Ultraviolet-blocking cosmetic composition containing dispersion with high zinc oxide content

Abstract

The present invention relates to an ultraviolet-blocking cosmetic composition, wherein the cosmetic composition contains zinc oxide stabilized in a formulation through a zinc oxide dispersion, and thus exhibits excellent formulation stability and adhesion, low white turbidity, and superior ultraviolet-blocking performance. Specifically, the present invention relates to an ultraviolet-blocking cosmetic composition, wherein the cosmetic composition exhibits low white turbidity and exerts high ultraviolet-blocking ability by optimizing a dispersion containing ultra-high-content zinc oxide particles through mixing with an emulsifier and a dispersant.

Description

UV protection cosmetic composition containing a high concentration of zinc oxide dispersion

[0001] The present invention relates to a cosmetic composition for sunscreen containing a zinc oxide dispersion, and specifically, to a cosmetic composition for sunscreen that has excellent sunscreen performance and low white cast by stably incorporating zinc oxide at an ultra-high content within the formulation using a zinc oxide dispersion, an emulsifier, and a dispersant.

[0002] Electromagnetic waves can be classified into infrared, visible light, and ultraviolet rays depending on their wavelength. Among these, ultraviolet rays, which are exposed through sunlight, have short wavelengths and high energy, and even short-term exposure can cause phenomena such as skin aging and wrinkles. Ultraviolet A (UVA; ultraviolet rays in the wavelength range of 320 to 400 nm), classified as long-wavelength ultraviolet rays, can reach the dermis layer of the skin and is known to cause tanning and long-term skin damage associated with aging, while ultraviolet B (UVB; ultraviolet rays in the wavelength range of 280 to 320 nm) causes tanning and skin cancer. Ultraviolet C (UVC; ultraviolet rays in the wavelength range of less than 280 nm), the shortest wavelength ultraviolet rays, is completely absorbed by the ozone layer, so the amount reaching the Earth's surface is very small; however, it is known to cause burns, skin cancer, and cataracts upon human exposure.

[0003] Currently, sunscreens designed to block ultraviolet rays are classified as functional cosmetics, and sunscreen products with various SPF (Sun Protection Factor) levels are being released. Generally, in order to achieve high SPF values, inorganic sunscreens such as titanium oxide and zinc oxide, or organic sunscreens such as ethylhexyl salicylate, are used in sunscreen products.

[0004] Zinc oxide is a representative inorganic sunscreen that exhibits UV blocking effects through UV absorption and scattering. It has a high refractive index, is non-toxic to the human body, and has the characteristic of simultaneously blocking UV-A (320–400 nm) and UV-B (280–320 nm) UV rays contained in sunlight, so its use is gradually increasing.

[0005] However, despite these benefits, zinc oxide has strong inter-particle cohesiveness, so it exhibits a rough texture when applied to the skin, resulting in a stiff feel when used in cosmetics. Additionally, the high whiteness of zinc oxide causes a white cast on the skin, which limits its usage content when applied as a cosmetic ingredient.

[0006] Accordingly, the inventors continued research on a method to disperse zinc oxide in a high concentration within a formulation, and as a result, optimized a zinc oxide dispersion dispersed using polyhydroxystearic acid using an emulsifier and a dispersant to stably incorporate an ultra-high concentration of zinc oxide into the formulation, thereby developing a cosmetic composition for UV protection that has excellent UV blocking performance and improved whitening phenomenon.

[0007] The present invention aims to provide a cosmetic composition for UV protection that exhibits excellent UV protection efficacy and improves the whitening phenomenon by utilizing a zinc oxide dispersion in which zinc oxide is stably dispersed.

[0008] The technical problems of the present invention are not limited to those mentioned above, and other unmentioned technical problems will be clearly understood by those skilled in the art from the description below.

[0009] According to an embodiment of the present invention, a cosmetic composition for blocking ultraviolet rays is provided, comprising a zinc oxide dispersion, a first emulsifier, a second emulsifier, and a dispersant, wherein the zinc oxide dispersion is obtained by dispersing zinc oxide using polyhydroxystearic acid.

[0010] The cosmetic composition for UV protection according to the present invention optimizes the zinc oxide dispersion so that a high content of zinc oxide powder is stabilized within the formulation in a highly dispersible state, thereby enabling excellent UV protection efficacy with low turbidity.

[0011] In addition, since the UV-blocking cosmetic composition according to the present invention contains a high amount of zinc oxide, the amount of zinc oxide dispersion used can be reduced compared to existing dispersions, thereby increasing the amount of texture modifiers, oils, or functional ingredients to improve the efficacy and texture of the cosmetic.

[0012] In addition, as the zinc oxide dispersion is stably dispersed within the formulation, formulation stability is improved, and adhesion is enhanced when applied to the skin, providing an excellent user experience.

[0013] A brief description of each drawing is provided to help to better understand the drawings cited in the detailed description of the invention.

[0014] Figure 1 shows a photograph of a PMMA plate coated with the cosmetic compositions of Example 1 and Comparative Example 1 after a turbidity evaluation experiment.

[0015] Figure 2 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Example 1.

[0016] Figure 3 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 1.

