TW202312973A - Hydrogel - Google Patents

Abstract

The present invention provides a hydrogel, the hydrogel containing the following components, (A), (B), (C), and (D): (A) an anionic polymer; (B) a trivalent metal salt and/or a borate; (C) a nonionic surfactant the IOB value of which is greater than 0.1 and less than 2; and (D) water.

Description

Hydrogels

The present invention relates to a hydrogel.

In China, as there are more and more facial mask products, consumers' awareness of facial mask categories has gradually increased and they have begun to use facial mask products as a necessity for skin care steps.

Wherein, although the use of non-woven cloth impregnated with essence has a better skin care effect, when in use, in order to make the facial mask stick to the face obediently, it is necessary to adjust the application position many times, which is troublesome to use. Moreover, since the essence must be exuded from the non-woven fabric to achieve the skin care effect, the touch of these facial masks is also very sticky, which has been criticized by consumers.

On the other hand, some gel mask materials are usually only suitable for sticking to a certain part of the face, such as the eye area. It uses a material that is fixed and cannot change its shape, which cannot meet the diverse and flexible needs of consumers.

Therefore, consumers are in urgent need of facial mask products that have a good feeling of use, neither dryness nor stickiness, and maintain the original skin care function, and can be conveniently applied to any position on the face. [Prior Art Literature] [Patent Document]

Patent Document 1: CN 110430859A Patent Document 2: CN 101002722A

In view of the above circumstances, the object of the present invention is to provide a hydrogel, which has both excellent non-sticky and non-dry feeling, and can achieve good touch and use feeling. Furthermore, it can be easily applied anywhere on the face.

The inventors of the present case found that by including non-ionic surfactant in the hydrogel, the feeling of dryness and stickiness can be improved, so that a hydrogel without stickiness and dryness when used on the skin can be obtained.

The present invention provides a hydrogel, which contains the following components (A), (B), (C) and (D): (A) anionic polymers; (B) Trivalent metal salts and/or borates; (C) nonionic surfactants with an IOB value of 0.1 or more and 2 or less; and (D) water.

The inventors of this case have not clarified the mechanism why the hydrogel of the present invention can achieve excellent non-sticky and dry feeling, but speculate as follows: the main reason for the dry feeling of the hydrogel is the trivalent Metal ions or borate anions, however, when a nonionic surfactant is included in the hydrogel, the lipophilic end of the surfactant exhibits good skin affinity, thereby reducing the blocking feeling caused by the ions. On the other hand, after the addition of surfactants, the hydrogel has a greasy feeling, thereby improving the sticky feeling.

In addition, the present invention also provides the use of the hydrogel as an external preparation for skin.

Furthermore, the present invention also provides a skin care method for applying the hydrogel of the present invention to the skin.

The hydrogel of the present invention and its preparation method and usage method are described in detail below.

＜Hydrogel＞ [ingredient (A)] Component (A) used in the present invention is an anionic polymer, and since its molecular chain contains a certain number of polar groups, it can form a large network structure with other ions through charge neutralization.

As an anionic polymer of a component (A), 1 type or 2 or more types selected from the following components (A1), (A2), and (A3) are mentioned, for example. (A1) anionic polyvinyl alcohol; (A2) an acrylic copolymer obtained by polymerizing at least one monomer selected from acrylic acid, methacrylic acid, and alkyl acrylates with 1 to 30 alkyl carbon atoms; (A3) Carboxymethylcellulose.

The carboxyl groups present in the components (A1), (A2), and (A3) are polar groups, and when other ions exist in the solution, the carboxyl groups will combine with other ions to form a three-dimensional network structure.

Composition (A1) The hydrogel of the present invention contains anionic polyvinyl alcohol as component (A1).

The component (A1) is, for example, polyvinyl alcohol having anionic groups such as sulfonic acid groups, sulfuric acid groups, carboxyl groups, phosphoric acid groups, and phosphonic acid groups.

Component (A1) is preferably a polyvinyl alcohol having at least one anionic group among a sulfonic acid group and a carboxyl group, and more preferably a polyvinyl alcohol having a carboxyl group, from the viewpoint of suppressing stickiness.

In the present invention, an anionic group refers to an anionic group itself or a group that can be freed to become an anionic group.

As polyvinyl alcohol having a carboxyl group, for example: (1) a product obtained by graft polymerization or block polymerization of polyvinyl alcohol and an unsaturated monomer having a carboxyl group; (2) a mixture of a vinyl ester compound and A product obtained by saponification after copolymerization of unsaturated monomers having at least one group selected from carboxyl groups and carboxylate groups; (3) after polymerizing vinyl ester compounds with chain moving agents with carboxyl groups, a product obtained by saponification; and (4) a product obtained by reacting polyvinyl alcohol with a carboxylating agent, and the like.

Examples of the unsaturated monomer having a carboxyl group used in the method (1) and (2) above, and the unsaturated monomer having a carboxylate group used in the method (2) include, for example, maleic acid , fumaric acid, itaconic acid and other ethylenically unsaturated dicarboxylic acids; Esters; Ethylenically unsaturated dicarboxylic acid diesters such as dialkyl maleate, dialkyl fumarate, and dialkyl itaconic acid; Ethylenically unsaturated carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride ; Unsaturated monocarboxylic acids such as (meth)acrylic acid, unsaturated monocarboxylic acid esters such as alkyl (meth)acrylate, etc. In addition, salts of the above compounds can also be used as the unsaturated monomer having at least one selected from carboxyl groups and carboxylate groups. These compounds may be used alone or in combination of two or more.

