JP6640888B2 - Manufacturing method of powder cosmetics - Google Patents

Description

  The present invention relates to a method for producing a powder cosmetic.

Powder cosmetics are manufactured by mixing powder and oily components, crushing the mixture with a crusher such as a pulverizer, and then filling the mixture in a metal or resin middle plate, or by dry press molding. A method referred to as a dry manufacturing method has been adopted and manufactured.
On the other hand, since properties such as feeling of use are not sufficient according to the dry manufacturing method, for the purpose of improving properties, a slurry is prepared by adding powder and an oily component to a volatile solvent, and the slurry is placed in a container in a slurry state. A method called a wet process has been proposed in which the powder is filled and then the solvent is removed by vacuum suction or the like to solidify the powder.

  As described above, the dry process leaves room for improvement in the feeling of use in application to the skin, and the wet process has room for improvement in removing the solid cosmetics into puffs because they are too hard. In the method, further improvement was required in order to obtain a satisfactory solid cosmetic.

In view of the above problems, attention is paid to the step of drying the slurry in the wet manufacturing method, the slurry is made into fine droplets by mechanical shearing force, the drying gas is sent to the fine droplets, and the slurry is dried, A method for obtaining a powder cosmetic excellent in both usability and usability has been disclosed (see Patent Document 1).
In addition, in the wet manufacturing method, in order to obtain powder solid cosmetics with excellent usability and impact resistance, by using a medium stirring mill for mixing when preparing the slurry, the powder component surface is made uniform with oily components. (See Patent Document 2).
Further, in the wet production method, by setting the compounding amount of the powder, the oil component and the water in the slurry within a specific range, the oil component can be uniformly and efficiently adhered to the surface of the powder, and the usability and A method for obtaining a powdered solid cosmetic having both impact resistance is disclosed (see Patent Document 3).

JP 2007-055990 A JP 2001-213722 A JP 2015-000855 A

As described in Patent Literatures 1 to 3, attempts are being made to achieve a balance between the usability when applied to the skin in a wet process and the usability such as the degree of puffing and drop strength.
On the other hand, in the case of the wet process, in order to improve the dispersibility in the preparation of the slurry and to sufficiently perform the surface treatment of the powder, a mechanical shearing mill such as a medium stirring mill as described in Patent Document 2 is used. A method of mixing using force is adopted.

However, when preparing a slurry using mechanical shearing force, a strong impact force is applied to the powder, so that the powder is excessively pulverized and the particle size becomes too small, and the powder is damaged. The present inventor has conceived that there is a problem that the inherent properties of the powder are impaired due to a reduction in glitter and the effects expected as a powder cosmetic are not sufficiently exhibited. As a solution to such a problem, a method of using a specific high-pressure fluid mixer in slurry preparation has been found (Japanese Patent Application No. 2017-137634).

  On the other hand, even if the slurry is uniformly dispersed in the preparation of the slurry, since the powder is re-agglomerated in the drying step, the particle size of the dried powder does not become fine, and there are problems such as insufficient touch. It has been found that by drying the mist thus obtained to obtain dry particles, dry particles having a fine particle diameter can be obtained (Japanese Patent Application No. 2016-135175).

  By applying each of the above techniques, the feeling of use and usability of the obtained powder cosmetic are improved, but the present invention provides a technique for further improving the feel and usability of the powder cosmetic.

  The present inventors use a specific high-pressure fluid mixer in the preparation of the slurry in the step of producing the powder cosmetic, and further, in the drying step, dry the sprayed mist to obtain dry particles, thereby giving a feeling of use and The inventors have conceived that the usability can be further improved, and have completed the present invention.

The present invention
A slurry preparation step of preparing a slurry by mixing at least a powder and an oily component in a solvent, and spraying a mist of the prepared slurry with a sprayer and drying the sprayed mist to obtain dry particles. A method for producing a powder cosmetic, comprising a drying step,
In the slurry preparation step, there is provided a method for producing a powder cosmetic using a high-pressure fluid mixer that mixes the powder and the oil component by flowing the solvent containing the powder and the oil component into the chamber as a high-pressure fluid. .

  The high-pressure fluid mixer preferably discharges a solvent containing a powder and an oily component as a high-pressure fluid, and mixes the powder and the oily component by obliquely colliding the high-pressure fluids. It is preferable that the fluid mixer mixes the powder and the oily component by generating cavitation in the chamber.

  The sprayer used in the spray drying step is provided with a four-fluid nozzle, and a form in which mist is sprayed from the tip of the nozzle is preferable.The powder is a spherical powder, and fine particles are arranged around plate-like particles. Preferably, the powder contains at least one powder selected from the group consisting of composite powders, and the powder preferably contains at least two powders having different particle diameters.