[0017] Figure 4 shows photographs of PMMA plates coated with the cosmetic compositions of Comparative Examples 2 to 4 after the turbidity evaluation experiment.

[0018] Figure 5 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 2.

[0019] Figure 6 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 3.

[0020] Figure 7 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 4.

[0021] Figure 8 shows a photograph of a PMMA plate coated with the cosmetic compositions of Examples 2 and 3 after a turbidity evaluation experiment.

[0022] FIG. 9 shows photographs of PMMA plates coated with the cosmetic compositions of Comparative Examples 5 to 7 after the turbidity evaluation experiment.

[0023] Figure 10 shows photographs of PMMA plates coated with the cosmetic compositions of Comparative Examples 8 and 9 after the turbidity evaluation experiment.

[0024] Figure 11 shows photographs of PMMA plates coated with the cosmetic compositions of Comparative Examples 10 to 11 after a turbidity evaluation experiment.

[0025] Figure 12 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Example 2.

[0026] Figure 13 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Example 3.

[0027] Figure 14 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 5.

[0028] Figure 15 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 6.

[0029] Figure 16 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 7.

[0030] Figure 17 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 8.

[0031] Figure 18 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 9.

[0032] Figure 19 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 10.

[0033] Figure 20 shows the results of the evaluation of the UV blocking efficacy of the cosmetic composition of Comparative Example 11.

[0034] According to an embodiment of the present invention, a cosmetic composition for blocking ultraviolet rays is provided, comprising a zinc oxide dispersion, a first emulsifier, a second emulsifier, and a dispersant, wherein the zinc oxide dispersion is obtained by dispersing zinc oxide using polyhydroxystearic acid.

[0035] The zinc oxide may be included in an amount of 30 to 70 weight percent based on the total weight of the zinc oxide dispersion.

[0036] The above zinc oxide dispersion may include zinc oxide*propyl heptyl caprylate*polyhydroxystearic acid*triethoxycaprylylsilane.

[0037] The zinc oxide dispersion may be included in an amount of 5 to 50 weight% based on the total weight of the cosmetic composition.

[0038] The first and second emulsifiers above may include different polyglyceryl-based emulsifiers.

[0039] The first emulsifier may be included in an amount of 1.1 to 7 weight percent based on the total weight of the cosmetic composition.

[0040] The second emulsifier may be included in an amount of 0.1 to 7 weight percent based on the total weight of the cosmetic composition.

[0041] The first emulsifier and the second emulsifier may be included in a weight ratio of 1:0.14 to 0.9.

[0042] The above dispersant may include polyglyceryl-5 polyricinoleate.

[0043] The above-mentioned dispersant may be included in an amount of 0.1 to 7 weight percent based on the total weight of the cosmetic composition.

[0044] The first emulsifier and the dispersant may be included in a weight ratio of 1:0.14 to 0.9.

[0045] The above second emulsifier and dispersant may be included in a weight ratio of 1:0.2 to 7.

[0046] The first emulsifier, the second emulsifier, and the dispersant may be included in a weight ratio of 1:0.14 to 0.9:0.14 to 0.9.

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by a skilled expert in the art to which the present invention pertains. In general, the nomenclature used herein is well known and commonly used in the art. Furthermore, in describing embodiments of the present invention, detailed descriptions of related known components or functions are omitted if it is determined that such detailed descriptions would hinder understanding of the embodiments of the present invention. Additionally, while embodiments of the present invention will be described below, the technical concept of the present invention is not limited or restricted thereto and can be modified and implemented in various ways by those skilled in the art.

[0048] In this specification, when a part is described as including a certain component, it means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. In this specification, the term "and / or" includes a combination of a plurality of related items or any one of a plurality of related items.

[0049]

[0050] A cosmetic composition for UV protection according to an embodiment of the present invention comprises a zinc oxide dispersion, wherein the zinc oxide dispersion is stabilized by a first emulsifier, a second emulsifier, and a dispersant. The present invention optimally combines the first emulsifier, the second emulsifier, and the dispersant to ensure that a zinc oxide dispersion containing an ultra-high content of zinc oxide is stably dispersed within the cosmetic composition.

[0051] Zinc oxide can be safely used even on sensitive skin and has UV protection efficacy that blocks UV-A and UV-B bands. To improve the UV protection efficacy of zinc oxide, it can be manufactured in a powder form that exhibits a high light-blocking rate using nano-sized particles.

[0052] The zinc oxide used in the zinc oxide dispersion of the present invention may be used in the form of a powder having various particle shapes, specifically having an average particle size of 5 to 100 nm, more specifically having an average particle size of 10 to 90 nm, and even more specifically having an average particle size of 20 to 80 nm, specifically having an aspect ratio of 1 to 5, and more specifically having an aspect ratio of 1 to 3. The size and shape of the zinc oxide powder are not limited thereto.

[0053] Meanwhile, zinc oxide powders have poor dispersion stability due to their fine particle size, and their UV blocking efficacy decreases due to clumping between particles even after dispersion. Therefore, in general, when preparing zinc oxide dispersions, a method is used to stabilize the zinc oxide powder by applying specific surface treatment agents and dispersants to the dispersion medium. However, despite these efforts, dispersions containing high zinc oxide content have not been utilized because aggregation occurs between zinc oxide particles, leading to a decrease in UV blocking ability.

