cosmetic

Abstract

The present invention relates to a cosmetic containing fatty acid magnesium salt particles and mica, wherein the carbon number of the fatty acid in the fatty acid magnesium salt particles is 12 to 22, the aspect ratio represented by the following formula (1) is 1.0 to 2.0, the average thickness is 250 to 600 nm, and the aspect ratio = major axis diameter of the particle (μm) / minor axis diameter of the particle (μm)...Formula (1).

Description

Technical Field

[0001] The present invention relates to cosmetics compounded with magnesium fatty acid. Background Art

[0002] In order to maintain the dosage form of cosmetics, a method of adding an extender pigment is known. The extender pigment is also expected to adjust the spreadability, adhesion, gloss, etc., and function as a diluent for adjusting the color tone.

[0003] As extender pigments, inorganic pigments and organic pigments are known, and mica is known as one of the inorganic pigments (Patent Documents 1 and 2).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2013-234133

[0007] Patent Document 2: Japanese Patent Application Publication No. 2006-199645 Summary of the invention

[0008] Problem that the invention aims to solve

[0009] Mica is blended in the hope of improving the usability, but due to its plate-like particle shape, the blending amount becomes large, resulting in an excessive glossiness, making it difficult to achieve a natural finish.

[0010] An object of the present invention is to provide a novel cosmetic having good usability, excellent product appearance, and exhibiting a natural facial makeup effect when applied.

[0011] Solutions for solving problems

[0012] As a result of intensive research, the inventors of the present invention have found that the above-mentioned problems can be solved by including fatty acid magnesium salt particles having a specific aspect ratio and average thickness and mica. That is, the cosmetic of the present invention is as follows.

[0013] [1] A cosmetic comprising fatty acid magnesium salt particles and mica, wherein:

[0014] The carbon number of the fatty acid in the aforementioned fatty acid magnesium salt particles is 12 to 22,

[0015] The fatty acid magnesium salt particles have an aspect ratio represented by the following formula (1) of 1.0 or more and 2.0 or less,

[0016] The average thickness of the aforementioned fatty acid magnesium salt particles is 250 to 600 nm.

[0017] Aspect ratio=long axis diameter of particle (μm) / short axis diameter of particle (μm)...Formula (1).

[0018] [2] The cosmetic according to [1], wherein the content of the mica is 5% by mass or more.

[0019] [3] The cosmetic according to [1] or [2], wherein the mica comprises synthetic fluorphlogopite.

[0020] [4] The cosmetic according to any one of [1] to [3], wherein the average particle size of the mica is 15 μm or less.

[0021] Effects of the Invention

[0022] According to the present invention, a cosmetic can be provided in which, by maintaining the aspect ratio and thickness and mixing fatty acid magnesium salt particles having a specific aspect ratio and a specific thickness into a formulation, the fatty acid magnesium salt particles sparkle in the product form, but the fatty acid magnesium disintegrates and becomes smaller after application, and the fatty acid magnesium eliminates the unnatural luster of mica and exhibits natural makeup properties. DETAILED DESCRIPTION

[0023] The cosmetic of the present invention contains specific fatty acid magnesium salt particles as metal soap.

[0024] The fatty acid magnesium salt particles of the present invention are formed from a divalent fatty acid magnesium salt having a carbon number of 12 to 22. The particles can be prepared by a double decomposition method in which a fatty acid alkali compound salt is reacted with a divalent magnesium salt in an aqueous solution, wherein the fatty acid alkali compound salt is obtained by reacting a fatty acid having a carbon number of 12 to 22 with a monovalent alkali compound.

[0025] The fatty acid used as the raw material of the fatty acid alkali compound salt is not particularly limited as long as it is a fatty acid having 12 to 22 carbon atoms. That is, it can be either naturally derived fatty acids or synthetic fatty acids, either saturated fatty acids or unsaturated fatty acids, and either straight-chain or branched. Furthermore, the structure of the fatty acid can also contain functional groups such as hydroxyl, aldehyde, and epoxy groups. As the fatty acid, a straight-chain saturated fatty acid is preferred.

