the sunscreen final formulations with water and optionally conventional further auxiliary substances.
The UV filters (d1)-(d20) already mentioned can be added to the agents according to the invention as further UV filters. Examples of substances are mentioned in the following Table 3:
Each of the UV filters listed in the above table can be used as an additional filter in the composition according to the invention. One, two, three, four, five or six further UV filters can be employed.
Particularly finely divided and skin-friendly O/W sunscreen final formulations are obtained by the process according to the invention if the highly concentrated agents according to the invention are homogenized in amounts of from 6 to 50 wt. %, preferably >10 to 50 wt. %, and in particular from 15 to 50 wt. %, based on the O/W sunscreen final formulation, with water and optionally auxiliaries.
The homogenization is preferably carried out under moderate mechanical action, that is to say by simple stirring. Particular shearing forces are possible, but not necessary.
It has proved advantageous for thickeners already to be present as further auxiliaries during the dilution with water. Suitable thickeners are anionic, zwitter-ionic, amphoteric and nonionic copolymers, such as, for example, vinyl acetate/crotonic acid copolymers, vinylpyrrolidone/vinyl acrylate copolymers, vinyl acetate/butyl maleate/isobornyl acrylate copolymers, methyl vinyl ether/maleic anhydride copolymers and esters thereof, acrylamidopropyltrimethylammonium chloride/acrylate copolymers, octylacrylamide/methyl methacrylate/tert-butylaminoethyl methacrylate/2-hydroxypropyl methacrylate polymers, vinylpyrrolidone/vinyl acetate copolymers, vinylpyrrolidone/dimethylaminoethyl methacrylate/vinylcaprolactam terpolymers and optionally polysaccharides, in particular xanthan gum, guar and guar derivatives, agar-agar, alginates and tyloses, cellulose and cellulose derivatives, such as carboxymethylcellulose, carboxymethylcellulose and hydroxycellulose and moreover silicones. Preferably, thickeners from the group of polyacrylates and crosslinked polyacrylates, such as Rheocare TTA®, Cosmedia® SP, Rheocare® C Plus, Tinovis® ADE, Tinovis® GTC, are added, and in particular preferably in amounts of from 0.5 to 5, in particular from 1. to 4 wt. %, calculated as active substance and based on the sunscreen final formulation. Thickeners from the group of polysaccharides, such as Keltrol® T or Rheocare® XG, are furthermore preferred.
The thickeners can be added to the concentrated agent before the dilution with water is carried out or can be contained in the water with which the dilution of the concentrated agent is carried out.
According to a preferred process variant, the concentrated agent is mixed with the thickener, and water for dilution is added to this mixture and the further formulation constituents are optionally stirred in.
According to another preferred process variant, the water, the thickener and optionally the other auxiliary substances are stirred with one another and the concentrated agent is added to this mixture.
The sunscreen final formulations prepared by the process according to the invention are often particularly finely divided O/W emulsion having an average particle size of <10 μm, preferably <5 μm.
The present invention also provides the use of the concentrated agents as claimed in claim 1 for the preparation of cosmetic formulations having a very high sun protection factor, preferably having an SPF of up to 50+.
If desired, the sunscreen final formulations can comprise further auxiliary substances, such as moisture-retaining agents/skin-moisturizing agents, viscosity regulators, oils, fats and waxes, surfactants, pearlescent waxes, super-oiling agents, stabilizers, cationic, zwitter-ionic or amphoteric polymers, further UV filters, biogenic active compounds, film-forming agents, swelling agents, hydrotropic substances, preservatives, solubilizers, perfume oils, dyestuffs, insect repellant active compounds etc., which are listed below by way of example.
Moisture-retaining agents serve to further optimize the sensory properties of the composition and for moisture regulation of the skin. The moisture-retaining agents can be present in an amount of 0-5 wt. %. Suitable substances are, inter alia, amino acids, pyrrolidonecarboxylic acid, lactic acid and salts thereof, lactitol, urea and urea derivative, uric acid, glucosamine, creatinine, collagen cleavage products, chitosan or chitosan salts/derivatives, and in particular polyols and polyol derivatives (e.g. glycerol, diglycerol, triglycerol, ethylene glycol, propylene glycol, butylene glycol, erythritol, 1,2,6-hexanetriol, polyethylene glycols, such as PEG-4, PEG-6, PEG-7, PEG-8, PEG-9, PEG-10, PEG-12, PEG-14, PEG-16, PEG-18, PEG-20), sugars and sugar derivatives (inter alia fructose, glucose, maltose, maltitol, mannitol, inositol, sorbitol, sucrose, sorbitylsilanediol, sucrose, trehalose, xylose, xylitol, glucuronic acid and salts thereof), ethoxylated sorbitol (sorbeth-6, sorbeth-20, sorbeth-30, sorbeth-40), honey and hardened honey, hardened starch hydrolysates and mixtures of hardened wheat protein and PEG-20/acetate copolymer. Substances which are preferably suitable according to the invention as moisture-retaining agents are glycerol, diglycerol, triglycerol and butylene glycol.