[0054] The zinc oxide dispersion of the present invention uses a specific dispersant to ensure that a high content of zinc oxide is stably dispersed. This zinc oxide dispersion stabilizes the zinc oxide component within the formulation of the cosmetic composition, thereby enabling the effective expression of the UV-blocking efficacy of zinc oxide, which not only improves the UV-blocking efficacy index of the cosmetic composition but also contributes to the improvement of the user experience due to excellent adhesion and low whiteness.

[0055] In preparing the zinc oxide dispersion of the present invention, polyhydroxystearic acid can be added as a dispersant to prepare a dispersion containing a high content of zinc oxide.

[0056] Specifically, in preparing the zinc oxide dispersion of the present invention, the surface is treated using triethoxycaprylylsilane as a zinc oxide surface modifier, and polyhydroxystearic acid is added as a dispersant to prepare a dispersion containing a high content of zinc oxide.

[0057] Polyhydroxystearic acid, as a dispersant, inhibits the aggregation phenomenon between zinc oxide particles and stabilizes zinc oxide, thereby enabling the stable maintenance of a high-content zinc oxide dispersion even after a certain period of time has passed since the formulation was formed.

[0058] In addition, the cosmetic composition for UV protection of the present invention may include zinc oxide*propyl heptyl caprylate*polyhydroxystearic acid*triethoxycaprylylsilane as a zinc oxide dispersion.

[0059] The 'zinc oxide*propyl heptyl caprylate*polyhydroxystearic acid*triethoxycaprylylsilane' of the present invention refers to a zinc oxide dispersion prepared by adding zinc oxide modified with triethoxycaprylylsilane to propyl heptyl caprylate together with polyhydroxystearic acid.

[0060] The above triethoxycaprylylsilane can serve as a surface modifier for zinc oxide, hydrophobizing the surface of zinc oxide to allow the zinc oxide dispersion to be easily dispersed in the oil phase and to suppress aggregation between zinc oxide powders.

[0061] The above-mentioned propylheptyl caprylate acts as a dispersion medium for zinc oxide to enhance the dispersibility of zinc oxide, and can improve the fluidity of the zinc oxide dispersion to provide an excellent user experience.

[0062] In one embodiment, the zinc oxide may be included in an amount of 30 to 70 weight% based on the total weight of the zinc oxide dispersion, specifically in an amount of 50 to 70 weight%, and more specifically in an amount of 60 to 70 weight%, but is not limited thereto.

[0063] The zinc oxide dispersion of the present invention contains a high content of zinc oxide powder, thereby allowing the optimal zinc oxide content to be reached even with a low added content of the zinc oxide dispersion compared to conventional zinc oxide dispersions with low zinc oxide content, and thereby allowing additional addition of functional ingredients that can improve the efficacy or feel of the cosmetic composition.

[0064] In one embodiment, the zinc oxide dispersion may be included in an amount of 5 to 35 weight% based on the total weight of the cosmetic composition, specifically in an amount of 7 to 35 weight%, and more specifically in an amount of 10 to 35 weight%, but is not limited thereto.

[0065] In one embodiment, different polyglyceryl-based emulsifiers may be included as the first emulsifier and the second emulsifier to stabilize the zinc oxide dispersion in the cosmetic composition of the present invention.

[0066]

[0067] In one embodiment, polyglyceryl-3 polydimethylsiloxyethyl dimethicone may be included as the first emulsifier to stabilize the zinc oxide dispersion of the present invention.

[0068] In the present invention, polyglyceryl-3 polydimethylsiloxyethyl dimethicone can stabilize a zinc oxide dispersion to improve the stability of the formulation and improve the adhesion of the cosmetic composition to the skin.

[0069] In one embodiment, the polyglyceryl-3 polydimethylsiloxyethyl dimethicone may be included in an amount of 1.1 to 7 weight% based on the total weight of the cosmetic composition, specifically in an amount of 1.3 to 6 weight%, more specifically in an amount of 1.5 to 5 weight%, and most specifically in an amount of 2 to 4 weight%. If the polyglyceryl-3 polydimethylsiloxyethyl dimethicone is included in an amount of less than 1.1 weight% based on the total weight of the cosmetic composition, it is difficult to form the formulation of the composition and the adhesion may be low when applied to the skin; if it is included in an amount exceeding 7 weight%, the formulation stability decreases and the opacity increases, which may reduce the user experience. However, it is not limited thereto.

[0070] In one embodiment, to stabilize the zinc oxide dispersion of the present invention, lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone may be included as the second emulsifier.

[0071] In the present invention, Lauryl Polyglyceryl-3 Polydimethylsiloxyethyl Dimethicone can stably and evenly disperse zinc oxide dispersions to lower the turbidity of the composition and improve the adhesion of the cosmetic composition to the skin.

