Sunscreen compositions and methods for protection from ultraviolet and visible light

Abstract

Provided herein is a method for reducing or preventing sunburn caused by visible light and ultraviolet radiation in a subject. The method comprises topically applying to the subject a sunscreen composition comprising an inorganic UV filter, an antioxidant and at least one inorganic pigment, wherein the at least one inorganic pigment and the antioxidant are present in an amount effective to reduce or prevent sunburn caused by visible light. Also provided herein is a method for increasing the SPF of a sunscreen composition and a sunscreen composition comprising at least one inorganic UV filter.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Patent Application No. 63 / 260980, filed September 8, 2021, the disclosure of which is incorporated herein by reference in its entirety.

[0002] Disclosed herein are compositions for topical sun protection that include a combination of an ultraviolet (UV) filter, at least one inorganic pigment, and an antioxidant that includes vitamin E, vitamin C, or derivatives of vitamin E and vitamin C, such as tocopherol acetate and tetrahexadecyl ascorbate, respectively. The compositions disclosed herein may be used to protect against both visible light-induced erythema and ultraviolet radiation-induced erythema. [Background technology]

[0003] The electromagnetic spectrum is the spectrum with the range of frequencies of electromagnetic radiation and their corresponding wavelengths, ranging from radio waves at the lowest wavelength to gamma ionizing radiation waves at the highest wavelength. The spectrum is broadly divided into the following bands, starting from the lowest frequency: radio waves, microwaves, infrared, visible light, ultraviolet light, x-rays, and gamma rays. Initially, only visible light, with its corresponding wavelengths ranging from about 400 nm to about 700 nm, was known to exist. Meanwhile, in 1801, Johann Ritter discovered that the UV portion of the electromagnetic spectrum, with its corresponding wavelengths ranging from about 10 nm to about 400 nm, is photochemically and photobiologically active. The most common source of UV light is the sun, and it is the radiation resulting from UV light that causes what is commonly referred to as "sun dermatitis" or "erythema." The UV band of the electromagnetic spectrum itself includes three sub-spectra: UVA (about 320-400 nm), UVB (about 280-320 nm), and UVC (about 100-280 nm).

[0004] Photodermatitis is a reddening of the skin resulting from prolonged exposure to the sun. The severity of photodermatitis can range from mild to severe, based on several factors including the length of exposure, the intensity of exposure, and the individual's skin type, with fair skin being at greater risk. Photodermatitis is a well-known risk factor for skin cancer.

[0005] Until recently, there was no significant contribution to sunburn from visible light wavelengths (i.e., 400 nm and above), and sunburn was thought to be caused exclusively by light in the UV wavelength range (i.e., 10-400 nm). UV-induced erythema, commonly known as sunburn, was thought to be induced by direct absorption damage to certain chromophores (mainly DNA) and other proteins in the epidermis and dermis by exposure to UVB radiation, and also indirect damage by photooxidation processes caused by UVB and UVA radiation. For UVA-induced photooxidative damage, absorbed radiation energy raises oxygen to triplet or singlet excited energy levels, which allows the radiation energy to interact with and damage other cellular structures in the surroundings, ultimately resulting in erythema of the skin if the absorbed radiation energy is present in sufficient quantities.

[0006] Action spectra have been derived to express the exact dose of irradiance required to produce erythema at each specific wavelength and are reported to encompass the wavelength range of about 250-400 nm. All published action spectra for erythema stop at exactly 400 nm, as if to say that wavelengths above 400 nm have no consequence and therefore no contribution to the erythema reaction. See, for example, Non-Patent Document 1.

[0007] More recently, it has been discovered that this assumption is incorrect and that the visible portion of the electromagnetic spectrum and especially the violet and / or blue light region around 400-500 nm can and does have an effect on the induction of erythema, especially when considering outdoor sun exposure where the sun produces a large amount (e.g., 50%) of visible light compared to the relatively small amount (e.g., 5%) of ultraviolet light on land. For example, Zastrow and colleagues have demonstrated that free radicals (excited oxygen molecules) can be generated in skin tissue by wavelengths spanning the ultraviolet light spectrum and the entire visible light spectrum. Combining the action spectrum with the terrestrial solar spectrum, it has been estimated that 50% of the free radicals generated by sunlight are contributed by the visible portion of the solar spectrum and the remaining 50% by the ultraviolet portion. See Non-Patent Document 2.

[0008] Nevertheless, the active ingredients in traditional sunscreen products are usually only intended to filter UV rays (mainly UVA and UVB), not the effects of visible light. Typical UV absorbers in sunscreen products can be organic (e.g., avobenzone, oxybenzone, octyl methoxycinnamate, etc.) or inorganic (e.g., titanium dioxide, zinc oxide, etc.). Many consumers do not want sunscreen to be visible on their skin, so manufacturers of these products have been working hard to produce invisible sunscreen products. Zinc oxide and titanium dioxide have been widely used in sunscreen products since about 1987, but they are usually included in sunscreen products using small particle sizes, such as nano-sized particles. The nano-sized particles minimize the visible appearance of zinc oxide and titanium dioxide, making the sunscreen product virtually invisible on the skin after application, while still functioning to absorb the harmful effects of UV radiation from the sun. See Non-Patent Document 3.

[0009] Nanoparticle-sized zinc oxide and titanium dioxide act as semiconducting absorbers of UV radiation below about 370-380 nm, depending on their band gap energy, and thus still function as UV filters. Nanoparticle-sized zinc oxide and titanium dioxide, due to their micron / nanoparticle size, do not generally scatter and reflect radiation above those wavelengths. Thus, these inorganic-based sunscreens also offer little or no protection against radiation in the visible portion of the electromagnetic spectrum, and only marginal protection against wavelengths at the upper end of the UVA spectrum (e.g., 375-400 nm).

[0010] Thus, there is a need for a sunscreen composition that provides protection against both UV radiation in sunlight and the visible light portion of the solar spectrum. Ideally, the sunscreen composition should be consumer acceptable in appearance and provide greater protection to the skin against erythema than conventional UV-only protection sunscreen products. [Prior art documents] [Non-patent literature]

[0011] [Non-Patent Document 1] Schmalwieser, A. et al., A library of action spectra for erythema and pigmentation, Photochem.Photobiol.Sci.2012;11(2):252-268 [Non-Patent Document 2] Zastrow, L. et al., The missing link,light(280~1600nm)induced free radical formation in human skin,Skin Pharmacol.Physiol.2009;22:31-34 [Non-Patent Document 3] Cole C. et al., Metal oxide sunscreens protect skin by absorption,not by reflection or scattering,Photomed.Photoimmunol.Photodermatol.2016 32:1,5-10 Summary of the Invention

[0012] Disclosed herein are sunscreen compositions and methods of using the sunscreen compositions that reduce or prevent sunburn caused by both visible light and ultraviolet (UV) radiation, as well as methods of increasing the Sun Protection Factor (SPF) of sunscreen compositions.