Examples of the vinyl ester compound used in the above (2) method and (3) method include vinyl acetate, vinyl formate, vinyl acrylate, vinyl neodecanoate, and trimethylvinyl acetate. Among these, vinyl acetate is preferable from the viewpoint of reactivity during synthesis and easy availability. These compounds may be used alone or in combination of two or more.

Examples of the carboxylating agent used in the method (4) above include succinic anhydride, maleic anhydride, acetic anhydride, trimellitic anhydride, phthalic anhydride, pyromellitic anhydride, glutaric anhydride, and hydrogenated phthalic anhydride. , Naphthalene dicarboxylic anhydride and other carboxylic anhydrides. These may be used alone or in combination of two or more.

Regarding the amount of anionic groups in anionic polyvinyl alcohol (from the ratio of monomers having anionic groups), from the viewpoint of further suppressing the sticky feeling and improving the water retention capacity and gel strength, it is preferably 0.1 mol% or more, more preferably 0.5 mol% or more, and more preferably 1 mol% or more, from the viewpoint of improving adhesion, increasing water supply, and moisturizing feeling when applied to the skin In other words, it is preferably less than 10 mol%, more preferably less than 5 mol%, and more preferably less than 3 mol%. The amount of the anionic group in the anionic polyvinyl alcohol can be determined by analyzing the anionic polyvinyl alcohol before saponification using 1H-NMR (solvent: CDCl ₃ ).

From the viewpoint of further suppressing the sticky feeling and improving the water retention capacity and gel strength, the degree of saponification of anionic polyvinyl alcohol is preferably at least 90 mole %, more preferably at least 95 mole %, and even more preferably It is more than 98 mole%. The upper limit of the degree of saponification is not particularly limited, and is, for example, 100.0 mol% or less, preferably 99.9 mol% or less, and more preferably 99.5 mol% or less. The saponification degree of anionic polyvinyl alcohol can be measured according to JIS K 6726:1994.

From the viewpoint of suppressing stickiness and improving water retention and gel strength, the degree of polymerization of anionic polyvinyl alcohol is preferably 100 or more, more preferably 500 or more, and more preferably 1000 or more. From the standpoint of improving flexibility and extensibility, it is preferably at most 200,000, more preferably at most 10,000, and even more preferably at most 4,000. The degree of polymerization of anionic polyvinyl alcohol can be calculated from the relative viscosity of an aqueous solution of completely saponified polyvinyl alcohol and water (see JIS K 6726: 1994).

Specific examples of anionic polyvinyl alcohol include KL-118, KL-318, KL-506, KM-118, and KM-618 manufactured by KURARAY Co., Ltd.; GOHSENX CKS50 and GOHSENX T manufactured by Mitsubishi Chemical Corporation. -330H, GOHSENX T-330, and GOHSENX T-350; AP-17, AT-17, and AF-17 manufactured by JAPAN VAM&POVAL CO., LTD.

In the present invention, the component (A1) may be used alone or in combination of two or more.

From the viewpoint of obtaining appropriate hardness, the viscosity of component (A1) anionic polyvinyl alcohol in a 4% aqueous solution (Brookfield viscometer, S61 rotor, 20 rpm) at 20°C is preferably 10 mPa‧s or more, more preferably 20 mPa‧s or more, more preferably 25 mPa‧s or more; from the viewpoint of obtaining appropriate softness, the viscosity is preferably 50 mPa‧s or less, more preferably 40 mPa‧s or less, and still more preferably Below 35 mPa‧s. Therefore, from the viewpoint of both appropriate hardness and softness, the viscosity is preferably 10-50 mPa‧s, more preferably 20-40 mPa‧s, and more preferably 25-35 mPa‧s.

From the viewpoint of obtaining appropriate hardness, in the hydrogel of the present invention, the content of component (A1) is 5% by mass or more, preferably 8% by mass or more and 20% by mass or less, preferably 12% by mass the following. Based on the above viewpoints, in the hydrogel of the present invention, the content of component (A1) is not less than 5% by mass and not more than 20% by mass, preferably not less than 8% by mass and not more than 12% by mass.

Composition (A2) Component (A2) is an acrylic copolymer obtained by polymerizing at least one monomer selected from acrylic acid, methacrylic acid, and alkyl (meth)acrylates with 1 to 30 alkyl carbon atoms. The acrylic polymer of component (A2) includes polyacrylic acid, sodium polyacrylate, cross-linked sodium polyacrylate, carbomer, and acrylic resin.

Polyacrylic acid is a polymer formed by addition polymerization of acrylic acid monomers, and sodium polyacrylate is obtained by neutralizing polyacrylic acid with sodium hydroxide. As polyacrylic acid and sodium polyacrylate, the molecular weight is preferably 100~4000000, and the viscosity is preferably 100~50000 mPa‧s (0.5% aqueous solution, 25°C, Brookfield viscometer S61~S64 rotor, the rotor and speed are based on the measured object The viscosity size is differently selected), its commercially available products can be for example 323667, 181285, 306215, 306231, 306223, 447013, 420344, 81123 etc. of Merck; AC-10H and Jurymer AC-10LHP of Nihon Junyaku Company; Synthron Modarez V 1300 PX of the company; Oristar PALA of Orient Stars; Creagel TN 500 of C.I.T., etc.

Carbomer is a polyacrylic acid polymer, which is a high molecular weight cross-linked homopolymer. The viscosity is preferably 500~80000 mPa‧s (0.2% aqueous solution, 25°C, pH adjusted to neutral with KOH, Brookfield viscometer S61~S64 rotor, the rotor and speed are selected according to the viscosity of the measured object), its market For example, Lubrizol's Ultrez 10, Ultrez 21, Ultrz 30, etc. can be sold.