Possible insect repellants are, for example, N,N-diethyl-m-toluamide, 1,2-pentanediol or 3-(N-n-butyl-N-acetylamino)propionic acid ethyl ester), which is marketed by Merck KGaA under the name Insect Repellent 3535, and butylacetylaminoproprionate. They are conventionally employed in the compositions according to the invention in an amount of 0-6 wt. %, based on the agent.
The viscosity of the agents according to the invention can be achieved by addition of viscosity regulators. Possible viscosity regulators are, inter alia, agents which impart consistency, such as e.g. fatty alcohols or hydroxy-fatty alcohols having 12 to 22 and preferably 16 to 18 carbon atoms and partial glycerides, fatty acids having 12 to 22 carbon atoms or 12-hydroxy-fatty acids. A combination of these substances with alkyl oligoglucosides and/or fatty acid N-methylglucamides of the same chain length is also suitable, since such combinations deliver particularly stable and homogeneous emulsions. The viscosity regulators also include thickening agents, such as, for example, Aerosil types (hydrophilic silicic acids), polysaccharides, in particular xanthan gum, guar-guar, agar-agar, alginates and tyloses, carboxymethylcellulose and hydroxyethyl- and hydroxypropylcellulose, furthermore higher molecular weight polyethylene glycol mono- and diesters of fatty acids, polyacrylates (e.g. Carbopols® and Pemulen types from Goodrich; Synthalens® from Sigma; Keltrol types from Kelco; Sepigel types from Seppic; Salcare types from Allied Colloids), non-crosslinked and polyol-crosslinked polyacrylic acids, polyacrylamides, polyvinyl alcohol and polyvinylpyrrolidone. Bentonites, such as e.g. Bentone® Gel VS-5PC (Rheox), which is a mixture of cyclopentasiloxane, Disteardimonium Hectorite and propylene carbonate, have also proved to be particularly effective. Surfactants, such as, for example, ethoxylated fatty acid glycerides, esters of fatty acids with polyols, such as, for example, pentaerythritol or trimethylolpropane, fatty alcohol ethoxylates with a narrowed homologue distribution, alkyl oligoglucosides and electrolytes, such as e.g. sodium chloride and ammonium chloride, can also be employed for regulation of the viscosity.
In the context of the invention fats and waxes are understood as meaning all lipids having a fat- or wax-like consistency which have a melting point above 20° C. These include, for example, the classic triacylglycerols, that is to say the triesters of fatty acids with glycerol, which can be of plant or animal origin. These can also be mixed esters, that is to say triesters of glycerol with various fatty acids, or a mixture of various glycerides. These also include mixtures of mono-, di- and triglycerides. So-called hardened fats and oils which are obtained by partial hydrogenation are particularly suitable according to the invention. Hardened fats and oils of plants are preferred, e.g. hydrogenated castor oil, groundnut oil, soya oil, rape oil, beet seed oil, cottonseed oil, soya oil, sunflower oil, palm oil, palm kernel oil, linseed oil, almond oil, maize oil, olive oil, sesame oil, cacao butter and coconut fat. Oxidation-stable plant glycerides which are available under the name Cegesoft® or Novata® are particularly suitable.
Possible waxes are, inter alia, natural waxes, such as e.g. candelilla wax, carnauba wax, Japan wax, esparto grass wax, cork wax, guaruma wax, rice germ oil wax, sugar cane wax, ouricury wax, montan wax, beeswax, shellac wax, spermaceti, lanolin (wool wax), uropygium fat, ceresin, ozocerite (earth wax), petrolatum, paraffin waxes, microwaxes; chemically modified waxes (hard waxes), such as e.g. montan ester waxes, Sasol waxes, hydrogenated jojoba waxes and synthetic waxes, such as e.g. polyalkylene waxes and polyethylene glycol waxes.