[0013] In an embodiment, a sunscreen composition is disclosed herein, the sunscreen composition comprising: (a) inorganic UV filters comprising or consisting of zinc oxide and titanium dioxide, present in the sunscreen composition in a total amount ranging from about 10% to about 50% by weight, based on the total weight of the sunscreen composition; (b) antioxidants comprising or consisting of vitamin E or a derivative thereof and vitamin C or a derivative thereof, present in the sunscreen composition in a total amount ranging from about 0.1% to about 5% by weight, based on the total weight of the sunscreen composition; and (c) at least one inorganic pigment comprising or consisting of iron oxide, present in the sunscreen composition in a total amount ranging from about 0.1% to about 10% by weight, based on the total weight of the sunscreen composition, wherein the at least one inorganic pigment and antioxidant are present in an amount effective to reduce or prevent visible light induced sunburn.

[0014] Also disclosed herein is a method for reducing or preventing sunburn in a subject caused by visible light and UV radiation, the method comprising the step of topically applying to the subject a sunscreen composition comprising: (a) an inorganic UV filter comprising zinc oxide and titanium dioxide; (b) an antioxidant comprising vitamin E or a derivative thereof and vitamin C or a derivative thereof; and (c) at least one inorganic pigment comprising iron oxide, wherein the at least one inorganic pigment and the antioxidant are present in an amount effective to reduce or prevent sunburn caused by visible light.

[0015] Also disclosed herein is a method for increasing the SPF of a sunscreen composition comprising at least one inorganic UV filter, the method comprising the steps of adding to the sunscreen composition (a) an antioxidant comprising vitamin E or a derivative thereof and vitamin C or a derivative thereof, and (b) at least one inorganic pigment comprising an iron oxide, wherein the at least one inorganic pigment and the antioxidant are present in an amount effective to increase the SPF of the sunscreen composition, e.g., an amount effective to increase the SPF of the sunscreen composition by at least about an SPF of 3 when the sunscreen composition is tested under outdoor sunlight exposure conditions.

[0016] In some embodiments, the inorganic UV filters are present in the sunscreen composition in a total amount ranging from about 10% to about 50% by weight, based on the total weight of the sunscreen composition. In some embodiments, the antioxidants are present in the sunscreen composition in a total amount ranging from about 0.1% to about 5% by weight, based on the total weight of the sunscreen composition, and in some embodiments, the at least one inorganic pigment is present in the sunscreen composition in a total amount ranging from about 0.1% to about 10% by weight, based on the total weight of the sunscreen composition.

[0017] In various embodiments of the present disclosure, the iron oxide is selected from the group consisting of black iron oxide, brown iron oxide, red iron oxide, yellow iron oxide, and mixtures thereof.

[0018] In some embodiments, the zinc oxide has an average particle size ranging from about 10 nm to about 100 nm, and in some embodiments, the titanium dioxide has an average particle size ranging from about 5 nm to about 20 nm. In various aspects of the present disclosure, at least one of the zinc oxide, titanium dioxide, and at least one inorganic pigment (e.g., iron oxide) further comprises a coating such as, for example, triethoxycaprylylsilane.

[0019] In certain aspects of the disclosure, vitamin E or a derivative thereof is selected from the group consisting of tocopherol and tocopherol acetate, and in certain aspects, vitamin C or a derivative thereof is selected from the group consisting of ascorbic acid and tetrahexyldecyl ascorbate.

[0020] In some embodiments, the sunscreen compositions disclosed herein further comprise at least one additional ingredient selected from the group consisting of emollients, organic UV filters, skin conditioning agents, preservatives, and silica, and in some embodiments, the sunscreen compositions disclosed herein are free of organic UV filters.

[0021] In some embodiments, the at least one inorganic pigment further comprises at least one inorganic pigment selected from the group consisting of pigmentary zinc oxide and pigmentary titanium dioxide. For example, in some embodiments, the pigmentary zinc oxide may have an average particle size ranging from greater than about 100 nm to about 1000 nm, and in some embodiments, the pigmentary titanium dioxide may have an average particle size ranging from about 1 μm to about 20 μm.

[0022] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present teachings as claimed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Reference will now be made in detail to embodiments of the present teachings. In the following description, references will be made to exemplary embodiments in which the present teachings may be practiced. Accordingly, the following description is by way of example only.

[0024] Disclosed herein is a sunscreen composition that provides protection to the skin against both the visible and UV portions of the sun's radiation, and a method of using the sunscreen composition to reduce or prevent sunburn resulting from both the visible and UV portions of the sun's radiation, and a method of increasing the SPF of the sunscreen composition. The sunscreen composition disclosed herein includes a pigment that absorbs the sun's visible light, primarily in the blue region, and an antioxidant that quenches free radicals induced by the sun's visible radiation, thereby reducing or preventing erythema.

[0025] In one embodiment, disclosed herein is a sunscreen composition comprising a combination of at least one inorganic pigment, such as iron oxide, together with titanium dioxide and zinc oxide UV filters, and an antioxidant, such as vitamin E (tocopherol or a derivative thereof, e.g., tocopherol acetate) and vitamin C (ascorbic acid or a derivative thereof, e.g., tetrahexyldecyl ascorbate). The sunscreen composition disclosed herein provides superior protection against sun-induced erythema, as compared to conventional sunscreen products, such as conventional sunscreens having an SPF of at least 60 (e.g., as determined using a protocol defined by the International Organization for Standardization (ISO) 24444:2019). The at least one inorganic pigment, such as iron oxide, provides visible light protection together with the antioxidants vitamin E and vitamin C in a manner that is cosmetically acceptable and can be tailored by concentration and color level to match the skin color of the user.

[0026] The sunscreen composition disclosed herein can be formulated to provide comfortable physical and tactile characteristics to the user. In some embodiments, the sunscreen composition disclosed herein can further comprise at least one silicone-based emollient, for example, to provide the product with a smooth and dry feel after application. In some embodiments, the sunscreen composition can further comprise silica.

[0027] definition As used throughout, ranges are used collectively to describe each and every value within a range. Any value within a range may be selected as a terminus of the range. Furthermore, all documents cited herein are incorporated by reference in their entirety. In the event of a conflict between the definitions in this disclosure and those in the cited documents, this disclosure shall control. The following terms and their equivalents shall have the following meanings unless the context clearly dictates otherwise.

[0028] The term "at least one of" is used to mean that one or more of the listed items may be selected. For example, if the list of items is A and B, then at least one of A and B refers to A only, B only, or A and B.

[0029] The term "about" is understood to encompass the range of normal variation accepted in the art, and may include, for example, within 10%, 1%, 0.1%, or 0.01% of a stated value. Unless otherwise specified, all numerical values ​​provided herein are understood to be modified by the term "about."