Acrylate copolymer is a polymer obtained by copolymerizing monomers such as methacrylate, acrylate, and acrylic acid in proportion. In the present invention, both methacrylate and acrylate are alkyl (meth)acrylates with alkyl carbon atoms of 1 to 30, among which, methyl (meth)acrylate, (methyl) Ethyl acrylate, butyl (meth)acrylate, C10-30 alkyl acrylate. As an acrylate copolymer, the viscosity is preferably 100~80000 mPa‧s (0.2% aqueous solution, 25°C, adjust the pH to neutral with KOH, Brookfield viscometer S61~S64 rotor, the rotor and speed are based on the viscosity of the measured object Different selection), its commercially available products can be for example Pemulen TR-1, Pemulen TR-2, SF-1, SF-2, ETD 2020 of Lubrizol Company, etc., ACULYN 88, ACULYN 22, ACULYN of Rohm and Haas Company, etc. ACULYN 28, ACULYN 38, etc.

From the viewpoint of obtaining appropriate hardness, in the hydrogel of the present invention, the content of component (A2) is not less than 0.1% by mass and not more than 20% by mass, preferably not more than 15% by mass. Based on the above viewpoints, in the hydrogel of the present invention, the content of component (A2) is not less than 0.1% by mass and not more than 20% by mass, preferably not less than 0.1% by mass and not more than 15% by mass.

Composition (A3) Component (A3) is carboxymethylcellulose (CMC), which is a cellulose ether compound obtained by carboxymethylating cellulose.

From the point of view of obtaining appropriate hardness, the 1% aqueous solution of component (A3) carboxymethyl cellulose at 20°C (Brookfield Viscometer S61~S64 rotor, the rotor and speed are selected according to the viscosity of the measured object) The viscosity is above 200 mPa‧s; from the viewpoint of obtaining appropriate softness, the viscosity is preferably below 5000 mPa‧s. Therefore, from the viewpoint of obtaining appropriate hardness and softness, the viscosity is preferably 200~5000 mPa‧s.

As carboxymethyl cellulose, commercially available products thereof include Ashland's Aqualon, Blanose, and Bondwell series, such as TH10A, 9H4FU, and the like.

From the viewpoint of obtaining appropriate hardness, the content of the component (A3) in the hydrogel of the present invention is not less than 0.2% by mass and not more than 20% by mass, preferably not more than 15% by mass. Based on the above viewpoints, in the hydrogel of the present invention, the content of component (A3) is not less than 0.2% by mass and not more than 20% by mass, preferably not less than 0.5% by mass and not more than 15% by mass.

In the present invention, component (A) is one or more selected from components (A1), (A2) and (A3), preferably component (A) is polyvinyl alcohol.

From the viewpoint of obtaining a hydrogel with a suitable viscosity, in the hydrogel of the present invention, the total content of components (A) is not less than 0.1% by mass, preferably not less than 0.5% by mass, and not more than 30% by mass, Preferably it is 20 mass % or less. Based on the above viewpoints, in the hydrogel of the present invention, the total content of components (A) is not less than 0.1% by mass and not more than 30% by mass, preferably not less than 0.5% by mass and not more than 20% by mass.

[ingredient (B)] The component (B) used in this invention is 1 type or 2 or more types selected from a trivalent metal salt and a borate.

Examples of the trivalent metal salt of component (B) used in the present invention include iron salts containing iron ions (Fe ³⁺ ), manganese salts containing manganese ions (Mn ³⁺ ), manganese salts containing chromium ions (Cr ³⁺ ), aluminum salts containing aluminum ions (Al ³⁺ ), etc. Among them, aluminum salts containing aluminum ions (Al ³⁺ ) are preferred from the viewpoint of easy availability.

Examples of aluminum salts include aluminum chloride, potassium alum, ammonium alum, aluminum acetate, aluminum magnesium methyl silicate, aluminum magnesium silicate, aluminum magnesium metasilicate, aluminum EDTA, aluminum allantoin, and aluminum hydroxide 1 or more of aluminum magnesium hydroxide, p-hydroxyaluminum acetic acid, aluminum sulfate, potassium aluminum sulfate, aluminum lactate, aluminum glycolate, aluminum glycinate, aluminum oxide, and aluminum borate.

Among these, aluminum chloride, potassium alum, ammonium alum, aluminum acetate, aluminum magnesium methyl silicate, aluminum allantoin, aluminum sulfate, potassium aluminum sulfate, aluminum lactate, Aluminum glycinate, aluminum glycinate, more preferably aluminum chloride, aluminum sulfate, potassium alum, aluminum glycinate, further preferably aluminum chloride, aluminum sulfate.

When the trivalent metal salt is dissolved in water, trivalent metal ions are released; when the aqueous solution of component (A) anionic polymer is mixed with the aqueous solution of component (B) trivalent metal salt, an irreversible gelation reaction will occur. Wherein the trivalent metal ion in the trivalent metal salt reacts with the carboxylate in the component (A) to form a covalent coordination bond, thereby forming a network gel.

As the borate in the component (B) used in the present invention, mainly include tetraborate (M[B ₄ O ₅ (OH) ₄ ], M is sodium, potassium or ammonium) and pentaborate (M[B ₅ O ₆ (OH) ₄ ], M is sodium, potassium or ammonium), from the viewpoint of obtaining convenience, sodium tetraborate is preferred. As a commercial item, BORAX by Wako Pure Chemical Industry Co., Ltd. etc. are mentioned, for example.

