Water-in-oil composition

Abstract

Provided is a water-in-oil composition comprising: (A) an organically modified clay mineral, (B) a polar oil having an IOB of 0.3 or more in an amount of 3% by mass or more, (C) a nonpolar oil having an alkyl side chain, (D1) a polyoxyethylene hardened castor oil, and (D2) an emulsification activator which is a compound having an alkyl side chain having 10 or more carbons, or a compound having a fatty acid side chain having 10 or more carbons or a polyoxyethylene adduct thereof.

Description

Technical Field

[0001] This invention relates to water-in-oil compositions. Background Technology

[0002] Water-in-oil compositions, which use oil-based components as the external phase and water-based components as the internal phase, exhibit excellent moisturizing and occlusive properties when applied to the skin, and are therefore widely used as cosmetics and quasi-pharmaceuticals. For water-in-oil compositions to function properly, maintaining a stable emulsion state between the oil and water components is crucial, and various methods for stabilization have been investigated.

[0003] For example, as described in Patent Document 1, organically modified clay minerals are known to be used as emulsifying aids. By appropriately combining and using organically modified clay minerals with surfactants, the composition can be made into a stable gel.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2013-107865 Summary of the Invention

[0007] The problem that the invention aims to solve

[0008] Water-in-oil compositions are often used as skin application agents (cosmetics, personal care products, etc.) with UV protection functions. In such cases, the formulation contains polar oils with high UV absorption. However, if the content of polar oil is increased, it becomes difficult to stably maintain the emulsion state of the oil and water components, and the use of organically modified clay minerals results in a gel-like texture.

[0009] In view of the above, one objective of the present invention is to improve the stability of the properties of water-in-oil compositions containing polar oils.

[0010] Methods for solving problems

[0011] One aspect of the present invention for solving the above-mentioned problems is a water-in-oil composition comprising: (A) an organically modified clay mineral, (B) a polar oil with an IOB of 0.3 or more at 3% by mass, (C) a nonpolar oil having an alkyl side chain, (D1) a polyoxyethylene-cured castor oil, and (D2) an emulsifying agent, which is a compound having an alkyl side chain having 10 or more carbon atoms, or a compound having a fatty acid side chain having 10 or more carbon atoms, or a polyoxyethylene adduct thereof.

[0012] The effects of the invention

[0013] According to one aspect of the present invention, the stability of the properties of water-in-oil compositions containing polar oils can be improved. Detailed Implementation

[0014] The embodiments of the present invention will be described in detail below, but the present invention is not limited to the following embodiments.

[0015] <Water-in-oil composition>

[0016] The water-in-oil composition of the first embodiment of the present invention contains: (A) an organically modified clay mineral, (B) a polar oil with an IOB of 0.3 or more at 3% by mass, (C) a nonpolar oil having an alkyl side chain, (D1) a polyoxyethylene-cured castor oil, and (D2) an emulsifying agent, which is a compound having an alkyl side chain having 10 or more carbon atoms, or a compound having a fatty acid side chain having 10 or more carbon atoms, or a polyoxyethylene adduct thereof.

[0017] Furthermore, the water-in-oil composition of the second embodiment of the present invention contains (A) an organically modified clay mineral, (B) a polar oil with an IOB of 0.3 or more at 3% by mass, (C) a nonpolar oil having an alkyl side chain, and (D) a fatty acid ester of polyoxyethylene cured castor oil.

[0018] The water-in-oil compositions of the present invention are solid or semi-solid and can be provided in a state referred to as gel, colloidal, paste, or ointment. Such water-in-oil compositions are easy to apply as skin coatings and can form a film of a certain thickness on the skin surface, thus providing high protection and occlusion of the skin.

[0019] [First Implementation]

[0020] <(A) Organically Modified Clay Minerals>

[0021] (A) Organically modified clay minerals are not particularly limited to compounds commonly used in skin ointments. (A) Organically modified clay minerals can be, for example, cationic modified clay minerals obtained by treating layered clay minerals such as bentonite, synthetic lithium saponite, lithium montmorillonite, montmorillonite, and magnesium aluminum silicate with quaternary ammonium salt-type cationic surfactants. Specific examples of (A) organically modified clay minerals include dimethyl distearate ammonium lithium montmorillonite (distearate diammonium lithium montmorillonite), dimethyl alkyl ammonium lithium montmorillonite, benzyl dimethyl stearyl ammonium lithium montmorillonite, and magnesium aluminum silicate treated with distearate dimethyl ammonium chloride. Commercially available examples include benton 27 (benzyl dimethyl stearyl ammonium chloride treated lithium montmorillonite: manufactured by National Red and Reox), benton 34 (chemical name: quaternium-18 bentonite: manufactured by Reox), benton 38 (distearyl dimethyl ammonium chloride treated lithium montmorillonite: manufactured by National Red), benton 38V (quaternium-18 lithium montmorillonite: manufactured by Reox), clay tone 40 (manufactured by Southern Clay), and clay tone SO (manufactured by Southern Clay). Among these, dimethyl distearyl ammonium lithium montmorillonite and benzyl dimethyl stearyl ammonium lithium montmorillonite are preferred, and dimethyl distearyl ammonium lithium montmorillonite is more preferred. These (A) organic modified clay minerals can be used alone or in combination of two or more.