[0030] As used herein, the term "erythema" is used interchangeably with the term "sunburn" to refer to the superficial reddening of the skin caused by excessive exposure to radiation from the electromagnetic spectrum, including both visible light and UV radiation. As used herein, erythema and sunburn are distinguished from increased pigmentation of the skin (e.g., tanning).

[0031] As used herein, the terms "ultraviolet radiation" or "UV radiation" refer to electromagnetic radiation in the range of about 290 nm to about 400 nm. Within the spectrum of UV radiation, UVB radiation is electromagnetic radiation in the range of about 290 nm to about 320 nm, while UVA is electromagnetic radiation in the range of about 320 nm to about 400 nm.

[0032] As used herein, the term "visible light" refers to electromagnetic radiation in the range of about 400 nm to about 700 nm. Within the visible light spectrum, the violet light region spans from about 380 to 450 nm, the blue light region spans from about 450 to 495 nm, the green light region spans from about 495 to 570 nm, the yellow light region spans from about 570 to 590 nm, the orange light region spans from about 590 to 625 nm, and the red light region spans from about 625 to 700 nm.

[0033] As used herein, the terms "sun protection factor" and "SPF" refer to a measurement of how much solar energy is required to produce erythema or sunburn on skin after application of a sunscreen composition, relative to the amount of solar energy required to produce erythema on skin without the sunscreen composition applied thereto. The amount of solar energy can be affected by both the length of exposure (time) and the intensity of the solar energy. Solar intensity can be related to time of day, geographic location (higher latitudes can increase solar intensity), and weather (e.g., cloud cover).

[0034] As used herein, the term "effective amount" refers to an amount of a sunscreen composition that is sufficient when applied or administered in an appropriate amount and frequency to prevent, reduce or alleviate the damage caused by sunburn.

[0035] Additional definitions are set forth throughout the detailed description.

[0036] Sunscreen composition Disclosed herein are sunscreen compositions that, when applied topically to a user's skin, are useful for reducing or preventing damage, such as sunburn, caused by visible and UV radiation.

[0037] In one embodiment, a sunscreen composition is disclosed, the sunscreen composition comprising: (1) an inorganic UV filter comprising or consisting of zinc oxide and titanium dioxide; (2) an antioxidant comprising or consisting of vitamin E or a derivative thereof and vitamin C or a derivative thereof; and (3) at least one inorganic pigment comprising or consisting of iron oxide, wherein the at least one inorganic pigment and the antioxidant are present in an amount effective to reduce or prevent sunburn caused by visible light.

[0038] UV filters In some embodiments, the sunscreen composition comprises at least one inorganic UV filter selected from the group consisting of titanium dioxide, zinc oxide, cerium oxide, zirconium oxide, and mixtures thereof. The inorganic UV filter may act to filter or absorb UV radiation from the UV band of the electromagnetic spectrum, including, for example, UVA and UVB radiation, approximately between 320-400 nm and 280-320 nm, respectively.

[0039] In various embodiments of the present disclosure, the sunscreen composition comprises zinc oxide as an inorganic UV filter. The zinc oxide may be present as micron- or nano-sized solid particles having an average particle size ranging from about 10 nm to about 400 μm, such as from about 10 nm to about 25 μm, from about 10 nm to about 10 μm, or from about 15 nm to about 5 μm. As used herein, "nano-sized" or "nanoparticles" refers to a particle size of about 1000 nm or less, such as from about 1 nm to about 1000 nm, or from about 1 nm to about 100 nm, while "micron" or "micron-sized" refers to a particle size ranging from about 1 μm (i.e., about 1000 nm) to about 1000 μm. In embodiments in which zinc oxide is present as a UV filter, the zinc oxide may comprise nanoparticles having an average particle size ranging from about 5 nm to about 1000 nm, such as from about 10 nm to about 1000 nm, from about 30 nm to about 200 nm, from about 40 nm to about 100 nm, from about 60 nm to about 80 nm, from about 10 nm to about 50 nm, or from about 25 nm to about 40 nm or about 80 nm, as described below, however, the zinc oxide may be present in the sunscreen compositions disclosed herein as at least one inorganic pigment of a pigment size, indicating that the zinc oxide may be larger than the nanoparticle size having an average particle size ranging from about 1 μm to about 400 μm, such as from about 200 nm to about 500 nm, from about 100 nm to about 1000 nm, or from about 10 μm to about 100 μm, from about 2 μm to about 25 μm, from about 5 μm to about 20 μm, or from about 10 μm to about 15 μm. In some embodiments, the zinc oxide comprises a mixture of nanoparticles (eg, for UV filtering protection) and larger micron-sized particles (eg, for visible light scattering protection).

[0040] Zinc oxide, alone or with other components of the sunscreen, may be present in the sunscreen composition in any amount effective to filter UV rays so as to prevent or reduce the effects of sunburn when topically applied to a user. In embodiments, zinc oxide may be present in the sunscreen composition in an amount ranging from about 1% to about 25% by weight, such as about 5% to about 20% or about 10% to about 15%, e.g., about 10%, about 11%, about 12%, about 13%, or about 15%, based on the total weight of the sunscreen composition.

[0041] In some embodiments, the sunscreen compositions disclosed herein may include titanium dioxide as an inorganic UV filter in addition to or in place of zinc oxide. As described above for zinc oxide, titanium dioxide may be present as micron- or nano-sized solid particles having an average particle size ranging from about 10 nm to about 100 μm, such as about 10 nm to about 25 μm, about 10 nm to about 10 μm, or about 15 nm to about 5 μm. In some embodiments in which titanium dioxide is present as a UV filter, the titanium dioxide may include nanoparticles having an average particle size ranging from about 5 nm to about 1000 nm, such as about 5 nm to about 500 nm, about 10 nm to about 50 nm, or about 15 nm to about 40 nm, or about 15 nm. Titanium dioxide nanoparticles may also form aggregates having a larger average particle size, such as an average aggregate particle size ranging from about 100 nm to about 1000 nm, such as about 200 nm to about 500 nm, or about 250 nm to about 400 nm. In some embodiments, the titanium dioxide may be larger than nanoparticle sized with an average particle size ranging from about 1 μm to about 25 μm, such as from about 5 μm to about 20 μm or from about 10 μm to about 15 μm. In some embodiments, the titanium dioxide comprises a mixture of nanoparticles (e.g., for UV filtering protection) and larger micron sized particles (e.g., for visible light scattering protection).

[0042] Titanium dioxide, alone or with other components of the sunscreen, may be present in the sunscreen composition in any amount effective to filter UV rays so as to prevent or reduce the effects of sunburn when topically applied to a user. In embodiments, titanium dioxide may be present in the sunscreen composition in an amount ranging from about 1% to about 25%, such as about 5% to about 20% or about 5% to about 15%, by weight based on the total weight of the sunscreen composition, for example, about 5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 11%, about 12%, about 13%, about 14%, or about 15%.

