Oil-in-water emulsion skin cosmetic

Abstract

To provide oil-in-water type emulsified skin cosmetics that create a film with a lamellar α-gel structure on a skin surface, ensuring improved moisturizing effects even post towel-drying, along with sustained effectiveness, and satisfying user experience.SOLUTION: Oil-in-water type emulsified skin cosmetics comprise (A) an anionic surfactant: 0.05 mass% or more and 3 mass% or less, (B) higher alcohol: 0.1 mass% or more and 6 mass% or less, (C) at least one compound selected from mono fatty acid glycerol ester, di-fatty acid glycerol ester, mono fatty acid sorbitan ester and di-fatty acid sorbitan ester: 0.3 mass% or more and 12 mass% or less, (D) polypropylene glycol or its lower alkyl ether, where MH and ML, calculated from a chromatograph determined by gel permeation chromatography measurement, satisfy a relationship of a formula (1): 0.35≤ML / MH≤0.75: 0.05 mass% or more and 10 mass% or less, and (E) an organic base: 0.01 mass% or more and 1.5 mass% or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to an oil-in-water emulsion skin cosmetic. [Background technology]

[0002] As a cosmetic product with excellent sustained moisturizing effect on the skin, skin cosmetics have been reported that form a uniform and flexible lamellar α-gel structured film on the skin surface, and that contain dialkyl ethers, alkyl-modified carboxyvinyl polymers, and highly polymerized silicones in addition to oils such as higher alcohols and higher fatty acids (Patent Documents 1-3). However, when these conventional cosmetics are applied to wet skin after washing the face, showering, or bathing in an attempt to obtain sufficient moisturizing effect, they do not adhere well to the skin, and sufficient moisturizing effect cannot be obtained after towel drying. Therefore, the present inventors have found that by including one or more compounds selected from polyether-modified silicones and alkyl polyether-modified silicones in addition to higher alcohols, anionic surfactants, and specific polyhydric alcohol fatty acid esters, it is possible to obtain a skin cosmetic that forms a lamellar α-gel structure film on the skin even when applied to wet skin, exhibits high residue even after towel drying, suppresses moisture evaporation from the skin, provides a sustained moisturizing effect, and has a good feel on the skin, and have filed a patent application (Patent Document 4). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2015-227304 [Patent Document 2] Japanese Patent Publication No. 2015-227305 [Patent Document 3] Japanese Patent Publication No. 2016-222598 [Patent Document 4] Japanese Patent Publication No. 2018-203730 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] However, even with the cosmetic composition described in Patent Document 4, when applied to wet skin, the moisturizing effect after towel-drying, its duration, and the feel of use were not sufficient. Therefore, the object of the present invention is to provide an oil-in-water emulsion skin cosmetic that forms a lamellar α-gel structure film on the skin, has a higher and longer-lasting moisturizing effect even after towel drying, and has a good feel to use. [Means for solving the problem]

[0005] Therefore, the inventors conducted further studies to improve the moisturizing effect and its persistence after towel drying. As a result, they discovered that by combining an anionic surfactant, a higher alcohol, an organic base, and a glycerin fatty acid ester or sorbitan fatty acid ester with polypropylene glycol or its lower alkyl ether having a specific molecular weight distribution to create an oil-in-water emulsion composition, a lamellar α-gel structure film is formed on the skin, providing an excellent moisturizing effect with a feeling of clinging to the skin even after towel drying. This clinging power is sustained, and the oil-in-water emulsion skin cosmetic has a good feel, thus completing the present invention.

[0006] In other words, the present invention provides an oil-in-water emulsion skin cosmetic containing the following components (A), (B), (C), (D), and (E). (A) Anionic surfactant: 0.05% by mass or more and 3% by mass or less (B) Higher alcohols: 0.1% by mass or more and 6% by mass or less. (C) One or more compounds selected from monoglyceryl esters, diglyceryl esters, monoglyceryl esters, and diglyceryl esters, in an amount of 0.3% to 12% by mass. (D) M calculated from the chromatograph obtained by gel permeation chromatography measurement H and M L0.05% by mass or more and 10% by mass or less of polypropylene glycol or a lower alkyl ether thereof that satisfies the relationship of formula (1),

[0007] [Formula 1] 0.35≦M L / M H ≦0.75 ····(1)

[0008] (In formula (1), let L be the length of the perpendicular from the maximum point K at which the refractive index intensity on the chromatogram is maximum to the baseline B, let point O be the one with the shorter elution time among the two points on the chromatogram at which the refractive index intensity is L / 2, let point Q be the one with the longer elution time, let P be the intersection of the straight line G connecting point O and point Q and the perpendicular drawn from the maximum point K to the baseline, the distance between point O and the intersection P is M H and the distance between point Q and the intersection P is M L ) (E) 0.01% by mass or more and 1.5% by mass or less of an organic base

Effects of the Invention

[0009] Use of the skin cosmetic of the present invention forms a film having a lamellar α-gel structure on the skin even when applied to wet skin, allows a user to perceive an excellent moisturizing effect that provides a skin-adhesive feel even after towel drying, maintains this skin-adhesive force, and also provides favorable usage feel including good spreadability on the skin when applied to wet skin, a plump skin feel after application to wet skin and towel drying, and non-sticky skin feel.