[0022] (A) Organically modified clay minerals can act as emulsifying aids in the emulsification of oil-based and water-based components. More specifically, by adding (A) organically modified clay minerals, the oil-based components can be effectively thickened or gelled, and the gelled state of the oil phase can be maintained over time. Therefore, the dispersion state of the aqueous phase is also stable, and the entire water-in-oil composition can be stably maintained in a solid or semi-solid state, or a gelled state, for a long time.

[0023] The content of (A) organic modified clay mineral is preferably 0.05% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more and 5% by mass or less, relative to the total amount of the water-in-oil composition. By making the content of (A) organic modified clay mineral 0.05% by mass or more, sufficient property stability can be imparted to the water-in-oil composition. Furthermore, by making the content 10% by mass or less, a good user experience with less stickiness is obtained, and the elongation on the skin is also reduced, thus improving usability.

[0024] <(B) Polar Oils>

[0025] (B) The polar oil can be a highly polar oily component commonly used in skin ointments. The IOB value of the (B) polar oil used in this manner can be 0.3 or higher. Furthermore, the IOB value of the (B) polar oil is preferably 0.8 or lower, more preferably 0.7 or lower. When the (B) polar oil contains a UV absorber (described later), the IOB value of the UV absorber is preferably 0.3 or higher and 0.7 or lower. By ensuring that the IOB value of the (B) polar oil is 0.3 or higher, the gel-like properties of the water-in-oil composition can be stabilized, and this stable state can be maintained over time.

[0026] The IOB value is short for Inorganic / Organic Balance, representing the ratio of inorganic to organic content, and is an indicator of the degree of polarity of an organic compound. Specifically, the IOB value is expressed by the formula: "IOB value = Inorganic value / Organic value". The "inorganic value" and "organic value" are determined, for example, such that for one carbon atom in the molecule, the "organic value" is 20, and for one hydroxyl group, the "inorganic value" is 100, depending on the various atoms or functional groups. By accumulating the "inorganic value" and "organic value" of all atoms and functional groups in an organic compound, the IOB value of that compound can be calculated (e.g., Fujita, see "Chemistry Field", Vol. 11, No. 10, pp. 719-725, 1957). There is a tendency for a higher IOB value to indicate higher inorganic content and higher hydrophilicity. When polar oil (B) is formed by two or more combinations with different IOB values, the IOB value of polar oil (B) becomes the weighted average value.

[0027] The content of polar oil (B) relative to the total amount of the water-in-oil composition can be 3% by mass or more. Furthermore, depending on the function or application of the composition, the content of polar oil (B) relative to the total amount of the composition is preferably 5% by mass or more, more preferably 7% by mass or more. By setting the lower limit of the content of polar oil (B) to the above values, moisturizing effects or occlusion effects can be improved. Furthermore, according to the composition of this embodiment, even when containing a relatively high content of polar oil (B), the water-in-oil emulsion state of the composition can be stabilized, as described above.

[0028] (B) The content of polar oil can be, relatively speaking, 30% by mass or less, more preferably 20% by mass or less. By setting the upper limit of the content of polar oil (B) to the above value, the stability of the formulation can be improved and the stickiness during coating can be suppressed, resulting in a better user experience.

[0029] (B) The polar oil preferably contains a UV absorber, i.e., a polar oil with UV absorption function. When the polar oil in (B) contains a UV absorber, the water-in-oil composition of this method is suitable for use as a cosmetic composition with sun protection properties, or as a sunscreen composition.

[0030] (B) The type of ultraviolet absorber contained in the polar oil is not particularly limited, and may be benzoic acid derivatives, salicylic acid derivatives, cinnamic acid derivatives, dibenzoylmethane derivatives, β,β-diphenylacrylate derivatives, benzophenone derivatives, benzyl camphor derivatives, phenylbenzimidazole derivatives, triazine derivatives, phenylbenzotriazole derivatives, anthraquinone derivatives, imidazoline derivatives, benzomalon derivatives, 4,4-diarylbutadiene derivatives, etc. Specific examples include octyl salicylate (IOB = 0.6), octocrylene (IOB = 0.32), homolsalate (IOB = 0.6), ethylhexyl methoxycinnamate (IOB = 0.35), etc., preferably octyl salicylate (IOB = 0.6), octocrylene (IOB = 0.32), and homolsalate (IOB = 0.6). One of the above ultraviolet absorbers may be used alone, or two or more may be used in combination.

