Water-in-oil type emulsion cosmetic composition

Abstract

Provided is a water-in-oil type emulsion cosmetic composition that exhibits good resistance to caking of ultraviolet scattering agent particles, is excellent in emulsion stability and usability, and once applied, blends well with the skin.　The water-in-oil type emulsion cosmetic composition contains an oily medium, ultraviolet scattering agent particles dispersed in the oily medium, a dispersant of the ultraviolet scattering agent particles, a silicone-based surfactant having an HLB value of 8.0 or less, and water, and satisfies all of the following conditions (I) to (V).　Condition (I): The oily medium contains, at least one of a polar oil and a polar silicone oil, and a non-polar silicone oil, or contains at least one of a polar oil and a polar silicone oil, a hydrocarbon oil, and a non-polar silicone oil. At least a part of the oily medium is a volatile component. Condition (II): The non-polar silicone oil is 55 parts by mass or more with respect to 100 parts by mass of the total oily medium. Condition (III): The dispersant contains polyhydroxystearic acid and / or polyglyceryl polyricinoleate, and the content ratio of the ultraviolet scattering agent particles to the dispersant is 10.0 or less. Condition (IV): The content of the silicone-based surfactant is 3.0 mass% or less. Condition (V): The content ratio of the silicone-based surfactant to the dispersant is less than 1.0.

Description

Water-in-oil emulsion cosmetic composition

[0001] The present invention relates to a water-in-oil emulsion cosmetic composition.

[0002] In general, ultraviolet scattering agent particles are often dispersed in an oily medium and used as an ultraviolet protection agent. However, because ultraviolet scattering agent particles tend to aggregate, various studies have been conducted on the dispersibility, stability, usability, and the like of the particles when they are incorporated into cosmetic compositions.

[0003] For example, Patent Document 1 discloses a composition that maintains good usability while also providing good dispersibility for high-concentration ultraviolet scattering agent particles. More specifically, the composition of Patent Document 1 is a composition in which ultraviolet scattering agent particles are dispersed in a mixture of polar oil, hydrocarbon oil, silicone oil, and polyhydroxystearic acid, wherein the polar oil is 10 parts by mass or more and 70 parts by mass or less per 100 parts by mass of the polar oil, hydrocarbon oil, and silicone oil together; the hydrocarbon oil is 1.0 part by mass or more and 60 parts by mass or less per 100 parts by mass of the polar oil, hydrocarbon oil, and silicone oil together; the silicone oil is 10 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the polar oil, hydrocarbon oil, and silicone oil together; the ultraviolet scattering agent particles are 30 parts by mass or more per 100 parts by mass of the polar oil, hydrocarbon oil, and silicone oil together; and the mass ratio of polyhydroxystearic acid to the ultraviolet scattering agent particles (mass of polyhydroxystearic acid / mass of ultraviolet scattering agent particles) is 0.02 or more, which is a composition, particularly a cosmetic composition.

[0004] Furthermore, Patent Document 2 discloses a cosmetic preparation that has high powder dispersibility, excellent usability, and good stability over time. More specifically, the cosmetic preparation of Patent Document 2 is a powder dispersion composition containing (A) powder, (B) oil, and (C) polyglyceryl polyricinoleate, in which the (B) oil contains (b1) polar oil and (b2) volatile oil, the (b1) polar oil accounts for 35 to 80% by mass of the total amount of the (B) oil, 20% by mass or more of the (b2) volatile oil is a volatile hydrocarbon oil, and the (C) polyglyceryl polyricinoleate is 0.5 to 10% by mass of the total amount of the powder dispersion composition.

[0005] JP 2022-118436 A International Publication No. 2022 / 153928

[0006] However, in compositions such as sunscreen cosmetics, even if the dispersibility of UV scattering agent particles is temporarily improved, the UV scattering agent particles that have settled due to standing may clump together and not return to their original dispersed state even when shaken (i.e., particle caking). Furthermore, cosmetic compositions containing UV scattering agent particles still have room for improvement in terms of emulsion stability, usability, etc.

[0007] The present invention seeks to improve the above-mentioned circumstances, and its object is to provide a water-in-oil emulsion cosmetic composition which has good caking resistance of ultraviolet scattering agent particles, is excellent in emulsion stability and usability, and further has excellent compatibility with the skin after application.

[0008] In the present invention, "excellent compatibility with the skin after application" means that when a cosmetic composition containing ultraviolet scattering agent particles is applied to the skin, it has the effect of being white immediately after application, thereby improving the visibility of the coated surface and making uncoated areas easily visible, thereby making it easy to use. Furthermore, after a certain time (e.g., 1 minute or more, 2 minutes or more, 5 minutes or more, 10 minutes or more, 15 minutes or more, or 20 minutes or more) has passed since its application to the skin, the transparency of the coating film formed on the skin becomes high, i.e., it is less likely to cast a white cast.

[0009] The present invention that achieves the above object is as follows.

[0010] Aspect 1 is a water-in-oil emulsion cosmetic composition comprising: an oily medium; ultraviolet scattering agent particles dispersed in the oily medium; a dispersant for the ultraviolet scattering agent particles; a silicone surfactant having an HLB value of 8.0 or less; and water; and the composition satisfies all of the following conditions (I) to (V): Condition (I) the oily medium contains at least one of a polar oil and a polar silicone oil, and a non-polar silicone oil, or contains at least one of a polar oil and a polar silicone oil, a hydrocarbon oil, and a non-polar silicone oil; and at least a portion of the oily medium is a volatile component; Condition (II) the amount of the non-polar silicone oil is 55 parts by mass or more relative to a total of 100 parts by mass of the oily medium; and Condition (III) the dispersant contains polyhydroxystearic acid and / or polyglyceryl polyricinoleate; The composition according to Aspect 1, wherein the condition (I) is satisfied: the content ratio of the ultraviolet scattering agent particles to the dispersant (mass of the ultraviolet scattering agent particles / mass of the dispersant) is 10.0 or less, condition (IV) the content of the silicone surfactant is 3.0 mass% or less, and condition (V) the content ratio of the silicone surfactant to the dispersant (mass of the silicone surfactant / mass of the dispersant) is less than 1.0. Aspect 2 The composition according to Aspect 1, wherein the condition (I) is satisfied: at least a part of the nonpolar silicone oil is the volatile component. Aspect 3 The composition according to Aspect 1 or 2, wherein the condition (II) is satisfied: the nonpolar silicone oil is 55 parts by mass or more and 83 parts by mass or less, relative to a total of 100 parts by mass of the oil-based medium. Aspect 4: The composition according to any one of Aspects 1 to 3, wherein condition (I) is satisfied: when calculated excluding the volatile components of the oil medium, the amount of the non-polar silicone oil after excluding the volatile components is 40 parts by mass or less per 100 parts by mass of the total oil medium after excluding the volatile components.Aspect 5 The composition according to any one of Aspects 1 to 4, wherein, when calculated excluding the volatile components of the oil medium, the total amount of the polar oil and the polar silicone oil after removal of the volatile components is 20 parts by mass or more per 100 parts by mass of the oil medium after removal of the volatile components, the hydrocarbon oil after removal of the volatile components is 70 parts by mass or less per 100 parts by mass of the oil medium after removal of the volatile components, and the non-polar silicone oil after removal of the volatile components is 40 parts by mass or less per 100 parts by mass of the oil medium after removal of the volatile components, and wherein, in condition (II), the total amount of the polar oil and the polar silicone oil is 10 parts by mass or more per 100 parts by mass of the oil medium, and the hydrocarbon oil is 20 parts by mass or less per 100 parts by mass of the oil medium. Aspect 6: The composition according to any one of Aspects 1 to 5, wherein, in condition (I), the dispersant is present in an amount of 1.0 part by mass or more and 30 parts by mass or less, relative to a total of 100 parts by mass of the oil-based medium and the dispersant after excluding the volatile components, when calculated excluding the volatile components. Aspect 7: The composition according to any one of Aspects 1 to 6, wherein the ultraviolet scattering agent particles are present in an amount of 10 parts by mass or more, relative to a total of 100 parts by mass of the oil-based medium. Aspect 8: The composition according to any one of Aspects 1 to 7, wherein the ultraviolet scattering agent particles are at least one selected from the group consisting of titanium oxide, zinc oxide, iron oxide, and cerium oxide. Aspect 9: The composition according to any one of Aspects 1 to 8, wherein the nonpolar silicone oil comprises a linear nonpolar silicone oil. Aspect 10: The composition according to any one of Aspects 1 to 9, wherein the nonpolar silicone oil comprises dimethicone. Aspect 11: The composition according to aspect 10, wherein the polar silicone oil comprises methylphenylpolysiloxane. Aspect 12: The composition according to any one of aspects 1 to 11, wherein the polar oil does not contain an ultraviolet absorber. Aspect 13: The composition according to any one of aspects 1 to 12, wherein the water content is less than 30% by mass.Aspect 14: The composition according to any one of Aspects 1 to 13, which is a sunscreen cosmetic composition.

