Solid ultraviolet-blocking cosmetic composition having water resistance and cleansing properties

Abstract

The present application provides a solid cosmetic composition containing an ultraviolet blocking agent, a fatty acid, and a wax, which is excellent in water resistance and / or cleansing property and can effectively block ultraviolet rays. More specifically, the ultraviolet blocking cosmetic composition of the present application is excellent in water resistance at low pH but is converted at high pH at the time of skin cleansing to make the cleansing property excellent, and thus can be usefully used.

Description

Technical Field

[0001] This application claims priority based on Korean Application No. 10-2020-0069819, filed on June 9, 2020, and Korean Application No. 10-2020-0101070, filed on August 12, 2020, and all contents disclosed in the descriptions and drawings of the relevant applications are incorporated herein by reference.

[0002] This invention relates to cosmetic compositions for blocking ultraviolet radiation. More specifically, it relates to cosmetic compositions for blocking ultraviolet radiation that exhibit excellent water resistance and cleanliness. Background Technology

[0003] Sunscreens that are easily wiped off by sweat or water are insufficient to adequately protect the skin from UV damage; therefore, water resistance is important for UV-blocking cosmetics. However, cleansing ability is also crucial. UV blockers left on the skin without being completely wiped off can cause a gritty feeling and potentially lead to problems. Therefore, the ideal UV-blocking cosmetic should possess the following characteristics: it is not easily wiped off by water and sweat, yet it has high cleansing power, making it easy to wipe off when desired.

[0004] In addition, stick-type UV-blocking cosmetics have recently been developed. The biggest advantage of stick sunscreens is that they can be applied without getting your hands dirty. Ordinary stick cosmetics are made using oil-based polymers or waxes. When waxes are used, lip wax or ceresin wax are commonly used.

[0005] On the other hand, fatty acids are difficult to impart with high hardness and high melting point, and therefore are not practically used in stick cosmetics. That is, to prepare conventional solid cosmetics, it is difficult to use substances with low melting points due to product stability and quality issues. For example, under high-temperature storage conditions, a portion of the product may melt, leading to changes in quality, and over the long term, there may be problems with decreased hardness and breakage during use. In this respect, fatty acids are not suitable raw materials for preparing solid cosmetics. Therefore, to prepare solid cosmetics, waxes with higher melting points have always been used, and even if they contain fatty acids, their content is formulated at a lower level compared to other waxes.

[0006] As mentioned earlier, water resistance and ease of cleansing are important factors for UV blockers, but it is difficult to satisfy both simultaneously. Furthermore, it is difficult to combine the ease of use inherent in solid formulations with both water resistance and ease of cleansing. The reality is that there is a need to develop UV blockers that satisfy all three of these characteristics. Summary of the Invention

[0007] Technical issues

[0008] Therefore, the problem to be solved by the present invention is to provide a cosmetic composition for blocking ultraviolet rays that has excellent water resistance and cleanliness.

[0009] Another problem to be solved by the present invention is to provide a solid UV-blocking cosmetic composition that is easy to use, water-resistant, and has excellent cleanability.

[0010] Technical solution

[0011] In order to achieve the above-mentioned technical problem, the inventors of the present invention disclosed that a solid ultraviolet blocking cosmetic containing specific ingredients, especially containing a high content of fatty acids, is stable and will not be wiped off by ordinary water or sweat with a low pH, but can be easily wiped off by soapy water with a high pH, ​​thus completing the present invention.

[0012] If a solid cosmetic composition for UV blocking containing fatty acids is prepared, it will possess water resistance due to its hydrophobic properties when applied to the skin. However, when exposed to water with a high pH, ​​such as soapy water, the fatty acids undergo a saponification reaction, exhibiting surfactant properties and effectively washing away oily components applied to the skin. To achieve this, the fatty acid content of the solid cosmetic composition is important.

[0013] One aspect of the present invention provides a cosmetic composition for blocking ultraviolet rays, characterized in that it comprises an ultraviolet antagonist, a fatty acid, an oil, and a wax, wherein the fatty acid is 5 to 40% by weight relative to the total weight of the composition and is in solid form.

