Gel Composition

Abstract

The present invention pertains to: [1] an aluminum-ion-containing gel composition, the gel composition being such that when a dynamic viscoelasticity measurement (frequency dependent) is carried out on the gel composition with the strain condition in the linear region and at 25°C, a frequency at which the loss modulus G'' / storage modulus G' (tan δ) is 1 is present in the frequency range of 0.001-100 rad / s, and the storage modulus G' of the gel composition at 25° and a frequency of 62.8 rad / s is 500 Pa or above; and [2] a skin topical agent containing the gel composition.

Description

[Technical Field]

[0001] The present invention relates to a gel composition and an external preparation for skin. [Background technology]

[0002] Gel compositions are widely used in various fields, such as pharmaceuticals, quasi-drugs, cosmetics, fragrances, paints, adhesives, binders, packaging materials, emulsifiers, suspending agents, water retention agents, surfactants, fiber treatment agents, and paper processing agents. Techniques relating to gel compositions include those described in Patent Documents 1 and 2 below.

[0003] Japanese Patent Application Laid-Open No. 55-127311 (Patent Document 1) describes a pack cosmetic characterized by combining a first agent, a sol of a divalent metal lactate or chloride added to an aqueous polyvinyl alcohol solution, and a second agent, a sol of an aqueous solution of alginic acid sodium salt, potassium salt, or triethanolamine salt added to borax, to form a gel film of both the first and second agents.The pack cosmetic shows almost no change over time even when applied to the skin for long periods of time, the peeling time can be freely changed, and it is able to maintain a state of constantly absorbing moisture, making it an extremely effective pack cosmetic in terms of the physiological functions and cosmetic effects of the skin.

[0004] Japanese Patent Application Laid-Open No. 2020-152869 (Patent Document 2) describes that a polyvinyl alcohol-based gel molding having a structure in which a polyvinyl alcohol-based polymer is crosslinked with a titanium chelate compound has excellent strength. The polyvinyl alcohol-based gel moldings of Patent Document 2 are primarily intended for use as carriers for fixing microorganisms, water-retaining materials, cold insulators, filtering materials, etc., and are not intended for use in the fields of cosmetics, perfumes, toiletries, pharmaceuticals, quasi-drugs, etc., or as gel-type skin care agents.

[0005] Furthermore, as a technique relating to a composition containing polyvinyl alcohol, there is, for example, the technique described in Japanese Patent Application Laid-Open No. 11-1595 (Patent Document 3). Patent Document 3 describes that an aqueous composition consisting of (A) a modified polyvinyl alcohol containing 0.1 to 20 mol% of carboxy groups in the molecule and (B) a water-soluble aluminum compound, in which the solid content ratio (A) / (B) by weight is 100 / 0.01 to 100 / 50, exhibits a large increase in viscosity with evaporation of water and has remarkably excellent initial adhesive strength. The aqueous composition of Patent Document 3 is primarily intended for use as a paper processing adhesive, woodworking adhesive, fiber treatment agent, binder, paint, etc., which are solidified by evaporating water, and is not intended for use in the fields of cosmetics, perfumes, toiletries, pharmaceuticals, quasi-drugs, etc., or as a gel-type skin care agent. Summary of the Invention

[0006] The present invention provides a gel composition comprising aluminum ions, When the dynamic viscoelasticity measurement (frequency dependency) was performed on the gel composition at 25°C under strain conditions within the linear region, In the frequency range of 0.001 to 100 rad / s, there exists a frequency where the loss modulus G'' / storage modulus G' (tanδ) is 1. The gel composition has a storage modulus G' of 500 Pa or more at 25°C and a frequency of 62.8 rad / s. DETAILED DESCRIPTION OF THE INVENTION

[0007] Mask products such as skin care masks include, for example, sheet masks made of nonwoven fabric impregnated with liquid. However, such sheet masks have insufficient adhesion and stretchability to the skin, resulting in poor fitting to the skin. Here, the gel compositions described in Patent Documents 1 and 2 and the polyvinyl alcohol-based material described in Patent Document 3 have not been examined in terms of adhesion and stretchability to the skin. The present invention relates to a gel composition and an external preparation for skin that have an improved balance of adhesion and extensibility.

[0008] The present inventors have discovered that a gel composition containing aluminum ions, which has a frequency at which the loss modulus G'' / storage modulus G' is 1 and has a storage modulus G' at a specific frequency within a specific range, can improve the balance between adhesion and extensibility, and have completed the present invention.

[0009] That is, the present invention relates to the following [1] and [2]. [1] A gel composition containing aluminum ions, When the dynamic viscoelasticity measurement (frequency dependency) was performed on the gel composition at 25°C under strain conditions within the linear region, In the frequency range of 0.001 to 100 rad / s, there exists a frequency where the loss modulus G'' / storage modulus G' (tanδ) is 1. A gel composition having a storage modulus G' of 500 Pa or more at 25°C and a frequency of 62.8 rad / s. [2] A topical skin preparation comprising the gel composition described in [1] above.

