Surface-coated inorganic particles

Abstract

To provide surface-coated inorganic particles with a good touch and suitable as an alternative material to synthetic polymer fine particles.SOLUTION: Surface-coated inorganic particles are provided in which part or all of the surface of inorganic particles (A) is coated with a surface treatment agent (B). The inorganic particles (A) contain silica particles or silicate mineral particles. The surface treatment agent (B) contains at least one kind selected from a modified silicone (b1) in liquid form at 25°C and a water-soluble cationic polymer (b2). The modified silicone (b1) contains at least one kind selected from a polyether-modified silicone, a polyglycerol-modified silicone, a branched polyglycerol-modified silicone and an alkylglyceryl ether-modified silicone.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to surface-coated inorganic particles, surface modifiers, cosmetics, surface modification methods, and methods for producing surface-coated inorganic particles. [Background technology]

[0002] Cosmetics, skincare products, toiletries, perfumes, and other cosmetic products may contain synthetic polymer microparticles to improve their texture. Here, synthetic polymer microparticles are difficult to decompose in the natural environment and pose a risk of adverse effects on ecosystems, so there is a need for texture-enhancing particles to replace synthetic polymer microparticles. Furthermore, examples of texture-enhancing particles incorporated into cosmetics include inorganic particles whose surfaces are coated with a silicone compound. Examples of technologies related to such surface-coated inorganic particles include those described in Patent Documents 1 and 2.

[0003] Patent Document 1 describes inorganic particles whose surface is coated with poly(N-acylalkyleneimine) modified silicone. Patent Document 2 describes a composite surface-treated inorganic powder in which a base powder mainly composed of inorganic materials is surface-treated with a cationic surfactant and an amino-modified silicone. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 9-301826 [Patent Document 2] International Publication No. 2020 / 230650 [Overview of the project] [Problems that the invention aims to solve]

[0005] There is a need for texture-enhancing particles that have a good feel and are suitable as an alternative material to synthetic polymer microparticles. One embodiment of the present invention relates to surface-coated inorganic particles, a surface modifier, and cosmetics that have a good feel and are suitable as an alternative material for synthetic polymer fine particles, and a surface modification method using the surface-coated inorganic particles, the surface modifier, or the cosmetics. Furthermore, one embodiment of the present invention relates to a method for producing surface-coated inorganic particles that have a good feel and are suitable as an alternative material for synthetic polymer fine particles.

Means for Solving the Problems

[0006] The present invention relates to the following [1] to [5]. 〔1〕Surface-coated inorganic particles in which part or all of the surface of inorganic particles (A) is coated with a surface treatment agent (B), The inorganic particles (A) include silica particles or silicate mineral particles, The surface treatment agent (B) includes at least one selected from modified silicone (b1) that is liquid at 25°C and a water-soluble cationic polymer (b2), The surface-coated inorganic particles in which the modified silicone (b1) includes at least one selected from polyether-modified silicone, polyglycerol-modified silicone, branched polyglycerol-modified silicone, and alkyl glyceryl ether-modified silicone. 〔2〕A surface modifier containing the surface-coated inorganic particles described in [1] above. 〔3〕Cosmetics containing the surface-coated inorganic particles described in [1] above. 〔4〕A surface modification method including a step of applying the surface-coated inorganic particles described in [1] above, the surface modifier described in [2] above, or the cosmetics described in [3] above to a target surface. 〔5〕A method for producing the surface-coated inorganic particles described in [1] above, including a step of mixing the inorganic particles (A) with a surface treatment agent solution containing the surface treatment agent (B) and a solvent.

Advantages of the Invention

[0007] According to one embodiment of the present invention, it is possible to provide surface-coated inorganic particles, a surface modifier, and a cosmetic product that have a good feel and are suitable as a substitute material for synthetic polymer fine particles, as well as a surface modification method using the surface-coated inorganic particles, the surface modifier, or the cosmetic product. Furthermore, according to one embodiment of the present invention, it is possible to provide a method for producing surface-coated inorganic particles that have a good feel and are suitable as an alternative material to synthetic polymer fine particles. [Modes for carrying out the invention]

[0008] [Surface coated inorganic particles] The surface-coated inorganic particles according to the present invention are surface-coated inorganic particles in which part or all of the surface of an inorganic particle (A) is coated with a surface treatment agent (B), wherein the inorganic particle (A) includes silica particles or silicate mineral particles, and the surface treatment agent (B) includes at least one selected from a modified silicone (b1) (hereinafter also referred to as "modified silicone (b1)") that is liquid at 25°C and a water-soluble cationic polymer (b2), wherein the modified silicone (b1) includes at least one selected from polyether-modified silicone, polyglycerin-modified silicone, branched polyglycerol-modified silicone and alkylglyceryl ether-modified silicone.

[0009] The surface-coated inorganic particles according to the present invention have a pleasant feel. Therefore, by incorporating these surface-coated inorganic particles into cosmetics or using them in cosmetics, the feel of the cosmetics can be improved. Furthermore, by using these surface-coated inorganic particles as a surface modifier, the surfaces of skin, hair, nails, etc., can be modified to have a pleasant feel. Furthermore, the surface-coated inorganic particles according to the present invention comprise inorganic particles (A) that do not fall under the category of synthetic polymer fine particles as core particles, and the inorganic particles (A) are coated with a surface treatment agent (B) that contains at least one selected from a modified silicone (b1) that is liquid at 25°C and a water-soluble cationic polymer (b2). Therefore, the inorganic particles (A) are environmentally friendly and suitable as an alternative material to synthetic polymer fine particles.

[0010] In this specification, "partially or entirely coated with surface treatment agent (B)" means that the surface treatment agent (B) is adsorbed on at least a portion of the surface of the inorganic particles (A) via intermolecular forces or ionic bonds. "Adsorption" as used herein does not include any covalent bonding between the inorganic particles (A) and the surface treatment agent (B). Whether or not the surface treatment agent (B) is adsorbed on at least a portion of the surface of the inorganic particles (A) is determined by a known method. For example, if the amount of surface treatment agent (B) adsorbed per 100 parts by mass of inorganic particles (A), calculated by "Measurement of the amount of surface treatment agent adsorbed on inorganic particles" described in the Examples, is greater than 0 parts by mass, preferably 0.1 parts by mass or more, and more preferably 0.5 parts by mass or more, then it is assumed that the surface treatment agent (B) is adsorbed on the surface of the inorganic particles (A). In this specification, "feel" refers to the smoothness and lack of squeaky feeling of particles when applied to skin, hair, nails, etc., with the smoother and less squeaky the particle, the better the feel. "Smoothness" refers to a feel that is smooth and not powdery, and "squeaky feeling" refers to a feeling of resistance or catching when fingers are moved over skin, hair, nails, etc. Furthermore, in this specification, "liquid at 25°C" means a state in which the material is fluid in a bulk state under 1 atmosphere and 25°C.

[0011] The reason why the surface-coated inorganic particles according to the present invention have a good feel is not entirely clear, but it is thought that by coating inorganic particles (A), which include silica particles or silicate mineral particles, with a surface treatment agent (B) containing at least one selected from modified silicone (b1) with excellent lubricity and a water-soluble cationic polymer (b2), the kinetic friction force and the amplitude of the kinetic friction force can be effectively reduced while maintaining the appropriate hardness of the inorganic particles (A).

[0012] The content of the synthetic polymer in the surface-coated inorganic particles according to the present invention, which is solid at 25°C and water-insoluble, is preferably less than 1% by mass, more preferably less than 0.5% by mass, even more preferably less than 0.1% by mass, and even more preferably less than 0.01% by mass, from the viewpoint of further improving environmental compatibility, and it is preferable that the surface-coated inorganic particles according to the present invention substantially contain the synthetic polymer. In this specification, "substantially contain the synthetic polymer" means that it has not been intentionally added, and does not exclude the presence of a small amount of the synthetic polymer as an impurity. In this specification, "water-insoluble synthetic polymer" refers to a synthetic polymer in which the amount of solubility is 2 g or less when 10 g of the synthetic polymer is mixed in 1000 mL of water at 20°C and pH 7, in accordance with OECD guideline 120, and stirred for 24 hours. Furthermore, "solid at 25°C" refers to a state in which the bulk material does not possess fluidity under 1 atmosphere and 25°C conditions.