[0031] The content of ultraviolet absorber can be 100% by mass relative to the total amount of polar oil (B), that is, the polar oil (B) in the water-in-oil composition of this method can be an ultraviolet absorber.

[0032] Furthermore, the content of the ultraviolet absorber is preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 7% by mass or more, relative to the total amount of the water-in-oil composition. Additionally, the content of the ultraviolet-absorbing polar oil is preferably 20% by mass or less, relative to the total amount of the water-in-oil composition. By setting the content of the ultraviolet absorber within the above range, it is possible to provide a water-in-oil composition that has ultraviolet protection function and stable properties.

[0033] Specific examples of ester oils include diisopropyl sebacate (IOB = 0.4), triethylhexanoate (triethylhexanoate) (IOB = 0.35), tripropylene glycol dinepentanoate (IOB = 0.52), pentaerythritol tetraethylhexanoate (IOB = 0.35), diethylhexyl succinate (IOB = 0.32), neopentyl glycol diethylhexanoate (IOB = 0.32), trimethylolpropane triethylhexanoate (IOB = 0.33), pentaerythritol tetraethylhexanoate (IOB = 0.35), and diisopropyl adipate (IOB = 0.35). The preferred esters include diisostearyl malate (IOB = 0.46), tripropylene glycol di-2-ethylhexanoate (IOB = 0.52), propylene glycol dioctanoate (IOB = 0.32), and glyceryl triethylhexanoate (IOB = 0.36), among which diisopropyl lindenate (IOB = 0.4), glyceryl tri-2-ethylhexanoate (IOB = 0.35), tripropylene glycol di-2-ethylhexanoate (IOB = 0.52), pentaerythritol tetra-2-ethylhexanoate (IOB = 0.35), and diethylhexyl succinate (IOB = 0.32). These ester oils can be used alone or in combination of two or more.

[0034] Water-in-oil compositions, by containing ester oil, can adjust the emulsification balance between oil-based and water-based components, thereby promoting the dissolution of ultraviolet absorbers.

[0035] Furthermore, as clarified by the specific example of polar oil (B) above, polar oil (B) can be either solid or liquid at room temperature.

[0036] <(C) Non-polar oil>

[0037] (C) Non-polar oil refers to an oil-based component with relatively low polarity, such as an oil-based component with an IOB of less than 0.3. Examples of (C) non-polar oils include hydrocarbon oils, non-polar silicone oils, and non-polar ester oils. In this embodiment, the non-polar oil preferably has a structure with alkyl side chains. Here, "side chain" refers to a chain-like portion directly bonded to the main chain of the longest linear portion of the chain molecule. By incorporating a (C) non-polar oil with alkyl side chains, the gel-like properties of the water-in-oil composition can be stabilized for a long time.

[0038] (C) The non-polar oil can be a monomer or a polymer (including oligomers). (C) The non-polar oil can be in both monomer and polymer form, and the number of carbon atoms in one alkyl side chain can be 1, preferably 2 or more, more preferably 3 or more, and even more preferably 5 or more. Furthermore, the alkyl group in the alkyl side chain can be a straight-chain or branched alkyl group.

[0039] When (C) the nonpolar oil is a monomer, the number of alkyl side chains bonded to the nonpolar oil in one molecule can be 1, preferably 2 or more, more preferably 3 or more, and even more preferably 5 or more. When (C) the nonpolar oil is a polymer, the number of alkyl side chains in one monomer unit can be 1 or 2 or more.

[0040] Furthermore, when (C) the non-polar oil is a monomer, the total number of carbons contained in the alkyl side chains of one molecule (or the total number of carbons contained in all alkyl side chains when there are two or more alkyl side chains) can be 1, preferably 2 or more, more preferably 3 or more, and preferably 10 or less, more preferably 8 or less. When (C) the non-polar oil is a polymer, the total number of carbons contained in the alkyl side chains of one monomer unit can be 1, preferably 2 or more, more preferably 3 or more, more preferably 5 or more, and preferably 20 or less, more preferably 10 or less.

[0041] In the case where (C) is a non-polar oil that is a hydrocarbon oil with alkyl side chains, it can be an aliphatic unsaturated hydrocarbon oil that is liquid or solid at room temperature.

[0042] Specific examples of hydrocarbon oils having alkyl side chains include hydrogenated polydecene, hydrogenated polyisobutylene, squalane, isohexadecane, and isodecane. Among these, cured polydecene is preferred. These hydrocarbon oils can be used alone or in combination of two or more.