The powder, the following fine 5μm average particle diameter D _50, preferably form an average particle diameter D ₅₀ that includes at least the above extender pigment 20 [mu] m, also of the dry particles obtained in the spray-drying step, the volume average preferably form a ratio of _{D 90 (D 90 / D 50} ) of 2.0 or less with respect to particle size _{D 50,} also form said powder cosmetic is pressed powder or loose powder is preferred.

  ADVANTAGE OF THE INVENTION According to this invention, the uniformity of the particle size of the powder particle which comprises a powder cosmetics becomes extremely high, and the feeling of use and usability can provide the powder cosmetics which improved greatly.

It is a schematic diagram which shows one Embodiment of a high pressure fluid mixer. It is a schematic diagram which shows one Embodiment of a high pressure fluid mixer. It is a cross section showing the tip of the nozzle of the atomizer which can be used for the spray drying process in this embodiment.

  Hereinafter, a method for producing a powder cosmetic that is an embodiment of the present invention will be described, but the technical scope of the present invention is not limited to the following specific embodiments.

  The method for producing a powder cosmetic according to the present embodiment includes a slurry preparation step of preparing a slurry by mixing at least a powder and an oil component in a solvent, and spraying a mist of the prepared slurry with a sprayer, And a spray drying step of drying dried mist to obtain dry particles. Further, the method may further include a collecting step of collecting the dried particles obtained in the spray drying step, and further includes a molding step of filling and molding the dried particles obtained in the spray drying step in a mold. Is also good.

<Slurry preparation process>
The slurry preparation step is a step of preparing a slurry by mixing at least a powder and an oil component in a solvent. During the preparation of the slurry, components other than the powder and oily components required for the preparation of the cosmetic can be appropriately added.

In the present embodiment, in the slurry preparation step, a high-pressure fluid mixer that mixes the powder and the oil component by flowing a solvent containing the powder and the oil component in the high-pressure fluid chamber is used.
Conventionally, slurry preparation in the production of powder cosmetics has been performed by a method using mechanical shearing force such as a medium stirring mill in order to uniformly and sufficiently coat the powder surface with an oily component. However, it has been found that the powder powder is damaged or over-pulverized because a strong impact force is applied to the powder, which may cause a situation in which the effects expected as powder cosmetics are not sufficiently exhibited. . Therefore, the present inventors, as a mixer in which the powder in the slurry is not excessively pulverized and the powder in the slurry and the oily component are sufficiently mixed, the solvent containing the powder and the oily component is subjected to high pressure. It has been found to use a high-pressure fluid mixer flowing in a fluid chamber, ie a medialess mixer.

The high-pressure fluid mixer used in the present embodiment will be described with reference to FIGS.
FIG. 1 is a schematic diagram showing one embodiment of a high-pressure fluid mixer. The high-pressure fluid mixer shown in FIG. 1 is a mixer that discharges a solvent containing a powder and an oily component as a high-pressure fluid and mixes the high-pressure fluids by oblique collision.
The high-pressure injection type mixer 10 discharges a chamber 1 for mixing powder and oily components, supply ports 2a and 2b for supplying a solvent containing powder and oily components as high-pressure fluid into the chamber, and a mixed slurry. A slurry outlet 4 is provided.
The supply ports 2a and 2b are provided at substantially the same height on opposing side surfaces of the chamber 1. The flow path extending from the supply ports 2a and 2b to the opposite side to the center of the chamber is inclined, and the direction of discharging the slurry from the supply ports is higher than horizontal.

The solvent containing the powder and the oil component is pressurized by a pressurizer (not shown) and sent as a high-pressure fluid to a flow path connected to the supply ports 2a and 2b. The high-pressure fluid is sufficiently accelerated when supplied from the supply port into the chamber, and the high-pressure fluid discharged from the opposed supply ports 2a and 2b is obliquely collided at the collision point 3 substantially in the center of the chamber 1. I do. In addition, when the flow path extending from the supply ports 2a and 2b to the side opposite to the center of the chamber is not inclined, and is substantially horizontal, no oblique collision occurs. Since the high-pressure fluid collides at a high speed, the effect of stirring and mixing by the collision can be sufficiently expected.
In FIG. 1, there are two supply ports 2a and 2b, but if each supply port is provided at substantially the same height, there are four supply ports even if there are three supply ports. Alternatively, more supply ports may be provided depending on the shape of the chamber.

  The powder and oily component that collided at the collision point 3 in the chamber 1 are discharged from the slurry discharge port 4. In the collision between powders present in the solvent, the impact force on the powder is smaller than when the powder is directly subjected to mechanical shearing force from the medium, and by colliding the high-pressure fluid at high speed, The droplets of the oily component in the slurry become flat, and it becomes possible to cover many powders. In addition, according to the oblique collision, the impact force on the powder is smaller than in the head-on collision.