In addition to the fats, fat-like substances, such as lecithins and phospholipids, are also possible as additives. Lecithins are glycero-phospholipids which are formed from fatty acids, glycerol, phosphoric acid choline by esterification, and are often also called phosphatidylcholines (PC). Cephalins, which are also called phosphatidic acids and are derivatives of 1,2-diacyl-sn-glycerol-3-phosphoric acids, may be mentioned as an example of natural lecithins. In contrast, phospholipids are usually understood as meaning mono- and preferably diesters of phosphoric acid with glycerol (glycerol phosphates). Sphingosines and sphingolipids are also possible as fat-like substances.
Suitable pearlescent waxes are, for example, alkylene glycol esters, specifically ethylene glycol distearate; fatty acid alkanolamides, specifically coconut fatty acid diethanolamide; partial glycerides, specifically stearic acid monoglyceride; esters of polybasic, optionally hydroxy-substituted carboxylic acids with C6-C22-fatty alcohols, specifically long-chain esters of tartaric acid; fatty substances, such as, for example, fatty alcohols, fatty ketones, fatty aldehydes, fatty ethers and fatty carbonates, which have at least 24 carbon atoms in total—specifically Lauron®; distearyl ether; fatty acids, such as stearic acid, C12-C22-hydroxy-fatty acids, behenic acid, ring-opening products of C12-C22-olefin epoxides with C12-C22-fatty alcohols and/or polyols having 2 to 15 carbon atoms and 2 to 10 hydroxyl groups and mixtures thereof.
Super-oiling agents which can be used are substances such as, for example, lanolin and lecithin and polyethoxylated or acylated derivatives of lanolin and lecithin, polyol fatty acid esters, monoglycerides and fatty acid alkanolamides, the latter simultaneously serving as foam stabilizers.
So-called stabilizers which can be employed are metal salts of fatty acids, such as e.g. magnesium, aluminum and/or zinc stearate or ricinoleate.
Suitable cationic polymers which further optimize the sensory properties of the compositions according to the invention and impart to the skin a sensation of softness are, for example, cationic cellulose derivatives, such as e.g. a quaternized hydroxyethylcellulose which is obtainable from Amerchol under the name Polymer JR 400®, cationic starch, copolymers of diallylammonium salts and acrylamides, quaternized vinylpyrrolidone/vinylimidazole polymers, such as e.g. Luviquat® (BASF), condensation products of polyglycols and amines, quaternized collagen polypeptides, such as, for example, Lauryldimonium Hydroxypropyl Hydrolyzed Collagen (Lamequat®L/Grunau), quaternized wheat polypeptides, polyethylenimine, cationic silicone polymers, such as e.g. amodimethicone, copolymers of adipic acid and dimethylaminohydroxypropyldiethylenetriamine (Cartaretine®/Sandoz), copolymers of acrylic acid with dimethyldiallylammonium chloride (Merquat® 550/Chemviron, polyaminopolyamides and crosslinked water-soluble polymers thereof, cationic chitin derivatives, such as, for example, quaternized chitosan, condensation products, optionally distributed in microcrystalline form, of dihaloalkyls, such as e.g. dibromobutane with bisdialkylamines, such as e.g. bis-dimethylamino-1,3-propane, cationic guar gum, such as e.g. Jaguar® CBS, Jaguar® C-17, Jaguar® C-16 from Celanese, quaternized ammonium salt polymers, such as e.g. Mirapol® A-15, Mirapol®AD-1, Mirapol® AZ-1 from Miranol.
Starch derivative can furthermore be employed to improve the skin sensation, e.g. Dry Flo® PC (INCI: Aluminum Starch Octenylsuccinate).
Suitable silicone compounds have already been mentioned with the oily substances. In addition to dimethylpolysiloxanes, methylphenylpolysiloxanes and cyclic silicones, amino-, fatty acid-, alcohol-, polyether-, epoxy-, fluorine-, glycoside- and/or alkyl-modified silicone compounds, which can be either liquid or resinous at room temperature, are also suitable. Simethicones, which are mixtures of dimethicones having an average chain length of from 200 to 300 dimethylsiloxane units and silicon dioxide or hydrogenated silicates, are furthermore suitable.
Biogenic active compounds which are suitable according to the invention are to be understood as meaning, for example, tocopherol, tocopherol acetate, tocopherol palmitate, ascorbic acid, (deoxy)ribonucleic acid and fragmentation products thereof, β-glucans, retinol, bisabolol, allantoin, phytantriol, panthenol, AHA acids, amino acids, ceramides, pseudoceramides, essential oils, plant extracts, such as e.g. Prunus extract, Bambara nut extract and vitamin complexes. Such active compounds are employed in sunscreen final formulations as agents which trap free radicals, and serve to regenerate the skin.
