DE102017114423A1 - Use of alkylresorcinols for improving the efficacy of cosmetic preservatives - Google Patents

Abstract

The invention relates to the use of alkylresorcinols for improving the antimicrobial effectiveness of cosmetic preservatives, wherein the amount of alkylresorcinol is at most 0.2% by weight, based on the weight of the cosmetic.

Description

The present invention relates to the use of alkylresorcinols for improving the antimicrobial efficacy of cosmetic preservatives. Moreover, the invention relates to a concentrate comprising i) alkylresorcinol and ii) conventional preservative, as well as the use of the concentrate for the preservation of cosmetics.

For the preservation of cosmetics substances are used, some of which are listed as approved preservatives in Annex V of Regulation (EU) No 1223/2009. These listed substances are limited in their use concentration and do not always lead to the desired preservation when used alone in the maximum permitted concentration. Some of the substances used also show disadvantages such as an undesirable odor, discoloration or harmful effects on the stability of the cosmetic preparations. It can also lead to the breaking of emulsions or to massive viscosity changes.

To overcome these disadvantages, so-called boosters are used. These substances show no or only a very low own antimicrobial effectiveness in the concentration used, but are suitable to increase the effect of other preserving ingredients and thus open up the possibility of reducing their necessary content and thus to optimize the use of preservatives economically and ecologically , These interactions are also referred to as synergism. Known substances of this category are various alkanediols, e.g. 1,2-octanediol, as well as complexing agents and also 1- (2-ethylhexyl) glycerol.

In addition, the use of resorcinols is known in cosmetics. For example, the DE 10 2008 041 971 A1 a procedure for the reduction of age spots. For this purpose, a cosmetic or pharmaceutical preparation is used which may contain, for example, 4-butylresorcinol (rucinol) or 4-hexylresorcinol.

The WO 2008/058680 describes a cosmetic skin lightening composition containing a combination of a) skin lightening agent and b) glucosylglyceride.

The US 2009/0148391 A1 discloses compositions for lightening skin or hair containing, for example, 0.5 to 5% by weight of 4-butylresorcinol.

The EP 1 374 849 A1 discloses cosmetic compositions for bleaching skin or hair which, in addition to ascorbic acid (derivatives), may also contain depigmenting agents such as 4-butylresorcinol.

In the GB 0910629 It is about cosmetic hair dye products containing, for example, butylresorcinol as an antioxidant, to avoid resulting in the oxidation of the dyes, the skin-irritating degradation products.

In the EP 2 149 364 A1 discloses antifungal cosmetic preparations containing 2-methyl-4-isothiazolin-3-one, further containing hydroquinone radical scavengers.

The DE 10 2013 217 244 A1 describes emulsifier-free cosmetic preparations which may further contain whitening substances such as rucinol.

In addition, there are a variety of substances that are used for the preservation of cosmetics. However, these known cosmetic preservatives, when used in the amounts necessary (and often undesirably high) for the antimicrobial finish, can result in skin irritation or other cosmetic topical undesirable effects or adversely affect other cosmetic properties (such as viscosity).

Accordingly, the present invention has the object to show advantageous ways for the preservation of cosmetics.

It has now surprisingly been found that alkylresorcinols in a low use concentration cause an increase in the effectiveness of conventional cosmetic preservatives. The required use concentrations of alkylresorcinols lie in a range in which the known lightening of the skin does not occur. For example, the addition of 0.1 wt .-% 4-hexylresorcinol or 0, 1% 4-butylresorcinol in a model cream is not used to make this model cream skin whitening (a difference between a preparation with 0.1% 4-hexylresorcinol or 0.1% 4-butylresorcinol and a placebo preparation could not be detected) , In contrast, the effect of conventional cosmetic preservatives is increased in these small amounts, wherein the inventive combinations of alkylresorcinol with conventional Kosmetikkonservierungsstoff the cosmetics advantageously confer no skin whitening effect.

In a first aspect, the invention thus relates to the use of alkylresorcinols for improving the antimicrobial efficacy of cosmetic preservatives.

In a second aspect, the invention relates to concentrates comprising alkylresorcinol and cosmetic preservative.

In a third aspect, the invention relates to the use of the concentrate for the preservation of cosmetics.

