Transparent, aqueous sunscreen containing pullulan and 2-phenylbenzimidazole-5-sulfonic acid salts

Abstract

Water-based cosmetic preparation containing a) 0.2 to 10% by weight of 2-phenylbenzimidazole-5-sulfonic acid salts, b) 0.1 to 5% by weight of pullulan, the weight percentages being based on the total weight of the water-based preparation.

Description

[0001] Beiersdorf Aktiengesellschaft

[0002] Hamburg

[0003] Description

[0004] New, transparent, water-based sunscreen

[0005] The present invention relates to a water-based cosmetic preparation containing a) 0.2 to 10 wt% 2-phenylbenzimidazole-5-sulfonic acid salts,

[0006] b) 0.1 to 5% by weight of pullulan, where the weights refer to the total weight of the water-based preparation.

[0007] The trend away from a pale complexion and towards a "healthy, sporty tan" has been unbroken for years. To achieve this, people expose their skin to sunlight, as this stimulates pigment production in the form of melanin. However, the ultraviolet radiation in sunlight also has a damaging effect on the skin. In addition to acute damage (sunburn), long-term damage such as an increased risk of developing skin cancer occurs with excessive exposure to UVB light (wavelength: 280-320 nm). Furthermore, excessive exposure to UVB and UVA radiation (wavelength: 320-400 nm) leads to a weakening of the elastic and collagen fibers of the connective tissue. This results in numerous phototoxic and photoallergic reactions and premature skin aging.

[0008] To protect the skin, a number of sunscreen filters have been developed that can be used in cosmetic preparations. These UVA and UVB filters are listed in positive lists in most industrialized countries, such as Annex 7 of the Cosmetics Regulation.

[0009] However, the large number of commercially available sunscreens should not obscure the fact that these state-of-the-art preparations have a number of disadvantages.

[0010] Most cosmetic sunscreens are offered in the form of emulsions, oils, or ethanolic solutions. The fact that there are practically no purely aqueous sunscreens is primarily due to the fact that most UV filter substances are either soluble in ethanol or lipids. The lack of sufficient water-soluble UV filters for balanced and high UVA and UVB protection presents a major initial hurdle for experts in the development of aqueous products.

[0011] For aqueous systems, practically only UV filter substances based on sulfonic acids are suitable. Besides benzophenone-4 (IUPAC: 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid), these include in particular 2-phenylbenzimidazole-5-sulfonic acid, terephthalidene dicamphor sulfonic acid (INCI: Terephthalidiene Dicamphor Sulfonic Acid), and disodium phenylbenzimidazole sulfonic acid (INCI: Disodium Phenyl Dibenzimidazole Tetrasulfonate).

[0012] However, aqueous preparations containing these UV filters have a number of disadvantages: According to current technology, high sun protection factors cannot be achieved with such aqueous systems. They typically remain well below SPF 20.

[0013] The object of the present invention was therefore to develop a water-based cosmetic sunscreen that offers high UV protection (i.e., a sun protection factor of at least 20 and preferably a sun protection factor of 30). This water-based sunscreen should ideally be transparent (i.e., clear and see-through) and, although thin, should spread well in larger quantities on the skin without immediately running off upon application. Furthermore, the preparation should be free of polyacrylates and polyacrylic acid copolymers.

[0014] Aqueous cosmetic sunscreens also have the disadvantage of being colorless, like water, and are therefore often tinted for safety reasons. Furthermore, the even distribution of tinted preparations on the skin is easier to control than with colorless preparations. However, the water-soluble dyes used for this purpose are not always compatible with the other ingredients in the preparation. In addition, some consumers have reservations about the use of dyes.

[0015] The object of the present invention was therefore to develop a transparent aqueous sunscreen that is already colored without the addition of dyes. Aqueous cosmetic sunscreens have the problem that visible precipitation (crystal or flake formation) often occurs when stored at colder ambient temperatures. These preparations are not particularly cold-stable.

[0016] The object of the present invention was therefore to develop an aqueous cosmetic sunscreen that remains transparent and clear even at storage temperatures below 0 °C and preferably below -10 °C, without any separation from the preparation.