[0011] According to the present invention, it is possible to provide a water-in-oil emulsion cosmetic composition which has good caking resistance of ultraviolet scattering agent particles, is excellent in emulsion stability and usability, and further has excellent compatibility with the skin after application.

[0012] FIG. 1 is a graph showing the absorbance from 280 nm to 400 nm immediately after application of the composition of Example 1 and 20 minutes after application.

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the preferred embodiments. However, the present invention is not limited to the following embodiments, and various modifications can be made within the scope of the present invention.

[0014] <Water-in-oil emulsion cosmetic composition> The water-in-oil emulsion cosmetic composition of the present invention (hereinafter also simply referred to as "the composition of the present invention") comprises: an oily medium; ultraviolet scattering agent particles dispersed in the oily medium; a dispersant for the ultraviolet scattering agent particles; a silicone surfactant having an HLB value of 8.0 or less; and water; and satisfies all of the following conditions (I) to (V): Condition (I) the oily medium contains at least one of a polar oil and a polar silicone oil, and a non-polar silicone oil, or contains at least one of a polar oil and a polar silicone oil, a hydrocarbon oil, and a non-polar silicone oil, and at least a portion of the oily medium is a volatile component; Condition (II) the amount of the non-polar silicone oil is 55 parts by mass or more relative to a total of 100 parts by mass of the oily medium; Condition (III) the dispersant contains polyhydroxystearic acid and / or polyglyceryl polyricinoleate, and The content ratio of the ultraviolet scattering agent particles to the dispersant (mass of the ultraviolet scattering agent particles / mass of the dispersant) is 10.0 or less, condition (IV) the content of the silicone surfactant is 3.0 mass% or less, and condition (V) the content ratio of the silicone surfactant to the dispersant (mass of the silicone surfactant / mass of the dispersant) is less than 1.0.

[0015] The composition of the present invention contains the specific components described above and satisfies all of the conditions (I) to (V) described above, and therefore has good caking resistance of the ultraviolet scattering agent particles, excellent emulsion stability and ease of use, and excellent compatibility with the skin after application.

[0016] The composition of the present invention can exhibit the above-mentioned effects by containing the specific components described above and by satisfying all of the above-mentioned conditions (I) to (V). Without being limited by theory, the specific factors that enable the composition of the present invention to exhibit the effects of the present invention are speculated to be as follows.

[0017] According to intensive research by the present inventors, it has been found that in a composition in which ultraviolet scattering agent particles are dispersed, the dispersibility of the ultraviolet scattering agent particles can be improved, but if the dispersibility of the ultraviolet scattering agent particles is improved too much, a caking phenomenon occurs at a certain dispersion state.

[0018] Based on the novel idea of ​​the present inventors, the caking phenomenon of UV scattering agent particles can be prevented by not excessively improving the dispersibility of the UV scattering agent particles in the composition before use (i.e., during storage). It is presumed that after the composition of the present invention is applied to the skin, the composition changes due to the evaporation of some of the components of the oily medium contained therein, thereby further improving the dispersibility of the UV scattering agent particles. The improved dispersibility of the UV scattering agent particles in the composition of the present invention after application to the skin compared to before use can also be said to be one of the effects of "excellent compatibility with the skin after application" as defined in the present invention.

[0019] Another factor that contributes to the excellent caking resistance of the ultraviolet scattering agent particles in the composition of the present invention is thought to be the fact that the content ratio of the silicone surfactant to the dispersant in the above-mentioned condition (V) is adjusted to less than 1.0.

[0020] In the present invention, the caking resistance of the ultraviolet scattering agent particles can be evaluated based on a sedimentation evaluation test. More specifically, the experimental section of the examples described below may be referred to.

[0021] The main factor that enables the composition of the present invention to have excellent emulsion stability is believed to be the incorporation of a silicone surfactant having an HLB value of 8.0 or less into the composition of the present invention.

[0022] In the present invention, the emulsion stability can be evaluated based on a rolling test. More specifically, the experimental section of the examples described below may be referred to.

[0023] The main factor that enables the composition of the present invention to have excellent usability is believed to be that, as specified in the above-mentioned condition (IV), the oil content of the silicone surfactant having an HLB value of 8.0 or less is adjusted to 3.0 mass% or less.

[0024] In the present invention, "usability" can be evaluated comprehensively based on the smoothness when applied to the skin and the presence or absence of a squeaky feeling. More specifically, the experimental section of the examples described below may be referred to.

[0025] The effect of the composition of the present invention, that is, "excellent compatibility with the skin after application," is thought to be mainly due to the use of a volatile component as at least a part of the oily medium, and the change in the composition of the oily medium due to the evaporation of the volatile component of this oily medium after the composition of the present invention is applied to the skin.

[0026] Another factor that contributes to the "good skin compatibility after application" of the composition of the present invention is thought to be that the content ratio of ultraviolet scattering agent particles to dispersant is adjusted to 10.0 or less, as specified in the above-mentioned condition (III).

[0027] In the present invention, the effect of "excellent compatibility with the skin after application" can be evaluated, for example, by the change in absorbance between the initial state and after a certain period of time. More specifically, the experimental section of the examples described below may be referred to.

