Sunscreen composition

Abstract

The sunscreen composition contains 2-51 mass% of a component (A), 9-80 mass% of a component (B), 0.1-14 mass% of a component (C), 0.1-10 mass% of a component (D), 5-40 mass% of a component (E), and 6-57 mass% of a component (F). The mass ratio ((A) / (B)) of the component (A) and the component (B) is 5 / 95-60 / 40.　Component (A): isoparaffin having an average carbon number of 50-250. Component (B): isoparaffin having an average carbon number of 20-24. Component (C): an emulsifier such as a sorbitan fatty acid ester having an HLB of 2-10. Component (D): a polyhydric alcohol that has 2-6 carbon atoms and is dihydric or trihydric. Component (E): an ultraviolet scattering agent. Component (F): water.

Description

Sunscreen composition

[0001] The present invention relates to sunscreen compositions.

[0002] In addition to their function of protecting skin from UV damage, there is also growing demand for sunscreen compositions that provide a good feel when used, and they are required to have a thick texture when spread, a thickness that gives the feeling of skin protection, and ease of spreading. For example, Patent Document 1 describes that by blending a specific dextrin fatty acid ester and a non-volatile phenyl-modified silicone into a makeup cosmetic having UV protection properties, the cosmetic can be applied thickly and adheres to the skin. Furthermore, Patent Document 2 describes a sunscreen cosmetic that has a good spreadability and a good feel when applied by blending a specific fatty acid alkanolamide derivative.

[0003] On the other hand, in recent years, as it has become more widely recognized that ultraviolet rays have a negative effect on the skin, sunscreen cosmetics are frequently used even in winter, when the amount of ultraviolet rays is low. When such sunscreen cosmetics are applied to the skin, the UV scattering agents and other film-forming substances contained therein cause a sensation of skin tension, i.e., a tight feeling. Furthermore, in dry air such as winter, the skin becomes dry, making the tight feeling even more likely to be felt. That is, in addition to the above-mentioned issues of thickness and ease of spreading when applied at low temperatures, sunscreen cosmetics also have the issue of a tight feeling.

[0004] The makeup cosmetic described in Patent Document 1 is good in terms of thickness, but sunscreen cosmetics prepared using it may be poor in spreadability and firmness at low temperatures. The cosmetic described in Patent Document 2 is good in spreadability upon application, but may be poor in thickness and firmness. That is, these cosmetics not only lack the effect of being easy to spread while maintaining a thickness upon application at low temperatures such as in winter, but also may be poor in firmness.

[0005] In order to solve the problem of the tightness feeling, Patent Document 3 discloses a sunscreen cosmetic containing a specific fine particle metal oxide, an aqueous phase thickener, and an amphoteric surfactant, and describes that this sunscreen cosmetic does not cause a tightness feeling and has an excellent feel when used.

[0006] JP 2017-114832 A JP 2018-52864 A JP 2021-138621 A

[0007] However, in winter sports such as skiing and snowboarding, which are carried out in winter, the skin is exposed to not only dryness but also wind, so although a sunscreen cosmetic does not feel tight immediately after application, its effectiveness may be lost over time. This is because ingredients such as moisturizing ingredients are more likely to volatilize in such environments, causing dryness and stiffness on the skin. Since the sunscreen cosmetic of Patent Document 3 may lose its effectiveness over time, there has been a demand for a sunscreen cosmetic that does not feel tight even after activities in dry or windy environments, and that also has an excellent usability in terms of thickness and ease of spreadability.

[0008] In view of the above problems, the present invention aims to provide a sunscreen composition that is easy to spread while maintaining a thick feel when applied even in a low-temperature environment, and that is less likely to cause a tight feeling over time even under dry or windy conditions, and that has an excellent feel when used.

[0009] As a result of extensive research to solve the above problems, the present inventors have found that by combining two specific types of isoparaffin, an emulsifier, and a specific polyhydric alcohol, a sunscreen composition can be obtained that can solve the above problems of thickness and ease of spreadability in a composition containing an ultraviolet scattering agent, as well as the problem of tightness over time under dry or windy conditions, and have thereby completed the present invention.