When borate is dissolved in water to form a borate aqueous solution, the borate anions in the aqueous solution mainly include [B(OH) ₄ ] ^- , [B ₃ O ₃ (OH) ₄ ] ^- , [B ₄ O ₅ (OH) ₄ ] ^2- , [B ₅ O ₆ (OH) ₄ ] ^- etc.

An irreversible gelation reaction occurs when the aqueous solution of the anionic polymer of component (A1) is mixed with the aqueous solution of the borate of component (B). Wherein, the trivalent boron ion in the borate forms a covalent coordination bond with the hydroxyl group in the component (A1), thereby forming a network gel.

The hydrogel obtained through coordination covalent bonding can obtain appropriate hardness and ductility, and can maintain its shape even if it is attached to the skin for a long time.

Component (B) is dissolved in water and used as an aqueous solution. In addition, component (B) may be used alone or in combination of two or more. From the viewpoint of the ductility of the hydrogel, in the hydrogel of the present invention, the content of component (B) is 0.2% by mass or more, and 3% by mass or less. Based on the above viewpoints, in the hydrogel of the present invention, the content of the component (B) is 0.2% by mass or more and 3% by mass or less.

Therefore, from the viewpoint of ensuring the stability of the network structure of the hydrogel, regarding the relationship between the component (B) and the component (A), the molar amount of the trivalent metal ion contained in the component (B) is relative to the component ( A) The ratio of the molar amount of the carboxyl group contained (the molar amount of the trivalent metal ion of (B)/the molar amount of the carboxyl group of (A)) is 0.5-10, preferably 3-6. The ratio is obtained by the following method: first, with respect to the trivalent metal ions in the component (B), calculate the molar amount of the trivalent metal ions in the component (B), and record it as M1; The molar amount of the group is obtained by measuring the molar amount of carboxyl groups in the component (A1), and is denoted as M2; the above-mentioned molar ratio is obtained by dividing M1 by M2.

On the other hand, from the viewpoint of securing the stability of the network structure of the hydrogel, the mass ratio of component (B) to component (A) (content of (B)/content of (A)) is 0.001 to 0.5 , preferably 0.01~0.06.

[ingredient (C)] The component (C) used in this invention is a nonionic surfactant whose IOB value is 0.1-2.

The non-ionic surfactant system with IOB being 2 or less has surface activity and shows hydrophilic-lipophilic amphiphilicity. When added to the gel system, the skin feeling shown by the non-ionic surface-active lipophilic end is silky, which is similar to It has a strong affinity for the skin, thereby exerting the advantages of improving stickiness and dryness. When IOB is higher than 2, the interfacial activity of non-ionic surfactant reduces, has very strong water-soluble ability, and the smooth feeling shown by its lipophilic end reduces, and the effect of improving dry feeling is not good. When the IOB value is lower than 0.1, it is not conducive to the stability of the gel system. From the viewpoint of realizing the non-sticky and dry feeling of the hydrogel, the IOB value of the nonionic surfactant is 2.0 or less, preferably 1-1.5, more preferably 1.16-1.37. From the viewpoint of gel system stability, the IOB value of the nonionic surfactant is 0.1 or more.

As the nonionic surfactant of component (C), specific examples include: PEG fatty acid esters, PEG hydrogenated castor oil, PEG fatty acid glycerides, PPG dextrose, PPG polyglyceryl ether, polyglycerol fatty acid esters, PEG Dimethicone, sorbitan fatty acid ester, PEG sorbitan fatty acid ester, polysorbate, fatty alcohol polyether, glucoside. Among them, PEG fatty acid esters, PEG fatty acid glycerides, and the like are preferred.

As the nonionic surfactant of component (C), specific examples include: PPG-9 diglyceryl ether (IOB value: 0.90), PPG-10 methyl glucose ether (IOB value: 0.95), PEG-7 glycerin Cocoate (IOB Value: 1.16), PEG-6 Caprylic/Capric Glycerides (IOB Value: 1.25), PEG-60 Castor Oil (IOB Value: 1.36), PEG-12 Laurate (IOB Value: 1.37 ), polyglyceryl-6 distearate (IOB value: 0.76), PEG-11 methyl ether polydimethylsiloxane (IOB value: 1.45), sorbitol laurate (IOB value: 0.86), PEG -6 Sorbitan Stearate (IOB Value: 0.96), Polysorbate-40 (IOB Value: 1.56), Laureth-9 (IOB Value: 1.34), Ceteareth -13 (IOB value: 1.42), decyl glucoside (IOB value: 1.57), etc.

Component (C) can be used alone or in combination of two or more, and its content is 2.0% by mass or more in the total composition, preferably 3.0 mass % or more, and 10.0 mass % or less, preferably 5.0 mass % or less. Based on the above viewpoints, in the hydrogel of the present invention, the content of component (C) is not less than 2.0% by mass and not more than 10.0% by mass, preferably not less than 2.0% by mass and not more than 5.0% by mass, more preferably not less than 2.0% by mass And 4.0% by mass or less.

In addition, from the viewpoint of improving both sticky feeling and dry feeling, the mass ratio of component (C) to the content of component (A) [content of component (C)/content of component (A)] is 0.15 to 2.0 , preferably 0.15~0.5.

[ingredient (D)] The component (D) used in this invention is water.

Examples of the component (D) water used in the present invention include water commonly used in the field of cosmetics such as deionized water, distilled water, high-purity water, and ultra-pure water.

