JP5907248B2 - Zinc carbonate salt particles, zinc oxide particles, production method thereof, heat dissipating filler and cosmetic - Google Patents

Description

The present invention relates to zinc carbonate salt particles, zinc oxide particles, a production method thereof, a heat dissipating filler, and a cosmetic.

In cosmetic applications, zinc oxide particles having ultrafine particles having an average particle diameter of 100 nm or less are used as sunscreen ultraviolet screening agents. However, ultrafine zinc oxide for shielding ultraviolet rays is hardly used for foundations because it deteriorates slipperiness. Therefore, it is common to blend plate-like particles such as talc, mica and barium sulfate in order to impart slipperiness. However, since these plate-like particles have no ultraviolet shielding effect, in order to impart ultraviolet shielding properties, a very small amount of fine zinc oxide, fine titanium oxide, or organic ultraviolet absorber that does not inhibit slipperiness is used in combination. I must.

On the other hand, the star-shaped zinc oxide is known from Patent Document 1. Further, a tetrapotted zinc oxide is known from Patent Document 2. However, these particles are not zinc oxide particles that seek to improve slipperiness. In addition, zinc oxide particles having various shapes are known, but tetrahedral zinc oxide particles are not known.

Furthermore, use of zinc oxide particles as a heat-dissipating filler is also being studied (Patent Documents 3 and 4). Such zinc oxide particles had a particle diameter of 0.1 μm or more and preferably had a specific shape. However, it is not known to use tetrahedral zinc oxide particles as a heat-dissipating filler.

JP 2010-195672 A Japanese Patent No. 2678101 International Publication No. 2011/043207 International Publication 2010/050139

In view of the above problems, the present invention provides novel zinc oxide particles having a tetrahedral shape and / or a tetrahedral pair shape suitable for uses such as cosmetic raw materials and heat-dissipating fillers, and zinc carbonate salt particles serving as the raw materials thereof. It is intended to provide.

The present invention is tetrahedral and / or tetrahedral paired zinc carbonate particles having a median diameter of 0.1 μm or more.

The present invention is tetrahedral and / or tetrahedral paired zinc oxide particles having a median diameter of 0.1 μm or more.
The zinc oxide particles of the present invention preferably have an MIU (average friction coefficient) of 1.0 or less.
The zinc oxide particles of the present invention preferably have a D90 / D10 in the particle size distribution of 4.0 or less.

The present invention has the step (1) of neutralizing a zinc salt aqueous solution or an emulsion obtained by emulsifying a zinc salt aqueous solution with an organic solvent with a bicarbonate metal salt, and / or the tetrahedral and / or tetrahedral surfaces described above. It is also a method for producing body-facing zinc carbonate salt particles.
The present invention comprises a step (1) of neutralizing an aqueous zinc salt solution or an emulsion obtained by emulsifying an aqueous zinc salt solution with an organic solvent with a bicarbonate metal salt, and / or a tetrahedral shape obtained by the step (1) and / or It is also a method for producing the tetrahedral and / or tetrahedral paired zinc oxide particles described above including the step (2) of thermally decomposing tetrahedral paired zinc carbonate particles.

The present invention is also a heat dissipating filler characterized by containing the tetrahedral and / or tetrahedral paired zinc oxide particles described above.
The present invention is also a cosmetic characterized by containing the tetrahedral and / or tetrahedral paired zinc oxide particles described above.

The zinc oxide particles of the present invention have a median diameter of 0.1 μm and a relatively large particle size, and since they have a tetrahedral shape and / or a tetrahedral pair shape, they have good slipperiness, An excellent feel can be obtained when used in cosmetic applications. Moreover, since it is excellent also in visible light transparency, it can be used as a highly transparent ultraviolet protective agent for cosmetics.

Further, in the case of tetrahedral and / or tetrahedral pair-like zinc oxide particles as in the present invention, for example, when a molded body is prepared by kneading with a resin, the particles are in a small occupied volume inside the molded body. Will be linked. By connecting the particles with such a small occupied volume, heat conduction percolation is formed even with a smaller amount than zinc oxide particles having a spherical shape, rod shape, needle shape, plate shape, etc., and more efficiently. This is preferable in that heat conduction can be increased.

Furthermore, the zinc carbonate salt particles of the present invention can be suitably used as a raw material for producing zinc oxide particles having the properties described above.

2 is a scanning electron micrograph of tetrahedral paired zinc carbonate salt particles of the present invention obtained in Example 1. FIG. 2 is a scanning electron micrograph of the tetrahedral zinc carbonate salt particles of the present invention obtained by Example 1. FIG. 2 is an X-ray diffraction spectrum of tetrahedral and tetrahedral paired zinc carbonate particles of the present invention obtained in Example 1. FIG. 2 is a scanning electron micrograph of tetrahedral and tetrahedral paired zinc oxide particles of the present invention obtained in Example 2. FIG. 2 is an X-ray diffraction spectrum of tetrahedral and tetrahedral paired zinc oxide particles of the present invention obtained in Example 2. FIG. 2 is a scanning electron micrograph of tetrahedral and tetrahedral paired zinc carbonate particles of the present invention obtained in Example 3. FIG. 2 is an X-ray diffraction spectrum of tetrahedral and tetrahedral paired zinc carbonate particles of the present invention obtained in Example 3. FIG. 4 is a scanning electron micrograph of tetrahedral and tetrahedral paired zinc oxide particles of the present invention obtained by Example 4. FIG. 4 is an X-ray diffraction spectrum of tetrahedral and tetrahedral paired zinc oxide particles of the present invention obtained in Example 4. FIG. 2 is a scanning electron micrograph of spherical zinc carbonate particles obtained in Comparative Example 1. 3 is an X-ray diffraction spectrum of spherical zinc carbonate particles obtained in Comparative Example 1. FIG. 3 is a scanning electron micrograph of spherical zinc oxide particles obtained in Comparative Example 2. FIG. 3 is an X-ray diffraction spectrum of spherical zinc oxide particles obtained in Comparative Example 2. FIG. 4 is a scanning electron micrograph of zinc oxide particles obtained in Comparative Example 3. It is a model figure of the tetrahedral shape and tetrahedral pair-like particle | grains which were obtained by this invention.

The zinc carbonate salt of the present invention has the following general formula M ₂ Zn ₃ (CO ₃ ) ₄
It is a compound represented by these. In the formula, M is preferably sodium, potassium, lithium or the like.

The zinc carbonate salt may contain crystal water in the crystalline state. For example, a structure such as Na ₂ Zn ₃ (CO ₃ ) ₄ (H ₂ O) ₃ may be employed.

The zinc carbonate salt particles of the present invention are characterized by having a tetrahedral shape and / or a tetrahedral pair shape. By firing such zinc carbonate salt particles, zinc oxide particles having a tetrahedral shape and / or a tetrahedral pair shape can be obtained. For this reason, it can be used as a raw material for obtaining zinc oxide having the effects described above. It can also be used in normal applications of zinc carbonate such as pigments, ceramics, fireproofing agents, cosmetics, pharmaceuticals (ointment), rubber compounding agents, mineral feeds, galvanizing and the like.
The tetrahedral and / or tetrahedral pair-like zinc oxide particles as described above can provide a good powder feel in addition to the ultraviolet shielding effect of zinc oxide.
In addition, the figure which shows a tetrahedron shape and a tetrahedron pair shape is shown in FIG. The zinc carbonate salt particles and zinc oxide particles of the present invention have such a specific shape.