Mode for Carrying Out the Invention

[0010] The cosmetic of the present invention is an oil-in-water emulsified skin cosmetic, and one embodiment thereof contains the following components (A), (B), (C), (D) and (E). (A) 0.05% by mass or more and 3% by mass or less of an anionic surfactant, (B) 0.1% by mass or more and 6% by mass or less of a higher alcohol, (C) One or more compounds selected from the group consisting of mono-fatty acid glycerin esters, di-fatty acid glycerin esters, mono-fatty acid sorbitan esters, and di-fatty acid sorbitan esters, in an amount of 0.3 mass% or more and 12 mass% or less, (D) M calculated from a chromatogram obtained by gel permeation chromatography measurement H and M L polypropylene glycol or a lower alkyl ether thereof satisfying the relationship of formula (1), in an amount of 0.05 mass% or more and 10 mass% or less,

[0011] [Number 2] 0.35≦M L / M H ≦0.75 ····(1)

[0012] (In formula (1), let L be the length of the perpendicular line from the maximum point K at which the refractive intensity on the chromatogram is maximum to the baseline B, let point O be the point with the earlier elution time among the two points on the chromatogram at which the refractive intensity is L / 2, let point Q be the point with the later elution time, let P be the intersection of the straight line G connecting point O and point Q and the perpendicular line drawn from the maximum point K to the baseline, let the distance between point O and intersection P be M H and let the distance between point Q and intersection P be M L ) (E) an organic base in an amount of 0.01 mass% or more and 1.5 mass% or less

[0013] Component (A) in the present invention is an anionic surfactant, which has the function of forming emulsified particles in an oil-in-water emulsified skin cosmetic into a lamellar structure and forming a lamellar film (α-gel) on the skin. The anionic surfactant of component (A) is not limited as long as it is commonly used in cosmetics, for example, fatty acids with 12 to 22 carbon atoms or their salts, such as sodium laurate, potassium palmitate, and arginine stearate; alkyl sulfate esters with 12 to 22 carbon atoms or their salts, such as sodium lauryl sulfate and potassium lauryl sulfate; alkyl ether sulfate esters with 12 to 22 carbon atoms or their salts, such as polyoxyethylene lauryl sulfate triethanolamine; acyl sarcosine with 12 to 22 carbon atoms or its salts, such as sodium lauroyl sarcosinate; alkyl phosphates with 12 to 22 carbon atoms or their salts, such as sodium monostearyl phosphate; sodium polyoxyethylene oleyl ether phosphate, polyoxyethylene Examples include polyoxyethylene alkyl ether phosphates with 12 to 22 carbon atoms, such as sodium tearyl ether phosphate, or salts thereof; dialkyl sulfosuccinates with 12 to 24 carbon atoms, such as sodium di-2-ethylhexyl sulfosuccinate, or salts thereof; N-alkylyl methyl taurates with 12 to 22 carbon atoms, such as sodium N-stearoyl-N-methyl taurate, or salts thereof; acyl glutamates with 12 to 22 carbon atoms, such as sodium dilauroyl glutamate, monosodium N-lauroyl glutamate, sodium N-stearoyl-L-glutamate, N-stearoyl-L-glutamate arginine, sodium N-stearoyl glutamate, and sodium N-myristoyl-L-glutamate, or salts thereof.

[0014] As the anionic surfactant of component (A), it is preferable to use something other than fatty acids or salts thereof, and it is preferable to use one or more selected from polyoxyethylene alkyl ether phosphate with 12 to 22 carbon atoms or salts thereof, sodium N-alkylylmethyl taurate with 12 to 22 carbon atoms, and acyl glutamate with 12 to 22 carbon atoms. From the viewpoint of applying it to wet skin and obtaining and maintaining a feeling of clinging to the skin after towel drying, sodium N-alkylylmethyl taurate with 12 to 22 carbon atoms, acyl glutamate with 12 to 22 carbon atoms or salts thereof are more preferable. As the acyl glutamate with 12 to 22 carbon atoms, N-stearoyl-L-glutamate is preferred, and it is more preferable to use at least one selected from N-stearoyl-L-glutamate arginine salt and N-stearoyl-L-glutamate potassium salt.