[0028] In this specification, it should be understood that when two or more types of such components are contained, descriptions regarding the amount of each component (its content, mass ratio to other components, etc.) such as the oily medium, UV scattering agent particles, dispersant, silicone surfactant, polar oil, hydrocarbon oil, polar silicone oil, non-polar silicone oil, volatile component, etc. refer to the total amount thereof.

[0029] <Oil-Based Medium> The composition of the present invention contains an oil-based medium.

[0030] The oily medium of the present invention comprises at least one of polar oil and polar silicone oil, and non-polar silicone oil, or comprises at least one of polar oil and polar silicone oil, hydrocarbon oil, and non-polar silicone oil.That is, the oily medium of the present invention essentially comprises at least one of polar oil and polar silicone oil, and non-polar silicone oil, but may or may not contain hydrocarbon oil.In addition, at least a part of the oily medium of the present invention is volatile component.

[0031] In the present invention, the term "volatile" of an oil medium refers to one that exhibits a volatile content of more than 20% when left at atmospheric pressure and 30°C for 120 minutes. Correspondingly, in the present invention, the term "non-volatile" of an oil medium refers to one that exhibits a volatile content of 20% or less when left at atmospheric pressure and 30°C for 120 minutes.

[0032] In the present invention, the volatility can be evaluated by the following method: ２ The weight is measured before and after leaving it on a precision balance at 30°C for 120 minutes. The amount of oil lost due to volatilization is calculated from the difference in weight before and after leaving it for 120 minutes, and the ratio (%) to the applied weight is evaluated.

[0033] (Polar Oil) The composition of the present invention may contain a polar oil. Note that, when the composition of the present invention does not contain a polar silicone oil, it contains a polar oil. Here, "polar oil" refers to an oil with high polarity among oils usable in cosmetics other than silicone oil, and refers to, for example, an oil having an IOB value of 0.10 or more, 0.11 or more, 0.12 or more, or 0.13 or more. Furthermore, the IOB value of the polar oil according to the present invention may be 0.50 or less, 0.45 or less, or 0.40 or less. Note that the IOB value is an abbreviation for Inorganic / Organic Balance (inorganic / organic ratio), and is a value representing the ratio of the inorganic value to the organic value, and is an index indicating the degree of polarity of an organic compound. Specifically, the IOB value is expressed as IOB value = inorganic value / organic value. The "inorganic value" and "organic value" are set according to the type of atom or functional group, such as 20 for one carbon atom in a molecule and 100 for one hydroxyl group. The IOB value of an organic compound can be calculated by integrating the "inorganic values" and "organic values" of all atoms and functional groups in the organic compound (see, for example, "Organic Conceptual Diagram - Fundamentals and Applications" by Yoshio Koda, pp. 11-17, Sankyo Publishing, 1984).

[0034] In the composition of the present invention, the polar oil may be a volatile polar oil, a non-volatile polar oil, or a mixture thereof. Note that most polar oils used in cosmetics are non-volatile.

[0035] In the composition of the present invention, the content of polar oil is not particularly limited, but from the viewpoint of the dispersibility of ultraviolet scattering agent particles, polar oil may be, for example, 10 parts by mass or more relative to the total 100 parts by mass of oil medium.More specifically, in the composition of the present invention, polar oil may be, for example, 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, 25 parts by mass or more, or 30 parts by mass or more relative to the total 100 parts by mass of oil medium, and may be 45 parts by mass or less, 40 parts by mass or less, 35 parts by mass or less, or 30 parts by mass or less.It should be noted that when the composition of the present invention contains both polar oil and polar silicone oil, the total of polar oil and polar silicone oil may be, for the total 100 parts by mass of oil medium, 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, 25 parts by mass or more, or 30 parts by mass or less, and may be 45 parts by mass or less, 40 parts by mass or less, 35 parts by mass or less, or 30 parts by mass or less.

[0036] Further, when calculating excluding the volatile components of the oil medium, the polar oil after removing the volatile components is 20 parts by mass or more, 25 parts by mass or more, 30 parts by mass or more, 35 parts by mass or more, 45 parts by mass or more, 50 parts by mass or more, 55 parts by mass or more, 60 parts by mass or more, 65 parts by mass or more, 70 parts by mass or more, 75 parts by mass or more, 80 parts by mass or more, 85 parts by mass or more, 90 parts by mass or more, 95 parts by mass or more, or 100 parts by mass (that is, all of the oil medium after removing the volatile components is the polar oil after removing the volatile components). In addition, when the composition of the present invention contains both a polar oil and a polar silicone oil, when calculated excluding the volatile components of the oil medium, the total of the polar oil and polar silicone oil after removing the volatile components may be 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, 25 parts by mass or more, or 30 parts by mass or more, relative to 100 parts by mass of the total oil medium after removing the volatile components, and may be 45 parts by mass or less, 40 parts by mass or less, 35 parts by mass or less, or 30 parts by mass or less.

[0037] In the present invention, the phrase "when calculated excluding the volatile components of the oily medium" can be considered to correspond to the change in the composition of the oily medium due to the evaporation of the volatile components contained in the oily medium after the composition of the present invention is applied to the skin.

[0038] In the present invention, the polar oil may contain, for example, an ester oil, an ultraviolet absorber, or a mixture thereof. However, from the viewpoint of obtaining a non-sticky feel when used, it is preferable that the polar oil does not contain an ultraviolet absorber.

[0039] Ester Oils Specific examples of ester oils that can be used as polar oils in the present invention include tripropylene glycol dineopentanoate, isononyl isononanoate, isopropyl myristate, cetyl octanoate, octyldodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, cetyl lactate, myristyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, cholesteryl 12-hydroxystearate, cetyl ethylhexanoate, ethylene glycol di-2-ethylhexanoate, dipentaerythritol fatty acid esters, N-alkyl glycol monoisostearate, neopentyl glycol dicaprate, diisostearyl malate, glycerin di-2-heptylundecanoate, trimethylolpropane tri-2-ethylhexanoate, trimethylolpropane triisostearate, tetra- Pentaerythrityl 2-ethylhexanoate, triethylhexanoin (glycerin tri-2-ethylhexanoate), glycerin trioctanoate, glycerin triisopalmitate, trimethylolpropane triisostearate, cetyl 2-ethylhexanoate, 2-ethylhexyl palmitate, glycerin trimyristate, tri-2-heptylundecanoic acid glyceride, castor oil fatty acid methyl ester, oleyl oleate, acetoglyceride, palmitic acid Examples of suitable oleic acid surfactants include, but are not limited to, 2-heptylundecyl oleate, diisobutyl adipate, N-lauroyl-L-glutamic acid 2-octyldodecyl ester, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebacate, 2-hexyldecyl myristate, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl sebacate, 2-ethylhexyl succinate, and triethyl citrate.

[0040] In the present invention, the amount of ester oil contained in the polar oil may be, for example, 50 parts by mass or more, 60 parts by mass or more, 70 parts by mass or more, 80 parts by mass or more, 90 parts by mass or more, or 100 parts by mass relative to 100 parts by mass of the total polar oils (i.e., all of the polar oil is ester oil).