The tetrahedral shape and / or the tetrahedral pair shape referred to in the present specification indicate that when the particle shape is observed by an electron micrograph, 60% or more of the particles have a tetrahedral shape and / or a tetrahedral pair shape. It refers to what you have. The tetrahedron shape is not particularly limited, but is more preferably a shape close to a regular tetrahedron shape.

The tetrahedral pair shape referred to in this specification is a composite shape in which two tetrahedral shapes are connected. The tetrahedral shape and / or tetrahedral pair shape of the present invention may be an aggregate of tetrahedral particles, an aggregate of tetrahedral particles, or both. Particles in a mixed state may be used.

The zinc carbonate salt particles of the present invention have a median diameter of 0.1 μm or more. By using such zinc carbonate salt particles having a relatively large particle size, zinc oxide particles having a large particle size can be obtained. The median diameter is more preferably 0.5 μm or more, and further preferably 1.0 μm or more. The upper limit of the median diameter is not particularly limited, but is preferably 100 μm or less, more preferably 50 μm or less, and further preferably 20 μm or less.

In this specification, the median diameter refers to a diameter in which the large side and the small side are equivalent when the powder is divided into two from a certain particle diameter. In this specification, laser diffraction / scattering type particle size distribution measurement is performed. It is a value measured by an apparatus LA-750 (manufactured by Horiba Seisakusho).

The zinc carbonate salt particles of the present invention preferably have a D90 / D10 of 4.0 or less. By using such zinc carbonate salt particles, zinc oxide particles having D90 / D10 of 4.0 or less can be obtained by firing. D10 and D90 are values obtained by measuring the particle size distribution. D10 means 10% cumulative particle diameter on a volume basis, and D90 means 90% cumulative particle diameter on a volume basis. These values are values measured by the same method as the median diameter. The D90 / D10 is more preferably 3.5 or less.

The method for producing the zinc carbonate salt particles of the present invention is not limited. For example, a zinc salt aqueous solution or a step of neutralizing an emulsion obtained by emulsifying a zinc salt aqueous solution with an organic solvent with a metal bicarbonate ( 1). Such a method for producing zinc carbonate salt particles is also one aspect of the present invention. By such a method, a tetrahedral shape and / or a tetrahedral pair shape can be obtained according to the characteristics of the crystal growth direction of the zinc carbonate salt.

In such a production method, an aqueous zinc salt solution or an emulsion obtained by emulsifying an aqueous zinc salt solution with an organic solvent is used as a raw material. The zinc salt used as a raw material is not particularly limited, and examples thereof include zinc salts of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, oxalic acid and fatty acids, and other organic acid zinc salts. One or more of these zinc salts can be used.

As the zinc salt aqueous solution, for example, a solution obtained by dissolving the zinc salt in water at a concentration of 0.3 to 4.0 mol / l can be used. The zinc salt aqueous solution may be added with other components such as a water-miscible organic solvent and a dispersant as long as the object of the present invention is not impaired.

An emulsion obtained by emulsifying an aqueous zinc salt solution with an organic solvent refers to an emulsion obtained by emulsifying the aqueous zinc salt solution with an organic solvent. When the reaction is performed in the above emulsion, it is preferable in that the size of the zinc carbonate particles obtained after the reaction can be controlled by controlling the size of the emulsion droplets. Moreover, it is preferable at the point that the particle size distribution of the zinc carbonate salt particle | grains obtained after reaction can be made sharp. The organic solvent is not particularly limited as long as it is not miscible with water. Hydrocarbon organic solvents such as toluene, xylene, benzene, cyclohexane and hexane, ester organic solvents such as ethyl acetate, and ketone organic solvents. And ether-based organic solvents such as diethyl ether.
The organic solvent is preferably used in a proportion of 20 to 80% by weight based on the total amount of the emulsion.

In order to obtain the emulsion, it is preferable to use an emulsifier. The emulsifier that can be used is not particularly limited. For example, polycarboxylic acid or a salt thereof, alkylsulfonic acid or a salt thereof, alkylbenzenesulfonic acid or a salt thereof, naphthalenesulfonic acid or a salt thereof, polyether alkylsulfonic acid or a salt thereof. Salt, alkyl betaine, polyether or derivative thereof, polyether alkyl ether, polyoxyalkylene alkenyl phenyl ether, sorbitan fatty acid ester, polyether sorbitan fatty acid ester, polyether fatty acid ester, glycerin fatty acid ester, polyether hydrogenated castor oil, polyether Examples include alkylamines, polyether-modified silicones, polyglycerin-modified silicones, polyhydric alcohols, and alkyl-modified polyhydric alcohols. Any of anionic, cationic, and nonionic materials can be used, but they are not easily affected by water hardness and electrolytes, and they are easy to handle and can be used in combination with various other surfactants. Are preferred. Moreover, when the HLB value of the emulsifier is in the range of 0 to 9 (so-called lipophilic dispersant), the stability of the emulsion droplets is increased and the droplets are less likely to break during the reaction. Two or more of the above emulsifiers may be used in combination. In addition, in this specification, the HLB value is expressed by the formula HLB of Griffin = (sum of formula weight of hydrophilic group part of emulsifier / molecular weight of emulsifier) × (100/5)
It is a value obtained by the calculation method. Moreover, it is preferable that the addition amount of an emulsifier is 0.1 to 20 weight% with respect to the said total amount of emulsion.

In the said emulsion, it is preferable that the amount of zinc salt aqueous solution is contained in the ratio of 20 to 80 weight% with respect to the total amount of emulsion. Furthermore, it is preferable that the said emulsifier is contained in the ratio of 0.1 to 20 weight% with respect to the total amount of emulsion.

The emulsion may be O / W type or W / O type, but is preferably W / O type. When the W / O type emulsion is mixed with the aqueous bicarbonate solution in step (1), it can be easily made into a W / O / W emulsion. When the reaction is allowed to proceed in the W / O / W type emulsion, the heat treatment required for proceeding the reaction of the O / W type or W / O type emulsion is not required. It is preferable in that it can be used.

In the step (1) of the present invention, the zinc salt is reacted with a bicarbonate metal salt such as sodium bicarbonate, potassium bicarbonate, lithium bicarbonate and the like. In order to obtain the zinc carbonate salt particles having the specific shape of the present invention, it is important to react the zinc salt with a metal bicarbonate salt. In other words, when zinc salt is reacted with carbonates such as sodium carbonate, potassium carbonate, and ammonium carbonate, zinc carbonate salt particles having a specific shape as in the present invention cannot be obtained, but are reacted with metal bicarbonate. Thus, zinc carbonate salt particles having a specific shape can be obtained. The reason why such a specific effect is obtained when using a metal bicarbonate as a neutralizing agent is not clear, but the crystallinity of the zinc carbonate particles obtained after the reaction is improved, and the crystals of the zinc carbonate salt are improved. It is presumed that the shape is controlled in the growth direction.