In the present invention, the content of the component (D) water in the hydrogel is 60% by mass from the viewpoint of maintaining the shape of the hydrogel well and improving the dryness and stickiness of the hydrogel well. Above, preferably at least 70% by mass, and at most 97% by mass, preferably at most 95% by mass. Based on the above viewpoints, in the hydrogel of the present invention, the content of component (D) water is not less than 60% by mass and not more than 97% by mass, preferably not less than 70% by mass and not more than 95% by mass.

In addition, in the hydrogel of the present invention, water may be specially added water, or water contained in other raw materials (for example, water incidental to components (A) to (C)).

[other ingredients] The hydrogel of the present invention may still contain polyhydric alcohols with a molecular weight of 50-380.

From the viewpoint of having little effect on the viscosity of the hydrogel, an alcohol whose main chain is an alkyl group is preferred, a dihydric alcohol is more preferred, and a dihydric alcohol whose main chain has non-adjacent hydroxyl structures is even more preferred.

Examples of polyhydric alcohols having a molecular weight of 50 to 380 include: 1,2-propanediol, 1,3-propanediol, glycerin, 1,3-butanediol, 1,4-butanediol, dipropylene glycol, seaweed sugar etc. Among these, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1 , 1 or more of 2-propanediol, glycerin, and trehalose, more preferably 1 or more of 1,3-propanediol, 1,3-butanediol, and 1,4-butanediol .

From the viewpoint of the stability of the hydrogel, the content of the above-mentioned polyhydric alcohol in the total composition is 0.1% by mass or more, preferably 2% by mass or more, more preferably 5% by mass or more, and 27% by mass or less, Preferably it is 20 mass % or less, More preferably, it is 16.5 mass % or less, More preferably, it is 10 mass % or less, More preferably, it is 8 mass % or less.

In addition, in the hydrogel of the present invention, in addition to the above-mentioned components, components commonly used in cosmetics, such as moisturizing agents, whitening agents, blood circulation promoters, anti-inflammatory agents, Fungicides, UV absorbers, colorants, preservatives, antioxidants, fragrances, pH adjusters, chelating agents, etc.

＜Preparation method of hydrogel＞ The method for producing the hydrogel of the present invention can be, for example, the method of mixing component (A), component (C) and component (D) together to form an aqueous solution, dissolving component (B) in component (D) and An aqueous solution is formed, and then the aqueous solution of component (B) is added to the aqueous solutions of components (A) and (C), stirred, and left to obtain a hydrogel.

The preferred viscosity of the hydrogel of the present invention with undefined viscosity at room temperature (25° C.) is above 500 Pa‧s and below 8000 Pa‧s.

Even when the hydrogel of the present invention is filled into a portable package such as a tube or a bag, it is easy to take out without remaining in the package.

The hydrogel of the present invention is used by sticking to the skin, preferably to any part of the face, body, hands and feet other than the scalp. It can be stretched and extended at will during use, has a good fit to the skin, and brings good moisturizing properties to the user without stickiness and dryness, and is easy to peel off from the skin after use.

＜How to use hydrogel＞ In any case, the hydrogel of the present invention can be applied to the skin as an external preparation for skin, thereby achieving skin care. Specifically, when in use, the hydrogel can be stretched to an appropriate size first, and then attached to the skin; or, the hydrogel can be attached to the skin first and then extended to an appropriate size, and then kept on the skin Keep it for a period of time, preferably for 1 minute to 2 hours, more preferably for 5 minutes to 1 hour, and peel off easily after use, so as to obtain a good skin care effect. In addition, when using hydrogel, it can be combined with massage. Massage can be done directly with hands, or with tools such as sponges.

Furthermore, the present invention provides a method of moisturizing the skin by applying the hydrogel of the present invention to the skin to moisturize the skin.

Regarding the above-mentioned implementation manners, preferred implementation manners of the present invention are further disclosed below.

<1> A hydrogel containing the following components (A), (B), (C) and (D): (A) anionic polymers; (B) Trivalent metal salts and/or borates; (C) nonionic surfactants with an IOB value of 0.1 or more and 2 or less; and (D) water.

<2> The hydrogel according to <1>, wherein, Component (A) is one or more selected from the following components (A1), (A2), and (A3), (A1) anionic polyvinyl alcohol; (A2) an acrylic copolymer obtained by polymerizing at least one monomer selected from acrylic acid, methacrylic acid, and alkyl (meth)acrylates with alkyl carbon atoms of 1 to 30; (A3) Carboxymethylcellulose.

<3> The hydrogel as described in <2>, wherein the viscosity of a 4% aqueous solution of component (A1) anionic polyvinyl alcohol at 20°C is preferably at least 10 mPa‧s, more preferably at least 20 mPa‧s, and More preferably 25 mPa‧s or more; and, preferably less than 50 mPa‧s, more preferably less than 40 mPa‧s, more preferably less than 35 mPa‧s; furthermore, preferably 10~50 mPa‧s , more preferably 20~40 mPa‧s, more preferably 25~35 mPa‧s.

<4> The hydrogel according to <2> or <3>, wherein the content of the component (A1) in the hydrogel is not less than 5% by mass and not more than 20% by mass, preferably not more than 12% by mass ; Furthermore, in the hydrogel, the content of component (A1) is not less than 5% by mass and not more than 20% by mass, preferably not less than 8% by mass and not more than 12% by mass.

<5> The hydrogel according to any one of <2> to <4>, wherein the component (A2) is selected from polyacrylic acid and sodium polyacrylate, carbomer, methyl (meth)acrylate, (meth)acrylate, One or more of ethyl acrylate, butyl (meth)acrylate, and C10-30 alkyl acrylate.