[0026] In addition, when the carbon number of the fatty acid is 12 or more, excellent usability can be imparted to the cosmetics. On the other hand, when the carbon number is 22 or less, it is easy to obtain as a fatty acid from industry, and the solubility of the obtained fatty acid alkali compound salt in water does not decrease significantly, so the productivity is high. The carbon number of the fatty acid is preferably 12 to 18, and more preferably 14 (i.e., the fatty acid magnesium is magnesium myristate).

[0027] As fatty acid, for example, lauric acid, myristic acid, myristic acid, palmitic acid, palmitoleic acid, stearic acid, oleic acid, linoleic acid, arachidic acid, behenic acid, erucic acid, hydroxystearic acid and epoxystearic acid etc. can be mentioned, among which myristic acid is preferred. When using mixed fatty acid, the myristic acid content in the fatty acid is preferably 50% or more, more preferably 60% or more, and further preferably 70% or more.

[0028] The fatty acid magnesium salt particles of the present invention have an aspect ratio of 1.0 to 2.0, preferably 1.0 to 1.6, and more preferably 1.0 to 1.5.

[0029] In the present invention, the aspect ratio of particles refers to the value obtained by dividing the major axis diameter of the fatty acid magnesium salt particles by the minor axis diameter (=major axis diameter / minor axis diameter) represented by the following formula (1).

[0030] Aspect ratio = major axis diameter of particle (μm) / minor axis diameter of particle (μm) ····Formula (1)

[0031] The closer the aspect ratio is to 1.0, the closer the shape of the particle is to a square or a circle. The fatty acid magnesium salt particles of the present invention preferably have a shape close to a square.

[0032] This improves the spreadability on the skin and provides excellent usability.

[0033] It should be noted that the "major axis diameter" of a particle is the length of the major axis of the particle, more specifically, it is equivalent to the width of the particle with the largest interval between two parallel lines sandwiching the particle. The "minor axis diameter" of a particle is the length of the minor axis of the particle, more specifically, it is equivalent to the width of the particle measured by a straight line passing through the midpoint of the major axis and intersecting the major axis perpendicularly. It should be noted that the average thickness of a particle refers to the average value obtained by measuring the length of the side surface when the surface with the largest area in the fatty acid magnesium salt particle is the front side for 10 particles. The average thickness of a particle is a value measured based on a two-dimensional projection image (specifically, a SEM photo) of the particle.

[0034] In addition, the average thickness of the particles of the fatty acid magnesium salt particles of the present invention is 250 to 600 nm. By setting the thickness to this, it is easy to break even under mild mixing conditions (manufacturing method) for cosmetics, and can be evenly applied to the skin as a cosmetic, and the makeup and touch after application can also be improved. In addition, when the thickness is an average of 250 nm or more, when added to cosmetics, the handling of the fatty acid magnesium salt particles is good, and there is no worry about reduced operability. The average thickness of the particles is more preferably 280 to 450 nm, and particularly preferably 300 to 450 nm. If 300 to 450 nm is met, the effect of the present invention can be obtained more stably.

[0035] The cosmetics of the present invention contain the fatty acid magnesium salt particles having the above-mentioned specific properties, and thus have excellent product appearance. Specifically, the light reflected by the cosmetic surface is in a state of glittering light (referred to as a dot feeling in the present invention). It is presumed that this is because the aspect ratio is specific, i.e., the shape is close to a square, and the thickness of the particles is small, so the particle surface is easily specularly reflected, which can give the cosmetics a beautiful luster.

[0036] In addition, the cosmetic of the present invention contains the fatty acid magnesium salt particles having the above-mentioned specific properties, and is excellent in usability. This is presumably because the fatty acid magnesium salt particles in the present invention have a specific aspect ratio, thereby improving the spreadability on the skin.

[0037] In addition, the fatty acid magnesium of the present invention is a soft metal soap, so it is easy to disintegrate when applied to the skin, and the particle size becomes small. Therefore, it is difficult to produce specular reflection after application, thereby suppressing unnecessary gloss and achieving natural makeup. In this way, when the cosmetics of the present invention containing fatty acid magnesium having a specific aspect ratio and thickness are applied, the gloss changes, thereby suppressing the unnecessary gloss of mica and achieving natural makeup.