The method of adding the bicarbonate metal salt is not particularly limited. For example, a solid metal bicarbonate solution is added to an aqueous zinc salt solution or an emulsion obtained by emulsifying an aqueous zinc salt solution with an organic solvent, and an aqueous bicarbonate solution is added. Examples include a method of adding an aqueous zinc salt solution or an emulsion obtained by emulsifying an aqueous zinc salt solution with an organic solvent, and a method of adding an aqueous zinc salt solution or an emulsion obtained by emulsifying an aqueous zinc salt solution to an aqueous metal bicarbonate solution. . Among these, a method of adding an aqueous zinc salt solution or an emulsion obtained by emulsifying an aqueous zinc salt solution with an organic solvent to the aqueous metal bicarbonate solution is particularly preferable.

An aqueous emulsifier may be added to the aqueous bicarbonate solution. The emulsifier added in this case is not particularly limited, and those described above can be used. The HLB value of the emulsifier added to the aqueous bicarbonate solution is preferably 10 to 20 (so-called hydrophilic dispersant). Addition of such an emulsifier is particularly preferred in that a W / O / W type emulsion can be easily obtained when mixed with the above emulsion.

The emulsifier added to the aqueous bicarbonate metal salt solution is preferably 0.1 to 20% by weight based on the total amount of the aqueous bicarbonate metal salt solution. By setting it as the said ratio, it is preferable at the point which can obtain a W / O / W type | mold emulsion easily.

The metal bicarbonate salt is not particularly limited, and examples thereof include sodium hydrogen carbonate, potassium hydrogen carbonate, and lithium hydrogen carbonate. In the step (1), the bicarbonate metal salt is preferably added at a ratio of 2 to 10 moles of the bicarbonate metal salt with respect to 1 mole of the zinc salt. By adding in such a range, the target zinc carbonate salt particles can be obtained with an equivalent amount of raw materials. Moreover, when using the said bicarbonate metal salt, 2 or more types may be used together.

Although the reaction temperature and time in the said process (1) are not specifically limited, For example, the target zinc carbonate salt particle | grains can be obtained by making it react for 0.5 to 12 hours at 10-60 degreeC. .

The zinc carbonate salt particles obtained by the reaction can be subjected to usual treatments such as water washing, alcohol washing, and drying. Further, the zinc carbonate salt particles obtained in this way may be subjected to pulverization, classification with a sieve, or the like, if necessary. Examples of the classification method using a sieve include wet classification and dry classification.

The zinc oxide particles of the present invention are also tetrahedral and / or tetrahedral paired zinc oxide particles having a median diameter of 0.1 μm or more. Such a specific shape exhibits specific properties such as slipperiness and thermal conductivity.

The zinc oxide particles of the present invention are preferably obtained by firing the zinc carbonate salt particles described above. That is, when zinc carbonate salt is baked, zinc oxide can be obtained. At that time, the shape of the zinc carbonate salt can be maintained to obtain zinc oxide. For this reason, zinc oxide particles having a tetrahedral shape and / or a tetrahedral pair shape can be obtained by firing the tetrahedral and / or tetrahedral pair-shaped zinc carbonate particles described above. It is.

It does not specifically limit as a process of baking zinc carbonate salt particle | grains, For example, it can carry out at 230-900 degreeC by methods, such as stationary baking.

The zinc oxide particles obtained by firing can be subjected to ordinary treatments such as washing with water and drying. Further, the zinc oxide particles obtained in this way may be subjected to pulverization, classification with a sieve, or the like, if necessary. Examples of the classification method using a sieve include wet classification and dry classification.

The zinc oxide particles of the present invention have a median diameter of 0.1 μm or more. By making it 0.1 μm or more, good slipperiness can be obtained when blended in cosmetics, which is preferable in that it can be suitably used for a foundation. Moreover, when using as a heat dissipation filler, in order to obtain high heat dissipation, it is preferable that a particle diameter is large. The median diameter is more preferably 0.5 μm or more. Further, the upper limit of the median diameter is not particularly limited, but for example, it is preferably 100 μm or less.

The zinc oxide particles of the present invention preferably have an MIU (average friction coefficient) of 1.0 or less.
The MIU (average coefficient of friction) in the present specification is measured by the method described in detail in the examples. Zinc oxide particles having an MIU (average coefficient of friction) exceeding 1.0 are inferior in usability in terms of poor slipperiness when blended in cosmetics. The MIU (average friction coefficient) is more preferably 0.8 or less.

The zinc oxide particles of the present invention preferably have an MMD (average deviation of friction coefficient) of 0.02 or less. The MMD (average deviation of the coefficient of friction) in the present specification is measured by the method detailed in the present specification. Zinc oxide particles having an MMD (average deviation of friction coefficient) exceeding 0.02 are inferior in usability in that they are rough when blended in cosmetics. The MMD (average deviation of friction coefficient) is more preferably 0.015 or less.

The zinc oxide particles of the present invention preferably have a D90 / D10 in the particle size distribution of 4.0 or less.
That is, it is preferable that the ratio between D90 and D10 is small (that is, the particle diameter is extremely large with respect to the average particle diameter or the number of small particles is small). By making the particle size distribution sharp by reducing the number of particles that are extremely large or small relative to the average particle size in this way, particles of any size can be arbitrarily mixed and more closely packed. It is preferable at the point which can produce the heat dissipation filler which can be filled. The D90 / D10 is more preferably 3.5 or less.

In such tetrahedral and / or tetrahedral pair-like zinc oxide particles, for example, when a molded body is prepared by kneading with a resin, the particles are connected with a small occupied volume inside the molded body. It will be. By connecting the particles with such a small occupied volume, heat conduction percolation is formed even with a smaller amount than zinc oxide particles having a spherical shape, rod shape, needle shape, plate shape, etc., and more efficiently. This is preferable in that heat conduction can be increased.

The tetrahedral and / or tetrahedral pair-like zinc oxide particles of the present invention may be subjected to a surface treatment after firing. The surface treatment is not particularly limited, and examples include a surface treatment with a surface treatment agent selected from an organosilicon compound, an organoaluminum compound, an organotitanium compound, a higher fatty acid, a higher fatty acid ester, a metal soap, a polyhydric alcohol, or an alkanolamine. be able to. Such a surface treating agent can set a processing amount suitably according to the particle diameter of the said tetrahedral shape and / or tetrahedral pair-like zinc oxide particle.

The tetrahedral and / or tetrahedral pair-like zinc oxide particles of the present invention can be used as a cosmetic ingredient. Such cosmetics are also part of the present invention. The tetrahedral and / or tetrahedral pair-like zinc oxide particles have a smooth feel and have excellent performance in ultraviolet shielding properties, and therefore can be suitably used in cosmetics. Examples of the cosmetic of the present invention include foundations, makeup bases, eye shadows, blushers, mascara, lipsticks, sunscreen agents, and the like. The cosmetics of the present invention can be in any form of oily cosmetics, aqueous cosmetics, O / W type cosmetics, and W / O type cosmetics. Among these, it can be particularly preferably used in makeup cosmetics such as foundations, makeup bases, and eye shadows.