[0041] In the present invention, examples of ultraviolet absorbers include, but are not limited to, benzoic acid derivatives, salicylic acid derivatives, cinnamic acid derivatives, dibenzoylmethane derivatives, β,β-diphenylacrylate derivatives, benzophenone derivatives, benzylidene camphor derivatives, phenylbenzimidazole derivatives, triazine derivatives, phenylbenzotriazole derivatives, anthranil derivatives, imidazoline derivatives, benzalmalonate derivatives, 4,4-diarylbutadiene derivatives, etc. Among these, for example, those having a relatively large molecular weight, which are difficult to absorb subcutaneously, or those which are low-irritation are preferably used.

[0042] Specific examples of more preferred ultraviolet absorbers include, but are not limited to, bisethylhexyloxyphenol methoxyphenyl triazine (Tinosorb (registered trademark) S), methylene bisbenzotriazolyl tetramethylbutylphenol (Tinosorb (registered trademark) M), diethylamino hydroxybenzoyl hexyl benzoate (Uvinal Uvinal A Plus A Plus), ethylhexyl triazone (Uvinal Uvinal A Plus T150), terephthalylidene dicamphorsulfonic acid (Megizolil (registered trademark) SX), and drometrizole trisiloxane (Megizolil (registered trademark) XL).

[0043] The polar oil of the present invention preferably does not contain an ultraviolet absorber. However, when an ultraviolet absorber is contained, the content thereof may be, for example, 0.05 parts by mass or more, 0.1 parts by mass or more, or 0.5 parts by mass or more, relative to a total of 100 parts by mass of the polar oil, and may be 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, 10 parts by mass or less, 5.0 parts by mass or less, or 1.0 part by mass or less.

[0044] (Silicone oil) In the present invention, silicone oil can be classified into polar silicone oil and non-polar silicone oil.Here, "non-polar silicone oil" refers to the silicone oil that has a main skeleton based on siloxane bonds among the oils that can be used in cosmetics, and is not modified or modified with polar functional groups or functional groups that are compatible with the above-mentioned polar oils.In contrast, "polar silicone oil" refers to the silicone oil that has a main skeleton based on siloxane bonds, but is modified or modified with polar functional groups or functional groups that are compatible with the above-mentioned polar oils.

[0045] The composition of the present invention contains a non-polar silicone oil, and when the composition of the present invention does not contain the above-mentioned polar oil, it contains a polar silicone oil.

[0046] In the composition of the present invention, as polar silicone oil and non-polar silicone oil, volatile polar silicone oil and non-polar silicone oil can be used, non-volatile polar silicone oil and non-polar silicone oil can be used, or their mixture can be used.From the viewpoint of improving the effect of the present invention, it is preferred that the composition of the present invention comprises volatile non-polar silicone oil.In other words, it is preferred that in the composition of the present invention, at least a part of non-polar silicone oil is volatile component.In addition, when the composition of the present invention comprises polar silicone oil, it is preferred that this polar silicone oil is non-volatile.

[0047] In the composition of the present invention, for example, from the viewpoint of improving caking resistance, the non-polar silicone oil is 55 parts by mass or more relative to 100 parts by mass of the total oil medium. More specifically, the non-polar silicone oil may be 55 parts by mass or more, 60 parts by mass or more, 65 parts by mass or more, or 70 parts by mass or more relative to 100 parts by mass of the total oil medium, and may be 83 parts by mass or less, 80 parts by mass or less, 75 parts by mass or less, 70 parts by mass or less, 65 parts by mass or less, or 60 parts by mass or less.

[0048] In addition, when calculating after excluding the volatile components in oily medium, the content of non-polar silicone oil after excluding volatile components is not particularly limited, relative to the total 100 parts by mass of the oily medium after excluding volatile components.In addition, when calculating after excluding the volatile components in oily medium, the content of non-polar silicone oil after excluding volatile components can be 40 parts by mass or less, 35 parts by mass or less, 30 parts by mass or less, 25 parts by mass or less, 20 parts by mass or less, 15 parts by mass or less, 10 parts by mass or less, 5.0 parts by mass or less, 1.0 parts by mass or less or 0 parts by mass (that is, all of the non-polar silicone oil is volatile), and can also be 0.1 parts by mass or more, 0.5 parts by mass or more, 1.0 parts by mass or more, 5.0 parts by mass or more or 10 parts by mass or more.When calculating after excluding the volatile components in oily medium, the content of non-polar silicone oil is preferably within the above-mentioned range, from the viewpoint of improving the dispersibility of ultraviolet scattering agent particles after applying the composition of the present invention to skin.

[0049] In the present invention, the non-polar silicone oil may be an acyclic non-polar silicone oil (i.e., a chain non-polar silicone oil, preferably a linear non-polar silicone oil) or a cyclic non-polar silicone oil. Of these, acyclic non-polar silicone oils are preferably used, for example, from the viewpoint of improving usability.

[0050] In the present invention, specific examples of non-polar silicone oils include, but are not limited to, linear silicone oils such as polydimethylsiloxane (also referred to as "dimethicone") and methylhydrogenpolysiloxane, cyclic silicone oils such as octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, and dodecamethylcyclohexasiloxane, and mixtures of two or more thereof. Among polydimethylsiloxanes (dimethicones), for example, "Dimethicone 1cs (Octamethyltrisiloxane)," "Dimethicone 1.5cs (Decamethyltetrasiloxane)," and "Dimethicone 2.0cs" may be used as volatile components, while "Dimethicone 6cs" and "Dimethicone 10cs" may be used as non-volatile components.

[0051] In the present invention, specific examples of polar silicone oils include, but are not limited to, phenyl trimethicone, diphenylsiloxyphenyl trimethicone (also referred to as "methylphenyl polysiloxane").

[0052] In addition, when the composition of the present invention contains polar silicone oil, its content is not particularly limited, and for example, can be, for example, 10 parts by mass or more, relative to the total 100 parts by mass of oily medium.In addition, in the composition of the present invention, polar silicone oil can be, relative to the total 100 parts by mass of oily medium, 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, 25 parts by mass or more, or 30 parts by mass or more, and can be 45 parts by mass or less, 40 parts by mass or less, 35 parts by mass or less, or 30 parts by mass or less.In addition, when the composition of the present invention contains both polar oil and polar silicone oil, the total of polar oil and polar silicone oil can be, relative to the total 100 parts by mass of oily medium, 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, 25 parts by mass or more, or 30 parts by mass or more, and can be 45 parts by mass or less, 40 parts by mass or less, 35 parts by mass or less, or 30 parts by mass or less.

[0053] Furthermore, when calculating excluding volatile components of the oil medium, the polar silicone oil after removing the volatile components may be 20 parts by mass or more, 25 parts by mass or more, 30 parts by mass or more, 35 parts by mass or more, 45 parts by mass or more, 50 parts by mass or more, 55 parts by mass or more, 60 parts by mass or more, 65 parts by mass or more, 70 parts by mass or more, 75 parts by mass or more, 80 parts by mass or more, 85 parts by mass or more, 90 parts by mass or more, 95 parts by mass or more, or 100 parts by mass, relative to a total of 100 parts by mass of the oil medium after removing the volatile components (i.e., the entire oil medium after removing the volatile components is the polar silicone oil after removing the volatile components). In addition, when the composition of the present invention contains both a polar oil and a polar silicone oil, when calculated excluding the volatile components of the oil medium, the total of the polar oil and polar silicone oil after removing the volatile components may be 10 parts by mass or more, 15 parts by mass or more, 20 parts by mass or more, 25 parts by mass or more, or 30 parts by mass or more, relative to 100 parts by mass of the total oil medium after removing the volatile components, and may be 45 parts by mass or less, 40 parts by mass or less, 35 parts by mass or less, or 30 parts by mass or less.