The present invention accordingly relates to the use of alkylresorcinols in cosmetics in order to be able to reduce the necessary content of other preserving constituents and thus to optimize their use economically and ecologically and to overcome regulatory restrictions. Although alkylresorcinols, even without combination with other active ingredients, exhibit antimicrobial activity, but not in the use concentrations required for the enhancement of the invention. These are so low that the Alkylresorcinole not show their own antimicrobial activity, as shown below in the examples.

The object is achieved in particular by providing a combination of alkylresorcinols, such as 4-butylresorcinol or 4-hexylresorcinol, with known active ingredients for cosmetic preservation, such as aromatic alcohols (such as benzyl alcohol, phenoxyethanol, phenylethyl alcohol, phenoxyisopropanol, dichlorobenzyl alcohol and phenylpropanol) or polyhydric aliphatic alcohols (such as 1,2-pentanediol, chlorphenesin, 1,2-hexanediol, 1,2-octanediol and 1,3-propanediol). In addition, further classes of substances, such as organic acids (such as benzoic acid, sorbic acid, salicylic acid, anisic acid, dehydroacetic acid, 4-hydroxybenzoic acid) or their salts or esters can be used. Furthermore, formaldehyde, paraformaldehyde or Formaldhydabspalter (such as methenamine, DMDM-hydantoin, diazolidinylurea, Imidazolidinylharnstoff, sodium hydroxymethylglycinate, 7-Ethylbicyclooxazolidin, Benzylhemiformal, hexetidine, Quaternium-15 or Bronidox and Bronopol) can be combined. Also suitable are heterocyclic active compounds (such as, for example, methylchloroisothiazolinone, methylisothiazolinone, pyrithione zinc, piroctone olamine or climbazoles). In addition, known phenol derivatives (such as chlorocresol, triclosan, chlorxylenol, bromochlorophene, o-cymene-5-ol, chlorophen, 2-hydroxybiphenyl) or salts thereof are suitable for their preservative effectiveness. Further, quaternary ammonium salts (such as alkyl (C _12-22 ) trimethylammonium bromide and chloride, benzalkonium chloride, benzethonium chloride, octenidine dihydrochloride and also biguanides and amidines (such as dibromohexamidine, hexamidine, chlorhexidine or polyaminopropylbiguanide) may be used in the combinations found. such as glutaraldehyde) or amino acid derivatives (such as ethyl lauroylarginate HCl) are also organic halogen compounds (such as triclocarban, chloroacetamide, 3-iodo-2-propinylbutylcarbamat, chlorobutanol) promising combination partner for Alkylresorcinole.

The combinations of i) alkylresorcinol and ii) cosmetic preservative may be formed in the products to be preserved by separate metering of the individual components in the preparation of the cosmetic product, or provided in the form of a premix. Premixes, especially of a liquid type, offer the processing plant easier handling and a smaller number of individual raw materials to be kept, which also means less effort in the incoming goods inspection.

An exemplary embodiment as a liquid preparation preferably contains one, two or more alkylresorcinols in one, two or more aromatic alcohols, and optionally further solvents, microbicidal agents, one, two or more selected stabilizers and optionally further functional additives or auxiliaries.

Also claimed is the use of alkylresorcinols in cosmetic products for synergistically enhancing the efficacy of preserving ingredients.

1. i) mindestens ein Alkylresorcinol bzw. dessen Salze, bevorzugt 4-Butylresorcinol oder 4-Hexylresorcinol und
2. ii) mindestens einen aromatischen Alkohol, bevorzugt Phenoxyethanol, Benzylalkohol oder Phenylpropanol sowie
3. iii) gegebenenfalls ein Lösungsmittel (wie etwa Wasser, Alkohole oder Glykole oder Glykolether) sowie iv) gegebenenfalls weitere mikrobizide Wirkstoffe, funktionelle Additive oder Hilfsstoffe.

Also claimed is a concentrate preparation comprising:

1. i) at least one alkylresorcinol or its salts, preferably 4-butylresorcinol or 4-hexylresorcinol and
2. ii) at least one aromatic alcohol, preferably phenoxyethanol, benzyl alcohol or phenylpropanol, and
3. iii) optionally a solvent (such as water, alcohols or glycols or glycol ethers) and iv) optionally further microbicidal agents, functional additives or auxiliaries.