[0043] Examples of nonpolar organosilicones with alkyl side chains include chain polysiloxanes, such as dimethyl polysiloxanes, which are organosilicon compounds with alkyl side chains. Functional groups other than alkyl groups can be introduced, and the functional group introduced as the side chain is preferably only alkyl. Furthermore, organosilicones without aromatic functional groups are preferred.

[0044] Octyl polymethylsiloxane is a specific example of a nonpolar organosilicon with alkyl side chains. These silicone oils can be used alone or in combination of two or more.

[0045] In the case where (C) is a non-polar oil, a specific example of a non-polar oil is cetyl 2-ethylhexanoate.

[0046] (C) The content of the non-polar oil can be, relative to the total amount of the water-in-oil composition, preferably 5% by mass or more and 40% by mass or less, more preferably 10% by mass or more and 30% by mass or less. By keeping the content of the non-polar oil (C) within the above range, the gel-like properties of the water-in-oil composition can be stabilized for a long time, and the feel during coating can also be improved.

[0047] Furthermore, the ratio of the content of (C) non-polar oil to the content of (B) polar oil ([content of (C) non-polar oil] / [content of (B) polar oil)]) is preferably 0.25 to 4 or less, more preferably 0.3 to 3.5 or less, and even more preferably 0.4 to 3.0 or less. By making the ratio of the content of (C) non-polar oil to the content of (B) polar oil within the above range, the balance between (C) non-polar oil and (B) polar oil becomes good, the oil phase can be stably gelled, and the gelation state of the water-in-oil composition is well maintained.

[0048] <(D1) Polyoxyethylene Cured Castor Oil>

[0049] (D1) Polyoxyethylene (POE) cured castor oil (polyoxyethylene hydrogenated castor oil) is a product of adding hydrogen and polyethylene glycol (PEG) to castor oil. (D1) Polyoxyethylene cured castor oil can act as a nonionic surfactant. The water-in-oil composition of this method is mainly a highly functional substance that disperses (A) organic modified clay minerals in the oil phase.

[0050] The HLB value of the (D1) polyoxyethylene cured castor oil used in this manner is not particularly limited. However, in order to maintain the water-in-oil emulsion state well, a value of 12 or less is preferred. In addition, "HLB value" is the HLB (Hydrophilic-Lipophilic Balance) value that represents the degree of affinity of the surfactant in water and oil, and can be calculated using Griffin's formula (HLB value = molecular weight of glycerol fraction × 20 / total molecular weight).

[0051] The molar number of polyoxyethylene added to (D1) polyoxyethylene-cured castor oil is preferably 1 to 60, more preferably 5 to 40.

[0052] Specific examples of (D1) polyoxyethylene cured castor oil include POE(5) cured castor oil, POE(10) cured castor oil, POE(20) cured castor oil, POE(30) cured castor oil, POE(40) cured castor oil, POE(60) cured castor oil, etc., among which POE(10) cured castor oil is preferred.

[0053] The aforementioned (D1) polyoxyethylene cured castor oil can be used alone or in combination of two or more types.

[0054] The content of (D1) polyoxyethylene-cured castor oil relative to the total amount of the water-in-oil composition is preferably 0.05% to 10% by mass, more preferably 0.1% to 5% by mass. By setting the content of (D1) polyoxyethylene-cured castor oil within the above range, the gelation or thickening effect of (A) organic modified clay minerals can be promoted, and the gel-like properties of the water-in-oil composition can be stably maintained.

[0055] Furthermore, the ratio of the content of (D1) polyoxyethylene-cured castor oil to the content of (A) organic modified clay mineral ([content of (D1) polyoxyethylene-cured castor oil] / [content of (A) organic modified clay mineral]) is preferably 0.1 to 5, more preferably 0.5 to 2. By setting the ratio of the content of (D1) polyoxyethylene-cured castor oil to the content of (A) organic modified clay mineral within the above range, the gelation of the oil-based components is promoted, thereby making it easier to maintain the overall properties of the water-in-oil composition in a gel state.

[0056] <(D2) Emulsifier>

[0057] Furthermore, in the water-in-oil composition of this method, the (D2) emulsifying agent comprises a compound having an alkyl side chain with 10 or more carbon atoms, or a compound having a fatty acid side chain with 10 or more carbon atoms, or a polyoxyethylene adduct thereof. The (D2) emulsifying agent primarily promotes the emulsification of oil-based and water-based components, and has a high function of maintaining the emulsion state over time.

[0058] (D2) More specifically, the emulsifying surfactant can be an organosilicon-based emulsifying surfactant having alkyl side chains with 10 or more carbon atoms. The alkyl group in the alkyl side chain can be a straight-chain or branched alkyl group. In addition to the alkyl side chain, the organosilicon-based emulsifying surfactant can have polyether side chains (functional group side chains derived from polyethylene glycol or polypropylene glycol), and further can have organosilicon side chains.