[0014] For oil-in-water emulsions, because they contain emulsifiers, the UV-blocking film on the skin will be re-emulsified by the emulsifiers, thus having the disadvantage that they are inherently difficult to be water-resistant due to the characteristics of the formulation.

[0015] In addition, for water-in-oil emulsions, even if they are water-resistant, the structural characteristics of fatty acids will create a competitive relationship with the emulsifier at the interface, making it difficult to stabilize fatty acids and thus difficult to contain fatty acids at a high content.

[0016] On the other hand, solid dosage forms not only have water resistance and easy cleaning, but also good usability, and can have a variety of advantages as cosmetic compositions.

[0017] In this invention, the appropriate use of solid dosage form characteristics, fatty acid characteristics, and fatty acid content helps to achieve the objectives of this invention.

[0018] In a preferred aspect of the invention, the composition of the invention is substantially free of water.

[0019] In this invention, the term "substantially not containing" can be understood to mean that, relative to the total weight of the composition, the content is less than 5% by weight, preferably less than 3% by weight, preferably less than 1% by weight, more preferably less than 0.5% by weight, more preferably less than 0.1% by weight, and even more preferably less than 0.01% by weight, and cases where it is completely not contained (0% by weight) can also be included in the scope of "substantially not containing" in this invention.

[0020] Therefore, preferably, the composition disclosed herein does not contain water, or the content of water may be less than 5% by weight, more preferably less than 3% by weight, or even more preferably less than 1% by weight relative to the total weight of the composition.

[0021] The cosmetic composition of the present invention is not dispersible in water at pH 7, but can be dispersed in aqueous solutions at pH 9 to 14.

[0022] In this invention, the term "dispersion" refers to the uniform distribution of another substance in a substance (dispersion medium) without depositing in the lower layer of the dispersion medium or floating in the upper layer. In particular, in this specification, dispersion can refer to a phase in which no separation is observed after dispersion.

[0023] The cosmetic composition of the present invention is a solid ultraviolet blocking cosmetic composition with improved water resistance and cleansing properties.

[0024] In one aspect of the invention, the content of the wax is 5 to 40% by weight, preferably 6 to 30% by weight, and more preferably 12 to 25% by weight, relative to the total weight of the composition.

[0025] The waxes mentioned above are included for the preparation of solid dosage forms. When the content of the waxes is too low, it is difficult to ensure the stability of the composition; when the content of the waxes is too high, the composition may be too hard, resulting in a poor user experience or reduced effectiveness of the invention.

[0026] In this invention, the waxes mentioned above can be plant-based waxes such as candelilla wax, carnauba wax, or rice wax; animal-based waxes such as beeswax or lanolin; mineral-based waxes such as ozokerite or pure ozokerite; petroleum-based waxes such as paraffin wax or microcrystalline wax; synthetic waxes such as polyethylene wax, polypropylene wax, or ethylene / propylene copolymer, etc., but are not limited to these.

[0027] In this invention, for example, a polyethylene wax with a melting point of 50 to 120°C, preferably 60 to 110°C, and more preferably 70 to 100°C can be used as the aforementioned polyethylene wax. In this invention, for example, PERFORMALENE 400, a product of NewPhase Technologies, can be used as the aforementioned polyethylene wax. TM .

[0028] In this invention, the synthetic wax described above can be, for example, the trade name LIPWAX PZ80-20 from JAPAN NATURAL PRODUCTS. TM .

[0029] In this invention, the ultraviolet blocking agent can be an inorganic ultraviolet blocking agent and / or an organic ultraviolet blocking agent.

[0030] In this invention, titanium dioxide, zinc oxide, etc., can be used as the aforementioned inorganic ultraviolet blocking agent, but are not limited thereto. However, zinc oxide hinders the saponification reaction of fatty acids by releasing divalent zinc ions, thereby negatively impacting cleanliness, and is therefore less preferred.