[0054] (Hydrocarbon Oil) The composition of the present invention may optionally contain a hydrocarbon oil, where "hydrocarbon oil" refers to a hydrocarbon oil other than a polar oil.

[0055] In the present invention, the hydrocarbon oil may be a volatile hydrocarbon oil, a non-volatile hydrocarbon oil, or a mixture thereof.

[0056] When a hydrocarbon oil is contained in the composition of the present invention, the hydrocarbon oil may be present in an amount of 0.1 parts by mass or more, 0.5 parts by mass or more, 1.0 parts by mass or more, 2.0 parts by mass or more, 3.0 parts by mass or more, 4.0 parts by mass or more, 5.0 parts by mass or more, 6.0 parts by mass or more, 7.0 parts by mass or more, or 8.0 parts by mass or more, relative to a total of 100 parts by mass of the oil medium, and may be present in an amount of 20 parts by mass or less, 19 parts by mass or less, 18 parts by mass or less, 17 parts by mass or less, 16 parts by mass or less, 15 parts by mass or less, or 14 parts by mass or less.

[0057] Furthermore, when a hydrocarbon oil is contained in the composition of the present invention, when calculated excluding volatile components of the oil medium, the hydrocarbon oil after removing the volatile components may be 70 parts by mass or less, 60 parts by mass or less, 50 parts by mass or less, 40 parts by mass or less, 30 parts by mass or less, 20 parts by mass or less, 10 parts by mass or less, 5.0 parts by mass or less, 1.0 part by mass or less, or 0 parts by mass (i.e., all of the hydrocarbon oil is volatile), relative to a total of 100 parts by mass of the oil medium after removing the volatile components, or may be 0.1 parts by mass or more, 0.5 parts by mass or more, 1.0 part by mass or more, 5.0 parts by mass or more, or 10 parts by mass or more.

[0058] In the present invention, specific examples of hydrocarbon oils include, but are not limited to, decane, dodecane, isododecane, isohexadecane, undecane, tridecane, liquid paraffin, olefin oligomer, squalane, squalene, paraffin, and mixtures of two or more thereof.

[0059] <Ultraviolet Scattering Agent Particles> The composition of the present invention contains ultraviolet scattering agent particles.

[0060] In the composition of the present invention, the ultraviolet scattering agent particles are dispersed in an oily medium. More specifically, the ultraviolet scattering agent particles are dispersed in a mixture of an oily medium and a dispersant for the ultraviolet scattering agent particles (i.e., a dispersant containing polyhydroxystearic acid and / or polyglyceryl polyricinoleate). More specifically, by forming a state in which the dispersant for the ultraviolet scattering agent particles is adsorbed and oriented at the interface between the ultraviolet scattering agent particles and the oily medium, the inter-particle interaction between the ultraviolet scattering agent particles in the oily medium is controlled, which is thought to improve the dispersibility and caking resistance of the ultraviolet scattering agent particles.

[0061] The content of the ultraviolet scattering agent particles is not particularly limited, and may be, for example, 10 parts by mass or more relative to a total of 100 parts by mass of the oil-based medium.From the viewpoint of obtaining a higher SPF, the ultraviolet scattering agent particles may be 10 parts by mass or more, 20 parts by mass or more, or 25 parts by mass or more relative to a total of 100 parts by mass of the oil-based medium.In addition, the upper limit of the amount of the ultraviolet scattering agent particles dispersed in the oil-based medium is not particularly limited, and for example, the ultraviolet scattering agent particles may be 200 parts by mass or less, 100 parts by mass or less, 50 parts by mass or less, or 30 parts by mass or less relative to a total of 100 parts by mass of the oil-based medium.

[0062] In the present invention, the ultraviolet scattering agent particles are not particularly limited as long as they have an ultraviolet protection effect, and may be, for example, at least one selected from the group consisting of titanium oxide, zinc oxide, iron oxide, and cerium oxide.

[0063] The ultraviolet scattering agent particles may be hydrophobized or untreated. Here, the hydrophobization treatment may be carried out using a known surface treatment agent for hydrophobization, and examples thereof include fluorine compound treatment, silicone treatment, silicone resin treatment, pendant treatment, silane coupling agent treatment, titanium coupling agent treatment, oil treatment, N-acylated lysine treatment, polyacrylic acid treatment, metal soap treatment, dextrin fatty acid ester treatment, amino acid treatment, inorganic compound treatment, plasma treatment, mechanochemical treatment, silane compound treatment, and silazane compound treatment. Among these treatments, from the viewpoint of dispersion stability and the like, treatment with silicone or silicone resin, treatment with a silane compound or silazane compound, and metal soap treatment such as stearic acid / aluminum hydroxide are preferred.

[0064] The average primary particle diameter of the ultraviolet scattering agent particles is not particularly limited and may be, for example, 5 nm or more, 10 nm or more, or 15 nm or more, or 200 nm or less, 100 nm or less, or 50 nm or less. The "average primary particle diameter" may be determined as the diameter of a circle equivalent to the projected area of ​​the primary particles in a TEM image.

[0065] The shape of the ultraviolet scattering agent particles is not particularly limited, and examples thereof include spherical, plate-like, rod-like, spindle-like, needle-like, and irregular shapes.

[0066] <Dispersant for UV Scattering Agent Particles> The composition of the present invention contains a dispersant for UV scattering agent particles.

[0067] In the composition of the present invention, the dispersant for the ultraviolet scattering agent particles mainly serves to uniformly disperse the ultraviolet scattering agent particles in the oil medium.

[0068] In the composition of the present invention, the content ratio of the ultraviolet scattering agent particles to the dispersant for the ultraviolet scattering agent particles (mass of the ultraviolet scattering agent particles / mass of the dispersant for the ultraviolet scattering agent particles) is 10.0 or less. Here, this content ratio of 10.0 or less is preferred from the viewpoint of more easily achieving "good skin compatibility after application" and from the viewpoint of better dispersing the ultraviolet scattering agent particles. More specifically, in the composition of the present invention, the content ratio of the ultraviolet scattering agent particles to the dispersant for the ultraviolet scattering agent particles may be, for example, 10.0 or less, 9.0 or less, 8.0 or less, 7.0 or less, 6.0 or less, 5.0 or less, or 4.0 or less, or may be 1.0 or more, 2.0 or more, 3.0 or more, or 4.0 or more.