Claimed is also the use of said combination of ingredients for the preservation of cosmetic products.

Detailed description of the invention

According to the first aspect, the invention relates to the use of one, two or more alkyl resorcinols for improving the antimicrobial efficacy of one, two or more cosmetic preservatives, wherein the amount of alkylresorcinol is at most 0.2% by weight, based on the weight of the cosmetic ,

The amount of alkylresorcinol used according to the invention is preferably from 0.01 to 0.15% by weight, more preferably from 0.02 to 0.12% by weight, in particular from 0.03 to 0.1% by weight, based in each case on the Weight of the cosmetic.

Preferred alkylresorcinols used according to the invention are 4-alkylresorcinols.

A preferred alkyl group of the alkylresorcinol is selected from linear or branched alkyl groups, wherein the alkyl group is preferably a linear alkyl group.

In addition, it is preferred according to the invention that the alkyl group is a C ₂ - to C ₁₀ -alkyl group, preferably a C ₃ - to C ₈ -alkyl group, such as a butyl or hexyl group, wherein the alkyl group is in particular a butyl group.

In all embodiments of the invention, it is particularly preferred that 4-n-butylresorcinol is used as the alkylresorcinol.

Cosmetic preservatives used in combination with alkylresorcinols according to the invention are listed in Annex V to Regulation (EU) No. 1223/2009 as authorized preservatives.

1. a) aromatischen Alkoholen, wie Benzylalkohol, Phenoxyethanol, Phenylethylalkohol, Phenoxyisopropanol, Dichlorbenzylalkohol und Phenylpropanol),
2. b) mehrwertigen aliphatischen Alkoholen (wie 1,2-Pentandiol, Chlorphenesin, 1,2-Hexandiol, 1,2-Octandiol und 1,3-Propandiol),
3. c) organischen Säuren (wie Benzoesäure, Sorbinsäure, Salicylsäure, Anissäure, Dehydracetsäure, 4-Hydroxybenzoesäure) oder deren Salzen oder Estern,
4. d) Formaldehyd, Paraformaldehyd oder Formaldhydabspaltern (wie Methenamin, DMDM-Hydantoin, Diazolidinylharnstoff, Imidazolidinylharnstoff, Natrium-Hydroxymethylglycinat, 7-Ethylbicyclooxazolidin, Benzylhemiformal, Hexetidin, Quaternium-15, Bronidox und Bronopol),
5. e) heterocyclischen Wirkstoffen (wie Methylchlorisothiazolinon, Methylisothiazolinon, Pyrithion-Zink, Piroctone-Olamine oder Climbazole),
6. f) Phenolderivaten (wie Chlorkresol, Triclosan, Chloroxylenol, Bromochlorophene, o-Cymen-5-ol, Chlorophene, 2-Hydroxybiphenyl) oder deren Salzen,
7. g) quartären Ammoniumsalzen (wie Alkyl (C_12-22) trimethylammoniumbromid und -chlorid, Benzalkoniumchlorid, Benzethoniumchloride, Octenidindihydrochlorid),
8. h) Biguaniden und Amidinen (wie Dibromhexamidin, Hexamidin, Chlorhexidin oder Polyaminopropylbiguanid),
9. i) Aldehyden (wie Glutaraldehyd),
10. j) Aminosäurederivaten (wie Ethyllauroylarginat-HCl) und
11. k) organischen Halogenverbindungen (wie Triclocarban, Chloracetamid, 3-Iod-2-propinylbutylcarbamat).

Cosmetic preservatives preferably used according to the invention are selected from