[0031] In this invention, the following substances can be used alone or in combination as the above-mentioned organic ultraviolet blocking agents: ethylhexyl methoxycinnamate, ethylhexyl salicylate, diethylhexyloxyphenol methoxyphenyl triazine, diethylaminohydroxybenzoyl benzoate, octocrylene, butyl methoxydibenzoylmethane, hydroxybenzophenone, octyl triazine, menthyl anthranilate, phenylbenzimidazole sulfonic acid, 2-hydroxy-4-methoxydibenzophenone sulfonic acid, 3,4-methylbenzyl camphor, isoamyl p-methoxycinnamate, humosalilate, cresoltrazolium trisiloxane, benzophenone-3, ethylhexyl triazine, DEA salt of methoxycinnamate, disodium phenyl dibenzimidazole tetrasulfonate, benzophenone-8, TEA salt of salicylate, butyl methoxydibenzoylmethane, ethylhexyl dimethyl PABA, etc., but are not limited thereto.

[0032] Preferably, the following substances can be used alone or in combination as the above-mentioned organic ultraviolet blocking agents: ethylhexyl methoxycinnamate, octocrylene, ethylhexyl salicylate, diethylhexyloxyphenol methoxyphenyl triazine, diethylaminohydroxybenzoyl hexyl benzoate, etc.

[0033] In this invention, the content of the above-mentioned ultraviolet blocking agent may be 10 to 40% by weight, preferably 15 to 35% by weight, and more preferably 18 to 30% by weight, relative to the total weight of the composition.

[0034] The solid cosmetic composition of the present invention contains fatty acids in a high content. Preferably, the fatty acid content is 5% by weight or more, more preferably 10% by weight or more, relative to the total weight of the composition. When the fatty acid content is less than 5% by weight, the effect of the present invention may be reduced. That is, the solid cosmetic composition of the present invention contains 5 to 40% by weight, more preferably 10 to 30% by weight, of fatty acids relative to the total weight of the composition.

[0035] In a preferred aspect of the invention, the content of the fatty acid in the composition of the invention is greater than 1 to less than 5 times the weight of the wax.

[0036] When determining the content of the fatty acids mentioned above, it is best to also consider the content of wax. Because wax components can form a hard film, the ease of cleaning may be poor. In this case, adjusting the content of fatty acids to be higher than the content of wax may help improve the effectiveness of the invention.

[0037] In this invention, the aforementioned fatty acids can be in a solid or liquid state at room temperature, preferably in a liquid state. When the aforementioned fatty acids are in a liquid state at room temperature, they have the effect of improving the hardness of the dosage form and have little impact on stability, thus allowing for the incorporation of fatty acids at high concentrations. However, the effects of this invention (UV blocking effect, water resistance, and cleaning power) are excellent when using liquid fatty acids, solid fatty acids, or mixtures thereof.

[0038] In this invention, the fatty acids that are solid at room temperature can be used broadly to include those in a semi-solid state.

[0039] In one aspect of the present invention, when the composition of the present invention simultaneously comprises solid fatty acids and liquid fatty acids, the content of liquid fatty acids in the composition of the present invention is greater than 1 to less than 100 times the weight of solid fatty acids, preferably greater than 1 to less than 50 times the weight, more preferably greater than 1 to less than 20 times the weight, and even more preferably greater than 1 to less than 8 times the weight.

[0040] When the content of liquid fatty acids is higher than that of solid fatty acids, it has several advantages, such as improved sweating phenomenon in the dosage form.

[0041] In this invention, the fatty acid can be a saturated fatty acid or an unsaturated fatty acid with 12 to 22 carbon atoms.

[0042] Preferably, in this invention, the fatty acid can be stearic acid, palmitic acid, myristic acid, isostearic acid, behenic acid, or a mixture thereof. More preferably, the fatty acid is isostearic acid. In particular, when the fatty acid is isostearic acid, it has less impact on stability and excellent performance, thus being preferred, and also has many advantages such as improved user experience.

[0043] In this invention, preferably, the degree of neutralization of the fatty acids can be 5 or less, more preferably 1 or less, and most preferably 0 (unneutralized fatty acids).

[0044] In this invention, the oil contained in the cosmetic composition of this invention can be a conventional oil used in cosmetic compositions. For example, silicone oil, natural oil, ester oil, hydrocarbon oil, etc., can be used as the oil, but it is not limited thereto.