<6> The hydrogel according to any one of <2> to <5>, wherein the content of the component (A2) in the hydrogel is not less than 0.1 mass % and not more than 20 mass %, preferably 15% by mass or less; Furthermore, in the hydrogel, the content of component (A2) is not less than 0.1% by mass and not more than 20% by mass, preferably not less than 0.1% by mass and not more than 15% by mass.

<7> The hydrogel according to any one of <2> to <6>, wherein the viscosity of a 1% aqueous solution of component (A3) carboxymethylcellulose at 20°C is 200 mPa‧s or more, and preferably It is 5000mPa‧s or less, more preferably 200~5000mPa‧s.

<8> The hydrogel according to any one of <2> to <7>, wherein the content of the component (A3) in the hydrogel is not less than 0.2 mass % and not more than 20 mass %, preferably 15% by mass or less; Furthermore, in the hydrogel, the content of component (A3) is not less than 0.2% by mass and not more than 20% by mass, preferably not less than 0.5% by mass and not more than 15% by mass.

<9> The hydrogel according to any one of <1> to <8>, wherein the total content of the components (A) in the hydrogel is 0.1% by mass or more, preferably 0.5% by mass or more, and 30% by mass or less, preferably 20% by mass or less; further, the total content of components (A) is 0.1% by mass to 30% by mass, preferably 0.5% by mass to 20% by mass.

<10> The hydrogel according to any one of <1> to <9>, wherein the component (B) is selected from iron salts containing iron ions (Fe ³⁺ ), iron salts containing manganese ions (Mn ³⁺ ). One or more of manganese salts, chromium salts containing chromium ions (Cr ³⁺ ), and aluminum salts containing aluminum ions (Al ³⁺ ); component (B) is preferably selected from aluminum salts and/or boric acid Salt; Component (B) is more preferably selected from aluminum chloride, potassium alum, ammonium alum, aluminum acetate, aluminum magnesium methyl silicate, aluminum magnesium silicate, aluminum magnesium metasilicate, EDTA‧aluminum, aluminum allantoin , aluminum hydroxide, aluminum magnesium hydroxide, p-hydroxyaluminum acetic acid, aluminum sulfate, potassium aluminum sulfate, aluminum lactate, aluminum glycolate, aluminum glycinate, aluminum oxide, aluminum borate, sodium tetraborate, potassium tetraborate, One or more of ammonium tetraborate, sodium pentaborate, potassium pentaborate, and ammonium pentaborate.

<11> The hydrogel according to any one of <1> to <10>, wherein the content of the component (B) in the hydrogel is 0.2% by mass or more in terms of sodium borate, and is 3% by mass or less; Furthermore, in the hydrogel, the content of the component (B) is 0.2% by mass or more and 3% by mass or less in terms of sodium borate conversion.

<12> The hydrogel according to any one of <1> to <11>, wherein the ratio of the molar amount of the trivalent metal ion in the component (B) to the molar amount of the anion group in the component (A) is 0.5 to 10 , preferably 3~6; the mass ratio of (B) to (A) is 0.001~0.5, preferably 0.01~0.06.

<13> The hydrogel according to any one of <1> to <12>, wherein the component (C) is a nonionic surfactant having an IOB value of 0.1 to 2, preferably selected from PEG fatty acid esters , PEG hydrogenated castor oil, PEG fatty acid glycerides, PPG glucosinolates, PPG polyglyceryl ethers, polyglyceryl fatty acid esters, PEG polydimethylsiloxane, sorbitan fatty acid esters, PEG sorbitan One or more of fatty acid esters, fatty alcohol polyethers, and glucosides.

<14> The hydrogel according to any one of <1> to <13>, wherein the component (C) nonionic surfactant has an IOB value of preferably 1 to 1.5, more preferably 1.16 to 1.37.

<15> The hydrogel according to any one of <1> to <14>, wherein the content of the component (C) in the hydrogel is 2.0% by mass or more, preferably 3.0% by mass or more, and is 10.0% by mass. Mass % or less, preferably 5.0 mass % or less; Furthermore, in the hydrogel, the content of component (C) is 2.0 mass % or more and 10.0 mass % or less, preferably 2.0 mass % or more and 5.0 mass % or less, more Preferably, it is not less than 2.0% by mass and not more than 4.0% by mass.

<16> The hydrogel according to any one of <1> to <15>, wherein the mass ratio (C)/(A) of component (C) to component (A) is 0.15 to 2.0, preferably 0.15~0.5.

<17> The hydrogel according to any one of <1> to <16>, wherein the water content of component (D) in the hydrogel is 60% by mass or more, preferably 70% by mass or more, and is 97 mass % or less, preferably 95 mass % or less; further, in the hydrogel, the content of component (D) water is 60 mass % or more and 97 mass % or less, preferably 70 mass % or more and 95 mass % the following.

<18> The hydrogel according to any one of <1> to <17>, wherein the viscosity of the hydrogel at room temperature (25°C) is preferably 500 Pa‧s or more and 8000 Pa‧s the following.

<19> Use of the hydrogel according to any one of <1> to <18> as an external preparation for skin.

<20> A skin care method comprising applying the hydrogel according to any one of <1> to <18> to the skin to care for the skin.

<21> A method of moisturizing the skin, comprising applying the hydrogel according to any one of <1> to <18> to the skin to moisturize the skin. [Example]

Hereinafter, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to a following example. In addition, the quantity of each component is mass %.

1. Manufacturing method According to the compositions shown in Tables 1 to 3 (the values shown in Table 1 are the content of active ingredients), components (A), (C) and optional components other than (A) are dispersed in a deionized water, and stir it in a water bath above 80°C to dissolve it completely. After cooling it to room temperature, make up the evaporated water content, then add the aqueous solution of component (B), and manually stir the obtained mixture to make the component (A) A gelation reaction occurs with the component (B), and after standing still, the mixture is stirred again to obtain a hydrogel.

