JP7602340B2 - Skin cosmetics - Google Patents

Description

The present invention relates to skin cosmetics.

Agar is used as a component of cosmetics because of its unique properties such as water retention function and usability, etc. Cosmetics in which agar gel particles are dispersed have been studied.
For example, Patent Document 1 describes that a cosmetic preparation in which powder-containing agar gel particles are dispersed in an aqueous medium has agar gel particles that disintegrate easily, spread evenly on the skin, and are highly compatible with the skin.
Furthermore, Patent Document 2 describes that a cosmetic preparation in which agar gel particles containing inorganic powder and agar are dispersed in an oil-in-water emulsion composition can be smoothly applied with a constant force without the agar gel particles collapsing when applied, and provides excellent skin firmness after application.

JP 2014-181224 A JP 2014-210770 A

However, it was difficult to store conventional cosmetics with dispersed agar gel particles stably even at high temperatures. In addition, the agar gel particles were not fully satisfactory in terms of providing an appropriate hardness, i.e., keeping the particles stable in the cosmetic and making them easily crushable when applied to the skin. Furthermore, after application, the cosmetics did not blend well with the skin or adhere well to the skin, and did not provide a smooth (slippery) feel to the skin.

The present invention relates to a skin cosmetic that contains hydrogel particles, has excellent stability at high temperatures, the hydrogel particles are easily crushed during application, and has a good adhesion to the skin and a good smooth feel after application.

The inventors have found that by using hydrogel particles containing a specific amount of hyaluronic acid or a salt thereof and agar, a skin cosmetic can be obtained that has excellent stability at high temperatures, the hydrogel particles are easily crushed when applied, and has a good adhesion to the skin and a smooth feel after application.

The present invention relates to a skin cosmetic preparation containing hydrogel particles, the hydrogel particles comprising the following components (a) to (c):
(a) hyaluronic acid or a salt thereof,
(b) agar,
(c) A skin cosmetic preparation containing water and 0.01 to 0.8% by mass of component (a) in hydrogel particles.

The skin cosmetic of the present invention has excellent high-temperature stability, the hydrogel particles are easily crushed when applied, and after application it adheres well to the skin, providing a smooth feel to the skin.

The hydrogel particles used in the present invention contain the following components (a) to (c).
(a) hyaluronic acid or a salt thereof 0.01 to 0.8% by mass,
(b) agar,
(c) Water

Among the components (a), examples of the hyaluronate include alkali metal salts such as sodium and potassium. As the component (a), sodium hyaluronate is preferred from the viewpoints of availability, versatility, and improved high-temperature stability.
From the viewpoint of improving the moisturizing effect and high temperature stability, the component (a) is contained in the hydrogel particles in an amount of 0.01 to 0.8% by mass, preferably 0.03 to 0.6% by mass, and more preferably 0.05 to 0.3% by mass.

The agar of component (b) refers to hemicellulose containing galactan consisting of 1,3 and 1,4 bonds of galactose. There are no particular limitations on the agar, but the jelly strength (Nikkansui method) of the agar is preferably 147 kPa (1500 g/ ^cm2 ) or less, and more preferably 19.6 kPa (200 g/ ^cm2 ) to 127 kPa (1300 g/ ^cm2 ), from the viewpoint of improving the feel when applied to the skin. Jelly strength can be determined by preparing a 1.5% by mass aqueous solution of agar, leaving the solution at 20°C for 15 hours to solidify the gel, cutting the gel into a size of 25 mm length x 25 mm width x 3 mm height, applying a load to the cut gel using a Nissansui type jelly strength measuring device (manufactured by Kiya Seisakusho), and measuring the maximum mass (g) per 1 ^cm2 of surface area when the gel can withstand the load for 20 seconds at 20°C.
As the agar of component (b), for example, commercially available products such as Ina Agar PS-84, Z-10, AX-30, AX-100, AX-200, T-1, S-5, M-7, UP-16, CS-16A, CS-420, CS-670, and XY-908 (all manufactured by Ina Food Industry Co., Ltd.) can be used. Of these, AX-200, UP-16, CS-16A, and XY-908 are preferred.
From the viewpoints of improving high-temperature stability, ease of crushing of the hydrogel particles when applied, and adhesion and smoothness to the skin after application, the agar of component (b) is preferably contained in the hydrogel particles in an amount of 0.5 to 10 mass %, more preferably 1 to 8 mass %, even more preferably 1.5 to 7 mass %, and even more preferably 3 to 6 mass %.