[0013] The median particle size (D) of surface-coated inorganic particles according to the present invention 50 From the viewpoint of further improving the feel, the particle size is preferably greater than 1 μm, more preferably greater than 2 μm, even more preferably greater than 3 μm, and preferably 30 μm or less, more preferably 20 μm or less, even more preferably 15 μm or less, and even more preferably 12 μm or less. Here, the volume-intermediate particle size (D) according to the present invention 50 ) is the 50% median diameter measured by a particle size distribution analyzer using the laser diffraction / scattering method, and can be specifically measured by the method described in the examples.

[0014] From the viewpoint of further improving the feel, it is preferable that the surface-coated inorganic particles according to the present invention have a surface treatment agent (B) adsorbed on the surface of the inorganic particles (A) via intermolecular forces or ionic bonds. In this specification, the presence or absence of adsorption between inorganic particles (A) and surface treatment agent (B) due to intermolecular forces or ionic bonds can be confirmed by known methods, for example, by the change in the amount of adsorption after washing the surface-coated inorganic particles with a solvent in which the surface treatment agent (B) is soluble, and specifically by the method described in the examples.

[0015] The following describes each component constituting the surface-coated inorganic particles according to the present invention, and the method for producing the surface-coated inorganic particles.

[0016] <Inorganic particles (A)> The inorganic particles (A) include silica particles or silicate mineral particles. From the viewpoint of further improving the feel of the surface-coating inorganic particles, the inorganic particles (A) more preferably include at least one particle selected from silica particles, talc particles, and mica particles, even more preferably include at least one particle selected from silica particles and mica particles, and from the viewpoint of further suppressing stickiness as it dries, it is even more preferably to include silica particles, and even more preferably to include porous silica particles. From the viewpoint of further improving the feel of the surface-coating inorganic particles, the silicate mineral particles preferably contain at least one selected from talc particles, mica particles, sericite particles, smectite particles, montmorillonite particles, bentonite particles, and kaolin particles, more preferably contain at least one selected from talc particles and mica particles, and even more preferably contain mica particles.

[0017] When the inorganic particles (A) include porous silica particles, the specific surface area of ​​the porous silica particles is preferably 5 m², from the viewpoint of suppressing the collapse of the porous silica particles and further improving the feel of the surface-coating inorganic particles. 2 / g or more, comfortably 10m 2 It is 1000m or more per gram, and preferably 1000m 2 / g or less, more preferably 900m 2 It is less than or equal to / g. The specific surface area is the BET specific surface area measured in accordance with JIS Z 8830:2013.

[0018] When the inorganic particles (A) include porous silica particles, the pore volume of the porous silica particles is preferably 0.1 mL / g or more, more preferably 0.3 mL / g or more, even more preferably 0.5 mL / g or more, and preferably 5 mL / g or less, more preferably 3 mL / g or less, and even more preferably 2 mL / g or less, from the viewpoint of suppressing the collapse of the porous silica particles and further improving the feel of the surface-coating inorganic particles. Furthermore, from the viewpoint of eliminating the feeling of squeaking, it is preferably 0.3 mL / g or more, more preferably 0.5 mL / g or more, even more preferably 0.7 mL / g or more, and preferably 5 mL / g or less, more preferably 3 mL / g or less, even more preferably 2 mL / g or less, and even more preferably 1.5 mL / g or less. The aforementioned pore volume can be measured by gas adsorption. Examples of gas adsorption methods include JIS Z 8831-2:2010 (Pore size distribution and pore characteristics of powders (solids) - Part 2: Method for measuring mesopores and macropores by gas adsorption) and JIS Z 8831-3:2010 (Pore size distribution and pore characteristics of powders (solids) - Part 3: Method for measuring micropores by gas adsorption).

[0019] The content of at least one particle selected from silica particles and silicate mineral particles in the inorganic particles (A) is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and preferably 100% by mass or less, from the viewpoint of further improving the feel of the surface-coated inorganic particles.

[0020] Examples of the shape of the inorganic particles (A) include spherical, plate-shaped, flake-shaped, and irregularly shaped particles. Among these, from the viewpoint of further improving the feel of the surface-coating inorganic particles, spherical, plate-shaped, or flake-shaped particles are preferred, and spherical or flake-shaped particles are more preferred. More specifically, if the inorganic particles (A) are silica particles, they are more preferably spherical, and if the inorganic particles (A) are silicate mineral particles, they are more preferably flaky.

[0021] Volume median particle size (D) of inorganic particles (A) 50 From the viewpoint of further improving the feel of the surface-coated inorganic particles, the particle size is preferably 1 μm or more, more preferably 2 μm or more, even more preferably 3 μm or more, and preferably 30 μm or less, more preferably 20 μm or less, even more preferably 15 μm or less, and even more preferably 12 μm or less.

[0022] <Surface treatment agent (B)> The surface treatment agent (B) comprises at least one selected from a modified silicone (b1) that is liquid at 25°C and a water-soluble cationic polymer (b2), and it is more preferable to include a modified silicone (b1) that is liquid at 25°C from the viewpoint of further suppressing stickiness as it dries. From the viewpoint of further improving the feel and environmental compatibility of the surface-coated inorganic particles, the surface treatment agent (B) preferably contains 50% by mass or more of at least one selected from the modified silicone (b1) and the water-soluble cationic polymer (b2), more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and preferably 100% by mass or less.

[0023] The modified silicone (b1), which is liquid at 25°C, includes at least one selected from polyether-modified silicone, polyglycerin-modified silicone, branched polyglycerol-modified silicone, and alkylglyceryl ether-modified silicone, from the viewpoint of improving the feel of the surface-coating inorganic particles.

[0024] The HLB (hydrophilic-lipophilic balance) of the modified silicone (b1) is preferably 1.0 or higher, more preferably 2.0 or higher, even more preferably 2.5 or higher, and preferably 20.0 or lower, more preferably 18.0 or lower, even more preferably 16.0 or lower, even more preferably 15.5 or lower, even more preferably 15.0 or lower, even more preferably 10.0 or lower, even more preferably 5.0 or lower, even more preferably 4.0 or lower, and even more preferably 3.5 or lower, from the viewpoint of improving the feel of the surface-coating inorganic particles. Here, the HLB value is a value that indicates the affinity of the modified silicone (b1) for water and oil, and can be determined by the Griffin method using the following formula. HLB = 20 × [(Molecular weight of hydrophilic groups contained in modified silicone (b1)) / (Molecular weight of modified silicone (b1))] Examples of the hydrophilic groups mentioned above include hydroxyl groups and ethyleneoxy groups.

[0025] The viscosity of the modified silicone (b1) at 25°C is preferably 50 mPa·s or more, more preferably 100 mPa·s or more, even more preferably 200 mPa·s or more, even more preferably 400 mPa·s or more, and preferably 500,000 mPa·s or less, more preferably 100,000 mPa·s or less, and even more preferably 80,000 mPa·s or less. The viscosity described above can be measured at 25°C using a Brookfield viscometer, in accordance with JIS Z8803:2011 "Method for Measuring the Viscosity of Liquids".

[0026] Polyether-modified silicones have a structure in which the hydrocarbon groups at the side chains and / or terminals of a silicone oil are replaced with polyether groups. Suitable polyether groups for polyether-modified silicones include polyethylene oxy groups, polypropylene oxy groups, and polyalkylene oxy groups in which ethylene oxy groups (EO) and propylene oxy groups (trimethylene oxy groups or propane-1,2-diyl oxy groups; PO) are added in a block-like or random manner; polyethylene oxy groups are more preferred. As polyether-modified silicones, compounds in which polyether groups are grafted onto a silicone main chain, compounds in which silicone and polyether groups are bonded in a block-like manner, and the like can be used.

[0027] The viscosity of the polyether-modified silicone at 25°C is preferably 50 mPa·s or more, more preferably 100 mPa·s or more, even more preferably 150 mPa·s or more, even more preferably 400 mPa·s or more, even more preferably 450 mPa·s or more, even more preferably 500 mPa·s or more, even more preferably 540 mPa·s or more, and preferably 3000 mPa·s or less, more preferably 2000 mPa·s or less, even more preferably 1000 mPa·s or less, even more preferably 750 mPa·s or less, and even more preferably 600 mPa·s or less, from the viewpoint of improving the feel of the surface-coated inorganic particles. The viscosity described above can be measured at 25°C using a Brookfield viscometer, in accordance with JIS Z8803:2011 "Method for Measuring the Viscosity of Liquids".

