Aqueous silicone dispersion, coating film, and cosmetic

Abstract

An aqueous silicone dispersion liquid, which is an aqueous silicone dispersion liquid that forms an elastomer coating film by normal temperature drying, comprises: (A) an organopolysiloxane elastomer that is an addition reaction product of an alkenyl-containing organopolysiloxane (A-1) having two or more alkenyl groups in one molecule, an organopolysiloxane (A-2) having three or more hydrosilyl groups in one molecule, and a linear diorganopolysiloxane (A-3) having a hydrosilyl group at both molecular chain terminals; (B) an anionic surfactant; (C) a nonionic surfactant; (D) colloidal silica; and (E) water.

Description

Technical Field

[0001] This invention relates to aqueous dispersions, films, and cosmetics that form elastomeric films by drying at room temperature. Background Technology

[0002] Aqueous organosilicon dispersions that form an elastomeric film upon drying are currently composed of various components and are used as fiber treatment agents, rubber coating agents, building material coating agents, paper and plastic film coating agents, or additives thereof, to impart slip properties, water resistance, and peelability.

[0003] One method for forming an elastomeric film is to simultaneously perform a condensation reaction of organosilicon during drying. Examples of compositions for this method include: U.S. Patent No. 3,098,833 (Patent Document 1), which comprises a hydroxylated diorganopolysiloxane, a polysiloxane having hydrogen atoms bonded to silicon, and a curing catalyst in an emulsion composition; Japanese Patent Publication No. 38-860 (Patent Document 2), which comprises a polydiorganosiloxane, a polyorganohydrosiloxane, a polyalkyl silicate ester, and a tin salt of a fatty acid, all with hydroxyl-terminated ends of the molecular chain; Japanese Patent Application Publication No. 53-130,752 (Patent Document 3), which comprises a polydiorganosiloxane with hydroxyl-terminated ends of the molecular chain, a silane having at least three hydrolyzable groups, and a curing catalyst in an emulsion composition; and U.S. Patent No. 3,294,725 (Patent Document 4). Emulsion compositions containing hydroxylated organopolysiloxanes, trialkoxysilanes, and colloidal silica; and organopolysiloxane latex compositions obtained by emulsion polymerization of cyclic organosiloxanes and organotrikoxysilanes, as disclosed in Japanese Patent Application Publication No. 54-131661 (Patent Document 5). However, when these compositions are dried and an elastomer film is formed through the condensation reaction of organosilicon, heating to 100–300°C is generally used. If dried at room temperature, the reaction rate is slow or the reaction does not occur. Furthermore, because they cannot be heated on the skin, they are unsuitable materials for cosmetics.

[0004] Japanese Patent Application Publication No. 7-196984 (Patent Document 6) discloses an organosilicon emulsion composition formed by mixing and dispersing an emulsion of an amino-containing organopolysiloxane with a hydrolyzable silane containing an epoxy group, or an organosilicon emulsion composition formed by mixing and dispersing an emulsion of an epoxy-containing organopolysiloxane with a hydrolyzable silane containing an amino group. The reaction between amino and epoxy groups is rapid. There are concerns about the safety of amino and epoxy groups, especially in cosmetics such as makeup and skincare products that are applied to the skin and maintain a cosmetic film on the skin for a long time.

[0005] There are methods for forming a silicone elastomer film by simultaneously utilizing the addition reaction of alkenylsilane and hydrosilane during drying. Examples of such compositions include an emulsion comprising a vinyl-terminated polydiorganosiloxane, a polyorganohydrosiloxane, and a platinum catalyst, as described in Japanese Patent Application Publication No. 50-94082 (Patent Document 7); and an emulsion comprising a polydiorganosiloxane containing vinyl groups at the molecular chain ends or on the side chains, a polysiloxane having hydrogen atoms bonded to silicon, colloidal silica, and a platinum catalyst. However, in these compositions, if the hydrosilane-containing siloxane is coexisted with the platinum catalyst, the reaction proceeds over time or produces hydrogen gas; therefore, the silicone emulsion and the platinum catalyst must be mixed before use. For general consumers using cosmetics, mixing the liquids before use is inconvenient.

[0006] Japanese Patent Application Publication No. 56-36546 (Patent Document 9) discloses a method for preparing a crosslinked silicone elastomer emulsion by adding a platinum catalyst to an emulsion comprising polydiorganosiloxane and polyorganohydrosiloxane whose molecular chains are capped with vinyl groups, or a method for further incorporating colloidal silica into the emulsion of the silicone elastomer. However, in the case of this composition, although the addition reaction between vinyl silyl and hydrosilyl groups is completed, an elastomer film is formed by drying. However, this film has disadvantages such as lack of elongation and brittleness.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: U.S. Patent No. 3098833

[0010] Patent Document 2: Japanese Patent Publication No. 38-860

[0011] Patent Document 3: Japanese Patent Application Publication No. 53-130752

[0012] Patent Document 4: U.S. Patent No. 3294725

[0013] Patent Document 5: Japanese Patent Application Publication No. 54-131661

[0014] Patent Document 6: Japanese Patent Application Publication No. 7-196984

[0015] Patent Document 7: Japanese Patent Application Publication No. 50-94082

[0016] Patent Document 8: Japanese Patent Application Publication No. 54-52160

[0017] Patent Document 9: Japanese Patent Application Publication No. 56-36546 Summary of the Invention

[0018] The problem that the invention aims to solve

[0019] The present invention was made in view of the above-mentioned actual situation, and its purpose is to provide an aqueous silicone dispersion, a film, and a cosmetic that can be rapidly formed into a film of silicone elastomer with elongation and strength by drying at room temperature.

[0020] Methods for solving problems

[0021] In order to achieve the above-mentioned objective, the inventors conducted in-depth research and found that by making the organosilicon into an organosilicon elastomer obtained by adding a specific alkenyl-containing organopolysiloxane to a specific silyl-containing organopolysiloxane, by including the silyl-containing organopolysiloxane in a linear diorganopolysiloxane with silyl groups at both ends of the molecular chain, and by making the emulsifier in the dispersion an anionic surfactant, thereby reducing its amount, the above-mentioned objective can be achieved.

[0022] Therefore, the present invention provides the following aqueous organosilicon dispersion, coating and cosmetic.

[0023] [1]. An aqueous organosilicon dispersion containing the following (A) organosilicon elastomer is an aqueous organosilicon dispersion that forms an elastomer film by drying at room temperature, comprising:

[0024] (A) An organosilicon elastomer, which is the product of an addition reaction of an alkenyl-containing organopolysiloxane (A-1) having two or more alkenyl groups in one molecule, an organohydrosilane (A-2) having three or more hydrosilyl groups in one molecule, and a linear diorganohydrosilane (A-3) having hydrosilyl groups at both ends of the molecular chain.

[0025] (B) Anionic surfactant: 0.1–5 parts by weight relative to 100 parts by weight of component (A),

[0026] (C) Nonionic surfactant: 0-2 parts by weight relative to 100 parts by weight of component (A),

[0027] (D) Colloidal silica: 0–35 parts by mass relative to 100 parts by mass of component (A), and

[0028] (E) Water: 15 to 200 parts by mass relative to the total of 100 parts by mass of components (A) and (D).

[0029] [2].[1] The aqueous organosilicon dispersion wherein the Asker C rubber of the 1 mm thick elastomer sheet, which is the 25°C dried product of the aqueous organosilicon dispersion, has a hardness (test method specified in the Japan Rubber Industry Association Standard Specification (SRIS)) of 5 or higher.

[0030] [3]. [1] or [2] The aqueous organosilicon dispersion wherein the dumbbell-shaped No. 3 test piece of the 1 mm thick elastomer sheet of the aqueous organosilicon dispersion dried at 25°C has an elongation at break (test method specified in JIS K 6251) of 20% or more and a tensile strength at break (test method specified in JIS K 6251) of 0.05 MPa or more.

[0031] [4]. The aqueous organosilicon dispersion described in any one of [1] to [3], wherein component (A) is the product of the addition reaction of components (A-2) and (A-3) with a mass ratio (A-2):(A-3) of 5:95 to 90:10.

[0032] [5]. An elastomer film obtained by drying the aqueous organosilicon dispersion described in any one of [1] to [4] at room temperature.

[0033] [6]. Cosmetic material, comprising any one of the aqueous organosilicon dispersions described in [1] to [4].

[0034] [7].[6] The cosmetic material mentioned is selected from makeup cosmetic materials, skin care cosmetic materials and eyelash cosmetic materials.

[0035] The effects of the invention

[0036] According to the present invention, an aqueous organosilicon dispersion is obtained which can rapidly form a film of organosilicon elastomer with elongation and strength by drying at room temperature. This aqueous organosilicon dispersion is particularly useful for cosmetics such as makeup products, skin care products, and eyelash products. Detailed Implementation

[0037] The present invention will now be described in detail.