In the present invention, the mass ratio (a)/(b) of component (a) to component (b) is preferably 0.001 to 1, more preferably 0.003 to 0.7, even more preferably 0.005 to 0.4, even more preferably 0.007 to 0.2, particularly preferably 0.008 to 0.13, and particularly preferably 0.01 to 0.06, from the viewpoint of improving the moldability and high-temperature stability of the hydrogel particles.

From the viewpoint of improving the moldability and high-temperature stability of the hydrogel particles and improving the handling during preparation of the hydrogel particles, the water content of the hydrogel particles is preferably 70 to 99% by mass, more preferably 80 to 98% by mass, and even more preferably 90 to 97% by mass.

The hydrogel particles may further contain (d) silica, which can improve the moldability of the hydrogel particles, provide good gel strength, and improve high-temperature stability.
The silica is preferably porous silica. The porous silica includes hollow porous silica. Commercially available porous silica products include Sunsphere series (AGC Si-Tech Co., Ltd.) and Godball series (Suzuki Yushi Kogyo Co., Ltd.).
The average particle size of the silica is preferably 0.5 to 50 μm, more preferably 3 to 30 μm, even more preferably 5 to 30 μm, and even more preferably 10 to 20 μm. The average particle size is the average particle size of the silica when monodispersed, and is the volume average particle size of the particle size measured by a static light scattering method.
From the viewpoints of improving the moldability of the hydrogel particles, the ease with which the hydrogel particles are crushed during application, and the adhesion and smoothness of the hydrogel particles to the skin after application, the silica is preferably contained in the hydrogel particles in an amount of 0.0001 to 3 mass %, more preferably 0.001 to 2 mass %, even more preferably 0.01 to 0.8 mass %, and even more preferably 0.1 to 0.35 mass %.

In the present invention, the mass ratio (a)/(d) of component (a) to component (d) is preferably 0.01 to 10, more preferably 0.15 to 6, and even more preferably 0.4 to 4, from the viewpoints of improving the moldability of the hydrogel particles, the ease with which the hydrogel particles are crushed during application, and the adhesion and smoothness of the hydrogel particles to the skin after application.

The hydrogel particles may also contain powder other than silica (component (d)), such as a coloring pigment.
The color pigments are those used in ordinary cosmetics, such as metal oxides such as titanium oxide, zinc oxide, cerium oxide, aluminum oxide, yellow iron oxide, black iron oxide, red ocher, Prussian blue, ultramarine, chromium oxide, and chromium hydroxide, metal complexes such as manganese violet and cobalt titanate, and inorganic pigments such as carbon black; Red No. 3, Red No. 104, Red No. 106, Red No. 201, Red No. 202, Red No. 204, Red No. 205, Red No. 22, and the like. Examples of the color pigments include synthetic organic pigments such as Red No. 0, Red 226, Red No. 227, Red No. 228, Red No. 230, Red No. 401, Red No. 405, Red No. 505, Orange No. 203, Orange No. 204, Orange No. 205, Yellow No. 4, Yellow No. 5, Yellow No. 401, Blue No. 1, and Blue 404; and natural organic pigments such as β-carotene, caramel, and paprika color. Examples of the color pigments include composites of these color pigments and composite pigments that combine these color pigments with pearl pigments.
As the coloring pigment, from the viewpoint of making the skin cosmetic contain hydrogel particles and have a beautiful appearance when filled into a container, metal oxides are preferred, and it is more preferred to include at least one or two or more selected from titanium oxide, zinc oxide, yellow iron oxide, black iron oxide, and red iron oxide, and it is even more preferred to include at least one or two or more selected from titanium oxide, yellow iron oxide, black iron oxide, and red iron oxide.