FIG. 2 is a schematic diagram illustrating an embodiment of the high-pressure fluid mixer. The high-pressure fluid mixer shown in FIG. 2 is a mixer that mixes powder and an oily component by generating cavitation in a chamber.
The high-pressure injection mixer 20 includes a chamber 11 for mixing the powder and the oily component, a supply port 12 for supplying a solvent containing the powder and the oily component into the chamber as a high-pressure fluid, and extending from the supply port into the chamber. An orifice 12a for generating cavitation 13 and a slurry outlet 14 for discharging the mixed slurry are provided.

The solvent containing the powder and the oil component is pressurized by a pressurizer (not shown) and sent to a flow path connected to the supply port 12 as a high-pressure fluid. The supply port 12 has an orifice 12a extending from the supply port into the chamber. Since the diameter of the orifice is designed to be very small, and the fluid pressurized to a high pressure inside the orifice is supplied at a high speed, cavitation 13 occurs. The powder and the oil component are mixed by the impact generated by the cavitation 13 bursting.
The fluid in which the powder and the oil component are mixed is discharged from the slurry discharge port 14 by the impact generated by the cavitation 13 bursting.
The method of mixing the powder and the oily component by generating cavitation in the solvent, the impact force on the powder is small compared to the mixing using media, and the high-pressure fluid is made to flow at high speed. In addition, the droplets of the oily component in the slurry become flat, and it becomes possible to cover many powders.

Examples of the high-pressure fluid mixer described above include NanoVita (manufactured by Yoshida Kikai Kogyo Co., Ltd.), nano3000 (manufactured by Miyu Co., Ltd.), and Starburst (manufactured by Sugino Machine Co., Ltd.).
The high pressure means, for example, that the pressure applied by an intensifier is higher than the atmospheric pressure, preferably 10 MPa or more, more preferably 30 MPa or more.

Hereinafter, powders, oily components, and the like to be contained in the slurry in the slurry preparation step will be described. 1) Powder The powder that can be used in this embodiment is a general term for organic or inorganic solids that do not dissolve in cosmetic raw materials such as water, oils and fats, surfactants, alcohols, and silicones.
Specific examples of the powder include kaolin, talc, mica, sericite, titanium mica, laminated resin particles (glitter), Ca / Al borosilicate, titanium sericite, titanium dioxide, iron oxide, zinc oxide, ultramarine, navy blue, Red No. 102, Red No. 226, Yellow No. 4 Aluminum lake, silica, alumina, calcium silicate, magnesium silicate, calcium carbonate, magnesium carbonate, methylsiloxane network polymer, cross-linked methylpolysiloxane resin, alkyl acrylate resin, nylon , Silk, cellulose or a composite material thereof.
The shape of the powder may be spherical, amorphous, porous, hollow, fibrous, plate-like or massive. Further, the surface may be subjected to a generally known surface treatment such as a silicone coating treatment, a metal soap coating treatment, and an acyl amino acid salt coating treatment.

The powder may be used alone in the slurry, or may be used in combination of two or more.
In the present embodiment, the content of the powder in the powder cosmetic is usually 65% by mass or more, may be 70% by mass or more, may be 75% by mass or more, and may be 80% by mass or more. . Further, it is usually 98% by mass or less, may be 95% by mass or less, and may be 90% by mass or less.

In the slurry preparation in the present embodiment, since the impact force received by the powder is small as compared with a mixer using a medium such as a medium stirring mill, it is effective when the extender pigment or the like contains a powder having a large particle diameter. is there. When the average particle diameter (D ₅₀ ) contains a powder having a particle diameter of 20 μm or more, when the average particle diameter (D ₅₀ ) contains a powder having a particle diameter of 25 μm or more, a powder having an average particle diameter (D ₅₀ ) of 30 μm or more When it contains, it is preferably applied.
Further, since the impact force applied to the powder is small, the damage to the powder is small, which is effective when the powder contains a fragile or easily damaged powder. It is preferably applied to a case containing a glitter powder, a case of containing a flaky powder, and the like.
It is also effective when two or more kinds of powders having different particle diameters, such as the above-mentioned powder having a large particle diameter and fine powder, are contained.
Examples of the fine-particle powder include fine-particle titanium oxide and fine-particle zinc oxide. Here, those having an average particle diameter (D ₅₀ ) of 10 μm or less are referred to as fine particles, and may be 5 μm or less, or 1 μm or less, It may be 500 nm or less, or 100 nm or less.

