JP2023042018A - Milky lotion-like skin cosmetic - Google Patents

Abstract

To provide a milky lotion-like skin cosmetic having no sticky feeling, no friction feeling and good sense of use.SOLUTION: There is provided a milky lotion-like skin cosmetic containing 0.01 to 0.1 mass% of a silica aerogel. The silica aerogel preferably has an average circularity of 0.8 or more. The silica aerogel preferably has an M value representing methanol wettability of 20 or more. The silica aerogel preferably has a volume-based cumulative 50% diameter (D50) of 1 μm or more and 200 μm pr less as measured by the Coulter counter method. The silica aerogel preferably has an oil absorption of 400 mL/100 g or more and 800 mL/100 g or less.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to emulsion skin cosmetics.

Emulsion-like cosmetics, so-called emulsions, are one of skin care cosmetics intended to protect the skin from dryness, ultraviolet rays, oxidation, stress, etc., maintain the homeostasis inherent to the skin, and keep it healthy. The milky lotion contains a large amount of water and an appropriate amount of oil, and is therefore effective in maintaining the skin's moisture balance and moisturizing and softening the skin.
Ingredients commonly used in milky lotions include oily ingredients, aqueous ingredients, surfactants, thickeners, and the like, and there are many types and combinations of these ingredients. Since emulsions contain oil, when the aqueous component evaporates after application, the skin tends to feel sticky due to the oil. For example, by blending 1 to 50% by mass of hydrophobic powder in the inner oil phase and 0.1 to 3% by mass of hydrophobic powder selected from resin powder in the outer water phase, oil-in-water emulsified makeup that suppresses stickiness. have been developed (see, for example, Patent Document 1).

JP 2009-286748 A

However, when a large amount of hydrophobic powder is blended for the purpose of reducing stickiness, the emulsion as a whole tends to thicken and creak after application, leaving room for improvement.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an emulsion skin cosmetic that is free from stickiness and creaking.

The inventors of the present invention have made intensive studies to solve the above problems, and as a result, it is possible to obtain an emulsion skin cosmetic that is free from stickiness and creaking by blending a very small amount of silica airgel. The inventors have found that and completed the present invention.
That is, the emulsion cosmetic of the present invention contains 0.01 to 0.1% by mass of silica airgel.
In addition, in the milky lotion cosmetic of the present invention, the silica airgel preferably has an average circularity of 0.8 or more.
The milky lotion cosmetic of the present invention preferably has an M value of 20 or more, which represents the methanol wettability of the silica airgel.
Further, in the milky lotion cosmetic of the present invention, the volume-based cumulative 50% diameter (D50) measured by the Coulter counter method of the silica airgel is preferably 1 μm or more and 200 μm or less.
In the milky lotion cosmetic of the present invention, the silica airgel preferably has an oil absorption of 400 mL/100 g or more and 800 mL/100 g or less.

The milky lotion cosmetic of the present invention is a milky lotion cosmetic without a sticky feeling and without a creaking feeling.

The milky lotion cosmetic of the present invention will be described in detail below based on embodiments.

[Emulsion cosmetics]
The emulsion cosmetic of the present invention contains 0.01 to 0.1% by mass of silica airgel. Furthermore, the emulsion cosmetic of the present invention contains 55 to 95% by mass of an aqueous component, 1 to 30% by mass of an oily component, 1 to 3% by mass of a surfactant, 1 to 10% by mass of a moisturizer, and other components. may contain ingredients. Each component will be described in detail below.

<Silica airgel>
The silica airgel used in the emulsion cosmetic of the present invention can be prepared by a known method. For example, it can be prepared by the methods described in International Publication No. 2012/057086, JP-A-2014-218433, and the like.
Here, silica airgel means a solid material having a porous silica skeleton structure and accompanied by a gas as a dispersion medium, particularly a solid material with a porosity of 60% or more. Silica airgel exhibits excellent mechanical strength despite its high porosity. The porosity is a value expressed by volume percentage of the amount of gas contained in the apparent volume.

