MXPA98006282A - Cosmetic composition filter of the - Google Patents

Abstract

The invention relates to a cosmetic light filtering composition for protecting human skin or human hair from ultraviolet radiation containing at least one compound of formula I wherein R 1 represents a linear or branched alkyl chain of C 1-8, and R2 and R3 each represent, independently, a straight or branched chain alkyl of C1

Description

COSMETIC COMPOSITION FILTER OF THE LIGHT Field of the Invention The invention relates to a light filtering composition, cosmetic, to the use of the cosmetic light filtering composition for the protection of human skin and human hair against ultraviolet radiation of wavelengths between about 280 and 400 nm , compounds contained in the composition and the use of these compounds as UV filters.

Anthesis of the Invention.

It is known that sunlight accelerates the aging of the skin and still leads to skin cancer, these unwanted effects being caused by UV radiation.

Description of the invention.

It has also been found that the compounds of the formula I REP: 27958 wherein R represents a linear or branched alkyl chain of C. β, and R2 and R each represent, independently, a straight or branched chain alkyl of C1. a are excellent UV filters with respect to compability and stability with the skin (light, heat, humidity); They constitute a strong contribution to the UV protection of the skin and therefore cause a delay in the aging of the skin. In particular, these UV filters also have significant photostability.

It has also been found that the compounds of formula I have their absorption maximum between those of UV filters A, such as, for example, 4-tert-but-il'-4'-methoxydibenzoylmethane and those of UV filters B and especially and surprisingly they increase the protective effect of UV filters B, that is substances that absorb mainly the UV-B radiation producing erythema in the region of about 290 to about 320 nm, although the maximum absorption of the compound of formula I does not It is found in this region, but in the region of around 320 to 340 nm, that is between the maximum of UVA and UVB radiation.

The only types of UV filters available for cosmetic use that also absorb in these regions are the benzophenones and menthyl anthranilate. Many formulators do not use them for several reasons, for example very low extraction compared to the compounds of formula I.

The alkoxyanilinomethylene propandioic acid esters of the formula I are known from US Pat. No. 3,079,366 and from W.O. Kermack, N.E. Storey, J. Chem. Soc. 607 (1950); T.

Takahashi, S. Senda, J. Pharm. Soc. Jpn., 71, 1112 (1952). Esters of methoxy-ethoxy- and butoxy-anilino-methylene-propandioic have been specifically described. But nothing has been described about the use of these compounds for cosmetic purposes, especially for the use of these compounds in skin care or hair care.

A UV filter must show a high solubility in cosmetic solvent in order to be formulated in a reasonable concentration. For example, a 6% UV filter content in a conventional oil / water emulsion having a water content of 70% requires a solubility of up to 20% in the oil phase. Surprisingly it has been found that the compounds of formula I show solubility of up to 20% in many cosmetic solvents such as capric caprylic glyceride, propylene glycol dicaprylate / dicaprate, C12_15 alkyl benzoate, propylene glycol monoisoterate, di isopropyladipate.

Objects of the present invention are, therefore, new compounds of formula I, light filtration preparations for cosmetic purposes containing at least one of the compounds of formula I above, preferably in combination with at least one filter agent B of UV and at least one UV filter agent A, and the use of compounds of formula I as light filtering agents, especially for cosmetic purposes.

Thus, the present invention provides a cosmetic light filtering composition for protecting human skin or human hair against ultraviolet radiation containing in a cosmetically acceptable vehicle at least one compound of formula I wherein R represents a linear or branched alkyl chain of Cx-8, R and R each represent, independently, a linear or branched alkyl chain of C1_s.

The term "linear or branched alkyl chain of C _-8" refers to groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tertiary butyl, pentyl, heptyl, 2-ethyl-hexyl and the like.

Preferred are compounds wherein R and R3 each represent, independently, methyl, ethyl, pentyl or 2-ethylhexyl.

The group R is preferably methyl, ethyl or n-butyl.

Thus, the following compounds are preferred: compounds wherein R1, Rz and R3 are methyl (Example 1) or ethyl (Example 4); or R1 is ethyl and R and R3 are methyl (Example 2) or 2-ethylhexyl (Example 6); or R1 is n-butyl and R2 and R3 are methyl, (Example 3) or ethyl (Example 5).

The most preferred is a compound according to example 4 wherein R1, R2 and R3 are yyl.