[0038] Furthermore, the particle index of the fatty acid magnesium salt particles of the present invention is preferably 1.5 or more and 8.0 or less. By using this particle index, the cosmetic can be evenly applied to the skin, and the touch after application can also be maintained for a long time. In addition, when the particle index is 1.5 or more, when the fatty acid magnesium salt particles are added to the cosmetic, the dispersibility is good, and there is no worry about reduced operability. The particle index of the particles is preferably 1.5 or more and 6.0 or less, more preferably 2.0 or more and 5.0 or less. If it satisfies 2.0 or more and 5.0 or less, the effect of the present invention can be obtained more stably.

[0039] It should be noted that in the present invention, the particle index of the particles refers to the following formula (2), that is, the value obtained by dividing the major axis diameter of the fatty acid magnesium salt particles by the minor axis diameter (=major axis diameter / minor axis diameter) by the average thickness of the particles [=(major axis diameter / minor axis diameter) / average thickness of the particles].

[0040] Particle index = [(major axis diameter of particle (μm) / minor axis diameter of particle (μm)) / average thickness of particle (nm)] × 1000····Formula (2)

[0041] Furthermore, the fatty acid magnesium salt particles of the present invention have a narrow particle size distribution, so that they can be uniformly present in the cosmetic, and the effects of the present invention (especially the improvement of the touch of the cosmetic) can be more stably exerted. Specifically, the median particle size of the fatty acid magnesium salt particles is preferably 10.0 to 40.0 μm, and the particle size description value A represented by the following formula (3) is preferably set to 2.5 or less.

[0042] Particle size description value A = (D90-D10) / D50...Formula (3)

[0043] (where 10.0≤D50≤40.0)

[0044] D10: 10% cumulative particle size based on volume of fatty acid magnesium salt particles (μm)

[0045] D50: Median particle size of fatty acid magnesium salt particles based on volume (μm)

[0046] D90: 90% cumulative particle size based on volume of fatty acid magnesium salt particles (μm)

[0047] The particle size description value A of the present invention is calculated based on the particle size measured by the Microtrac laser diffraction method. When the particle size description value A is less than 2.5, the particle size of the fatty acid magnesium salt particles present in the cosmetic becomes uniform, the dispersibility of the cosmetic is good, the productivity is not reduced, and the cosmetics with the desired touch can be manufactured. The particle size description value A more preferably satisfies the relationship of 0.5≤A≤2.5. When the relationship of 0.5≤A≤2.5 is satisfied, the effect of the present invention is more stably obtained. If the particle size description value A is more than 0.5, the yield rate will not be reduced, and it can be stably manufactured industrially.

[0048] It should be noted that when the cumulative curve is obtained with the total volume of the powder group of the above formula (3) as 100%, the particle sizes at the 10%, 50%, and 90% points of the cumulative curve are respectively referred to as the 10% cumulative particle size (D10), the 50% median particle size (D50; median particle size), and the 90% cumulative particle size (D90) (μm). It should be noted that the particle size means the particle size of the primary particle. When the particles aggregate during measurement, the measurement is performed in a state where they are dispersed using ultrasound or the like.

[0049] The particle size description value A can be adjusted by appropriately adjusting the concentration of the fatty acid alkali compound salt, the temperature of the reaction of the fatty acid alkali compound salt and the magnesium salt, and the dripping speed when the magnesium salt-containing aqueous solution is dripped into the fatty acid alkali compound salt aqueous solution. In addition, for those with a wide particle size distribution, that is, a large value of the particle size description value A, in the post-treatment, it can be carried out by sieving using 100 mesh, 200 mesh, 330 mesh, etc.

[0050] The Microtrac laser diffraction method used here is a method of obtaining the particle size distribution by utilizing the scattered light obtained by irradiating the particles with laser. In the present invention, an organic solvent such as ethanol, isopropanol, etc., which makes the fatty acid magnesium salt particles insoluble, is circulated and a sample is put into the wet measurement. In addition, the particle size of the measurement object in the present invention is in the range of 0.1μm to 200μm, and the value shown in the above formula (3) is the particle size description value A. It should be noted that in the present invention, for example, Microtrac MT-3000 manufactured by Nikkiso Co., Ltd. can be used for measurement.

[0051] In the fatty acid magnesium salt particles of the present invention, the median particle size (D50) on a volume basis is preferably 10.0 to 40.0 μm. By setting the particle size to this, the feel during use is good. The median particle size of the fatty acid magnesium salt particles is preferably 13.0 to 35.0 μm, more preferably 15.0 to 25.0 μm. It should be noted that the particle size can be measured by the Microtrac laser diffraction method, similar to the particle size description value A described above.