1. a) aromatic alcohols, such as benzyl alcohol, phenoxyethanol, phenylethyl alcohol, phenoxyisopropanol, dichlorobenzyl alcohol and phenylpropanol),
2. b) polyhydric aliphatic alcohols (such as 1,2-pentanediol, chlorphenesin, 1,2-hexanediol, 1,2-octanediol and 1,3-propanediol),
3. c) organic acids (such as benzoic acid, sorbic acid, salicylic acid, anisic acid, dehydroacetic acid, 4-hydroxybenzoic acid) or their salts or esters,
4. d) formaldehyde, paraformaldehyde or formaldehyde splitting agents (such as methenamine, DMDM-hydantoin, diazolidinylurea, imidazolidinylurea, sodium hydroxymethylglycinate, 7-ethylbicyclooxazolidine, benzylhemiformal, hexetidine, quaternium-15, Bronidox and Bronopol),
5. e) heterocyclic active substances (such as methylchloroisothiazolinone, methylisothiazolinone, pyrithione-zinc, piroctone-olamine or climbazole),
6. f) phenol derivatives (such as chlorocresol, triclosan, chloroxylenol, bromochlorophene, o-cymene-5-ol, chlorophene, 2-hydroxybiphenyl) or their salts,
7. g) quaternary ammonium salts (such as alkyl (C _12-22 ) trimethylammonium bromide and chloride, benzalkonium chloride, benzethonium chlorides, octenidine dihydrochloride),
8. h) biguanides and amidines (such as dibromohexamidine, hexamidine, chlorhexidine or polyaminopropyl biguanide),
9. i) aldehydes (such as glutaraldehyde),
10. j) amino acid derivatives (such as ethyl lauroylarginate HCl) and
11. k) organic halogen compounds (such as triclocarban, chloroacetamide, 3-iodo-2-propynyl butylcarbamate).

In addition, it is preferred that the cosmetic containing i) alkylresorcinol (e) and ii) cosmetic preservative (s) comprise at most 1% by weight of aromatic alcohols, more preferably 0.5% by weight of aromatic alcohols, with one especially preferred cosmetic contains no aromatic alcohols.

1. i) ein, zwei oder mehr Alkylresorcinole und
2. ii) ein, zwei oder mehr Kosmetikkonservierungsstoffe ausgewählt aus
   1. a) aromatischen Alkoholen,
   2. b) mehrwertigen aliphatischen Alkoholen,
   3. c) organischen Säuren oder deren Salzen oder Estern,
   4. d) Formaldehyd, Paraformaldehyd oder Formaldhydabspaltern,
   5. e) heterocyclischen Wirkstoffen,
   6. f) Phenolderivaten oder deren Salzen,
   7. g) quartären Ammoniumsalzen,
   8. h) Biguaniden und Amidinen,
   9. i) Aldehyden,
   10. j) Aminosäurederivaten und
   11. k) organischen Halogenverbindungen.

In a second aspect, the invention relates to a concentrate comprising

1. i) one, two or more alkylresorcinols and
2. ii) one, two or more cosmetic preservatives selected from
   1. a) aromatic alcohols,
   2. b) polyhydric aliphatic alcohols,
   3. c) organic acids or their salts or esters,
   4. d) formaldehyde, paraformaldehyde or formaldehydabspaltern,
   5. e) heterocyclic active substances,
   6. f) phenol derivatives or their salts,
   7. g) quaternary ammonium salts,
   8. h) biguanides and amidines,
   9. i) aldehydes,
   10. j) Amino acid derivatives and
   11. k) organic halogen compounds.

1. i) Alkylresorcinol ausgewählt aus 4-n-Butylresorcinol, 4-n-Hexylresorcinol und Mischungen davon und
2. ii) ein, zwei oder mehr aromatische Alkohole umfassen.

Preference is given to concentrates which

1. i) Alkylresorcinol selected from 4-n-butylresorcinol, 4-n-hexylresorcinol and mixtures thereof and
2. ii) one, two or more aromatic alcohols.

In a third aspect, the invention relates to the use of the concentrate according to the second aspect for the preservation of cosmetics. Preferred cosmetics using the inventive combination of i) alkylresorcinol (s) and ii) cosmetic preservative (s) according to the first aspect, in particular the concentrate according to the second aspect, are leave-on and rinse-off cosmetics.

The advantages of the invention will become apparent in particular from the following examples. Percentages are by weight unless otherwise specified.