[0038] [(A) ingredient]

[0039] (A) The organosilicon elastomer is a product of the addition reaction between an alkenyl-containing organopolysiloxane and a silyl-containing organopolysiloxane. The alkenyl-containing organopolysiloxane is an alkenyl-containing organopolysiloxane having two or more alkenyl groups in one molecule (A-1), the silyl-containing organopolysiloxane is an organopolysiloxane having three or more silyl groups in one molecule (A-2), and a linear diorganopolysiloxane with silyl groups at both ends of the molecular chain (A-3).

[0040] (A-1)

[0041] As an alkenyl-containing organopolysiloxane having two or more alkenyl groups in one molecule, it is possible to use one alone or to use two or more in appropriate combination. For example, an example can be listed with the following average composition formula (1).

[0042] R 1 a R 2 b SiO (4-a-b) / 2 (1)

[0043] (In the formula, R in the formula) 1 Independently, R is a monovalent hydrocarbon group with 1 to 30 carbon atoms, excluding alkenyl groups, and either substituted or unsubstituted. 2 Alkenyl groups are independently composed of 2 to 6 carbon atoms. a and b are positive numbers satisfying 0 < a < 3, 0 < b ≤ 3, and 0.1 ≤ a + b ≤ 3, preferably positive numbers satisfying 0 < a ≤ 2.295, 0.005 ≤ b ≤ 2.3, and 0.5 ≤ a + b ≤ 2.3.

[0044] This refers to organopolysiloxanes containing alkenyl groups.

[0045] As R 1 Examples include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, decyl, undecyl, dodecyl, tetradecyl, pentadecyl, hexadecyl, heptadecanyl, octadecyl, nonadecanyl, eicosyl, dodecyl, tridecyl, tetradecyl, triacontyl, triacontyl, phenyl, tolyl, naphthyl, etc.; aralkyl groups such as benzyl, phenethyl, etc.; cycloalkyl groups such as cyclopentyl, cyclohexyl, cycloheptyl, etc.; and hydrocarbon groups in which some or all of the hydrogen atoms bonded to the carbon atom of these groups are replaced by halogen atoms (fluorine, chlorine, bromine, iodine, etc.), hydrocarbon groups in which acryloyloxy, methacryloyloxy, epoxy, glycidyloxy, carboxyl, etc. are replaced, and hydrocarbon groups in which the above atoms and substituents are replaced. Among these, all R groups are preferred in industry. 1 More than 50 mol% of the radical is methyl.

[0046] As R 2 Examples of vinyl, allyl, propenyl, butenyl, pentenyl, and hexenyl compounds can be listed, with vinyl being the preferred choice in industry.

[0047] Regarding the structure of component (A-1), it can be linear, cyclic, or branched. As a linear structure, an alkenyl-containing organopolysiloxane can be exemplified by an alkenyl-containing organopolysiloxane represented by the following general formula (2).

[0048] [Chemistry 1]

[0049]

[0050] (where R is in the formula) 1 R 2 Similar to the above, c is a positive number, d is 0 or a positive number, and e is 0 or 1. However, d and e are numbers that satisfy d + 2 × e ≥ 2.

[0051] As a branching structure, examples of using R can be listed. 1 SiO 3 / 2 The unit branch of the organopolysiloxane containing alkenyl groups is represented by the following general formula (3).

[0052] [Chemistry 2]

[0053]

[0054] (where R is in the formula) 1 R 2 Similar to the above, f is a positive number, g is 0 or a positive number, h is a positive number, i is a positive number, j is 0 or a positive number, k is 0 or 1, and l is 0 or 1. However, g, j, k, and l are numbers that satisfy g + h × j + 2 × k + h × l ≥ 2.

[0055] As a utilization of SiO 4 / 2 The structure of the unit branch, for example, can be represented by the following general formula (4) containing an alkenyl group of organopolysiloxane.

[0056] [Chemistry 3]

[0057]

[0058] (where R is in the formula) 1 R 2 Similar to the above, m is a positive number, n is 0 or a positive number, o is a positive number, p is a positive number, q is 0 or a positive number, r is 0 or 1, and s is 0 or 1. However, n, q, r, and s are numbers that satisfy n + 2 × o × q + 2 × r + 2 × o × s ≥ 2.

[0059] In addition, examples can be given of alkenyl-containing organopolysiloxanes represented by the following unit formula (5) that have two or more alkenyl groups in one molecule.

[0060] [R 1 3SiO 1 / 2 ] t [R 2 (R 1 )2SiO 1 / 2 ] u [SiO 4 / 2 ] v (5)

[0061] (where R is in the formula) 1 R 2 As above, t is 0 or a positive number, u is a positive number, and v is a positive number.

[0062] (A-2)

[0063] Organohydrosilanes having three or more hydrosilyl groups in one molecule can be used alone or in appropriate combinations of two or more. For example, an example can be listed with the following average compositional formula (6).

[0064] R 3 w H x SiO (4-w-x) / 2

[0065] (where R is in the formula) 3 Independently, it is a monovalent hydrocarbon group with 1 to 30 carbon atoms, excluding the alkenyl group, and either substituted or unsubstituted. w and x are positive numbers satisfying 0 < w < 3, 0 < x ≤ 3, and 0.1 ≤ w + x ≤ 3, preferably positive numbers satisfying 0 < w ≤ 2.295, 0.005 ≤ x ≤ 2.3, and 0.5 ≤ w + x ≤ 2.3.

[0066] The term represents an organohydrogen polysiloxane. As R 3 , can be instantiated with the above R 1 Same group.

[0067] Regarding the structure of component (A-2), it can be linear, cyclic, or branched. For example, an organohydrogen polysiloxane with a linear structure can be represented by the following general formula (7).

[0068] [Chemistry 4]

[0069]

[0070] (where R is in the formula) 3 Similar to the above, y is a positive number, z is a positive number, and a1 is 0 or 1. However, z and a1 are numbers that satisfy z + 2 × a1 ≥ 3.

[0071] As a branching structure, for example, the use of R can be listed. 3 SiO 3 / 2 The branching structure of unit branches is represented by the following general formula.

[0072] [Chemistry 5]

[0073]

[0074] (where R is in the formula) 3 Similar to the above, b1 is a positive number, c1 is 0 or a positive number, d1 is a positive number, e1 is a positive number, f1 is 0 or a positive number, g1 is 0 or 1, and h1 is 0 or 1. However, c1, f1, g1, and h1 are numbers that satisfy c1 + d1 × f1 + 2 × g1 + d1 × h1 ≥ 3.

[0075] As a utilization of SiO 4 / 2 The structure of unit branches can be exemplified by structures represented by the following general formula.

[0076] [Chemistry 6]

[0077]

[0078] (where R is in the formula) 3 Similar to the above, i1 is a positive number, j1 is 0 or a positive number, k1 is a positive number, L1 is a positive number, m1 is 0 or a positive number, n1 is 0 or 1, and o1 is 0 or 1. However, j1, m1, n1, and o1 are numbers that satisfy j1 + 2 × k1 × m1 + 2 × n1 + 2 × k1 × o1 ≥ 3.

[0079] In addition, examples can be given of organohydrosiloxanes represented by the following unit formula (10) that have more than three hydroxysilyl groups in one molecule.

[0080] [R 3 3SiO 1 / 2 ] p1 [H(R 3 )2SiO 1 / 2 ] q1 [SiO 4 / 2 ] r1 (10)

[0081] (where R is in the formula) 3 As above, p1 is 0 or a positive number, q1 is a positive number, and r1 is a positive number.

[0082] (A-3)

[0083] As a linear diorganohydrogen polysiloxane having silyl groups at both ends of the molecular chain, one type can be used alone or in appropriate combinations of two or more types. For example, a diorganohydrogen polysiloxane with two silyl groups in one molecule can be listed, specifically, a diorganohydrogen polysiloxane of the following general formula (11).

[0084] [Chemistry 7]

[0085]

[0086] (R in the formula) 4 Independently, it is a monovalent hydrocarbon group with 1 to 30 carbon atoms, excluding the alkenyl group, and either substituted or unsubstituted. s1 is a positive number from 5 to 1000, preferably a positive number from 10 to 500.

[0087] Furthermore, as R 4 , can be instantiated with R 1 Same group.

[0088] For the (A-1) component, which contains an alkenyl group, and the (A-2) component, which contains three or more hydroxyl groups in one molecule, there is no particular limitation on viscosity, and solid substances may also be included. The kinematic viscosity at 25°C for the (A-3) component, which is a linear di-organohydrosiloxane containing hydroxyl groups at both ends of the molecular chain, is preferably 10,000 mm⁻¹. 2 / s or less, more preferably 1000mm 2 Below / s. There is no specific limitation on the lower limit; it can be set to 5mm. 2 The kinematic viscosity of the mixed solution of components (A-1), (A-2), and (A-3) is preferably 10,000 mm³ / s or higher at 25°C. 2 / s or less, more preferably 1000mm 2 Below / s. There is no specific limitation on the lower limit; it can be set to 5mm. 2 / s or higher. If the kinematic viscosity exceeds 10000 mm. 2 / s, in the manufacturing method described later, reducing the particle size may become difficult. It should be noted that in this invention, the kinematic viscosity is a value measured at 25°C using an Orthocriteus viscometer.