[0028] Specific examples of polyether-modified silicones include PEG-3 dimethicone, PEG-9 dimethicone, PEG-9 methyl ether dimethicone, PEG-10 dimethicone, PEG-11 methyl ether dimethicone, PEG-12 dimethicone, PEG / PPG-20 / 22 butyl ether dimethicone, PEG-32 methyl ether dimethicone, PEG-9 polydimethylsiloxyethyl dimethicone, lauryl PEG-9 polydimethylsiloxyethyl dimethicone, cetyl PEG / PPG-10 / 1 dimethicone, PEG / PPG-30 / 10 dimethicone, and linear polyether-modified silicones in which dimethyl silicone units and polyether units are copolymerized alternately. Examples of commercially available polyether-modified silicones include, for example, the KF series from Shin-Etsu Chemical Co., Ltd. (e.g., KF-6004, KF-6011, KF-6012, KF-6013, KF-6015, KF-6016, KF-6017, KF-6028, KF-6038, KF-6043, KF-6048) and the DOWSIL series from Dow Chemical Japan Ltd. (BY25-339, SH3775M, FZ-2203).

[0029] Polyglycerin-modified silicones refer to silicones having monovalent polyglyceryl groups in their structure, such as polyglyceryl-3 disiloxane dimethicone, polyglyceryl-3 polydimethylsiloxyethyl dimethicone, and laurylpolyglyceryl-3 polydimethylsiloxyethyl dimethicone. Hereinafter, branched polyglycerol-modified silicones are excluded from the definition of polyglycerin-modified silicones. Examples of commercially available polyglycerin-modified silicones include the KF series manufactured by Shin-Etsu Chemical Co., Ltd. (e.g., KF-6100, KF-6104, KF-6106, KF-6105).

[0030] The viscosity of the polyglycerin-modified silicone at 25°C is preferably 500 mPa·s or more, more preferably 1,000 mPa·s or more, even more preferably 2,000 mPa·s or more, even more preferably 3,000 mPa·s or more, and preferably 20,000 mPa·s or less, more preferably 10,000 mPa·s or less, even more preferably 5,000 mPa·s or less, and even more preferably 4,000 mPa·s or less, from the viewpoint of improving the feel of the surface-coated inorganic particles. The viscosity described above can be measured at 25°C using a Brookfield viscometer, in accordance with JIS Z8803:2011 "Method for Measuring the Viscosity of Liquids".

[0031] Examples of the branched polyglycerol-modified silicone include compounds having a structure in which a branched polyglycerol chain is bonded via a linking group containing an oxyphenylene group at both ends of dimethylpolysiloxane, represented by the following formula (1).

[0032] [Chemical formula] (In formula (1), R 12 each independently represents a branched polyglycerol chain, and m represents an integer of 0 or more and 10,000 or less.)

[0033] In formula (1), the bonding mode of the oxygen atom and the trimethylene group (-C3H6-) in the phenylene group portion is not particularly limited and may be any of ortho, meta, and para positions. m represents an integer of 0 or more and 10,000 or less, preferably 1 or more and 300 or less. R 12 represents a branched polyglycerol chain, which is composed of glycerol units represented by the following structural formulas (2) to (5), has at least one glycerol unit having a branched structure represented by structural formula (2), and the terminal is a glycerol unit represented by structural formula (5). The average total number of bonds of glycerol units in the branched polyglycerol chain is 3 or more and 200 or less, preferably 3 or more and 30 or less.

[0034] [Chemical formula]

[0035] From the viewpoint of improving the feel of the surface-coated inorganic particles, the viscosity of the branched polyglycerol-modified silicone at 25°C is preferably 10,000 mPa·s or more, more preferably 20,000 mPa·s or more, still more preferably 40,000 mPa·s or more, still more preferably 60,000 mPa·s or more, still more preferably 70,000 mPa·s or more, and preferably 500,000 mPa·s or less, more preferably 100,000 mPa·s or less, still more preferably 80,000 mPa·s or less. The viscosity described above can be measured at 25°C using a Brookfield viscometer, in accordance with JIS Z8803:2011 "Method for Measuring the Viscosity of Liquids".

[0036] The branched polyglycerol-modified silicone represented by formula (1) can be produced, for example, by the method described in Japanese Patent Application Publication No. 2004-339244, which involves graft polymerization of a modified silicone having phenyl groups substituted with hydroxyl groups at both ends by adding 2,3-epoxy-1-propanol in the presence of an acidic or basic catalyst, or by other generally known methods. Furthermore, commercially available branched polyglycerol-modified silicones include, for example, Sofcare GS-G (manufactured by Kao Corporation).

[0037] Examples of alkylglyceryl ether-modified silicones include those represented by the following formula (6).

[0038] [ka] [In formula (6), Q represents a divalent hydrocarbon group having 3 to 20 carbon atoms, and R 1 ~R 9 R may be the same or different, and represents a hydrogen atom, a linear or branched hydrocarbon group having 1 to 32 carbon atoms, or a phenyl group. 10 and R 11 R may be the same or different, and represents a hydrogen atom or a linear or branched hydrocarbon group having 1 to 32 carbon atoms, and multiple Rs within the same molecule 10 and R 11 These may be different. p represents a number between 1 and 500, and q represents a number between 1 and 50. Note that p and q represent the alkylglyceryl ether group [-Q-OCH2-CH(OR 10 )-CH2(OR 11 It is preferable to indicate a number such that the content of ) is between 1% by mass and 50% by mass.

[0039] In formula (6), the divalent hydrocarbon group having 3 to 20 carbon atoms represented by Q is preferably a linear or branched alkylene group having 3 to 20 carbon atoms. More specifically, examples include linear alkylene groups such as trimethylene, tetramethylene, pentamethylene, hexamethylene, heptamethylene, octamethylene, nonamethylene, decamethylene, undecamethylene, dodecamethylene, tetradecamethylene, hexadecamethylene, and octadecamethylene; and branched alkylene groups such as propylene, 2-methyltrimethylene, 2-methyltetramethylene, 2-methylpentamethylene, and 3-methylpentamethylene.

[0040] Also, R 1 ~R 11 In the definition of R, examples of linear or branched hydrocarbon groups having 1 to 32 carbon atoms include linear alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, undecyl, dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, doeicosyl, tetraeicosyl, hexaeicosyl, octaeicosyl, and triacontyl; and branched alkyl groups such as isopropyl, sec-butyl, tert-butyl, neopentyl, 1-ethylpropyl, and 1-heptyldecyl. In this specification, R 1 ~R 9 A linear or branched alkyl group having 1 to 25 carbon atoms is preferred (however, some may be hydrogen atoms), and a linear or branched alkyl group having 1 to 22 carbon atoms is more preferred (however, some may be hydrogen atoms). Also, R 10 , R 11 A hydrogen atom or an alkyl group having 1 to 5 carbon atoms is preferred, and a hydrogen atom is even more preferred.

[0041] Furthermore, p and q are alkylglyceryl ether groups [-Q-OCH2-CH(OR 10 )-CH2(OR 11A number is preferred in which the content of ) is 1% by mass or more and 50% by mass or less, more preferably 5% by mass or more and 40% by mass or less, and even more preferably 10% by mass or more and 30% by mass or less. Specifically, from the standpoint of the ease of obtaining the organopolysiloxane used as a raw material and the ease of handling during manufacturing, p is in the range of 1 to 500, preferably in the range of 10 to 30, and q is in the range of 1 to 50, preferably in the range of 1 to 30.

[0042] The viscosity of alkylglyceryl ether-modified silicone at 25°C is preferably 1,000 mPa·s or more, more preferably 2,000 mPa·s or more, even more preferably 3,000 mPa·s or more, even more preferably 4,000 mPa·s or more, even more preferably 5,000 mPa·s or more, even more preferably 6,000 mPa·s or more, and preferably 20,000 mPa·s or less, more preferably 10,000 mPa·s or less, even more preferably 8,000 mPa·s or less, and even more preferably 7,000 mPa·s or less, from the viewpoint of improving the feel of the surface-coating inorganic particles. The above viscosity can be measured at 25°C using a Brookfield viscometer in accordance with JIS Z8803:2011 "Method for measuring the viscosity of liquids".

[0043] Such alkylglyceryl ether-modified silicones can be produced by reacting an organohydrogenpolysiloxane having at least one silicon-hydrogen bond with the corresponding alkenyl glyceryl ether, according to the methods described in Japanese Patent Publication No. 4-134013 and Japanese Patent Publication No. 2005-194523. Furthermore, commercially available alkylglyceryl ether-modified silicones include, for example, SI-UGE and Sofcare RS-U (both manufactured by Kao Corporation).

[0044] These modified silicones (b1) may be used individually or in combination of two or more types.