Examples

Antimicrobial efficacy was demonstrated in an O / W cream, the composition and preparation of which are described below (Table 1). The indicated 4-butylresorcinol is 4-n-butylresorcinol: Table 1. INCI name trade name function parts by weight Phase A glycerin Glycerol 85% Humectants 2.3 sodium hydroxide Sodium hydroxide (45% aqueous solution) pH adjustment 0.2 Phase B Paraffinum liquidum mineral oil emollient 6.0 Dimethicone Dow Corning 200 Fluid emollient 5.0 stearic acid stearic acid consistency factor 4.0 cetyl alcohol Lanette 16 ¹⁾ consistency factor 3.0 Glyceryl stearate, PEG 30 stearate Arlacel 983 PW ²⁾ emulsifier 3.0 octyl palmitate Cegesoft C24 ¹⁾ emollient 1.5 water ad 100 1) Cognis 2) Croda

For the preparation, the separately prepared phases A and B were each heated to 80 ° C. Phase B was added slowly to phase A with stirring. It was homogenized and cooled to room temperature with gentle mixing to obtain the cream.

In germ count reduction tests, the killing effect of various drugs and drug combinations was semi-quantitatively tested (Table 2). In Test A, the synergistic increase in efficacy of phenoxyethanol by 4-butylresorcinol can be clearly seen. In contrast, test B shows the effect on phenylpropanol, and test C on benzyl alcohol. The low or undetectable intrinsic effectiveness of the 4-butylresorcinol used at the selected use concentrations (that is to say without the combination partner) can also be seen in these tests.

Each one week was tested to see whether the kill required for a successful test in the conservation load test (KoKo test, SM 021) was achieved. In the KoKo test, a sample is artificially contaminated six times at intervals of one week each and checked for microbial growth before contamination. Successful conservation shows no growth over the entire period. Table 2 germ S. aureus ATCC: 6538 E. coli ATCC: 11229 C. albicans ATCC: 10231 A. Brasilisis ATCC: 16404 hours 24 72 168 24 72 168 24 72 168 24 72 168 Cream (unpreserved, blank value) ++++ ++++ ++++ R R ++++ R ++++ ++++ R +++ +++ A 1 + 0.1% 4-butylresorcinol R +++ +++ ++++ 0 0 ++++ ++++ ++++ R +++ +++ 2 + 0.9% phenoxyethanol ++++ ++++ ++++ 0 0 0 R ++++ +++ R +++ 0 3 + 0.1% 4-butylresorcinol and 0.9% phenoxyethanol 0 0 0 0 0 0 ++ 0 0 ++ 0 0 B 1 + 0.75% phenylpropanol ++++ +++ + 0 0 0 ++++ +++ 0 +++ +++ ++ 2 + 0.0375% 4-butylresorcinol and 0.75% phenylpropanol 0 0 0 0 0 0 ++++ 0 0 + 0 0 C 1 + 0.05% 4-butylresorcinol ++++ ++++ ++++ R R ++++ R ++++ ++++ R +++ +++ 2 + 1.0% benzyl alcohol ++++ ++++ +++ 0 0 0 R ++++ ++++ R +++ 0 3 + 0.05% 4-butylresorcinol and 1.0% benzyl alcohol + 0 0 0 0 0 ++++ ++++ 0 +++ ++ 0

Table 3 shows by way of example the results for an unpreserved sample and for a sample with a combination according to the invention of 4-hexylresorcinol with phenylpropanol. The preservative effect of the combination is sufficient. Table 3 inoculation cycles 1 2 3 4 5 6 Cream, unpreserved +++ B, H, S +++ B, H, S / + 0.45% 3-phenylpropanol and 0.05% 4-hexylresorcinol - - - - - Legend: R lawn-like growth ++++ ~ 10 'cfu +++ ~ 10 'cfu ++ ~ 10 'cfu + ~ 10 'cfu 0 no growth / Test canceled B bacteria H yeast S Mould

Evidence that 4-butylresorcinol in a small amount does not lighten the skin

test materials

Lagerbedingungen

Raumtemperatur

Anwendungsbereich

Volare Unterarme

Anwendungsvolumen

bestimmt durch Wiegen der Menge des Testprodukts vor und nach dem Anwendungszeitraum. Das je Anwendung eingesetzte Volumen war die Menge, die auf eine Fingerspitze passte.

Anwendungsmodus

die Testmaterialien wurden von den Probanden zu Hause zwei bis dreimal täglich gemäß normalen Anwendungsbedingungen aufgetragen. Entsprechende Anweisungen wurden den Probanden mündlich gegeben, und die Anwendung wurde den Probanden am ersten Tag der Studie gezeigt.