[0010] That is, the present invention provides a sunscreen composition containing 2 to 51 mass% of component (A), 9 to 80 mass% of component (B), 0.1 to 14 mass% of component (C), 0.1 to 10 mass% of component (D), 5 to 40 mass% of component (E), and 6 to 57 mass% of component (F), in which the mass ratio of component (A) to component (B) ((A) / (B)) is 5 / 95 to 60 / 40. Component (A): Isoparaffin having an average carbon number of 50 to 250 Component (B): Isoparaffin having an average carbon number of 20 to 24 Component (C): One or more emulsifiers selected from the group consisting of sorbitan fatty acid esters having an HLB of 2 to 10, fatty acid glyceryls having an HLB of 2 to 10, and polyoxyethylene mono-fatty acid glyceryls having an HLB of 2 to 10 Component (D): Polyhydric alcohols having 2 to 6 carbon atoms and 2 to 3 valences Component (E): UV scattering agent Component (F): Water

[0011] The sunscreen composition of the present invention has the effect of being easily spreadable while maintaining a thick feel at the time of application even in a low-temperature environment, and has the effect of making it difficult to feel a tight feeling over time even under dry or windy conditions.

[0012] Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the embodiments described herein and can be modified in various ways without departing from the spirit and scope of the present invention. In this specification, numerical ranges defined using the symbol "to" are intended to include both the upper and lower limits of the symbol "to." For example, "2 to 5" means 2 or more and 5 or less. Furthermore, in the numerical ranges described herein, the upper or lower limit of the numerical range can be replaced with the upper or lower limit of another numerical range, a value shown in an example, or a value uniquely derived from an example. Numerical values ​​described herein are subject to the inherent variability of the measurement technique used to determine the numerical value. Numerical values ​​should be interpreted in light of the number of significant digits and by applying the rounding method.

[0013] <Sunscreen Composition> The sunscreen composition of the present invention contains component (A), component (B), component (C), component (D), component (E), and component (F). Each component will be described below.

[0014] [Component (A)] Component (A) used in the present invention is an isoparaffin having an average carbon number of 50 to 250. This isoparaffin is a mixture of long-chain hydrocarbons having side chains, and is usually obtained by hydrogenating a polymer of isobutene and n-butene. Examples of such components include those generally classified as "heavy liquid isoparaffins" in the cosmetics field.

[0015] The lower limit of the average carbon number of isoparaffin is 50, preferably 60, more preferably 70, and particularly preferably 80. The upper limit of the average carbon number of isoparaffin is 250, preferably 230, more preferably 210, and particularly preferably 190. If the average carbon number is too small, it may be difficult to feel the thickness of the sunscreen composition when applied in a low-temperature environment, and a tight feeling may be felt over time. On the other hand, if the average carbon number is too large, the ease of spreading in a low-temperature environment may decrease. The range of the average carbon number of isoparaffin can be specified using numerical values ​​arbitrarily selected from the numerical values ​​described above as the upper and lower limits. Examples of the average carbon number of isoparaffin include 50 to 250, preferably 60 to 230, more preferably 70 to 210, and particularly preferably 80 to 190.

[0016] The average carbon number in this specification is a value derived from the results of peak area and mass analysis measured using a GC-MS (gas chromatography mass spectrometry) measuring device (JMS-T2000GC AccuTOF (registered trademark) GC-Alpha, manufactured by JEOL Ltd.).

[0017] Component (A) can be synthesized, for example, as follows: First, a mixed gas of isobutene and n-butene is treated by a known method, for example, cationic polymerization using a catalyst, to obtain a polymer. The resulting polymer is then hydrogenated to obtain a hydrogenated polymer, which is then purified by adsorption treatment, distillation, and other processes to obtain component (A).

[0018] Specific examples of the component (A) include "Pearlream 18" (average carbon number 72), "Pearlream 24" (average carbon number 96), and "Pearlream 46" (average carbon number 184) (all manufactured by NOF Corporation). One or more of these isoparaffins with different average carbon numbers can be used as the component (A).

[0019] [Component (B)] Component (B) used in the present invention is an isoparaffin having an average carbon number of 20 to 24, in other words, a mixture of medium-chain hydrocarbons having side chains, and is usually obtained by hydrogenating a polymer of isobutene and n-butene. Examples of such components include those generally classified as "liquid isoparaffins" in the cosmetics field.

[0020] If the average number of carbon atoms is less than 20, the sunscreen composition may not feel thick enough when applied in a low-temperature environment, and a tight feeling may be felt over time. On the other hand, if the average number of carbon atoms is more than 24, the sunscreen composition may not be easily spreadable in a low-temperature environment.

[0021] Component (B) can be synthesized, for example, as follows: First, a mixed gas of isobutene and n-butene is treated by a known method, for example, cationic polymerization using a catalyst, to obtain a polymer. The resulting polymer is then hydrogenated to obtain a hydrogenated polymer, which is then purified by adsorption treatment, distillation, and other processes to obtain component (B).