[0010] According to the present invention, it is possible to provide a gel composition and an external preparation for skin that have an improved balance between adhesion and extensibility.

[0011] [Gel composition] The gel composition of the present invention is a gel composition containing aluminum ions, and when dynamic viscoelasticity measurement (frequency dependence) is performed on the gel composition at 25°C under strain conditions within a linear region, there is a frequency in the frequency range of 0.001 to 100 rad / s where the ratio of loss modulus G'' / storage modulus G' (tan δ) is 1, and the storage modulus G' of the gel composition at 25°C and a frequency of 62.8 rad / s is 500 Pa or more. In the present invention, "comprising component X" is considered to be synonymous with "composed of component X."

[0012] The gel composition of the present invention can improve the balance between adhesion and extensibility. The gel composition of the present invention has good adhesion to the skin, so it is preferably applied to the skin. Therefore, the gel composition of the present invention has particularly good fitting properties to the skin and can be suitably used as an external skin preparation. The external skin preparation of the present invention means a composition applied to the skin in the fields of cosmetics, perfumes, cosmetics, pharmaceuticals, quasi-drugs, etc.

[0013] The reason why the gel composition of the present invention has the above-described structure and thereby exhibits the effects of the present invention is not clear, but is presumed to be as follows. The gel composition of the present invention contains aluminum ions, and has a frequency in the frequency range of 0.001 to 100 rad / s where the ratio of loss modulus G'' / storage modulus G' (tan δ) is 1, and has a storage modulus G' of 500 Pa or more at 25°C and a frequency of 62.8 rad / s. The aluminum ions are capable of forming a cross-linked gel through ionic interactions. If there is a frequency in the frequency range of 0.001 to 100 rad / s where the loss modulus G'' / storage modulus G' (tan δ) is 1, the gel composition will have the unique property that the low frequency side, i.e., long-term movement, has stronger viscous properties, and the high frequency side, i.e., short-term movement, has stronger elastic properties. When the gel composition has such properties, it has a moderate softness and is easy to spread, and if the storage modulus G' is 500 Pa or higher, the gel composition has a moderate hardness and is less likely to flow. A gel composition having such unique properties is highly viscous, which is believed to improve the extensibility of the gel composition of the present invention. Furthermore, when the gel composition is in close contact with an object, the gel composition is less likely to flow due to its adhesive strength and appropriate elastic modulus. These properties are believed to improve the adhesion of the gel composition of the present invention.

[0014] <Component (A)> The gel composition of the present invention preferably contains a polymer as component (A), which polymer forms the skeleton of the gel composition. Component (A) is, for example, an anionic polymer, preferably an anionic polymer having an anionic group such as a sulfonic acid group, a sulfate group, a carboxy group, a phosphate group, or a phosphonate group, more preferably an anionic polymer having at least one anionic group selected from sulfonic acid groups and carboxy groups, and even more preferably an anionic polymer having a carboxy group. Examples of anionic polymers include vinyl polymers having anionic groups, such as anionic polyvinyl alcohol, carboxyvinyl polymers, and (meth)acrylic acid / (meth)acrylic acid ester copolymers; and anionic polysaccharides, such as anionic cellulose. From the viewpoint of further improving the balance between adhesion and extensibility, component (A) is preferably an anionized polyvinyl alcohol, more preferably a polyvinyl alcohol having at least one anionic group selected from a sulfonic acid group and a carboxy group, and even more preferably a polyvinyl alcohol having a carboxy group. In this specification, the term "anionic group" refers to an anionic group or a group that can be ionized to become an anionic group.

[0015] Examples of polyvinyl alcohols having a carboxy group include: (1) those obtained by graft polymerization or block polymerization of polyvinyl alcohol with an unsaturated monomer having a carboxy group; (2) those obtained by copolymerizing a vinyl ester compound with an unsaturated monomer having at least one selected from a carboxy group and a carboxylic acid ester group, followed by saponification; (3) those obtained by polymerizing a vinyl ester compound using a chain transfer agent having a carboxy group, followed by saponification; and (4) those obtained by reacting polyvinyl alcohol with a carboxylating agent.

[0016] Examples of the unsaturated monomer having a carboxyl group used in the above methods (1) and (2) and the unsaturated monomer having a carboxylic acid ester group used in the method (2) include ethylenically unsaturated dicarboxylic acids such as maleic acid, fumaric acid, itaconic acid, etc.; ethylenically unsaturated dicarboxylic acid monoesters such as maleic acid monoalkyl esters, fumaric acid monoalkyl esters, itaconic acid monoalkyl esters, etc.; ethylenically unsaturated dicarboxylic acid diesters such as maleic acid dialkyl esters, fumaric acid dialkyl esters, itaconic acid dialkyl esters, etc.; 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 (meth)acrylic acid alkyl esters, etc. Furthermore, salts of the above compounds may be used as the unsaturated monomer having at least one selected from the group consisting of a carboxyl group and a carboxylic acid ester group. These compounds may be used alone or in combination of two or more.