The cosmetic light filtering composition preferably comprises 0.1 to 10% by weight, more preferably 0.5 to 5% by weight, of the compound (s) of formula I, in particular 1 to 3 % by weight of the compound (s) of formula I.

The cosmetic light filtering composition may in addition comprise at least one UV-B filter agent with an absorption maximum of about 300 to 320 nm and at least one UV-A filter agent with a maximum absorption a > 340 nm, especially between 340 and 360 nm, particularly a UV-A filter agent having an absorption maximum at 356 n. Specifically, this UV-A filter agent is 4-tert-butyl-4'-methoxydibenzoylmethane. In general, the UV-A filter agent can be selected from the group consisting of 2-metyl-dibenzoylmethane, 4-methyl-dibenzoyl-methane, 4-tert-butyl idibenzoyl-methane, 2,4-dimethyl-dibenzoylmethane, 2,5- dimethyl-ildibenzoylmethane, 4,4'-diisopropyldibenzoylmethane, 4-tert-butyl-4'-methoxydibenzoylmethane, 2-methyl-5-isopro-4'-methoxydibenzoylmethane, 2-methyl-5-tert-butyl-4'-methoxydibenzoylmethane, 2, 4-dimethyl-'-methoxydibenzoylmethane 2,6-dimethyl-4-tert-butyl 4'-methoxydibenzoylmethane and terephtaliden dicanfor sulphonic acid The UV-B filter agent is at least one of the group consisting of cyanamates, salicylates, benzophenones, diphenylacrylates, triazines, camfor derivatives, polymeric UV absorbers especially those described in U.S. patent 5 403 944 and microfine pigments. In particular, the UV-B filter agent is at least one of the group consisting of pigmentary metallic oxides of cerium, iron, titanium, zinc or zirconium, especially of titanium or zinc and polymers with a hydrocarbon structure or siloxane structure comprising at least one ultraviolet light absorption group.

The cosmetic light filtering compositions of the compounds of formula I are useful for protecting human skin or human hair against ultraviolet radiation.

The following compounds of formula I are new: 2 - (4-heptoxy-anilinomet ilen) -propanedioic acid diethyl ester, 2- (4-methoxyanilinomethylene) -propanedioic acid dimethyl ester, 2- (2-dimethyl ester) 4-ethoxy-anilinomet ilen) -propanedioic acid 2- (4 -propoxy-anilinomethylene) -propanedioic acid dimethyl ester 2- (4-butoxy-anilinomethylene) -propanedioic acid dimethyl ester 2 - (4-dimethyl ester -pentoxy-anilinomethylene) -propanedioic acid, 2- (4-hexoxy-anilinomethylene) -propanedioic acid dimethyl ester, 2- (4-ethoxy-anilinomethylene) -propanedioic acid dipentyl ester, 2- (2-ethyl ester) pentylester 4-Ethoxy -anilinomethylene) -propanedioic acid, 2- (4-ethoxy-anilinomethyl) -propanedioic acid 2- (4-ethoxy-anilinomet) 2- (4-ethoxy-anilinomet) -2- ethylhexyl ester ilen) -propandioic.

Each of these can be used as a UV filter, especially for cosmetic purposes as has been said before. In this regard the following are of specific interest: 2- (4-ethoxy-anilinomet ilen) -propandioic acid dipentyl ester, 2- (4-ethoxy-anilinomethylene) -propanedioic acid ethyl ester, 2- -ethyl 2- (4-ethoxy-anilinomethylene) -propandioic acid ethyl ester and 2- (4-ethoxy-anilinomethylene) -propanedioic acid ethyl ester 2-ethyl-2-ethyl ester.

The compounds represented by the formula I (known and new compounds) are conveniently prepared with conventional methods as described in US 3,079,366 and which can be briefly described as follows: Reaction of an aniline derivative (C-L-Cg alkoxyaniline) with the malono derivative appropriately alkoxyalkylene substituted with or without solvent.

As the usual cosmetically acceptable vehicle for light filtering agents within the scope of the present invention, any conventional preparation corresponding to the cosmetic requirements can be used, for example creams, lotions, emulsions, ointments, gels, solutions, sprays, bars and milks.; see, for example, Kosmetik, Entwicklung, Herstellung and Anwendung Kosmetischer Mittel, ed. Wilfried Umbach, Georg Thieme Vertrag Stuttgart - New York 1988; Sunscreens, Development, Evolution and Regulatory Aspects, ed. N.Y. Lowe, N.A. Shaat, Marcel Decker, Inc. New York Basel, 1990.