[0022] Specific examples of products of component (B) include "Pearlream 6" (average carbon number: 24), "Pearlream EX" (average carbon number: 20) (both manufactured by NOF Corporation), and "IP Solvent 1620" (average carbon number: 20) (manufactured by Idemitsu Kosan Co., Ltd.) One or more of these isoparaffins having different average carbon numbers can be used as component (B).

[0023] [Component (C)] Component (C) used in the present invention is one or more emulsifiers selected from the group consisting of sorbitan fatty acid esters having an HLB of 2 to 10, fatty acid glyceryls having an HLB of 2 to 10, and polyoxyethylene mono-fatty acid glyceryls having an HLB of 2 to 10.

[0024] The emulsifier of component (C) has a lower limit HLB of 2, preferably 3, and more preferably 4. The upper limit HLB is 10, preferably 8, and more preferably 6. The HLB range can be specified using upper and lower limit values ​​arbitrarily selected from the values ​​listed above. Examples of the HLB of component (C) include 2 to 10, preferably 3 to 8, and more preferably 4 to 6. If the HLB of component (C) falls outside the range specified above, emulsion stability may decrease. The HLB referred to here is an index indicating affinity with water, and is calculated by the following formula according to Griffin (W.C. Griffin: J. Soc. Cosmetic Chemists, 33, 1180 (1960)): HLB = 20 (1 - S / A) (where S is the saponification value of the ester, and A is the neutralization value of the fatty acid). The saponification value and the neutralization value can be measured, for example, according to the method described in "Standard Methods for the Analysis of Fats, Oils and Related Compounds (1)" (Japan Oil Chemists' Association, 1996).

[0025] The fatty acids constituting the sorbitan fatty acid esters, fatty acid glyceryls, and polyoxyethylene monoglyceryl fatty acid esters preferably have 8 to 22 carbon atoms. Furthermore, the fatty acids may be branched or linear, and may be monovalent or divalent or higher polyvalent fatty acids, but are preferably monovalent fatty acids. The fatty acids may be saturated or unsaturated, may have a hydroxyl group, or may be condensed. They may also be mixed fats and oils, which are mixtures of fatty acids. Furthermore, the fatty acids used in the production may contain rosin acid in addition to fatty acids having 8 to 22 carbon atoms, as long as the effects of the present invention are not impaired. The number of carbon atoms in the fatty acids is preferably 12 or more, more preferably 14 or more, and preferably 18 or less. Preferred ranges for the number of carbon atoms in the fatty acids include, in addition to 8 to 22, 12 to 22, 14 to 22, 8 to 18, 12 to 18, and 14 to 18, for example. Examples of fatty acids having 8 to 22 carbon atoms include ethylhexanoic acid, capric acid, lauric acid, myristic acid, palmitic acid, isopalmitic acid, macadamia nut fatty acid, stearic acid, isostearic acid, hydroxystearic acid, oleic acid, behenic acid, etc. Among these, myristic acid, palmitic acid, isopalmitic acid, stearic acid, isostearic acid, and oleic acid are preferred.

[0026] Sorbitan fatty acid esters are esters having a structure in which one hydroxy group of sorbitol or a sorbitol intramolecular condensate forms an ester bond with a fatty acid. Examples of sorbitan fatty acid esters having an HLB of 2 to 10 include commercially available products such as Nonion CP-08R (sorbitan monocaprate (HLB: 9.6)), Nonion LP-20R (sorbitan monolaurate (HLB: 8.6)), Nonion PP-40R pellets (sorbitan monopalmitate (HLB: 6.7)), Nonion SP-60R pellets (sorbitan monostearate (HLB: 4.7)), Nonion OP-80R (sorbitan monooleate (HLB: 4.3)), and Nonion OP-83RAT (sorbitan sesquioleate (HLB: 3.7)) (all manufactured by NOF Corporation).

[0027] Fatty acid glyceryls are esters having a structure in which one hydroxy group of glycerin forms an ester bond with a fatty acid, and polyoxyethylene mono-fatty acid glyceryls are compounds having a structure in which ethylene oxide is added to the remaining two hydroxy groups of the ester. The lower limit of the number of moles of ethylene oxide added in polyoxyethylene mono-fatty acid glyceryls is preferably 5, more preferably 6, and particularly preferably 7, and the upper limit is preferably 30, more preferably 20, and particularly preferably 10. The range of the number of moles of ethylene oxide added can be specified using numerical values ​​arbitrarily selected from the numerical values ​​described above as the upper and lower limits. The number of moles of ethylene oxide added in polyoxyethylene mono-fatty acid glyceryls is, for example, preferably 5 to 30, more preferably 6 to 20, and particularly preferably 7 to 10.