[0069] Furthermore, when calculating excluding volatile components of the oil medium, the amount of the dispersant for the ultraviolet scattering agent particles relative to a total of 100 parts by mass of the oil medium and the dispersant for the ultraviolet scattering agent particles after excluding the volatile components may be, for example, 1.0 parts by mass or more, 1.5 parts by mass or more, 2.0 parts by mass or more, 2.5 parts by mass or more, 3.0 parts by mass or more, 3.5 parts by mass or more, 4.0 parts by mass or more, 4.5 parts by mass or more, 5.0 parts by mass or more, 5.5 parts by mass or more, 6.0 parts by mass or more, 6.5 parts by mass or more, 7.0 parts by mass or more, 7.5 parts by mass or more, 8.0 parts by mass or more, 8.5 parts by mass or more, 9.0 parts by mass or more, 9.5 parts by mass or more, or 10 parts by mass or more, or may be 30 parts by mass or less, 25 parts by mass or less, 20 parts by mass or less, 15 parts by mass or less, 14 parts by mass or less, 13 parts by mass or less, 12 parts by mass or less, 11 parts by mass or less, or 10 parts by mass or less.

[0070] In the present invention, the dispersant for the ultraviolet scattering agent particles contains polyhydroxystearic acid and / or polyglyceryl polyricinoleate.

[0071] (Polyhydroxystearic acid) Polyhydroxystearic acid is a compound in which hydroxystearic acid is oligomerized by forming an ester bond. The degree of polymerization of polyhydroxystearic acid is not particularly limited and may be, for example, 4 to 8.

[0072] Commercially available polyhydroxystearic acid products can be used, and examples of commercially available products include HS Oligomer 600 (manufactured by Toyokuni Oil Mills Co., Ltd.) and Salacos HS-6C (manufactured by Nisshin Oillio Co., Ltd.), but are not limited to these.

[0073] (Polyglyceryl polyricinoleate) Polyglyceryl polyricinoleate is an ester of a condensation product (condensed ricinoleic acid) in which ricinoleic acids, which are higher fatty acids having 18 carbon atoms, are ester-bonded to each other, and polyglycerin having an average degree of polymerization of 2 to 10. A typical example is polyglyceryl-6 polyricinoleate.

[0074] Commercially available polyglyceryl polyricinoleate products can be used, and examples of commercially available products include NIKKOL Decaglyn PR-20 (Nikko Chemicals Co., Ltd.), SY Glystar CR-310, CR-500, CRS-75 (all manufactured by Sakamoto Pharmaceutical Co., Ltd.), but are not limited to these.

[0075] <Silicone-Based Surfactant with an HLB Value of 8.0 or Less> The composition of the present invention contains a silicone-based surfactant with an HLB value of 8.0 or less.

[0076] A silicone surfactant is a nonionic surfactant having a silicone structure (hydrophobic portion) and a hydrophilic portion in the molecule. In the composition of the present invention, a silicone surfactant having an HLB value of 8.0 or less can improve emulsion stability.

[0077] Here, HLB (hydrophilic-lipophilic balance) indicates the molecular weight of the hydrophilic group portion relative to the total molecular weight of the surfactant, and for silicone surfactants, it is determined by Griffin's formula. The HLB value of a mixed surfactant composed of two or more silicone surfactants is determined as follows: The HLB value of a mixed surfactant is the arithmetic average of the HLB values ​​of the individual silicone surfactants based on their blending ratios. Mixed HLB value = Σ (HLBx × Wx) / ΣWx In the formula, HLBx indicates the HLB value of silicone surfactant X. Furthermore, Wx indicates the weight (g) of silicone surfactant X having the value of HLBx.

[0078] In the present invention, the silicone surfactant may have an HLB value of 8.0 or less. More specifically, the HLB value may be, for example, 8.0 or less, 7.5 or less, 7.0 or less, 6.5 or less, 6.0 or less, 5.5 or less, 5.0 or less, 4.5 or less, 4.0 or less, 3.5 or less, 3.0 or less, or 2.5 or less; or may be 0.5 or more, 1.0 or more, 1.5 or more, 2.0 or more, 2.5 or more, 3.0 or more, 3.5 or more, or 3.8 or more.

[0079] In the present invention, the structure of the silicone surfactant is not particularly limited and may be, for example, a linear, branched, or copolymer type. The silicone surfactant may have an HLB value of 8.0 or less, and examples thereof include, but are not limited to, polyether-modified silicone, polyglyceryl-modified silicone, glyceryl-modified silicone, polyether / alkyl-co-modified silicone, and polyglycerin / alkyl-co-modified silicone. More specific examples of silicone surfactants include, but are not limited to, PEG-10 dimethicone (HLB value 2.0), lauryl PEG-9 polydimethylsiloxyethyl dimethicone (HLB value 2.8), PEG-9 polydimethylsiloxyethyl dimethicone (HLB value 3.8), and PEG-12 dimethicone (HLB value 8.0).

[0080] In the composition of the present invention, the silicone surfactant having an HLB value of 8.0 or less is 3.0% by mass or less. This content of 3.0% by mass or less is particularly preferred from the viewpoint of improving the usability of the composition of the present invention. More specifically, the content of the silicone surfactant having an HLB value of 8.0 or less may be 3.0% by mass or less, 2.5% by mass or less, 2.0% by mass or less, 1.5% by mass or less, 1.0% by mass or less, 0.5% by mass or less, or 0.3% by mass or less, or may be 0.1% by mass or more, 0.2% by mass or more, 0.3% by mass or more, 0.4% by mass or more, or 0.5% by mass or more, based on the total mass of the composition.

[0081] In addition, in the composition of the present invention, the content ratio of the silicone surfactant having an HLB value of 8.0 or less to the dispersant for the UV scattering agent particles (mass of silicone surfactant with an HLB value of 8.0 or less / mass of dispersant for UV scattering agent particles) is less than 1.0. This content ratio of less than 1.0 is particularly preferable from the viewpoint of improving the caking resistance of the UV scattering agent particles. Furthermore, if the content of the silicone surfactant having an HLB value of 8.0 or less is greater than the content of the dispersant for the UV scattering agent particles, it may affect the dispersion state of the UV scattering agent particles. More specifically, in the composition of the present invention, the content ratio of the silicone surfactant having an HLB value of 8.0 or less to the dispersant for the above-mentioned ultraviolet scattering agent particles may be less than 1.0, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, 0.5 or less, 0.4 or less, 0.3 or less, 0.2 or less, 0.1 or less, 0.09 or less, 0.08 or less, 0.07 or less, or 0.06 or less, or may be 0.01 or more, 0.02 or more, 0.03 or more, 0.04 or more, 0.05 or more, 0.06 or more, 0.07 or more, 0.08 or more, 0.09 or more, 0.1 or more, or 0.15 or more.

[0082] <Water> The composition of the present invention is a water-in-oil emulsion cosmetic composition and therefore contains water.

[0083] The water used in the composition of the present invention is not particularly limited and may be, for example, water used in cosmetics and quasi-drugs. Specifically, for example, ion-exchanged water, distilled water, ultrapure water, and tap water can be used.

[0084] The water content is not particularly limited and may be, for example, 1.0% by mass or more, 5.0% by mass or more, or 10% by mass or more, and may be less than 30% by mass, 25% by mass or less, 20% by mass or less, or 10% by mass or less, relative to the entire composition.