(Content)
The lower limit of the content of silica airgel contained in the emulsion cosmetic according to the present embodiment is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, relative to the total mass of the emulsion cosmetic. preferable. Moreover, the upper limit of the content of silica airgel is preferably 0.10% by mass or less, more preferably 0.08% by mass or less, relative to the total mass of the milky lotion cosmetic. If the content of silica airgel is less than the above lower limit, the effect of absorbing the oily components and sebum in the formulation cannot be obtained, resulting in stickiness and poor feel. On the other hand, when the content of silica airgel exceeds the above upper limit, creaking is felt after application, and the feel is deteriorated. When the content of the silica airgel is within the above range, it is possible to provide a non-sticky and non-squeaky emulsion cosmetic.

(Porosity)
The porosity of silica airgel is preferably 60% or more, more preferably 80% or more, and even more preferably 90% or more. The upper limit of the porosity of silica airgel is preferably 99% or less, more preferably 98% or less. If the porosity is less than the above lower limit, the effect of absorbing oily components and sebum in the formulation cannot be obtained, resulting in a sticky feel and a poor feel. When the porosity is within the above range, it is possible to provide a milky lotion cosmetic that is free from stickiness and creaking. In addition, it is difficult to obtain a silica airgel with a porosity exceeding the above upper limit, and even if it is obtained, when the emulsion cosmetic is applied, it tends to feel sticky and the feel is worse.
The porosity is a value that expresses the amount of gas contained in the apparent volume in terms of volume percentage.

(average circularity)
The lower limit of the average circularity of silica airgel is preferably 0.8 or more, more preferably 0.85 or more, and even more preferably 0.90 or more. If the average circularity is less than the above lower limit, irregularly shaped particles and agglomerated particles are increased, resulting in deterioration of flowability, filling property and rolling property, and deterioration of tactile sensation. In addition, when the average circularity is within the above range, it is possible to provide a milky lotion cosmetic having good fluidity, filling properties, and rolling properties, and having excellent tactile sensation.
The average circularity is a value calculated by an image analysis method using a scanning electron microscope (SEM). Specifically, the average circularity is an arithmetic mean value of circularities obtained by image analysis of SEM images of 2000 or more silica airgels observed at a magnification of 1000 times with an SEM. The circularity of silica airgel is a value determined by the following formula (1).
C=4πS/L ² (1)
Here, in formula (1), C represents the circularity, S represents the area (projected area) that the silica airgel occupies in the image, and L is the length of the outer peripheral portion of the silica airgel in the image (perimeter long).

(M value)
The lower limit of the M value, which represents the methanol wettability of silica airgel, is preferably 20 or more, more preferably 30 or more, and even more preferably 35 or more. The upper limit of the M value of silica airgel is preferably 60 or less, more preferably 55 or less, and even more preferably 50 or less. When the M value is less than the above lower limit, the effect of imparting sebum absorption and water repellency cannot be obtained, and the make-up lasts longer. In addition, it is difficult to obtain a silica airgel with an M value exceeding the above upper limit, and even if it is obtained, when the emulsion cosmetic is applied, it tends to feel sticky and the feel is worse. When the M value is within the above range, it is possible to provide a milky lotion cosmetic that has good compatibility with other raw materials, gives a smooth feel, is not sticky and does not creak. . In order to obtain a silica airgel having an M value within the above range, silylation treatment is performed using a silylating agent according to the methods described in WO 2012/057086, JP 2014-218433 , etc. good. Silica silylate is a hydrophobic silica airgel in which hydroxy groups on the surface of silica airgel are replaced with silyl groups by silylation treatment.
The M value is measured by adding 0.2 g of silica airgel to a 250 mL beaker containing 50 mL of water and stirring with a magnetic stirrer. Using a burette, methanol is added through a tube so as not to come into direct contact with the sample, and titration is performed with the point at which the entire amount of the sample is dispersed and suspended in the solution as the end point. M value is the volume percentage (vol%) of methanol in the methanol-water mixed solvent at the end point. The M value is a value obtained by the following formula (2).
M value = methanol drop amount (mL) / (methanol drop amount (mL) + 50 mL) x 100 (2)