[0045] The water-soluble cationic polymer (b2) preferably contains at least one selected from cationic polymers having a cellulose skeleton, cationic vinyl polymers, chitin / chitosans, and halogenated hexadimethrins, more preferably contains at least one selected from cationic polymers having a cellulose skeleton, cationic vinyl polymers, chitin / chitosans, bromide hexadimethrin, and chloride hexadimethrins, preferably contains at least one selected from cationic polymers having a cellulose skeleton, cationic vinyl polymers, and chitin / chitosans, even more preferably contains at least one selected from cationic polymers having a cellulose skeleton and cationic vinyl polymers, and even more preferably contains a cationic vinyl polymer. In this specification, "water-soluble polymer" refers to a polymer in which the amount of polymer dissolved when 10 g of the polymer is mixed with 1000 mL of water at 20°C and pH 7 and allowed to stand for 24 hours exceeds 2 g. The water-soluble cationic polymer (b2) preferably has basic groups such as primary to tertiary amino groups, quaternary ammonium groups, and hydrazino groups, and more preferably has tertiary amino groups or quaternary ammonium groups. The basic groups include those neutralized with acids such as hydrochloric acid, sulfuric acid, nitric acid, acetic acid, formic acid, maleic acid, fumaric acid, citric acid, tartaric acid, adipic acid, and lactic acid. Furthermore, in this specification, water-soluble cationic silicones such as water-soluble amino-modified silicones are excluded from the water-soluble cationic polymer (b2).

[0046] The weight-average molecular weight Mw of the water-soluble cationic polymer (b2) is preferably 3,000 or more, more preferably 5,000 or more, even more preferably 15,000 or more, even more preferably 50,000 or more, and even more preferably 100,000 or more, from the viewpoint of improving the feel of the surface-coated inorganic particles. It is also preferably 5 million or less, more preferably 3 million or less, and even more preferably 2 million or less. The above weight-average molecular weight Mw can be measured by gel permeation chromatography (GPC) using polyethylene glycol as a standard substance. For example, the weight-average molecular weight Mw of cationized hydroxyethyl cellulose, which is a water-soluble cationic polymer (b2), can be determined by performing GPC measurement under the following conditions. <GPC Measurement Conditions> Sample concentration: 1 mg / mL Columns: Two TSKgel α-M columns (Tosoh Corporation) Eluent: 0.15 mol / L sodium sulfate aqueous solution (containing 1% acetic acid) [[ID=ID=10]]Flow rate: 1.0 mL / min Column temperature: 40 °C Detector: Differential refractive index detector

[0047] In this specification, the "cationic polymer having a cellulose skeleton" means a polymer having a cationic group and a cellulose skeleton and being a cationic charge as a whole. The cationic group refers to a cationic group or a group that can be ionized to become a cationic group, and examples thereof include a primary amino group, a secondary amino group, a tertiary amino group, a quaternary ammonium group, and the like. Examples of the cationic polymer having a cellulose skeleton include cationized cellulose, cationized cellulose derivatives, and the like. Specifically, cationized cellulose, cationized hydroxyethyl cellulose, cationized hydroxypropyl cellulose, cationized carboxymethyl cellulose, and the like can be mentioned. As the cationic polymer having a cellulose skeleton, cationized hydroxyethyl cellulose is preferable, and a polymer of a quaternary ammonium salt (INCI name: Polyquaternium-10) obtained by adding glycidyltrimethylammonium chloride to hydroxyethyl cellulose is more preferable.

[0048] Examples of cationic vinyl polymers include vinylpyrrolidone / dimethylaminoethyl methacrylate copolymer diethyl sulfate, vinylpyrrolidone / dimethylaminopropyl methacrylamide / lauryldimethylaminopropyl methacrylamide copolymer, vinylpyrrolidone / N,N-dimethylaminoethyl methacrylate / alkyl acrylate / tripropylene glycol diacrylate copolymer, polydimethylmethylene piperidinium chloride, dimethyldiallylammonium chloride / acrylamide copolymer, trimethylammoniopropylacrylamide chloride / dimethylacrylamide copolymer, alkylacrylamide / acrylate / alkylaminoalkylacrylamide Examples include mid / polyethylene glycol methacrylate copolymer, t-butylacrylamide / dimethylacrylamide / dimethylaminopropylacrylamide / methoxypolyethylene glycol methacrylate copolymer, vinylpyrrolidone / N,N-dimethylaminoethyl methacrylate copolymer diethyl sulfate, vinylpyrrolidone / dimethylaminoethyl methacrylate copolymer, N,N-dimethylaminoethyl methacrylate diethyl sulfate / N,N-dimethylacrylamide / polyethylene glycol dimethacrylate copolymer, ammonium-modified hydroxyethylcellulose, acrylamide / DMAPA acrylate / methoxyPEG methacrylate copolymer, etc. Among these, tertiary amino group-containing (meth)acrylic polymers are preferred, and acrylamide / DMAPA acrylate / methoxyPEG methacrylate copolymer is more preferred.

[0049] Examples of chitin and chitosan compounds include chitin and chitosan derivatives such as hydroxypropyl chitosan, carboxymethyl chitin, and carboxymethyl chitosan, as well as chitin and chitosan, with chitosan being preferred.

[0050] These water-soluble cationic polymers (b2) may be used individually or in combination of two or more.

[0051] The surface treatment agent (B) may include surface treatment agents other than modified silicone (b1) and water-soluble cationic polymer (b2). Examples of surface treatment agents other than modified silicone (b1) and water-soluble cationic polymer (b2) include surface treatment agents applied to cosmetic particles.

[0052] The content of at least one of the modified silicone (b1) and water-soluble cationic polymer (b2) in the surface treatment agent (B) is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 80% by mass or more, even more preferably 90% by mass or more, even more preferably 95% by mass or more, and preferably 100% by mass or less, from the viewpoint of further improving the feel of the surface-coated inorganic particles and further improving environmental compatibility.

[0053] From the viewpoint of further improving environmental compatibility, the content of the synthetic polymer in the surface treatment agent (B) that is solid at 25°C and water-insoluble is preferably less than 10% by mass, more preferably less than 5% by mass, even more preferably less than 1% by mass, even more preferably less than 0.1% by mass, and even more preferably less than 0.01% by mass, and it is preferable that the surface treatment agent (B) is substantially free of the synthetic polymer.

[0054] In the surface-coated inorganic particles according to the present invention, the amount of surface treatment agent (B) adsorbed onto the inorganic particles (A) is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, even more preferably 0.7 parts by mass or more, even more preferably 0.9 parts by mass or more, even more preferably 1.0 part by mass or more, even more preferably 1.5 parts by mass or more, even more preferably 2.0 parts by mass or more, even more preferably 2.5 parts by mass or more, and preferably 50 parts by mass or less, more preferably 30 parts by mass or less, even more preferably 20 parts by mass or less, even more preferably 15 parts by mass or less, even more preferably 13 parts by mass or less, even more preferably 10 parts by mass or less, and even more preferably 8 parts by mass or less. The amount of surface treatment agent (B) adsorbed can be measured by the method described in the examples.

[0055] <Fine particles (C)> In the present invention, from the viewpoint of further improving the feel and providing a high adhesion suppression effect to airborne harmful substances, part or all of the surface of the inorganic particle (A) may be coated with a surface treatment agent (B), and further, part or all of the surface of the inorganic particle (A) may be coated with fine particles (C). In this invention, "atmospheric hazardous substances" refers to pollen from cedar, cypress, etc.; air pollutants such as sulfur oxides, soot, nitrogen oxides, etc., particulate matter, automobile exhaust gases, hazardous air pollutants such as benzene, trichloroethylene, tetrachloroethylene, etc., and particles containing volatile organic compounds (VOCs); and hazardous substances suspended in the atmosphere such as yellow dust (including PM2.5). The mechanism by which the adhesion suppression effect is exhibited is not clear, but it is thought to be as follows: Surface-coated inorganic particles, in which part or all of the surface of inorganic particles (A) is covered with fine particles (C), form localized nano-sized irregularities on the solid surface when applied to the solid surface. When atmospheric hazardous substances come into contact with such a surface, the contact area becomes smaller, and it is thought that the adhesion of the hazardous substances can be effectively suppressed.

[0056] From the viewpoint of further improving the feel and improving the adhesion suppression effect, the fine particles (C) preferably contain at least one selected from silica particles, silicate mineral particles, and zinc oxide particles, and more preferably contain silica particles. Volume median particle size (D) of fine particles (C) 50 From the viewpoint of further improving the feel and improving the adhesion suppression effect, the wavelength is preferably 1 nm to 1 μm, more preferably 3 nm to 500 nm, and even more preferably 5 nm to 300 nm.

