FR3130139A1 - Mineral photoprotective compositions with high SPI and longevity - Google Patents

Abstract

Mineral photoprotective compositions with high SPI and lifetime Mineral photoprotective compositions with high SPI and lifetime A photoprotective composition is an oil-in-water emulsion of aqueous and oily phases and comprises at least one oil thickener based on lipophilic acrylate, at least one inorganic anti-UV filter and at least one nonionic surfactant which is a fatty acid polyethylene glycol ether or fatty acid polyethylene glycol esters or a combination of the latter. The sunscreen composition may also include one or a combination of ingredients selected from the group consisting of solvents, SPI enhancers, humectants, skin care actives, oils, waxes, thickeners , preservatives, pH adjusters, chelating agents, viscosity adjusters, cooling agents, fillers, fragrances, colorants, pigments and combinations thereof. The photoprotective composition has an SPI in a range of about 30 to about 55 and exhibits phase stability and processability. Figure for abstract: None

Description

Mineral photoprotective compositions with high SPI and longevity

The present invention relates to photoprotective compositions and methods of using the photoprotective compositions to protect keratin substrates such as skin and hair from UV radiation.

Context

The negative effects of exposure to ultraviolet (“UV”) light are well known. Prolonged exposure to sunlight causes damage such as sunburn to the skin and dries out the hair, making it brittle. When the skin is exposed to UV light having a wavelength of about 290 nm to about 400 nm, long-term damage can lead to serious conditions such as skin cancer.

UV light also contributes to aging by causing the formation of free radicals in the skin. Free radicals include, for example, singlet oxygen, hydroxyl radical, superoxide anion, nitric oxide and hydrogen radicals. Free radicals attack DNA, membrane lipids and proteins, generating carbon radicals. These in turn react with oxygen to produce a peroxyl radical which can attack adjacent fatty acids to generate new carbon radicals. This cascade leads to a chain reaction producing lipid peroxidation products. Cell membrane damage results in loss of cellular permeability, increased intercellular ionic concentration, and decreased ability to excrete or detoxify wastes. The end result is a loss of skin elasticity and the appearance of wrinkles. This process is commonly referred to as photo-aging.

Sunscreens can be used to protect against UV damage and delay the signs of photoaging. The degree of protection against UV provided by a photoprotective composition is directly linked to the quantity and to the type of anti-UV filters which it contains. The greater the quantity of UV filters, the greater the degree of protection against UV rays (UVA/UVB). Consumers prefer sunscreen compositions to contain natural, non-irritating components that look natural (unnoticeable) when applied. It is recognized that there are challenges in providing mineral-based sunscreen products with a high sun protection factor (SPI) that have a long shelf life and are able to maintain the benefit of the SPI.

The inventors of the present invention have formulated a mineral-based sunscreen which unexpectedly exhibits high SPF and high emulsion structural stability in the presence of significant amounts of mineral-based sunscreens which also provide good aesthetic appeal.

Summary

The present invention relates to a photoprotective composition which comprises mineral UV-filtering agents, which are known to be non-irritating, natural and gentle on the skin, as well as oil-based acrylic thickeners and non-ionic surfactants which provide protection stable sunscreen and emulsion structural stability in the presence of high amounts of mineral UV filters. The photoprotective composition addresses challenges known in the art where high levels of mineral UV filters have been found to be unstable, as described in more detail herein. The photoprotective composition may optionally comprise organic UV filters.

In various embodiments, the sunscreen composition includes nonionic surfactants that are selected from polyethylene glycol ethers of fatty acids or polyethylene glycol esters of fatty acids to provide a composition that can, unexpectedly, be prepared on a commercial scale and which demonstrates structural stability of the IPS and the emulsion which exceeds what has been observed with similar compositions which include mineral sunscreens and oil thickeners based on lipophilic acrylate without selected surfactants. The photoprotective composition has an in vivo tested SPI value of 50 or more.

The composition according to the invention relates to a photoprotective composition comprising an oil-in-water emulsion of aqueous and oily phases, comprising:

i. at least one lipophilic acrylate-based oil thickener,

ii. at least one mineral UV filter;

iii. at least one nonionic surfactant selected from the group consisting of polyethylene glycol ethers, polyethylene glycol esters of fatty acids, and combinations thereof

wherein the composition has an SPI in a range of 30 to 55 and exhibits phase stability and processability.

In particular, the at least one lipophilic acrylate based oil thickener comprises a C10-C30 alkyl acrylate polymer.