[0059] When the (D2) emulsifying surfactant is an organosilicon-based emulsifying surfactant, the number of carbon atoms in one alkyl side chain is preferably 10 to 20, more preferably 12 to 15. Furthermore, the alkyl group in the alkyl side chain can be either straight-chain or branched.

[0060] Specific examples of organosilicon-based emulsifying agents include cetyl PEG / PPG-10 / 1 polydimethylsiloxane and lauryl PEG-9 polydimethylsiloxyethyl polydimethylsiloxane.

[0061] Furthermore, the (D2) emulsifying agent can be a fatty acid ester of glycerol or polyglycerol having a fatty acid side chain with 10 or more carbon atoms, or a polyoxyethylene adduct thereof. In this specification, the fatty acid side chain is a functional group derived from fatty acids or fatty acid condensates, and more specifically, it can be a functional group that has removed a hydrogen atom from the carboxyl group of a fatty acid, or a functional group that has removed a hydrogen atom from the terminal carboxyl group of a condensate of unsaturated fatty acids or hydroxy fatty acids.

[0062] When the fatty acid side chain originates from a fatty acid monomolecule, the number of carbon atoms in the fatty acid is preferably 10 to 24, more preferably 14 to 22, and even more preferably 16 to 20. Furthermore, when the fatty acid side chain originates from a fatty acid condensate, the number of carbon atoms in the fatty acid (before condensation) is 10 to 24, more preferably 14 to 22, and even more preferably 16 to 20.

[0063] When the (D2) emulsifying agent is a polyoxyethylene adduct, the molar number of polyoxyethylene is preferably 5 or more and 60 or less, more preferably 10 or more and 40 or less.

[0064] Furthermore, when the (D2) emulsifying surfactant is a polyoxyethylene adduct, it is possible to add polyoxyethylene to the fatty acid side chain itself, thus eliminating the presence of polyethylene glycol chains branched from the fatty acid side chain. Alternatively, it is possible to make the fatty acids constituting the fatty acid side chain unsubstituted fatty acids, more specifically, fatty acids without hydroxyl groups.

[0065] In the case where the (D2) emulsifying agent is a fatty acid ester of glycerol or polyglycerol having a fatty acid side chain with 10 or more carbon atoms, or a polyoxyethylene adduct thereof, examples include polyoxyethylene adducts of fatty acid triglycerides, such as POE(10) triisostearate glycerol, POE(15) triisostearate glycerol; fatty acid esters of polyglycerol, such as polyglycerol pentaoleate-10, polyglycerol triisostearate-2, polyglycerol pentastearate-10; condensates of hydroxy fatty acids and esters of polyglycerol, such as polyglycerol ricinoleate-6, polyglycerol hydroxystearate-6.

[0066] In addition, the HLB value of the (D2) emulsifying surfactant is preferably 9 or less, more preferably 7.5 or less, and even more preferably 6 or less.

[0067] (D2) The emulsifying surfactant can be a compound having alkyl side chains with 10 or more carbon atoms, a compound having fatty acid side chains with 10 or more carbon atoms, or a polyoxyethylene adduct thereof. The content of (D2) emulsifying surfactant relative to the total amount of the water-in-oil composition is preferably 0.05% by mass to 10% by mass, more preferably 0.1% by mass to 5% by mass. By containing (D2) emulsifying surfactant within the above range, the emulsified state of the oil-based components and the water-based components can be maintained well for a long time.

[0068] <Other ingredients>

[0069] In this type of water-in-oil composition, in addition to the components (A) to (D2) mentioned above, water, which is commonly used in external compositions, is contained. The water can be purified water, ion-exchanged water, tap water, etc. The water content in this type of composition is preferably 50% by mass or more and 80% by mass or less relative to the total amount of the water-in-oil composition, more preferably 55% by mass or more and 75% by mass or less.

[0070] Furthermore, the water-in-oil composition may contain the aforementioned components (A) to (D2) and any other components besides water, within a range that does not impair the effects of this method. For example, as an aqueous component, it may contain water-soluble alcohols, etc., and as an oil-based component, it may contain higher alcohols, liquid fats, solid fats, waxes, higher fatty acids, fragrances, etc.

[0071] Furthermore, the water-in-oil composition of this method may contain wax. Wax is an oil-based component that is solid or semi-solid at room temperature, containing hydrocarbons, neutral fats, higher fatty acids, esters of higher fatty acids and higher alcohols, and can improve the dosage form stability of the composition. From the viewpoint that the obtained water-in-oil composition has a lighter feel when used, a small amount of wax is preferable, preferably less than 1% by mass relative to the total amount of the water-in-oil composition, more preferably less than 0.5% by mass, and even more preferably less than 0.1% by mass. Furthermore, from the viewpoint that heating during manufacturing can be omitted, a wax content of 0% by mass is preferred, that is, the water-in-oil composition does not contain wax. Alternatively, the water-in-oil composition of this method can form a stable gel through the combination of the above components (A), (B), (C), (D1), and (D2), thereby obtaining a stable water-in-oil composition even without the addition of wax.