[0043] Overall, inorganic UV filters, including both zinc oxide and titanium dioxide, may be present in the sunscreen composition in an amount ranging from about 2% to about 50%, such as about 5% to about 50%, about 10% to about 45%, or about 15% to about 20%, by weight, based on the total weight of the sunscreen composition, for example, about 15%, about 16%, about 17%, about 18%, about 19%, about 20%, about 21%, about 22%, about 23%, about 24%, or about 25%.

[0044] In some embodiments, the at least one inorganic UV filter agent can be a surface-treated inorganic UV filter agent. Surface-treating the at least one inorganic UV filter agent can reduce or prevent the optical reactivity of the agent and / or aid in mixing with other ingredients in the sunscreen composition. Surface-treated inorganic UV filter agent indicates that the UV filter agent is surface-treated by any means, including chemical, electrical and / or mechanical means. In some embodiments, surface-treating the at least one inorganic UV filter agent can enhance the water-resistant properties of the UV filter agent and the sunscreen composition. In some embodiments, all of the UV filters present in the sunscreen composition are surface-treated.

[0045] Inorganic UV filters can be surface-treated by any surface treatment method or agent known in the art.In some embodiments, at least one inorganic UV filter can comprise coated particles.Coatings can comprise hydrophobic materials such as alkylsiloxanes (e.g., triethoxycaprylylsilane), organic titanates, halogenated phosphates (e.g., perfluoroalkylphosphonates), halogenated organic silanes, modified amino acids (e.g., disodium stearoyl glutamate), silicones, or metal salts of fatty acids.

[0046] Exemplary embodiments of the surface-treated coated UV filter agent may include, for example, coated zinc oxide, such as triethoxycaprylylsilane zinc oxide (e.g., Z-Cote® HP1) and / or coated titanium dioxide, such as triethoxycaprylylsilane titanium dioxide (e.g., CM3K40T4 from Kobo products, Inc., and UV Cut TiO2-41).

[0047] Inorganic Pigments In various embodiments, the sunscreen composition disclosed herein may further comprise at least one inorganic pigment. Without being bound by theory, it is believed that the inorganic pigment acts to absorb the sun's visible light, such as visible light in the blue region of the visible light spectrum (e.g., about 450 nm to about 495 nm) and the violet region of the visible light spectrum (e.g., about 380 nm to about 450 nm), which may overlap with UVA radiation in the upper range of the UVA spectrum (e.g., about 375 nm to about 400 nm). Exemplary inorganic pigments may include titanium dioxide; zinc oxide; iron oxides, including black iron oxide, brown iron oxide, red iron oxide, and yellow iron oxide; manganese violet; ultramarine blue; chromium oxide, chromium hydrate; ferric blue; and mixtures thereof. In some embodiments, the at least one inorganic pigment comprises a mixture of iron oxides, such as a mixture of red iron oxide, yellow iron oxide, and black iron oxide.

[0048] In one embodiment, the at least one inorganic pigment comprises iron oxide and at least one of zinc oxide and titanium dioxide, and in one embodiment, the at least one inorganic pigment comprises iron oxide and titanium dioxide. Traditional nano-sized particles of inorganic UV filters such as titanium dioxide and zinc oxide can act to provide UVB protection against radiation in the range of about 280 nm to about 320 nm, but these agents often fail to provide sufficient protection against erythema at higher radiation wavelengths that constitute UVA radiation, such as about 315 nm to about 400 nm, including about 375 nm to about 400 nm. On the other hand, as disclosed herein, the addition of at least one inorganic pigment such as iron oxide, titanium dioxide and / or zinc oxide can provide enhanced protection against erythema against UVA radiation and / or visible light, such as protection from UVA radiation in the range of about 375 nm to about 400 nm and visible light in the range of about 400 nm to about 750 nm.

[0049] In embodiments in which the at least one inorganic pigment comprises titanium dioxide and / or zinc oxide, the titanium dioxide and / or zinc oxide may have a larger particle size than the titanium dioxide and / or zinc oxide comprising the UV filter agent. Smaller nano-sized particles of titanium dioxide and / or zinc oxide are known to provide broad spectrum UV filtering and absorbing properties, but have a lower ability to scatter and reflect visible light, making the nano-sized particles more transparent when applied to the skin in the form of a sunscreen composition. See, e.g., Yin, H. et al., A comparative study of the physical and chemical properties of nano-sized ZnO particles from multiple batches of three commercial products, J. Nanopart. Res. 2015;17:1-19.

[0050] Thus, in some embodiments where the sunscreen compositions disclosed herein include nanoparticle zinc oxide and / or nanoparticle titanium dioxide UV filters, the sunscreen compositions may further include at least one inorganic pigment selected from the group consisting of pigmentary zinc oxide and pigmentary titanium dioxide. By "pigmentary" or "pigmentary size" it is meant that the average particle size of the titanium dioxide and / or zinc oxide is larger than the nano-sized particles and is of a size that is cosmetically acceptable for use as a pigment in the sunscreen composition. In some embodiments, the pigmentary particles of zinc oxide may have an average particle size ranging from at least about 100 nm to about 25 μm, such as from about 200 nm to about 10 μm, from about 200 nm to about 500 nm, or from about 5 μm to about 15 μm. In some embodiments, the pigment-sized particles of titanium dioxide can have an average particle size ranging from at least about 100 nm to about 25 μm, such as from about 200 nm to about 10 μm, from about 200 nm to about 500 nm, from about 5 μm to about 15 μm, or from about 8 μm to about 10 μm.

[0051] The at least one inorganic pigment, alone or with other components of the sunscreen composition, can be present in the sunscreen composition in any amount effective to absorb visible light, such as visible light in the blue and / or violet regions of the visible light spectrum. In some embodiments, the at least one inorganic pigment is present in the sunscreen composition in an amount ranging from about 0.01% to about 10%, such as from about 1% to about 5%, or from about 1% to about 4.5%, by weight, based on the total weight of the sunscreen composition.

[0052] In some embodiments, the at least one inorganic pigment may be a surface-treated inorganic pigment. Surface treating the at least one inorganic pigment may reduce or prevent the optical reactivity of the pigment and / or aid in mixing with other ingredients in the sunscreen composition. Surface-treated inorganic pigment indicates that the inorganic pigment is surface-treated by any means including chemical, electrical and / or mechanical means. In some embodiments, surface treating the at least one inorganic pigment may enhance the water-resistant properties of the inorganic pigment and the sunscreen composition. In some embodiments, all of the inorganic pigments present in the sunscreen composition are surface-treated.

[0053] The inorganic pigment can be surface-treated by any surface treatment method or agent known in the art. In some embodiments, at least one inorganic pigment can comprise coated particles. The coating can comprise hydrophobic materials such as alkylsiloxanes (e.g., triethoxycaprylylsilane), organic titanates, halogenated phosphates (e.g., perfluoroalkylphosphonates), halogenated organic silanes, modified amino acids (e.g., disodium stearoyl glutamate), silicones, or metal salts of fatty acids.