[0017] Examples of vinyl ester compounds used in the above methods (2) and (3) include vinyl acetate, vinyl formate, vinyl propionate, vinyl versatate, vinyl pivalate, etc. Among these, vinyl acetate is preferred from the viewpoints of reactivity during synthesis and easy availability. These compounds may be used alone or in combination of two or more.

[0018] Examples of the carboxylating agent used in the above method (4) include carboxylic acid anhydrides such as succinic anhydride, maleic anhydride, acetic anhydride, trimellitic anhydride, phthalic anhydride, pyromellitic anhydride, glutaric anhydride, hydrogenated phthalic anhydride, and naphthalenedicarboxylic anhydride. These may be used alone or in combination of two or more.

[0019] The amount of anionic groups in the anionized polyvinyl alcohol (the proportion derived from monomers having anionic groups) is preferably 0.1 mol % or more, more preferably 0.5 mol % or more, and even more preferably 1 mol % or more, from the viewpoint of further improving adhesion and improving water retention and gel strength, and is preferably 10 mol % or less, more preferably 5 mol % or less, and even more preferably 3 mol % or less, from the viewpoint of further improving the balance between adhesion and extensibility and improving the amount of water supplied and the moisturizing feeling when applied to the skin. The amount of anionic groups in the anionic polyvinyl alcohol is determined by dividing the anionic polyvinyl alcohol before saponification by: 1 It can be determined by analysis using H-NMR (solvent: CDCl3).

[0020] The saponification degree of the anionized polyvinyl alcohol is, from the viewpoint of further improving adhesion and improving water retention and gel strength, 90 mol% or more, more preferably 95 mol% or more, and even more preferably 98 mol% or more. The upper limit of the saponification degree is not particularly limited, but is, for example, 100.0 mol% or less, preferably 99.9 mol% or less, and more preferably 99.5 mol% or less. The degree of saponification of the anionized polyvinyl alcohol is measured in accordance with JIS K6726:1994.

[0021] The degree of polymerization of the anionized polyvinyl alcohol is preferably 100 or more, more preferably 500 or more, and even more preferably 1,000 or more, from the viewpoint of further improving the balance between adhesion and extensibility, and from the viewpoint of improving water retention and gel strength, and is preferably 200,000 or less, more preferably 10,000 or less, and even more preferably 4,000 or less, from the viewpoint of further improving the balance between adhesion and extensibility. The degree of polymerization of anionized polyvinyl alcohol can be calculated from the relative viscosity of an aqueous solution of completely saponified polyvinyl alcohol to water (see JIS K6726:1994).

[0022] Specific examples of anionic polyvinyl alcohols include KL-118, KL-318, KL-506, KM-118, and KM-618 manufactured by Kuraray Co., Ltd.; Gohsenex CKS50, Gohsenex T-330H, Gohsenex T-330, and Gohsenex T-350 manufactured by Mitsubishi Chemical Corporation; and AP-17, AT-17, and AF-17 manufactured by Nippon Vaccination & Poval Co., Ltd.

[0023] The component (A) may be used alone or in combination of two or more types.

[0024] The content of component (A) in the gel composition of the present invention is preferably 1.0% by mass or more, more preferably 3.0% by mass or more, even more preferably 5.0% by mass or more, and even more preferably 8.0% by mass or more, from the viewpoint of further improving the balance between adhesion and extensibility, and from the viewpoint of improving water retention and gel strength, and is preferably 30.0% by mass or less, more preferably 25.0% by mass or less, even more preferably 20.0% by mass or less, even more preferably 15.0% by mass or less, even more preferably 13.0% by mass or less, even more preferably 12.5% by mass or less, and even more preferably 12.0% by mass or less, from the viewpoint of further improving the balance between adhesion and extensibility.

[0025] <Component (B): Aluminum ion> The gel composition of the present invention contains aluminum ions as component (B). The source of the aluminum ions is preferably aluminum salt (B'). That is, the gel composition of the present invention preferably contains aluminum salt (B'). The aluminum salt (B') is preferably water-soluble, and examples thereof include salts of aluminum with an inorganic acid selected from hydrochloric acid, nitric acid, sulfuric acid, etc., or an organic acid such as acetic acid. Specific examples of the aluminum salt (B') include aluminum chloride, aluminum nitrate, aluminum sulfate, aluminum potassium sulfate, etc. Among these, from the viewpoints of safety, availability, price, gel properties, etc., at least one selected from aluminum chloride, aluminum sulfate, and aluminum potassium sulfate is preferred, and at least one selected from aluminum chloride and aluminum sulfate is more preferred.

[0026] The aluminum salt (B') may be used alone or in combination of two or more kinds.