  The viscosity of the prepared slurry is not particularly limited, but is usually 100 mPa · s or more, preferably 1000 mPa · s or more, and usually 6000 mPa · s or less, and preferably 5000 mPa · s or less.

  In the present embodiment, a fine dry powder can be obtained by a spray drying process as described later. Therefore, it can be particularly preferably applied to the case where fine particle powder is contained, and the scattering effect of the fine particle powder can be sufficiently exhibited, and the SPF value is improved. In addition, it can be preferably applied to a case where a spherical powder is contained, a case where a composite powder in which fine particles are arranged around a plate-like powder is contained, and the like.

Examples of the spherical powder include organic spherical resin powders such as nylon, styrene, methyl methacrylate, polymethylsilsesquioxane powder, and organopolysiloxane elastomer powder, and inorganic powders such as silica, alumina, titanium oxide, magnesium carbonate, and calcium silicate. Spherical powders and the like are exemplified. These spherical powders are preferably 3% by mass or more, more preferably 5% by mass or more, also preferably 20% by mass or less, more preferably 15% by mass or less based on the total amount of the powder. By blending, it is possible to maintain the drop strength while improving the usability such as elongation and spread, and to improve the caking property.
The average particle diameter of the spherical powder is usually 1 μm or more, preferably 3 μm or more, and usually 50 μm or less, preferably 30 μm or less from the viewpoint of usability such as elongation and spread. The spherical powder may be subjected to a surface treatment by a known method for the purpose of improving dispersibility, adhesion and the like. The surface treatment may be a hydrophobic treatment or a hydrophilic treatment depending on the purpose.

  SMT-57S (manufactured by Teica Co., Ltd.) is exemplified as a composite powder in which fine particles are arranged around a plate-like powder, and these composite powders are preferably 4% by mass or more based on the total amount of the powder. By blending more preferably 6% by mass or more, more preferably 30% by mass or less, and more preferably 25% by mass or less, the drop strength is improved and the SPF value can be improved without causing caking properties.

Examples of the fine particle powder include fine particle titanium oxide and fine particle zinc oxide. Here, those having an average particle diameter of 10 μm or less are referred to as fine particles, and may be 1 μm or less, 500 nm or less, or 100 nm or less. May be. The fine particle powder is preferably 0% based on the total amount of the powder.
. By blending 5% by mass or more, more preferably 5% by mass or more, and preferably 20% by mass or less, and more preferably 15% by mass or less, the drop strength is improved, the caking property is improved, and the SPF value is improved. The transparency is not impaired when applied to the skin.

  As described above, according to the present embodiment, even in the case of the fine particle powder, the powder surface is uniformly coated with the oil component and aggregation can be prevented, so that the function of the powder can be maximized. It becomes possible.

2) Oily component Specific examples of the oily component that can be used in the present embodiment include macadamia nut oil, avocado oil, corn oil, olive oil, rapeseed oil, sesame oil, castor oil, safflower oil, cottonseed oil, jojoba oil, coconut oil, Animal and vegetable oils such as palm oil and liquid lanolin; hydrocarbon oils such as liquid paraffin, squalane and pristane; liquid fatty acids such as oleic acid and isostearic acid; liquid higher alcohols such as isostearyl alcohol and octyl dodecanol; cetyl isooctanoate and myristine Isopropyl acid, hexyldecyl isostearate, diisopropyl adipate, di-2-ethylhexyl sebacate, cetyl lactate, diisostearyl malate, ethylene glycol di-2-ethylhexanoate, neopentyl glycol dicaprate, di-2-heptyl Glycerin undecanoate, glyceryl tri-2-ethylhexanoate, cetyl ethylhexanoate, trimethylolpropane tri-2-ethylhexanoate, trimethylolpropane triisostearate, pentaneerythrit tetra-2-ethylhexanoate, glyceryl triisoate Synthetic ester oils such as stearate and glyceryl triisooctanoate; chain polysiloxanes such as dimethylpolysiloxane, methylphenylpolysiloxane and diphenylpolysiloxane; octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexanesiloxane and the like Cyclic polysiloxanes such as amino-modified polysiloxane, polyether-modified polysiloxane, alkyl-modified polysiloxane, and fluorine-modified polysiloxane Silicone oils such as Rokisan; and the like. However, those belonging to a specific surfactant group described later are not treated as oily components.

The oil component may be used alone or in combination of two or more.
When the oil component is blended in this embodiment, it is usually at least 5% by mass, preferably at least 10% by mass in the cosmetic. Further, it is usually at most 25 mass%, preferably at most 20 mass%.