Furthermore, powders other than the silica and color pigment of component (d) may also be contained. For example, inorganic powders include magnesium oxide, zirconium oxide, magnesium carbonate, calcium carbonate, aluminum silicate, magnesium silicate, aluminum magnesium silicate, mica, synthetic mica, sericite, talc, kaolin, silicon carbide, barium sulfate, bentonite, smectite, titanium mica, and boron nitride.
Examples of organic powders include bismuth oxychloride, organic pigment-coated mica titanium, nylon powder, polymethyl methacrylate, acrylonitrile-methacrylic acid copolymer powder, polyethylene powder, polystyrene powder, organopolysiloxane elastomer powder, polymethylsilsesquioxane powder, polyurethane powder, silk powder, crystalline cellulose, and N-acyl lysine.
Furthermore, the composite powder may include barium sulfate-coated mica titanium.
As the powder other than silica and color pigments of component (d), from the viewpoint of making the appearance of the hydrogel particles appear beautiful when the skin cosmetic is filled into a container, it is preferable to include at least one or more types selected from mica, synthetic mica, and titanium mica, and it is more preferable to include at least one or more types selected from mica and synthetic mica.

The hydrogel particles may further contain, in addition to the above components, components commonly used in cosmetics, such as surfactants, polyhydric alcohols, oils, and polymers other than component (a).

Hydrogel particles can be produced, for example, by adding agar and hyaluronic acid or a salt thereof to purified water, mixing and stirring, and dissolving by heating at 95°C or higher, and then adding silica, coloring pigments, etc., as necessary, and mixing and stirring again, passing the mixture through a mesh as necessary, and then dropping the mixture at a constant flow rate into a cooled and circulated oil liquid at 20°C or lower.

The hydrogel particles thus obtained are preferably 0.08 to 4 mm in particle size, more preferably 0.2 to 2.5 mm, and even more preferably 0.5 to 2 mm, from the viewpoints of providing a beautiful appearance when the particles are contained in a skin cosmetic and filled into a container, improving ease of ejection, ease of crushing during application, and improving the adhesion and smoothness of the particles to the skin after application.
Here, the particle size is measured by means of a vernier caliper.

In addition, from the viewpoint of improving high-temperature storage stability, ease of crushing of the hydrogel particles during application, adhesion to the skin after application, and smoothness, the hydrogel particles preferably have a softening point of 30°C or higher, more preferably 35°C or higher, even more preferably 38°C or higher, even more preferably 48°C or higher, and especially preferably 58°C or higher. Also, the softening point is preferably 68°C or lower, more preferably 65°C or lower, and even more preferably 63°C or lower.

The softening point is determined as follows.
First, 50 g of a softening point confirmation aqueous solution containing hydrogel particles and having the following composition is prepared, filled into a vial (made of colorless transparent glass), and stored in a thermostatic bath at each temperature for one month. After that, while maintaining each temperature, a stirring rod is inserted into the vial, and the mixture is stirred in a circular motion at a speed of once per second for 5 minutes, and the shape of the hydrogel particles is visually confirmed to be spherical or not. For example, if the shape of the hydrogel particles is spherical at a certain temperature (A°C) and the shape is not maintained at a temperature higher than that, that temperature (A°C) is determined as the softening point.
At the start of storage, the hydrogel particles are suspended in the aqueous solution for confirming the softening point.

(Composition of aqueous solution for confirming softening point)
0.2% by mass of carboxyvinyl polymer,
Potassium hydroxide 0.07% by mass,
phenoxyethanol 0.3% by mass,
Hydrogel particles 5.0% by mass,
・Water Residual

In the skin cosmetic of the present invention, the content of the hydrogel particles in the skin cosmetic is preferably 1 to 20% by mass, more preferably 1.5 to 15% by mass, and even more preferably 2 to 10% by mass, from the viewpoints of improving the appearance of the cosmetic, ease of discharging from a container, high-temperature stability, ease of crushing of the hydrogel particles during application, and the adhesion and smoothness of the skin after application.

The skin cosmetic of the present invention may contain, in addition to the hydrogel particles, ingredients that are commonly used in cosmetics, such as hydrophilic surfactants, water-soluble thickeners, polyhydric alcohols, and the like.
As the hydrophilic surfactant, a nonionic surfactant having an HLB of 10 to 18 is preferred, an HLB of 11 to 16 is more preferred, and an HLB of 12 to 15 is even more preferred.
Here, HLB (Hydrophilic-Lipophilic Balance) indicates the molecular weight of the hydrophilic group portion in the total molecular weight of the surfactant, and is calculated by Griffin's formula. When a surfactant is composed of two or more nonionic surfactants, the HLB of the mixed surfactant is calculated as follows. The HLB of the mixed surfactant is the phase arithmetic average of the HLB values of the individual nonionic surfactants based on their blending ratio.
Mixed HLB=Σ(HLBx×Wx)/ΣWx
HLBx indicates the HLB value of nonionic surfactant X.
Wx represents the mass (g) of the nonionic surfactant X having a value of HLBx.