(Volume-based cumulative 50% diameter)
The lower limit of the volume-based cumulative 50% diameter (D50) of silica airgel is preferably 1 µm or more, more preferably 2 µm or more, and even more preferably 5 µm or more. The upper limit of D50 of silica airgel is preferably 200 μm or less, more preferably 100 μm or less, and even more preferably 20 μm or less. It is difficult to obtain a silica airgel having a D50 of less than the above lower limit, and even if it is obtained, it tends to feel sticky when applied with an emulsion cosmetic, resulting in a poor feel. On the other hand, when the D50 exceeds the above upper limit, the silica airgel tends to separate from the milky lotion cosmetic, and in addition, the feel becomes rough and deteriorates. When the D50 is within the above range, it is possible to provide a milky lotion cosmetic that has a smooth feel without stickiness or creaking.
D50 of silica airgel is a value measured by the Coulter Counter method.

(oil absorption)
The lower limit of the oil absorption of silica airgel is preferably 400 mL/100 g or more, more preferably 500 mL/100 g or more, and even more preferably 550 mL/100 g or more. The upper limit of the oil absorption of silica airgel is preferably 800 mL/100 g or less, more preferably 750 mL/100 g or less, and even more preferably 700 mL/100 g or less.
If the oil absorption is less than the above lower limit, the effect of absorbing the oily components and sebum in the formulation cannot be obtained, resulting in stickiness and poor feel. In addition, it is difficult to obtain a silica airgel with an oil absorption exceeding the above upper limit, and even if it is obtained, it tends to creak and feel worse after application. When the oil absorption is within the above range, it is possible to provide a non-sticky and creaking emulsion cosmetic.
The oil absorption is a value measured by the method described in JIS K5101-13-1 “Refined linseed oil method”.

(Specific surface area)
The lower limit of the specific surface area of silica airgel is preferably 350 m ² /g or more, more preferably 400 m ² /g or more, and even more preferably 500 m ² /g or more. The upper limit of the specific surface area of silica airgel is preferably 1000 m ² /g or less, more preferably 900 m ² /g or less, and even more preferably 850 m ² /g or less. When the specific surface area is less than the above lower limit, the milky lotion cosmetic becomes sticky to the touch, and the feel to the touch deteriorates. In addition, it is difficult to obtain a silica airgel with a specific surface area exceeding the above upper limit, and even if it is obtained, when the emulsion cosmetic is applied, it tends to feel sticky and the feel is worse.
When the specific surface area is within the above range, it is possible to provide a milky lotion cosmetic that is free from stickiness and creaking.
A specific surface area is a value measured by the BET method. Specifically, the sample to be measured is dried at a temperature of 200° C. for 3 hours or more under a vacuum of 1 kPa or less, and then the adsorption isotherm of only the nitrogen adsorption side at liquid nitrogen temperature is measured. The value obtained by analyzing the adsorption isotherm by the BET method is the specific surface area. The pressure range used for the analysis at that time is a relative pressure range of 0.1 to 0.25.

(pore volume)
The lower limit of the pore volume of silica airgel is preferably 3 mL/g or more, more preferably 3.5 mL/g or more, and even more preferably 4.0 mL/g or more. Also, the upper limit of the pore volume of the airgel is preferably 6 mL/g or less, more preferably 5.5 mL/g or less, and even more preferably 5.0 mL/g or less. If the pore volume is less than the above lower limit, the effect of absorbing sebum cannot be obtained, and the emulsion-like cosmetic composition becomes sticky to the touch, and the touch to the touch is deteriorated. In addition, it is difficult to obtain a silica airgel with a pore volume exceeding the above upper limit, and even if it is obtained, when the emulsion-like cosmetic is applied, it tends to feel sticky and the feel is worse. When the pore volume is within the above range, it is possible to provide a non-sticky and non-squeaky emulsion cosmetic.
The pore volume is a value measured by the BJH method. Specifically, the sample to be measured is dried at a temperature of 200° C. for 3 hours or more under a vacuum of 1 kPa or less, and then the adsorption isotherm of only the nitrogen adsorption side at liquid nitrogen temperature is measured. Then, the adsorption isotherm is analyzed by the BJH method (Barrett, E. P.; Joyner, L. G.; Halenda, P. P., J. Am. Chem. Soc. 73, 373 (1951)). A pore volume derived from pores with a pore radius of 1 nm or more and 100 nm or less is obtained.