3) Solvent The solvent may be any solvent that is generally used for preparing a slurry. Examples include purified water, volatile silicone oils, lower alcohols, ethers, volatile hydrocarbon oils, pyrrolidones, and the like. Further, these may be used as a mixture.
Among these solvents, it is preferable to contain ethyl alcohol and / or hydrogenated polyisobutene having a boiling point of 160 to 280 ° C.
Further, an emulsion in which the above oil component is dispersed in water can be used as a solvent.
The amount of the solvent may be an amount sufficient to mix the powder and the oil component, and is usually used in an amount of 50 parts by mass or more and 200 parts by mass or less based on 100 parts by mass of the powder.

4) Others The powder cosmetics manufactured in the present embodiment can widely mix components commonly used in powder cosmetics.

For example, examples of the active ingredient include a whitening ingredient, an anti-inflammatory ingredient, a plant extract and the like.
Examples of the surfactant include anionic surfactants such as fatty acid soaps (sodium laurate, sodium palmitate, etc.), potassium lauryl sulfate, triethanolamine ether alkyl sulfate, stearyltrimethylammonium chloride, benzalkonium chloride, lauryl Cationic surfactants such as amine oxides,
Betaine surfactants (alkyl betaine, amidobetaine, sulfobetaine, etc.), imidazoline amphoteric surfactants (2-cocoyl-2-imidazolinium hydroxide-1-carboxyethyloxy disodium salt, etc.), acylmethyltaurine Amphoteric surfactants such as
Sorbitan fatty acid esters (sorbitan monostearate, sorbitan sesquioleate, etc.), glycerin fatty acids (glycerin monostearate, etc.), propylene glycol fatty acid esters (propylene glycol monostearate, etc.), hydrogenated castor oil derivatives, glycerin alkyl ether POE sorbitan fatty acid esters (POE sorbitan monooleate, polyoxyethylene sorbitan monostearate, etc.), POE sorbite fatty acid esters (POE-sorbitol monolaurate, etc.), POE glycerin fatty acid esters (POE-glycerin monoisostearate) Rate), POE fatty acid esters (polyethylene glycol monooleate, POE distearate, etc.), POE alkyl ethers (POE2-octylde Sile ethers), POE alkyl phenyl ethers (POE nonyl phenyl ether, etc.), pluronics, POE / POP alkyl ethers (POE / POP2-decyl tetradecyl ether, etc.), tetronics, POE castor oil / hardened castor Non-ionic surfactants such as oil derivatives (POE castor oil, POE hardened castor oil, etc.), sucrose fatty acid esters, alkyl glucosides, and the like.

  Polyhydric alcohols include polyethylene glycol, glycerin, 1,3-butylene glycol, erythritol, sorbitol, xylitol, maltitol, propylene glycol, dipropylene glycol, diglycerin, isoprene glycol, 1,2-pentanediol, 2,4 -Hexylene glycol, 1,2-hexanediol, 1,2-octanediol and the like.

  Examples of the thickener include guar gum, quince seed, carrageenan, galactan, gum arabic, pectin, mannan, starch, xanthan gum, curdlan, methylcellulose, hydroxyethylcellulose, carboxymethylcellulose, methylhydroxypropylcellulose, chondroitin sulfate, dermatan sulfate, glycogen, Heparan sulfate, hyaluronic acid, sodium hyaluronate, tragacanth gum, keratan sulfate, chondroitin, mucoitin sulfate, hydroxyethyl guar gum, carboxymethyl guar gum, dextran, kerato sulfate, locust bean gum, succinoglucan, caronic acid, chitin, chitosan, carboxymethyl Chitin, agar, polyvinyl alcohol, polyvinylpyrrolidone, carboxyvinyl polymer, al Le-modified carboxyvinyl polymers, sodium polyacrylate, polyethylene glycol, and bentonite.

Examples of the ultraviolet absorber include a paraaminobenzoic acid ultraviolet absorber, an anthranilic acid ultraviolet absorber, a salicylic acid ultraviolet absorber, a cinnamic acid ultraviolet absorber, a benzophenone ultraviolet absorber, a sugar ultraviolet absorber, and 2- (2 UV absorbers such as'-hydroxy-5'-t-octylphenyl) benzotriazole and 4-methoxy-4'-t-butyldibenzoylmethane.

  The method of forming the slurry in the slurry preparation is not particularly limited as long as the above-mentioned fluid mixer is used, and a known method can be used. For example, a slurry can be formed by introducing a solvent to which a powder, an oily component, and other components are added as necessary, into the above-described mixer, and flowing the same as a high-pressure fluid in the chamber.