The cosmetic of the present invention may be used in combination with any aqueous component or oily component that can be used in the cosmetic field, in addition to the components constituting the mixture. The aqueous component and the oil component are not particularly limited, and examples thereof include oils, surfactants, moisturizers, higher alcohols, sequestering agents, natural and synthetic polymers, water-soluble and oil-soluble polymers, UV shielding agents, Various extracts, inorganic and organic pigments, various powders such as inorganic and organic clay minerals, inorganic and organic pigments treated with metal soap or silicone, organic dyes and other colorants, preservatives, antioxidants, dyes, You may contain components, such as a thickener, a pH adjuster, a fragrance | flavor, a cooling agent, an antiperspirant, a disinfectant, and a skin activator. Specifically, it is possible to produce any desired cosmetic by a conventional method by arbitrarily blending one or more of the blending ingredients listed below. The compounding amounts of these compounding components are not particularly limited as long as the effects of the present invention are not impaired.

The oil content is not particularly limited. For example, avocado oil, camellia oil, turtle oil, macadamia nut oil, corn oil, mink oil, olive oil, rapeseed oil, egg yolk oil, sesame oil, persic oil, wheat germ oil, sasanqua oil, castor Oil, flaxseed oil, safflower oil, cottonseed oil, eno oil, soybean oil, peanut oil, tea seed oil, kaya oil, rice bran oil, Japanese kiri oil, jojoba oil, germ oil, triglycerin, glyceryl trioctanoate, triisopalmitin Acid glycerin, cocoa butter, coconut oil, horse oil, palm oil, beef tallow, sheep fat, hardened beef tallow, palm kernel oil, pork tallow, beef bone fat, hardened oil, beef leg fat, owl, hardened castor oil, beeswax, candelilla wax Cotton wax, carnauba wax, bayberry wax, ibotarou, whale wax, montan wax, nukarou, lanolin, kapok wax, lanolin acetate, Lanolin, sugarcane wax, lanolin fatty acid isopropyl, hexyl laurate, reduced lanolin, hard lanolin, shellac wax, POE lanolin alcohol ether, POE lanolin alcohol acetate, POE cholesterol ether, lanolin fatty acid polyethylene glycol, POE hydrogenated lanolin alcohol ether, liquid paraffin And ozokerite, pristane, paraffin, ceresin, squalene, petrolatum, and microcrystalline wax.

The lipophilic nonionic surfactant is not particularly limited. For example, sorbitan monooleate, sorbitan monoisostearate, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan sesquioleate, sorbitan trioleate. Sorbitan fatty acid esters such as diglycerol sorbitan penta-2-ethylhexylate, diglycerol sorbitan tetra-2-ethylhexylate, mono-cotton oil fatty acid glycerin, glyceryl monoerucate, glyceryl sesquioleate, glyceryl monostearate, α, α '-Oleic acid pyroglutamate glycerol, monostearate glycerol malic acid and other (poly) glycerol fatty acid esters, propylene glycol monostearate propylene glycol and the like Glycol fatty acid esters, hardened castor oil derivatives, and glycerol alkyl ether.

The hydrophilic nonionic surfactant is not particularly limited. For example, POE sorbitan fatty acid esters such as POE sorbitan monooleate, POE sorbitan monostearate, POE sorbitan tetraoleate, POE sorbite monolaurate, and POE sorbite mono POE sorbite fatty acid esters such as oleate, POE sorbite pentaoleate, POE sorbite monostearate, POE glycerin fatty acid esters such as POE glycerin monostearate, POE glycerin monoisostearate, POE glycerin triisostearate, POE POE fatty acid esters such as monooleate, POE distearate, POE monodiolate, ethylene glycol distearate, POE lauryl ether, POE POE alkyl ethers such as yl ether, POE stearyl ether, POE behenyl ether, POE 2 -octyldodecyl ether, POE cholestanol ether, POE alkyl phenyl ethers such as POE octyl phenyl ether, POE nonyl phenyl ether, POE dinonyl phenyl ether Pluaronic types such as Pluronic, POE / POP cetyl ether, POE / POP2-decyltetradecyl ether, POE / POP monobutyl ether, POE / POP hydrogenated lanolin, POE / POP alkyl ethers such as POE / POP glycerin ether, Tetronic PEO / TetraPOP ethylenediamine condensates, POE castor oil, POE hydrogenated castor oil, POE hydrogenated castor oil monoisos POE castor oil triisostearate, POE cured castor oil monopyroglutamic acid monoisostearic acid diester, POE castor oil cured castor oil derivatives such as POE cured castor oil maleic acid, POE beeswax and lanolin derivatives such as POE sorbite beeswax, Alkanolamides such as coconut oil fatty acid diethanolamide, lauric acid monoethanolamide, fatty acid isopropanolamide, POE propylene glycol fatty acid ester, POE alkylamine, POE
Examples thereof include fatty acid amides, sucrose fatty acid esters, POE nonylphenyl formaldehyde condensates, alkylethoxydimethylamine oxide, and trioleyl phosphoric acid.

Examples of other surfactants include anionic surfactants such as fatty acid soaps, higher alkyl sulfates, POE lauryl sulfate triethanolamine, alkyl ether sulfates, alkyltrimethylammonium salts, alkylpyridinium salts, alkyl quaternary salts. Stabilizes cationic surfactants such as ammonium salts, alkyldimethylbenzylammonium salts, POE alkylamines, alkylamine salts, polyamine fatty acid derivatives, and amphoteric surfactants such as imidazoline-based amphoteric surfactants and betaine-based surfactants. And you may mix | blend in the range which does not have a problem in skin irritation.

The moisturizing agent is not particularly limited, and examples thereof include xylitol, sorbitol, maltitol, chondroitin sulfate, hyaluronic acid, mucoitin sulfate, caronic acid, atelocollagen, cholesteryl-12-hydroxystearate, sodium lactate, bile salt, dl- Examples thereof include pyrrolidone carboxylate, short-chain soluble collagen, diglycerin (EO) PO adduct, Izayoi rose extract, yarrow extract, and merirot extract.

The higher alcohol is not particularly limited, and examples thereof include linear alcohols such as lauryl alcohol, cetyl alcohol, stearyl alcohol, behenyl alcohol, myristyl alcohol, oleyl alcohol, cetostearyl alcohol, monostearyl glycerin ether (batyl alcohol), 2-decyl. Examples thereof include branched chain alcohols such as tetradecinol, lanolin alcohol, cholesterol, phytosterol, hexyldodecanol, isostearyl alcohol, octyldodecanol, and the like.