[0072] In one embodiment, the lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone may be included in an amount of 0.1 to 7 weight% based on the total weight of the cosmetic composition, specifically in an amount of 0.2 to 5 weight%, more specifically in an amount of 0.3 to 3 weight%, and most specifically in an amount of 0.5 to 1 weight%. If the lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone is included in an amount of less than 0.1 weight% based on the total weight of the cosmetic composition, it may be difficult to form the formulation of the composition or the usability may be reduced, and if it is included in an amount exceeding 7 weight%, formulation stability may decrease and the turbidity may increase, thereby reducing the usability. However, it is not limited thereto.

[0073] In one embodiment, the first emulsifier and the second emulsifier may be included in a weight ratio of 1:0.14 to 0.9, specifically in a weight ratio of 1:0.15 to 0.5, and more specifically in a weight ratio of 1:0.17 to 0.33. When the first emulsifier and the second emulsifier are included in the above weight ratios, the formulation of the composition can be stably formed.

[0074] To stabilize the zinc oxide dispersion of the present invention, polyglyceryl-5 polyricinoleate may be included as the dispersant.

[0075] In the present invention, polyglyceryl-5 polyricinoleate can stably and evenly disperse zinc oxide dispersions, thereby lowering the turbidity of the composition and improving adhesion to the skin.

[0076] In one embodiment, the polyglyceryl-5 polyricinoleate may be included in an amount of 0.1 to 7 weight% based on the total weight of the cosmetic composition, specifically in an amount of 0.2 to 5 weight%, more specifically in an amount of 0.3 to 3 weight%, and most specifically in an amount of 0.5 to 1 weight%. If the polyglyceryl-5 polyricinoleate is included in an amount of less than 0.1 weight% based on the total weight of the cosmetic composition, it may be difficult to form the formulation of the composition or the UV blocking efficacy may be reduced, and the adhesion may decrease, resulting in a reduced user experience; if it is included in an amount exceeding 7 weight%, the formulation stability may decrease and the opacity may increase. However, it is not limited thereto.

[0077] In one embodiment, the first emulsifier and the dispersant may be included in a weight ratio of 1:0.14 to 0.9, specifically in a weight ratio of 1:0.15 to 0.5, and more specifically in a weight ratio of 1:0.17 to 0.33. When the first emulsifier and the dispersant are included in the above weight ratio, the zinc oxide dispersion is stably dispersed, the formulation is stably formed, the turbidity is low, and the adhesion of the cosmetic composition is improved, thereby improving the user experience.

[0078] In one embodiment, the second emulsifier and the dispersant may be included in a weight ratio of 1:0.2 to 7, specifically in a weight ratio of 1:0.3 to 5, and more specifically in a weight ratio of 1:0.5 to 2. When the second emulsifier and the dispersant are included in the above weight ratio, the zinc oxide dispersion is stably dispersed, resulting in low turbidity and improved adhesion of the cosmetic composition, which can improve the user experience.

[0079] As a first emulsifier, a second emulsifier, and a dispersant for stabilizing the zinc oxide dispersion of the present invention, polyglyceryl-3 polydimethylsiloxyethyl dimethicone, lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone, and polyglyceryl-5 polyricinoleate, respectively, may be included.

[0080] In one embodiment, the first emulsifier, the second emulsifier, and the dispersant may be included in a weight ratio of 1:0.14 to 0.9:0.14 to 0.9, specifically in a weight ratio of 1:0.15 to 0.5:0.15 to 0.5, and more specifically in a weight ratio of 1:0.17 to 0.33:0.17 to 0.33. When the first emulsifier, the second emulsifier, and the dispersant are included in such weight ratios, the formulation stability is excellent, the UV blocking efficacy of the cosmetic composition is excellent, the turbidity is low, and the adhesion is improved, thereby improving the user experience.

[0081]

[0082] In one embodiment, the cosmetic composition of the present invention may additionally include at least one of a preservative, a skin conditioning agent, a suspending agent, a bulking agent, and a functional ingredient.

[0083] The above preservative is used to enhance the effect of preservation, and for example, at least one of ethylhexylglycerin, 1,2-hexanediol, caprylyl glycol, phenoxyethanol, and glyceryl caprylate may be used, but is not limited thereto, and any preservative generally used in the industry may be appropriately selected without limitation.

[0084] The above skin conditioning agent is used to enhance the protective and moisturizing effects of the skin, and at least one of propanediol, 2,3-butanediol, propylene glycol, butyloctyl salicylate, caprylyl methicone, methyl trimethicone, propylheptyl caprylate, butylene glycol, pentylene glycol, glycerin, niacinamide, and dipotassium glycyrrhizate may be used, but is not limited thereto; any skin conditioning agent that is generally used in the industry may be appropriately selected without limitation.

[0085] The above-mentioned suspending agent is used to stably disperse solid particles, and for example, at least one of stearalkonium hectorite, quaternium-18 hectorite, and disteadiamonium hectorite may be used, but is not limited thereto, and any suspending agent that can be generally used in the industry may be appropriately selected without limitation.

[0086] The above bulking agent is an inert solid material used to dilute a solid component to increase its volume, and at least one of, for example, hard magnesium carbonate, spherical cellulose, dextrin, magnesium sulfate, magnesium stearate, sodium magnesium silicate, silica, and maltodextrin may be used, but is not limited thereto, and any suspending agent that can be generally used in the industry may be appropriately selected without limitation.