<Spray drying process>
The spray drying step is a step of spraying the mist of the prepared slurry with a sprayer and drying the sprayed mist to obtain dry particles.
The nebulizer is not limited as long as it can atomize and spray the slurry, and an existing nebulizer can be applied. In the present embodiment, a sprayer having a nozzle and spraying the mist from the nozzle tip is preferable because the mist can be easily dried in the subsequent drying step and the mist can be easily collected. Further, a sprayer having a four-fluid nozzle having a structure in which fluids ejected from two gas paths and two liquid paths collide at one point is more preferable.
An example of a nozzle capable of forming a mist and spraying the slurry will be described with reference to FIG. The shape of the nozzle is not limited to that shown in FIG. 3 as long as the mist can be sprayed.

  The nozzle 100 shown in FIG. 3 has a cylindrical nozzle edge 101 having one end having a sharp shape, and a slit which is disposed around the cylindrical nozzle edge 101 and forms a slurry flow channel 110 between the nozzle edge 101 and the nozzle edge 101. It comprises a first ring member 102 to be formed, and a second ring member 103 arranged around the first ring and forming a slit serving as a gas flow path 120 between the first ring member 102 and the first ring.

One end (the upper end in the figure) of the nozzle edge 101 has a sharp shape, and one end (the upper end in the figure) of the first ring member has a tapered shape so as to form the same plane as the inclination of the sharp shape.
The slurry flow channel 110 has a ring shape, and the slurry is injected from the slurry injection port 111 in a ring shape. On the other hand, the gas flow path 120 also has a ring shape, and the air flow is emitted from the air flow outlet 121 in a ring shape. Here, one end of the first ring member is tapered so as to form the same plane as the sharp inclination of the nozzle edge 101. Therefore, the airflow injected at a high speed from the airflow injection port 121 causes the slurry injected from the slurry injection port 111 to flow toward the tip of the nozzle edge at a high speed and impinges at the collision point 130, thereby causing the slurry to form a fine mist. Can be sprayed as

  In the present embodiment, as shown in FIG. 3, the slurry is turned into fine mist by using a nozzle having a mechanism for causing the slurry to flow by an air current from different directions and causing the slurry to collide at a collision point to generate mist. It is possible and preferable. The configuration for generating the airflow from different directions as described above is not limited to the configuration using the ring members, and may be any configuration that can form a plurality of flow paths from different directions. The cross-sectional view of FIG. 3 shows a four-fluid nozzle in which two airflow channels and two liquid flow channels are present. However, the present invention is not limited to this. For example, in the case of a cross section, a configuration in which three air flow channels and four air flow channels exist may be used, and three liquid flow channels and four liquid flow channels exist. It may be a configuration or a combination of these as appropriate.

  At this time, the injection flow rate of the slurry, the injection flow rate of the air stream, the flow rate of the air stream, and the like can be appropriately set according to the viscosity of the slurry, the desired particle size of the mist, and the like. The smaller the particle size of the mist, the smaller the particle size of the powder when dried, so the average particle size of the mist is preferably 30 μm or less, more preferably 20 μm or less, and more preferably 10 μm or less. More preferably, Even if a fine mist is generated, if the slurry contains a powder having a larger particle size, the powder does not become a fine mist, and particles near the particle size of the powder are sprayed. You. The average particle size of the mist containing submicron-order fine particles, for example, fine particle titanium oxide or fine particle zinc oxide, is preferably 20 μm or less, more preferably 10 μm or less, and even more preferably 5 μm or less. The average particle diameter of the mist can be calculated by enlarging an image taken by a high-speed camera or the like and measuring the average particle diameter of the major axis of 20 or more mist (droplets) on the screen. .

  The mist of the sprayed slurry is dried to be dried particles and collected. In general, high-temperature drying gas is used for drying, and the drying gas at a temperature at which the solvent used evaporates is sprayed on the slurry mist, so that the slurry becomes dry particles. Although the dried particles are appropriately collected, it is preferable to use a device that can be collected integrally with the sprayer and the dryer.

  In this embodiment, since the slurry is converted into a mist and dried particles are obtained by drying the mist, the particle diameter of the dried particles can be finely controlled. In particular, when fine particle powder is included, the oily component can be coated on each of the fine particle powder, so that the feeling in use is dramatically improved. In addition, when molded and solidified, the drop strength is significantly improved. Further, since the function of the powder can be maximized, for example, in the case of a cosmetic containing fine titanium oxide, fine zinc oxide, etc., an unpredictable effect such as an improvement in the SPF value is exhibited. Things.