[0072] Furthermore, the water-in-oil composition of this method may contain cyclic organosilicones or cyclic polysiloxanes (e.g., octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecylcyclohexasiloxane, etc.). However, when cyclic organosilicones are contained, their content relative to the total amount of the water-in-oil composition is preferably 1% by mass or less, more preferably 0.5% by mass or less, even more preferably 0.1% by mass or less, and even more preferably 0.01% by mass or less. Moreover, the water-in-oil composition preferably does not contain cyclic organosilicones, or does not contain any at all. In this specification, "substantially does not contain" or "substantially does not contain" refers to a manner in which the specified component is unavoidably incorporated during the acquisition of the raw materials or the manufacturing process of the composition.

[0073] In addition, it may contain cationic surfactants, anionic surfactants, nonionic surfactants other than those mentioned above, amphoteric surfactants, and other surfactants. Furthermore, it may contain thickeners, humectants, transdermal absorption inhibitors, chelating agents, pigments, antioxidants, preservatives, anti-inflammatory agents, whitening agents, plant extracts, activators, blood circulation promoters, and anti-seborrheic agents.

[0074] Furthermore, the water-in-oil composition of this method can contain organic or inorganic powders. Specific examples of inorganic powders include titanium dioxide, zinc oxide, cerium oxide, talc, silica, mica, sericite, kaolin, titanium mica, iron oxide black, iron oxide yellow, iron oxide red, ultramarine, navy blue, chromium oxide, and chromium hydroxide. Additionally, it can be a composite powder in which particles other than titanium dioxide are coated with titanium dioxide. Furthermore, it can contain powders of biodegradable resins such as polyhydroxybutyric acid (PHBEA) and poly(3-hydroxybutyric acid-co-3-hydroxyvalerate) (with an average particle size of 1 μm to 20 μm).

[0075] <Uses>

[0076] The uses of the water-in-oil composition of this method are not particularly limited. In the fields of cosmetics, quasi-pharmaceuticals, and personal care products, it is particularly suitable as a cosmetic agent or skin application agent. In addition, the water-oil composition of this method can be used as sunscreen (sunscreen cream) for the purpose of ultraviolet protection, or as a cosmetic agent that enhances ultraviolet protection, such as basic cosmetic agents such as foundation or makeup cosmetics.

[0077] [Second Implementation]

[0078] The composition of the second embodiment contains the same (A) organically modified clay minerals, (B) at least 3% by mass of a polar oil with an IOB of 0.3 or more, and (C) a non-polar oil having alkyl side chains as in the first embodiment. However, instead of (D1) polyoxyethylene-cured castor oil and (D2) emulsifying activator in the first embodiment, it contains fatty acid esters of (D) polyoxyethylene-cured castor oil. By containing fatty acid esters of (D) polyoxyethylene-cured castor oil, it is possible to promote the uniform dispersion of (A) organically modified clay minerals in the oil components and to maintain a good emulsification balance between the oil and water components in the water-in-oil composition, thereby enabling long-term stabilization of the properties of the water-in-oil composition.

[0079] The fatty acids constituting the fatty acid esters of (D) polyoxyethylene cured castor oil can be higher fatty acids, preferably with 13 to 25 carbon atoms, more preferably 16 to 20. Furthermore, the fatty acid can have a straight-chain or branched structure, preferably a branched fatty acid, and particularly preferably isostearic acid.

[0080] The number of moles of the fatty acid ester of (D) polyoxyethylene-cured castor oil is preferably 5 to 60, more preferably 10 to 40.

[0081] As specific examples of fatty acid esters of (D) polyoxyethylene cured castor oil, examples include polyoxyethylene adducts of triisostearic acid such as castor oil cured with PEG-10 triisostearic acid and castor oil cured with PEG-20 triisostearic acid.

[0082] (D) The content of fatty acid esters in polyoxyethylene cured castor oil relative to the total amount of the water-in-oil composition is preferably 0.1% to 15% by mass, more preferably 1% to 10% by mass. By containing it within the above range, the emulsion state of the oil-based components and the water-based components can be well maintained for a long time.

[0083] Furthermore, the ratio of the fatty acid ester content of (D) polyoxyethylene-cured castor oil to the content of (A) organically modified clay mineral ([content of (D) polyoxyethylene-cured castor oil] / [content of (A) organically modified clay mineral]) is preferably 0.2 to 10 or less, more preferably 1 to 5 or less. By setting the ratio of the content of (D) polyoxyethylene-cured castor oil to the content of (A) organically modified clay mineral within the above range, the gelation of the oil-based components is promoted, the emulsification state of the oil-based components and the water-based components becomes good, and the overall properties of the water-in-oil composition are easily maintained in a gel state.