2. Evaluation of sense of use (1) Evaluation of dryness improvement effect A sensory evaluation method was used. Take 2g each of the sample without non-ionic surfactant in the control group and the comparison sample with non-ionic surfactant added in the examples and comparative examples of the present invention, rub it with your fingers and feel the difference between the samples. The difference in the sense of dryness was evaluated according to the following scoring criteria. There were 10 subjects, each of whom evaluated the sense of dryness of the samples in the control group and the samples in the examples and comparative examples of the present invention, and scored them. Finally take the average of 10 scores. 3 points: Compared with the control group, the control sample has improved. 2 points: Compared with the control group, the comparison sample is slightly improved. 1 point: no improvement in the control sample compared to the control group.

(2) Evaluation of sticky feeling improvement effect A sensory evaluation method was used. Take 2g each of the sample without non-ionic surfactant in the control group and the comparison sample with non-ionic surfactant added in the examples and comparative examples of the present invention, press with your fingers and feel the difference between the samples. The difference in stickiness was evaluated according to the following scoring criteria. There were 10 subjects, each of whom evaluated the stickiness of the samples in the control group and the samples in the examples and comparative examples of the present invention, and scored them. Finally take the average of 10 scores. 3 points: Compared with the control group, the control sample has improved. 2 points: Compared with the control group, the comparison sample is slightly improved. 1 point: no improvement in the control sample compared to the control group.

Table 1 Composition (mass%) Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative example 1 Comparative example 2 A A1 Polyvinyl alcohol (T330H) 10.7 10.7 10.7 10.7 10.7 10.7 10.7 10.7 B B1 Aluminum chloride (active ingredient content: 10%) 3.27 3.27 3.27 3.27 3.27 3.27 3.27 3.27 B2 Aluminum sulfate (active ingredient content: 6%) 1.13 1.13 1.13 1.13 1.13 1.13 1.13 1.13 nonionic surfactant (C) PPG-9 diglyceryl ether 2.0 PPG-10 Methyl Glucose Ether 2.0 PEG-7 Glyceryl Cocoate 2.0 PEG-6 Caprylic/Capric Glycerides 2.0 PEG-60 castor oil 1.3 PEG-12 Laurate 2.0 (C') Methyl Gluceth-20 2.0 Methyl Gluceth-10 2.0 IOB value of component (C) or component (C') 0.90 0.95 1.16 1.25 1.36 1.37 2.07 2.22 (D) water The remaining amount The remaining amount The remaining amount The remaining amount The remaining amount The remaining amount The remaining amount The remaining amount B/A(mol/mol)* 5.0 5.0 5.0 5.0 5.0 5.0 5.0 5.0 B/A (mass%/mass%) 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 other ingredients PG 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 1,3-BG 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 MP 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Feeling of use evaluation Stickiness improvement effect 3 3 3 3 3 3 3 3 Dryness improvement effect 2 2 3 3 2 3 1 1 *: Here, B/A is the molar ratio of Al ³⁺ /carboxyl group.

Table 2 Composition (mass%) Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Example 13 Comparative example 3 Comparative example 4 A A1 Polyvinyl alcohol (T330H) 5.0 8.56 10.7 10.7 10.7 15 20 5.0 10.7 B B1 Aluminum chloride (active ingredient content: 10%) 0.9 1.56 3.27 3.27 3.27 4.3 5.5 0.9 3.27 B2 Aluminum sulfate (active ingredient content: 6%) 0.35 0.6 1.13 1.13 1.13 4.7 9.5 0.35 1.13 C C1 PEG-6 Caprylic/Capric Glycerides 1.7 0.67 0.67 0.5 0.33 0.5 0.67 2.5 0.17 C2 PEG-12 Laurate 8.3 3.33 3.33 2.5 1.67 2.5 3.33 12.5 0.83 IOB value of component (C) or component (C') 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 1.35 (C) total content 10 4.0 4.0 3.0 2.00 3.0 4.0 15 1.00 (D) water The remaining amount The remaining amount The remaining amount The remaining amount The remaining amount The remaining amount The remaining amount The remaining amount The remaining amount other ingredients PG 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 4.8 1,3-BG 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 2.4 MP 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 C/A 2 0.47 0.37 0.28 0.18 0.2 0.2 3 0.09 B/A(mol/mol)* 3.0 3.0 5.0 5.0 5.0 6.0 7.0 3.0 5.0 B/A (mass%/mass%) 0.02 0.02 0.04 0.04 0.04 0.05 0.06 0.02 0.04 Feeling of use evaluation Stickiness improvement effect 3 3 3 3 3 2 2 layered 3 Dryness improvement effect 3 3 3 3 3 3 3 layered 1 *: Here, B/A is the molar ratio of Al ³⁺ /carboxyl group.

table 3 Composition (mass%) Example 14 Example 15 Example 16 Example 17 A A1 Polyvinyl alcohol (T330H) 9.63 9.63 9.63 9.63 B B1 Aluminum chloride (active ingredient content: 10%) 3.27 2.7 2.12 1.51 B2 Aluminum sulfate (active ingredient content: 6%) 1.13 0.82 0.64 0.45 C C1 PEG-6 Caprylic/Capric Glycerides 0.5 0.5 0.5 0.5 C2 PEG-12 Laurate 2.5 2.5 2.5 2.5 IOB value of component (C) or component (C') 1.35 1.35 1.35 1.35 (C) total content 3.0 3.0 3.0 3.0 (D) water margin margin margin margin other ingredients PG 4.8 4.8 4.8 4.8 1,3-BG 2.4 2.4 2.4 2.4 MP 0.2 0.2 0.2 0.2 C/A 0.31 0.31 0.31 0.31 B/A(mol/mol)* 5.5 4.5 3.5 2.5 B/A (mass%/mass%) 0.04 0.03 0.03 0.01 Feeling of use evaluation Stickiness improvement effect 3 3 3 3 Dryness improvement effect 3 3 3 3 *: Here, B/A is the molar ratio of Al ³⁺ /carboxyl group.