[0087] The above functional ingredients may be added by mixing various ingredients according to the purpose of the cosmetic composition, and include, for example, all of the following: wrinkle improvement agents, whitening functional ingredients, pigmentation functional ingredients, skin soothing functional ingredients, and sebum or pore management functional ingredients.

[0088] In addition to this, the cosmetic composition for ultraviolet light of the present invention may additionally include ingredients included in general cosmetic compositions, for example, polyols, texture modifiers, emulsifying stabilizers, ion chelating agents, disinfectants, pH modifiers, antioxidants, alcohols, plant extracts, fragrances, texture modifiers, emollients, etc.

[0089] The amounts of the aforementioned ingredients are not particularly limited and can be easily selected by a person skilled in the art within a range that does not impair the purpose and effects of the present invention.

[0090]

[0091] The cosmetic composition of the present invention may be provided in formulations commonly manufactured in the art. For example, it may be formulated into emulsion formulations of the type of oil in water (O / W), water in oil (W / O), or water in oil in water (W / O / W), and specifically, it may be formulated into an emulsion formulation of the type of oil in oil (W / O). However, it is not limited thereto, and the composition may also be provided in various formulations such as solution, suspension, emulsion, solid, oil, powder, paste, or foam aerosol, mist, etc.

[0092] The cosmetic composition for sunscreen according to the present invention may be in a liquid, lotion, cream, aerosol, solid, or solid form including powder, and preferably may be a lotion composition. In the present invention, the formulation of the cosmetic composition may include a solution, emulsion, gel, cream, suspension, or paste formulation, but is not limited thereto.

[0093] According to the embodiments, the above-described cosmetic composition for UV protection can be manufactured into various cosmetics having UV protection functions, in addition to UV blockers. For example, it may be formulated into a makeup primer, makeup base, liquid or solid foundation, concealer, blusher, twin cake, compact, cushion, etc., but is not limited thereto.

[0094]

[0095] In the following, examples and experimental examples are presented to further explain the present invention in more detail, but the present invention is not limited thereto.

[0096]

[0097] Experimental Example 1. Comparative experiment according to the type of zinc oxide dispersion component

[0098] To investigate the effect of polyhydroxystearic acid on zinc oxide dispersions, cosmetic compositions for UV protection containing zinc oxide dispersions of the comparative example and the example were prepared, and the efficacy of the formulations was evaluated. The specific preparation method is as follows.

[0099]

[0100] (1) Preparation of zinc oxide dispersion

[0101] Preparation Example 1: Zinc oxide * Propyl heptyl caprylate * Polyhydroxystearic acid * Triethoxycaprylyl silane

[0102] The zinc oxide dispersion of Preparation Example 1 was prepared by adding zinc oxide modified with triethoxycaprylylsilane to propylheptylcaprylate together with polyhydroxystearic acid.

[0103] Here, the zinc oxide dispersion comprises 70% by weight of zinc oxide, 4% by weight of triethoxycaprylylsilane, 2% by weight of polyhydroxystearic acid, and 24% by weight of propylheptylcaprylate.

[0104]

[0105] Preparation Example 2: Zinc oxide * Propyl heptyl caprylate * Triethoxycaprylyl silane

[0106] The zinc oxide dispersion of Preparation Example 2 was prepared by adding zinc oxide modified with triethoxycaprylylsilane to propylheptylcaprylate.

[0107] Here, the zinc oxide dispersion contains 70% by weight of zinc oxide and 24% by weight of propylheptylcaprylate.

[0108]

[0109] (2) Preparation of a cosmetic composition for ultraviolet protection

[0110] Cosmetic compositions of Example 1 and Comparative Example 1 according to the present invention were prepared using the ingredients listed in Table 1 below. Specifically, the composition of Example 1 is a composition comprising zinc oxide*propyl heptyl caprylate*polyhydroxystearic acid*triethoxycaprylylsilane (Preparation Example 1), and the composition of Comparative Example 1 is a composition comprising zinc oxide*propyl heptyl caprylate*triethoxycaprylylsilane (Preparation Example 2). The total content of the zinc oxide dispersion was maintained the same as in Example 1. In Table 1 below, the unit of the content of each ingredient is weight%.

[0111]

[0112] At room temperature, a zinc oxide dispersion was added to an oil phase component containing a skin conditioning agent, an emulsifier, a dispersant, a suspending agent, and a preservative, and then mixed using a homogenezing mixer (PRIMIX) to first disperse the zinc oxide dispersion into the oil phase. Once the oil phase component and the powder were sufficiently mixed, the aqueous component (bulking agent, solvent) was slowly added to perform preliminary emulsification. Afterward, all of the aqueous component was added and main emulsification was performed; when the emulsification process was completed, the mixture was degassed to prepare the UV-blocking cosmetic composition according to Example 1 and Comparative Example 1.

[0113]

[0114] (3) Formulation stability evaluation

[0115] The formulation stability of a sunscreen cosmetic composition containing a zinc oxide dispersion prepared according to Example 1 and Comparative Example 1 was evaluated. The specific experimental method is as follows.