[0084] In the water-in-oil composition of the second embodiment, the other compatible components and the uses of the composition are the same as those described in the first embodiment.

[0085] Example

[0086] The compositions shown in Tables 1 and 2 were prepared using conventional methods. Specifically, polar oil, non-polar oil, polyoxyethylene-cured castor oil, and an emulsifying agent were mixed, followed by the addition of an organically modified clay mineral. After further mixing, water was added to obtain the compositions of Examples 1-11 and Comparative Examples 1-5. Similarly, polar oil, non-polar oil, and fatty acid esters of polyoxyethylene-cured castor oil were mixed, followed by the addition of an organically modified clay mineral. After further mixing, water was added to obtain the composition of Example 12. The gelation state of Examples 1-12 and Comparative Examples 1-5 was evaluated. Tables 1 and 2 show the evaluation results.

[0087] <Evaluation of gelation stability>

[0088] The gelation stability of the compositions in each example was evaluated. This evaluation was performed visually according to the following evaluation criteria: A: It was confirmed that the composition formed a good gel and maintained stability even after 28 days.

[0089] B: It can be confirmed to form a good gel and maintain stability even after 7 days.

[0090] C: It can be confirmed to form a good gel and maintain stability even after 1 day.

[0091] D: It did not become a gel.

[0092] [Table 1]

[0093]

[0094] [Table 2]

[0095]

[0096] The following are specific formulation examples (Formulation Examples 1 to 4) of the water-in-oil composition of this method.

[0097] [Table 3]

[0098] (Prescription Example 1: Makeup Base)

[0099] Hydrogenated bis(decene) 10 Hydrogenated polydecene 5 Isododecane 5 Isohexadecane 5 Ethylhexyl salicylate 5 Octylene 5 Distearate dimethylammonium chloride 0.1 Palmitic acid 0.05 PEG-10 hydrogenated castor oil 2 Lauryl PEG-9 polydimethylsiloxane-ethyl dimethylsiloxane 2 Distearate diammonium lithium montmorillonite 2 Fatty acid-treated titanium dioxide 5 Silicon-treated zinc oxide 12 Silicon-treated silica 6 Ester-amino acid treated pigment-grade titanium dioxide 4 Ester-amino acid treated iron oxide yellow 1.2 Ester-amino acid treated iron oxide red 0.2 Ester-amino acid treated iron oxide black 0.05 water 22.5 Hibiscus flower extract 0.1 Hydrolyzed silk 0.1 Wild thyme extract 0.1 Glycyrrhizic acid 2K 0.1 Acetate tocopherol 0.1 Acacia extract 0.1 Ginseng root extract 0.1 Saxifraga extract 0.1 Bupleurum root extract from Mishima 0.1 2-O-ethyl ascorbic acid 0.1 Scutellaria baicalensis root extract 0.1 Mangosteen bark extract 0.1 ethanol 2 Phenoxyethanol 0.5 EDTA-3Na 0.2 glycerin 4 Total (by mass%) 100

[0100] [Table 4]

[0101] (Prescription Example 2: BB Cream)

[0102] PEG-10 dimethylsiloxane 3.5 Lauryl PEG-9 polydimethylsiloxane-ethyl dimethylsiloxane 2 PEG-10 hydrogenated castor oil 2 Ethylhexyl salicylate 10 Isohexadecane 10 Hydrogenated bis(decene) 20 Distearate diammonium lithium montmorillonite 2 Fatty acid-treated titanium dioxide 4.5 silicon dioxide 5 Silicate-treated pigment-grade titanium dioxide 4.4 Silicic acid treated iron oxide red 0.348 Silicic acid treated iron oxide yellow 0.756 Silicate-treated iron oxide black 0.0125 water 20.2835 EDTA-3Na 0.2 Xylitol 1 Trehalose 1 glycerin 2.5 DPG 7 BG 2 ethanol 1 Phenoxyethanol 0.5 Total (by mass%) 100

[0103] [Table 5]

[0104] (Prescription Example 3: Sunscreen)

[0105] Hydrogenated bis(decene) 10 Hydrogenated polydecene 5 Isododecane 5 Isohexadecane 5 Ethylhexyl salicylate 5 Octylene 5 diisopropyl sebacate 5 PEG-10 hydrogenated castor oil 2 Lauryl PEG-9 polydimethylsiloxane-ethyl dimethylsiloxane 2 Distearate diammonium lithium montmorillonite 2 Hydrophobicated titanium dioxide 5 Hydrophobicated zinc oxide 12 Hydrophobic treatment of silica 6 Polyhydroxybutyric acid 0.1 Poly(3-hydroxybutyric acid-co-3-hydroxyvalerate) 0.1 water 24.1 ethanol 2 Phenoxyethanol 0.5 EDTA-3Na 0.2 glycerin 4 Total (by mass%) 100