[0057] Furthermore, the volume median particle size ratio (A / C) of inorganic particles (A) to fine particles (C) is preferably 10 to 30,000, more preferably 20 to 5,000, and even more preferably 30 to 1,000, from the viewpoint of further improving the feel and improving the adhesion suppression effect.

[0058] [Method for producing surface-coated inorganic particles] The surface-coated inorganic particles according to the present invention can be obtained by coating inorganic particles (A) with a surface treatment agent (B). Specifically, from the viewpoint of coating the inorganic particles (A) with a surface treatment agent (B), the method for producing surface-coated inorganic particles preferably includes a step of mixing inorganic particles (A) with a surface treatment agent solution containing the surface treatment agent (B) and a solvent, and more preferably includes a step of mixing an inorganic particle dispersion containing inorganic particles (A) and solvent A with a surface treatment agent solution containing the surface treatment agent (B) and solvent B. As the solvent, water or an organic solvent can be used. The organic solvent is not particularly limited, but for example, alcohols such as methanol, ethanol, 1-propanol, and 2-propanol can be used. Among these alcohols, at least one selected from ethanol and 2-propanol is more preferred, and ethanol is even more preferred.

[0059] Solvents A and B may be the same, or they may be different as long as they are miscible. The solvent A used in the inorganic particle dispersion is preferably at least one selected from water and ethanol, from the viewpoint of dispersibility of the inorganic particles (A). When the surface treatment agent (B) contains modified silicone (b1), the solvent used in the surface treatment agent solution is preferably an organic solvent from the viewpoint of solubility of the modified silicone (b1), and more preferably ethanol from the viewpoint of compatibility with solvent A. When the surface treatment agent (B) contains a water-soluble cationic polymer (b2), the solvent used in the surface treatment agent solution is preferably at least one selected from water and ethanol, and more preferably water, from the viewpoint of solubility of the water-soluble cationic polymer (b2). Furthermore, from the viewpoint of improving the solubility of the water-soluble cationic polymer (b2), an organic acid such as lactic acid may be added to the surface treatment agent solution.

[0060] When using the inorganic particle dispersion, the concentration of inorganic particles (A) in the inorganic particle dispersion is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, and also preferably 40% by mass or less, more preferably 30% by mass or less, even more preferably 20% by mass or less, and even more preferably 10% by mass or less, from the viewpoint of efficiently adsorbing the surface treatment agent (B) onto the surface of the inorganic particles (A). When using the surface treatment agent solution, the concentration of the surface treatment agent (B) in the surface treatment agent solution is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, and also preferably 40% by mass or less, more preferably 30% by mass or less, even more preferably 20% by mass or less, and even more preferably 10% by mass or less, from the viewpoint of efficiently adsorbing the surface treatment agent (B) onto the inorganic particle (A) surface.

[0061] The temperature at which the inorganic particles (A) or the inorganic particle dispersion is mixed with the surface treatment agent solution is preferably 5°C or higher, more preferably 10°C or higher, from the viewpoint of efficiently adsorbing the surface treatment agent (B) onto the surface of the inorganic particles (A), and preferably 70°C or lower, more preferably 50°C or lower, from the viewpoint of suppressing the volatilization of the solvent. Furthermore, the mixing time between the inorganic particles (A) or the inorganic particle dispersion and the surface treatment agent solution is preferably 5 minutes or more, more preferably 10 minutes or more, from the viewpoint of sufficient adsorption of the surface treatment agent (B) onto the surface of the inorganic particles (A), and preferably 12 hours or less, more preferably 6 hours or less, from the viewpoint of manufacturing efficiency. In the step of mixing inorganic particles (A) or the inorganic particle dispersion with the surface treatment agent solution, a known stirring device can be used.

[0062] The mixture obtained by the above process can be separated using known methods such as centrifugation, filtration, decantation, and drying to recover the surface-coated inorganic particles. The obtained surface-coated inorganic particles may be classified using a sieve or the like to adjust their particle size.

[0063] If the surface-coated inorganic particles are further coated with fine particles (C), it is preferable to include a step of mixing a dispersion of fine particles (C) after the step of mixing the inorganic particles (A) with a surface treatment agent solution containing a surface treatment agent (B) and a solvent. The preferred range for the mixing temperature and mixing time in this case is the same as described above.

[0064] [Surface modifier] The surface-coated inorganic particles according to the present invention can be applied to surface modifiers. In other words, the surface modifier according to the present invention includes surface-coated inorganic particles according to the present invention. In this specification, "surface modifier" refers to a substance that can improve the feel of the surface of skin, hair, nails, etc. The content of the surface-coating inorganic particles according to the present invention in the surface modifier according to the present invention is not particularly limited as it is appropriately set according to the type of surface modifier, but for example it is 0.1% by mass or more, preferably 1% by mass or more, and for example it is 50% by mass or less, preferably 30% by mass or less, and more preferably 10% by mass or less.

[0065] The surface modifier according to the present invention may appropriately contain optional components used depending on the type of surface modifier, as long as they do not hinder the effects of the present invention. Examples of optional components other than the surface-coated inorganic particles according to the present invention include ultraviolet absorbers, oils, surfactants, water-soluble polymers, thickeners, neutralizing agents, propellants, pH adjusters, bactericides, anti-inflammatory agents, preservatives, colorants, chelating agents, whitening agents, blood circulation promoters, cooling agents, antiperspirants, insect repellents, physiologically active ingredients, salts, moisturizers, antioxidants, fragrances, plant extracts, and the like.

[0066] Examples of the surface modifier according to the present invention include liquid, emulsion, cream, paste, gel, wax, and solid forms. The surface modifier according to the present invention can also be applied to, for example, sheets, sprays, mousses, and the like. The surface modifier according to the present invention can be applied to, for example, skin (including lips), hair, nails, etc., and is preferably used by application.

[0067] From the viewpoint of further improving environmental compatibility, the content of synthetic polymer fine particles in the surface modifier according to the present invention is preferably less than 0.01% by mass, more preferably less than 0.005% by mass, and even more preferably less than 0.001% by mass. In this specification, synthetic polymer fine particles contain 1% by mass or more of a synthetic polymer that is solid at 25°C and water-insoluble, and have a medium volume particle size (D 50 This refers to fine particles with a diameter of 0.1 μm or more and a length of 5 mm or less.

[0068] The method for producing the surface modifier according to the present invention is not particularly limited, and for example, it can be produced by stirring and mixing each component using a known apparatus.

[0069] [Cosmetics] The surface-coated inorganic particles according to the present invention can be incorporated into or applied to various cosmetics. In other words, the cosmetic product according to the present invention contains surface-coated inorganic particles according to the present invention. The content of the surface-coated inorganic particles according to the present invention in the cosmetic product according to the present invention is set appropriately according to the type of cosmetic product and is not particularly limited, but for example it is 0.1% by mass or more, preferably 1% by mass or more, and for example it is 50% by mass or less, preferably 30% by mass or less. In this specification, "cosmetics" refers to products that come into direct contact with the human body, such as cosmetics, skincare products, toiletries, and perfumes.

[0070] The cosmetic product according to the present invention may appropriately contain optional components used depending on the type of cosmetic product, as long as they do not hinder the effects of the present invention. Examples of optional components other than surface-coated inorganic particles according to the present invention include ultraviolet absorbers, oils, surfactants, water-soluble polymers, thickeners, neutralizing agents, propellants, pH adjusters, bactericides, anti-inflammatory agents, preservatives, colorants, chelating agents, whitening agents, blood circulation promoters, cooling agents, antiperspirants, insect repellents, physiologically active ingredients, salts, moisturizers, antioxidants, fragrances, plant extracts, and the like.

[0071] Examples of the forms of the cosmetic product according to the present invention include liquid, emulsion, cream, paste, gel, wax, and solid forms. The cosmetic product according to the present invention can also be applied to, for example, sheet formulations, spray formulations, mousse formulations, and the like. The cosmetic product according to the present invention can be applied to, for example, the skin (including the lips), hair, nails, etc., and is preferably used by applying it topically.

[0072] From the viewpoint of further improving environmental compatibility, the content of synthetic polymer fine particles in the cosmetic product according to the present invention is preferably less than 0.01% by mass, more preferably less than 0.005% by mass, and even more preferably less than 0.001% by mass.

[0073] The method for producing the cosmetic product according to the present invention is not particularly limited, and for example, it can be produced by stirring and mixing each component using a known apparatus.