[0116] Specifically, the viscosity of the cosmetic composition on the day of manufacture and the viscosity after storage for one month at each temperature (5, 25, 45 ℃) were measured using a Brookfield viscometer (DV2TLBJO) with LV pin 4 at 6 rpm to evaluate whether the viscosity and formulation immediately after manufacture were maintained. Formulation stability was evaluated as 'excellent' if the change in viscosity over one month was less than 20%, 'average' if the change in viscosity was between 20% and 30%, and 'poor' if the change in viscosity exceeded 40% or the formulation separated. The measurement results are shown in Table 2 below.

[0117]

[0118] (4) Measurement of turbidity

[0119] The opacity of the UV-blocking cosmetic compositions prepared according to Example 1 and Comparative Example 1 was measured. The specific experimental method is as follows.

[0120] Each sample (Example 1 and Comparative Example 1) was applied to a polymethyl methacrylate (PMMA 'HELIO PLATE HD6') plate in an amount of 32 mg / cm² and rubbed with a finger for about 30 seconds. Then, the plate was placed on a piece of paper with writing on it, and the turbidity was measured based on the transparency of whether the writing was visible to the naked eye. Additionally, the results of the turbidity measurements for Example 1 and Comparative Example 1 were photographed and are shown in Fig. 1.

[0121]

[0122] (5) Evaluation of UV protection efficacy

[0123] The UV blocking efficacy of the UV blocking cosmetic compositions prepared according to Example 1 and Comparative Example 1 above was evaluated, and the results are shown in Table 2 below. The specific experimental method is as follows.

[0124] According to the test standard of the COLIPA (European Cosmetics Association) method for the in-vitro determination of UVA protection provided by sunscreen products, the sample was placed on a polymethyl methacrylate (PMMA HELIO PLATE HD6) plate at 32 mg / cm² 2 Each was applied, and the ultraviolet transmittance was measured using UV-2000S (Labsphere, Inc. USA), and the results are shown in FIGS. 2 and 3. The SPF value was calculated according to the following formula (1), and the average value of the calculation results was calculated and shown in Table 2 below.

[0125]

[0126] Here, S(λ) represents the erythematous effect spectrum, and S er (λ) represents the radiant intensity within the spectrum obtained from the UV source, and T(λ) represents the average monochromatic absorption of the test product film before UV irradiation.

[0127] UVAPF values ​​were calculated according to the following formula (2), and the average value of the calculation results was calculated and shown in Table 2 below.

[0128]

[0129] Here, E(λ) represents the standard ultraviolet spectrum, S(λ) represents the skin sensitivity function in UVA (320–400 nm), and T(λ) represents the transmittance when the test product is applied to the skin.

[0130]

[0131] (6) Skin adhesion evaluation

[0132] The skin adhesion of the UV-blocking cosmetic compositions prepared according to Example 1 and Comparative Example 1 above was evaluated by a skin panel test. Specifically, 30 mg of each sample was applied to the skin of 10 panel testers, and the skin adhesion was evaluated on a scale of 1 to 5, with lower scores assigned as the adhesion was lower. The average value of the scores evaluated by the 10 panel testers was calculated, and the results are shown in Table 2 below.

[0133]

[0134]

[0135] As shown in Table 2 above, the sunscreen cosmetic composition containing the zinc oxide dispersion of Example 1 was confirmed to have excellent formulation stability with the zinc oxide dispersion evenly dispersed, whereas the composition of Comparative Example 1 was confirmed to have poor formulation stability.

[0136] As shown in Table 2 and Figures 1 to 3 above, the cosmetic composition of Example 1 was confirmed to have low turbidity and excellent UV-B blocking performance, while the cosmetic composition of Comparative Example 1 was confirmed to have slightly improved UV-A blocking performance, but a sharp decrease in UV-B blocking rate and high turbidity.

[0137] It was confirmed that the cosmetic composition of Example 1 had improved adhesion and excellent usability. On the other hand, it was confirmed that the composition of Comparative Example 1 had poor adhesion and poor usability.

[0138]

[0139] Through the above experiment, it was confirmed that polyhydroxystearic acid affects zinc oxide dispersions and cosmetic compositions. Therefore, it was confirmed that dispersing zinc oxide using polyhydroxystearic acid is an important factor in the formulation formation, stability, UV protection efficacy, and usability of the UV-blocking cosmetic composition containing the zinc oxide dispersion of the present invention.

[0140]

[0141] Experimental Example 2. Comparative experiment according to the addition of the first emulsifier, the second emulsifier, and the dispersant

[0142] In the case of the UV-blocking cosmetic composition of Example 1, prepared by combining the first emulsifier, the second emulsifier, and the dispersant component with the zinc oxide dispersion of the present invention (Preparation Example 1), in order to investigate the effect of the first emulsifier, the second emulsifier, and the dispersant component on the formulation and efficacy of the cosmetic composition, UV-blocking cosmetic compositions of Comparative Examples 2 to 4 were prepared by excluding some of the first emulsifier, the second emulsifier, and the dispersant component, and then the efficacy of the formulation was evaluated. The specific manufacturing method is as follows.