(pore radius)
The lower limit of the peak of the pore radius of silica airgel is preferably 10 nm or more, more preferably 12 nm or more, and even more preferably 13 nm or more. The upper limit of the peak of the pore radius of silica airgel is preferably 40 nm or less, more preferably 35 nm or less, and even more preferably 30 nm or less. Moreover, it is preferable that pores having a pore radius of 1 nm to 100 nm are present in an amount of 70% by volume or more of the total pore volume.
It is difficult to obtain a silica airgel with a pore radius peak less than the above lower limit. On the other hand, when the peak of the pore radius exceeds the above upper limit, the effect of sebum absorption cannot be obtained, and the emulsion-like cosmetic composition becomes sticky to the touch, which deteriorates the touch. When the peak pore radius is within the above range, it is possible to provide a non-sticky and non-squeaky emulsion cosmetic.
The pore radius is a value measured by the BJH method. Specifically, the sample to be measured is dried at a temperature of 200° C. for 3 hours or more under a vacuum of 1 kPa or less, and then the adsorption isotherm of only the adsorption side of nitrogen at liquid nitrogen temperature is measured. Then, a pore distribution curve (volume distribution curve) obtained by analyzing the adsorption isotherm by the BJH method and plotting the differential of the cumulative pore volume by the logarithm of the pore radius on the vertical axis and the pore radius on the horizontal axis. The pore radius with the maximum peak value is defined as the pore radius peak.

(C value)
The lower limit of the carbon content (C value) representing the hydrophobicity of silica airgel is preferably 7.5% by mass or more, more preferably 8.0% by mass or more, and 8.5% by mass or more. is more preferred. The upper limit of the C value of silica airgel is preferably 20% by mass or less, more preferably 15% by mass or less, and even more preferably 12% by mass or less. If the C value is less than the above lower limit, the effect of absorbing the oily components and sebum in the formulation cannot be obtained, resulting in stickiness and poor feel. In addition, it is difficult to obtain a silica airgel with a C value exceeding the above upper limit, and even if it is obtained, when the emulsion cosmetic is applied, it tends to feel sticky and the touch tends to deteriorate. When the C value is within the above range, it is possible to provide a non-sticky and non-squeaky emulsion cosmetic.
The C value can be measured by quantifying the amount of carbon dioxide generated when silica airgel is oxidized in air or oxygen at a temperature of about 1000 to 1500°C.

<Aqueous component>
As the aqueous component contained in the milky lotion cosmetic of the present invention, it is possible to contain components used in ordinary cosmetics. For example, ordinary water, such as tap water and well water, which conforms to water quality standards under the Waterworks Act, purified water obtained by distilling ordinary water or purifying ordinary water through an ion-exchange resin, deep sea water, and hot spring water Alkali ion water, which is generated at the cathode when water containing calcium is electrolyzed, or the like can be used.

(Content)
The lower limit of the content of the aqueous component contained in the emulsion cosmetic of the present invention is preferably 55% by mass or more, more preferably 60% by mass or more, relative to the total mass of the emulsion cosmetic. Moreover, the upper limit of the content of the aqueous component is preferably 95% by mass or less, more preferably 90% by mass or less, relative to the total mass of the milky lotion cosmetic. When the content of the aqueous component is less than the above lower limit, when the emulsion cosmetic is applied, it does not give a fresh feel, and the feel becomes sticky and deteriorates. Moreover, when the content of the aqueous component exceeds the above upper limit, it becomes difficult to obtain a moisturizing effect. When the content of the aqueous component is within the above range, it is possible to provide a non-sticky and non-squeaky emulsion cosmetic.