[0045] In this invention, both non-volatile and volatile silicone oils can be used as the aforementioned silicone oil. As the aforementioned non-volatile silicone oil, amodimethicone, bisphenylhexamethicone, dimethicone, hexadecylmethicone, methicone, phenyltrimethicone, simethicone, dimethylhydrosiloxane, stearoxytrimethylsiloxane, vinyl dimethicone, etc., can be used, but are not limited to these. As the aforementioned volatile silicone oil, octamethylcyclotetrasiloxane, decamethylcyclopentane, dodecylcyclohexylsiloxane, hexamethyldisiloxane, cyclomethicone, etc., can be used, but are not limited to these.

[0046] In this invention, the aforementioned natural oil can be oil obtained from plants that exist in nature. For example, sunflower seed oil, avocado oil, orange oil, macadamia seed oil, lemon oil, pine nut oil, jojoba seed oil, olive oil, green tea seed oil, coconut oil, rosehip oil, Damask rose oil, Brazil nut seed oil, moringa seed oil, grapefruit seed oil, soybean oil, vanilla seed oil, etc., but not limited to these, can be used as natural oils.

[0047] In this invention, the aforementioned ester oil can be an ester compound of fatty acids and fatty alcohols. For example, as the aforementioned ester oil, dimeric pentaerythritol hexa-C can be used. 5-9 Acid esters, C 12-15 Alkyl octanoate, myristyl lactate, cetyl ethylhexanoate, cetyl octanoate, isopropyl myristate, octyl dodecyl myristate, hexyl laurate, di(C 12-13Examples of such products include, but are not limited to, alkanol malate, myristyl lactate, octyl dodecyl stearyl oxystearate, diisostearyl malate, pentaerythrityl tetraethylhexanoate triethylhexanoin, and diglyceryl triisostearate.

[0048] In this invention, the aforementioned hydrocarbon oils can be petroleum-based oils such as flowing paraffin, petrolatum, and isoparaffins; synthetic oils such as hydrogenated polydecene, synthetic squalane, and polybutene; and plant-based oils such as vegetable squalane and hydrogenated squalane, but are not limited thereto. Specifically, oils such as isohexadecane, isodecane, undecane, squalane (vegetable squalane), synthetic squalane, hydrogenated polydecene α-olefin oligomer, and hydrogenated polyisobutylene can be used, but are not limited thereto.

[0049] Preferably, the oil can be hexyl laurate, triisooctanoic acid glyceride, or a mixture thereof.

[0050] In this invention, the content of the oil relative to the total weight of the composition can be 5 to 55% by weight, preferably 10 to 50% by weight, more preferably 15 to 40% by weight, and even more preferably 25 to 40% by weight.

[0051] In one aspect of the invention, it is preferred that the cosmetic composition of the invention does not substantially contain a neutralizing agent.

[0052] In this invention, the cosmetic composition may further comprise all kinds of additives that can be used in conventional cosmetics, such as preservatives, fragrances, pigments, powders, thickeners, opacifiers, binders, viscosity modifiers, colorants, scenting agents, film-forming agents, etc. These additives are commercially available and readily used.

[0053] In this invention, the solid cosmetic composition may contain powder to improve the user experience. As the powder, silica, talc, PMMA (polymethylmethacrylate) powder, polymethylsilsesquioxane, etc., may be used, but are not limited thereto. Preferably, the powder is polymethylsilsesquioxane.

[0054] In another aspect of the invention, a cosmetic composition for blocking ultraviolet radiation is provided, characterized in that, relative to the total weight of the composition, the composition of the present invention comprises: 10 to 40% by weight (preferably 15 to 35% by weight, more preferably 18 to 30% by weight) of an ultraviolet blocking agent, wherein the ultraviolet blocking agent is ethylhexyl methoxycinnamate, octocrylene, ethylhexyl salicylate, bis(ethylhexyloxyphenol)methoxyphenyltriazine, ethylaminohydroxybenzoyl benzoate, or a mixture thereof; and 5 to 40% by weight (preferably 10 to 30% by weight) of... The composition comprises: fatty acids, including myristic acid, palmitic acid, stearic acid, isostearic acid, behenic acid, or mixtures thereof; 5 to 40% by weight (preferably 6 to 30% by weight, more preferably 12 to 25% by weight) of wax, including polyethylene, ethylene / propylene copolymer, synthetic wax, or mixtures thereof; and 5 to 55% by weight (preferably 10 to 50% by weight, more preferably 15 to 40% by weight, even more preferably 25 to 40% by weight) of oil, including triisooctanoic acid glyceryl ester, hexyl laurate, or mixtures thereof, and is solid. The composition is not dispersed at pH 7 but is dispersed in an aqueous solution at pH 9 to 14.