[0089] Regarding the mass ratio of the alkenyl-containing organopolysiloxane of component (A-1), the organohydrosilane having three or more hydrosilyl groups in one molecule of component (A-2), and the linear diorganohydrosilane containing hydrosilyl groups at both ends of the molecular chain of component (A-3), it is preferable that the total number of moles of hydrosilyl groups of components (A-2) and (A-3) is in the range of 0.5 to 2.0 relative to 1 mole of alkenyl groups of component (A-1), more preferably in the range of 0.8 to 1.5.

[0090] Regarding the mass ratio of organohydrogen polysiloxane (A-2) having three or more hydrosilyl groups per molecule to linear diorganohydrogen polysiloxane (A-3) containing hydrosilyl groups at both ends of its molecular chain, if the ratio of (A-3) is excessively reduced, the resulting coating may become brittle with no elongation; if the ratio of (A-3) is excessively increased, no coating may form, and the film may become a gel or liquid. From a ratio perspective, the mass ratio (A-2):(A-3) of (A-2) to (A-3) cannot be generalized, but a range of 5:95 to 90:10 is preferred, and a range of 10:90 to 80:20 is more preferred.

[0091] [Platinum Group Metal Catalysts]

[0092] (A) The organosilicon elastomer is a product of the addition reaction between an alkenyl-containing organopolysiloxane and a silane-containing organohydrosiloxane. In this addition reaction between the alkenyl and silane, a known platinum group metal catalyst can be used. Examples include platinum (including platinum black), rhodium, palladium, and other platinum group metals; H₂PtCl₄·k'H₂O, H₂PtCl₆·k'H₂O, NaHPtCl₆·k'H₂O, KHPtCl₆·k'H₂O, Na₂PtCl₆·k'H₂O, K₂PtCl₄·k'H₂O, PtCl₄·k'H₂O, PtCl₂, Na₂HPtCl₄·k'H₂O (where k' is an integer from 0 to 6). Preferred components include platinum chloride, chloroplatinic acid, and chloroplatinate (0 or 6); alcohol-modified chloroplatinic acid (refer to US Patent No. 3,220,972); complexes of platinum chloride, chloroplatinic acid, and olefins (refer to US Patent Nos. 3,159,601, 3,159,662, and 3,775,452); complexes of chloroplatinic acid and vinyl-containing siloxanes; complexes of platinum and vinyl-containing siloxanes; products in which platinum group metals such as platinum black and palladium are supported on alumina, silica, carbon, etc.; rhodium-olefin complexes; trichlorotriphenylphosphine rhodium (Wilkinson catalyst), etc.

[0093] The amount of platinum group metal catalyst can be the effective amount for carrying out the addition reaction. For example, in a platinum-containing catalyst, the mass conversion of platinum in the catalyst relative to the total mass of components (A-1), (A-2), and (A-3) is about 0.1 to 100 ppm (mass), preferably about 0.5 to 50 ppm, and more preferably about 1 to 30 ppm.

[0094] (A) The organosilicon elastomer may contain silicone oil, organosilicon resin, organosilicon, inorganic powder, organic powder, antioxidant, etc.

[0095] (A) The silicone elastomer is a silicone elastomer that is the product of the addition reaction of a specific alkenyl-containing organopolysiloxane (A-1) with specific hydroxysilyl-containing organopolysiloxanes (A-2) and (A-3). The structure of the resulting silicone elastomer is complexly determined by the components (A-1) to (A-3) used and their ratio.

[0096] (A) The component is an addition reaction product of an alkenyl-containing organopolysiloxane and a hydroxyl-containing organohydrosiloxane, which is dispersed in water and therefore in particulate form. Its volume average particle size is preferably 10 μm or less, more preferably 1 μm or less. There is no particular limitation on the lower limit, and it can also be set to 0.1 μm or more. If the volume average particle size is larger than 10 μm, the formed film will have no elongation and become brittle. It should be noted that in this invention, the volume average particle size is a measured value obtained using a laser diffraction / scattering particle size determination method (apparatus).

[0097] [(B) Component]

[0098] In this invention, the anionic surfactant of component (B) functions as a dispersant for the organosilicon elastomer of component (A) in an aqueous organosilicon dispersion. On the other hand, it also functions as an emulsifier in the emulsification of an alkenyl-containing organopolysiloxane and a hydrosilyl-containing organohydropolysiloxane, which are raw materials for component (A), as described later. The anionic surfactant can be used alone or in a suitable combination of two or more.

[0099] Examples of anionic surfactants include alkyl sulfate salts such as sodium dodecyl sulfate, polyoxyethylene alkyl ether sulfate salts, polyoxyethylene alkylphenyl ether sulfate salts, sulfate salts of fatty acid alkylolamides, alkylbenzene sulfonates, polyoxyethylene alkylphenyl ether sulfonates, α-olefin sulfonates, α-sulfonyl fatty acid esters, alkylnaphthalene sulfonic acids, alkyl diphenyl ether disulfonates, alkane sulfonates, N-acyl taurate, dialkyl sulfosuccinate, monoalkyl sulfosuccinate, polyoxyethylene alkyl ether sulfosuccinate, fatty acid salts, polyoxyethylene alkyl ether carboxylates, N-acyl amino acid salts, monoalkyl phosphate salts, dialkyl phosphate salts, and polyoxyethylene alkyl ether phosphate salts. Alkyl sulfate salts are preferred from the perspective of elongation and tensile strength of the elastomer coating.

[0100] Regarding the amount of component (B), it is 0.1 to 5 parts by mass relative to 100 parts by mass of the silicone elastomer in component (A), preferably 0.5 to 2 parts by mass. If it is more than 5 parts by mass, the resulting film will have no elongation and become brittle; if it is less than 0.1 parts by mass, the particle size will become larger or it will no longer be able to emulsify during the emulsification of the raw material of component (A) as described later.

[0101] [(C) Component]

[0102] In this invention, the nonionic surfactant of component (C) functions as a dispersant for the organosilicon elastomer of component (A) in the aqueous organosilicon dispersion. On the other hand, it is also an emulsifier and a dispersant for platinum group metal catalysts in the emulsification of the alkenyl-containing organopolysiloxane and the organopolysiloxane having hydroxymethyl silyl groups, which are raw materials of component (A) as described later.

[0103] Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyethylene glycol fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, polyoxyethylene glycerol fatty acid esters, polyglycerol fatty acid esters, propylene glycol fatty acid esters, polyoxyethylene castor oil, polyoxyethylene hardened castor oil, polyoxyethylene hardened castor oil fatty acid esters, polyoxyethylene alkylamines, polyoxyethylene fatty acid amides, polyoxyethylene modified organopolysiloxanes, and polyoxyethylene polyoxypropylene modified organopolysiloxanes. Nonionic surfactants can be used alone or in combination of two or more. When using two or more in combination, nonionic surfactants that do not contain polyethers, such as sorbitan fatty acid esters and glycerol fatty acid esters, can also be used in combination.

[0104] It should be noted that the nonionic surfactant in this invention is any component, but since it reduces film-forming properties, a small amount of nonionic surfactant is preferred. Regarding the amount of component (C), it is 0 to 2 parts by mass relative to 100 parts by mass of the silicone elastomer in component (A), preferably 0 to 1 part by mass, and more preferably 0 to 0.5 parts by mass.

[0105] [(D) component]

[0106] In this invention, the colloidal silica of component (D) has the function of improving the elongation and tensile strength of the obtained organosilicon elastomer film. The colloidal silica is nano-sized silica, preferably with a particle size of 10-300 nm, more preferably 10-50 nm. It should be noted that the particle size is determined by observation using a transmission electron microscope.

[0107] In this invention, colloidal silica is used in the form of a silica sol dispersed in water. The concentration of colloidal silica in the aqueous dispersion is not particularly limited, for example, it is 10 to 60% by mass. The pH is not particularly limited, but considering applications such as skin contact, a range of 4 to 10 is preferred.

[0108] It should be noted that in this invention, component (D) is any component, and the amount of component (D) relative to 100 parts by mass of the silicone elastomer of component (A) is 0 to 35 parts by mass, preferably 0 to 25 parts by mass. If it is more than 35 parts by mass, the resulting film will have no elongation and become brittle. In the case of formulation, it can be 5% by mass or more relative to 100 parts by mass of the silicone elastomer of component (A).

[0109] [(E) component]

[0110] In this invention, water (E) serves as the dispersion medium for the silicone elastomer (A) and colloidal silica (D). The amount of component (E) is 15 to 200 parts by mass, preferably 25 to 150 parts by mass, relative to a total of 100 parts by mass of components (A) and (D). If the amount is more than 200 parts by mass, the drying speed slows down, and film formation takes longer; if the amount is less than 15 parts by mass, the viscosity of the aqueous silicone dispersion increases, making manufacturing difficult or difficult to handle.