The sequestering agent is not particularly limited. For example, 1-hydroxyethane-1,1-diphosphonic acid, 1-hydroxyethane-1,1-diphosphonic acid tetrasodium salt, sodium citrate, sodium polyphosphate, metaphosphoric acid Examples thereof include sodium, gluconic acid, phosphoric acid, citric acid, ascorbic acid, succinic acid, edetic acid and the like.

The natural water-soluble polymer is not particularly limited, and examples thereof include gum arabic, gum tragacanth, galactan, guar gum, carob gum, caraya gum, carrageenan, pectin, agar, quince seed (malmello), alge colloid (gypsum extract), starch (rice) Corn, potato, wheat), plant polymers such as glycyrrhizic acid, microbial polymers such as xanthan gum, dextran, succinoglucan and pullulan, and animal polymers such as collagen, casein, albumin and gelatin. it can.

The semi-synthetic water-soluble polymer is not particularly limited. For example, starch-based polymers such as carboxymethyl starch and methylhydroxypropyl starch, methylcellulose, nitrocellulose, ethylcellulose, methylhydroxypropylcellulose, hydroxyethylcellulose, sodium cellulose sulfate, Examples thereof include cellulose polymers such as hydroxypropylcellulose, sodium carboxymethylcellulose (CMC), crystalline cellulose, and cellulose powder, and alginic acid polymers such as sodium alginate and propylene glycol alginate.

The synthetic water-soluble polymer is not particularly limited, and examples thereof include vinyl polymers such as polyvinyl alcohol, polyvinyl methyl ether, and polyvinyl pyrrolidone, and polyoxyethylene polymers such as polyethylene glycol 20,000, 40,000, and 60,000. Examples thereof include polymers, copolymer polymers such as polyoxyethylene polyoxypropylene copolymer, acrylic polymers such as sodium polyacrylate, polyethyl acrylate, and polyacrylamide, polyethyleneimine, and cationic polymers.

The inorganic water-soluble polymer is not particularly limited, and examples thereof include bentonite, silicate AlMg (beegum), laponite, hectorite, and silicic anhydride.

The ultraviolet screening agent is not particularly limited. For example, paraaminobenzoic acid (hereinafter abbreviated as PABA), PABA monoglycerin ester, N, N-dipropoxy PABA ethyl ester, N, N-diethoxy PABA ethyl ester, N, N-dimethyl Benzoic acid UV screening agents such as PABA ethyl ester and N, N-dimethyl PABA butyl ester; Anthranilic acid UV screening agents such as homomenthyl-N-acetylanthranylate; Amyl salicylate, menthyl salicylate, homomenthyl salicylate, octyl salicylate , Salicylic acid UV screening agents such as phenyl salicylate, benzyl salicylate, p-isopropanol phenyl salicylate; octylcinnamate, ethyl-4-isopropylcinnamate, methyl-2,5- Isopropyl cinnamate, ethyl-2,4-diisopropyl cinnamate, methyl-2,4-diisopropyl cinnamate, propyl-p-methoxycinnamate, isopropyl-p-methoxycinnamate, isoamyl-p-methoxycinnamate, 2- Ethoxyethyl-p-methoxycinnamate, cyclohexyl-p-methoxycinnamate, ethyl-α-cyano-β-phenylcinnamate, 2-ethylhexyl-α-cyano-β-phenylcinnamate, glyceryl mono-2-ethylhexa Cinnamic acid-based ultraviolet screening agents such as noyl-diparamethoxycinnamate; 2,4-dihydroxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone , 2, 2 ', 4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy-4'-methylbenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonate, 4 -Benzophenone-based UV shielding agents such as phenylbenzophenone, 2-ethylhexyl-4'-phenyl-benzophenone-2-carboxylate, 2-hydroxy-4-n-octoxybenzophenone, 4-hydroxy-3-carboxybenzophenone; (4′-methylbenzylidene) -d, l-camphor, 3-benzylidene-d, l-camphor, urocanic acid, urocanic acid ethyl ester, 2-phenyl-5-methylbenzoxazole, 2,2′-hydroxy- 5-methylphenylbenzotri Sol, 2- (2′-hydroxy-5′-t-octylphenyl) benzotriazole, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, dibenzalazine, dianisoylmethane, 4-methoxy-4 ′ -T-butyldibenzoylmethane, 5- (3,3-dimethyl-2-norbornylidene) -3-pentan-2-one and the like can be mentioned.

Other drug components are not particularly limited and include, for example, vitamin A oil, retinol, retinol palmitate, inosit, pyridoxine hydrochloride, benzyl nicotinate, nicotinamide, nicotinic acid DL-α-tocopherol, magnesium ascorbate phosphate, 2 Vitamins such as -O-α-D-glucopyranosyl-L-ascorbic acid, vitamin D2 (ergocaciferol), dl-α-tocopherol, dl-α-tocopherol acetate, pantothenic acid, biotin; estradiol, ethinylestradiol, etc. Hormones; amino acids such as arginine, aspartic acid, cystine, cysteine, methionine, serine, leucine and tryptophan; anti-inflammatory agents such as allantoin and azulene; whitening agents such as arbutin; astringents such as tannic acid; L Menthol, cooling agents and sulfur camphor such as, lysozyme chloride, can be mentioned pyridoxine chloride, and the like.

There are no particular limitations on the various extracts, for example, Dokudami extract, Oat extract, Merirot extract, Odorikosou extract, Licorice extract, Peonies extract, Soap extract, Loofah extract, Kina extract, Yukinoshita extract, Clara extract, Kouhone extract, Fennel Extract, Primrose Extract, Rose Extract, Giant Extract, Lemon Extract, Shikon Extract, Aloe Extract, Shobu Root Extract, Eucalyptus Extract, Horsetail Extract, Sage Extract, Thyme Extract, Tea Extract, Seaweed Extract, Cucumber Extract, Clove Extract, Raspberry Extract, Melissa Extract , Carrot extract, marronnier extract, peach extract, peach leaf extract, mulberry extract, cornflower extract, hamamelis extract, placenta extract, thymus extract, silk extract, licorice Mention may be made of the kiss and the like.

Examples of the various powders include bengara, yellow iron oxide, black iron oxide, titanium mica, iron oxide-coated mica titanium, titanium oxide-coated glass flakes and other bright colored pigments, mica, talc, kaolin, sericite, titanium dioxide, Examples thereof include inorganic powders such as silica and organic powders such as polyethylene powder, nylon powder, crosslinked polystyrene, cellulose powder, and silicone powder. Preferably, a part or all of the powder component is hydrophobized by a known method with a substance such as silicones, fluorine compounds, metal soaps, oils, acyl glutamates in order to improve sensory characteristics and cosmetic durability. May be used. Moreover, you may mix and use the other zinc oxide particle which does not correspond to this invention.

The tetrahedral and / or tetrahedral pair-like zinc oxide particles of the present invention can also be used as a heat-dissipating filler.
When the tetrahedral and / or tetrahedral pair-like zinc oxide particles of the present invention are used as a heat dissipating filler, either a single use or a combination with another heat dissipating filler can be used. Regardless of whether used alone or in combination with other heat dissipating fillers, the heat dissipating filler of the present invention is 10 to 90% by volume based on the total amount of the heat dissipating composition such as the resin composition and the grease composition. It is preferable to use in proportions.