[0052] The shape of the fatty acid magnesium salt particles of the present invention is not particularly limited, but is preferably in a plate shape from the viewpoint of usability.

[0053] In order to obtain the fatty acid magnesium salt particles satisfying the above-mentioned specific properties, the particles can be prepared by a double decomposition method in which a fatty acid alkali compound salt is reacted with a divalent magnesium salt in an aqueous solution, wherein the fatty acid alkali compound salt is obtained by reacting a fatty acid having 12 to 22 carbon atoms with a monovalent alkali compound. Then, when the magnesium salt aqueous solution and the fatty acid alkali compound salt aqueous solution prepared separately are mixed in the double decomposition reaction, the magnesium salt aqueous solution is preferably slowly added dropwise to the fatty acid alkali compound salt aqueous solution as described later.

[0054] As the monovalent alkali compound as the raw material of the fatty acid alkali compound salt, there can be mentioned hydroxides of alkali metals (sodium, potassium, etc.), and amines such as ammonia, monoethanolamine, diethanolamine, triethanolamine, etc. In view of high solubility in water when the fatty acid alkali compound salt is prepared, hydroxides of alkali metals such as sodium and potassium are preferred.

[0055] The fatty acid alkali compound salt used in the present invention is obtained by reacting a monovalent alkali compound with a fatty acid, usually at a temperature above the melting point of the fatty acid and at a temperature at which the fatty acid does not decompose, preferably 100° C. or less, more preferably 50 to 100° C., further preferably 60 to 95° C., and particularly preferably 80 to 95° C.

[0056] The fatty acid magnesium salt particles of the present invention can be obtained, for example, by reacting the fatty acid alkali compound salt obtained above with a magnesium salt in an aqueous solution. Specifically, the magnesium salt is a salt of inorganic magnesium and an inorganic acid or an organic acid. Examples of the magnesium salt include magnesium chloride, magnesium sulfate, and magnesium acetate. In particular, magnesium chloride and sulfate are preferred because of their high solubility in water and their efficient reaction with the fatty acid alkali compound salt.

[0057] The reaction of the fatty acid alkali compound salt and the divalent magnesium salt is specifically carried out by separately preparing an aqueous solution containing a magnesium salt and an aqueous solution containing a fatty acid alkali compound salt and then mixing them. For example, the reaction is carried out by adding the aqueous solution containing a magnesium salt to the aqueous solution containing a fatty acid alkali compound salt or by adding both to another reaction tank.

[0058] When the fatty acid alkali compound salt solution and the magnesium salt solution are mixed, for example, when the magnesium salt solution is added to the fatty acid alkali compound salt solution at once, the shape of the obtained fatty acid magnesium salt particles will be uneven, and there is a concern that the aspect ratio of the particles will increase. Therefore, in the present invention, it is preferred to drop the magnesium salt solution at an appropriate speed relative to the fatty acid alkali compound salt solution.

[0059] The preferred dropping speed per unit time is 0.005 to 0.8 mol / min, more preferably 0.01 to 0.5 mol / min. By mixing with this dropping speed, the exchange reaction of alkali and magnesium can be carried out smoothly, and fatty acid magnesium salt particles with appropriate aspect ratio and thickness can be obtained. By this speed being more than 0.005 mol / min, fatty acid magnesium salt particles with desired aspect ratio and thickness can be obtained. On the other hand, by the dropping speed per unit time being less than 0.8 mol / min, the shape of uniform fatty acid magnesium salt particles is formed, and the particles become desired aspect ratio and thickness, so the particle size is not uneven and the particle size is good.

[0060] The unit "mol / min" of the magnesium salt added dropwise is the number of moles of the magnesium salt added dropwise per unit time relative to 1 mol of the fatty acid base compound.