[0028] Examples of fatty acid glyceryls include glyceryl myristate and glyceryl coconut oil fatty acid, and examples of polyoxyethylene monoglyceryl fatty acid glyceryls include polyoxyethylene glyceryl coconut oil fatty acid, polyoxyethylene (caprylic / capric) glyceryl, polyoxyethylene glyceryl laurate, polyoxyethylene glyceryl oleate, and polyoxyethylene glyceryl isostearate. Examples of fatty acid glyceryls having an HLB of 2 to 10 include commercially available products such as NIKKOL MGM (glyceryl myristate (HLB: 3.5)) (manufactured by Nikko Chemicals Co., Ltd.). Component (C) may be used alone or in combination of two or more types selected from these esters, which are emulsifiers.

[0029] [Component (D)] Component (D) used in the present invention is a polyhydric alcohol having 2 to 6 carbon atoms and a valence of 2 to 3, and one or more polyhydric alcohols selected from those satisfying these conditions can be used. Among these, polyhydric alcohols having 2 to 5 carbon atoms are preferred, and 3 to 4 carbon atoms are more preferred. Furthermore, a valence of 3 is preferred. Specific examples include propylene glycol, 1,3-butylene glycol, and glycerin, with 1,3-butylene glycol and glycerin being preferred, and glycerin being more preferred. Divalent or trivalent means having 2 to 3 hydroxy groups in one molecule.

[0030] [Component (E)] Component (E) used in the present invention is an ultraviolet scattering agent blended for the purpose of scattering or blocking ultraviolet rays. The ultraviolet scattering agent is not particularly limited as long as it is one that is commonly used in cosmetics, but for example, at least one selected from the group consisting of titanium oxide, zinc oxide, iron oxide, and cerium oxide is preferred. Among these, titanium oxide and zinc oxide are more preferred.

[0031] These ultraviolet scattering agents preferably have an average primary particle size of 5 nm to 100 nm, more preferably 10 nm to 40 nm. The "average primary particle size" is a value obtained by measuring the particle sizes of 200 randomly selected particles using a transmission electron microscope and calculating the average of the primary particle sizes.

[0032] The shape of the UV scattering agent is not particularly limited, and UV scattering agents having any shape, such as spherical, rod-like, needle-like, spindle-like, or plate-like, can be used. The UV scattering agent may be coated with either an inorganic or organic surface coating, or may be coated with both an inorganic and an organic surface coating. The inorganic surface coating refers to a coating of the surface of the UV scattering agent with, for example, a hydroxide and / or oxide of at least one element selected from silicon, aluminum, zinc, iron, titanium, and zirconium, with aluminum hydroxide being preferred. The organic surface coating refers to a coating of the surface of the UV scattering agent with a known organosilicon compound, such as a known silicone having a hydrogen-silicon bond, such as methylhydrogenpolysiloxane (dimethicone / methicone) copolymer, or triethoxysilylethylpolydimethylsiloxyethyldimethicone having an alkoxy group-silicon bond as a reactive group, with methylhydrogenpolysiloxane (dimethicone / methicone) copolymer being more preferred.

[0033] These ultraviolet scattering agents may be obtained as simple substances and used, or commercially available products in which metal oxides are stably reduced in size in an oil agent may be used. Examples of oil agents used to reduce the size of metal oxide particles include silicone oil, ester oil, and hydrocarbon oil. Examples of such commercially available products include "IOPP60ZIAJ" and "IOPP50TIJ" manufactured by KOBO Dispatec Co., Ltd., and "DIF-3ST2," "DIS-11A," and "STR-100A-LP" manufactured by Sakai Chemical Industry Co., Ltd.

[0034] "IOPP60ZIAJ" manufactured by KOBO Dispatec Co., Ltd. consists of zinc oxide, ethylhexyl palmitate, isostearic acid, and polyhydroxystearic acid, and "IOPP50TIJ" consists of titanium oxide, ethylhexyl palmitate, aluminum hydroxide, isostearic acid, and polyhydroxystearic acid. "DIF-3ST2" manufactured by Sakai Chemical Industry Co., Ltd. consists of zinc oxide, cyclopentasiloxane, and hydrogen dimethicone, "DIS-11A" consists of titanium oxide, cyclopentasiloxane, hydrated silica, aluminum hydroxide, and hydrogen dimethicone, and "STR-100A-LP" consists of titanium oxide, hydrated silica, aluminum hydroxide, and hydrogen dimethicone. The UV scattering agents can be used alone or in combination of two or more.