[0054] Exemplary embodiments of inorganic pigments may include surface-treated coated inorganic pigments such as coated iron oxides including triethoxycaprylylsilane iron oxide (e.g., Unipure®) and coated and uncoated titanium dioxide (e.g., Unipure® White LC 987 and Unipure® White LC 987 AS-EM, triethoxycaprylylsilane titanium dioxide).

[0055] Antioxidants In some embodiments disclosed herein, the sunscreen composition further comprises at least one antioxidant. Without being bound by theory, it is believed that the at least one antioxidant quenches free radicals induced by the sun's visible light radiation, thereby effectively preventing or reducing sunburn when topically applied to a user in an amount effective to quench the free radicals. In some embodiments, the at least one antioxidant may be selected from vitamin A, vitamin C, vitamin E, selenium, carotenoids (e.g., beta-carotene), thiols, and derivatives and mixtures thereof. In some embodiments, the at least one antioxidant is vitamin E (e.g., tocopherol) or a derivative thereof, such as tocopherol acetate. In some embodiments, the at least one antioxidant is vitamin C (e.g., ascorbic acid) or a derivative thereof, such as tetrahexyldecyl ascorbate. In some aspects of the present disclosure, the at least one antioxidant comprises both vitamin E or a derivative thereof and vitamin C or a derivative thereof.

[0056] At least one antioxidant may be present in the sunscreen compositions disclosed herein in any amount effective to prevent or reduce sunburn caused by the visible light region of the electromagnetic spectrum (e.g., about 400-750 nm), alone or with other components of the sunscreen composition. In some embodiments, vitamin C or a derivative thereof, such as tetrahexyldecyl ascorbate, is present in the sunscreen composition in an amount ranging from about 0.01% to about 5%, such as about 0.1% to about 3%, about 0.2% to about 2%, or about 0.2% to about 1%, by weight, based on the total weight of the sunscreen composition. In some embodiments, vitamin E or a derivative thereof, such as tocopherol acetate, is present in the sunscreen composition in an amount ranging from about 0.01% to about 5%, such as about 0.1% to about 3%, about 0.2% to about 2%, or about 0.2% to about 1%, by weight, based on the total weight of the sunscreen composition. In one embodiment, the at least one antioxidant is a combination of vitamin C or a derivative thereof and vitamin E or a derivative thereof and is present in the sunscreen composition in an amount ranging from about 0.1% to about 10%, such as from about 0.2% to about 5%, from about 0.5% to about 4%, or from about 0.4% to about 2%, by weight based on the total weight of the sunscreen composition.

[0057] Additional ingredients The sunscreen composition of the present disclosure may include any other additional ingredients known in the art to be cosmetically acceptable for use in topical sunscreen products. For example, in some embodiments, the sunscreen composition disclosed herein may further include at least one of cosmetically acceptable carriers such as emollients / oils, emulsifiers, SPF boosters, organic pigments, organic UV filters, skin conditioners, film formers, fillers, preservatives, fragrances, silica, sodium chloride, citric acid, neutralizing agents or pH adjusters (e.g., triethanolamine and sodium hydroxide), essential oils, and water.

[0058] In some embodiments, the sunscreen composition further comprises at least one organic UV filter, and in some embodiments, the sunscreen composition does not comprise an organic UV filter, such that the only UV filter in the sunscreen composition is an inorganic UV filter. Although any organic UV filter known in the art may be considered within the scope of the embodiments disclosed herein, traditional organic UV filters are small aromatic molecules. For example, the at least one organic UV filter disclosed herein may be benzophenones (such as benzophenone-3, benzophenone-5 and benzophenone-8), 3-benzylidene camphor, bisethylhexyloxyphenol methoxyphenyl triazine, butyl methoxydibenzoylmethane, camphor benzalkonium methosulfate, diethylamino hydroxybenzoyl hexyl benzoate, diethylhexyl butamido triazone, drometrizole trisiloxane, ethoxyethyl methoxycinnamate, ethylhexyl

[0043] The amine may be selected from dimethylaminobenzoate, ethylhexyl methoxycinnamate, ethylhexyl salicylate, ethylhexyl triazone, homosalate, isoamyl p-methoxycinnamate, methyl anthranilate, 4-methylbenzylidene camphor, methylene bis-benzotriazolyl tetramethylbutylphenol, octocrylene, para-aminobenzoic acid (PABA), polyacrylamidomethyl benzylidene camphor, polysilicone-15, triethanolamine salicylate and terephthalidene dicamphor sulfonic acid.

[0059] In some embodiments, the sunscreen composition further comprises at least one humectant, such as, for example, butylene glycol or glycerin.

[0060] In some embodiments, the composition may include at least one emollient. Suitable emollients may be selected from any emollient known in the art, including, for example, mineral oil, petroleum oil, vegetable / plant oil such as triglyceride (e.g., caprylic / capric triglyceride), wax (e.g., beeswax), isopropyl palmitate, isopropyl myristate, diisopropyl adipate, dibutyl adipate, butyroctyl salicylate, C12-C15 alkyl benzoate, silicone oil (e.g., dimethicone and stearyl dimethicone), animal oil, hydrocarbon oil, and fatty acid. By way of example, the at least one emollient may be selected from alkane oils such as isododecane and isohexadecane, ester oils, ether oils (e.g., dicaprylyl ether), and artificial triglycerides (e.g., caprylcaprylyl glyceride, glyceryl trimyristate, glyceryl tripalmitate, glyceryl trilinoleate, glyceryl trilaurate, glyceryl tricaprate, glyceryl tricaprylate, capric / caprylic triglyceride, capric / caprylic / linolenic triglyceride, and mixtures thereof).

[0061] Exemplary ester oils include, for example, ethyl palmitate; ethylhexyl palmitate; isopropyl palmitate; dicaprylyl carbonate; alkyl myristates, such as isopropyl myristate and ethyl myristate; isocetyl stearate; 2-ethylhexyl isononanoate; isononyl isononanoate; isodecyl neopentanoate; isostearyl neopentanoate; diethyl sebacate; isopropyl lauroyl sarcosinate; diisopropyl sebacate; bis(2-ethylhexyl) sebacate; diisopropyl adipate; di-n-propyl adipate; dioctyl adipate; bis(2-ethylhexyl) adipate; diisostearyl adipate; bis(2-ethylhexyl) maleate; triisopropyl citrate; triisocetyl citrate; triisostearyl citrate; glyceryl trilactate; glyceryl trioctanoate. aryl; trioctyldodecyl citrate; trioleyl citrate; neopentyl glycol diheptanoate; diethylene glycol diisononanoate; diisopropyl adipate; dioctyl adipate; 2-ethylhexyl hexanoate; ethyl laurate; cetyl octanoate; octyldodecyl octanoate; myristyl propionate; 2-ethylhexyl 2-ethylhexanoate; 2-ethylhexyl octanoate; 2-ethylhexyl caprylate / caprate; methyl palmitate; isononyl isononanoate; isohexyl laurate; hexyl laurate; isopropyl isostearate; isodecyl oleate; glyceryl tri(2-ethylhexanoate); pentaerythrityl tetra(2-ethylhexanoate); 2-ethylhexyl succinate; C10-30 cholesterol / lanosterol esters; and mixtures thereof.