[0111] [Other ingredients]

[0112] In the aqueous organosilicon dispersion of the present invention, a water-soluble polymer compound may be included for purposes such as improving the dispersibility of component (A). There is no particular limitation on the water-soluble polymer compound; examples include nonionic water-soluble polymer compounds, anionic water-soluble polymer compounds, cationic water-soluble polymer compounds, and biionic water-soluble polymer compounds.

[0113] Examples of nonionic, water-soluble polymers include copolymers of vinyl alcohol and vinyl acetate, polymers of acrylamide, polymers of vinylpyrrolidone, copolymers of vinylpyrrolidone and vinyl acetate, polyethylene glycol, polymers of isopropylacrylamide, polymers of methyl vinyl ether, starch, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, guar gum, xanthan gum, etc.

[0114] Examples of anionic, water-soluble polymers include polymers of sodium acrylate, copolymers of sodium acrylate and sodium maleate, copolymers of sodium acrylate and acrylamide, polymers of sodium styrene sulfonate, copolymers of sodium polyisoprene sulfonate and styrene, polymers of sodium naphthalene sulfonate, carboxymethyl starch, phosphate starch, carboxymethyl cellulose, sodium alginate, gum arabic, carrageenan, sodium chondroitin sulfate, and sodium hyaluronate.

[0115] Examples of cationic water-soluble polymers include polymers of dimethyl diallyl ammonium chloride, polymers of vinylimidazoline, polymers of methyl vinylimidazoline chloride, polymers of ethyl acrylate trimethyl ammonium chloride, polymers of ethyl methacrylate trimethyl ammonium chloride, polymers of acrylamide propyltrimethyl ammonium chloride, polymers of methacrylamide propyltrimethyl ammonium chloride, epichlorohydrin / dimethylamine polymers, polymers of ethyleneimine, quaternary compounds of ethyleneimine polymers, polymers of allylamine hydrochloride, polylysine, cationic starch, cationic cellulose, chitosan, and their derivatives obtained by copolymerizing them with monomers having nonionic or anionic groups.

[0116] Examples of diionic water-soluble polymers include copolymers of ethyl methacrylate trimethylammonium chloride and acrylic acid and acrylamide, copolymers of ethyl methacrylate trimethylammonium chloride and acrylic acid and acrylamide, and Hoffmann decomposition products of acrylamide polymers.

[0117] The aqueous organosilicon dispersion of the present invention may contain antibacterial and preservative agents and antimicrobial agents. Examples of antibacterial and preservative agents include alkyl p-hydroxybenzoate, benzoic acid, sodium benzoate, sorbic acid, potassium sorbate, phenoxyethanol, etc. Examples of antimicrobial agents include benzoic acid, salicylic acid, carbolic acid, sorbic acid, alkyl p-hydroxybenzoate, p-chloro-m-cresol, hexachlorophenol, benzalkonium chloride, chlorhexidine, trichlorocarbonyl aniline, photosensitive agent, phenoxyethanol, etc.

[0118] [Manufacturing Method]

[0119] The aqueous organosilicon dispersion of the present invention can be manufactured by emulsifying an alkenyl-containing organopolysiloxane ((A-1)) and a hydroxysilyl-containing organohydropolysiloxane ((A-2) and ((A-3))) as raw materials of component (A) in water of component (E) using an anionic surfactant of component (B), followed by the addition reaction of a platinum group metal catalyst. A nonionic surfactant of component (C) can be used during emulsification.

[0120] Emulsification can be performed using a general emulsifying disperser. Examples of such emulsifying dispersers include high-speed rotary centrifugal radial mixers such as HOMODISPER, high-speed rotary shear mixers such as homogeneous mixers, high-pressure jet emulsifying dispersers such as pressure homogenizers, colloid mills, and ultrasonic emulsifiers.

[0121] When the silicone elastomer of component (A) contains silicone oil, silicone resin, organosilane, inorganic powder, organic powder, and antioxidant, the raw materials of component (A) and them can be mixed in advance.

[0122] The platinum group metal catalyst can be added after the emulsification process as described above, or it can be dissolved in the raw material of component (A) beforehand. When adding the platinum group metal catalyst after the emulsification process, it can be added by dissolving it in a solvent. Alternatively, if the catalyst has poor dispersibility in water, it can be added while dissolved in a nonionic surfactant of component (C). When the platinum group metal catalyst is dissolved in the raw material of component (A) beforehand, it can be added in a way that prevents the addition reaction from occurring until the end of the emulsification process, for example, by cooling to a low temperature below 5°C. The addition reaction can be carried out at room temperature, for example, 20–25°C. If the reaction is not complete, it can be carried out at a temperature below 100°C. There is no particular limitation on the stirring time used for the reaction, which is typically 1–24 hours.

[0123] When colloidal silica is incorporated with component (D), a colloidal silica dispersion using water as the dispersion medium is used, as described above. It is preferable to add it after the emulsification step or after the addition reaction step.

[0124] [Aqueous Organosilicon Dispersion]

[0125] In the aqueous organosilicon dispersion of the present invention, (A) is a silicone elastomer dispersed as the product of an addition reaction between an alkenyl-containing organopolysiloxane (A-1) having two or more alkenyl groups in one molecule, an organohydrosilane (A-2) having three or more hydrosilyl groups in one molecule, and a linear diorganohydrosilane (A-3) having hydrosilyl groups at both ends of its molecular chain. Furthermore, the pH of the dispersion is not particularly limited, but a range of 4 to 10 is preferred for application to the skin. It should be noted that in the present invention, "aqueous" means easily dilute in water.

[0126] [Elastomer Coating]

[0127] The aqueous organosilicon dispersion of the present invention forms an elastomeric film by drying at room temperature. The elastomeric film may be viscous, but is not gel-like. The drying temperature is appropriately selected from 1 to 250°C, and a film can be formed even at room temperature such as 25°C. The drying time is preferably from a few seconds to one week.

[0128] The rubber hardness, elongation at break, and tensile strength at break of the elastomer coating are as follows. If the rubber hardness, elongation at break, or tensile strength is too low, for example, when using an aqueous silicone dispersion in skin care cosmetics, it is considered difficult to peel off the skin as a film; in addition, when used in eyelash cosmetics, it is considered easy to rub off.

[0129] [Manufacturing Method of Elastomer Sheets]

[0130] An aqueous silicone dispersion with a thickness of approximately 1 mm after drying is cast into a polypropylene tray and dried at 25°C for 48 hours to produce an elastomer sheet.

[0131] [Rubber Hardness]

[0132] For elastomer sheets produced using the above method, the rubber hardness of a type A durometer is determined using the method specified in JIS K 6251. If the rubber hardness of the type A durometer is less than 10, the rubber hardness of an Asker C tester is determined using the method specified in the Japan Rubber Industry Association Standard Specification (SRIS). The rubber hardness of the elastomer sheet using the Asker C tester is preferably 5 or higher, more preferably 30 or higher. There is no particular upper limit, and the rubber hardness of the type A durometer can also be made to be 60 or lower.

[0133] [Elongation at fracture, tensile strength at fracture]

[0134] The elongation at break (by the test method specified in JIS K 6251) of the dumbbell-shaped No. 3 test piece of the elastomer sheet is preferably 20% or more, more preferably 50% or more. There is no particular upper limit, and it can also be 1000% or less. The tensile strength at break (by the test method specified in JIS K 6251) of the elastomer sheet is preferably 0.05 MPa or more, more preferably 0.10 MPa or more. There is no particular upper limit, and it can also be 5.0 MPa or less.

[0135] [use]

[0136] The aqueous organosilicon dispersion of the present invention can rapidly form a film of organosilicon elastomer with elongation and strength upon drying at room temperature. In particular, it is free of amino and epoxy groups, so there are no concerns about skin safety. Therefore, it can be incorporated into makeup products such as foundation (including all solid and liquid products), eyeshadow, lipstick, lip gloss, blush, eyebrow pencil, and eyebrow liner, as well as skincare products and eyelash products such as mascara. Furthermore, it can be used as a migration-resistant agent in makeup products, a film-forming agent in skincare products, and a lubrication and volume-enhancing agent in eyelash products. There is no particular limitation on the amount of the aqueous organosilicon dispersion incorporated into the makeup product; it can be appropriately incorporated within the range of 10% to 95% by mass. When used in makeup products, the objects to which the film is formed can be skin, hair, nails, and eyelashes. In addition, other applications include water repellents, waterproofing agents, release agents for paper, water repellents for fiber products, hand feel improvers, water repellents and waterproofing agents for concrete, mortar, and wood, as well as adhesives for coatings containing inorganic particles such as titanium dioxide particles.

[0137] Example

[0138] The following examples and comparative examples illustrate the invention in detail, but the invention is not limited to the examples described below. It should be noted that in the examples below, kinematic viscosity is a value measured using an Auster viscometer at 25°C, and "%" indicating concentration and content represents "mass %".

[0139] It should be noted that "the manufacturing method of elastomer sheets, the rubber hardness, the elongation at break, and the method for determining the tensile strength at break" are described below.