[0027] The content of the aluminum salt (B') in the gel composition of the present invention is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.10% by mass or more, even more preferably 0.20% by mass or more, even more preferably 0.23% by mass or more, and even more preferably 0.25% by mass or more, from the viewpoint of further improving the balance between adhesion and extensibility, and from the viewpoint of improving the water retention ability and gel strength, and is preferably 10.0% by mass or less, more preferably 5.0% by mass or less, even more preferably 2.0% by mass or less, even more preferably 1.0% by mass or less, even more preferably 0.80% by mass or less, even more preferably 0.60% by mass or less, even more preferably 0.50% by mass or less, even more preferably 0.40% by mass or less, even more preferably 0.36% by mass or less, and even more preferably 0.34% by mass or less, from the viewpoint of further improving the balance between adhesion and extensibility.

[0028] <Water> The gel composition of the present invention preferably contains water as component (C). Examples of the water component (C) include deionized water, distilled water, highly purified water, and ultrapure water.

[0029] The content of component (C) in the gel composition of the present invention is preferably the amount remaining after excluding component (A), aluminum salt (B'), and other components described below. The content of component (C) in the gel composition of the present invention is preferably 65.0% by mass or more, more preferably 70.0% by mass or more, even more preferably 75.0% by mass or more, even more preferably 78.0% by mass or more, even more preferably 80.0% by mass or more, and even more preferably 83.0% by mass or more, from the viewpoints of adjusting the viscosity of the gel composition to an appropriate level and improving the stability of the gel composition and the moisturizing feeling when applied to the skin, and from the similar viewpoints, is preferably 98.99% by mass or less, more preferably 98.0% by mass or less, even more preferably 96.0% by mass or less, and even more preferably 94.0% by mass or less.

[0030] <Ratio of each ingredient> In the gel composition of the present invention, the mass ratio of component (C) to component (A) ((C) / (A)) is preferably 1.0 or more, more preferably 2.0 or more, even more preferably 3.0 or more, and even more preferably 4.0 or more, from the viewpoint of further improving the balance between adhesion and extensibility, and from the viewpoint of improving the amount of water supplied and the moisturizing feeling when applied to the skin, and is preferably 20.0 or less, more preferably 16.0 or less, even more preferably 14.0 or less, even more preferably 12.0 or less, and even more preferably 11.0 or less, from the viewpoint of further improving the balance between adhesion and extensibility, and from the viewpoint of improving the water retention power and gel strength.

[0031] In the gel composition of the present invention, the mass ratio of the aluminum salt (B') to the component (A) ((B') / (A)) is preferably 0.001 or more, more preferably 0.005 or more, even more preferably 0.010 or more, even more preferably 0.020 or more, and even more preferably 0.025 or more, from the viewpoint of further improving the balance between adhesion and extensibility, and from the viewpoint of improving water retention and gel strength, and is preferably 0.500 or less, more preferably 0.200 or less, even more preferably 0.120 or less, even more preferably 0.080 or less, even more preferably 0.060 or less, and even more preferably 0.040 or less, from the viewpoint of further improving the balance between adhesion and extensibility.

[0032] <Sulfate ions> The gel composition of the present invention may further contain sulfate ions from the viewpoint of exhibiting preferable gel properties even after storage. The sulfate ion may be an ion derived from component (B'), or may be an ion derived from a sulfate salt other than component (B') or sulfuric acid. Examples of sulfate salts other than component (B') include sodium sulfate, potassium sulfate, magnesium sulfate, zinc sulfate, and iron sulfate. In the gel composition of the present invention, the molar ratio of sulfate ions to aluminum ions (SO4 2- / Al 3+ ) is preferably 0.08 or more, more preferably 0.09 or more, even more preferably 0.10 or more, even more preferably 0.11 or more, even more preferably 0.13 or more, and even more preferably 0.15 or more, from the viewpoint of adjusting the viscosity during storage, and is preferably 1.45 or less, more preferably 0.50 or less, even more preferably 0.45 or less, even more preferably 0.35 or less, even more preferably 0.27 or less, even more preferably 0.25 or less, even more preferably 0.23 or less, and even more preferably 0.20 or less, from the viewpoint of adjusting the viscosity during storage. Here, the aluminum ions are usually ions derived from component (B').

[0033] <Other ingredients> The gel composition of the present invention may contain other ingredients as appropriate within the scope of not impairing the object of the present invention. Examples of other ingredients include ingredients that are commonly used in cosmetics, perfumes, cosmetics, pharmaceuticals, quasi-drugs, etc. Ingredients commonly used in these products include, for example, polymers other than anionic polymers, moisturizers, whitening agents, blood circulation promoters, anti-inflammatory agents, disinfectants, UV absorbers, colorants, preservatives, antioxidants, fragrances, pH adjusters, chelating agents, humectants, medicines, alcohols, etc.