[0085] <Other Components> The composition of the present invention may further contain other components as long as the effects of the present invention are not impaired. Examples of other components include, but are not limited to, aqueous components other than water, other surfactants, thickeners, other powders, etc. Below, other components will be described by way of example, but the present invention is not limited to these components.

[0086] (Aqueous Components Other Than Water) Examples of aqueous components other than water include, but are not limited to, monohydric alcohols such as ethanol, polyhydric alcohols such as butylene glycol, dipropylene glycol, propanediol, pentylene glycol, hexanediol, and glycerin, polyalkylene glycols such as polyethylene glycol and polypropylene glycol, copolymers thereof, inorganic salts such as sodium chloride and magnesium chloride, and mixtures thereof.

[0087] When the composition of the present invention contains aqueous components other than water, these aqueous components other than water may be present mainly in the aqueous phase.

[0088] The other surfactant refers to a surfactant other than the silicone surfactant having an HLB value of 8.0 or less. Specific examples of the other surfactant include, but are not limited to, nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants.

[0089] Thickener The thickener may be a hydrophilic thickener, a lipophilic thickener, or a mixture thereof.

[0090] Hydrophilic thickeners include, but are not limited to, water-soluble or water-dispersible thickening polymers, and lipophilic thickeners include, but are not limited to, organophilic modified clays such as disteardimonium hectorite.

[0091] (Other Powders) Examples of other powders include, but are not limited to, lustrous color pigments such as red iron oxide, yellow iron oxide, black iron oxide, titanium mica, iron oxide-coated titanium mica, and titanium oxide-coated glass flakes; inorganic powders and usability-adjusting powders such as mica, talc, kaolin, sericite, zinc oxide, and silica; and organic powders such as polyethylene powder, nylon powder, cross-linked polystyrene, cellulose powder, and silicone powder.

[0092] <Method for producing the composition of the present invention> The composition of the present invention can be produced using a conventional method for producing water-in-oil emulsion cosmetics, and the emulsification method is not particularly limited. For example, there is a method in which the aqueous phase and the oil phase are heated as necessary, the aqueous phase is gradually added to the oil phase, and emulsified in an emulsifier, and if heated, the method is allowed to cool to room temperature. In particular, in an embodiment of the composition of the present invention that does not contain solid oil, the heating step is not required, and the process can be simplified.

[0093] A dispersing device may be used to disperse the ultraviolet scattering agent particles in the oil-based medium. Examples of the dispersing device include media-type dispersing devices such as a bead mill, sand mill, ball mill, or paint shaker, high-speed agitators such as a homogenizer or disperser, and media-less dispersing devices such as a high-pressure disperser or ultrasonic disperser. Bead mills are available in horizontal and vertical types, and either type may be used. In general, a dispersion composition with good storage stability can be obtained when the temperature of the dispersion during dispersion is low. For example, dispersion may be performed so that the temperature of the dispersion is 10°C to 40°C.

[0094] <Uses of the Composition of the Present Invention> The composition of the present invention can be widely applied to various types of cosmetics, and can be suitably used, for example, as a cosmetic or a raw material thereof. For example, the composition of the present invention may be a sunscreen cosmetic composition.

[0095] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0096] Examples 1 to 11 and Comparative Examples 1 to 8 Water-in-oil emulsion cosmetic compositions of Examples 1 to 11 and Comparative Examples 1 to 8 were prepared based on the formulations shown in Tables 1 to 4 below. Each of the obtained water-in-oil emulsion cosmetic compositions was evaluated for "skin compatibility after application," "emulsion stability," "caking resistance," and "usability" according to the following criteria, and the results are shown in Tables 1 to 4. For ease of comparison, some examples may be shown multiple times in Tables 1 to 4.

[0097] <Skin Compatibility After Application> A drop of the composition was applied to a 5 cm square quartz plate and coated with a bar coater to a film thickness of 10 μm. The transmittance in the range of 280 nm to 500 nm was quickly measured using a spectrophotometer. The plate was removed and allowed to dry for 20 minutes, after which the same transmittance measurement was performed again. The absorbance was calculated from the initial measurement result and the measurement result after 20 minutes, and the change in absorbance at a wavelength of 400 nm, which corresponds to the visible light range, was compared. In other words, if this change is negative, the visible transparency of the coating film improved, resulting in a change in skin compatibility that was better. "A": The absorbance after 20 minutes decreased by 20% or more; "B": The absorbance after 20 minutes decreased by 10% or more but less than 20%; "C": The absorbance after 20 minutes decreased by 0% or more but less than 10%; "D": The absorbance after 20 minutes did not decrease.

[0098] <Emulsion Stability> Emulsion stability of each of the compositions obtained in the Examples and Comparative Examples was evaluated by a rolling test.

[0099] More specifically, 25 mL of the composition was filled into a 50 mL cylindrical glass screw tube, and rotated in an inverted state along the side of the screw tube at a rotation speed of 45 rpm for 4 hours. After that, the composition was diluted with an appropriate solvent and the emulsified particles were observed under an optical microscope. "A": No change in the emulsified particles; "B": Enlargement of the emulsified particles was confirmed, but no obvious separation had occurred; "C": Enlargement of the emulsified particles, and further, from the appearance, obvious separation had occurred.

[0100] <Caking Resistance> The caking resistance of each of the compositions obtained in the Examples and Comparative Examples was evaluated by a sedimentation evaluation test.

[0101] More specifically, 40 g of each sample was filled into a 50 ml glass screw tube and allowed to stand at room temperature for 24 hours. After 24 hours, each sample container was repeatedly inverted, and the state of the powder that had settled to the bottom of the container was evaluated according to the following criteria: "A": When no residue was found at the bottom of the container after the first inversion, and no powder had settled; "B": When powder residue was found at the bottom of the container after the first inversion, and the residue disappeared after 1 to 10 inversions; "C": When powder residue was found at the bottom of the container after the first inversion, and the residue disappeared after 11 to 30 inversions; "D": When powder residue was found at the bottom of the container after the first inversion, and the residue did not disappear even after 50 inversions.

[0102] In the case of "A" above, no caking occurs, i.e., the caking resistance is evaluated as being the best. In addition, the caking resistance is evaluated as gradually worsening in the order from "B" to "D," and in particular, "D" is evaluated as having the worst caking resistance.

[0103] <Usability> Each of the prepared powder dispersion compositions was evaluated for usability (smoothness, absence of squeaky feeling) when applied to the skin by the following method.

[0104] Two cosmetic evaluation specialist panelists used the powder dispersion compositions and gave an overall evaluation of ease of use. The evaluation results are as follows: "A": Both smoothness and absence of squeaky feeling are very good, "B": Both smoothness and absence of squeaky feeling are good, "C": Either smoothness or absence of squeaky feeling is poor, and "D": Both smoothness and absence of squeaky feeling are good or poor.

[0105]

[0106] As is clear from Table 1, it was found that the compositions of Examples 1 to 4 all had good caking resistance of the ultraviolet scattering agent particles, were excellent in emulsion stability and usability, and further had excellent compatibility with the skin after application.