So-called film-forming agents which lead to a further improvement in the sensory properties of the preparations according to the invention are, for example, chitosan, microcrystalline chitosan, quaternized chitosan, collagen, hyaluronic acid and salts thereof and similar compounds, and the polyvinylpyrrolidones, vinyl pyrrolidone/vinyl acetate copolymers, polymers of the acrylic acid series and quaternized cellulose derivatives already mentioned under the viscosity regulators.
To improve the flow properties of the compositions according to the invention hydrotropic substances, such as, for example, ethanol, isopropyl alcohol, or polyols, can furthermore be employed. Polyols which are possible here have preferably 2 to 15 carbon atoms and at least two hydroxyl groups. The polyols can also contain further functional groups, in particular amino groups, or can be modified with nitrogen.
Suitable preservatives are, for example, phenoxyethanol, formaldehyde solution, parabens, pentanediol or sorbic acid and the silver complexes known by the name Surfacine®.
Perfume oils which may be mentioned are natural, plant and animal as well as synthetic odoriferous substances or mixtures thereof. Natural odoriferous substances are obtained, inter alia, by extraction of flowers, stems, leaves, fruit, fruit peel, roots and resins of plants. Animal raw materials are furthermore possible, such as, for example, civet and castoreum. Typical synthetic odoriferous compounds are products of the ester, ether, aldehyde, ketone, alcohol and hydrocarbon type. Preferably, mixtures of various odoriferous substances which together generate a pleasant fragrance note are used.
Dyestuffs which can be used are the substances which are suitable and approved for cosmetic purposes.
The following examples serve to illustrate the invention, without limiting this to the examples.
Data calculated as active substance in wt. %
The concentrates according to the invention are prepared by mixing the oily component (a) (Dicaprylyl Carbonate or Dibutyl Adipate) with the UV filters (d) (Ethylhexyl Methoxycinnamate, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Ethylhexyl Triazone, Diethylamino Hydroxybenzoyl Hexyl Benzoate), while heating to 90 to 95° C. After a clear solution is obtained this is cooled to room temperature and the anionic surfactant (b) (Laureth-7 Citrate) and the co-surfactant (c) (Polyglyceryl-2 Dipolyhydroxystearate) are stirred in.
Storage-stable concentrates which even after storage for several weeks at room temperature show no sediment or formation of crystals of the UV filter are obtained.
As a comparison, corresponding concentrates are prepared, but without anionic surfactant (b) (Laureth-7 Citrate) according to Com. 2 or without co-surfactant (c) (Polyglyceryl-2 Dipolyhydroxystearate) according to Com. 1 or completely without surfactants according to Com. 3. The concentrate according to Com. 1 is cloudy, the concentrate according to Com. 2 is slightly cloudy. The concentrate according to Com. 3 forms undesirable crystals during storage within 4 weeks. Furthermore, the concentrate according to Com. 3 is not self-emulsifying on dilution with water.
For sunscreen composition B1 the thickener is homogenized with water and all the other constituents apart from the concentrate and the mixture is introduced into the mixing vessel. The concentrate according to Example A3 is then added to this and all the components are homogenized with the magnetic stirrer. The pH is adjusted to 6.5.
For sunscreen composition B2 the thickener is mixed with the concentrate according to Example A3 and the mixture is introduced into the mixing vessel. Water is then added as well as the remainder of the recipe substances and all the components are homogenized with the magnetic stirrer. The pH is adjusted to 5.0.
For sunscreen composition B3, which comprises no thickener, water and the remainder of the recipe substances are added and all the components are homogenized with the magnetic stirrer. The pH is adjusted to 5.0.
For comparison purposes the concentrates from Table 1 Com. 1, Com. 2 and Com. 3 are dispersed in water in order to test the self-emulsifying properties. While finely divided 01W emulsions having a particle diameter in the region of less than 5 μm are formed with the concentrates according to the invention, the dispersions with the comparison concentrates are unstable and a distinct phase separation occurs after one day. Com. 3 in particular forms no emulsion in the dilution with water.
Butyrospermum Parkii (Shea Butter)
| Number | Date | Country | Kind |
|---|---|---|---|
| 13167285.9 | May 2013 | DE | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP14/59187 | 5/6/2014 | WO | 00 |