[0035] [Component (F)] Component (F) used in the present invention is water, and examples thereof include purified water such as ion-exchanged water and distilled water, and tap water, and is preferably purified water such as ion-exchanged water and distilled water.

[0036] [Content of Each Component] The lower limit of the content of component (A) in the sunscreen composition is 2% by mass, preferably 5% by mass, more preferably 10% by mass, and particularly preferably 14% by mass. The upper limit of the content of component (A) is 51% by mass, preferably 35% by mass, more preferably 25% by mass, and particularly preferably 18% by mass. If the content of component (A) is too low, the skin may be prone to a tight feeling over time, and the thick feeling upon application may be difficult to sense in a low-temperature environment. On the other hand, if the content of component (A) is too high, the ease of spreading in a low-temperature environment may decrease. The range of the content of component (A) can be specified using numerical values ​​arbitrarily selected from the upper and lower limits described above. Examples of the content of component (A) include 2 to 51% by mass, preferably 5 to 35% by mass, more preferably 10 to 25% by mass, and particularly preferably 14 to 18% by mass.

[0037] The lower limit of the content of component (B) in the sunscreen composition is 9% by mass, preferably 17% by mass, more preferably 25% by mass, and particularly preferably 33% by mass. The upper limit of the content of component (B) is 80% by mass, preferably 66% by mass, more preferably 52% by mass, and particularly preferably 39% by mass. If the content of component (B) is too low, the ease of spreading the composition in a low-temperature environment may decrease, and a feeling of tightness may be felt over time. On the other hand, if the content of component (B) is too high, it may be difficult to feel a sense of thickness upon application in a low-temperature environment. The range of the content of component (B) can be specified using numerical values ​​arbitrarily selected from the numerical values ​​described above as the upper and lower limits. Examples of the content of component (B) include 9 to 80% by mass, preferably 17 to 66% by mass, more preferably 25 to 52% by mass, and particularly preferably 33 to 39% by mass.

[0038] The lower limit of the content of component (C) in the sunscreen composition is 0.1% by mass, preferably 1% by mass, more preferably 2% by mass, and particularly preferably 3% by mass. The upper limit of the content of component (C) is 14% by mass, preferably 10% by mass, more preferably 8% by mass, and particularly preferably 6% by mass. If the content of component (C) is too low, emulsion stability may be insufficient, while if the content of component (C) is too high, ease of spreadability in low-temperature environments may decrease. The range of the content of component (C) can be specified using numerical values ​​arbitrarily selected from the upper and lower limit values ​​described above. Examples of the content of component (C) include 0.1 to 14% by mass, preferably 1 to 10% by mass, more preferably 2 to 8% by mass, and particularly preferably 3 to 6% by mass.

[0039] The lower limit of the content of component (D) in the sunscreen composition is 0.1% by mass, preferably 1% by mass, more preferably 2% by mass, and particularly preferably 3% by mass. The upper limit of the content of component (D) is 10% by mass, preferably 8% by mass, more preferably 7% by mass, and particularly preferably 6% by mass. If the content of component (D) is too low, it may be difficult to feel the thickness of the composition when applied in a low-temperature environment. On the other hand, if the content of component (D) is too high, the ease of spreading the composition in a low-temperature environment may decrease. The range of the content of component (D) can be specified using numerical values ​​arbitrarily selected from the upper and lower limits described above. Examples of the content of component (D) include 0.1 to 10% by mass, preferably 1 to 8% by mass, more preferably 2 to 8% by mass, particularly preferably 3 to 7% by mass, and even more preferably 3 to 6% by mass.

[0040] The lower limit of the content of component (E) in the sunscreen composition is 5% by mass, preferably 10% by mass, more preferably 15% by mass, and particularly preferably 20% by mass. The upper limit of the content of component (E) is 40% by mass, preferably 35% by mass, more preferably 30% by mass, and particularly preferably 25% by mass. If the content of component (E) is too low, sufficient UV protection effect may not be obtained, while if the content of component (E) is too high, the ease of spreading in low-temperature environments may decrease and a tight feeling may be felt over time. The range of the content of component (E) can be specified using numerical values ​​arbitrarily selected from the numerical values ​​described above as the upper and lower limits. Examples of the content of component (E) include 5 to 40% by mass, preferably 10 to 35% by mass, more preferably 15 to 30% by mass, particularly preferably 20 to 30% by mass, and even more preferably 20 to 25% by mass.