In particular, the at least one nonionic surfactant comprises steareth-2, steareth-20 or a combination thereof.

In particular, the at least one inorganic UV filter comprises zinc oxide, a derivative of zinc oxide, titanium dioxide, a derivative of titanium dioxide or combinations of these.

In particular, the composition according to the invention also comprises one or more non-mineral anti-UV filters chosen from organic anti-UV filters.

In particular, the composition according to the invention further comprises one or more organic UV filters comprising homosalate, octisalate and octocrylene, more particularly, in which the UV filter comprises zinc oxide, present in an amount ranging from 5% to 10%, and in which the homosalate is present in an amount ranging from 5% to 15%, the octisalate is present in an amount ranging from 1% at 7% and the octocrylene is present in an amount ranging from 7% to 15%, each by weight, based on the total weight of the sunscreen composition.

In particular, the photoprotective composition according to the invention further comprises one or a combination of additives chosen from the group consisting of solvents, SPI enhancers, humectants, skin care active ingredients, oils , waxes, thickeners, preservatives, pH adjusters, chelating agents, viscosity adjusters, cooling agents, fillers, fragrances, colorants, pigments and combinations thereof .

In particular, the sunscreen composition exhibits emulsion structural stability wherein the sunscreen composition does not show signs of phase separation and does not lose homogeneity after up to 12 weeks at room temperature in the range of 25°C. up to and including 45°C and maintains a processability in which the sunscreen composition can be produced on a commercial scale characterized by a production volume of at least 15 kilograms without loss of structural stability of the emulsion, and wherein the photoprotective composition exhibits an SPI (in vivo) in a range of 30 to 55.

The invention also relates to a photoprotective composition comprising an oil-in-water emulsion of aqueous and oily phases, comprising:

i. at least one or more lipophilic acrylate-based oil thickeners, present at 1.8%;

ii. at least one mineral UV filter, present at 7%

iii. at least one or more nonionic surfactants selected from the group consisting of polyethylene glycol ethers, polyethylene glycol esters of fatty acids and combinations thereof, present in a total amount of 2%;

iv. at least one or more organic UV filters, present at a total of 18% and

v. one or a combination of ingredients selected from the group consisting of solvents, SPI enhancers, humectants, skin care actives, oils, waxes, thickeners, preservatives, pH adjusters, chelating agents, viscosity adjusters, cooling agents, fillers, fragrances, colorants, pigments and combinations thereof.

The invention describes a photoprotective composition which comprises: a water-in-oil emulsion of the aqueous and oily phases, comprising the following elements:

1. at least one lipophilic acrylate-based oil thickener,
2. at least one mineral UV filter;
3. at least one nonionic surfactant selected from the group consisting of polyethylene glycol ethers of fatty acids, polyethylene glycol esters of fatty acids, and combinations thereof

wherein the formulation has an SPI in a range of about 30 to about 55 and exhibits phase stability and processability.

In certain embodiments, the photoprotective composition comprises one or more non-mineral UV filters, selected organic UV filters.

In certain embodiments described, the photoprotective composition comprises: a water-in-oil emulsion of the aqueous and oily phases, comprising the following elements:

1. at least one lipophilic acrylate based oil thickener, present from about 0.5% to about 5%;
2. at least one mineral UV filter, present from approximately 1% to approximately 25% and
3. at least one nonionic surfactant selected from the group consisting of polyethylene glycol ethers, polyethylene glycol esters of fatty acids, and combinations thereof, present from at least approximately 0.1% to approximately 5%,

wherein the components are present by weight, based on the total weight of the photoprotective composition.

In certain embodiments described, the photoprotective composition comprises: a water-in-oil emulsion of the aqueous and oily phases, comprising the following elements:

1. at least one lipophilic acrylate based oil thickener, present from about 0.75% to about 3%;
2. at least one mineral UV filter, present from about 5% to about 15% and
3. at least one nonionic surfactant selected from the group consisting of polyethylene glycol ethers, polyethylene glycol esters of fatty acids, and combinations thereof, present from at least about 0.2% to about 3%,

wherein the components are present by weight, based on the total weight of the photoprotective composition.