[0017] This task is surprisingly solved by a water-based cosmetic preparation containing

[0018] a) 0.2 to 10 wt% 2-phenylbenzimidazole-5-sulfonic acid salts,

[0019] b) 0.1 to 5% by weight of pullulan, where the weights refer to the total weight of the water-based preparation.

[0020] According to the invention, it is preferred if the 2-phenylbenzimidazole-5-sulfonic acid salts are contained in the water-based preparation in an amount of 0.5 to 4% by weight, based on the total weight of the preparation.

[0021] Advantageous embodiments of the present invention are characterized in that the pullulan has a molecular weight Mn of 50000 to 100000.

[0022] According to the invention, it is advantageous if the water-based preparation is transparent. A preparation is considered "transparent" or "clear" within the meaning of the present invention if it is possible to see through a disposable cuvette (Brand company, 2.5 ml, wavelength range: 220 nm–900 nm) filled with the preparation according to the invention with the naked eye in daylight. Text (Arial font, size 8) located directly behind the disposable cuvette must be clearly visible and legible.

[0023] It is advantageous in the sense of the present invention if the preparation is colored yellow, i.e., has a yellowish color similar to that of clear apple juice.

[0024] According to the invention, it is preferred if the preparation is free of dyes.

[0025] If a balanced protection against IIV-A and UV-B radiation is to be achieved, it is advantageous according to the invention to use additional UV filters. Specifically, it is advantageous if the water-based preparation contains salts of 3,3'-(1,4-phenylenedimethylene)bis[7,7-dimethyl-2-oxo-bicyclo[2.2.1]heptane-1-methanesulfonic acid] (INCI: Terephthalidiene Dicamphor Sulfonic Acid) in an amount of 0.5 to 3.5% by weight, based on the total weight of the water-based preparation. An amount of 1 to 3% by weight, based on the total weight of the water-based preparation, is preferred according to the invention.

[0026] An advantageous alternative according to the invention is characterized in that the water-based preparation contains the disodium salt of 2,2'-(biphenyl-4,4'-diyldiethene-2,1-diyl)dibenzenesulfonic acid (INCI: Disodium Phenyl Dibenzimidazole Tetrasulfonate) in an amount of 0.5 to 3.5% by weight, based on the total weight of the water-based preparation. An amount of 0.5 to 3.0% by weight, based on the total weight of the water-based preparation, is preferred according to the invention.

[0027] According to the invention, it is particularly preferred if the preparation contains a combination of both UV filters (Terephthalidiene Dicamphor Sulfonic Acid and Disodium Phenyl Dibenzimidazole Tetrasulfonate).

[0028] Preferred embodiments of the present invention are further characterized in that the sulfonic acid salts are a mixture of triethanolamine and sodium salts.

[0029] Such a mixture is obtained, in particular, by neutralizing (at least partially) the sulfonic acids of the three sulfonic acid groups of UV filters (2-phenylbenzimidazole-5-sulfonic acid, terephthalide dicamphor sulfonic acid, and disodium phenyl dibenzimidazole tetrasulfonate) with triethanolamine and sodium hydroxide solution. Particularly high sun protection factors can be achieved with formulations neutralized in this way.

[0030] It is advantageous within the meaning of the present invention if the water-based preparation contains water in an amount of at least 60% by weight, based on the total weight of the water-based preparation. A water quantity of at least 70% by weight, based on the total weight of the water-based preparation, is preferred according to the invention.

[0031] Furthermore, according to the invention, it is advantageous if the water-based preparation contains ethylhexylglycerin in an amount of at least 0.05 to 1.0% by weight, based on the total weight of the water-based preparation. It is also advantageous according to the invention if the water-based preparation contains phenoxyethanol in an amount of at least 0.05 to 1.0% by weight, based on the total weight of the water-based preparation.

[0032] Furthermore, it is advantageous according to the present invention if the water-based preparation contains one or more alkanediols from the group consisting of 1,2-pentanediol, 1,2-hexanediol, 1,2-octanediol, 1,2-decanediol, and 2-methyl-1,3-propanediol. The use of 1,2-hexanediol is preferred according to the invention.

[0033] If, for various reasons, it is desirable for the preparation according to the invention to have a higher viscosity, it has proven advantageous according to the invention if the water-based preparation contains one or more gums (INGI: Gum).