[0055] In this invention, the composition may further comprise 5 to 30% by weight (preferably 7 to 25% by weight, more preferably 9 to 22% by weight) of polymethylsilsesquioxane relative to the total weight of the composition.

[0056] Preferably, all ingredients described in this invention do not exceed the maximum usage limits specified in relevant regulations and standards in Korea, China, Europe, Japan, etc. (e.g., cosmetic safety standards and related regulations (Korea), cosmetic safety technical specifications (China), hygiene standards (China)). That is, preferably, the cosmetic composition of this invention contains the ingredients of this invention within the content limits permitted by the relevant regulations and standards of each country.

[0057] Invention Effects

[0058] This invention provides a solid cosmetic composition that exhibits excellent water resistance and cleansing properties while effectively blocking ultraviolet rays. More specifically, the cosmetic composition of this invention provides a composition that exhibits excellent water resistance at low pH levels, but transforms into an ultraviolet-blocking composition that provides excellent cleansing properties at high pH levels during skin cleansing. Attached Figure Description

[0059] Figure 1 The dispersion test results of Comparative Example 1 and Example 14 are shown.

[0060] Figure 2 The dispersion test results of Comparative Example 1 and Examples 1 to 10 are shown.

[0061] Figure 3 The figure shows the shear hardness measurement results of Examples 11 to 15.

[0062] Figure 4 The graph shows the melting point measurement results of Examples 11 to 15. Detailed Implementation

[0063] In the following detailed description, exemplary embodiments will be provided to aid in understanding the invention. However, the embodiments of the invention can be modified in various different forms, and the scope of the invention should not be construed as limited to the following embodiments. The embodiments of the invention are provided to illustrate the invention more completely to those skilled in the art.

[0064] Example 1. Preparation based on comparative examples and examples of fatty acid content

[0065] A stick-type sunscreen was prepared using the formula shown in Table 1. Following the formula in Table 1, all ingredients were mixed, heated to 90°C, and stirred until completely dissolved. The mixture was then poured into a stick container and cooled to room temperature.

[0066] [Table 1]

[0067]

[0068] In Table 1 above, the polyethylene wax used is PERFORMALENE 400 from New Phase Technologies. TM The synthetic wax and ethylene / propylene copolymer use a specific wax and ethylene / propylene copolymer contained in a weight ratio of 8:2 under the trade name Lipwax PZ80-20 from JAPAN NATURAL PRODUCTS. TM As a polymethylsilsesquioxane, N&M TECH's SESQ-101 was used. TM The same raw materials were also used in the other embodiments below.

[0069] Example 2. Preparation of an example based on fatty acid types

[0070] A stick-type sunscreen was prepared using the formula shown in Table 2. Following the formula in Table 2, all ingredients were mixed, heated to 90°C, and stirred until completely dissolved. The mixture was then poured into a stick container and cooled to room temperature.

[0071] [Table 2]

[0072] (Unit: % by weight) Example 11 Example 12 Example 13 Example 14 Example 15 Myristic acid 15 Palmitic acid 15 stearic acid 15 Isostearic acid 15 behenic acid 15 Hexyl lauryl ester 27 27 27 27 27 Polyethylene wax 15 15 15 15 15 Synthetic wax 2.4 2.4 2.4 2.4 2.4 Ethylene / propylene copolymer 0.6 0.6 0.6 0.6 0.6 Diethylhexyloxyphenol methoxyphenyl triazine 2 2 2 2 2 Diethylaminohydroxybenzoyl benzoate 2 2 2 2 2 Triisooctanoic acid glyceride 8 8 8 8 8 Ethylhexyl methoxycinnamate 7 7 7 7 7 Ethylhexyl salicylate 4 4 4 4 4 Octylene 7 7 7 7 7 Polymethylsilsesquioxane 10 10 10 10 10 total 100 100 100 100 100

[0073] Example 3. Preparation of the example based on fatty acid content (including cases where both solid and liquid fatty acids are used simultaneously).