[0061] From the productivity of the fatty acid magnesium salt and the handling of the fatty acid alkali compound salt aqueous solution or the obtained fatty acid magnesium salt slurry, the concentration of the fatty acid alkali compound salt when manufacturing the fatty acid magnesium salt is usually 1% to 20% by mass, preferably 5% to 15% by mass. If the concentration of the fatty acid alkali compound salt is 1% by mass or more, the productivity of the fatty acid magnesium salt is good, so it is preferred. If it is 20% by mass or less, the viscosity of the fatty acid alkali compound salt aqueous solution or the obtained fatty acid magnesium salt slurry will not increase, and a uniform reaction can be carried out. It should be noted that from the productivity of the fatty acid magnesium salt and the handling of the fatty acid alkali compound salt aqueous solution or the obtained fatty acid magnesium salt slurry, the concentration of the magnesium salt in the magnesium salt aqueous solution is usually 10% to 50% by mass, preferably 10% to 40% by mass.

[0062] Considering the solubility of the fatty acid alkali compound salt, the reaction of the fatty acid alkali compound salt and the magnesium salt is carried out under the temperature conditions commonly carried out by those skilled in the art. Preferably, it is 50 to 100° C., more preferably 60 to 95° C. If the reaction temperature is 50° C. or higher, the reaction rate of the fatty acid alkali compound salt and the magnesium salt is good.

[0063] When the fatty acid alkali compound salt reacts with the magnesium salt, the purpose is to stabilize the fatty acid magnesium salt slurry and improve the productivity of the fatty acid magnesium salt. It is preferred that a polyalkylene glycol ether, particularly a triblock ether having a structure (EO-PO-EO) in which an oxypropylene block is sandwiched by an oxyethylene block, is present in the fatty acid magnesium salt slurry. Usually, the content of the polyalkylene glycol ether in the fatty acid magnesium salt slurry is 0.01 to 5 parts by mass, preferably 0.05 to 2 parts by mass, relative to 100 parts by mass of the fatty acid alkali compound salt. It should be noted that the polyalkylene glycol ether may be present in the reaction system before the monovalent base compound reacts with the fatty acid, and may also be present in the reaction system before the fatty acid alkali compound salt reacts with the magnesium salt.

[0064] By this method, a fatty acid magnesium salt filter cake with reduced water content is obtained by separation using a dehydrator, filter press, etc. The fatty acid magnesium salt filter cake with reduced water content is dried using a rotary dryer, an airflow drying device, a ventilated plate dryer, a vacuum plate dryer, a spray dryer, a fluidized bed drying device, etc.

[0065] In the present invention, for the drying of the fatty acid magnesium salt filter cake, it is necessary to dry at (α-60)°C ≤ α ≤ (α-30)°C relative to the water evaporation peak top temperature (α°C) of the generated fatty acid magnesium salt. Here, the water evaporation peak top temperature refers to the peak of the temperature range in which the residual water contained in the fatty acid magnesium salt that cannot be removed by the above-mentioned drying begins to escape. For example, in the heat absorption chart of magnesium myristic acid based on differential thermal analysis (DSC), the water evaporation peak top temperature is 102.1°C. The specific drying temperature varies depending on the type of fatty acid magnesium salt obtained. For example, in the case of magnesium myristic acid, it is 72°C or less. When the drying treatment is carried out at a temperature higher than 72°C, condensation occurs between the fine particles, and the thickness of the particles tends to increase. On the other hand, when the drying treatment is carried out at a temperature lower than 40°C, the drying property is reduced, a large amount of water tends to remain in the compound, and there is a concern that the productivity will be reduced.

[0066] The fatty acid magnesium salt particles can be produced as described above.

[0067] The content of the magnesium fatty acid in the cosmetic of the present invention is preferably 1 to 30% by mass, more preferably 5 to 30% by mass, from the viewpoint of the aesthetic appearance of the preparation and eliminating the unnatural luster of mica.

[0068] The cosmetic of the present invention further comprises mica. Thus, the usability of the cosmetic becomes good. The usability here specifically means that the feel during application is smooth and good.

[0069] From the viewpoint of exerting natural makeup properties during application, the mica preferably has a small particle size, and the average particle size is preferably 15 μm or less, and from the viewpoint of natural makeup properties, the average particle size is more preferably 10 μm or less.

[0070] It should be noted that the average particle size can be measured, for example, using a laser diffraction / scattering particle size distribution analyzer, and is referred to as D50.

[0071] As mica, natural mica, synthetic fluorphlogopite, and synthetic fluorphlogopite iron are preferred from the viewpoint of better usability, and synthetic fluorphlogopite is particularly preferred. These can be used alone or in combination of two or more.