Specifically, it is preferable that spray drying median diameter D ₅₀ of the resulting dry particles by is 20μm or less, more preferably at most 17 .mu.m, more preferably less 13 .mu.m, there at 10μm or less You may. Incidentally, the median diameter D ₅₀ can be measured by a laser diffraction particle size distribution measuring apparatus.
Further, in the cosmetic containing fine particle titanium oxide and / or fine particle zinc oxide, the particle size distribution of the dried particles obtained by the spray drying step preferably has a maximum value of 20 μm or less, and has a maximum value of 17 μm or less. More preferably, it has a maximum value of 13 μm or less, even more preferably 10 μm or less, and the maximum value is preferably derived from fine particles such as fine titanium oxide particles and fine zinc oxide particles.
In the case of a molded powder cosmetic, the cosmetic is rubbed with a puff, the rubbed cosmetic is classified with a 250-micron mesh, and the particle size of the cosmetic after the classification is measured. The particle size of the dried powder obtained by the spray drying step can be measured. The present inventors have confirmed that the particle size of the molded powder cosmetic measured by the above method and the particle size of the dried powder in the drying and spraying step substantially match.

In the case of an unmolded powder cosmetic such as loose powder, the particle diameter of the dry particles obtained by the spray drying step can be obtained by measuring the particle diameter as it is.
That is, another embodiment of the present invention is a loose powder containing at least a fine particle having an average particle diameter of 10 μm or less, and a loose powder containing an oily component, and having a median diameter D ₅₀ of 20 μm or less. is there.
Also, a pressed powder containing at least a fine particle having an average particle diameter of 10 μm or less, and a pressed powder containing an oily component, of the pressed powder rubbed by a puff, a pressed powder having a median diameter D of 250 μm mesh pass. Pressed powder wherein ₅₀ is 20 μm or less.

In the present embodiment, the slurry is prepared using a high-pressure fluid mixer, the mist of the prepared slurry is sprayed by a sprayer, and the sprayed mist is dried to obtain dry particles, thereby giving a feeling of use and usability. Can greatly improve the powder cosmetic.
Specifically, through the present embodiment, the uniformity of the particle size of the powder particles constituting the powder cosmetic is extremely high. The dried particles obtained in the spray drying step preferably have a ratio (D ₉₀ / D ₅₀ ) of the value D ₉₀ of the cumulative distribution 90% from the small particle size side to the median particle size D ₅₀ (D ₉₀ / D ₅₀ ) of 2.0 or less, More preferably, it is 1.9 or less.

<Molding process>
In the present embodiment, the molding step provided as desired is a step of filling the mold with the dry powder obtained in the spray drying step and molding. It may be pressed powder by molding, or loose powder without molding. In the case of using a pressed powder, the feeling of use is preferable, and the drop strength is improved. When loose powder is used, the feeling of use is preferable.

  Hereinafter, the present invention will be described in more detail by experiments.

<Experimental example 1>
A total of 100 parts by mass of the powder and the oil agent shown in Table 1 was added to 60 parts by mass of a solvent (hydrogenated polyisobutene), and stirred using a double planet mixer (DPM) to prepare a slurry.
Next, the obtained slurry was sprayed with a mist at a flow rate of 4 g / min of an air stream for spraying the slurry by a sprayer equipped with a nozzle having the structure shown in FIG. 3 and dried to obtain dried particles. The median diameter D ₅₀ of the obtained dried particles is 17.58 μm, the value D _{90 of the} 90% cumulative distribution from the small particle size side is 36.22 μm, and (D ₉₀ / D ₅₀ ) is 2 0.06.
The obtained dried particles were molded by a press to obtain a powdered solid cosmetic 1.

<Experimental example 2>
100 parts by mass of the mixture of the powder and the oil agent shown in Table 1 was added to 60 parts by mass of the solvent (hydrogenated polyisobutene). The solvent containing the powder and the oil agent was introduced into a high-pressure fluid mixer Starburst (manufactured by Sugino Machine Co., Ltd.) schematically shown in FIG. 2 to prepare a slurry. In preparing the slurry, the pressure of the fluid in the mixer was increased to about 70 MPa by a pressure intensifier.
The prepared slurry was filled in a resin middle plate and dried to obtain a powdered solid cosmetic 2.

<Experimental example 3>
100 parts by mass of the mixture of the powder and the oil agent shown in Table 1 was added to 60 parts by mass of the solvent (hydrogenated polyisobutene). The solvent containing the powder and the oil agent was introduced into a high-pressure fluid mixer Starburst (manufactured by Sugino Machine Co., Ltd.) schematically shown in FIG. 2 to prepare a slurry. In preparing the slurry, the pressure of the fluid in the mixer was increased to about 70 MPa by a pressure intensifier.
Next, the obtained slurry was sprayed with a mist at a flow rate of 4 g / min of an air stream for spraying the slurry by a sprayer equipped with a nozzle having the structure shown in FIG. 3 and dried to obtain dried particles. The median diameter D ₅₀ of the obtained dried particles is 10.81 μm, the value D _{90 of the} 90% cumulative distribution from the small particle size side is 19.19 μm, and (D ₉₀ / D ₅₀ ) is 1 Was .78.
The obtained dry particles were molded by a press machine to obtain a powdered solid cosmetic 3.