Moreover, when using the tetrahedral shape and / or tetrahedral pair-like zinc oxide particle of this invention as a heat dissipation filler, it can also be used in combination with the heat dissipation filler from which a particle diameter differs. The heat dissipating filler that can be used in combination is not particularly limited, and examples thereof include metal oxides such as magnesium oxide, titanium oxide, and aluminum oxide, aluminum nitride, boron nitride, silicon carbide, silicon nitride, titanium nitride, and metal silicon. And diamond. Furthermore, it can also be used in combination with zinc oxide other than the round zinc oxide particles described above. The heat dissipating filler used in combination may have an arbitrary shape such as a spherical shape, a needle shape, a rod shape, or a plate shape.

When the tetrahedral and / or tetrahedral pair-like zinc oxide particles are used as a heat dissipating filler, they can be used as a heat dissipating resin composition mixed with a resin. In this case, the resin used may be a thermoplastic resin or a thermosetting resin, and an epoxy resin, a phenol resin, a polyphenylene sulfide (PPS) resin, a polyester resin, polyamide, polyimide, polystyrene, polyethylene, Polypropylene, polyvinyl chloride, polyvinylidene chloride, fluororesin, polymethyl methacrylate, ethylene / ethyl acrylate copolymer (EEA) resin, polycarbonate, polyurethane, polyacetal, polyphenylene ether, polyetherimide, acrylonitrile-butadiene-styrene Examples of the resin include polymer (ABS) resin, liquid crystal resin (LCP), silicone resin, and acrylic resin.

The heat-dissipating resin composition of the present invention comprises (1) a resin composition for thermoforming obtained by kneading a thermoplastic resin and the tetrahedral and / or tetrahedral-pair zinc oxide particles in a molten state. Product, (2) resin composition obtained by kneading the thermosetting resin and the tetrahedral and / or tetrahedral pair-like zinc oxide particles and then heat-curing, (3) resin solution or dispersion It may be a resin composition for paint in which the above tetrahedral and / or tetrahedral pair-like zinc oxide particles are dispersed.

When the heat-dissipating resin composition of the present invention is a resin composition for thermoforming, the resin component can be freely selected depending on the application. For example, when adhering and adhering to a heat source and a heat sink, a resin having high adhesiveness and low hardness such as silicone resin or acrylic resin may be selected.

When the heat radiating resin composition of the present invention is a resin composition for paint, the resin may be curable or non-curable. The paint may be a solvent-based one containing an organic solvent or a water-based one in which a resin is dissolved or dispersed in water.

When the tetrahedral and / or tetrahedral pair-like zinc oxide particles are used as a heat dissipating filler, they can also be used as a heat dissipating grease mixed with a base oil containing mineral oil or synthetic oil. When used as such heat dissipating grease, α-olefin, diester, polyol ester, trimellitic acid ester, polyphenyl ether, alkylphenyl ether and the like can be used as synthetic oil. It can also be used as a heat dissipating grease mixed with silicone oil.

When the tetrahedral and / or tetrahedral pair-like zinc oxide particles of the present invention are used as a heat-dissipating filler, other components can be used in combination. Other components that can be used in combination include metal oxides such as magnesium oxide, titanium oxide, and aluminum oxide, and oxidation of aluminum nitride, boron nitride, silicon carbide, silicon nitride, titanium nitride, metal silicon, diamond, etc. Examples include heat dissipating fillers other than zinc, resins, and surfactants.

The tetrahedral and / or tetrahedral pair-like zinc oxide particles of the present invention can be used in combination with zinc oxide particles having a smaller particle diameter and other heat dissipating fillers to obtain better heat dissipation performance. Can do. The zinc oxide particles having a small particle diameter used in combination are preferably those having a spherical shape, a needle shape, a rod shape, a plate shape, or the like.

The tetrahedral and / or tetrahedral pair-like zinc oxide particles of the present invention include rubber vulcanization accelerators, paint / ink pigments, electrons such as ferrite and varistors, in addition to the cosmetics and heat dissipating fillers described above. It can also be used in the field of parts, pharmaceuticals and the like.

Hereinafter, the present invention will be described in more detail based on examples. In addition, this invention is not limited to a following example.

(Example 1)
116 ml of an aqueous zinc acetate solution prepared by dissolving 32 g of zinc acetate dihydrate (manufactured by Kishida Chemical Co., Ltd., purity: 98%) in water to a concentration of 1.26 mol / l as zinc acetate dihydrate, 195 g of toluene (made by Kishida Chemical Co., Ltd., purity: 99%) to which 14.5 g of AO-15V (manufactured by Kao Corporation, sorbitan sesquioleate, HLB value: 3.7) as an emulsifier (lipophilic dispersant) was added. The mixture was mixed and stirred at high speed for 10 minutes at a rotational speed of 3000 rpm using a homomixer (manufactured by PRIMIX, TK HOMOMIXER MARK II Model 2.5) to obtain a W / O type emulsion. Subsequently, 758 ml of an aqueous sodium hydrogen carbonate solution prepared by dissolving 63.7 g of sodium hydrogen carbonate (manufactured by Wako Pure Chemical Industries, Ltd., purity: 99%) in water to a concentration of 1.0 mol / l as sodium hydrogen carbonate. TW-O120V (manufactured by Kao Corporation, polyoxyethylene sorbitan monooleate, HLB value 14.9), which is an emulsifier (hydrophilic dispersant), was added and mixed well. Subsequently, the aqueous sodium hydrogen carbonate solution is stirred at a rotational speed of 300 rpm with a stirrer, and the emulsion is added thereto to form a W / O / W type emulsion, and the reaction is allowed to proceed by stirring for 30 minutes. It was. After completion of the reaction, the mixture was filtered, washed with water, and dried at 110 ° C. for 12 hours to obtain tetrahedral and tetrahedral paired zinc carbonate salt particles having a median diameter of 13.33 μm. The size and form of the obtained particles were observed with a scanning electron microscope (JSM-5400, manufactured by JEOL Ltd.). The obtained electron micrographs are shown in FIGS. 1 is a photograph of a field of view in which tetrahedral zinc carbonate particles are mainly observed, and FIG. 2 is a photograph of a field of view in which tetrahedral zinc carbonate particles are mainly observed. . The obtained particles were analyzed with an X-ray diffractometer (Ultima III, manufactured by Rigaku Corporation). The obtained X-ray diffraction spectrum is shown in FIG. The evaluation results of the physical properties of the obtained particles are shown in Table 1. In addition, the zinc carbonate salt of Example 1 has a structure of Na ₂ Zn ₃ (CO ₃ ) ₄ (H ₂ O) ₃ having crystal water in the crystal.