[0074] A stick-type sunscreen was prepared using the formula shown in Table 3. Following the formula in Table 3, all ingredients were mixed, heated to 90°C, and stirred until completely dissolved. The mixture was then poured into a stick container and cooled to room temperature.

[0075] [Table 3]

[0076]

[0077] Experimental Example 1. Evaluation of Dispersion Force (Dispersion Experiment)

[0078] The dispersion experiment was conducted by dispersing solid sunscreen sticks in ordinary purified water (pH 7) and tromethamine aqueous solution (pH 10) and observing the degree of dispersion. Figure 1 , Figure 2 (and Table 4).

[0079] As a result, it was confirmed that in Comparative Example 1, aqueous solutions at pH 7 and 10 were not dispersed, but in the Examples, they were dispersed. Compared to waxes, the dispersion was particularly excellent at higher fatty acid contents.

[0080] [Table 4]

[0081] pH 7 pH 10 Comparative Example 1 X X Example 1 X △ Example 2 X ○ Example 3 X ○ Example 4 X ○ Example 5 X ○ Example 6 X ◎ Example 7 X ◎ Example 8 X ◎ Example 9 X ◎ Example 10 X ◎ Example 11 X ◎ Example 12 X ◎ Example 13 X ◎ Example 14 X ◎ Example 15 X ◎ Example 16 X ◎ Example 17 X ◎ Example 18 X ◎ Example 19 X ◎ Example 20 X ◎ Example 21 X ◎ Example 22 X ◎

[0082] X: Completely undispersed, observed as transparent water.

[0083] △: It's a bit scattered, and the water has become a bit cloudy.

[0084] ○: Dispersed, the water becomes turbid.

[0085] ◎: Dispersion causes the water to become cloudy and a foam layer to form.

[0086] Experimental Example 2. Water Resistance Evaluation

[0087] The sunscreen sticks prepared using the formulations in Table 1 above were subjected to water resistance tests. The water resistance of the sunscreen sticks was tested at 1.3 mg / cm³. 2A thick layer was applied to a PMMA plate and then dried for at least 15 minutes. The transmittance of the dried PMMA plate was measured using a spectrophotometer. For transmittance, measurements were taken every 1 nm at three different locations on the PMMA plate in the 290–400 nm wavelength range. For water resistance evaluation, a round stainless steel container was appropriately filled with tap water, and the PMMA plate was fixed in place to ensure complete immersion in the water. The container was stirred at 3000 rpm using a disperser while standing for 30 minutes, then the PMMA plate was removed and dried for at least 30 minutes. The transmittance in the 290–400 nm wavelength range was measured again using a spectrophotometer on the completely dried PMMA plate. The transmittance measured before and after immersion was converted to in-vitro SPF values ​​using the following formula and compared. The water resistance ratio was calculated by dividing the SPF after immersion by the SPF before immersion. The results are summarized in Table 5 below.

[0088]

[0089] E λ Erythemal action spectrum

[0090] S λ Spectral irradiance (W / m²) 2 / nm)

[0091] T λ Transmittance

[0092] The results confirmed that the sunscreen sticks containing fatty acids in Examples 1-10 actually exhibited superior water resistance compared to the sunscreen stick without fatty acids (Comparative Example 1). This is because fatty acids do not react with water at a neutral pH and are hydrophobic, thus not affecting the water resistance of the sunscreen stick. Instead, they react with trace amounts of divalent ions in the water to form insoluble precipitates, thereby improving water resistance. Furthermore, due to the scattering effect of the insoluble precipitates, the SPF is further increased after immersion in water.

[0093] [Table 5]

[0094] SPF before soaking in water SPF after immersion in water Water resistance ratio (%) Comparative Example 1 89.45±10.04 19.7±7 22.02 Example 1 77.05±13.46 53.75±34.31 69.76 Example 2 101.75±30.53 55.57±48.63 54.61 Example 3 120.05±27.96 92.21±93.4 76.81 Example 4 112.82±13.78 91.25±32.49 80.88 Example 5 94.98±30.74 106.92±104.7 112.57 Example 6 154.1±56.96 291.57±165.83 189.21 Example 7 47.97±8.01 17.79±2.52 37.09 Example 8 67.58±15.91 26.54±5.86 39.27 Example 9 28.08±2.9 37.63±2.28 134.01 Example 10 35.00±2.29 101.58±69.5 290.23