With respect to lipophilicity, the compounds of formula I can be incorporated in cosmetic compositions containing oil and containing fat.

With respect to lipophilicity the new compounds meet the criteria required in the present case, that is, a solubility in cosmetic solvents, such as, for example, Miglyol 812N (capric caprylic triglyceride), Miglyol 840 (propylene glycol dicaprate dicaprylate), Finsolv TN (c-2-s) alkyl benzoate 'Prisorine 2034 (propylene glycol monoisosterate) or Crodamol DA (diisopropyladipate).

The compound of Example 4 is especially preferred particularly in the aspect just mentioned.

The appropriate cosmetic filtering formulations take the form of an oil, a lotion, a gel, a solid stick, an emulsion, for example, cream, milk or a vesicular dispersion of ionic or nonionic anionic lipids, an aerosol, a spray, a foam, a powder, a shampoo, a conditioner or hair spray or a make-up or the like.

In the case of preparing a cosmetic formulation for the protection of human hair with at least one compound of formula I the appropriate formulations are shampoos, conditioners, lotions, gels, emulsions, dispersions, lacquers or the like. The preparation of all these formulations is well known to the person skilled in the art.

The usual solvents known to those skilled in the art can be used for the preparation of these forms, for example oils, waxes, alcohols, polyols. Preferred agents are fatty acids, esters, fatty alcohols, but ethanol, isopropanol, propylene glycol, glycerin or the like are also useful.

The cosmetic formulations may contain other adjuvants, for example other solvents, thickeners, emollients, emulsifiers, humectants, tensides, preservatives, defoamers, fragrances, oils, waxes, lower polyols and monohydric alcohols, propellants, silicones, dyes and pigments or the like.

An important advantage of the new light filtering composition or of the compounds of formula I is that the person skilled in the art is completely free in the choice of the material used for the filtration of UV-B and UV-A radiation. as already indicated before. But for UV-A filtration the most preferred UV-A filter agent is 4-tert-butyl-4'-methoxydibenzoylmethane, this is especially used in combination with 2- (4-ethoxy-anilinomethylene) -propanedioic acid diethyl ester. .

Other advantages, features and details are described in the following examples.

EXAMPLE 1 Dimethyl acid 2- (4-methoxy-anilinomet ilen) -propanedioic acid ester To a solution of 12.3 g (0.1 mol) of p-anisidine in 50 ml of ethanol, a solution of 17.4 g (0.1 mol) of methoxy was added dropwise with stirring at room temperature. -met dimethyl ilenmalonate in 70 ml of ethanol. After an additional hour of stirring at this temperature the reaction mixture was cooled with an ice bath and the product crystallized spontaneously. The crude solid material was isolated by filtration and washed with ethanol and gave 12.9 g of the title product which is a white flux solid at 89-91 ° C, UV 328 nm (E = 899). 2 - (4-Ethoxyanilinomethylene) -propanedioic acid dimethyl ester The same preparation as Example 1 where an equivalent of p-phenetidine was used in place of p-anisidine.

There was obtained 19.8 g of the title compound which is a white fluxing solid at 66-67 ° C, UV 328 nm (E = 879).

EXAMPLE 3 Dimethyl acid 2- (4-butoxy-anilinomet ilen) -propanedioic acid ester a) Preparation of 2- (4-hydroxyanilinomethylene) -propanedioic acid dimethyl ester.

To a solution of 16.4 g (0.15 mol) of 4-aminophenol in 100 ml of ethanol was added dropwise, at room temperature, a solution of 26.1 g (0.15 mol) of dimethyl methoxymethylenemalonate. in 70 ml of ethanol. After 10 more minutes of stirring at this temperature the crude solid material was isolated by filtration and washed with ethanol and gave 34.3 g of a white solid which was then used without further purification. b) To a mixture of 7 g (28 mMol) of 2- (4-hydroxyanilinomethylene) -propanedioic acid dimethyl ester, 3.9 g (28 mMol) of potassium carbonate in 50 ml of dimethylformamide were added dropwise. , with stirring and at room temperature, 7.3 g (28 mMol) of butyl iodide. The reaction mixture was heated at 80 ° C for 24 hours. The reaction mixture was then poured into 50 ml of water and extracted three times with ethyl acetate. The organic phase was washed with a sodium hydroxide solution (15%) and then with water, dried and evaporated and gave 4.5 g of the title compound which is a white fluxing solid at 46-47 ° C, UV 328 nm (E = 685).