[0072] From the viewpoint of smooth feel during use, the content of mica in the cosmetic of the present invention is preferably 5% by mass or more, preferably 5% by mass to 50% by mass, and more preferably 15% by mass to 35% by mass.

[0073] The cosmetic of the present invention may further contain inorganic powders and organic powders.

[0074] Examples of the inorganic powder include inorganic pigments such as zinc oxide, red iron oxide, yellow iron oxide, and black iron oxide, mica, and talc.

[0075] Examples of the organic powder include organic pigments such as natural pigments.

[0076] Furthermore, these powders may be surface-treated with fluorine compounds, silicone compounds, fatty acids, and the like.

[0077] Furthermore, the cosmetic of the present invention may further contain an oily component.

[0078] Examples of the oily component include liquid oily components and solid oily components. When the cosmetic of the present invention is used as a powdery cosmetic, a liquid oily component is preferred from the viewpoint of reducing powder aggregation and product stability.

[0079] Examples of the liquid oily component include silicone oil, avocado oil, camellia oil, macadamia nut oil, corn oil, olive oil, rapeseed oil, egg yolk oil, sesame oil, peach kernel oil, wheat germ oil, camellia oil, castor oil, linseed oil, safflower oil, cottonseed oil, perilla seed oil, soybean oil, peanut oil, tea seed oil, coconut oil, rice bran oil, paulownia oil, Japanese tung oil, jojoba oil, germ oil, triglycerol, tricaprylin, triisopalmitin, etc. These may also be used in combination of two or more.

[0080] As solid oily components, for example, hydrocarbons / waxes / waxes such as paraffin wax, ozokerite, microcrystalline wax, polyethylene wax, solidified oil, beeswax, wood wax, spermaceti, candelilla wax, higher fatty acids such as stearic acid, lauric acid, myristic acid, behenic acid, higher alcohols such as cetyl alcohol, stearyl alcohol, lauryl alcohol, etc. can be mentioned. These can also be used in combination of two or more.

[0081] From the viewpoint of product stability and usability, the content of the oily component in the cosmetic is preferably 1 to 15% by mass, more preferably 5 to 10% by mass.

[0082] In the cosmetics of the present invention, in addition to the above-mentioned ingredients, other ingredients may be blended according to the purpose within the range of quantity and quality that do not impair the effects of the present invention. For example, pigments, pH adjusters, humectants, thickeners, surfactants, dispersants, stabilizers, colorants, preservatives, antioxidants, masking agents, astringents, anti-inflammatory agents, ultraviolet absorbers, fragrances, other pigments, etc. may also be appropriately blended within the range of achieving the purpose of the present invention.

[0083] The cosmetic of the present invention may be used in any form such as powder, powder solid, cream, emulsion, lotion, oily liquid, oily solid, or paste.

[0084] As for the use of cosmetics, for example, it can be made into makeup cosmetics, skin care cosmetics, hair care cosmetics, etc., such as primer, foundation, concealer, loose powder, face-correcting primer, sunscreen cosmetics, lipstick, lip balm, eye shadow, eyeliner, mascara, blush, nail polish, talcum powder, scented powder, baby powder, etc.

[0085] Example

[0086] The present invention will be described in further detail below with reference to Examples, but the present invention is not limited thereto. The amount of a component to be added is expressed as % by mass relative to the system in which the component is added unless otherwise specified.

[0087] [Preparation of magnesium myristic acid 1]

[0088] 500 g of myristic acid (NAA-142 manufactured by NOF Corporation) and 5600 g of water were added to a 10 L separatory bottle and heated to 90°C. Then, 250.0 g of a 48% by mass sodium hydroxide aqueous solution was added and stirred at the same temperature (90°C) for 1 hour to obtain a fatty acid alkali compound salt aqueous solution. After that, 750.0 g of a 22% by mass magnesium sulfate aqueous solution was added dropwise to the myristic acid sodium salt aqueous solution while maintaining 90°C for 40 minutes [dropping rate: 0.016 (mol / min)]. After the addition was completed, 90°C was maintained and stirred for 30 minutes for aging. The obtained fatty acid magnesium salt aqueous solution slurry was cooled to below 65°C. After that, it was filtered with a suction filter, washed 8 times with 1000 g of water, and the obtained filter cake was dried at 60°C using a ventilated plate dryer and crushed with a mill to obtain myristic acid magnesium salt particles.