[0062] In some embodiments, the sunscreen composition may further comprise at least one SPF booster. An SPF booster is a compound that acts to increase the UV absorption capacity of other compounds, such as UV filters, by refracting UV radiation (when both compounds are present). The SPF booster may increase the path length of UV radiation as it passes through the sunscreen composition. The at least one SPF booster may be selected from any SPF booster known in the art, including, for example, diethylhexyl syringylidene malonate; glass microspheres such as calcium aluminum borosilicate, sodium borosilicate and calcium / sodium borosilicate; and copolymers of styrene and (meth)acrylic acid.

[0063] In some embodiments, the sunscreen composition may further comprise at least one preservative. Suitable preservatives may include, but are not limited to, chlorophenesin, sorbic acid, disodium ethylenedinitrilotetraacetate, ethylhexylglycerin, phenoxyethanol, methylparaben, ethylparaben, propylparaben, phytic acid, imidazolidinyl urea, sodium dehydroacetate, benzyl alcohol, sodium benzoate, methylchloroisothiazolinone, methylisothiazolinone, and mixtures thereof.

[0064] In some embodiments, the sunscreen composition may further comprise at least one skin conditioning agent, which in some embodiments may also function as a film former and / or emulsifier. Suitable skin conditioning agents include, but are not limited to, glycerin, such as ethoxylated glycerin and propoxylated glycerin; sugar alcohols, such as propylene glycol, dipropylene glycol, butylene glycol, hexylene glycol, pentylene glycol, polypropylene glycol, polyethylene glycol, caprylyl glycol, sorbitol, hydroxypropyl sorbitol, erythritol, threitol, pentaerythritol, xylitol, glucitol, and mannitol; hexanetriol (e.g., 1,2,6-hexanetriol); glyceryl stearate; dimethicone; cyclomethicone; phenyl trimethicone; phenyl dimethicone; cetyl dimethicone; stearyl dimethicone; caprylyl methicone; amodimethicone; C30-45 alkyl dimethicone and methicone; cetearyl methicone; dimethicone copolyol; cyclopentasiloxane (Bentone Gel®, etc.);Dimethicone Crosspolymer;Dimethicone / Vinyl Dimethicone Crosspolymer;C30-45 Alkyl Cetearyl Dimethicone Crosspolymer;Cetearyl Dimethicone Crosspolymer;Dimethicone / Phenyl Vinyl Dimethicone Crosspolymer;Vinyl Dimethicone / Lauryl Dimethicone Crosspolymer;Trifluoropropyl Dimethicone / Trifluoropropyl Divinyl Dimethicone Crosspolymer;Trimethylsiloxysilicate;Trisiloxane;Neopentyl Glycol Diheptanoate;Neopentyl Diethylhexanoate glycol; neopentyl glycol dicaprylate / dicaprate; neopentyl glycol diglycidyl ether; neopentyl glycol dicaprate; neopentyl glycol diisostearate; butyloctyl salicylate; ethylhexyl stearate; diethylhexyl 2,6-naphthalate; petrolatum, beeswax, shea butter, shea oil, cocoa butter, jojoba butter, aloe butter, olive butter, coconut oil, jojoba oil, olive oil, sunflower seed oil, and mixtures thereof.

[0065] In some embodiments, the sunscreen composition may further comprise at least one film former. Suitable film formers may include, but are not limited to, polyurethanes, acrylate / dimethicone crosspolymers, waxes, silicone acrylates, and mixtures thereof.

[0066] The sunscreen compositions disclosed herein may be prepared by any means known in the art, such as by mixing and blending the ingredients of the composition in any manner acceptable in the art. In some embodiments, the sunscreen compositions may be prepared by combining the ingredients with a commercially available topical carrier, which may include other ingredients dissolved or dispersed therein, such as, for example, film formers, surfactants, emulsifiers, thickeners, emollients, preservatives, pH adjusters, colorants, and fragrances.

[0067] Method of Using the Sunscreen Composition Also disclosed herein are methods for reducing or preventing sunburn. The methods disclosed herein may comprise topically applying an effective amount of a sunscreen composition as disclosed herein to a surface of a user's body, such as, for example, the hair, skin, nails, or lips. As used herein, an effective amount may be any amount that reduces or prevents sunburn from exposure to both UV radiation and visible light. In some embodiments, an effective amount is, for example, about 1 mg / cm. 2 ~about 3mg / cm 2 etc., about 0.5 mg / cm 2 ~about 5mg / cm 2 or about 2 mg / cm 2 In some embodiments, the methods disclosed herein further comprise drying the sunscreen composition after application. In some embodiments, the sunscreen will be allowed to dry for a period ranging from about 5 minutes to about 30 minutes, such as about 10 minutes, about 15 minutes, about 20 minutes, or about 25 minutes.

[0068] By topically applying the sunscreen composition, it is understood to mean that the sunscreen composition may be applied to any surface of the user, including, for example, the skin, hair, nails, and / or lips. The sunscreen composition may be topically applied in any manner known in the art, including spray application, wiping, applying, spreading, or rubbing with the hand or an applicator such as a spray bottle, wipe, roller, and the like.

[0069] Also disclosed herein is a method for increasing the SPF of a sunscreen composition, comprising adding at least one inorganic pigment and at least one antioxidant to the sunscreen composition. SPF, or sun protection factor, may be measured as described herein by any means known in the art. In one embodiment, SPF may be measured by the protocol described in International Organization for Standardization (ISO) 24444:2019, which measures SPF in an indoor laboratory in terms of the ratio of the amount of UV radiation required to produce erythema on sunscreen-protected skin to the amount of UV radiation required to produce erythema on unprotected skin. The standard described in ISO 24444:2019 defines SPF in terms of UV radiation (i.e., below 400 nm), and therefore does not take into account, and in fact excludes, the effects of real-life sunlight exposure, including the effects of visible light. In fact, laboratory-based SPF testing typically uses sun simulators that emit UV radiation only in the 290-400 nm region of the spectrum, with added filters to eliminate radiation below 290 nm and above 400 nm, greatly reducing the 380-400 nm content. Thus, the effects of long wavelength UVA and visible light on the skin are not considered in many SPF measurements, including indoor laboratory-based SPF measurements used in many commercial sunscreen products.

[0070] In various embodiments of the methods disclosed herein, the SPF is measured based on actual outdoor sun exposure and can be defined in terms of the ratio of the minimum amount of sun exposure required to produce erythema on sunscreen-protected skin to the amount of sun exposure required to produce erythema on unprotected skin. Thus, the SPF used herein takes into account all of the effects of actual outdoor sun exposure, including both UV radiation and visible light, and represents the performance of the product under actual use conditions.