[0034] <ph> The pH of the gel composition of the present invention at 25°C is preferably 2.0 or higher, more preferably 2.5 or higher, even more preferably 2.8 or higher, and even more preferably 3.0 or higher, from the viewpoint of suppressing stickiness and improving water retention and gel strength, and is preferably 6.5 or lower, more preferably 6.0 or lower, even more preferably 5.5 or lower, and even more preferably 5.0 or lower, from the viewpoint of improving adhesion, flexibility and elongation, and improving the amount of water supplied and the moisturizing feeling when applied to the skin. The pH of the gel composition of the present invention at 25° C. can be measured specifically by the method described in the Examples.

[0035] <Dynamic viscoelasticity> From the viewpoint of further improving the balance between adhesion and extensibility, it is preferable that the gel composition of the present invention has a loss modulus G">storage modulus G' in a frequency region lower than the frequency at which tan δ becomes 1, and a storage modulus G'>loss modulus G" in a frequency region higher than the frequency at which tan δ becomes 1. In the present invention, as shown below, the storage modulus G' and loss modulus G" can be used at a frequency of 62.8 rad / s as the frequency region higher than the frequency at which tan δ becomes 1 for the gel composition at 25°C, and at a frequency of 0.135 rad / s as the frequency region lower than the frequency at which tan δ becomes 1 for the gel composition.

[0036] In the gel composition of the present invention, the frequency at which tan δ becomes 1 is preferably 0.1 rad / s or more, more preferably 1.0 rad / s or more, even more preferably 1.5 rad / s or more, and even more preferably 2.5 rad / s or more, from the viewpoint of further improving the balance between adhesion and extensibility, and from the same viewpoint, is preferably 30.0 rad / s or less, more preferably 20.0 rad / s or less, even more preferably 15.0 rad / s or less, even more preferably 10.0 rad / s or less, even more preferably 8.0 rad / s or less, and even more preferably 6.5 rad / s or less.

[0037] The storage modulus G' (25°C, frequency: 62.8 rad / s) of the gel composition of the present invention is, from the viewpoint of improving the balance between adhesion and extensibility, and from the viewpoint of improving water retention and gel strength, 500 Pa or more, preferably 700 Pa or more, more preferably 900 Pa or more, even more preferably 1,500 Pa or more, and even more preferably 1,800 Pa or more; from the viewpoint of further improving extensibility, it is preferably 15,000 Pa or less, more preferably 10,000 Pa or less, even more preferably 9,500 Pa or less, even more preferably 8,000 Pa or less, even more preferably 7,000 Pa or less, and even more preferably 6,500 Pa or less.

[0038] The ratio (G'' / G'(tan δ)) of the loss modulus G'' (25°C, frequency: 62.8 rad / s) to the storage modulus G' (25°C, frequency: 62.8 rad / s) of the gel composition of the present invention is preferably 0.10 or more, more preferably 0.15 or more, even more preferably 0.20 or more, and even more preferably 0.25 or more, from the viewpoint of further improving adhesion and further improving extensibility, and from the same viewpoints, is preferably 1.0 or less, more preferably 0.70 or less, even more preferably 0.50 or less, even more preferably 0.40 or less, and even more preferably 0.35 or less.

[0039] Furthermore, the ratio (G'' / G'(tan δ)) of the loss modulus G'' (25°C, frequency: 0.135 rad / s) to the storage modulus G' (25°C, frequency: 0.135 rad / s) of the gel composition of the present invention is, from the viewpoint of further improving adhesion and from the viewpoint of improving extensibility, preferably 0.10 or more, more preferably 0.50 or more, even more preferably 0.80 or more, even more preferably 1.0 or more, even more preferably 1.5 or more, and even more preferably 1.8 or more; and from the same viewpoints, it is preferably 10.0 or less, more preferably 5.0 or less, even more preferably 4.0 or less, even more preferably 3.5 or less, even more preferably 3.3 or less, and even more preferably 3.2 or less.

[0040] The storage modulus G' (25°C, frequency: 0.135 rad / s) of the gel composition of the present invention is preferably 1 Pa or more, more preferably 5 Pa or more, even more preferably 10 Pa or more, even more preferably 15 Pa or more, and even more preferably 20 Pa or more, from the viewpoint of improving the balance between adhesion and extensibility, and from the viewpoint of improving water retention and gel strength, and is preferably 5,000 Pa or less, more preferably 2,000 Pa or less, even more preferably 1,000 Pa or less, even more preferably 800 Pa or less, even more preferably 500 Pa or less, even more preferably 300 Pa or less, and even more preferably 200 Pa or less, from the viewpoint of improving extensibility.

[0041] The storage modulus G' and loss modulus G'' of the gel composition of the present invention were measured using a rheometer (jig: diameter 25 mm, made of PP, plate: parallel plate, diameter 8 mm) at a temperature of 25°C and a frequency of 10 -3 ~10 2 rad / s, strain: can be measured under conditions within the linear region, more specifically, by the method described in the Examples.

[0042] <Manufacturing method> The gel composition of the present invention can be produced, for example, by dissolving a polymer in water to prepare an aqueous solution (A), dissolving an aluminum salt (B') in water to prepare an aqueous solution (B) containing aluminum ions, and mixing the resulting aqueous solutions (A) and (B) using a known stirring device or the like.