[0089] [Preparation of magnesium myristic acid 2]

[0090] In a 3L separatory bottle, add 200g of myristic acid (NAA-142 manufactured by NOF Corporation), 1.00g of polyethylene glycol / polypropylene glycol / block ether (manufactured by NOF Corporation, trade name: PLONON#104) and 2500g of water, and heat to 80°C. Then, add 73.6g of 48% by mass sodium hydroxide aqueous solution, stir at the same temperature (80°C) for 30 minutes to obtain an aqueous solution of sodium myristic acid salt. After that, keep the temperature at 80°C, and add 253.8g of 22% by mass magnesium sulfate aqueous solution to the aqueous solution of sodium myristic acid salt dropwise over 40 minutes [drop speed: 0.013 (mol / min)]. After the addition is completed, keep 80°C, stir for 30 minutes to mature. The obtained fatty acid magnesium salt aqueous solution slurry is naturally cooled to below 60°C. Thereafter, the mixture was filtered with a suction filter and washed twice with 1000 g of water. The filter cake obtained was dried at 60° C. using a ventilated plate dryer and crushed with a mill to obtain myristic acid magnesium salt particles.

[0091] [Evaluation of Magnesium Myristic Acid Granules]

[0092] For magnesium myristic acid salt granules 1 and 2, the median particle size, particle size description value A [value calculated based on the 10% cumulative particle size D10 (μm) on a volume basis, the median particle size D50 (μm) on a volume basis, and the 90% cumulative particle size D90 (μm) on a volume basis], average thickness, major axis diameter, minor axis diameter, and aspect ratio of the particles were measured using the following apparatus according to the above method.

[0093] (1) Particle size description value A, median particle size

[0094] Collect 2.0 g of sample in a 100 ml glass beaker, add 3-5 ml of nonionic surfactant (e.g., Nonio NS-210 manufactured by NOF Corporation) dropwise, and spread evenly with a spatula. Then, add 20 ml of purified water, disperse it by ultrasonic wave, and prepare 100 ml to prepare a measurement sample. The sample is supplied to a particle size distribution measuring device (equipment name "Microtrac MT-3000" manufactured by Nikkiso Co., Ltd.) for measurement (principle: laser diffraction / scattering method).

[0095] When the cumulative curve is obtained with the total volume of the measured powder group as 100%, the particle sizes at the points where the cumulative curve becomes 10%, 50%, and 90% are respectively obtained as the 10% diameter (D10), 50% diameter (D50; median diameter), and 90% diameter (D90) (μm). The particle size description value A is obtained based on the obtained D10, D50, and D90.

[0096] (2) Average particle thickness, major axis diameter, minor axis diameter, aspect ratio, and particle index

[0097] The thickness of the particles was measured by the following method using a scanning electron microscope. After the fatty acid magnesium salt particles were bonded to a carbon double-sided tape, a sample with platinum particles coated on the particle surface by a vapor deposition method was observed at an accelerating voltage of 1.0 kV and a magnification of 2000 times, and the thickness of any particle was measured. The thickness, major axis diameter, and minor axis diameter were calculated for any 10 particles. In addition, the aspect ratio and particle index were calculated using the following formulas.

[0098] Particle index = [(major axis diameter (μm) / minor axis diameter (μm)) / average thickness of particles (nm)] × 1000 Aspect ratio = major axis diameter (μm) / minor axis diameter (μm)

[0099] The above measurement results are shown below.

[0100] <Properties of Magnesium Myristic Acid Granules 1>

[0101] Aspect ratio: 1.4

[0102] Particle index: 4.7

[0103] D10: 11.4μm

[0104] D50: 25.3μm

[0105] D90: 54.9μm

[0106] Average thickness of particles: 309nm

[0107] Particle size description value A: 1.7

[0108] <Properties of Magnesium Myristic Acid Granules 2>

[0109] Aspect ratio: 1.0

[0110] Particle index: 2.4

[0111] D10: 9.8μm

[0112] D50: 19.1μm

[0113] D90: 34.0μm

[0114] Average thickness of particles: 424nm

[0115] Particle size description value A: 1.3

[0116] 〔Magnesium myristate 3〕

[0117] For comparison, magnesium myristic acid (manufactured by Taihei Chemical Industry Co., Ltd.) having an aspect ratio of 2.52 and a median particle size (D50) of 17 μm was prepared.