[0140] [Manufacturing Method of Elastomer Sheets]

[0141] An aqueous silicone dispersion with a thickness of approximately 1 mm after drying is cast into a polypropylene tray and dried at 25°C for 48 hours to produce an elastomer sheet.

[0142] Methods for determining rubber hardness

[0143] The elastomer sheet was peeled from the tray, and the rubber hardness was determined using a Type A durometer according to the method specified in JIS K 6251. When the rubber hardness on the Type A durometer was less than 10, the rubber hardness on an Asker C tester was determined using the method specified in the Japan Rubber Industry Association Standard Specification (SRIS).

[0144] [Methods for determining elongation at fracture and tensile strength at fracture]

[0145] The elongation at break and tensile strength at break of dumbbell-shaped No. 3 test specimens were tested using the method specified in JIS K 6251.

[0146] [Example 1]

[0147] The kinematic viscosity of 130 mm, represented by the following formula (A-1'), is... 2 / s, 271g of dimethyl polysiloxane containing vinyl groups at both ends of the molecular chain with a vinyl content of 0.035mol / 100g, and a kinematic viscosity of 430mm, expressed by the following formula (A-2'). 2 / s, 137g of methylhydrosiloxane containing 0.040mol / 100g of silane, and a kinematic viscosity of 35mm as expressed by the following formula (A-3'). 2 92g of a linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain, with a silyl group content of 0.066mol / 100g, was dissolved in a 1-liter glass beaker by stirring at 2000 rpm using a homogeneous mixer. The total number of silyl groups relative to the vinyl group of the vinyl-containing dimethylpolysiloxane of formula (A-1') is 1.22, and the total number of silyl groups in the methylhydropolysiloxane of formula (A-2') and the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain of formula (A-3') is 60:40.

[0148] [Chemistry 8]

[0149]

[0150] Next, 5g of sodium dodecyl sulfate (representing 1.0 part by weight relative to 100 parts by weight of silicone elastomer) and 130g of water were added. The mixture was stirred at 8000 rpm using a homogenizer, resulting in oil-in-water droplets, confirming thickening. Stirring was continued for another 15 minutes. While stirring at 2000 rpm, 353g of water was added to dilute the mixture. The emulsion was then passed through a homogenizer under a pressure of 100 MPa to obtain a homogeneous white emulsion.

[0151] 790 g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device. After adjusting the temperature to 20–25 °C, 0.6 g of a platinum-vinyl-containing siloxane complex isododecane solution (platinum content 0.5%) and 1.1 g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) (0.28 parts by mass relative to 100 parts by mass of silicone elastomer) were added under stirring. The mixture was stirred at this temperature for 12 hours to carry out the addition reaction of vinyl-containing dimethyl polysiloxane of formula (A-1') with methyl hydrosiloxane of formula (A-2') and linear dimethyl hydrosiloxane with silyl groups at both ends of the molecular chain of formula (A-3'). Next, 8 g of phenoxyethanol as an antibacterial agent was added, and the mixture was stirred at this temperature for 10 minutes to obtain an aqueous silicone dispersion. The amount of water in the aqueous organosilicon dispersion is 96.6 parts by mass relative to the total of 100 parts by mass of component (A) above.

[0152] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 900 nm.

[0153] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a viscous sheet. The Asker C rubber had a hardness of 8, an elongation at break of 65%, and a tensile strength at break of 0.08 MPa.

[0154] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0155] [Example 2]

[0156] Add 53 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) (the amount of colloidal silica is 5.3 parts by mass relative to 100 parts by mass of the silicone elastomer) to the aqueous silicone dispersion obtained in the same manner as in Example 1, and stir for 10 minutes to obtain the aqueous silicone dispersion. The amount of water in the aqueous silicone dispersion is 96.9 parts by mass relative to the total 100 parts by mass of the above (A) component and colloidal silica.

[0157] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a viscous sheet. Asker C rubber had a hardness of 26, an elongation at break of 130%, and a tensile strength at break of 0.15 MPa.

[0158] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0159] [Example 3]

[0160] 111 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) was added to the aqueous silicone dispersion obtained in the same manner as in Example 1 (the amount of colloidal silica was 11.1 parts by mass relative to 100 parts by mass of silicone elastomer), and the mixture was stirred for 10 minutes to obtain an aqueous silicone dispersion. The amount of water in the aqueous silicone dispersion was 100.8 parts by mass relative to the total amount of component (A) and colloidal silica.

[0161] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a viscous sheet. The rubber hardness on a Type A hardness tester was 16, the elongation at break was 230%, and the tensile strength at break was 0.36 MPa.

[0162] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0163] [Example 4]

[0164] 177 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) was added to the aqueous silicone dispersion obtained in the same manner as in Example 1 (the amount of colloidal silica was 17.7 parts by mass relative to 100 parts by mass of silicone elastomer), and the mixture was stirred for 10 minutes to obtain the aqueous silicone dispersion. The amount of water in the aqueous silicone dispersion was 103.6 parts by mass relative to the total amount of component (A) and colloidal silica.

[0165] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a non-sticky sheet. The rubber hardness on a Type A hardness tester was 32, the elongation at break was 270%, and the tensile strength at break was 0.81 MPa.

[0166] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0167] [Example 5]

[0168] The kinematic viscosity of 130 mm, represented by the above formula (A-1'), is... 2 / s, 235g of dimethyl polysiloxane containing vinyl groups at both ends of its molecular chain, with a vinyl content of 0.035mol / 100g, and composed of the following unit formula

[0169] [(CH3)3SiO 1 / 2 ] t [CH2=CH(CH3)2SiO 1 / 2 ] u [SiO 4 / 2 ] v

[0170] (In the formula, t:u:v = 36:6:58)

[0171] The expression refers to 25g of a vinyl-containing polysiloxane resin in solid form with a vinyl content of 0.086mol / 100g, and a kinematic viscosity of 430mm as expressed by the above formula (A-2'). 2 / s, 119g of methylhydrosiloxane containing 0.040mol / 100g of silane, and a kinematic viscosity of 35mm as expressed by the above formula (A-3'). 2121g of a linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain, with a silyl group content of 0.066mol / 100g, was dissolved in a 1-liter glass beaker by stirring at 2000 rpm using a homogeneous mixer. The total number of silyl groups in the dimethylhydropolysiloxane containing vinyl groups (A-1') and the linear dimethylhydropolysiloxane containing silyl groups (A-2') and the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain (A-3') is 1.22, relative to the 1 vinyl group in the dimethylhydropolysiloxane containing vinyl groups (A-1'). Furthermore, the mass ratio of the methylhydropolysiloxane containing silyl groups (A-2'):(A-3') is 50:50.

[0172] Next, 5g of sodium dodecyl sulfate (representing 1.0 part by weight relative to 100 parts by weight of silicone elastomer) and 130g of water were added. The mixture was stirred at 8000 rpm using a homogenizer, resulting in oil-in-water droplets, confirming thickening. Stirring was continued for another 15 minutes. While stirring at 2000 rpm, 353g of water was added for dilution. The mixture was then passed through a homogenizer under 100 MPa pressure to obtain a homogeneous white emulsion.

[0173] 790 g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device. After adjusting the temperature to 20–25 °C, 0.6 g of a platinum-vinyl-containing siloxane complex solution of isododecane (platinum content 0.5%) and 1.1 g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) (0.28 parts by mass relative to 100 parts by mass of silicone elastomer) were added under stirring. The mixture was stirred at this temperature for 12 hours to carry out the addition reaction of the vinyl-containing dimethyl polysiloxane of formula (A-1') with the methyl hydrosiloxane of formula (A-2') containing hydrosilyl groups and the linear dimethyl hydrosiloxane of formula (A-3') containing hydrosilyl groups at both ends of the molecular chain. Next, 8 g of phenoxyethanol as an antibacterial agent was added, and the mixture was stirred at this temperature for 10 minutes to obtain an aqueous silicone dispersion. The amount of water in the aqueous organosilicon dispersion is 96.6 parts by mass relative to 100 parts by mass of component (A) above.

[0174] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 780 nm.

[0175] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a viscous sheet. The Asker C rubber had a hardness of 12, an elongation at break of 130%, and a tensile strength at break of 0.14 MPa.

[0176] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0177] [Example 6]

[0178] 177 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) was added to the aqueous silicone dispersion obtained in the same manner as in Example 5 (the amount of colloidal silica was 17.7 parts by mass relative to 100 parts by mass of silicone elastomer), and the mixture was stirred for 10 minutes to obtain the aqueous silicone dispersion. The amount of water in the aqueous silicone dispersion was 103.6 parts by mass relative to the total amount of component (A) and colloidal silica.

[0179] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a viscous sheet. The rubber hardness on a Type A hardness tester was 22, the elongation at break was 540%, and the tensile strength at break was 0.80 MPa.