[0043] [External skin preparations] The gel composition of the present invention can be suitably used for external skin preparations, that is, the external skin preparation of the present invention contains the above-mentioned gel composition of the present invention. The topical skin preparation of the present invention is applied to the skin, preferably to any part of the body, such as the face, trunk, limbs, etc., other than the scalp, and can be freely pulled or spread during use. It adheres well to the skin, provides the user with a pleasant cool feeling and sensation of use, is not sticky, and is easily peeled off from the skin after use. Even when the external skin preparation of the present invention is packed in a container that is easy to carry, such as a tube or a bag, it is easy to take out and is not left behind in the container.

[0044] The topical skin preparation of the present invention is a composition applied to the skin in the fields of cosmetics, perfumes, toiletries, pharmaceuticals, quasi-drugs, etc., and is preferably a gel-type skin care preparation, more preferably a skin care mask, and even more preferably a skin care facial mask.

[0045] The gel composition of the present invention can be used, for example, in the following manner. First, the gel composition is stretched to an appropriate size and then applied to the skin, or the gel composition is applied to the skin and then stretched to an appropriate size. Next, the gel composition is left on the skin for a certain period of time, preferably 1 minute to 8 hours, more preferably 5 minutes to 1 hour. Thereafter, the gel composition is peeled off from the skin. The gel composition can be easily peeled off, thereby achieving good skin care effects. Alternatively, the gel composition may be used while massaging, which may be done directly with the hands or with a tool such as a sponge.

[0046] Furthermore, the present invention provides a method for moisturizing skin by applying the gel composition of the present invention to the skin. [Example]

[0047] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples in any way.

[0048] [Preparation of gel composition] Example 1 (1) Preparation of polymer aqueous solution 19.0 g of anionic PVA (product name: Gohsenex (registered trademark) T-330H, manufactured by Mitsubishi Chemical Corporation, degree of polymerization = 2,000, degree of saponification > 99.0 mol%, carboxylic acid modified) and 192.1 g of ion-exchanged water were added to a 2 L container and stirred at 90°C for 2 hours or more to obtain a 9 mass% aqueous solution of anionic PVA.

[0049] (2) Preparation of aluminum salt aqueous solution 144.9 g of aluminum chloride (III) hexahydrate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and 1188.5 g of ion-exchanged water were added to a 2 L container and stirred at 50° C. for 1 hour or more to obtain a 6 mass % aqueous aluminum chloride solution.

[0050] (3) Preparation of gel composition 60.0 g of a 9% by mass anionized PVA aqueous solution and 2.57 g of a 6% by mass aluminum chloride aqueous solution prepared at 25°C were added to a 100 mL container (dedicated for hybrid mixers), and the mixture was stirred for 10 minutes using a hybrid mixer (device name: HM-500, manufactured by Keyence Corporation) (rotation conditions: revolution 2000 rpm / rotation 800 rpm, acceleration: 400 G) to obtain a gel composition.

[0051] Example 2 A gel composition was obtained in the same manner as in Example 1, except that in the preparation of the gel composition in Example 1 (3), "60.0 g of 10% by mass anionized PVA aqueous solution, 2.85 g of 6% by mass aluminum chloride aqueous solution" was used instead of "60.0 g of 9% by mass anionized PVA aqueous solution, 2.57 g of 6% by mass aluminum chloride aqueous solution."

[0052] Example 3 (1) Preparation of polymer aqueous solution In the same manner as in Example 1, an 11% by mass anionic PVA aqueous solution was obtained.

[0053] (2) Preparation of aluminum salt aqueous solution 10.0 g of aluminum chloride (III) hexahydrate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and 45.2 g of ion-exchanged water were added to a 100 mL container and stirred at 50° C. for 1 hour or more to obtain a 10 mass % aqueous aluminum chloride solution. 10.0 g of aluminum sulfate octadecahydrate (manufactured by SIGMA-ALDRICH) and 75.6 g of ion-exchanged water were added to a 100 mL container and stirred at 50° C. for 1 hour or more to obtain a 6 mass % aqueous aluminum sulfate solution. 29.0 g of the resulting 10 mass % aqueous aluminum chloride solution and 10.0 g of a 6 mass % aqueous aluminum sulfate solution were mixed to obtain an aqueous aluminum chloride / aluminum sulfate solution.

[0054] (3) Preparation of gel composition A gel composition was obtained in the same manner as in Example 1, except that in the preparation of the gel composition in Example 1 (3), "60.0 g of an 11% by mass anionic PVA aqueous solution, 2.18 g of an aluminum chloride / aluminum sulfate aqueous solution" was used instead of "60.0 g of a 9% by mass anionic PVA aqueous solution, 2.57 g of a 6% by mass aluminum chloride aqueous solution."