[0041] The lower limit of the content of component (F) in the sunscreen composition is 6% by mass, preferably 10% by mass, more preferably 16% by mass, and particularly preferably 18% by mass. The upper limit of the content of component (F) is 57% by mass, preferably 47% by mass, more preferably 35% by mass, and particularly preferably 25% by mass. If the content of component (F) is too low, the skin may feel tight over time. If the content of component (F) is too high, the emulsion stability may be insufficient, making the skin feel tight over time and making it difficult to feel a thick feeling upon application in a low-temperature environment. The range of the content of component (F) can be specified using numerical values ​​arbitrarily selected from the upper and lower limits listed above. Examples of the content of component (F) include 6 to 57% by mass, preferably 10 to 47% by mass, more preferably 16 to 47% by mass, particularly preferably 18 to 35% by mass, and even more preferably 18 to 25% by mass.

[0042] In the present invention, the lower limit of the mass ratio ((A) / (B)) of component (A) to component (B) is 5 / 95, preferably 10 / 90, and more preferably 20 / 80. The upper limit of the mass ratio ((A) / (B)) is 60 / 40, preferably 50 / 50, and more preferably 40 / 60. If the mass ratio ((A) / (B)) is too small, it may be difficult to feel the thickness upon application in a low-temperature environment, and a tight feeling may be easily felt over time. If the mass ratio ((A) / (B)) is too large, the ease of spreading in a low-temperature environment may decrease. The range of the mass ratio ((A) / (B)) can be specified using mass ratios arbitrarily selected from the mass ratios described above as the upper and lower limits. The mass ratio ((A) / (B)) is, for example, 5 / 95 to 60 / 40, preferably 10 / 90 to 50 / 50, and more preferably 20 / 80 to 40 / 60.

[0043] [Other Components] The sunscreen composition of the present invention can contain various other components as long as the stability of the composition is maintained and the effects of the present invention are not impaired. Examples of such components include oily materials such as vegetable oils and fats, animal oils and fats, waxes, paraffins other than polybutene, petrolatum, fatty acid esters other than component (C), higher fatty acids, and higher alcohols; inorganic compounds such as talc, silica, kaolin, sodium carbonate, and borax; organic solvents such as ethanol, isopropanol, and ethylene glycol; water-soluble polymers such as polyethylene glycol, polypropylene glycol, polyvinyl alcohol, polyvinylpyrrolidone, carboxymethylcellulose, block copolymers of ethylene oxide and propylene oxide, and copolymers of maleic anhydride and methyl vinyl ether; and other additives such as oxidation stabilizers, preservatives / bactericides, colorants, fragrances, pharmaceuticals, and mixtures thereof. The sunscreen composition of the present invention may also contain compounds other than the above-mentioned UV scattering agents contained in commercially available products of the component (E).

[0044] The content of the above-mentioned other components in the sunscreen composition of the present invention can be set according to the amount typically used in cosmetics and the like depending on the purpose, but is typically 20% by mass or less in the composition. The upper limit of the content of the other components is preferably 15% by mass, more preferably 10% by mass, and the lower limit is preferably 0.1% by mass, more preferably 0.5% by mass. A preferred range for the content of the other components can be defined using upper and lower limit values ​​arbitrarily selected from the values ​​listed above. The content of the other components is, for example, preferably 0.1 to 15% by mass, more preferably 0.5 to 10% by mass.

[0045] The content of each component is calculated based on the total content of all components constituting the sunscreen composition, taken as 100% by mass. The total content of components (A) to (F) is preferably 80% by mass or more, more preferably 85% by mass or more, and particularly preferably 90% by mass or more. The content of each component can be adjusted to the desired level by appropriately adjusting the amount of water added.

[0046] [Production of Sunscreen Composition] The sunscreen composition of the present invention can be produced by a known method, for example, by mixing the above-mentioned components and emulsifying them in an emulsifying machine or kneader such as a homogenizer, homomixer, roll tester, or mill at a temperature ranging from room temperature to 90°C for about 10 to 120 minutes depending on the volume.

[0047] The following examples and comparative examples will be used to explain the present invention in more detail, but the present invention is not limited to these examples.

[0048] <Sunscreen Compositions> The sunscreen compositions shown in Table 1 (Examples 1 to 16) and Table 2 (Comparative Examples 1 to 10) were prepared by known methods and evaluated by the following methods. In Tables 1 and 2, the numerical values ​​for each component indicate the content (% by mass) of each component relative to the total amount of the sunscreen composition. Component (A) / Component (B) indicates the content ratio of component (A) to component (B).