[0180] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0181] [Example 7]

[0182] The kinematic viscosity of 130 mm, represented by the above formula (A-1'), is... 2 / s, 266g of dimethyl polysiloxane containing vinyl groups at both ends of the molecular chain with a vinyl content of 0.035mol / 100g, and a kinematic viscosity of 430mm as expressed by the above formula (A-2'). 2 / s, 162g of methylhydrosiloxane containing 0.040mol / 100g of silane, and a kinematic viscosity of 35mm as expressed by the above formula (A-3'). 272g of a linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain, with a silyl group content of 0.066mol / 100g, was dissolved in a 1-liter glass beaker by stirring at 2000 rpm using a homogeneous mixer. The total number of silyl groups in the dimethylhydropolysiloxane containing vinyl groups of formula (A-1') and the methylhydropolysiloxane containing silyl groups of formula (A-2') and the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain of formula (A-3') is 1.21. Furthermore, the mass ratio of the methylhydropolysiloxane containing silyl groups of formula (A-2') to the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain of formula (A-3') is 69:31.

[0183] Next, 5g of sodium dodecyl sulfate (representing 1.0 part by weight relative to 100 parts by weight of silicone elastomer) and 130g of water were added. The mixture was stirred at 8000 rpm using a homogenizer, resulting in oil-in-water droplets, confirming thickening. Stirring was continued for another 15 minutes. While stirring at 2000 rpm, 353g of water was added for dilution. The mixture was then passed through a homogenizer under 100 MPa pressure to obtain a homogeneous white emulsion.

[0184] 790 g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device. After adjusting the temperature to 20–25 °C, 0.6 g of a platinum-vinyl-containing siloxane complex solution of isododecane (platinum content 0.5%) and 1.1 g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) (0.28 parts by mass relative to 100 parts by mass of silicone elastomer) were added under stirring. The mixture was stirred at this temperature for 12 hours to carry out the addition reaction of the vinyl-containing dimethyl polysiloxane of formula (A-1') with the methyl hydrosiloxane of formula (A-2') containing hydrosilyl groups and the linear dimethyl hydrosiloxane of formula (A-3') containing hydrosilyl groups at both ends of the molecular chain. Next, 8 g of phenoxyethanol as an antibacterial agent was added, and the mixture was stirred at this temperature for 10 minutes to obtain an aqueous silicone dispersion.

[0185] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 850 nm.

[0186] 53 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) was added to the obtained aqueous organosilicon dispersion (the amount of colloidal silica is 5.3 parts by mass relative to 100 parts by mass of organosilicon elastomer), and the mixture was stirred for 10 minutes to obtain the aqueous organosilicon dispersion. The amount of water in the aqueous organosilicon dispersion is 96.9 parts by mass relative to the total amount of component (A) and colloidal silica.

[0187] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a non-sticky sheet. The hardness of the sheet was 13 on a Type A hardness tester, the elongation at break was 25%, and the tensile strength at break was 0.11 MPa.

[0188] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0189] [Example 8]

[0190] The kinematic viscosity of 130 mm, represented by the above formula (A-1'), is... 2 / s, 275g of dimethyl polysiloxane containing vinyl groups at both ends of the molecular chain (0.035mol / 100g), and a kinematic viscosity of 430mm as expressed by the above formula (A-2'). 2 / s, 112g of methylhydrosiloxane containing silane with a silane content of 0.040mol / 100g, and a kinematic viscosity of 35mm as expressed by the above formula (A-3'). 2 113g of a linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain, with a silyl group content of 0.066mol / 100g, was dissolved in a 1-liter glass beaker by stirring at 2000 rpm using a homogeneous mixer. The total number of silyl groups in the dimethylhydropolysiloxane containing vinyl groups (A-1') and the linear dimethylhydropolysiloxane containing silyl groups (A-2') and the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain (A-3') is 1.24, relative to the 1 vinyl group in the dimethylhydropolysiloxane containing vinyl groups described above. Furthermore, the mass ratio of the methylhydropolysiloxane containing silyl groups (A-2') to the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain (A-3') is 50:50.

[0191] Next, 5g of sodium dodecyl sulfate (representing 1.0 part by weight relative to 100 parts by weight of silicone elastomer) and 130g of water were added. The mixture was stirred at 8000 rpm using a homogenizer, resulting in oil-in-water droplets, confirming thickening. Stirring was continued for another 15 minutes. While stirring at 2000 rpm, 353g of water was added for dilution. The mixture was then passed through a homogenizer under 100 MPa pressure to obtain a homogeneous white emulsion.

[0192] 790 g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device. After adjusting the temperature to 20–25 °C, 0.6 g of a platinum-vinyl-containing siloxane complex solution of isododecane (platinum content 0.5%) and 1.1 g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) (0.28 parts by mass relative to 100 parts by mass of silicone elastomer) were added under stirring. The mixture was stirred at this temperature for 12 hours to carry out the addition reaction of the vinyl-containing dimethyl polysiloxane of formula (A-1') with the methyl hydrosiloxane of formula (A-2') containing hydrosilyl groups and the linear dimethyl hydrosiloxane of formula (A-3') containing hydrosilyl groups at both ends of the molecular chain. Next, 8 g of phenoxyethanol as an antibacterial agent was added, and the mixture was stirred at this temperature for 10 minutes to obtain an aqueous silicone dispersion.

[0193] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 830 nm.

[0194] 177 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) was added to the obtained aqueous organosilicon dispersion (the amount of colloidal silica is 17.7 parts by mass relative to 100 parts by mass of organosilicon elastomer), and the mixture was stirred for 10 minutes to obtain the aqueous organosilicon dispersion. The amount of water in the aqueous organosilicon dispersion is 103.6 parts by mass relative to the total amount of component (A) and colloidal silica.

[0195] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a non-sticky sheet. The hardness of the sheet was 32 on a Type A hardness tester, the elongation at break was 270%, and the tensile strength at break was 0.81 MPa.

[0196] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0197] [Example 9]

[0198] The kinematic viscosity of 130 mm, represented by the above formula (A-1'), is... 2 / s, 325g of dimethyl polysiloxane containing vinyl groups at both ends of the molecular chain with a vinyl content of 0.035mol / 100g, and a kinematic viscosity of 430mm as expressed by the above formula (A-2'). 2 / s, 172g of methylhydrosiloxane containing silane with a silane content of 0.040mol / 100g, and a kinematic viscosity of 35mm as expressed by the above formula (A-3'). 2 103g of a linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain, with a silyl group content of 0.066mol / 100g, was dissolved in a 1-liter glass beaker by stirring at 2000 rpm using a homogeneous mixer. The total number of silyl groups in the dimethylhydropolysiloxane containing vinyl groups (A-1') and the linear dimethylhydropolysiloxane containing silyl groups (A-2') and the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain (A-3') is 1.20, relative to the 1 vinyl group in the dimethylhydropolysiloxane containing vinyl groups (A-1'). Furthermore, the mass ratio of the silyl groups in the methylhydropolysiloxane containing silyl groups (A-2'):(A-3') is 63:37.

[0199] Next, 6g of sodium dodecyl sulfate (representing 1.0 part by weight relative to 100 parts by weight of silicone elastomer), 10g of phenoxyethanol as an antibacterial agent, and 160g of water were added. The mixture was stirred at 8000 rpm using a homogenizer, resulting in oil-in-water droplets, confirming thickening. Stirring was continued for another 15 minutes. While stirring at 2000 rpm, 222g of water was added for dilution. The mixture was then passed through a homogenizer under a pressure of 100 MPa to obtain a homogeneous white emulsion.

[0200] 798g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device. After adjusting the temperature to 20-25°C, 0.6g of a platinum-vinyl-containing siloxane complex isododecane solution (platinum content 0.5%) and 0.6g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) were added under stirring (to a weight of 0.13 parts by weight relative to 100 parts by weight of silicone elastomer). The mixture was stirred at the stated temperature for 12 hours to carry out the addition reaction of the vinyl-containing dimethyl polysiloxane of (A-1') with the methyl hydrosiloxane of (A-2') containing hydrosilyl groups and the linear dimethyl hydrosiloxane containing hydrosilyl groups at both ends of the molecular chain of (A-3'), resulting in an aqueous silicone dispersion.

[0201] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 630 nm.

[0202] 212 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) was added to the obtained aqueous organosilicon dispersion (the amount of colloidal silica was 17.7 parts by mass relative to 100 parts by mass of organosilicon elastomer), and the mixture was stirred for 10 minutes to obtain an aqueous organosilicon dispersion. The amount of water in the aqueous organosilicon dispersion was 76.6 parts by mass relative to the total amount of component (A) and colloidal silica.

[0203] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a non-sticky sheet. The hardness of the sheet was 42 on a Type A hardness tester, the elongation at break was 200%, and the tensile strength at break was 1.1 MPa.