[0074] [Surface modification method] The surface modification method according to the present invention includes the step of applying the above-mentioned surface-coated inorganic particles, the above-mentioned surface modifier, or the above-mentioned cosmetic product according to the present invention to a target surface. Examples of target surfaces include skin, hair, and nails, with skin being preferred. Methods for applying the surface-coated inorganic particles, surface modifier, or cosmetic product according to the present invention to a target surface include, for example, coating, spraying, or casting onto the target surface, or immersing the target object in the surface-coated inorganic particles, surface modifier, or cosmetic product according to the present invention. [Examples]

[0075] The present invention will be described below with reference to examples, but the present invention is not limited to the scope of these examples. In these examples and comparative examples, various measurements and evaluations were performed by the following methods.

[0076] [Measurement and evaluation methods] (1) Measurement of the amount of surface treatment agent adsorbed onto inorganic particles The amount of surface treatment agent adsorbed was determined by thermogravimetric differential thermal analysis (TG-DTA) of the sample using a Rigaku Corporation thermal analyzer (Thermo plus EVO2 TG-DTA8122). The measurement conditions were as follows. Sample preparation: Surface-coated inorganic particles obtained in the examples and comparative examples, and inorganic particles before surface coating (approximately 30 mg (precise weighing)) Heating rate: 10℃ / min Measurement temperature range: 35~800℃ Measurement atmosphere: Air (180 mL / min) In the obtained TG-DTA curve, the amount of surface treatment agent adsorbed per 100 parts by mass of inorganic particles was calculated using the following equation. Here, the amount of surface treatment agent adsorbed on the surface-coated inorganic particles is denoted as x by mass % (the total amount of surface-coated inorganic particles is assumed to be 100% by mass). Amount of surface treatment agent adsorbed per 100 parts by mass of inorganic particles (parts by mass) = x / (100 - x) × 100 x is calculated from the following equation. A × x / 100 + A × (1 - x / 100) × y = B A: Mass (mg) of the sample of surface-coated inorganic particles B: Mass loss (mg) of surface-coated inorganic particles from 100°C to 800°C y: Mass loss rate of inorganic particles from 100°C to 800°C before surface coating (= Mass loss of inorganic particles from 100°C to 800°C before surface coating / Mass of the inorganic particle sample before surface coating)

[0077] (2) Volume median particle size (D) of inorganic particles, fine particles and surface-coated inorganic particles50 ) measurement Using a laser diffraction / scattering particle size distribution analyzer LA-960 manufactured by Horiba, Ltd., distilled water was added to the measurement cell, and the particle size distribution of inorganic particles and surface-coated inorganic particles was measured at a concentration that resulted in an appropriate absorbance range. From the obtained particle size distribution, the median volume particle size (D) of inorganic particles, fine particles, and surface-coated inorganic particles was determined. 50 The following values ​​were calculated for each of them.

[0078] (3) Sensory evaluation (3-1) Lack of creaking and smoothness Under conditions of 20-25°C and 25-40%RH humidity, 0.2g of the particles obtained in the examples and comparative examples were uniformly applied to the inner side of the forearm using a finger. The application was then rubbed with a finger to evaluate the lack of squeaky feeling and smoothness, respectively, and scored according to the following criteria. Three expert panelists were selected to evaluate each sample shown in the table below, focusing on the "lack of squeaking" and "smoothness" characteristics of the reference sample (lauryl methacrylate / ethylene glycol dimethacrylate / sodium methacrylate copolymer particles, medium volume particle size (D 50 The samples were evaluated in comparison to a standard sample (2 μm, manufactured according to Example 1 of Japanese Patent Publication No. 2006-8980). A score of "5" was given for samples that were equivalent to the standard sample and had very good smoothness and lack of squeaking; a score of "4" was given for samples that were slightly inferior to the standard sample but had good smoothness and lack of squeaking; a score of "3" was given for samples that were inferior to the standard sample but had average smoothness and lack of squeaking; a score of "2" was given for samples that were inferior to the standard sample and had poor smoothness and lack of squeaking; and a score of "1" was given for samples that were extremely inferior to the standard sample and had very poor smoothness and lack of squeaking. The average score of the evaluators was used. Each evaluator assigned a score in increments of 0.5, including an intermediate score. Here, the lauryl methacrylate / ethylene glycol dimethacrylate / sodium methacrylate copolymer particles correspond to polymer particles commonly used as texture-enhancing particles.

[0079] (3-2) Duration of sensation Under conditions of 20-25°C and 25-40%RH humidity, 0.2g of the particles obtained in the examples and comparative examples were uniformly applied to the inner side of the forearm using a finger, and then the entire applied area was rubbed 10 times with the finger. After that, the lack of squeaky feeling and smoothness were evaluated by rubbing the applied area with a finger, and the scores were assigned according to the same criteria as in (3-1) above.

[0080] (3-3) Stickiness as it dries Under conditions of 20-25°C and 25-40% RH humidity, 0.1 mL of a 5% by mass water / ethanol dispersion of the particles obtained in the examples and comparative examples (particles / water / ethanol = 5 / 70 / 25 (by mass ratio)) was applied to the inner forearm in an area of ​​approximately 5 cm in diameter and spread over 10 seconds. The stickiness at the drying stage was evaluated and scored according to the following criteria. Three expert panelists were selected to evaluate the "stickiness at the point of drying" for each sample shown in the table below. The reference sample (lauryl methacrylate / ethylene glycol dimethacrylate / sodium methacrylate copolymer particles, medium volume particle size (D 50 The samples were evaluated in comparison to a reference sample (2 μm, manufactured according to Example 1 of Japanese Patent Publication No. 2006-8980). A score of "5" was given for samples that were equivalent to the reference sample and had very good stickiness at the drying stage; a score of "4" was given for samples that were slightly inferior to the reference sample but had good stickiness at the drying stage; a score of "3" was given for samples that were inferior to the reference sample but had average stickiness at the drying stage; a score of "2" was given for samples that were inferior to the reference sample and had poor stickiness at the drying stage; and a score of "1" was given for samples that were extremely inferior to the reference sample and had very poor stickiness at the drying stage. The average score of the evaluators was used. Each evaluator assigned a score in increments of 0.5, including an intermediate score.

[0081] (4) Adhesion suppression rate A 5% by mass water / ethanol dispersion of the particles obtained in Examples 20 and 21 (particles / water / ethanol = 5 / 70 / 25 (mass ratio)) was attached to a 4cm square piece of white artificial leather (Laforet, manufactured by Okamoto Shinwa Co., Ltd.) as a substitute for skin, with a particle attachment amount of 0.1 mg / cm². 2The artificial leather was coated with the specified amount and dried at room temperature for 24 hours. The resulting artificial leather was then subjected to a 2.5 mg / cm³ test using a mesh sieve ("Test sieves JIS Z 8801" manufactured by Tokyo Screen Co., Ltd., frame dimensions: φ100 × 45H, mesh opening: 75 μm) and a clogging removal brush ("JNB-5" manufactured by Tokyo Screen Co., Ltd., mesh opening: 106 μm or less, brush diameter: 53 μm) while classifying the sample. 2 The artificial leather was sprayed to achieve the desired amount of adhesion. The obtained artificial leather was attached to the inner bottom surface of a polystyrene petri dish using double-sided tape. The petri dish was placed with the surface to which the atmospheric hazardous substances for evaluation had adhered facing downwards. A 100g weight was dropped from a height of 2cm from the center of the outer bottom surface of the petri dish, impacting the petri dish and causing the excess atmospheric hazardous substances to fall off. Nine fields of view of the surface of the obtained artificial leather were photographed at 100x magnification using a digital microscope (Keyence Corporation "VHX-1000"). The captured images were analyzed using image analysis software (Rasband,WS "Image J") to measure the percentage of the area occupied by the atmospheric hazardous substances adhesion. The above procedure was repeated three times, and the average value of the atmospheric hazardous substance adhesion rate (atmospheric hazardous substance adhesion rate of particles) was calculated. The average value of the atmospheric hazardous substance adhesion rate when no particles were applied (atmospheric hazardous substance adhesion rate of the blank) was similarly measured, and the adhesion suppression rate defined by the following formula was calculated. A higher adhesion suppression rate indicates a better adhesion suppression effect. Adhesion suppression rate (%) = (1 - Adhesion rate of airborne hazardous substances to particles / Adhesion rate of airborne hazardous substances to blank particles) × 100

[0082] [Manufacture of surface-coated inorganic particles] Example 1 A polyether-modified silicone solution was prepared by adding 2 g of polyether-modified silicone 1 (PEG-10 dimethicone, Shin-Etsu Chemical Co., Ltd. "KF-6017", HLB: 4.5, viscosity at 25°C: 490 mPa·s) and 98 g of ethanol to a 500 mL beaker. In a separately prepared 500 mL beaker, add the inorganic particles silica 1 (porous silica particles, JGC Catalysts & Chemicals Co., Ltd. "HCS 160M5") and the medium volume particle size (D 50 2 g of (pore size: 5 μm, pore volume: 0.7 mL / g) and 98 g of ethanol were added, and the mixture was treated with an ultrasonic homogenizer (ULTRASONIC HOMOGENIZER US-600E, manufactured by Nippon Seiki Seisakusho Co., Ltd.) at 200 W for 5 minutes to obtain a particle dispersion. The obtained particle dispersion was mixed with the polyether-modified silicone solution and stirred with a magnetic stirrer at 600 rpm for 1 hour at room temperature. The resulting mixture was separated into particles (dispersed phase) and solution (dispersion medium) by centrifugation at 3000 rpm for 30 minutes using a HITACHI CR21G III centrifuge. After removing the supernatant, the precipitate was dried overnight under reduced pressure at 50°C to obtain surface-coated inorganic particles. The obtained surface-coated inorganic particles were evaluated. The results are shown in the table below.