[0095] Experimental Example 3. Cleaning Power Evaluation

[0096] The cleansing power of the sunscreen sticks prepared using the formulations in Table 1 was evaluated. Each sunscreen stick was tested at 1.3 mg / cm³. 2A thick layer of UV-transmitting agent was applied to a PMMA plate, and the transmittance in the 290–400 nm region was measured using a spectrophotometer. Transmittance measurements were taken at three different locations on the PMMA plate. Next, 0.2 g of a 20% dispersion of cleansing foam was placed on the PMMA plate, and the plate was cleansed evenly for 20 seconds using an electric facial cleansing device. After rinsing thoroughly with warm water and allowing to dry completely for at least 30 minutes, the transmittance was measured again using a spectrophotometer. The cleanliness rate was calculated using the following formula. The value that transmits more UV light than the control plate was replaced with the control plate value, and the cleanliness rate was assumed to be 100%. The results are shown in Table 6 below.

[0097]

[0098] Transmittance of the control PMMA plate at a single wavelength

[0099] Pre-cleaning transmittance at a single wavelength

[0100] Transmittance after cleaning at a single wavelength

[0101] Examples 1-10 showed a higher cleaning efficiency than Comparative Example 1. This is because fatty acids undergo saponification when they encounter soapy water with a high pH, ​​exhibiting amphoteric properties. Fatty acids not only function as surfactants but also detach from the sunscreen film through saponification, thus aiding in better removal of the oil film.

[0102] [Table 6]

[0103] Cleanliness rate (%) Improvement rate (%) relative to Comparative Example 1 Comparative Example 1 64.56 - Example 1 70.50 9.20 Example 2 71.76 11.15 Example 3 80.08 24.04 Example 4 78.24 21.19 Example 5 83.62 29.52 Example 6 79.81 23.62 Example 7 89.34 38.38 Example 8 85.88 33.02 Example 9 83.41 29.20 Example 10 81.21 25.79

[0104] Experimental Example 4. Hardness, melting point, and long-term stability at high temperatures.

[0105] When solid fatty acids are incorporated in high concentrations with waxes, stability may be affected, such as a decrease in hardness and melting point. Therefore, caution is required when using high concentrations of fatty acids in solid-state formulations. This is presumably because the solid fatty acids collectively participate in crystal formation, thus influencing the crystal structure; however, this invention is not limited to this theoretical mechanism.

[0106] Experimental Example 4-1. Shear Hardness Measurement

[0107] Shear hardness was measured, and the results are shown below. Figure 3In order to measure shear hardness, each sample was prepared into a cylindrical shape with a circular shape and a diameter of approximately 2.5 cm. The hardness was measured using an applicator #30 equipped with a piano wire at a depth of 1.5 cm and a speed of 2 cm / min.

[0108] As a result, Example 14, which uses isostearic acid, which is liquid at room temperature, exhibited the highest hardness. This is presumably because solid fatty acids affect the crystal structure of the wax, while liquid fatty acids do not; however, the invention is not limited to this theoretical mechanism.

[0109] Experimental Example 4-2. Melting Point Measurement

[0110] The melting point was observed using DSC based on the type of fatty acid. DSC was observed while the temperature was increased by 10°C per minute from 30°C to 95°C. The melting point measurement results are shown below. Figure 4 middle.

[0111] The results showed that when solid fatty acids were used, the melting point of the solid formulation decreased due to the inherent melting point of the fatty acids. However, no decrease in melting point was observed when liquid fatty acids were used. This is presumably because solid fatty acids participate in crystal formation and thus affect the crystal structure, while liquid fatty acids do not participate in crystal formation and therefore have no effect on the crystal structure; however, this invention is not limited to this theoretical mechanism.

[0112] Experimental Example 4-3. Long-term stability test at high temperature

[0113] Stability tests were conducted using the prepared sunscreen sticks. The experimental results are shown in Tables 7 and 8 below.

[0114] As a result, Examples 11-12, which have low melting points, failed to maintain their original hardness at high temperatures, and their hardness decreased under long-term high-temperature conditions for more than one month.