(Example 2)
10 g of tetrahedral and tetrahedral paired zinc carbonate particles obtained in Example 1 are placed in an alumina crucible (vertical / horizontal / height = 100 mm / 100 mm / 35 mm), and an electric muffle furnace (manufactured by Toyo Seisakusho). ) To obtain tetrahedral and tetrahedral paired zinc oxide particles having a median diameter of 11.51 μm. The size and form of the obtained particles were observed with a scanning electron microscope (JSM-5400, manufactured by JEOL Ltd.). The obtained electron micrograph is shown in FIG. The X-ray diffraction spectrum of the obtained particles is shown in FIG. Table 1 shows the evaluation results of the physical properties of the obtained particles and the physical properties of the coating film.

(Example 3)
Zinc acetate dihydrate (manufactured by Kishida Chemical Co., Ltd., purity: 98%) 32 g was dissolved in water to prepare 116 ml of an aqueous zinc acetate solution so that the concentration as zinc acetate dihydrate was 1.26 mol / l. Subsequently, 758 ml of an aqueous sodium hydrogen carbonate solution prepared by dissolving 63.7 g of sodium hydrogen carbonate (manufactured by Wako Pure Chemical Industries, Ltd., purity: 99%) in water to a concentration of 1.0 mol / l as sodium hydrogen carbonate. Then, 3.625 g of TW-O120V (manufactured by Kao Corporation, polyoxyethylene sorbitan monooleate, HLB value 14.9) as a hydrophilic dispersant was added and mixed well. Subsequently, the aqueous sodium hydrogen carbonate solution was stirred at a rotation speed of 300 rpm, and the aqueous zinc acetate solution was added thereto and stirred for 10 minutes to proceed the reaction. After completion of the reaction, the mixture was filtered, washed with water, and dried at 110 ° C. for 12 hours to obtain tetrahedral and tetrahedral paired zinc carbonate particles having a median diameter of 14.79 μm. The size and form of the obtained particles were observed with a scanning electron microscope (JSM-5400, manufactured by JEOL Ltd.). The obtained electron micrograph is shown in FIG. The obtained particles were analyzed with an X-ray diffractometer (Ultima III, manufactured by Rigaku Corporation). The obtained X-ray diffraction spectrum is shown in FIG. The evaluation results of the physical properties of the obtained particles are shown in Table 1. In addition, the zinc carbonate salt of Example 3 also has a structure of Na ₂ Zn ₃ (CO ₃ ) ₄ (H ₂ O) ₃ having crystal water in the crystal.

Example 4
10 g of tetrahedral and tetrahedral paired zinc carbonate particles obtained in Example 3 were placed in an alumina crucible (vertical / horizontal / height = 100 mm / 100 mm / 35 mm), and an electric muffle furnace (manufactured by Toyo Seisakusho). ) To obtain tetrahedral and tetrahedral paired zinc oxide particles having a median diameter of 11.35 μm. The size and form of the obtained particles were observed with a scanning electron microscope (JSM-5400, manufactured by JEOL Ltd.). The obtained electron micrograph is shown in FIG. The X-ray diffraction spectrum of the obtained particles is shown in FIG. Table 1 shows the evaluation results of the physical properties of the obtained particles and the physical properties of the coating film.

(Comparative Example 1)
116 ml of an aqueous zinc acetate solution prepared by dissolving 32 g of zinc acetate dihydrate (manufactured by Kishida Chemical Co., Ltd., purity: 98%) in water to a concentration of 1.26 mol / l as zinc acetate dihydrate, 195 g of toluene (made by Kishida Chemical Co., Ltd., purity: 99%) to which 14.5 g of AO-15V (manufactured by Kao Corporation, sorbitan sesquioleate, HLB value: 3.7) as an emulsifier (lipophilic dispersant) was added. The mixture was mixed and stirred at high speed for 10 minutes at a rotational speed of 6000 rpm using a homomixer (manufactured by PRIMIX, TK HOMOMIXER MARK II Model 2.5) to obtain a W / O type emulsion. Subsequently, 80.51 g of sodium carbonate (manufactured by Wako Pure Chemical Industries, Ltd., purity: 99.8%) was dissolved in water to prepare 758 ml of an aqueous sodium carbonate solution prepared so that the concentration as sodium carbonate was 1.0 mol / l. TW-O120V (manufactured by Kao Corporation, polyoxyethylene sorbitan monooleate, HLB value 14.9), which is an emulsifier (hydrophilic dispersant), was added and mixed well. Subsequently, the aqueous sodium carbonate solution was stirred with a stirrer at a rotational speed of 300 rpm, and the emulsion was added thereto to form a W / O / W type emulsion, and the reaction was allowed to proceed by stirring for 30 minutes. . After completion of the reaction, the mixture was filtered, washed with water, and dried at 110 ° C. for 12 hours to obtain spherical zinc carbonate particles having a median diameter of 10.41 μm. The size and form of the obtained particles were observed with a scanning electron microscope (JSM-5400, manufactured by JEOL Ltd.). The obtained electron micrograph is shown in FIG. The obtained particles were analyzed with an X-ray diffractometer (Ultima III, manufactured by Rigaku Corporation). The obtained X-ray diffraction spectrum is shown in FIG. The evaluation results of the physical properties of the obtained particles are shown in Table 1. Incidentally, zinc carbonate of Comparative Example 1 _are those having a _{Zn 5 (OH) 6 (CO} 3) 2 structures.

(Comparative Example 2)
10 g of the spherical zinc carbonate particles obtained in Comparative Example 1 are placed in an alumina crucible (vertical / horizontal / height = 100 mm / 100 mm / 35 mm) and statically kept at 400 ° C. for 3 hours in an electric muffle furnace (manufactured by Toyo Seisakusho). By calcination, spherical zinc oxide particles having a median diameter of 5.83 μm were obtained. The size and form of the obtained particles were observed with a scanning electron microscope (JSM-5400, manufactured by JEOL Ltd.). The obtained electron micrograph is shown in FIG. The X-ray diffraction spectrum of the obtained particles is shown in FIG. Table 1 shows the evaluation results of the physical properties of the obtained particles and the physical properties of the coating film.

(Comparative Example 3)
An aqueous solution prepared by dissolving 150 g of fine zinc oxide (median diameter 0.2 μm, manufactured by Sakai Chemical Industry Co., Ltd.) and 2.085 g of zinc chloride (Kishida Chemical Co., Ltd.) in 300 ml of pure water is placed in a magnetic dish and stirred well to form a slurry. The solid was obtained by evaporating to dryness by heating with stirring. Subsequently, 10 g of the obtained solid material is placed in an alumina crucible (vertical / horizontal / height = 100 mm / 100 mm / 35 mm) and fired at 1150 ° C. for 3 hours in an electric muffle furnace (manufactured by Toyo Seisakusho). Then, amorphous zinc oxide particles having a median diameter of 15.07 μm were obtained. The size and form of the obtained particles were observed with a scanning electron microscope (JSM-5400, manufactured by JEOL Ltd.). The obtained electron micrograph is shown in FIG. The evaluation results of the physical properties of the particles and the physical properties of the coating film are shown in Table 1.

(Evaluation method)
(X-ray diffraction spectrum, composition of the obtained particles)
The spectra of the X-ray diffraction shown in FIGS. 3, 5, 7, 9, 11, and 13 and the composition of the particles obtained in Table 1 were analyzed by an X-ray diffractometer Ultima III (manufactured by Rigaku Corporation) having a copper tube. The results are shown.