[0055] Example 4 In the preparation of the gel composition (3) of Example 1, a gel composition was obtained in the same manner as in Example 1, except that "60.0 g of 9 mass % anionized PVA aqueous solution, 2.57 g of 6 mass % aluminum chloride aqueous solution" was replaced with "60.0 g of 11 mass % anionized PVA aqueous solution, 3.14 g of 6 mass % aluminum chloride aqueous solution."

[0056] Example 5 In the preparation of the gel composition (3) of Example 1, a gel composition was obtained in the same manner as in Example 1, except that "60.0 g of 12% by mass anionized PVA aqueous solution, 3.42 g of 6% by mass aluminum chloride aqueous solution" was used instead of "60.0 g of 9% by mass anionized PVA aqueous solution, 2.57 g of 6% by mass aluminum chloride aqueous solution."

[0057] Example 6 In the preparation of the gel composition (3) of Example 1, a gel composition was obtained in the same manner as in Example 1, except that "60.0 g of 9 mass% anionized PVA aqueous solution, 2.57 g of 6 mass% aluminum chloride aqueous solution" was replaced with "60.0 g of 13 mass% anionized PVA aqueous solution, 3.71 g of 6 mass% aluminum chloride aqueous solution."

[0058] Example 7 A gel composition was obtained in the same manner as in Example 1, except that in the preparation of the gel composition (3) in Example 1, "60.0 g of 14% by mass anionized PVA aqueous solution, 3.99 g of 6% by mass aluminum chloride aqueous solution" was used instead of "60.0 g of 9% by mass anionized PVA aqueous solution, 2.57 g of 6% by mass aluminum chloride aqueous solution."

[0059] Example 8 A gel composition was obtained in the same manner as in Example 1, except that in the preparation of the gel composition in Example 1 (3), "60.0 g of 15% by mass anionized PVA aqueous solution, 4.28 g of 6% by mass aluminum chloride aqueous solution" was used instead of "60.0 g of 9% by mass anionized PVA aqueous solution, 2.57 g of 6% by mass aluminum chloride aqueous solution."

[0060] Example 9 In the preparation of the gel composition (3) of Example 1, a gel composition was obtained in the same manner as in Example 1, except that "60.0 g of 9 mass % anionized PVA aqueous solution, 2.57 g of 6 mass % aluminum chloride aqueous solution" was replaced with "60.0 g of 8 mass % anionized PVA aqueous solution, 2.28 g of 6 mass % aluminum chloride aqueous solution."

[0061] Example 10 In the preparation of the gel composition (3) of Example 1, a gel composition was obtained in the same manner as in Example 1, except that "60.0 g of 7% by mass anionized PVA aqueous solution, 2.00 g of 6% by mass aluminum chloride aqueous solution" was used instead of "60.0 g of 9% by mass anionized PVA aqueous solution, 2.57 g of 6% by mass aluminum chloride aqueous solution."

[0062] Example 11 In (3) Preparation of the gel composition of Example 1, a gel composition was obtained using the same method as in Example 1, except that in place of "60.0 g of a 9 mass % anionized PVA aqueous solution, 2.57 g of a 6 mass % aluminum chloride aqueous solution," "60.0 g of an 11 mass % anionized PVA aqueous solution, 0.78 g of a 6 mass % aluminum chloride aqueous solution, and 0.52 mL of 1 mol / L hydrochloric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)" were used.

[0063] Comparative Example 1 A gel composition was obtained in the same manner as in Example 1, except that in the preparation of the gel composition (3) in Example 1, "60.0 g of 6 mass% anionized PVA aqueous solution, 1.71 g of 6 mass% aluminum chloride aqueous solution" was used instead of "60.0 g of 9 mass% anionized PVA aqueous solution, 2.57 g of 6 mass% aluminum chloride aqueous solution."

[0064] Comparative Example 2 In the preparation of the gel composition (3) of Example 1, a gel composition was obtained in the same manner as in Example 1, except that "60.0 g of 9 mass % anionized PVA aqueous solution, 2.57 g of 6 mass % aluminum chloride aqueous solution" was replaced with "60.0 g of 11 mass % anionized PVA aqueous solution, 0.78 g of 6 mass % aluminum chloride aqueous solution."

[0065] [Physical property measurement and evaluation] The gel compositions obtained in the examples and comparative examples were subjected to the following physical property measurements and evaluations. The evaluation results are shown in Table 1. The amount of each component in Table 1 is shown as % by mass.

[0066] <pH of gel composition> The gel composition was filled into a 100 mL container, and the pH of the gel composition at 25°C was measured by inserting a glass electrode (manufactured by Horiba Ltd., product name: 9681S-10D) into the gel composition at 25°C.