Examples of such nonionic surfactants include polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, polyoxyethylene fatty acid ester, polyoxyethylene alkanol ether, polyglycerin fatty acid ester, sucrose fatty acid ester, etc. Among these, from the viewpoint of improving high temperature stability, ease of crushing of hydrogel particles during application, and adhesion and smoothness to the skin after application, it is preferable to include one or more selected from polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, and polyoxyethylene fatty acid ester, more preferably to include one or more selected from polyoxyethylene hydrogenated castor oil and polyoxyethylene alkyl ether, and even more preferably to include polyoxyethylene hydrogenated castor oil.

Hydrophilic surfactants can be used alone or in combination of two or more. The content in the skin cosmetic is preferably 0.1 to 3% by mass, more preferably 0.2 to 2% by mass, and even more preferably 0.3 to 1% by mass, from the viewpoints of improving high-temperature stability, ease of crushing of hydrogel particles during application, and adhesion and smoothness to the skin after application.

Examples of water-soluble thickeners include carrageenan, dextrin, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, polyvinyl alcohol, polyacrylic acid, polymethacrylic acid, alkyl-modified carboxyvinyl polymer, carboxyvinyl polymer, xanthan gum, carboxymethyl chitin, chitosan, etc. Among these, from the viewpoints of improving high-temperature stability, ease of crushing of hydrogel particles during application, adhesion and smoothness to the skin after application, and uniform dispersion of hydrogel particles in the skin cosmetic, it is preferable to include one or more types selected from alkyl-modified carboxyvinyl polymer and carboxyvinyl polymer, and it is more preferable to include carboxyvinyl polymer.

In addition, it is preferable to use acid-type water-soluble thickeners such as polyacrylic acid, alkyl-modified carboxyvinyl polymers, and carboxyvinyl polymers as water-soluble or water-dispersible salts using potassium hydroxide or the like as a neutralizing agent.

One or more water-soluble thickeners may be used, and the content in the skin cosmetic is preferably 0.01 to 1% by mass, more preferably 0.05 to 0.8% by mass, and even more preferably 0.1 to 0.5% by mass, from the viewpoints of improving high-temperature stability, ease of crushing of hydrogel particles during application, adhesion to the skin after application, and smoothness, and uniformly dispersing the hydrogel particles in the skin cosmetic.

A polyhydric alcohol is a compound having two or more hydroxyl groups in the molecule.
Examples of dihydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, 1,3-butylene glycol, and 1,3-propanediol. Examples of trihydric alcohols include glycerin and trimethylolpropane. Examples of tetrahydric alcohols include diglycerin and erythritol. Examples of polyhydric alcohols having a valence of five or more include polyglycerins such as triglycerin; sugars and sugar alcohols such as glucose, maltose, maltose, sucrose, xylitol, sorbitol, malbitol, polyoxyethylene methyl glucoside, polyoxyethylene ethyl glucoside, and polyoxyethylene propylene glucoside.

Among these, from the viewpoints of improving high-temperature stability, ease of crushing of hydrogel particles during application, and adhesion and smoothness to the skin after application, it is preferable to include one or more types selected from dihydric, trihydric and tetrahydric alcohols, more preferably to include one or more types selected from dihydric and trihydric alcohols, even more preferably to include one or more types selected from propylene glycol, 1,3-butylene glycol, dipropylene glycol and glycerin, even more preferably to include one or two types selected from dipropylene glycol and glycerin, and particularly preferably to include dipropylene glycol.
One or more types of polyhydric alcohols can be used, and the content thereof in the skin cosmetic is preferably 1 to 15% by mass, more preferably 2 to 12% by mass, and even more preferably 3 to 8% by mass, from the viewpoints of improving high-temperature stability, ease of crushing of the hydrogel particles during application, and adhesion and smoothness to the skin after application.