EXAMPLE 4 2- (4-ethoxy-anilino et ilen) -propandioic acid diethyl ester The preparation was the same as in Example 1, but an equivalent of p-phenetidine was used in place of p-anisidine and an equivalent of diethyl ethoxymethylenemalnonate was used in place of dimethylmethoxymethylenemalonate. Ethanol was replaced with hexane. 21 g of the title compound was obtained which is a white fluxing solid at 55-56 ° C, UV 329 nm (E = 802).

EXAMPLE 5 2- (4-Butoxy-anilinomet ilen) -propanedioic acid diethyl ester The preparation was the same as in Example 3, but an equivalent of diethyl ethoxymethylenemalnonate was used in place of dimethylmethoxymethylenemalonate. 3.1 g of the title compound was obtained which is a white fluxing solid at 54-55 ° C, UV 329 nm (E = 714).

EXAMPLE $ 2- (4-Ethoxy-anilinomethylene) -propanedioic acid 2-ethylhexyl ester and 2-ethylhexyl ester of 2- (4-ethoxy-anilinomet ilen) -propanedioic acid ethyl ester A mixture of 18.4 g (60 mMol) of 2- (4-ethoxy-anilinomethylene) -propanedioic acid diethyl ester, 430 mg of titanium (IV) isopropoxide in 70 ml of 2-ethyl-hexanol was stirred at 150 ° C for 4 hours. The reaction mixture was concentrated under reduced pressure (80 ° C, 6 mbar) to obtain a yellow oil. This oil was dissolved in 100 ml of ethyl acetate and 5 ml of water, stirred for 10 minutes and dried over anhydrous magnesium sulfate. The squamous suspension was filtered and concentrated under reduced pressure and gave 26.8 g of a yellow oil. The two products of the epigraph were isolated by flash chromatography using hexane: ethyl acetate 10: 1 as eluent. 23.6 g of di-2-ethylhexyl ester of 2- (4-ethoxyanilinomethylene) -propanedioic acid which is a yellow oil, UV 329 nm (E = 567) was obtained. 1.8 g of ethoxyanilinomethylene) -propanedioic acid ethyl ester and 2-ethylhexyl ester which is a yellow oil 329 nm UV (E = 632) was obtained.

EXAMPLE 7 Dipentyl ester of 2- (4-ethoxy-anilinomet ilen) -propandioic acid and 2- (4-ethoxy-anil inome ilen) -propanedioic acid ethyl ester pentylester The preparation was the same as in Example 6 where n-pentanol was used in place of 2-ethylhexanol. the two products of the epigraph were isolated by flash chromatography using hexane: ethyl acetate 8: 1 as eluent. 16.6 g of 2- (4-ethoxyanilinomethylene) -propanedioic acid dipentyl ester which is a yellow oil, 329 nm UV (E = 651), was obtained. 2.5 g of ethoxyanilinomethylene) -propanedioic acid ethyl ester pentyl ester which is a yellow oil 329 nm UV (E = 725) was obtained.

EXAMPLE 8 Preparation of formula type: water-in-oil emulsion Part A and part B were mixed separately at 85 ° C and then combined under stirring. Finally, the pH was corrected to 7 with 10% potassium hydroxide or 10% citric acid if necessary.

EXAMPLE 9 Preparation of formula type: water-in-oil emulsion (soft cream) Part A and part b were mixed separately at 85 ° C and then combined with stirring. Finally, the pH was corrected to 7 with 10% potassium hydroxide or 10% citric acid if necessary.

EXAMPLE 1Q Type of formula: silicon emulsion in water (lotion) Part A and part B were separately mixed at 85 ° C and then combined under stirring, finally the pH was corrected to 7 with 10% potassium hydroxide or 10% citric acid if necessary.

EXAMPLE 11 Preparation of formula type: oil in water emulsion Part A and part B were mixed separately at 85 ° C and then combined with stirring. Finally, the pH was corrected to 7 with 10% potassium hydroxide or 10% citric acid if necessary.