[0204] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0205] [Example 10]

[0206] The kinematic viscosity of 130 mm, represented by the above formula (A-1'), is... 2 / s, 275g of dimethyl polysiloxane containing vinyl groups at both ends of the molecular chain (0.035mol / 100g), and a kinematic viscosity of 430mm as expressed by the above formula (A-2'). 2 / s, 112g of methylhydrosiloxane containing silane with a silane content of 0.040mol / 100g, and a kinematic viscosity of 35mm as expressed by the above formula (A-3'). 2 113g of a linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain, with a silyl group content of 0.066mol / 100g, was dissolved in a 1-liter glass beaker by stirring at 2000 rpm using a homogeneous mixer. The total number of silyl groups in the dimethylhydropolysiloxane containing vinyl groups (A-1') and the linear dimethylhydropolysiloxane containing silyl groups (A-2') and the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain (A-3') is 1.24, relative to the 1 vinyl group in the dimethylhydropolysiloxane containing vinyl groups (A-1'). Furthermore, the mass ratio of the methylhydropolysiloxane containing silyl groups (A-2') to the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain (A-3') is 50:50.

[0207] Next, 10g of sodium dodecyl sulfate (representing 2.0 parts by weight relative to 100 parts by weight of the silicone elastomer) and 130g of water were added. The mixture was stirred at 8000 rpm using a homogenizer, resulting in oil-in-water droplets, confirming thickening. Stirring was continued for another 15 minutes. While stirring at 2000 rpm, 348g of water was added for dilution. The mixture was then passed through a homogenizer at 100 MPa to obtain a homogeneous white emulsion.

[0208] 790 g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device. After adjusting the temperature to 20–25 °C, 0.6 g of a platinum-vinyl-containing siloxane complex solution of isododecane (platinum content 0.5%) and 1.1 g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) (0.28 parts by mass relative to 100 parts by mass of silicone elastomer) were added under stirring. The mixture was stirred at this temperature for 12 hours to carry out the addition reaction of the vinyl-containing dimethyl polysiloxane of formula (A-1') with the methyl hydrosiloxane of formula (A-2') containing hydrosilyl groups and the linear dimethyl hydrosiloxane of formula (A-3') containing hydrosilyl groups at both ends of the molecular chain. Next, 8 g of phenoxyethanol as an antibacterial agent was added, and the mixture was stirred at this temperature for 10 minutes to obtain an aqueous silicone dispersion.

[0209] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 670 nm.

[0210] 177 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) was added to the obtained aqueous organosilicon dispersion (the amount of colloidal silica is 17.7 parts by mass relative to 100 parts by mass of organosilicon elastomer), and the mixture was stirred for 10 minutes to obtain the aqueous organosilicon dispersion. The amount of water in the aqueous organosilicon dispersion is 103.8 parts by mass relative to the total amount of component (A) and colloidal silica.

[0211] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a non-sticky sheet. The hardness of the sheet was 32 on a Type A hardness tester, the elongation at break was 120%, and the tensile strength at break was 0.67 MPa.

[0212] Using a glass pipette, drop approximately 0.02g of the obtained aqueous organosilicon dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. The solid material wrinkles and peels off, indicating the formation of a soft film.

[0213] [Comparative Example 1]

[0214] The kinematic viscosity of 130 mm, represented by the above formula (A-1'), is... 2 / s, 244g of dimethyl polysiloxane containing vinyl groups at both ends of the molecular chain with a vinyl content of 0.035mol / 100g, and a kinematic viscosity of 430mm as expressed by the above formula (A-2'). 2 256 g of a methylhydropolysiloxane containing silane (0.040 mol / 100 g) was placed in a 1-liter glass beaker and dissolved using a homogeneous mixer at 2000 rpm. The methylhydropolysiloxane containing silane has 1.20 silane units compared to the vinyl-containing dimethylpolysiloxane in (A-1') described above. This example contains a methylhydropolysiloxane containing silane that does not contain linear dimethylpolysiloxanes with silane units at both ends of the molecular chain.

[0215] Next, 5g of sodium dodecyl sulfate (representing 1.0 part by weight relative to 100 parts by weight of silicone elastomer) and 130g of water were added. The mixture was stirred at 8000 rpm using a homogenizer, resulting in oil-in-water droplets, confirming thickening. Stirring was continued for another 15 minutes. While stirring at 2000 rpm, 353g of water was added for dilution. The mixture was then passed through a homogenizer under 100 MPa pressure to obtain a homogeneous white emulsion.

[0216] 790 g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device. After adjusting the temperature to 20–25 °C, 0.6 g of a platinum-vinyl-containing siloxane complex isododecane solution (platinum content 0.5%) and 1.1 g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) were added under stirring (to a weight of 0.28 parts by weight relative to 100 parts by weight of the silicone elastomer). The mixture was stirred at this temperature for 12 hours to carry out the addition reaction of the vinyl-containing dimethyl polysiloxane of formula (A-1') with the methyl hydrosiloxane of formula (A-2') containing hydrosilyl groups. Next, 10 g of phenoxyethanol as an antibacterial agent was added, and the mixture was stirred at this temperature for 10 minutes to obtain an aqueous silicone dispersion. The amount of water in the aqueous silicone dispersion was 96.6 parts by weight relative to 100 parts by weight of component (A) above.

[0217] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 850 nm.

[0218] The aqueous organosilicon dispersion obtained by the above method, although a non-sticky dried product was obtained, was too brittle and could not be peeled off from the tray as a sheet.

[0219] [Comparative Example 2]

[0220] The kinematic viscosity of 130 mm, represented by the above formula (A-1'), is... 2 / s, 271g of dimethyl polysiloxane containing vinyl groups at both ends of the molecular chain with a vinyl content of 0.035mol / 100g, and a kinematic viscosity of 430mm as expressed by the above formula (A-2'). 2 / s, 137g of methylhydrosiloxane containing 0.040mol / 100g of silane, and a kinematic viscosity of 35mm as expressed by the above formula (A-3'). 292g of a linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain, with a silyl group content of 0.066mol / 100g, was dissolved in a 1-liter glass beaker by stirring at 2000 rpm using a homogeneous mixer. The total number of silyl groups in the dimethylhydropolysiloxane containing vinyl groups of formula (A-1') and the methylhydropolysiloxane containing silyl groups of formula (A-2') and the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain of formula (A-3') is 1.22. Furthermore, the mass ratio of the methylhydropolysiloxane containing silyl groups of formula (A-2') to the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain of formula (A-3') is 60:40.

[0221] Next, 45g of sodium dodecyl sulfate (resulting in 9.0 parts by weight relative to 100 parts by weight of silicone elastomer) and 60g of water were added. The mixture was stirred at 4000 rpm using a HOMODISPER, resulting in an oil-in-water droplet formation, which became ester-like. The stirring was continued for another 10 minutes. While stirring at 2000 rpm using a homogenizer, 383g of water was added, yielding a homogeneous white emulsion.

[0222] 790 g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device. After adjusting the temperature to 20–25 °C, 0.6 g of a platinum-vinyl-containing siloxane complex solution of isododecane (platinum content 0.5%) and 1.1 g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) (0.28 parts by mass relative to 100 parts by mass of silicone elastomer) were added under stirring. The mixture was stirred at this temperature for 12 hours to carry out the addition reaction of the vinyl-containing dimethyl polysiloxane of formula (A-1') with the methyl hydrosiloxane of formula (A-2') containing hydrosilyl groups and the linear dimethyl hydrosiloxane of formula (A-3') containing hydrosilyl groups at both ends of the molecular chain. Next, 10 g of phenoxyethanol as an antibacterial agent was added, and the mixture was stirred at this temperature for 10 minutes to obtain an aqueous silicone dispersion. The amount of water in the aqueous organosilicon dispersion is 88.6 parts by mass relative to 100 parts by mass of component (A) above.

[0223] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 470 nm.

[0224] The aqueous organosilicon dispersion obtained by the above method, although a non-sticky dried product was obtained, was too brittle and could not be peeled off from the tray as a sheet.

[0225] [Comparative Example 3]

[0226] In the aqueous organosilicon dispersion obtained in the same manner as Comparative Example 1, 53 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) was added (the amount of colloidal silica was 5.3 parts by mass relative to 100 parts by mass of organosilicon elastomer), and the mixture was stirred for 10 minutes to obtain an aqueous organosilicon dispersion. The amount of water in the aqueous organosilicon dispersion was 91.7 parts by mass relative to the total amount of component (A) and colloidal silica.

[0227] The aqueous organosilicon dispersion obtained by the above method, although a non-sticky dried product was obtained, was too brittle and could not be peeled off from the tray as a sheet.

[0228] [Comparative Example 4]

[0229] Except that 5g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) was used instead of 5g of sodium dodecyl sulfate used in Example 1, an aqueous organosilicon dispersion was obtained using the same method as in Example 1. The amount of water in the aqueous organosilicon dispersion was 96.6 parts by mass relative to 100 parts by mass of component (A) above.

[0230] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 720 nm.

[0231] The aqueous organosilicon dispersion obtained by the above method, although a non-sticky dried product was obtained, was too brittle and could not be peeled off from the tray as a sheet.