[0118] <Examples 1 to 6, Comparative Example 1: Pressed Powder>

[0119] Pressed powders having the compositions shown in Table 1 were prepared according to the following production method.

[0120] Manufacturing method: Use a Henschel mixer to mix the powder except the oil and magnesium myristic acid. After adding the oil, mix again with a mixer. After mixing, use a pulverizer to pulverize. Then, return to the mixer to add magnesium myristic acid and mix slowly. Fill the obtained mixture into a medium dish and shape it.

[0121] (Usability Evaluation)

[0122] The cosmetics (pressed powder) obtained by the present invention were evaluated for appearance, feeling during use, etc. based on the following criteria.

[0123] (1) Appearance

[0124] Five expert judges evaluated the appearance of the product in the following manner, and the appearance was evaluated as good in the case of 3 to 5. It should be noted that the meaning of the point feeling is that the surface is more shiny than reflective.

[0125] 5: The sense of point is very strong

[0126] 4: Strong sense of point

[0127] 3: Slightly feel

[0128] 2: Almost no point feeling

[0129] 1: No sense of point

[0130] (2) Smooth feel

[0131] Five expert assessors evaluated the smoothness of the cosmetic when applied to the skin as follows, and the cases with a score of 3 to 5 were evaluated as having good smoothness.

[0132] 5: Very smooth

[0133] 4: Smoother

[0134] 3: Smooth

[0135] 2: Almost not smooth

[0136] 1: Not smooth

[0137] (3) Natural makeup

[0138] Five expert judges evaluated the makeup after applying the cosmetics on the skin as follows, and the cases with a score of 3 to 5 were evaluated as having a natural makeup appearance.

[0139] 5: The makeup is very natural

[0140] 4: Natural makeup

[0141] 3: Natural makeup

[0142] 2: The makeup looks slightly unnatural

[0143] 1: Unnatural makeup

[0144] [Table 1]

[0145]

[0146] (*1)PDM-FE made by Topy Industries, Ltd.

[0147] (*2) PDM-5L manufactured by Topy Industries, Ltd.

[0148] (*3) PDM-10L manufactured by Topy Industries, Ltd.

[0149] (*4)Y-1800 manufactured by Yamaguchi Mica Co., Ltd.

[0150] (*5) SUTINIA M-5 manufactured by JGC Catalysts & Chemicals Co., Ltd.

[0151] The above results show that the cosmetics containing magnesium myristic acid salt particles having specific properties and mica are excellent in appearance and feeling during use.

[0152] <Example 7: Loose Powder>

[0153] Loose powders having the compositions shown in Table 2 were prepared according to the following production method.

[0154] Production method: Use a mixer to mix the powders other than magnesium myristic acid. Add magnesium myristic acid to the mixed powders and mix slowly. Fill the resulting mixture into a mesh container.

[0155] The same evaluation as in Example 1 was performed. The results are shown in Table 2 below.

[0156] [Table 2]

[0157]

[0158] (*2) PDM-5L manufactured by Topy Industries, Ltd.

[0159] As shown in the above table, it can be seen that the cosmetics containing magnesium myristate and mica (Mica) having specific properties are excellent in appearance and usability, and also excellent in makeup properties during application.

[0160] The present invention is described in detail with reference to specific embodiments, but it is clear to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. This application is based on Japanese patent application (Japanese patent application 2020-164364) filed on September 30, 2020, and its contents are incorporated herein by reference.

Claims

1. A cosmetic comprising fatty acid magnesium salt particles and mica, wherein: The carbon number of the fatty acid in the fatty acid magnesium salt particles is 12 to 22, The fatty acid magnesium salt particles have an aspect ratio represented by the following formula (1) of 1.0 or more and 2.0 or less. The content of the fatty acid magnesium salt particles is 1-30% by mass. The average thickness of the fatty acid magnesium salt particles is 250-600 nm. The average particle size of the mica is less than 15 μm, Aspect ratio=long axis diameter of particle (μm) / short axis diameter of particle (μm)····Formula (1).

2. The cosmetic according to claim 1, wherein The content of the mica is 5 mass % or more.

3. The cosmetic according to claim 1 or 2, wherein: The mica comprises synthetic fluorophlogopite.

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