[0071] In various embodiments of the present disclosure, the SPF of the sunscreens disclosed herein may be increased by at least about 3, such as at least about 4, at least about 5, or at least about 6, when tested under outdoor sunlight exposure conditions, compared to sunscreen compositions that do not contain an effective amount of at least one antioxidant and / or an effective amount of at least one inorganic pigment. In some embodiments, the SPF of the sunscreens disclosed herein may be increased by an SPF ranging from about 2 to about 10, such as from about 3 to about 5 or from about 3 to about 4, when tested under outdoor sunlight exposure conditions. While this level of increase may seem small relative to SPF claims generated by indoor sunlight simulator test methods, in reality, the impact is proportionately higher when comparing products tested in outdoor conditions where the maximum observed SPF value ranges from 8 to 10 to sunscreens claiming SPF 60 to 100. Thus, an increase of 2 to 6 SPF units over the maximum observed result of 8 to 10 in this outdoor use condition represents a significant increase in real-world protection.

[0072] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the present disclosure are approximations, the numerical values ​​set forth in the specific examples are reported as precisely as possible, however, any numerical value inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Moreover, all ranges disclosed herein should be understood to encompass any and all subranges subsumed therein.

[0073] Although the present teachings have been described with respect to one or more embodiments, modifications and / or variations may be made to the described examples without departing from the spirit and scope of the following claims. Moreover, although a particular feature of the present teachings has been disclosed with respect to only one of several embodiments, such feature may be combined with one or more other features of other embodiments as may be desired and advantageous for any given or specific function. Furthermore, the terms "including," "includes," "having," "has," "with," or variations thereof, to the extent that they are used in the detailed description and claims, are inclusive in the same manner as the term "comprising." Also, in the description and claims herein, the term "about" indicates that the recited value may be somewhat altered as long as such alteration does not result in incompatibility of the processing or structure of the described embodiment. Finally, "exemplary" indicates that the description is used as an example, and not as an indication that the description is ideal.

[0074] It will be appreciated that variations or alternatives of the above-disclosed and other features and functions may be combined into many other different systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may subsequently occur to those skilled in the art, and are intended to be encompassed by the following claims. EXAMPLES

[0075] The sunscreen compositions were formulated as shown in Table 1 below.

[0076] Table 1 - Sunscreen formulations for GM1, GM2 and GM3 [Table 1]

[0077] Table 1 provides a formulation for a sunscreen according to the present disclosure (GM1) and two comparative formulations (GM2 and GM3) that were formulated for a clinical trial in late November in Arequipa, Peru, from 10:00 am to 12:30 pm local time (11:00 am noon). The GM2 "placebo" formulation contains ingredients for a conventional sunscreen product with 10% micron titanium dioxide and 11% micron zinc oxide, but no antioxidants Vitamin E or Vitamin C or inorganic pigment iron oxide. GM3 is also a conventional sunscreen, further including antioxidants in the formulation at 1% by weight each, but no iron oxide. The GM1 formulation adds both antioxidants and iron oxides (yellow, black, and red iron oxides) in ratios that match skin color. Although the percentages of titanium dioxide and zinc oxide were very small in the formulas due to the addition of iron oxide and antioxidant additives, the actual amounts of titanium dioxide and zinc oxide in each batch were the same after adjusting for the emollient concentrations.

[0078] The three formulations and the ISO reference standard SPF 63 formulation (containing no visible light protection and no iron oxides or antioxidants) were tested on 11 subjects for SPF values ​​during outdoor natural sun exposure near the solstice at approximately 7500 feet altitude in Arequipa, Peru. The tanning UV intensity ranged from 7.5 to 8 sunburn doses per hour during this period (i.e., approximately 7.5 to 8 minutes of exposure was required to produce sunburn). This is a high intensity UV environment compared to the usual exposure time of 15 to 20 minutes for sunburn in North America or Europe. The high sun angle (zenith angle 87°) combined with the higher altitude resulted in the greatest UV content relative to the visible light content.

[0079] The three sunscreen formulations were tested at 2 mg / cm2 SPF as specified by a recognized SPF testing protocol. 2The test subjects were applied to a rectangular area on their backs at a density of 1000 mg / kg / day. The product was covered and allowed to dry for at least 15 minutes. The test area was surrounded by aluminum foil tape and exposed to sunlight with varying amounts of UV exposure as measured by a suntan UV dosimeter. Once the desired exposure was reached, the relevant test area was covered with aluminum foil tape and exposure to that area was stopped. Exposures were also administered to areas without sunscreen to measure the minimum unprotected dose of radiation that would cause sunburn. At the end of all exposures, the subjects' exposed back areas were covered and the subjects were instructed to enter the shade and keep their backs completely covered for the remainder of the day.

[0080] The following monitoring (approximately 16-24 hours after exposure) was performed to examine the exposed areas of the subjects and determine the so-called minimal erythema dose (MED), the lowest dose of exposure that causes a sunburn reaction, for both sunscreen protected and unprotected areas. The ratio of doses (sunscreen protected dose / unprotected dose) was calculated as the SPF value of the test product (as is done in traditional laboratory SPF testing). The protection values ​​were then compared for each of the four test products GM1, GM2, GM3 and the SPF63 reference product. The calculated SPFs for each of the sunscreen formulations tested are shown in Table 2 below.

[0081] Table 2 - Natural sunlight SPF values ​​for GM1 to GM3 and SPF63 reference [Table 2]

[0082] These data demonstrated that the formulation with the addition of antioxidants (GM3) gave additional protection in SPF (i.e., 8.8 vs. 8.1) compared to the formulation without antioxidants (GM2), with a p-value of p<0.08. The addition of iron oxide to the formulation together with antioxidants (GM1) increased the SPF value to 11.9, a significant difference compared to 8.1 for GM2 (p<0.001). The SPF63·ISO reference standard without visible light protection only showed an SPF of 8.5 instead of the expected SPF of 63 as tested in the clinical SPF testing laboratory. The discrepancy between these two results can be attributed to the fact that the sun simulator used in the clinical SPF test does not contain visible light - it is excluded (by design) from the spectral output of the simulator to reduce potential thermal load on the skin during testing. Therefore, the discrepancy between the SPF63 obtained in the clinical SPF test and the value of 8.5 measured under natural sunlight at optimal UV content is mainly due to the presence of visible light in the test light source. The sunscreen GM1 of the present invention, when tested outdoors in real sunlight with a real solar spectrum including visible light, is surprisingly far superior to the SPF 63 reference sunscreen (p<0.003), due to the fact that GM1 provides the missing protection in the visible part of the spectrum by iron oxides and antioxidants.