From Table 1 to Table 3, it can be seen that the hydrogel of the present invention has excellent non-sticky and dry feeling, and can achieve good touch and use feeling.

(Note) The components described in Table 1 to Table 3 are the following substances. Polyvinyl alcohol: GOHSENX T-330H (active ingredient content: 96%), manufactured by Mitsubishi Chemical Corporation. Aluminum Chloride: Manufactured by Sinopharm Chemical Reagent Co., Ltd. Aluminum sulfate: manufactured by Sinopharm Chemical Reagent Co., Ltd. Aluminum glycinate: manufactured by Sinopharm Chemical Reagent Co., Ltd. Borax: Manufactured by Jianrong Pharmaceutical Co., Ltd. PPG-9 diglyceryl ether: trade name SY-DP9 (active ingredient content: 100%), manufactured by Sakamoto Yakuhin Kogyo Co., Ltd. PPG-10 Methyl Glucose Ether: trade name MACBIO BRIDE MG-10P (active ingredient content: 100%), manufactured by NOF CORPORATION. PEG-7 glyceryl cocoate: trade name CETIOL HE (active ingredient content: 100%), manufactured by BASF SE. PEG-6 caprylic/capric glyceride: trade name TEGOSOFT GMC 6 (active ingredient content: 100%), manufactured by Evonik Operations GmbH. PEG-60 castor oil: trade name NIKKOL HCO-60 (active ingredient content: 100%), manufactured by Nippon Surfactant Industries Co., Ltd. PEG-12 laurate: trade name EMANON 1112 (active ingredient content: 100%), manufactured by Kao Corporation. Methylgluceth-20: trade name MACBIO BRIDE MG-20E (active ingredient content: 100%), manufactured by NOF CORPORATION. Methylgluceth-10: trade name MACBIO BRIDE MG-10E (active ingredient content: 100%), manufactured by NOF CORPORATION. PROPYLENE GLYCOL (JSQI): Propylene glycol, trade name (active ingredient content: 100%), manufactured by AGC Inc. 1,3-BUTYLENE GLYCOL-P: 1,3-Butanediol, trade name (active ingredient content: 100%), manufactured by KH NeoChem Co., Ltd. MEKKINS-M (UENO METHYL PARABEN NF): methylparaben, trade name (active ingredient content: 100%), manufactured by Ueno Fine Chemicals Industry, Ltd.

The formulation examples of the hydrogel of the present invention are listed below. It should be noted that the present invention is not limited by these formulation examples. The hydrogels in the formulation examples have no sticky or dry feeling, and exhibit a good touch and use feeling.

Formulation Example 1: Polyvinyl alcohol (T330H) 11.2% by mass Aluminum glycinate 0.345% by mass PEG-6 caprylic/capric glycerides 0.33% by mass PEG-12 laurate 1.67% by mass. Formulation Example 2: Polyvinyl alcohol (T330H) 11% by mass Borax 10% by mass PEG-6 caprylic/capric glycerides 0.33% by mass PEG-12 laurate 1.67% by mass.

Claims (11)

A hydrogel comprising the following components (A), (B), (C) and (D): (A) anionic polymers; (B) Trivalent metal salts and/or borates; (C) nonionic surfactants with an IOB value of 0.1 or more and 2 or less; and (D) water. The hydrogel according to claim 1, wherein component (A) is one or more selected from the following components (A1), (A2), and (A3): (A1) anionic polyvinyl alcohol; (A2) an acrylic copolymer obtained by polymerizing at least one monomer selected from acrylic acid, methacrylic acid, and alkyl (meth)acrylates with alkyl carbon atoms of 1 to 30; (A3) Carboxymethylcellulose. The hydrogel according to claim 1 or 2, wherein component (B) is selected from aluminum salts and/or borates. The hydrogel according to any one of claims 1 to 3, wherein component (C) is selected from PEG fatty acid esters, PEG hydrogenated castor oil, PEG fatty acid glycerides, PPG glucopolyether, PPG polyglyceryl ether, Polyglyceryl fatty acid ester, PEG dimethicone, sorbitan fatty acid ester, PEG sorbitan fatty acid ester, fatty alcohol polyether, glucoside, one or more nonionic interfaces active agent. The hydrogel according to any one of claims 1 to 4, wherein the mass ratio (C)/(A) of component (C) to component (A) is 0.15~2. The hydrogel according to any one of claims 1 to 5, wherein the content of component (A) in the hydrogel is 5 to 20% by mass. The hydrogel according to any one of claims 1 to 6, wherein the content of component (B) in the hydrogel is 0.2 to 3% by mass. The hydrogel according to any one of claims 1 to 7, wherein the content of component (C) in the hydrogel is 2 to 10% by mass. The hydrogel according to any one of claims 1 to 8, wherein the content of component (D) in the hydrogel is 60-93% by mass. A use of a hydrogel as an external skin preparation, the hydrogel is the hydrogel according to any one of claims 1 to 9. A skin care method, which is to apply the hydrogel according to any one of claims 1 to 9 to the skin.