(Median diameter and D10, D90, D90 / D10)
In this specification, the median diameter, D90, and D10 are values measured by a laser diffraction / scattering particle size distribution analyzer LA-750 (manufactured by Horiba, Ltd.). Measurement was carried out using 0.5 g of zinc oxide particles of Examples and Comparative Examples dispersed in 50 ml of an aqueous solution of sodium hexametaphosphate having a concentration of 0.025% by weight as sodium hexametaphosphate. The measurement was performed with a circulation speed of 7 at the time of measurement, an ultrasonic dispersion time of 30 seconds, and an ultrasonic intensity of 3. Measured by setting the relative refractive index of the zinc carbonate salt of Examples 1 and 3 and the zinc carbonate of Comparative Example 1 to 1.3, and the relative refractive index of zinc oxides of Examples 2 and 4 and Comparative Examples 2 and 3 to 1.5. went. In this specification, the median diameter means 50% cumulative particle diameter on a volume basis, D90 means 90% cumulative particle diameter on a volume basis, and D10 means 10% cumulative particle diameter on a volume basis. A ratio of D90 / D10 is calculated as an index of the sharpness of the particle size distribution. A larger value means that the particle size distribution is broader, and a smaller value means that the particle size distribution is sharper.

(MIU (mean coefficient of friction))
MIU (average friction coefficient) in Table 1 is a value obtained by measuring the zinc oxide particles obtained in the above Examples and Comparative Examples with a KES-SE friction tester (manufactured by Kato Tech Co., Ltd.). A double-sided tape with a width of 25 mm was applied to the slide glass, the powder was placed, stretched with a cosmetic puff, and MIU (average friction coefficient) was measured with a KES-SE friction tester (manufactured by Kato Tech). Measurement was performed under the conditions of a friction measurement load of 25 gf, a surface measurement sample moving speed of 1 mm / sec, and a measurement distance range of 20 mm. As the sensor, a silicone contactor (silicone rubber friction element with unevenness assuming a human finger) was used. A smaller MIU (average friction coefficient) value means better slipperiness and easier slipping.

(MMD (average deviation of friction coefficient))
The MMD (average deviation of the friction coefficient) in Table 1 is a value obtained by measuring the zinc oxide particles obtained in the above Examples and Comparative Examples with a KES-SE friction tester (manufactured by Kato Tech Co., Ltd.). A 25 mm wide double-sided tape was affixed to a slide glass, the powder was placed, stretched with a cosmetic puff, and MMD (average deviation of friction coefficient) was measured with a KES-SE friction tester (manufactured by Kato Tech). Measurement was performed under the conditions of a friction measurement load of 25 gf, a surface measurement sample moving speed of 1 mm / sec, and a measurement distance range of 20 mm. As the sensor, a silicone contactor (silicone rubber friction element with unevenness assuming a human finger) was used. A smaller value of MMD (average deviation of friction coefficient) means less roughness and higher smoothness.

(Creation of coating film)
2 g of zinc oxide particles obtained in the above examples and comparative examples, 10 g of varnish (manufactured by Acridic A-801-P DIC), 5 g of butyl acetate (manufactured by Wako Pure Chemical Industries, Ltd.), 5 g of xylene (genuine special grade, Junsei Chemical) Glass beads 38g (1.5mm Potters Ballotini) in a mayonnaise bottle with a volume of 75ml, stirred well, fixed to paint conditioner 5410 (RED DEVIL), and vibrated for 90 minutes. A paint was prepared by applying and dispersing. Next, a small amount of the prepared paint is dropped on a slide glass (length, width, thickness = 76 mm, 26 mm, 0.8 to 1.0 mm, manufactured by Matsunami Glass Industrial Co., Ltd.), and a bar coater (No. 579 ROD No. 6). A coating film was prepared by Yasuda Seiki Seisakusho. The prepared coating film was dried at 20 ° C. for 12 hours, and then used for measurement of total light transmittance 1, total light transmittance 2, parallel light transmittance 1, and parallel light transmittance 2.

(Total light transmittance 1, Total light transmittance 2, Parallel light transmittance 1, Parallel light transmittance 2)
In this specification, the total light transmittance 1 (%), the total light transmittance 2 (%), the parallel light transmittance 1 (%), and the parallel light transmittance 2 (%) It is the value measured with the total V-570 (made by JASCO Corporation). The value of total light transmittance 1 (%) is the value of total light transmittance at a wavelength of 310 nm, the value of total light transmittance 2 (%) is the value of total light transmittance at a wavelength of 350 nm, and the parallel light transmittance 1 ( %) Is the value of parallel light transmittance at a wavelength of 500 nm, and the value of parallel light transmittance 2 (%) is the value of parallel light transmittance at a wavelength of 700 nm. It means that the smaller the value of the total light transmittance 1 (%), the higher the ultraviolet shielding effect against the UVB wavelength ultraviolet light, and the smaller the value of the total light transmittance 2 (%), the UVA wavelength against the ultraviolet light. It means that the ultraviolet shielding effect is high. Moreover, it means that visible light transparency is so high that the value of parallel light transmittance 1 (%) and parallel light transmittance 2 (%) is large.

From the results of Table 1, the zinc oxide particles of the present invention have excellent powder feel and excellent visible light transparency by having a unique shape of tetrahedral and / or tetrahedral pairs. Is clear.

The zinc oxide particles of the present invention can be used as cosmetic ingredients, heat dissipating fillers, and the like.

Claims (8)

Tetrahedral and / or tetrahedral pair-like zinc carbonate particles having a median diameter of 0.1 μm to 100 μm. Tetrahedral and / or tetrahedral paired zinc oxide particles having a median diameter of 0.1 μm to 100 μm. The tetrahedral and / or tetrahedral pair-like zinc oxide particles according to claim 2, wherein MIU (average coefficient of friction) is 1.0 or less. The tetrahedral and / or tetrahedral pair-like zinc oxide particles according to claim 2 or 3, wherein D90 / D10 in the particle size distribution is 4.0 or less. The tetrahedral and / or tetrahedral body according to claim 1, comprising a step (1) of neutralizing an aqueous zinc salt solution or an emulsion obtained by emulsifying an aqueous zinc salt solution with an organic solvent with a bicarbonate metal salt. A method for producing paired zinc carbonate particles. Step (1) of neutralizing zinc salt aqueous solution or emulsion obtained by emulsifying zinc salt aqueous solution with organic solvent with metal bicarbonate, and tetrahedral and / or tetrahedral pairs obtained by step (1) The method for producing tetrahedral and / or tetrahedral paired zinc oxide particles according to claim 2, 3 or 4, comprising a step (2) of thermally decomposing the zinc carbonate salt particles by firing. A heat dissipating filler comprising the tetrahedral and / or tetrahedral paired zinc oxide particles according to claim 2, 3 or 4. A cosmetic comprising the tetrahedral and / or tetrahedral paired zinc oxide particles according to claim 2, 3 or 4.