<Oil component>
As the oily component contained in the milky lotion cosmetic of the present invention, it is possible to contain components used in ordinary cosmetics. In addition, it may contain any one of liquid oil, semi-solid/solid oil, or a combination of two or more.
For example, liquid oils include hydrocarbons; squalane, liquid paraffin, α-olefin oligomers, acute paraffin, etc.; oils and fats; sunflower seed oil, olive oil, macadamia nut oil, castor oil, rosehip oil, almond oil, meadowfoam oil, etc. vegetable oil, tri (caprylic/capric acid) glyceryl, triethylhexanoin, esters; esters and the like, silicone oils; dimethicone, phenylmethicone, cyclopentasiloxane, and the like.
In addition, semi-solid and solid oils include fatty acids; myristic acid, palmitic acid, stearic acid, isostearic acid, oleic acid, behenic acid, etc.; higher alcohols; cetanol, stearyl alcohol, behenyl alcohol, cholesterol, lanolin alcohol, etc.; waxes/oils; cetyl palmitate, beeswax, lanolin, candelilla wax, carnauba wax, rice bran wax, shea butter, cacao butter, hydrogenated palm oil and the like.

(Content)
The lower limit of the content of the oily component contained in the emulsion cosmetic composition of the present invention is preferably 1% by mass or more, more preferably 2% by mass or more, relative to the total mass of the emulsion cosmetic composition. Moreover, the upper limit of the content of the oil component is preferably 30% by mass or less, more preferably 25% by mass or less, relative to the total mass of the milky lotion cosmetic. When the content of the oily component is less than the above lower limit, it becomes difficult to obtain a moisturizing effect when the emulsion cosmetic is applied. On the other hand, if the content of the oily component exceeds the above upper limit, the fresh feeling cannot be obtained, and the feeling becomes sticky and deteriorates. When the content of the oil component is within the above range, it is possible to provide a non-sticky and non-squeaky emulsion cosmetic.

<Surfactant>
As the surfactant contained in the milky lotion cosmetic of the present invention, it is possible to contain ingredients used in ordinary cosmetics. Examples include lipophilic nonionic surfactants, hydrophilic nonionic surfactants, and other surfactants.
The lipophilic nonionic surfactant is not particularly limited, and examples include sorbitan monooleate, sorbitan monoisostearate, sorbitan monolaurate, sorbitan monopalmitate, sorbitan monostearate, sorbitan sesquioleate, and sorbitan trioleate. Sorbitan fatty acid esters such as ate, diglycerol sorbitan penta-2-ethylhexylate, diglycerol sorbitan tetra-2-ethylhexylate, monocottonseed fatty acid glycerol, glyceryl monoerucate, glyceryl sesquioleate, glyceryl monostearate, α,α glycerol pyroglutamate '-oleate, glycerin polyglycerin fatty acids such as glyceryl monostearate malic acid, propylene glycol fatty acid esters such as propylene glycol monostearate, hardened castor oil derivatives, glycerin alkyl ethers and the like.

The hydrophilic nonionic surfactant is not particularly limited. POE sorbitol fatty acid esters such as laurate, POE sorbitol monooleate, POE sorbitol pentaoleate, POE sorbitol monostearate, POE such as POE glycerin monostearate, POE glycerin monoisostearate, POE glycerin triisostearate Glycerin fatty acid esters, POE monooleate, POE distearate, POE dioleate, POE fatty acid esters such as ethylene glycol distearate, POE lauryl ether, POE oleyl ether, POE stearyl ether, POE behenyl ether, POE 2-octyldodecyl ether, POE cholestanol POE alkyl ethers such as ether, POE alkyl phenyl ethers such as POE octylphenyl ether, POE nonylphenyl ether, POE dinonylphenyl ether, Pluronic type such as bruronic, POE POP cetyl ether, POE POP 2-decyl tetra Decyl ether, POE/POP monobutyl ether, POE/POP hydrogenated lanolin, POE/POP alkyl ethers such as POE/POP glycerin ether, tetra POE/tetra POP ethylenediamine condensates such as Tetronic, POE castor oil, POE hardening Castor oil, POE hydrogenated castor oil monoisostearate, POE hydrogenated castor oil triisostearate, POE hydrogenated castor oil monopyroglutamic monoisostearic acid diester, POE hydrogenated castor oil POE castor oil hydrogenated castor oil derivatives such as maleic acid, POE POE beeswax/lanolin derivatives such as sorbit beeswax, alkanolamides such as coconut oil fatty acid diethanolamide, lauric acid monoethanolamide, and fatty acid isopropanolamide, POE propylene glycol fatty acid esters, POE alkylamines, POE fatty acid amides, sucrose fatty acid esters, POE Nonylphenyl formaldehyde condensate, alkylethoxydimethylamine oxide, trioleyl phosphate, PEG fatty acid ester, and the like can be mentioned.