[0015] Component (A) can be used alone or in combination of two or more types. From the viewpoint of creating a lamellar structure in the emulsion particles in the skin cosmetic, forming a lamellar film (α-gel) on the skin, applying it to wet skin to obtain a feeling of clinging to the skin after towel drying, maintaining that feeling, and obtaining a good usability, the content, excluding the counterions, is preferably 0.05% by mass or more and 3% by mass or less in the total composition, preferably 0.08% by mass or more and 2% by mass or less, and more preferably 0.1% by mass or more and 1.5% by mass or less.

[0016] Component (B) is a higher alcohol that forms a lamellar structure in the emulsion particles in the skin cosmetic, creating a lamellar film (α-gel) on the skin, and also contributes to moisturizing and the sustained effect of moisturizing. As the higher alcohol of component (B), linear saturated alcohols having 12 to 22 carbon atoms are preferred, such as lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, and behenyl alcohol. Of these, linear saturated alcohols having 14 to 22 carbon atoms are preferred, linear saturated alcohols having 16 to 22 carbon atoms are more preferred, and from the viewpoint of improving the persistence of the moisturizing effect, at least one selected from cetyl alcohol and stearyl alcohol is even more preferred, and it is even more preferable to include both cetyl alcohol and stearyl alcohol. When cetyl alcohol and stearyl alcohol are included, they may be blended independently or mixed, or a mixture thereof, cetostearyl alcohol, may also be included.

[0017] Component (B) can be used alone or in combination of two or more types. From the viewpoint of creating a lamellar structure in the emulsion particles in the skin cosmetic, forming a lamellar film (α-gel) on the skin, and obtaining a feeling that adheres to wet skin even after towel-drying when applied to wet skin, and from the viewpoint of its persistence, the content is 0.1% by mass or more and 6% by mass or less in the total composition, preferably 0.2% by mass or more and 5% by mass or less, and more preferably 0.3% by mass or more and 4% by mass or less.

[0018] Component (C) is one or more compounds selected from monoglyceryl esters, diglyceryl esters, monoglyceryl esters, and diglyceryl esters. Component (C) has the function of creating a lamellar structure in the emulsion particles in the skin cosmetic, forming a lamellar film (α-gel) on the skin, and providing and maintaining a feeling of clinging to wet skin even after towel-drying when applied to wet skin. The fatty acids constituting these compounds preferably have 12 to 22 carbon atoms, and more preferably 16 to 18 carbon atoms, from the viewpoint of creating a lamellar structure in the emulsion particles in the skin cosmetic, forming a lamellar film (α-gel) on the skin, and maintaining a feeling of clinging to wet skin even after towel-drying when applied to wet skin. As component (C), from the viewpoint of fully exhibiting the function of component (C) above, at least one selected from monoglyceryl fatty acid esters and sorbitan difatty acid esters is preferred. Among monoglyceryl fatty acid esters, monoglyceryl behenate is preferred, and among sorbitan difatty acid esters, sorbitan distearate is preferred, and at least one selected from monoglyceryl behenate and sorbitan distearate is preferred, and it is more preferable to contain both monoglyceryl behenate and sorbitan distearate.

[0019] Component (C) can be used alone or in combination of two or more types. From the viewpoint of creating a lamellar structure in the emulsion particles in the skin cosmetic, forming a lamellar film (α-gel) on the skin, and obtaining and maintaining a feeling of clinging to wet skin even after towel-drying when applied to wet skin, the content is 0.3% by mass or more and 12% by mass or less in the total composition, preferably 0.5% by mass or more and 10% by mass or less, and more preferably 1% by mass or more and 8% by mass or less.

[0020] In the present invention, the mass ratio of component (A) to the total amount of components (B) and (C) [(B)+(C)] is preferably (A) / [(B)+(C)] = 0.05 or more, more preferably 0.08 or more and 0.4 or less, and even more preferably 0.1 or more and 0.3 or less, from the viewpoint of creating a lamellar structure for the emulsion particles in the skin cosmetic, obtaining a feeling of clinging to wet skin even after application to wet skin and towel drying, and maintaining that feeling. Furthermore, the mass ratio of component (B) to the total amount of components (B) and (C) [(B)+(C)] is preferably (B) / [(B)+(C)] = 0.2 to 0.75, more preferably 0.25 to 0.6, and even more preferably 0.3 to 0.5, from the viewpoint of creating a lamellar structure for the emulsion particles in the skin cosmetic, obtaining a feeling of clinging to wet skin even after towel-drying when applied to wet skin, and maintaining that feeling.

[0021] Component (D) is calculated from the chromatograph obtained by gel permeation chromatography. H and ML The two are polypropylene glycol or its lower alkyl ether that satisfies the relationship in formula (1).