In certain embodiments described, the photoprotective composition comprises: a water-in-oil emulsion of the aqueous and oily phases, comprising the following elements:

1. at least one or more lipophilic acrylate-based oil thickeners, present at about 1.8%;
2. at least one mineral UV filter, present at about 7%;
3. at least one or more nonionic surfactants selected from the group consisting of polyethylene glycol ethers, polyethylene glycol esters of fatty acids and combinations thereof, present in a total amount of approximately 2%;
4. at least one or more organic UV filters, present in a proportion of approximately 18% in total and
5. one or a combination of solvents,

wherein the components are present by weight, based on the total weight of the photoprotective composition.

In certain embodiments described, the photoprotective composition comprises: a water-in-oil emulsion of the aqueous and oily phases, comprising the following elements:

1. at least one or more lipophilic acrylate-based oil thickeners comprising a C12-22 alkyl acrylate/hydroxyethyl acrylate copolymer;

1. at least one mineral UV filter selected from the group consisting of zinc oxide, a derivative of zinc oxide, titanium dioxide, a derivative of titanium dioxide and combinations thereof;
2. at least one or more nonionic surfactants selected from the group consisting of steareth-2, steareth-20 and combinations thereof;
3. at least one or more organic UV filters chosen from the group consisting of homosalate, octisalate and octocrylene and their combinations and
4. one or a combination of additives selected from the group consisting of glycerin, propanediol, ethylhexyl methoxycrylene, butyloctyl salicylate, dicaprylyl carbonate, dicaprylyl ether, isopropyl palmitate, diethylhexyl syringylidenemalonate, trisodium ethylenediamine disuccinate, hydroxyacetophenone, citric acid, coco caprylate/caprate, oryza sativa wax, candelilla wax, sunflower seed wax, carnauba wax, polyhydroxystearic acid, xanthan gum, chlorphenesin and combinations thereof.

In some embodiments, the at least one lipophilic acrylate-based oil thickener includes a spacer polymer. In some embodiments, the at least one lipophilic acrylate oil thickener comprises a C12-22 alkyl acrylate/hydroxyethyl acrylate copolymer.

In some embodiments, the at least one nonionic surfactant selected from the group consisting of polyethylene glycol ethers, polyethylene glycol esters of fatty acids includes steareth-2, steareth-20, or a combination thereof. In some embodiments, the at least one nonionic surfactant selected from the group consisting of polyethylene glycol ethers, polyethylene glycol esters of fatty acids includes steareth-2 and steareth-20.

In some embodiments, the at least one inorganic UV filter comprises zinc oxide, a derivative of zinc oxide, titanium dioxide, a derivative of titanium dioxide, or combinations thereof.

In the various embodiments, the sunscreen composition comprises one or a combination of organic UV filters and one or a combination of inorganic/mineral UV filters. In some particular embodiments, the inorganic/mineral UV filters include zinc oxide and the optional organic UV filters each include homosalate, octisalate, and octocrylene.

In certain embodiments of the photoprotective composition that includes organic UV filters, the combination of organic and inorganic/mineral UV filters are present in the photoprotective composition in a total amount ranging from about 15% to about 45% or from about 20% to about 25% based on the total weight of the photoprotective composition.

In certain embodiments of the photoprotective composition, the combination of organic and inorganic/mineral UV filters comprises zinc oxide present in an amount between about 5% and about 10%, and a mixture of UV filters. organic UVs comprising homosalate present in an amount in the range of about 5% to about 15%, octisalate present in an amount in the range of about 1% to about 7%, and octocrylene present in an amount in the range of about 7% to about 15%, each present by weight based on the total weight of the sunscreen composition.

In some embodiments, the water phase components and the oil phase components, respectively, are present in the sunscreen composition at a weight ratio of water components to oil components within a range of about >1:1. In some embodiments, a phase ratio of the aqueous phase to the non-aqueous phase is calculated based on the total weight of the aqueous phase components relative to the weight of the non-aqueous oil phase components.

In certain embodiments, the photoprotective composition also comprises one or more SPI enhancers, one or more sensory fatty compounds or powders modifying the feeling or one or more active products.

In some embodiments, the sunscreen composition further comprises one or a combination of additives selected from the group consisting of solvents, SPI enhancers, humectants, waxes, skin care actives, oils, thickeners, preservatives, pH adjusters, chelating agents, viscosity adjusters, cooling agents, fillers, fragrances, colorants, pigments and combinations thereof.