EXAMPLE 12 Type of formula: oil-in-water emulsion Part A and part B were mixed separately at 85 ° C and then combined with stirring. Finally, the pH was corrected to 7 with 10% potassium hydroxide or 10% citric acid if necessary.

The emulsions of examples 8, 11 and 12 showed a wide filtering activity over the entire UV region of about 280 to 400 nm with a broad maximum plateau in the range of about 300 to 360 nm.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Having described the invention as above, the content of the following is claimed as property.

Claims (11)

Claims

1. A cosmetic composition for filtering light, for protecting human skin or human hair against ultraviolet radiation characterized in that it contains in a cosmetically acceptable vehicle at least one compound of formula I wherein R represents a linear or branched alkyl chain of C 1-8, and R and R each represent, independently, a straight or branched chain alkyl

2. The light filtering composition, cosmetic, according to claim 1, characterized in that R1 represents methyl, ethyl or n-butyl, and R2 and R3 each represents, independently, methyl, ethyl, pentyl, 2-ethexyl.

3. The light filtering composition, cosmetic, according to claim 2, characterized in that R1, R2 and R3 are ethyl.

4. The light filtering composition, cosmetic, according to any of claims 1 to 3, characterized in that it comprises 0.1 to 10% by weight, preferably 0.5 to 5% by weight of the compound (s) ) of formula I.

5. The light filtering composition, cosmetic, according to claim 4, characterized in that it comprises 1 to 3% by weight of the compound (s) of formula I.

6. The light filtering composition, cosmetic, according to any of claims 1 to 5, characterized in that it comprises in addition at least one UV-B filter agent with an absorption maximum of around 300 to 320 nm and for at least one UV-A filter agent with a maximum absorption at > 340 nm, especially between 340 and 360 nm.

7. The light filtering composition, cosmetic, according to claim 6, characterized in that the UV-A filter agent is one of the group consisting of 2-methyldibenzoylmethane, 4-metyl-dibenzoyl-methane, 4-ter-but ildibenzoyl-methane, 2,4-dimethyldibenzoylmethane, 2,5-dimethyldibenzoylmethane, 4,4'-diisopropyldibenzoylmethane, 4-tert-butyl-4'-methoxydibenzoylmethane, 2-metyl-5-isopropyl-4'-methoxydibenzoylmethane, 2-methyl-5-tert-butyl-4'-methoxydibenzoylmethane, 2,4-dimethyl-4'-methoxydibenzoylmethane, 2,6-dimethyl-4-tert-butyl-4'-methoxydibenzoyl-methane and terephtalylidene dicarboxylic acid sulfonic acid.

8. The light filtering composition, cosmetic, according to claim 7, characterized in that the UV-A filter agent is 4-tert-butyl-4'-methoxydibenzoylmethane.

9. The light filtering composition, cosmetic, according to any of claims 6 to 8, characterized in that the UV-B filter agent is at least one of the group consisting of cinnamates, salicylates, benzophenones, diphenylacrylates, triazines, derivatives of camphor, polymeric UV absorbers or pigmentary metal oxides of cerium, iron, titanium, zinc or zirconium, especially of titanium or zinc, and polymers with hydrocarbon structure or siloxane structure comprising at least one ultraviolet light absorbing group.

10. The use of a cosmetic light filter composition of any of claims 1 to 9 to protect human skin or human hair against ultraviolet radiation.

11. Compounds of formula I chosen from the group consisting of 2- (4-heptoxyanilinomethylene) -propanedioic acid diethyl ester, 2- (4-methoxyanilinomethylene) -propanedioic acid dimethyl ester, 2- (4-) ethoxy-anilinomet ilen) -propandioic, 2- (4-propoxy anilinomethylene) -propanedioic acid dimethyl ester, 2- (4-butoxy-anilinomethylene) -propanedioic acid dimethyl ester, 2- (4-pentoxy-) dimethyl ester anilinomethylene) -propandioic, 2- (4-hexoxy-anilinomethylene) -propanedioic acid dimethyl ester, 2- (4-ethoxy-anilinomethylene) -propanedioic acid dipentyl ester, 2- (4-ethoxy) ethyl ester pentylester -anilinomethylene) -propanedioic acid, 2- (4-ethoxy-anilinomethylene) -propanedioic acid di-2-ethylhexyl ester and 2- (4-ethoxy-anilinomethylene) -propanedioic acid 2- ethylhexyl ester.