[0107] On the other hand, it was found that the compositions of Comparative Examples 1 and 2 were ineffective in terms of compatibility with the skin after application, which is thought to be because the compositions of Comparative Examples 1 and 2 did not use polyhydroxystearic acid or polyglyceryl-6 polyricinoleate as a dispersant for the ultraviolet scattering agent particles.

[0108] Furthermore, it was found that the composition of Comparative Example 3 was inferior in usability, which is believed to be because water was not blended in the composition of Comparative Example 3.

[0109]

[0110] As is clear from Table 2, the compositions of Examples 1, 5 and 6 all had good caking resistance of the ultraviolet scattering agent particles, were excellent in emulsion stability and usability, and further had excellent compatibility with the skin after application.

[0111] On the other hand, the composition of Comparative Example 4 was found to be ineffective in terms of skin compatibility after application, which is thought to be because the amount of non-polar silicone oil in the composition of Comparative Example 4 was less than 55 parts by mass per 100 parts by mass of the total oil medium.

[0112] Furthermore, it was found that the compositions of Comparative Examples 5 and 6 had poor caking resistance. This is thought to be because in the compositions of Comparative Examples 5 and 6, the content ratio of the silicone surfactant to the dispersant for the ultraviolet scattering agent particles was 1.0 or more.

[0113] Furthermore, it was found that the compositions of Comparative Examples 5 and 6 were inferior in usability. This is thought to be because the content of silicone surfactants with HLB values ​​of 8.0 or less in the compositions of Comparative Examples 5 and 6 exceeded 3.0% by mass.

[0114]

[0115] As is clear from Table 3, the compositions of Examples 1 and 7 to 10 all had good caking resistance of the ultraviolet scattering agent particles, were excellent in emulsion stability and usability, and further had excellent compatibility with the skin after application.

[0116] On the other hand, it was found that the emulsion stability (rolling) of the composition of Comparative Example 7 was poor. This is thought to be because the composition of Comparative Example 7 did not contain a silicone surfactant with an HLB value of 8.0 or less.

[0117]

[0118] As is clear from Table 4, the compositions of Examples 3 and 11 both had good caking resistance of the ultraviolet scattering agent particles, were excellent in emulsion stability and ease of use, and furthermore, were excellent in compatibility with the skin after application.

[0119] On the other hand, it was found that the composition of Comparative Example 8 had poor compatibility with the skin after application. This is thought to be because the content ratio of the ultraviolet scattering agent particles to the dispersant for the ultraviolet scattering agent particles in the composition of Comparative Example 8 was more than 10.0.

[0120] <Evaluation of Skin Compatibility After Application Using Graphics> Using the same method as in the measurement of "skin compatibility after application" described above, the absorbance from 280 nm to 400 nm was measured for the composition of Example 1 immediately after application and 20 minutes after application. The results are shown in Figure 1.

[0121] 1, it was found that the absorbance of the composition of Example 1, particularly in the UVB region (approximately 280 nm), increased significantly 20 minutes after application compared to immediately after application, and the absorbance, particularly in the visible light region (approximately 400 nm), decreased significantly. This suggests that the composition of Example 1 has the effect of blending well with the skin after application.

[0122] Example 12 In the same manner as above, a water-in-oil emulsion cosmetic composition of Example 12 was prepared and evaluated based on the formulation in Table 5. The evaluation results are shown in Table 5.

[0123]

Claims

1. A water-in-oil type emulsion cosmetic composition comprising: an oil medium; ultraviolet scattering agent particles dispersed in the oil medium; a dispersant for the ultraviolet scattering agent particles; a silicone-based surfactant having an HLB value of 8.0 or less; and water; and satisfying all of the following conditions (I) to (V): condition (I) the oil medium contains at least one of a polar oil and a polar silicone oil, and a non-polar silicone oil, or contains at least one of a polar oil and a polar silicone oil, a hydrocarbon oil, and a non-polar silicone oil, and at least a portion of the oil medium is a volatile component; condition (II) the amount of the non-polar silicone oil is 55 parts by mass or more relative to a total of 100 parts by mass of the oil medium; condition (III) the dispersant contains polyhydroxystearic acid and / or polyglyceryl polyricinoleate, and The content ratio of the ultraviolet scattering particles to the dispersant (mass of the ultraviolet scattering particles / mass of the dispersant) is 10.0 or less, condition (IV) the content of the silicone-based surfactant is 3.0 mass% or less, and condition (V) the content ratio of the silicone-based surfactant to the dispersant (mass of the silicone-based surfactant / mass of the dispersant) is less than 1.

0.

2. The composition according to claim 1, wherein said condition (I) is satisfied such that at least a portion of said non-polar silicone oil is said volatile component.

3. The composition according to claim 1 or 2, wherein said condition (II) is satisfied: the non-polar silicone oil is 55 parts by mass or more and 83 parts by mass or less, based on a total of 100 parts by mass of said oil medium.

4. The composition according to any one of claims 1 to 3, wherein said condition (I) is satisfied, when calculated excluding the volatile components of the oil medium, the amount of said non-polar silicone oil after removal of said volatile components is 40 parts by mass or less per 100 parts by mass of the oil medium after removal of said volatile components.

5. The composition according to any one of claims 1 to 4, wherein the following are satisfied: in condition (I), when calculated excluding the volatile components of the oil medium, the total of the polar oil and the polar silicone oil after removal of the volatile components is 20 parts by mass or more per 100 parts by mass of the oil medium after removal of the volatile components, the hydrocarbon oil after removal of the volatile components is 70 parts by mass or less per 100 parts by mass of the oil medium after removal of the volatile components, and the non-polar silicone oil after removal of the volatile components is 40 parts by mass or less per 100 parts by mass of the oil medium after removal of the volatile components; and in condition (II), the total of the polar oil and the polar silicone oil is 10 parts by mass or more per 100 parts by mass of the oil medium, and the hydrocarbon oil is 20 parts by mass or less per 100 parts by mass of the oil medium.

6. The composition according to any one of claims 1 to 5, wherein said condition (I) is satisfied, when calculated excluding the volatile components of the oil medium, the amount of said dispersant is 1.0 part by mass or more and 30 parts by mass or less per 100 parts by mass of the oil medium after excluding the volatile components and said dispersant in total.

7. The composition according to any one of claims 1 to 6, wherein the ultraviolet scattering agent particles are present in an amount of 10 parts by mass or more per 100 parts by mass of the oil medium in total.

8. The composition according to any one of claims 1 to 7, wherein the ultraviolet scattering particles are at least one selected from the group consisting of titanium oxide, zinc oxide, iron oxide, and cerium oxide.

9. The composition according to any one of claims 1 to 8, wherein the non-polar silicone oil comprises a linear non-polar silicone oil.

10. The composition according to any one of claims 1 to 9, wherein the non-polar silicone oil comprises dimethicone.

11. The composition of claim 10, wherein the polar silicone oil comprises a methylphenylpolysiloxane.

12. The composition according to any one of claims 1 to 10, wherein the polar oil does not contain an ultraviolet light absorber.

13. The composition according to any one of claims 1 to 12, wherein the water content is less than 30% by mass.

14. The composition according to any one of claims 1 to 13, which is a sunscreen cosmetic composition.

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