[0115] Sweatiness is an important stability factor in solid oil-wax gel formulations. Sweatiness occurs when high concentrations of solid fatty acids are used, but is not observed when liquid fatty acids are used.

[0116] [Table 7]

[0117] Types of fatty acids 40℃ stability 45℃ stability 50℃ stability sweating stability Example 11 Myristic acid △ X X X Example 12 Palmitic acid △ △ X X Example 13 stearic acid O O O X Example 14 Isostearic acid O O O O Example 15 behenic acid O O O △

[0118] (In Table 7 above, O means excellent stability, △ means moderate stability, and X means decreased stability.)

[0119] When solid and liquid fatty acids are used together, as in Examples 16-19, sweating occurs when the content of liquid fatty acids is lower than that of solid fatty acids. As in Examples 20-22, when the content of liquid fatty acids is higher, the sweating phenomenon is improved. Furthermore, as in Comparative Examples 2-3, even when solid fatty acids are included, the stick sunscreen is too soft if it does not contain wax or has a low wax content, making it unsuitable as a solid cosmetic due to poor high-temperature stability.

[0120] [Table 8]

[0121]

[0122] (In Table 8 above, O means excellent stability, △ means moderate stability, and X means decreased stability.)

[0123] Experimental Example 5. Evaluation of Water Resistance and Cleaning Power

[0124] Stick-type sunscreens were prepared and evaluated using the methods described above, according to the contents shown in Table 2 above. Their water resistance and cleansing properties are shown in Table 9 below. The results showed high water resistance and cleansing efficiency for all types of fatty acids.

[0125] [Table 9]

[0126] SPF before soaking in water SPF after immersion in water Water resistance ratio (%) Cleanliness rate (%) Example 11 127.47±32.16 305.68±55.43 239.80 80.09 Example 12 92.21±18.89 112.94±35.63 122.48 77.75 Example 13 58.91±13.64 163.91±9.98 278.23 82.04 Example 14 127.41±23.59 85.04±20.72 66.74 82.8 Example 15 69.08±4.54 61.06±43.79 88.39 80.65

Claims

1. A cosmetic composition for blocking ultraviolet rays, characterized in that, It contains UV blockers, fatty acids, oils, and waxes. The aforementioned UV blocker is 10 to 40% by weight relative to the total weight of the composition. The fatty acid mentioned above is isostearic acid, which accounts for 15 to 40% by weight relative to the total weight of the composition. The oil mentioned above is 5 to 55% by weight relative to the total weight of the composition. The wax described above is 5 to 40% by weight relative to the total weight of the composition. Furthermore, the aforementioned cosmetic composition for blocking ultraviolet rays is solid.

2. The cosmetic composition of claim 1, wherein, The above composition does not contain water.

3. The cosmetic composition of claim 1, wherein, The above cosmetic composition is not dispersed in water at pH 7, but is dispersed in aqueous solutions at pH 9 to 14.

4. The cosmetic composition of claim 1, wherein, The content of the aforementioned fatty acids is greater than 1 to less than 5 times the weight of the aforementioned wax.

5. The cosmetic composition of claim 1, wherein, The fatty acids mentioned above are in liquid form.

6. A cosmetic composition for blocking ultraviolet rays, characterized in that, Relative to the total weight of the composition, it comprises: 10 to 40% by weight of a UV blocker, wherein the UV blocker is ethylhexyl methoxycinnamate, octocrylene, ethylhexyl salicylate, diethylhexyloxyphenol methoxyphenyl triazine, diethylaminohydroxybenzoyl hexyl benzoate or a mixture thereof. 15 to 40% by weight of fatty acid, which is isostearic acid; 5 to 40% by weight of a wax, wherein the wax is polyethylene, ethylene / propylene copolymer, synthetic wax or a mixture thereof; and 5 to 55% by weight of oil, wherein the oil is triisooctanoic acid glyceride, hexyl laurate, or a mixture thereof. Furthermore, the above-mentioned UV-blocking cosmetic composition is solid, and the composition is not dispersed in water at pH 7, but dispersed in aqueous solutions at pH 9 to 14.

7. The cosmetic composition of claim 6, further comprising 5 to 30% by weight of polymethylsilsesquioxane relative to the total weight of the composition.

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