[0067] <Storage modulus G' and loss modulus G'' of gel composition> The storage modulus G' and loss modulus G'' of the gel composition were measured using a rheometer under the following conditions. Equipment: MRC302 (Anton Paar) Jig: PP25 (Diameter: 24.985 mm) Plate: Lower Measuring Plate L-PP08 / CTD, D: 8mm for CTD450 / 600 / 1000 Temperature: 25℃ Frequency: 10 -3 ~10 2 rad / s Distortion: Within the linear region (1% distortion in this example) Based on the measurement profile obtained under the above measurement conditions, the storage modulus G' (frequency: 62.8 rad / s, 0.135 rad / s), loss modulus G'' (frequency: 62.8 rad / s, 0.135 rad / s), tan δ (frequency: 62.8 rad / s, 0.135 rad / s), and the frequency at which tan δ becomes 1 were obtained.

[0068] <Evaluation of skin adhesion> The adhesion of the gel composition to the skin was evaluated by five expert panelists. Specifically, 2 g / 9 cm of the gel composition was applied to the back of the hand. 2 After that, the back of the hand was turned over at 180°C for 120 seconds, and the state of dripping of the gel composition was observed, and the adhesion of the gel composition to the skin was evaluated based on the following evaluation criteria. (Evaluation criteria) Dripping within 1:30 seconds Dripping within 120 seconds after 2:30 seconds 3: No dripping, but the gel composition flows slightly 4: No dripping at all The average scores of the five panelists' ratings are shown in Table 1.

[0069] <Evaluation of stretchability> The extensibility of the gel compositions was evaluated by five expert panelists. Specifically, the gel composition (2 g / 9 cm 2 The gel composition was stretched by grasping both ends of the sheet (3 cm x 3 cm), and the extensibility of the gel composition was evaluated based on the following evaluation criteria. (Evaluation criteria) 1: The gel composition cannot be grasped with the hand (cannot be stretched) 2: The gel composition can be grasped by hand and stretched, but it breaks easily. 3: The gel composition can be easily grasped and spread by hand 4: The gel composition can be grasped by hand and spread very easily The average scores of the five panelists' ratings are shown in Table 1.

[0070] [Table 1]

[0071] It can be seen from Table 1 that the gel compositions of the Examples have a better balance of adhesion to the skin and extensibility than the gel compositions of the Comparative Examples. That is, it can be seen that the present invention can provide gels and topical skin preparations with an improved balance of adhesion and extensibility.< / ph>

Claims

1. The following components (A) to (C): (A) Anionic polymer: 5.0% by mass or more and 20.0% by mass or less (B) Aluminum ions 0.05% by mass or more and 0.50% by mass or less as an aluminum salt, and (C) Water Including, Component (A) is a polyvinyl alcohol having a carboxy group, which has a degree of saponification of 90 mol % or more, a degree of polymerization of 500 to 4000, and a carboxy group content of 0.1 mol % to 10 mol %, When the gel composition was subjected to dynamic viscoelasticity measurement (frequency dependence) at 25°C under strain conditions within the linear region, There is a frequency in the frequency range of 0.001 to 100 rad / s where the loss modulus G'' / storage modulus G' (tan δ) is 1, The storage modulus G' of the gel composition at 25°C and a frequency of 62.8 rad / s is 500 Pa or more. Gel composition.

2. A gel composition according to claim 1, wherein component (A) comprises one or more selected from the following (1) to (4): (1) Graft polymer or block polymer of polyvinyl alcohol and an unsaturated monomer having a carboxy group (2) Saponified copolymer of a vinyl ester compound and an unsaturated monomer having at least one group selected from a carboxy group and a carboxylic acid ester group. (3) a saponified product of a polymer of a vinyl ester compound in the presence of a chain transfer agent having a carboxy group, and (4) Reaction product of polyvinyl alcohol and a carboxylating agent

3. 3. The gel composition according to claim 1, wherein the gel composition has a storage modulus G' of 15,000 Pa or less at 25°C and a frequency of 62.8 rad / s.

4. A gel composition described in any one of claims 1 to 3, wherein the mass ratio of component (C) to component (A) [(C) / (A)] is 1.0 or more and 20.0 or less.

5. In a frequency region lower than the frequency at which tanδ is 1, the loss modulus G″ is greater than the storage modulus G′, 5. The gel composition according to claim 1, wherein in a frequency region higher than the frequency at which tan δ is 1, the storage modulus G' is greater than the loss modulus G''.

6. The gel composition according to any one of claims 1 to 5, wherein the frequency at which tan δ becomes 1 is 0.1 rad / s or more and 30.0 rad / s or less.

7. 7. The gel composition according to claim 1, wherein the storage modulus G' of the gel composition at 25°C and a frequency of 0.135 rad / s is 1 Pa or more and 5,000 Pa or less.

8. The gel composition according to any one of claims 1 to 7, further comprising sulfate ions.

9. The molar ratio of the sulfate ions to the aluminum ions contained in the gel composition (SO ４ ２－ / Al ３＋ 9. The gel composition according to claim 8, wherein the σ is 0.08 or more and 1.45 or less.

10. The gel composition according to any one of claims 1 to 9, having a pH at 25°C of 2.0 or more and 6.5 or less.

11. An external skin preparation comprising the gel composition according to any one of claims 1 to 10.

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