[0143]

[0144] (1) Preparation of a cosmetic composition for ultraviolet protection

[0145] In addition to the components listed in Table 3 below, the compositions of Comparative Examples 2 to 4 were prepared using the same components and manufacturing method as performed in Example 1. Specifically, Comparative Examples 2 to 4 are compositions that do not include one of the first emulsifier, the second emulsifier, and the dispersant. In Table 3 below, the unit of the content of each component is weight%.

[0146]

[0147]

[0148] (2) Formulation stability evaluation

[0149] For the sunscreen cosmetic compositions prepared according to Comparative Examples 2 to 4 above, formulation stability was evaluated in the same manner as performed in Experimental Example 1. The evaluation results are summarized in Table 4 below.

[0150]

[0151] (3) Measurement of turbidity

[0152] The turbidity of the UV-blocking cosmetic compositions prepared according to Comparative Examples 2 to 4 above was measured in the same manner as performed in Experimental Example 1. The measurement results are shown in Table 4 and Figure 4 below.

[0153]

[0154] (4) Evaluation of UV protection efficacy

[0155] The UV blocking efficacy of the cosmetic compositions containing the zinc oxide dispersions prepared according to Comparative Examples 2 to 4 above was evaluated in the same manner as that performed in Experimental Example 1. The evaluation results are shown in Table 4 and Figures 5 to 7 below.

[0156]

[0157] (5) Skin adhesion evaluation

[0158] Skin adhesion evaluation was performed on the UV-blocking cosmetic compositions prepared according to Comparative Examples 2 to 4 above in the same manner as performed in Experimental Example 1. The evaluation results are summarized in Table 4 below.

[0159]

[0160]

[0161] As shown in Table 4 above, the compositions of Comparative Examples 2 to 4, which do not contain any one of the components of polyglyceryl-3 polydimethylsiloxyethyl dimethicone (first emulsifier), lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone (second emulsifier), and polyglyceryl-5 polyricinoleate (dispersant), were found to have separated formulations and reduced formulation stability.

[0162] As shown in Table 4 and Figures 4 to 7 above, it was confirmed that the compositions of Comparative Examples 2 to 4 showed increased opacity, reduced UV blocking efficacy, and reduced skin adhesion compared to the Examples.

[0163]

[0164] Through the above experiment, it was confirmed that the first emulsifier, the second emulsifier, and the dispersant components affect the zinc oxide dispersion and the cosmetic composition. Therefore, it was confirmed that including all three types of the first emulsifier, the second emulsifier, and the dispersant is an important factor in the formulation formation, stability, UV protection efficacy, and usability (cloudiness, adhesion) of the UV-blocking cosmetic composition containing the zinc oxide dispersion of the present invention.

[0165]

[0166] Experimental Example 3. Comparative experiment according to the content of the first emulsifier, second emulsifier, and dispersant

[0167] To investigate the effect of the content of the first emulsifier, the second emulsifier, and the dispersant on the zinc oxide dispersion, the addition amounts of the first emulsifier, the second emulsifier, and the dispersant were varied to prepare UV-blocking cosmetic compositions of the Examples and Comparative Examples, and the efficacy of the formulations was evaluated. The specific manufacturing method is as follows.

[0168]

[0169] (1) Preparation of a cosmetic composition for ultraviolet protection

[0170] To evaluate the efficacy of cosmetic compositions according to the contents of the first emulsifier, second emulsifier, and dispersant listed in Table 5 below, cosmetic compositions of Comparative Examples 5 to 7 were prepared by changing the content of the first emulsifier (polyglyceryl-3 polydimethylsiloxyethyl dimethicone) based on Example 1. Additionally, cosmetic compositions of Example 2, Comparative Example 8, and Comparative Example 9 of the composition according to the present invention were prepared by changing the content of the second emulsifier (lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone). Furthermore, cosmetic compositions of Example 3, Comparative Example 10, and Comparative Example 11 of the composition according to the present invention were prepared by changing the content of the dispersant (polyglyceryl-5 polyricinoleate). Here, the remaining components and their contents, excluding the first emulsifier, second emulsifier, and dispersant, are the same as in Example 1. In Table 5 below, the unit of the content of each component is weight%.

[0171]

[0172]

[0173] (2) Formulation stability evaluation

[0174] For the sunscreen cosmetic compositions prepared according to Examples 2 to 3 and Comparative Examples 5 to 11 above, formulation stability evaluation was conducted in the same manner as performed in Experimental Example 1. The evaluation results are summarized in Table 6 below.

[0175]

[0176] (3) Measurement of turbidity

[0177] The turbidity of the UV-blocking cosmetic compositions prepared according to Examples 2 to 3 and Comparative Examples 5 to 11 above was measured in the same manner as performed in Experimental Example 1. The measurement results are shown in Table 6 and Figures 8 to 11 below.

[0178]

[0179] (4) Evaluation of UV protection efficacy

[0180] The UV blocking efficacy of the cosmetic compositions containing zinc oxide dispersions prepared according to Examples 2 to 3 and Comparative Examples 5 to 11 above was evaluated in the same manner as performed in Experimental Example 1. The evaluation results are shown in Table 6 and Figures 12 to 20 below.