[0049] [Component (A)] #1 Hydrogenated polyisobutene: Pearleem 24 (manufactured by NOF Corporation) (average carbon number: 96) #2 Hydrogenated polyisobutene: Pearleem 46 (manufactured by NOF Corporation) (average carbon number: 184) #3 Hydrogenated polyisobutene: Pearleem 18 (manufactured by NOF Corporation) (average carbon number: 72) [Component (B)] #4 Hydrogenated polyisobutene: Pearleem 6 (manufactured by NOF Corporation) (average carbon number: 24) #5 Hydrogenated polyisobutene: Pearleem EX (manufactured by NOF Corporation) (average carbon number: 20) [Component (C)] #6 Sorbitan monooleate: Nonion OP-80R (manufactured by NOF Corporation, HLB: 4.3) #7 Glyceryl myristate: NIKKOL MGM (manufactured by Nikko Chemicals Co., Ltd., HLB: 3.5) [Component (D)] Glycerin: RG-S (manufactured by NOF Corporation) 1,3-butylene glycol: 1,3-butylene glycol-P (manufactured by KH Neochem Co., Ltd.) [Component (E)] #8 UV scattering agent (titanium oxide): STR-100A-LP (manufactured by Sakai Chemical Industry Co., Ltd.) (average primary particle size 15 nm)

[0050] <Evaluation of Sunscreen Compositions> The sunscreen compositions of Examples 1 to 16 and Comparative Examples 1 to 10 were evaluated for thickness upon application, ease of spreading at low temperatures, and lack of tightness over time, as described in (1) to (3) below. The evaluation results are shown in Tables 1 and 2. The panelists conducting the following evaluations had been trained in a preliminary evaluation test conducted prior to the evaluation test to ensure that the level of evaluation corresponding to each score was roughly consistent, thereby preventing differences in evaluation criteria between panelists.

[0051] (1) Thickness upon application Ten male and female panelists, aged between 25 and 55, washed their hands with hand soap, then took 0.2 g of each sunscreen composition that had been stored at 5°C onto their fingertips and applied it to the back of their hands. The panel evaluated the feeling of thickness upon spreading and the feeling that the skin was protected, using the following absolute evaluation criteria. <Absolute evaluation criteria> (Score): (Evaluation) 2 points: Felt very thick. 1 point: Felt somewhat thick. 0 point: Felt no thickness.

[0052] (2) Ease of spreading at low temperatures Ten male and female panelists, aged between 25 and 55, washed their hands with hand soap, then took 0.2 g of each sunscreen composition that had been stored at 5°C onto their fingertips and applied it to the back of their hands. The spreadability was evaluated according to the following absolute evaluation criteria. <Absolute evaluation criteria> (Score): (Evaluation) 2 points: The composition spread very well. 1 point: The composition spread somewhat well. 0 point: The composition spread poorly.

[0053] (3) Absence of tightness over time Ten male and female panelists aged 25 to 55 were assigned to apply 0.2 g of the sunscreen composition stored at 5°C to their fingertips and the composition to the back of their hands. After three hours in an environment with a temperature of 10°C and a humidity of 30%, the panel evaluated whether the skin felt moisturized, similar to that immediately after application, and whether the skin felt tensioned when moving the fingers. During the three hours, a fan was used to blow air onto the back of the hand once every 30 minutes for three minutes each time. The evaluation was performed according to the absolute evaluation criteria below. <Absolute Evaluation Criteria> (Score): (Evaluation) 2 points: No tightness felt. 1 point: A slight tightness felt. 0 point: A very strong tightness felt.

[0054] For each of the evaluations (1) to (3) above, the total score of each panelist was calculated, and a judgment was made based on the total score according to the following evaluation criteria. The evaluations other than "x" (excellent), such as "◎", "◯", and "△" were considered to be pass. ◎: Total score of 17 points or more ○: Total score of 14 points or more but less than 17 points △: Total score of 11 points or more but less than 14 points ×: Total score of less than 11 points

[0055]

[0056]

[0057] The sunscreen compositions of Examples 1 to 16 all had excellent thickness when applied, ease of spreading at low temperatures, and no tight feeling over time.

[0058] In contrast, Comparative Examples 1 to 10 did not achieve sufficient performance. Comparative Example 1 did not contain component (B), so the ease of spreading at low temperatures and the lack of tightness over time were insufficient. Comparative Example 2 did not contain component (A), so the thickness at the time of application and the lack of tightness over time were insufficient. Comparative Example 3 contained more than 14% by mass of component (C), so the ease of spreading at low temperatures was insufficient.