[0034] According to the invention, it is preferred if the water-based preparation contains one or more gums selected from the group of compounds xanthan gum (INCI: Xanthan Gum), dehydroxanthan gum (INCI: Dehydroxanthan Gum), sclerotium gum (INCI: Sclerotium Gum) and / or carob gum (INCI: Ceratonia Siliqua Gum).

[0035] To increase the viscosity, the water-based preparation can also advantageously contain hydroxypropylguar according to the invention.

[0036] Another advantageous component of the water-based preparation according to the invention is EDTA.

[0037] The water-based preparation according to the invention can, advantageously according to the invention, be used in two different forms: as an aqueous preparation, in particular as an aqueous spray or gel.

[0038] Therefore, according to the invention, it is advantageous if the water-based preparation is presented as an aqueous spray or gel.

[0039] According to the invention, it is preferred if the preparation is free of polyethylene glycol, polyethylene glycol ethers and polyethylene glycol esters (so-called PEG derivatives), polyacrylates and polyacrylic acid copolymers.

[0040] Furthermore, according to the invention, it is advantageous if the preparation is free of polymers based on polyvinylpyrrolidone (PVP). In particular, it is preferred according to the invention if the preparation is free of parabens, methylisothiazolinone, chloromethylisothiazolinone, and DMDM ​​hydantoin.

[0041] Furthermore, according to the invention, it can be advantageous if the preparation contains one or more active ingredients selected from the group of compounds alpha-lipoic acid, folic acid, phytoene, D-biotin, coenzyme Q10, alpha-glucosylrutin, carnitine, carnosine, natural and / or synthetic isoflavonoids, flavonoids, creatine, creatinine, taurine, β-alanine, panthenol, magnolol, honokiol, tocopheryl acetate, dihydroxyacetone; 8-hexadecene-1,16-dicarboxylic acid, glyceryl glycose, (2-hydroxyethyl)urea, vitamin E or its derivatives, hyaluronic acid and / or its salts, / V-[4-(2,4-dihydroxyphenyl)-1,3-thiazol-2-yl]-2-methylpropanamide (INCI: Isobutylamido Thiazolyl Resorcinol) and / or licochalcone A. Comparative experiments / execution example

[0042]

[0043] The L*a*b values ​​were determined for both preparations.

[0044] Formula 1: L= 100; a= -13.7; b = 37.6

[0045] Formula 2: L= 100; a= -23.9; b = 65.8

[0046] The determination of the L*a*b color space is standardized under EN ISO / IEC 11664-4. The L value describes the brightness, where L=100 means white and L=0 marks black; "a" describes the green / red values, where negative values ​​indicate a green tint and positive values ​​a red tint; "b" describes the blue / yellow values, where negative values ​​indicate a blue tint and positive values ​​a yellow tint.

[0047] Formula 2 according to the invention is therefore significantly more yellow than Formula 1. This is surprising to those skilled in the art, since both film-forming agents are white powders and no difference in color would be expected. The film-forming agent used in Formula 1 (hydrolyzed corn starch) confirms the lack of influence on the color of the formulation, as expected by those skilled in the art. Both formulas are equally transparent.

[0048] Storage test:

[0049] Both preparations were stored at -10 °C for 30 days and then visually assessed.

[0050] Result:

[0051] In formula 2, virtually no crystals form after 30 days at a storage temperature of -10 °C. Storing formula 1 for 30 days at -10 °C results in the irreversible formation of a large number of light filter crystals. Example formulations

[0052] The following examples are intended to illustrate the present invention without limiting it. Unless otherwise stated, all quantities, proportions, and percentages are based on the weight and total quantity or total weight of the preparations.

[0053]

Claims

Patent claims 1. Water-based cosmetic preparation containing a) 0.2 to 10 wt% 2-phenylbenzimidazole-5-sulfonic acid salts, b) 0.1 to 5% by weight of pullulan, where the weights refer to the total weight of the water-based preparation.

2. Cosmetic preparation according to claim 1, characterized in that the pullulan has a molecular weight Mn of 50000 to 100000.

3. Cosmetic preparation according to one of the preceding claims, characterized in that the preparation is water-based and transparent.

4. Cosmetic preparation according to one of the preceding claims, characterized in that the preparation is colored yellow.