Examples of the other surfactants include anionic surfactants such as fatty acid soaps, higher alkyl sulfates, POE triethanolamine lauryl sulfate, alkyl ether sulfates, fatty acid salts, acyl methyl taurates, and acyl glutamates. , alkyltrimethylammonium salts, alkylpyridinium salts, alkylquaternary ammonium salts, alkyldimethylbenzylammonium salts, POE alkylamines, alkylamine salts, cationic surfactants such as polyamine fatty acid derivatives, and imidazoline amphoteric surfactants, betaine An amphoteric surfactant such as an amphoteric surfactant may be added to the extent that there is no problem with stability and skin irritation.

(Content)
The lower limit of the surfactant content in the emulsion cosmetic of the present invention is preferably 1% by mass or more, more preferably 2% by mass or more, relative to the total mass of the emulsion cosmetic. Moreover, the upper limit of the surfactant content is preferably 3% by mass or less, more preferably 2.8% by mass or less, relative to the total mass of the milky lotion cosmetic. When the content of the surfactant is less than the above lower limit, it becomes difficult to form and stably maintain an emulsified state. On the other hand, if the content of the surfactant exceeds the above upper limit, the touch becomes slippery or sticky, and the touch becomes worse. When the content of the surfactant is within the above range, it is possible to provide an emulsion cosmetic that has good storage stability and a good feel when applied.

<Moisturizer>
As a moisturizing agent contained in the milky lotion cosmetic of the present invention, it is possible to contain ingredients used in ordinary cosmetics. For example, glycerin, diglycerin, 1,3-butylene glycol, propylene glycol, dipropylene glycol, polyethylene glycol, sorbitol, maltitol, trehalose, POE methylglucoside, trimethylglycine, amino acids, sodium hyaluronate, other polysaccharides, A biopolymer etc. can be mentioned.

(Content)
The lower limit of the content of the moisturizing agent contained in the emulsion cosmetic of the present invention is preferably 1% by mass or more, more preferably 2% by mass or more, relative to the total mass of the emulsion cosmetic. Moreover, the upper limit of the content of the moisturizing agent is preferably 10% by mass or less, more preferably 8% by mass or less, relative to the total mass of the milky lotion cosmetic. When the content of the humectant is less than the above lower limit, it becomes difficult to obtain a moisturizing effect. On the other hand, if the content of the moisturizing agent exceeds the above upper limit, the touch becomes slippery or sticky, and the touch becomes worse. When the content of the humectant is within the above range, it is possible to provide an emulsion cosmetic that has a good moisturizing effect and a good feel when applied.

<Other ingredients>
The emulsion-like cosmetic of the present invention further contains, in addition to the above components, components used in ordinary cosmetics, such as thickeners, fragrances, pH adjusters, antioxidants, chelating agents, pigments, anti-inflammatory agents, Astringents, vitamins, whitening/anti-aging ingredients, UV absorbers, UV scattering agents, bactericides, preservatives, extender pigments, white pigments, coloring pigments, pearlescent pigments (pearl agents), lower alcohols, polyhydric alcohols, Blood circulation promoters, cooling agents, skin activators, dyes and the like can be contained.

[Method for producing emulsion cosmetic]
The emulsion cosmetic composition of the present invention can be produced by a known method. For example, the dispersed phase (oil phase) is added to the dispersion medium (water phase in the case of O/W emulsion) while stirring. , after preliminary emulsification, emulsified particles can be micronized by mechanical force.

EXAMPLES The embodiments of the present invention will be described in more detail below with reference to examples. Of course, the present invention is not limited to the following examples, and it goes without saying that various aspects are possible for the details. Furthermore, the present invention is not limited to the above-described embodiments, and can be modified in various ways within the scope of the claims. It is included in the technical scope of the invention. In addition, all documents described in this specification are incorporated by reference. In addition, the evaluation of Examples and Comparative Examples was carried out by the following methods.