<Evaluation>
The obtained powdered solid cosmetics 1 to 3 were evaluated according to the following items and evaluation criteria.
-Uniformity of elongation and spread: Ten evaluators used and evaluated the powdered solid cosmetics. Table 2 shows the results.
◎: 9 or more of 10 persons answered that the spread was uniform. ○: 6 to 8 of 10 persons answered that the spread was uniform. ３: 3 to 5 of 10 persons were uniform. Answer: x: 0 to 2 out of 10 responded that the spread was uniform

-Softness of touch: Ten evaluators used and evaluated the powdered solid cosmetics.
◎: 9 or more of 10 respondents answered that the touch was soft. ：: 6 to 8 of 10 respondents felt that the touch was soft. △: 3 to 5 of 10 respondents felt that the touch was soft. X: 0 of 10 respondents. ~ 2 people feel soft

-No powdery finish: Ten evaluators used the powdered solid cosmetic and evaluated.
◎: 9 or more out of 10 respondents have no finished powdery ○: 6 to 8 out of 10 respondents have no finished powdery △: 3 to 5 out of 10 finished X: 0 to 2 out of 10 respondents have no finished powder

-Drop strength: The state after each powder solid cosmetic was dropped five times from a height of 50 cm onto a plywood having a thickness of 50 mm was evaluated based on the following evaluation criteria.
◎: No cracks or chips at all ○: Very slight cracks or chips on the surface △: Partially cracks or chips X: There are cracks or chips entirely

-Difficulty of caking: NBR (nitrile rubber) material, 52 x 44 x 8.5 mm size cosmetic puff rubbing the surface of each powder solid cosmetic with a load of 2.9 N according to the following evaluation criteria It was evaluated based on:
◎: Caking does not occur on the way and is easy to remove ○: Caking does not occur on the way, but it is difficult to remove △: Caking occurs on the way but can be used up to the end ×: Caking occurs on the way and uses up to the end Can not

10, 20 High-pressure fluid mixer 1, 11 Chamber 2a, 2b Raw material supply port 12 Raw material supply port 12a Orifice 3 Collision point 13 Cavitation 4, 14 Discharge port 100 Nozzle 101 Nozzle edge 102 First ring member 103 Second ring member 110 Slurry Flow path 111 Slurry injection port 120 Gas flow path 121 Gas injection port 130 Collision point

Claims (8)

A slurry preparation step of preparing a slurry by mixing at least a powder and an oily component in a solvent, and spraying a mist of the prepared slurry with a sprayer and drying the sprayed mist to obtain dry particles. A method for producing a powder cosmetic, comprising a drying step,
In the slurry preparation step, using a high-pressure fluid mixer that mixes the powder and the oil component by flowing the solvent containing the powder and the oil component in the chamber as a high-pressure fluid of 30 MPa to 70 MPa ,
The spray-drying atomizers for use in the process comprises a four-fluid nozzle, sprayed mist from the tip of the nozzle, the manufacturing method of powder cosmetics.   2. The powder according to claim 1, wherein the high-pressure fluid mixer discharges a solvent containing the powder and the oil component as a high-pressure fluid, and mixes the powder and the oil component by obliquely colliding the high-pressure fluids with each other. 3. Manufacturing method of body cosmetics.   The method for producing a powder cosmetic according to claim 1, wherein the high-pressure fluid mixer mixes the powder and the oily component by an impact generated by rupture of cavitation generated in the chamber. The powder according to any one of claims 1 to 3 , wherein the powder includes at least one powder selected from the group consisting of a spherical powder and a composite powder in which fine particles are arranged around plate-like particles. The method for producing a powder cosmetic according to the above item. The method for producing a powder cosmetic according to any one of claims 1 to 4 , wherein the powder includes at least two powders having different particle sizes. The powder had an average particle diameter D ₅₀ of less 5μm fine, having an average particle diameter D ₅₀ of at least the above extender pigment 20 [mu] m, the powder cosmetic according to any one of claims 1 to 5 Production method. Wherein the dry particles obtained in the spray drying process, the ratio of _{D 90} to the volume-average particle diameter _{D 50 (D 90 / D 50} ) is 2.0 or less, according to any one of claims 1 to 6 Manufacturing method of powder cosmetics. The method for producing a powder cosmetic according to any one of claims 1 to 7 , wherein the powder cosmetic is a pressed powder or a loose powder.

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