The test products were used by the testing company as provided by the client (Table 4): Table 4. A Untreated control area (negative control) B B (placebo) C C (Verum 0.05%) D D (Verum 0.1%)

storage conditions

room temperature

scope of application

Volare forearms

application volume

determined by weighing the amount of the test product before and after the period of application. The volume used per application was the amount that fit on a fingertip.

application mode

the test materials were applied by subjects at home two to three times daily according to normal conditions of use. Appropriate instructions were given orally to the subjects and the application was shown to the subjects on the first day of the study.

Of the 22 subjects, two (2) were excluded during the study (N = 20).

methods

The study was conducted according to a protocol and was consistent with the main principles of GCP (Table 5). Table 5. Day 1 (baseline) Day 2 to 56 Day 29 Day 57 Consent after clarification X A / exclusion criteria X Subjective rating X Instrumentation (skin color) X X Check for compliance X Application of the test materials two to three times a day X * X * The first application of the test materials took place after instrument measurement at the site of the study.

Results of skin color measurements

The skin color was determined with a chromameter and the individual typological angle (ITA °) was calculated to evaluate the skin tan. A higher value for ITA ° corresponds to lighter skin.

Table 6 shows the mean values for ITA °, before (day 1) and after application of the product (57 days), the differences from the baseline (day 1) and the results of the comparisons of the treatments and the times with the t-test for affiliated samples. Table 6: Chromameter ITA - mean values, difference to baseline and comparisons of treatments to differences from baseline and times with raw data using t-test for connected samples (N = 20) Mean values comparison difference Times p-values Treatments p-values day 1 Day 57 to day 1 (baseline) Day 1 vs. Day 57 B C D A (untreated) 37.070 42.414 5,343 <0.001 * 0.539 ns 0.836 ns 0,550 ns B 36.904 41.865 4,961 <0.001 * - 0.493 ns 0.991 ns C 36.147 41.616 5.469 <0.001 * - - 0,348 ns D 36.231 41.200 4,970 <0.001 * - - - ns: Not significant *: significant, p ≤ 0.05

For all test areas, a significant increase in ITA ° was found at the end of the study on day 57 compared to the baseline values (day 1).

The comparison of the treatments showed no significant differences (difference to the baseline) for all changes of ITA °.

The subjective evaluation of the skin color by the subjects themselves showed no significant differences between the treatments.

Evidence that 4-Hexylresorcinol in a small amount does not lighten the skin

test materials

The test products were used by the testing company as provided by the client (Table 7): Table 7. A Verum or placebo B Verum or placebo C Untreated control area

The other conditions were the same as in the study of 4-butylresorcinol. Of the 22 subjects, six (6) were excluded during the study (N = 16).

methods

The study was conducted according to a protocol and was consistent with the main principles of GCP (Table 8). Table 8. 1 2 to 28 29 30-56 57 Application of the test materials two to three times a day X * X X X Check for compliance X Chromametermessung X X Subjective rating X * The first application of the test materials took place after instrument measurement at the site of the study.

Results of skin color measurements

The skin color was determined with a chromameter and the individual typological angle (ITA °) was calculated to evaluate the skin tan. A higher value for ITA ° corresponds to lighter skin.

Table 9 shows the mean values for ITA °, measured at both times, the differences from the baseline (day 1) and the results of comparisons of products and times with the t-test for connected samples. Table 9: Chromameter ITA (N = 16) raw Data Difference to day 1 (baseline) means p-values using t-test for connected samples means p-values using t-test for connected samples day 1 Day 57 Day 1 vs day 57 Day 57 A vs. B A 33.88 40.28 <0.001 * 6.40 0.408 ns B 33.89 40.76 <0.001 * 6.87 C 33,68 39.38 - 5.71 - ns: Not significant *: significant, p ≤ 0.05

The comparison of the values for ITA ° before (day 1) and after (day 57) application of the products showed a significant increase after application of the two test products A and B. No significant difference was found between the test products A and B for changes in ITA ( Difference to the baseline).

The subjective evaluation of the skin color by the subjects themselves showed no significant differences between the treatments.