[0059] Comparative Example 4 did not contain component (D), and therefore the thickness upon application was insufficient. Comparative Example 5 contained more than 10% by mass of component (D), and therefore the ease of spreading at low temperatures was insufficient. Comparative Example 6 contained more than 40% by mass of component (E), and therefore the ease of spreading at low temperatures and the lack of tightness over time were insufficient. Comparative Example 7 contained less than 6% by mass of component (F), and therefore the lack of tightness over time was insufficient. Comparative Example 8 contained more than 57% by mass of component (F), and therefore the thickness upon application and the lack of tightness over time were insufficient. Comparative Example 9 had a mass ratio ((A) / (B)) of component (A) to component (B) greater than 60 / 40, and therefore the ease of spreading at low temperatures was insufficient. In Comparative Example 10, the mass ratio of component (A) to component (B) ((A) / (B)) was smaller than 5 / 95, and therefore the thickness upon application and lack of tightness over time were insufficient.

[0060] Next, formulation examples (Formulation Examples 1 and 2) of the sunscreen composition of the present invention are shown. When the sunscreen compositions of these formulation examples were also evaluated according to the above criteria (1) to (3), they were found to be easy to spread while maintaining a thick feel at the time of application even in a low-temperature environment, and furthermore, they were unlikely to cause a tight feeling over time even under dry or windy conditions, providing an excellent feel when used. The mass ratio ((A) / (B)) in the formulation examples below is 34 / 66 for Formulation Example 1 and 36 / 64 for Formulation Example 2. The following formulation examples also used the following component (E): Hydrophobized titanium oxide: STR-100A-LP (manufactured by Sakai Chemical Industry Co., Ltd.) Hydrophobized zinc oxide: FINEX-50LP (manufactured by Sakai Chemical Industry Co., Ltd.)

[0061] Formulation Example 1: Sunscreen Milk (Components) (% by mass) 1. Isoparaffin having an average carbon number of 24 (component (B)) 31.0 2. Hydrophobically treated titanium oxide (component (E)) 21.0 3. Isoparaffin having an average carbon number of 96 (component (A)) 16.0 4. Glycerin (component (D)) 5.0 5. Sorbitan monooleate (component (C)) 5.0 6. (Vinylpyrrolidone / hexadecene) copolymer 2.5 7. Stearic acid 2.0 8. Preservative appropriate amount 9. Fragrance appropriate amount 10. Purified water (component (F)) 17.0 Total 100.0

[0062] Formulation Example 2: Sunscreen Milk (Components) (% by mass) 1. Isoparaffin having an average carbon number of 20 (component (B)) 30.0 2. Isoparaffin having an average carbon number of 72 (component (A)) 17.0 3. Hydrophobized titanium dioxide (component (E)) 11.0 4. Hydrophobized zinc oxide (component (E)) 10.0 5. Glycerin (component (D)) 2.8 6. 1,3-butylene glycol (component (D)) 2.5 7. PEG-32 2.5 8. Sorbitan monooleate (component (C)) 4.5 9. Glyceryl myristate (component (C)) 0.5 10. (Acrylates / C10-30 alkyl acrylate) crosspolymer 0.5 11. Citric acid 0.2 12. Preservatives: Appropriate amount 13. Fragrance: Appropriate amount 14. Purified water (ingredient (F)) 18.0 Total 100.0

[0063] The sunscreen composition of the present invention is easy to spread while maintaining a thick feel at the time of application even in a low-temperature environment, and further, is unlikely to cause a tight feeling over time even under dry or windy conditions, and has an excellent feel when used, and therefore can be suitably used as a sunscreen cosmetic or the like.

Claims

1. A sunscreen composition containing 2 to 51 mass% of component (A), 9 to 80 mass% of component (B), 0.1 to 14 mass% of component (C), 0.1 to 10 mass% of component (D), 5 to 40 mass% of component (E), and 6 to 57 mass% of component (F), in which the mass ratio of component (A) to component (B) ((A) / (B)) is 5 / 95 to 60 / 40. Component (A): Isoparaffin having an average carbon number of 50 to 250 Component (B): Isoparaffin having an average carbon number of 20 to 24 Component (C): One or more emulsifiers selected from the group consisting of sorbitan fatty acid esters having an HLB of 2 to 10, fatty acid glyceryls having an HLB of 2 to 10, and polyoxyethylene mono fatty acid glyceryls having an HLB of 2 to 10 Component (D): Polyhydric alcohols having 2 to 6 carbon atoms and 2 to 3 valences Component (E): Ultraviolet scattering agent Component (F): Water