[0083] If only 10% of the erythemal damage of sunlight is caused by visible light, this would be enough to reduce the protection of an SPF 63 sunscreen (1.6% transmission) to 8.6 (11.6% transmission), explaining the failure of this sunscreen in real-world sun testing. Similar findings of failure of high SPF products when tested in natural sunlight have been reported in the art. See, e.g., Lott, D., Testing SPF 15-100, Indoor v. Outdoor, Cosmet. & Toil. 2013; 128(9): 638-647 and Hughes, SNG et al., Assessment of Natural Sunlight Protection Provided by 10 High SPF Broad Spectrum Sunscreens and Sun Protective Fabrics, Curr. Probl. Dermatol. 2021; 55 (in press). EXAMPLES

[0084] Additional sunscreen formulations were prepared containing tocopherol instead of tocopherol acetate in combination with the vitamin C derivative tetrahexyldecyl ascorbate, iron oxide, titanium dioxide and zinc oxide for UV protection. The formulations are shown in Table 3 below.

[0085] Table 3 - Tinted sunscreen moisturizer [Table 3]

[0086] The formulation resulted in a beige lotion that provided excellent protection against sunburn and a pleasant color and feel after application to the skin. The lotion was evaluated to determine its critical wavelength by in vitro UVA broad spectrum testing according to the protocol described in FDA Final Rule Docket No. FDA-1978-N-0018, entitled "Labeling and Effectiveness testing; Sunscreen Drug Products for Over-the-Counter Human Use." The critical wavelength was measured using a LS1000-6S-009 Labsphere Ultraviolet Transmittance Analyzer (Spectrometer); a Solar Light PMA 2101 Erythema Weighted Detector; and HD6 PMMA plates.

[0087] Five readings of three plates were performed. The critical wavelengths for the three test samples were 374.20, 373.20 and 373.00 (average 373.47 nm). The average UVA / UV ratio was 0.64 and the average UVA / UVB ratio was 0.49. The results are shown in Table 4 below.

[0088] Table 4 - Critical Wavelength Testing of Three Samples of Formulations [Table 4]

Claims

1. 1. A sunscreen composition for use in a method for reducing or preventing sunburn caused by visible and ultraviolet (UV) radiation in a subject, comprising: (a) inorganic UV filters comprising zinc oxide and titanium dioxide present in the sunscreen composition in a total amount ranging from about 10% to about 50% by weight, based on the total weight of the sunscreen composition; (b) at least one antioxidant present in the sunscreen composition in a total amount ranging from about 0.1% to about 5% by weight, based on the total weight of the sunscreen composition; (c) at least one inorganic pigment comprising iron oxide present in the sunscreen composition in a total amount ranging from about 0.1% to about 10% by weight, based on the total weight of the sunscreen composition; A sunscreen composition, wherein the at least one inorganic pigment and the at least one antioxidant are present in amounts effective to reduce or prevent sunburn caused by visible light.

2. 10. The sunscreen composition of claim 1, wherein the iron oxide is selected from the group consisting of black iron oxide, brown iron oxide, red iron oxide, yellow iron oxide, and mixtures thereof.

3. 10. The sunscreen composition of claim 1, wherein the zinc oxide has an average particle size ranging from about 10 nm to about 100 nm.

4. 10. The sunscreen composition of claim 1, wherein the titanium dioxide has an average particle size ranging from about 5 nm to about 20 nm.

5. 10. The sunscreen composition of claim 1, wherein at least one of the zinc oxide, the titanium dioxide, and the iron oxide further comprises a coating.

6. 6. The sunscreen composition of claim 5, wherein the coating is triethoxycaprylylsilane.

7. The sunscreen composition of claim 1, wherein the at least one antioxidant is selected from vitamin A, vitamin C, vitamin E, selenium, carotenoids, thiols, or derivatives and mixtures thereof.

8. 8. The sunscreen composition according to claim 7, wherein the vitamin C or a derivative thereof is selected from the group consisting of ascorbic acid and tetrahexyldecyl ascorbate, and / or the vitamin E or a derivative thereof is selected from the group consisting of tocopherol and tocopheryl acetate.

9. 10. The sunscreen composition of claim 1, wherein the at least one inorganic pigment further comprises at least one inorganic pigment selected from the group consisting of pigmentary zinc oxide and pigmentary titanium dioxide.

10. 10. The sunscreen composition of claim 9, wherein the pigment titanium dioxide has an average particle size ranging from about 1 μm to about 20 μm.

11. 1. A method for increasing the sun protection factor (SPF) of a sunscreen composition containing inorganic UV filters, including zinc oxide and titanium dioxide, comprising: adding to the sunscreen composition: (a) at least one antioxidant present in the sunscreen composition in a total amount ranging from about 0.1% to about 5% by weight, based on the total weight of the sunscreen composition; and (b) at least one inorganic pigment comprising iron oxide present in the sunscreen composition in a total amount ranging from about 0.1% to about 10% by weight, based on the total weight of the sunscreen composition. Equipped with The method, wherein the inorganic pigment and the at least one antioxidant are present in amounts effective to increase the SPF of the sunscreen composition when tested under outdoor sunlight exposure.

12. 12. The method of claim 11, wherein the SPF is increased by at least about an SPF of 3.

13. 12. The method of claim 11, wherein the sunscreen composition is free of organic UV filters.

14. 12. The method of claim 11, wherein the at least one inorganic pigment further comprises at least one inorganic pigment selected from the group consisting of pigmentary titanium dioxide and pigmentary zinc oxide.

15. 12. The method of claim 11, wherein the zinc oxide has an average particle size ranging from about 10 nm to about 100 nm.

16. The method of claim 11, wherein the titanium dioxide has an average particle size ranging from about 5 nm to about 20 nm.

17. The method of claim 11, wherein the at least one antioxidant is selected from vitamin A, vitamin C, vitamin E, selenium, carotenoids, thiols or derivatives and mixtures thereof.

18. 18. The method of claim 17, wherein the vitamin C or a derivative thereof is selected from the group consisting of ascorbic acid and tetrahexyldecyl ascorbate, and / or the vitamin E or a derivative thereof is selected from the group consisting of tocopherol and tocopherol acetate.

19. 15. The method of claim 14, wherein the pigmentary titanium dioxide has an average particle size ranging from about 1 μm to about 20 μm.

20. 1. A sunscreen composition comprising: (a) inorganic UV filters consisting of zinc oxide and titanium dioxide present in the sunscreen composition in a total amount ranging from about 10% to about 50% by weight, based on the total weight of the sunscreen composition; (b) at least one antioxidant present in the sunscreen composition in a total amount ranging from about 0.1% to about 5% by weight, based on the total weight of the sunscreen composition; (c) an inorganic pigment comprising iron oxide present in the sunscreen composition in a total amount ranging from about 0.1% to about 10% by weight, based on the total weight of the sunscreen composition; Including, A sunscreen composition wherein the inorganic pigment and the at least one antioxidant are present in amounts effective to reduce or prevent sunburn caused by visible light.