[0181]

[0182] (5) Skin adhesion evaluation

[0183] Skin adhesion evaluation was performed on the UV-blocking cosmetic compositions prepared according to Examples 2 to 3 and Comparative Examples 5 to 11 in the same manner as performed in Experimental Example 1. The evaluation results are summarized in Table 6 below.

[0184]

[0185]

[0186] As shown in Table 6 above, compared to the examples, Comparative Examples 5 and 6, which contain a small amount of polyglyceryl-3 polydimethylsiloxyethyl dimethicone (first emulsifier), were found to have separated formulations, resulting in low formulation stability and reduced UV blocking efficacy and adhesion. In addition, Comparative Example 7, which contains an excess amount of polyglyceryl-3 polydimethylsiloxyethyl dimethicone, was also found to have failed to form a formulation, and while it had excellent UV blocking efficacy and adhesion, it was found to have high turbidity.

[0187] It was confirmed that the cosmetic composition of Example 2, containing lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone (second emulsifier) ​​in appropriate weight and weight ratio, has a zinc oxide dispersion that is stably and evenly dispersed within the composition, has a suitable viscosity, and exhibits excellent formulation stability. On the other hand, the composition of Comparative Example 8, which contains a small amount of lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone compared to the example, did not exhibit a formulation. Comparative Example 9, which contains an excess amount of lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone compared to the example, was found to have excellent UV blocking efficacy and adhesion due to the excess amount of lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone, but the formulation separated and had high turbidity.

[0188] It was confirmed that the cosmetic composition of Example 3, containing polyglyceryl-5 polyricinoleate (dispersant) in an appropriate weight and weight ratio, has a zinc oxide dispersion that is stably and evenly dispersed within the composition, has a suitable viscosity, and exhibits excellent formulation stability. On the other hand, the composition of Comparative Example 10, which contains a small amount of polyglyceryl-5 polyricinoleate compared to the example, did not exhibit a formulation. Comparative Example 11, which contains an excess amount of polyglyceryl-5 polyricinoleate compared to the example, was found to have improved UV blocking efficacy and adhesion due to the excess inclusion of polyglyceryl-5 polyricinoleate, but exhibited low formulation stability and high turbidity.

[0189]

[0190] Through this, it can be seen that in order to simultaneously secure the formulation stability, UV blocking effect, and usability (low cloudiness, adhesion) desired in the present invention, it is necessary to appropriately maintain the weight and weight ratio of the first emulsifier, the second emulsifier, and the dispersant, respectively, when preparing a cosmetic composition containing a zinc oxide dispersion.

[0191]

[0192] Foregoing, specific parts of the content of the present invention have been described in detail. It will be apparent to those skilled in the art that such specific descriptions are merely preferred embodiments and do not limit the scope of the present invention. Accordingly, the actual scope of the present invention is defined by the appended claims and their equivalents.

Claims

In a cosmetic composition for sunscreen, Comprising a zinc oxide dispersion, a first emulsifier, a second emulsifier, and a dispersant, The above zinc oxide dispersion is a cosmetic composition for UV protection in which zinc oxide is dispersed using polyhydroxystearic acid. In Article 1, A cosmetic composition for UV protection, wherein the zinc oxide is included in an amount of 30 to 70 weight% based on the total weight of the zinc oxide dispersion. In Article 1, The above zinc oxide dispersion is a cosmetic composition for sunscreen comprising zinc oxide, propylheptyl caprylate, polyhydroxystearic acid, and triethoxycaprylylsilane. In Article 1, A cosmetic composition for UV protection, wherein the zinc oxide dispersion is included in an amount of 5 to 50 weight% based on the total weight of the cosmetic composition. In Article 1, A cosmetic composition for UV protection, wherein the first and second emulsifiers are different polyglyceryl-based emulsifiers. In Article 1, A cosmetic composition for UV protection, wherein the first emulsifier is included in an amount of 1.1 to 7 weight percent based on the total weight of the cosmetic composition. In Article 1, A cosmetic composition for UV protection, wherein the second emulsifier is included in an amount of 0.1 to 7 weight percent based on the total weight of the cosmetic composition. In Article 1, A cosmetic composition for UV protection, wherein the first emulsifier and the second emulsifier are included in a weight ratio of 1:0.14 to 0.

9. In Article 1, The above-mentioned dispersant is a cosmetic composition for UV protection comprising polyglyceryl-5 polyricinoleate. In Article 1, A cosmetic composition for UV protection, wherein the above-mentioned dispersant is included in an amount of 0.1 to 7 weight percent based on the total weight of the cosmetic composition. In Article 1, A cosmetic composition for UV protection, wherein the first emulsifier and the dispersant are included in a weight ratio of 1:0.14 to 0.

9. In Article 1, A cosmetic composition for UV protection, wherein the second emulsifier and the dispersant are included in a weight ratio of 1:0.2 to 7. In Article 1, A cosmetic composition for UV protection, wherein the first emulsifier, the second emulsifier, and the dispersant are included in a weight ratio of 1:0.14 to 0.9:0.14 to 0.9.

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