In one or more particular embodiments, the photoprotective compositions further comprise one or a combination of additives chosen from the group consisting of glycerin, propanediol, ethylhexyl methoxycrylene, butyloctyl salicylate, dicaprylylic carbonate, dicaprylyl ether, isopropyl palmitate, diethylhexyl syringylidenemalonate, trisodium ethylenediamine disuccinate, hydroxyacetophenone, citric acid, caprylate/caprate coco, oryza sativa wax, candelilla wax, wax of sunflower seeds, carnauba wax, polyhydroxystearic acid, xanthan gum, chlorphenesin and combinations thereof.

In the various embodiments, the sunscreen composition exhibits emulsion structural stability wherein the sunscreen composition does not show signs of phase separation, and/or does not lose homogeneity after up to 12 weeks at room temperature. in the range of about 25°C up to and including about 45°C, and maintains a processability in which the sunscreen composition can be produced on a commercial scale characterized by a production volume of at least 15 kilograms without loss structural stability of the emulsion. In the various embodiments, the sunscreen composition exhibits an SPI (in vivo) within a range of about 30 to about 55. In some embodiments, the sunscreen composition has an SPI of about 30, or about 45 or about 50.

In various embodiments, the sunscreen composition may exclude one or more ingredients selected from the group consisting of geminal surfactants, anionic gelling agents, Aristoflex polymers, pigments, iron oxides, and combinations thereof.

The present invention also relates to methods for protecting the skin against UV radiation comprising the application to the skin of an effective amount of the photoprotective composition disclosed in the present file.

Claims (10)

A photoprotective composition comprising an oil-in-water emulsion of aqueous and oily phases, comprising:
i. at least one lipophilic acrylate-based oil thickener,
ii. at least one mineral UV filter;
iii. at least one nonionic surfactant selected from the group consisting of polyethylene glycol ethers, polyethylene glycol esters of fatty acids, and combinations thereof
wherein the composition has an SPI in a range of 30 to 55 and exhibits phase stability and processability. The sunscreen composition of claim 1, wherein the at least one lipophilic acrylate-based oil thickener comprises a C10-C30 alkyl acrylate polymer. The sunscreen composition according to claim 1, wherein the at least one nonionic surfactant comprises steareth-2, steareth-20 or a combination thereof. The photoprotective composition according to any one of claims 1-3 wherein the at least one mineral UV filter comprises zinc oxide, a derivative of zinc oxide, titanium dioxide, a derivative of titanium or combinations thereof. The photoprotective composition according to 1, further comprising one or more non-mineral anti-UV filters chosen from organic anti-UV filters. The photoprotective composition according to any preceding claim, further comprising one or more organic UV filters comprising homosalate, octisalate and octocrylene. The photoprotective composition according to claim 6, in which the anti-UV filter comprises zinc oxide, present in an amount ranging from 5% to 10%, and in which the homosalate is present in an amount ranging from 5% at 15%, the octisalate is present in an amount ranging from 1% to 7% and the octocrylene is present in an amount ranging from 7% to 15%, each by weight, based on the total weight of the photoprotective composition. The sunscreen composition of any preceding claim further comprises one or a combination of additives selected from the group consisting of solvents, SPI enhancers, humectants, skin care actives, oils, waxes, thickeners, preservatives, pH adjusters, chelating agents, viscosity adjusters, cooling agents, fillers, fragrances, colorants, pigments and combinations thereof last. The sunscreen composition according to any preceding claim, wherein the sunscreen composition exhibits emulsion structural stability wherein the sunscreen composition does not show signs of phase separation and does not lose homogeneity after up to 12 weeks at an ambient temperature in the range of 25°C up to and including 45°C and maintains a processability in which the sunscreen composition can be produced on a commercial scale characterized by a production volume of at least 15 kilograms without loss of structural stability of the emulsion, and wherein the photoprotective composition exhibits an SPI (in vivo) in a range of 30 to 55. A photoprotective composition comprising an oil-in-water emulsion of aqueous and oily phases, comprising:
i. at least one or more lipophilic acrylate-based oil thickeners, present at 1.8%;
ii. at least one mineral UV filter, present at 7%
iii. at least one or more nonionic surfactants selected from the group consisting of polyethylene glycol ethers, polyethylene glycol esters of fatty acids and combinations thereof, present in a total amount of 2%;
iv. at least one or more organic UV filters, present at a total of 18% and
v. one or a combination of ingredients selected from the group consisting of solvents, SPI enhancers, humectants, skin care actives, oils, waxes, thickeners, preservatives, pH adjusters, chelating agents, viscosity adjusters, cooling agents, fillers, fragrances, colorants, pigments and combinations thereof.