[0083] Examples 2-6 and 9-11 Surface-coated inorganic particles were obtained in the same manner as in Example 1, except that the types of inorganic particles and surface treatment agents were changed to those listed in the table below. Each of the obtained surface-coated inorganic particles was evaluated. The results are shown in the table below.

[0084] Examples 7, 12, 14 Surface-coated inorganic particles were obtained in the same manner as in Example 1, except that the types of inorganic particles and surface treatment agents were changed to those listed in the table below, and "ethanol 98g" was replaced with "water 98g". Each of the obtained surface-coated inorganic particles was evaluated. The results are shown in the table below.

[0085] Examples 8 and 13 Surface-coated inorganic particles were obtained in the same manner as in Example 1, except that the types of inorganic particles and surface treatment agents were changed to those listed in the table below, "ethanol 98g" was replaced with "water 98g", and 40 mg of 90% lactic acid (product name: Musashino Lactic Acid 90, manufactured by Musashino Chemical Research Institute Co., Ltd.) was added to the obtained cationic vinyl polymer solution 1. Each of the obtained surface-coated inorganic particles was evaluated. The results are shown in the table below.

[0086] Examples 15-19 Surface-coated inorganic particles were obtained in the same manner as in Example 1, except that the mixing ratio of the surface treatment agent was changed so that the amount of surface treatment agent adsorbed was as shown in the table below. Each of the obtained surface-coated inorganic particles was evaluated. The results are shown in the table below.

[0087] Comparative Example 1 Inorganic particles were obtained by processing in the same manner as in Example 1, except that 2g of ethanol was used instead of 2g of polyether-modified silicone. The obtained inorganic particles were evaluated. The results are shown in the table below.

[0088] [Table 1]

[0089] [Table 2]

[0090] [Table 3]

[0091] [Table 4]

[0092] [Table 5]

[0093] The ingredients listed in the table are as follows:

[0094] (Inorganic particles) • Silica 1 (porous silica particles, "HCS 160M5" manufactured by JGC Catalysts & Chemicals Co., Ltd., medium volume particle size (D 50 ):5μm, pore volume:0.7mL / g, spherical) • Silica 2 (porous silica particles, "Sunsphere H-51" manufactured by AGC SI-TEC Co., Ltd., medium volume particle size (D 50 ): 5 μm, pore volume: 1 mL / g, specific surface area: 800 m² 2 / g, spherical) • Talc 1 (Talc particles, manufactured by Asada Flour Milling Co., Ltd. "JA-13R", medium volume particle size (D 50 ):6μm, flaky) • Mica 1 (Mica particles, "Y-1800" manufactured by Yamaguchi Mica Co., Ltd., medium volume particle size (D 50 ):10μm, flaky)

[0095] (Surface treatment agent) • Polyether-modified silicone 1 (PEG-10 dimethicone, manufactured by Shin-Etsu Chemical Co., Ltd., "KF-6017", HLB: 4.5, viscosity at 25°C: 490 mPa·s) • Polyether-modified silicone 2 (PEG-11 methyl ether dimethicone, manufactured by Shin-Etsu Chemical Co., Ltd., "KF-6011", HLB: 14.5, viscosity at 25°C: 130 mPa·s) • Polyether-modified silicone 3 (Lauryl PEG-9 polydimethylsiloxyethyl dimethicone, manufactured by Shin-Etsu Chemical Co., Ltd., "KF-6038", HLB: 3.0, viscosity at 25°C: 550 mPa·s) • Polyglycerin-modified silicone 1 (polyglyceryl-3 polydimethylsiloxyethyl dimethicone, manufactured by Shin-Etsu Chemical Co., Ltd., "KF-6104", viscosity at 25°C: 3300 mPa·s) Branched polyglycerol-modified silicone 1 (bis(polyglyceryl-3 oxyphenylpropyl) dimethicone, manufactured by Kao Corporation as "Sofcare GS-G", viscosity at 25°C: 77000 mPa·s) • Alkyl glyceryl ether-modified silicone 1 (bisalkyl(C16-18) glyceryl undecyl dimethicone, manufactured by Kao Corporation in "Sofcare RS-U", viscosity at 25°C: 6200 mPa·s) • Cationized hydroxyethylcellulose 1 (Polyquaternium-10, manufactured by Kao Corporation as "Poise C-150L", Mw: 1,500,000) • Cationic vinyl polymer 1 (acrylamide / DMAPA acrylate / methoxyPEG methacrylate copolymer, manufactured according to Manufacturing Example 1 below) • Hexadimethrin bromide (HCS160M5, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., Mw: 5,000~10,000)

[0096] Manufacturing Example 1 A four-necked flask equipped with a reflux condenser, liquid delivery device, thermometer, nitrogen gas inlet tube, and stirrer was heated to 50°C in an oil bath. 100 parts by mass of monomer (monomer mass ratio: N-tert-butylacrylamide / N,N-dimethylacrylamide / methoxypolyethylene glycol monomethacrylate / N-(3-dimethylaminopropyl)acrylamide = 55 / 23 / 20 / 2) was dissolved in 75 parts by mass of ethanol to obtain a monomer solution. In addition, 0.2 mol% of initiator (V-65B) relative to the monomer was dissolved in ethanol to a concentration of 5% by mass to obtain an initiator solution. The obtained monomer solution and initiator solution were simultaneously added dropwise to the flask under a nitrogen atmosphere over 130 minutes, and the reaction was carried out by maintaining the temperature at 50°C for 130 minutes, and then at 80°C for a further 120 minutes. After polymerization, the ethanol solution of the polymer was poured into n-hexane for reprecipitation and purification, and vacuum-dried at 80°C to obtain a solid cationic vinyl polymer 1. (Reagents used) • N-tert-butylacrylamide (manufactured by Shinryo Co., Ltd.) • N,N-dimethylacrylamide (manufactured by KJ Chemicals Co., Ltd.) • Methoxypolyethylene glycol monomethacrylate (average number of moles of ethylene oxide added: 9 (manufactured by Shin-Nakamura Chemical Industry Co., Ltd., NK Ester M-90G)) • N-(3-dimethylaminopropyl)acrylamide (manufactured by KJ Chemicals Co., Ltd.) • V-65B: 2,2'-Azobis-(2,4-dimethylvaleronitrile) (manufactured by Fujifilm Wako Pure Chemical Corporation) • Ethanol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) n-Hexane (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)

[0097] From the table above, it can be seen that the surface-coated inorganic particles of the examples exhibit excellent smoothness, lack of squeaking, and durability of feel, resulting in a good tactile experience. Furthermore, the surface-coated inorganic particles of the examples comprise inorganic particles that are not synthetic polymer microparticles as core particles, and the surface treatment agent does not contain synthetic polymers that are solid at 25°C and are not water-soluble. Therefore, they are environmentally friendly and suitable as an alternative material to synthetic polymer microparticles.