In the skin cosmetic of the present invention, the content of water contained other than the hydrogel particles is preferably 70 to 98% by mass of the total composition, more preferably 80 to 96% by mass, and even more preferably 85 to 94% by mass, from the viewpoint of improving the stability and refreshing feeling of the skin cosmetic.

In addition to the above-mentioned components, the skin cosmetic of the present invention may contain components used in ordinary cosmetics, such as oily components, antioxidants, fragrances, preservatives, pH adjusters, blood circulation promoters, cooling agents, antiperspirants, germicides, skin activators, moisturizers, and cooling agents.

The skin cosmetic of the present invention can be manufactured by blending hydrogel particles and using a conventional method. For example, it can be manufactured by adding ingredients other than the hydrogel particles while stirring purified water with a homogenizer, further stirring with the homogenizer, and then adding the hydrogel particles and slowly stirring with a paddle mixer to make it homogenous.

The skin cosmetic of the present invention can be used for various purposes and in various forms, for example, as an O/W emulsion cosmetic, an aqueous cosmetic, a gel cosmetic, a cream, an emulsion, a lotion, a beauty essence, a foundation, and the like.
The skin cosmetic of the present invention has hydrogel particles uniformly dispersed in the cosmetic. When filled in a pump container, the hydrogel particles are crushed on the skin when discharged from the container or when applied, and the skin blends well with the skin after application, providing a smooth feel.

Examples 1 to 7 and Comparative Examples 1 to 2
A skin cosmetic (serum) having the composition shown in Table 1 was produced using hydrogel particles having the composition shown in Table 2. The resulting hydrogel particles were evaluated for particle size and softening point, and the resulting skin cosmetic was evaluated for high temperature stability, ease of crushing of the hydrogel particles during application, adhesion to the skin after application, and smoothness of the skin after application. The results are also shown in Table 2.

(Production method)
(1) Preparation of hydrogel particles:
(a) Sodium hyaluronate and (b) agar were added to purified water and mixed with stirring.
After that, the mixture was heated to 95°C and dissolved with stirring, and then (d) silica and a color pigment were added and stirred to obtain a mixed liquid.
The resulting mixture was cooled to 25°C and then sieved through a 140 mesh sieve.
After that, the sieved mixture was heated to 70°C and added dropwise at a constant flow rate to an oil liquid that was cooled and circulated at 20°C to obtain solidified hydrogel particles.
The oily liquid adhering to the surface of the hydrogel particles was washed off with running water.

(2) Production of skin cosmetics:
While stirring purified water at room temperature with a homomixer, the ingredients other than the hydrogel particles were added and further stirred with the homomixer. After that, the hydrogel particles were added and further stirred slowly with a paddle mixer to make the mixture homogenous, thereby obtaining a skin cosmetic preparation.

(Evaluation Method)
(1) Particle size of hydrogel particles:
Five particles were randomly selected from the produced hydrogel particles, and the particle sizes were measured with a vernier caliper, and the average value was shown.

(2) Softening point of hydrogel particles:
50 g of a softening point confirmation aqueous solution containing hydrogel particles and having the following composition was prepared, filled into a vial (made of colorless transparent glass), and stored in a thermostatic bath set at temperatures increments of 5°C in the range of 25°C to 75°C for one month. Thereafter, a stirring rod was placed in the vial while maintaining the temperature, and the mixture was stirred in a circular motion at a speed of once per second for 5 minutes, and the state of the hydrogel particles at each storage temperature was visually confirmed to determine the softening point. The softening point indicates the temperature at which the shape of the hydrogel particles was maintained after the above operation. For example, a softening point of 60°C indicates that the hydrogel particles stored in a thermostatic bath at 60°C after the above operation were able to maintain their shape, while the hydrogel particles stored in a thermostatic bath at 65°C were unable to maintain their shape.

(Composition of aqueous solution for confirming softening point)
Carboxyvinyl polymer: 0.2% by mass
Potassium hydroxide 0.07% by mass
Phenoxyethanol 0.3% by mass
Hydrogel particles: 5.0% by mass
・Water Residual (At the start of storage, the hydrogel particles were floating in the aqueous solution used to check the softening point)

(3) High temperature stability (50℃):
50 g of each skin cosmetic preparation was placed in a vial (made of colorless transparent glass) and stored at 50° C. for one month.
After storage, the hydrogel particles in the skin cosmetic preparation were visually observed and evaluated according to the following criteria.
At the start of storage, the hydrogel particles are spherical.
◯: The spherical shape is maintained.
△: The spherical shape is not maintained.
×: The spherical shape was clearly not maintained.