[0232] [Comparative Example 5]

[0233] The kinematic viscosity of 130 mm, represented by the above formula (A-1'), is... 2 / s, 271g of dimethyl polysiloxane containing vinyl groups at both ends of the molecular chain with a vinyl content of 0.035mol / 100g, and a kinematic viscosity of 430mm as expressed by the above formula (A-2'). 2 / s, 137g of methylhydrosiloxane containing silane with a silane content of 0.040mol / 100g, and a kinematic viscosity of 35mm as expressed by the above formula (A-3'). 292g of a linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain, with a silyl group content of 0.066mol / 100g, was placed in a 1-liter glass beaker and dissolved by stirring at 2000 rpm using a homogeneous mixer. The total number of silyl groups in the dimethylhydropolysiloxane containing vinyl groups of formula (A-1') is 1.22, relative to 1 vinyl group. Furthermore, the mass ratio of the methylhydropolysiloxane containing silyl groups of formula (2) to the linear dimethylhydropolysiloxane containing silyl groups at both ends of its molecular chain of formula (A-3') is 60:40.

[0234] Next, 5g of sodium dodecyl sulfate (representing 1.0 part by mass relative to 100 parts by mass of silicone elastomer), 25g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles), and 40g of water were added. The mixture was stirred at 4000 rpm using a HOMODISPER, resulting in an oil-in-water droplet formation, becoming a grease-like consistency. Stirring was continued for another 10 minutes. While stirring at 2000 rpm using a homogeneous mixer, 418g of water was added, yielding a homogeneous white emulsion.

[0235] 790 g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device. After adjusting the temperature to 20–25 °C, 0.6 g of a platinum-vinyl-containing siloxane complex solution of isododecane (platinum content 0.5%) and 1.1 g of polyoxyethylene dodecyl ether (ethylene oxide addition molar number = 9 moles) (0.28 parts by mass relative to 100 parts by mass of silicone elastomer) were added under stirring. The mixture was stirred at this temperature for 12 hours to carry out the addition reaction of the vinyl-containing dimethyl polysiloxane of formula (A-1') with the methyl hydrosiloxane of formula (A-2') containing hydrosilyl groups and the linear dimethyl hydrosiloxane of formula (A-3') containing hydrosilyl groups at both ends of the molecular chain. Next, 10 g of phenoxyethanol as an antibacterial agent was added, and the mixture was stirred at this temperature for 10 minutes to obtain an aqueous silicone dispersion. The amount of water in the aqueous organosilicon dispersion is 91.6 parts by mass relative to 100 parts by mass of component (A) above.

[0236] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 660 nm.

[0237] The aqueous organosilicon dispersion obtained by the above method, although a non-sticky dried product was obtained, was too brittle and could not be peeled off from the tray as a sheet.

[0238] [Comparative Example 6]

[0239] 360 g of a 40% colloidal silica aqueous dispersion (trade name: COSMO S-40, manufactured by Nichiki Catalyst Chemical Co., Ltd.) was added to the aqueous silicone dispersion obtained in the same manner as in Example 1 (the amount of colloidal silica is 36.0 parts by mass relative to 100 parts by mass of silicone elastomer), and the mixture was stirred for 10 minutes to obtain the aqueous silicone dispersion. The amount of water in the aqueous silicone dispersion was 109.8 parts by mass relative to the total of 100 parts by mass of the above-mentioned component (A) and colloidal silica.

[0240] The aqueous organosilicon dispersion obtained by the above method, although a non-sticky dried product was obtained, was too brittle and could not be peeled off from the tray as a sheet.

[0241] [Comparative Example 7]

[0242] 500g of octamethylcyclotetrasiloxane, 30g of dodecylbenzenesulfonic acid (used as an emulsifier and polymerization catalyst), and 170g of water were placed in a 1-liter glass beaker and stirred at 8000 rpm using a homogenizer. The mixture formed oil-in-water droplets, confirming thickening, and stirring was continued for 15 minutes. While stirring at 2000 rpm, 300g of water was added to dilute the mixture. The emulsion was then passed through a homogenizer under a pressure of 30 MPa to obtain a homogeneous white emulsion.

[0243] 800g of the obtained emulsion was transferred to a 2-liter glass flask equipped with an anchor-type stirring device and reacted at 70°C for 6 hours, followed by aging at 15°C for 12 hours. Then, 44g of a 10% (w / w) sodium carbonate aqueous solution was added to neutralize the emulsion to pH 6.2. The polysiloxane in the resulting emulsion was dimethylpolysiloxane containing hydroxyl groups at both ends of the molecular chain. Isopropanol was added to the emulsion to disrupt it, and the complex viscosity of the polysiloxane was measured to be 2.3 × 10⁻⁶. 6 mPa·s.

[0244] To 787 g of a dimethyl polysiloxane emulsion containing hydroxyl groups at both ends of the molecular chain, 8 g of phenyltriethoxysilane was added under stirring. After stirring for 1 hour, 4.8 g of a dioctyltin ditert-tert-carbonate emulsion (42% concentration) as a condensation catalyst and 8 g of phenoxyethanol as an antibacterial agent were further added. After stirring for 10 minutes, an aqueous organosilicon dispersion was obtained. The amount of water in the aqueous organosilicon dispersion was 103.2 parts by mass relative to the total 100 parts by mass of the polysiloxane and phenyltriethoxysilane.

[0245] The volume average particle size of the silicone elastomer contained in the aqueous silicone dispersion was measured using a laser diffraction / scattering particle size distribution measuring device "LA-960" (manufactured by Horiba Corporation), and the result was 220 nm.

[0246] The aqueous organosilicon dispersion obtained by drying using the above method resulted in a non-sticky sheet. The rubber hardness on a Type A hardness tester was 12, the elongation at break was 860%, and the tensile strength at break was 0.60 MPa.

[0247] Using a glass pipette, drop approximately 0.02g of the obtained aqueous silicone dispersion onto a fingernail and spread it out with your finger to a size approximately 2cm in diameter. After air drying for 3 minutes, rub vigorously with your finger. No solid material came off, and no cured film formed despite the short drying time.

Claims

1. An aqueous organosilicon dispersion containing the following (A) organosilicon elastomer, which is an aqueous organosilicon dispersion that forms an elastomer film by drying at room temperature, comprising: (A) An organosilicon elastomer, which is an addition reaction product of an alkenyl-containing organopolysiloxane (A-1) having two or more alkenyl groups in one molecule, represented by the average composition formula (1) below, an organohydrosiloxane (A-2) having three or more hydrosilyl groups in one molecule, represented by the average composition formula (6) below, and a linear diorganohydrosiloxane (A-3) having hydrosilyl groups only at both ends of the molecular chain, represented by the average composition formula (11) below, wherein, The mass ratio of component (A-2) to component (A-3) is 5:95 to 90:

10. R 1 a R 2 b SiO (4-a-b) / 2 (1) In the formula, R 1 Independently, R is a monovalent hydrocarbon group with 1 to 30 carbon atoms, excluding alkenyl groups, and either substituted or unsubstituted. 2 Independently, it is an alkenyl group with 2 to 6 carbon atoms, where a and b are positive numbers satisfying 0 < a < 3, 0 < b ≤ 3, and 0.1 ≤ a + b ≤ 3. R 3 w H x SiO (4-w-x) / 2 (6) In the formula, R 3 Independently, it refers to a monovalent hydrocarbon group with 1 to 30 carbon atoms, excluding alkenyl groups, and either substituted or unsubstituted, where w and x are positive numbers satisfying 0 < w < 3, 0 < x ≤ 3, and 0.1 ≤ w + x ≤ 3. In the formula, R 4 Independently, it is a monovalent hydrocarbon group with 1 to 30 carbon atoms, excluding alkenyl groups, and substituted or unsubstituted, with s1 being a positive number from 5 to 1000. (B) Anionic surfactant: 0.1 to 5 parts by weight relative to 100 parts by weight of component (A), (C) Nonionic surfactant: 0-2 parts by weight relative to 100 parts by weight of component (A), (D) Colloidal silica: 0–35 parts by mass relative to 100 parts by mass of component (A), and (E) Water: 15-200 parts by mass relative to the total of components (A) and (D) by mass. The coating is a coating that satisfies the following: In the determination of an elastomer sheet with a thickness of 1 mm as the 25°C dried product of the aqueous organosilicon dispersion, Based on the test methods specified in the Japan Rubber Industry Association's standard specifications, Asker C rubber has a hardness of 5 or higher and 60 or lower. According to the test method specified in JIS K 6251, the elongation at break is 20% or more, and the tensile strength at break is 0.05 MPa or more and 5.0 MPa or less.

2. The aqueous organosilicon dispersion according to claim 1, wherein, (A-3) is a linear diorganohydropolysiloxane with two hydrogen silyl groups at both ends of the molecular chain per molecule.

3. An elastomer film obtained by drying the aqueous organosilicon dispersion according to any one of claims 1 to 2 at room temperature.

4. A cosmetic ingredient comprising an aqueous organosilicon dispersion according to any one of claims 1 to 2.

5. The cosmetic material according to claim 4, wherein it is selected from makeup cosmetic materials, skin care cosmetic materials, and eyelash cosmetic materials.

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