[0098] [Manufacture of surface-coated inorganic particles] Example 20 In a 300 mL separable flask, add 1.9 g of polyether-modified silicone 1 (PEG-10 dimethicone, Shin-Etsu Chemical Co., Ltd. "KF-6017", HLB: 4.5, viscosity at 25°C: 490 mPa·s) as a surface treatment agent, and silica 3 (porous silica particles, AGC SI-TEC Inc. "Sunsphere H-32") as inorganic particles, with a medium volume particle size (D 50 ): 3 μm, pore volume: 2 mL / g, specific surface area: 700 m² 2 30 g (spherical) and 94 g of ethanol were added, and the mixture was stirred for 10 minutes at room temperature using a four-bladed inclined paddle blade at a tip speed of 0.79 m / s to obtain a solution and dispersion of the surface treatment agent and inorganic particles. In a separately prepared 300 mL beaker, add an aqueous dispersion of nanosilica 1 (colloidal silica, manufactured by Nissan Chemical Corporation "ST-S", with a medium volume particle size (D 50 ):17g of (9nm) was added, and a small amount of 10% by mass aqueous sulfuric acid solution was added until the pH became 7. Then 51g of deionized water was added, and the mixture was stirred at 600 rpm for 5 minutes at room temperature using a magnetic stirrer to obtain a fine particle dispersion. The aforementioned surface treatment agent and inorganic particle dissolution / dispersion solution was mixed with the aforementioned fine particle dispersion solution, and the mixture was stirred for 15 minutes at room temperature using a four-blade inclined paddle at a tip speed of 0.79 m / s. The resulting mixture was separated into particles (dispersed phase) and solution (dispersion medium) by centrifugation at 3000 rpm for 30 minutes using a HITACHI CR21G III centrifuge. After removing the supernatant, the precipitate was dried under reduced pressure at 50°C for 15 hours to obtain surface-coated inorganic particles. The obtained surface-coated inorganic particles were evaluated. The results are shown in the table below.

[0099] Example 21 In Example 20, surface-coated inorganic particles were obtained using the same method as in Example 20, except that the amount of the nanosilica 1 aqueous dispersion was changed to 68 g and the amount of ion-exchanged water was changed to 15 g. Each of the obtained surface-coated inorganic particles was evaluated. The results are shown in the table below.

[0100] [Table 6]

[0101] The components listed in Table 6 are as follows:

[0102] (Inorganic particles) • Silica 3 (porous silica particles, "Sunsphere H-32" manufactured by AGC SI-TEC Co., Ltd., medium volume particle size (D 50 ): 3 μm, pore volume: 2 mL / g, specific surface area: 700 m² 2 / g, spherical) (Surface treatment agent) • Polyether-modified silicone 1 (PEG-10 dimethicone, manufactured by Shin-Etsu Chemical Co., Ltd., "KF-6017", HLB: 4.5, viscosity at 25°C: 490 mPa·s) (fine particles) • Nanosilica 1 (Colloidal silica (aqueous dispersion of nanosilica), manufactured by Nissan Chemical Corporation, "ST-S", medium volume particle size (D 50 ):9nm) [Industrial applicability]

[0103] According to one embodiment of the present invention, it is possible to provide surface-coated inorganic particles, a surface modifier, and a cosmetic product that have a good feel and are suitable as a substitute material for synthetic polymer fine particles, as well as a surface modification method using the surface-coated inorganic particles, the surface modifier, or the cosmetic product. Furthermore, according to one embodiment of the present invention, it is possible to provide a method for producing surface-coated inorganic particles that have a good feel and are suitable as an alternative material to synthetic polymer fine particles.

Claims

1. Surface-coated inorganic particles in which a part or all of the surface of inorganic particles (A) is coated with a surface treatment agent (B), The inorganic particles (A) include silica particles or mica particles, the surface treatment agent (B) contains at least one selected from a modified silicone (b1) and a water-soluble cationic polymer (b2) that are liquid at 25°C, surface-coated inorganic particles, wherein the modified silicone (b1) comprises at least one selected from polyether-modified silicones, polyglycerin-modified silicones, branched polyglycerol-modified silicones, and alkyl glyceryl ether-modified silicones, and the amount of the surface treatment agent (B) adsorbed to the inorganic particles (A) is 0.1 parts by mass or more per 100 parts by mass of the inorganic particles (A).

2. 2. The surface-coated inorganic particles according to claim 1, wherein the amount of the surface treatment agent (B) adsorbed to the inorganic particles (A) is 0.1 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the inorganic particles (A).

3. 2. The surface-coated inorganic particles according to claim 1, wherein the surface treatment agent (B) contains 50% by mass or more of at least one selected from the modified silicone (b1) and the water-soluble cationic polymer (b2).

4. 2. The surface-coated inorganic particles according to claim 1, wherein the water-soluble cationic polymer (b2) comprises at least one selected from the group consisting of cationic polymers having a cellulose skeleton, cationic vinyl polymers, and chitin-chitosans.

5. 2. The surface-coated inorganic particles according to claim 1, wherein the inorganic particles (A) have a volume median particle size (D50) of 1 μm or more and 30 μm or less.

6. 2. The surface-coated inorganic particles according to claim 1, wherein the volume median particle diameter (D50) of the surface-coated inorganic particles is more than 1 μm and not more than 30 μm.

7. 2. The surface-coated inorganic particles according to claim 1, wherein the content of the synthetic polymer that is solid at 25°C and water-insoluble in the surface-coated inorganic particles is less than 1 mass %.

8. Surface-coated inorganic particles in which a part or all of the surface of inorganic particles (A) is coated with a surface treatment agent (B), The inorganic particles (A) include silica particles or mica particles, the surface treatment agent (B) contains at least one selected from a modified silicone (b1) and a water-soluble cationic polymer (b2) that are liquid at 25°C, the modified silicone (b1) comprises at least one selected from polyether-modified silicones, polyglycerin-modified silicones, branched polyglycerol-modified silicones, and alkyl glyceryl ether-modified silicones, The polyether-modified silicone is at least one selected from the group consisting of PEG-3 dimethicone, PEG-9 dimethicone, PEG-9 methyl ether dimethicone, PEG-10 dimethicone, PEG-11 methyl ether dimethicone, PEG-12 dimethicone, PEG / PPG-20 / 22 butyl ether dimethicone, PEG-32 methyl ether dimethicone, PEG-9 polydimethylsiloxyethyl dimethicone, lauryl PEG-9 polydimethylsiloxyethyl dimethicone, cetyl PEG / PPG-10 / 1 dimethicone, PEG / PPG-30 / 10 dimethicone, and linear polyether-modified silicones in which dimethyl silicone units and polyether units are alternately copolymerized; the polyglycerin-modified silicone is at least one selected from the group consisting of polyglyceryl-3 disiloxane dimethicone, polyglyceryl-3 polydimethylsiloxyethyl dimethicone, and lauryl polyglyceryl-3 polydimethylsiloxyethyl dimethicone; The branched polyglycerol-modified silicone is a compound represented by the following formula (1), which has a structure in which branched polyglycerol chains are bonded to both ends of a dimethylpolysiloxane via linking groups containing oxyphenylene groups: the water-soluble cationic polymer (b2) comprises at least one selected from a cationic polymer having a cellulose skeleton and a cationic vinyl polymer, The surface-coated inorganic particles, wherein the amount of the surface treatment agent (B) adsorbed to the inorganic particles (A) is 2.5 parts by mass or more and 8 parts by mass or less per 100 parts by mass of the inorganic particles (A). 【Chemical 1】 In formula (1), R 12 each independently represents a branched polyglycerol chain, and R 12 includes a branched polyglycerol chain represented by the following formula (3) or (4), and m represents an integer of 0 or more and 10,000 or less. 【Chemistry 2】

9. Surface-coated inorganic particles according to claim 1 or 8, wherein the modified silicone (b1) comprises at least one selected from polyether-modified silicone, polyglycerin-modified silicone, branched polyglycerol-modified silicone and alkyl glyceryl ether-modified silicone, each having a viscosity of 130 mPa·s or more and 77,000 mPa·s or less.

10. Surface-coated inorganic particles according to claim 1 or 8, wherein the surface treatment agent (B) is polyether-modified silicone.

11. 9. The surface-coated inorganic particles according to claim 1, wherein the surfaces of the inorganic particles (A) are partially or entirely coated with fine particles (C).

12. A surface modifier comprising the surface-coated inorganic particles according to claim 1 or 8.

13. A cosmetic product comprising the surface-coated inorganic particles according to claim 1 or 8.

14. The cosmetic product according to claim 13, wherein the content of the synthetic polymer microparticles in the cosmetic product is less than 0.01% by mass.

15. A surface modification method comprising the step of applying the surface-coated inorganic particles according to claim 1 to a target surface.

16. The surface modification method of claim 15, wherein the target surface is skin.

17. 9. The method for producing surface-coated inorganic particles according to claim 1, further comprising the step of mixing the inorganic particles (A) with a surface treatment agent solution containing the surface treatment agent (B) and a solvent.

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