[Measuring method]
(Measurement of average circularity)
Image analysis of SEM images observed at 1000 times magnification using SEM (Hitachi High-Technologies S-5500, acceleration voltage 3.0 kV, secondary electron detection) for 2000 or more silica airgels, and the average circular shape according to the above definition. degree was calculated.
(M value)
A 0.2 g sample of silica airgel was added to a 250 mL beaker containing 50 mL of water and stirred with a magnetic stirrer. After stirring, a burette was used to add methanol through a tube so as not to directly contact the sample, and titration was performed with the point where the entire amount of the sample was dispersed and suspended in the solution as the end point. The volume percentage (vol%) of methanol in the methanol-water mixed solvent at the end point was calculated from the above formula (2) and used as the M value.
(D50)
D50 was measured by a precision particle size distribution analyzer Multisizer 3 (manufactured by Beckman Coulter, Inc.) according to the Coulter counter method. 0.3 g of silica was added to 40 ml of ethanol, and dispersed for 5 minutes at an output of 100 W using an ultrasonic cleaner UT-105S manufactured by Sharp Manufacturing Corporation. The above dispersion was carried out by using a laboratory screw tube bottle with a capacity of 50 ml and placing it in a washing tank filled with an appropriate amount of water. The obtained ethanol dispersion was measured using a 100 μm aperture tube. From the obtained particle size distribution, D50 for volume distribution was evaluated.

(oil absorption)
The oil absorption was measured by the "refined linseed oil method" specified in JIS K5101-13-1.
(BET specific surface area, BJH pore volume, pore radius peak)
BET specific surface area, BJH pore volume, and peak pore radius were measured using BELSORP-mini manufactured by Bell Japan Co., Ltd. according to the above definitions.
(C value)
The C value is measured by oxidizing with flowing oxygen and helium at a temperature of 1150 ° C using elementar's vario MICRO cube, measuring the amount of carbon dioxide generated, and measuring the total amount of silica airgel as a standard ( 100% by mass).

[Evaluation method]
A panel of 10 specialists evaluated the "spreadability" and the "non-stickiness" immediately after application of each emulsion based on the following criteria. The results are shown as the average score of 10 expert panelists.
<Rating criteria: non-stickiness>
(Rating): (Evaluation)
3: Not sticky.
2: Slightly non-sticky.
1: Sticky.
<Rating criteria: elongation>
(Rating): (Evaluation)
3: Easy to stretch.
2: Slightly stretchable.
1: Hard to stretch.
<Judgment Criteria>
(Average score): (judgment)
More than 2.0: ○ 1.8 or more, less than 2.0: △
Less than 1.8: ×

[Preparation of silica airgel]
A silica airgel was prepared according to the preparation method described in JP-A-2014-218433. Table 1 shows the physical properties of the prepared silica airgel. In the following examples, unless otherwise specified, % represents % by mass.

[Example 1 and Comparative Examples 1 and 2]
With the composition shown in Table 2, emulsion cosmetics were prepared according to the order of 1 to 5 below.
1. Heat component C to 75° C. and dissolve.
2. Component A is mixed in one container and component B is mixed in another container.
3. Add component C dissolved in component B.
4. Add component A to 3.
5. Stir and mix with a homogenizer at 2000 rpm for 10 minutes.
Table 2 shows those evaluation results.

As shown in Table 2, the emulsion-like cosmetic of Example 1 was suppressed in stickiness due to the oily component, had good spreadability without a creaking feeling.

Claims (5)

An emulsion cosmetic comprising 0.01 to 0.1% by mass of silica airgel. 2. The milky lotion cosmetic according to claim 1, wherein said silica airgel has an average circularity of 0.8 or more. 3. The milky cosmetic composition according to claim 1, wherein the silica airgel has an M value of 20 or more, which indicates methanol wettability. The emulsion cosmetic according to any one of claims 1 to 3, wherein the silica airgel has a volume-based cumulative 50% diameter (D50) of 1 µm or more and 200 µm or less as measured by the Coulter Counter method. 5. The emulsion cosmetic composition according to any one of claims 1 to 4, wherein the silica airgel has an oil absorption of 400 mL/100 g or more and 800 mL/100 g or less.