This proves that the application of the cosmetic products used causes a significant reduction in skin pigmentation. However, no significant difference was found between the tested products. Because the cream (placebo), which does not contain an alkylresorcinol, also showed this effect, it has been proven that the reduction in skin pigmentation was caused by a reduction in the UV radiation during the course of the study.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008041971 A1 [0004]
• WO 2008/058680 [0005]
• US 2009/0148391 A1 [0006]
• EP 1374849 A1 [0007]
• GB 0910629 [0008]
• EP 2149364 A1 [0009]
• DE 102013217244 A1 [0010]

Claims (11)

Use of one, two or more alkylresorcinols to improve the antimicrobial efficacy of one, two or more cosmetic preservatives, wherein the amount of alkylresorcinol is at most 0.2% by weight, based on the weight of the cosmetic. Use after Claim 1 , characterized in that the amount of alkylresorcinol 0.01 to 0.15 wt .-%, preferably 0.02 to 0.12 wt .-%, in particular 0.03 to 0.1 wt .-%, based on the weight of the cosmetic. Use after Claim 1 or 2 , characterized in that the alkylresorcinol is a 4-alkylresorcinol. Use according to any one of the preceding claims, characterized in that the alkyl group of the alkylresorcinol is selected from linear or branched alkyl groups, the alkyl group preferably being a linear alkyl group. Use according to one of the preceding claims, characterized in that the alkyl group is a C ₂ - to C ₁₀ -alkyl group, preferably a C ₃ - to C ₈ -alkyl group, such as a butyl or hexyl group, wherein the alkyl group is in particular a butyl group , Use according to any one of the preceding claims, characterized in that the alkylresorcinol is 4-n-butylresorcinol. Use according to one of the preceding claims, characterized in that the cosmetic preservative is selected from a) aromatic alcohols, such as benzyl alcohol, phenoxyethanol, phenylethyl alcohol, phenoxyisopropanol, dichlorobenzyl alcohol and phenylpropanol), b) polyhydric aliphatic alcohols (such as 1,2-pentanediol, chlorphenesin, 1,2-hexanediol, 1,2-octanediol and 1,3-propanediol), c) organic acids (such as benzoic acid, sorbic acid, salicylic acid, anisic acid, dehydroacetic acid, 4-hydroxybenzoic acid) or their salts or esters, d) formaldehyde, paraformaldehyde or formaldehyde-releasing agents (such as methenamine, DMDM-hydantoin, diazolidinylurea, imidazolidinylurea, sodium hydroxymethylglycinate, 7-ethylbicyclooxazolidine, benzylhemiformal, hexetidine, quaternium-15, Bronidox and bronopol), e) heterocyclic agents (such as methylchloroisothiazolinone, methylisothiazolinone, pyrithione-zinc, piroctone Olamine or climbazole), f) phenol derivatives (such as chlorocresol, T riclosan, chloroxylenol, bromochlorophene, o-cymene-5-ol, chlorophene, 2-hydroxybiphenyl) or their salts, g) quaternary ammonium salts (such as alkyl (C _12-22 ) trimethylammonium bromide and chloride, benzalkonium chloride, benzethonium chlorides, octenidine dihydrochloride), h ) Biguanides and amidines (such as dibromohexamidine, hexamidine, chlorhexidine or polyaminopropyl biguanide), i) aldehydes (such as glutaraldehyde), j) amino acid derivatives (such as ethyl lauroylarginate HCl) and k) organic halogen compounds (such as triclocarban, chloroacetamide, 3-iodo-2-propynyl butyl carbamate ). Use according to one of the preceding claims, characterized in that the cosmetic comprises at most 1% by weight of aromatic alcohols. Concentrate which comprises i) one, two or more alkylresorcinols and ii) one, two or more cosmetic preservatives selected from a) aromatic alcohols, b) polyhydric aliphatic alcohols, c) organic acids or their salts or esters, d) formaldehyde, paraformaldehyde or Formaldehyde scavengers, e) heterocyclic active compounds, f) phenol derivatives or their salts, g) quaternary ammonium salts, h) biguanides and amidines, i) aldehydes, j) amino acid derivatives and k) organic halogen compounds. Concentrate after Claim 9 , characterized in that it comprises i) alkylresorcinol selected from 4-n-butylresorcinol, 4-n-hexylresorcinol and mixtures thereof and ii) one, two or more aromatic alcohols. Use of the concentrate according to Claim 9 or 10 for the preservation of cosmetics, preferably leave-on or rinse-off cosmetics.