(4) Ease of crushing hydrogel particles when applied:
Ten expert evaluators applied each skin cosmetic preparation to the skin and evaluated the crushability of the hydrogel particles according to the following criteria. The results are shown as the average of the 10 evaluators.
5: Obviously easily crushed.
4: Easily crushed.
3: Somewhat crushable.
2: Not easily crushed.
1: Obviously not crushed.

(5) Adhesion to skin after application:
Ten expert evaluators applied each skin cosmetic preparation to the skin and then evaluated its adhesion to the skin according to the following criteria. The results are shown as the average of the 10 evaluators.
The feeling of adhesion to the skin refers to the feeling of the skin sticking to the skin when a finger is pressed against the skin.
5: There is a clear sense of adhesion.
4: Feels tight.
3: There is a slight feeling of adhesion.
2: There is not much adhesion.
1: There is clearly no adhesion.

(6) Smooth feeling on skin after application:
After applying each skin cosmetic preparation to the skin, ten expert evaluators evaluated the smoothness of the skin according to the following criteria. The results are shown as the average of the ten experts' evaluations.
The smoothness of the skin refers to the ability of the finger to move smoothly when touching the skin with the fingertips without any resistance due to stickiness or a squeaky feeling.
5: There is a clear feeling of smoothness.
4: Feels smooth.
3: Slightly smooth feel.
2: Not very smooth.
1: Clearly no smoothness.

Prescription Examples 1 to 4
Skin cosmetics were produced having the compositions shown in Tables 3 to 6. The hydrogel particles were all produced in the same manner as in Examples 1 to 7.
All of the obtained skin cosmetics have excellent high temperature stability, the hydrogel particles are easily crushed when applied, and after application, they blend well with the skin, have excellent adhesion, and provide a smooth feel.

Formulation example 1 (transparent gel)
A is uniformly dispersed at room temperature using a homomixer, B and C are added, and the mixture is further dispersed using a homomixer. Finally, D is added and slowly stirred using a paddle mixer to make the mixture uniform, producing a transparent gel.

Formulation example 2 (cream)
After heating A and B to 80°C, add B to A and disperse using a homomixer. Then add C and E and disperse using a homomixer. Cool to 45°C, add D and F and disperse using a homomixer. Finally, add G and slowly mix with a paddle mixer until homogenous, to produce a cream.

Formulation example 3 (lotion)
After heating A and B to 80°C, add B to A and disperse using a homomixer. Next, add C and E and disperse using a homomixer. Cool to 45°C, add D and F and disperse using a homomixer. Finally, add G and slowly stir using a paddle mixer until homogenous, to produce an emulsion.

Formulation example 4 (serum)
A is uniformly dispersed at room temperature using a homomixer, B and C are added, and the mixture is further dispersed using a homomixer. Finally, D is added and the mixture is slowly stirred using a paddle mixer to make the mixture uniform, thereby producing a beauty essence.

Claims (6)

A skin cosmetic containing hydrogel particles, the hydrogel particles comprising the following components (a) to (c):
(a) hyaluronic acid or a salt thereof,
(b) agar,
(c) A skin cosmetic preparation containing water and containing 0.05 to 0.8% by mass of component (a) and 1 to 6% by mass of component (b) in hydrogel particles. The skin cosmetic according to claim 1, wherein the average particle size of the hydrogel particles is 0.08 to 4 mm. The skin cosmetic according to claim 1 or 2, wherein the softening point of the hydrogel particles is 30°C or higher. 4. The skin cosmetic composition according to claim 1, wherein the mass ratio of component (a) to component (b) [(a)/(b)] is 0.008 to 0.7 . The skin cosmetic according to any one of claims 1 to 4, wherein the content of hydrogel particles in the skin cosmetic is 1 to 20% by mass. The skin cosmetic preparation according to any one of claims 1 to 5, wherein the hydrogel particles further contain (d) silica, and the hydrogel particles contain 70 to 98 mass% of component (c) and 0.1 to 2 mass% of component (d).