5. Cosmetic preparation according to one of the preceding claims, characterized in that the preparation is free of dyes.

6. Cosmetic preparation according to one of the preceding claims, characterized in that the water-based preparation contains salts of 3,3'-(1,4-phenylenedimethylene)bis[7,7-dimethyl-2-oxo-bicyclo[2.2.1]heptane-1-methanesulfonic acid] (INCI: Terephtalydiene Dicamphor Sulfonic Acid) in an amount of 1.0 to 3.5% by weight, based on the total weight of the water-based preparation.

7. Cosmetic preparation according to one of the preceding claims, characterized in that the water-based preparation contains the disodium salt of 2,2'-(biphenyl-4,4'-diyldiethene-2,1-diyl)dibenzenesulfonic acid (INGI: Disodium Phenyl Dibenzimidazole Tetrasulfonate) in an amount of 0.5 to 3.5 wt%, based on the total weight of the water-based preparation.

8. Cosmetic preparation according to one of the preceding claims, characterized in that the sulfonic acid salts are a mixture of triethanolamine and sodium salts.

9. Cosmetic preparation according to one of the preceding claims, characterized in that the water-based preparation contains water in an amount of at least 60% by weight, based on the total weight of the water-based preparation.

10. Cosmetic preparation according to one of the preceding claims, characterized in that the water-based preparation contains ethylhexylglycerin in an amount of at least 0.05 to 1.0 wt%, based on the total weight of the water-based preparation.

11. Cosmetic preparation according to one of the preceding claims, characterized in that the water-based preparation contains phenoxyethanol in an amount contains at least 0.05 to 1.0% by weight, based on the total weight of the water-based preparation.

12. Cosmetic preparation according to one of the preceding claims, characterized in that the water-based preparation contains one or more alkanediols from the group consisting of the compounds 1,2-pentanediol, 1,2-hexanediol, 1,2-octanediol, 1,2-decanediol, 2-methyl-1,3-propanediol.

13. Cosmetic preparation according to one of the preceding claims, characterized in that the water-based preparation contains one or more gums (INCI: Gum).

14. Cosmetic preparation according to one of the preceding claims, characterized in that the water-based preparation comprises one or more gums selected from the group consisting of the compounds xanthan gum (INCI: Xanthan Gum), dehydroxanthan gum (INCI: Dehydroxanthan Gum), sclerotium gum (INCI: contains sclerotium gum) and / or carob gum (INCI: Ceratonia Siliqua Gum).

15. A cosmetic preparation according to any one of the preceding claims, characterized in that the water-based preparation contains hydroxypropylguar.

16. A cosmetic preparation according to any one of the preceding claims, characterized in that the water-based preparation contains EDTA.

17. Cosmetic preparation according to one of the preceding claims, characterized in that the preparation is water-based and is presented as an aqueous spray or gel.

18. Cosmetic preparation according to one of the preceding claims, characterized in that the preparation is free of polyethylene glycol, polyethylene glycol ethers and polyethylene glycol esters (so-called PEG derivatives), polyacrylates and polyacrylic acid copolymers.

19. Cosmetic preparation according to one of the preceding claims, characterized in that the preparation is free of polymers based on polyvinylpyrrolidone (PVP).

20. Cosmetic preparation according to one of the preceding claims, characterized in that the preparation is free from parabens, methylisothiazolinone, chloromethylisothiazolinone and DMDM ​​hydantoin.

21. Cosmetic preparation according to one of the preceding claims, characterized in that the preparation contains one or more active ingredients selected from the group consisting of the following compounds: alpha-lipoic acid, folic acid, phytoene, D-biotin, coenzyme Q10, alpha-glucosylrutin, carnitine, carnosine, natural and / or synthetic isoflavonoids, flavonoids, creatine, creatinine, taurine, β-alanine, panthenol, magnolol, honokiol, tocopheryl acetate, dihydroxyacetone; 8-hexadecene-1,16-dicarboxylic acid, glyceryl glycose, (2-Hydroxyethyl)urea, vitamin E or its derivatives, hyaluronic acid and / or its salts, / V-[4-(2,4-dihydroxyphenyl)-1,3-thiazol-2-yl]-2-methylpropanamide (INCI: contains isobutylamido thiazolyl resorcinol) and / or licochalcone A.

22. Transparent packaging material containing a preparation according to one of the preceding claims.

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