[0106] [Table 6]

[0107] (Prescription Example 4: BB Cream)

[0108] PEG-10 dimethylsiloxane 3.5 Lauryl PEG-9 polydimethylsiloxane-ethyl dimethylsiloxane 2 PEG-10 hydrogenated castor oil 2 Ethylhexyl salicylate 10 Isohexadecane 10 Hydrogenated bis(decene) 20 Distearate diammonium lithium montmorillonite 2 Fatty acid-treated titanium dioxide 4.5 silicon dioxide 5 Silicate-treated pigment-grade titanium dioxide 4.4 Silicic acid treated iron oxide red 0.348 Silicic acid treated iron oxide yellow 0.756 Silicate-treated iron oxide black 0.0125 water 15.2835 EDTA-3Na 0.2 Niacinamide 5 Xylitol 1 Trehalose 1 glycerin 2.5 DPG 7 BG 2 ethanol 1 Phenoxyethanol 0.5 Total (by mass%) 100

[0109] This application claims priority based on Japanese Patent Application No. 2021-022875, filed on February 16, 2021, the entire contents of which are incorporated herein by reference.

Claims

1. A water-in-oil composition comprising: (A) Organically modified clay mineral, wherein (A) organically modified clay mineral is distearate-based diammonium lithium montmorillonite. (B) Polar oils with an IOB of 0.3 or higher, accounting for 3% or more by mass. (C) Non-polar oil, which is one or more of a non-polar silicone oil having 2 to 20 carbon side chains and a non-polar hydrocarbon oil having alkyl side chains. (D1) Polyoxyethylene hydrogenated castor oil, wherein the (D1) polyoxyethylene hydrogenated castor oil is selected from either PEG-10 hydrogenated castor oil or PEG-40 hydrogenated castor oil, and (D2) Emulsifying surfactant, which is an organosilicon with alkyl side chains having 10 to 20 carbon atoms, or The fatty acid ester of glycerol or polyglycerol, or its polyoxyethylene adduct, having a fatty acid side chain with 10 to 24 carbon atoms, wherein the fatty acid side chain is a group derived from fatty acids or a group derived from a condensation of unsaturated fatty acids or hydroxy fatty acids, and the (D2) emulsifying agent is selected from any one of lauryl PEG-9 polydimethylsiloxane, polyglycerol polyricinoleate-6, and hexadecyl dimethylsiloxane.

2. The water-in-oil composition according to claim 1, The ratio of the content of (D1) polyoxyethylene hydrogenated castor oil to the content of (A) organic modified clay mineral is 0.1 to 5.

3. The water-in-oil composition according to claim 1 or 2, The average molar number of ethylene oxide addition in the (D1) polyoxyethylene hydrogenated castor oil is 5 to 60.

4. A water-in-oil composition comprising: (A) Organically modified clay mineral, wherein (A) organically modified clay mineral is distearate-based diammonium lithium montmorillonite. (B) Polar oils with an IOB of 0.3 or higher, accounting for 3% or more by mass. (C) Non-polar oil, which is one or more of a non-polar silicone oil having alkyl side chains with 2 to 20 carbon atoms and a non-polar hydrocarbon oil having alkyl side chains with 2 to 20 carbon atoms, and (D) Fatty acid esters of polyoxyethylene hydrogenated castor oil, wherein the fatty acid esters of (D) polyoxyethylene hydrogenated castor oil are triisostearic acid PEG-10 hydrogenated castor oil. The wax content is less than 0.1% by mass.

5. The water-in-oil composition according to claim 4, The ratio of the fatty acid ester content of the (D) polyoxyethylene hydrogenated castor oil to the content of the (A) organic modified clay mineral is 0.2 to 10.

6. The water-in-oil composition according to claim 4, The average molar number of ethylene oxide additions to the fatty acid esters of the (D) polyoxyethylene hydrogenated castor oil is 5 to 60.

7. The water-in-oil composition according to any one of claims 1, 2, and 4, The polar oil (B) contains a UV absorber.

8. The water-in-oil composition according to any one of claims 1, 2, and 4, The (C) non-polar oil is selected from one or more of the group consisting of hydrogenated polydecene, octyl polymethylsiloxane, and squalane.

9. The water-in-oil composition according to claim 8, The non-polar oil (C) is hydrogenated polydecene.

10. The water-in-oil composition according to any one of claims 1, 2, and 4, The ratio of the content of the non-polar oil in (C) to the content of the polar oil in (B) is 0.25 to 4.

11. The water-in-oil composition according to any one of claims 1, 2, and 4, The content of cyclic organosilicon is less than 1% by mass.

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