[0022] [Math 3] 0.35≦M L / M H ≤0.75 ····(1)

[0023] (In equation (1), let L be the length of the perpendicular from the maximum point K on the chromatogram where the refractive index intensity is maximum to the baseline B. Of the two points on the chromatogram where the refractive index intensity is L / 2, let O be the one with the earlier elution time and Q be the one with the later elution time. Let P be the intersection of the line G connecting points O and Q and the perpendicular drawn from the maximum point K to the baseline. Then, let M be the distance between point O and the intersection point P.) H Let M be the distance between point Q and intersection point P. L (Assume) Ingredient (D) is the main ingredient that provides excellent moisturizing effects, leaving the skin feeling supple even after towel-drying, and has the function of maintaining that suppleness.

[0024] The polyalkylene glycol or its lower alkyl ether, component (D) used in the present invention, is defined by a chromatogram obtained using a differential refractometer in gel permeation chromatography (GPC), as described in Japanese Patent Application Publication No. 2018-104342. This chromatogram is a graph that shows the relationship between refractive index intensity and elution time, with the horizontal axis representing elution time and the vertical axis representing the refractive index intensity obtained using a differential refractometer. When the sample solution is injected into the gel permeation chromatograph and developed, elution begins with the molecule with the highest molecular weight, and the elution curve rises as the refractive index intensity increases. After that, once the maximum point K where the refractive index intensity is at its maximum is passed, the elution curve begins to decline. ML / MH are calculated from the chromatogram as follows: (1) Draw a perpendicular line from the point of maximum refractive index intensity K on the chromatogram to the baseline B, and let the length of the perpendicular line be L. (2) Of the two points on the chromatogram where the refractive index intensity is L / 2, the point with the earlier elution time is designated as point O, and the point with the later elution time is designated as point Q. (3) Let P be the intersection of the line G connecting point O and point Q and the perpendicular line drawn from the point of maximum refractive index intensity K to baseline B.

[0025] In equation (1) above, M L / M H From the viewpoint of preventing a decrease or increase in the viscosity of polypropylene glycol or its lower alkyl ether, the viscosity is 0.35 to 0.75, preferably 0.36 to 0.75, and more preferably 0.36 to 0.62. Furthermore, the average number of moles of oxypropylene groups added to polypropylene glycol is preferably 50 to 250, and more preferably 50 to 150, from the viewpoint of preventing a decrease in viscosity of the skin cosmetic composition of the present invention, obtaining an excellent moisturizing effect that gives the skin a sticky feel even after towel drying, and obtaining the function of maintaining that stickiness to the skin. Furthermore, alkyl ethers having 1 to 6 carbon atoms are preferred as the lower alkyl ether derivative.

[0026] Furthermore, it is preferable that component (D) has a chromatogram in which the refractive index intensity and elution time obtained using a differential refractometer in gel permeation chromatography are asymmetric, and that the asymmetric value As of the peak of the chromatogram, which is determined as shown below, satisfies the relationship between equations (2) and (3) below.

[0027] [Math 4]

[0028] As = W1 / 2 / W5% ... (2) 0.30 ≤ As ≤ 0.70 ···(3)

[0029] (In equation (2), of the two points on the chromatogram where the refractive index intensity is L / 20, let R be the point with the earlier elution time, and let S be the point with the later elution time. Let T be the intersection of the line H connecting points R and S and the perpendicular line drawn from the maximum point K to the baseline B. Let W1 / 2 be the distance between point R and intersection T, and W5% be the distance between point R and point S.)

[0030] As can be calculated as follows, as described in Japanese Patent Publication No. 2018-104342. (1) Draw a perpendicular line from the point of maximum refractive index intensity K on the chromatogram to the baseline B, and let its length be L. (2) Of the two points on the chromatogram where the refractive index intensity is L / 20, the point with the earlier elution time is designated as point R, and the point with the later elution time is designated as point S. (3) Let T be the intersection of the line H connecting point R and point S and the perpendicular line drawn from the point K, where the refractive index intensity is maximum, to the baseline B. (4) Let the distance between point R and intersection point T be W1 / 2, and the distance between point R and point S be W5%.

[0031] In formula (3), the value of As is preferably 0.30 to 0.70, more preferably 0.35 to 0.65, and even more preferably 0.50 to 0.65, from the viewpoint of preventing a decrease or increase in the viscosity of polypropylene glycol or its lower alkyl ether.

[0032] In the present invention, M L M H For determining As, gel permeation chromatography (GPC) is performed as described in Japanese Patent Publication No. 2018-104342. The system consists of a SHODEX® GPC101 GPC-dedicated system, a SHODEX RI-71s differential refractometer, a SHODEX KF-G guard column, and three SHODEX KF804L columns mounted in sequence. The column temperature is 40°C, and tetrahydrofuran is flowed at a flow rate of 1 ml / min as the developing solvent. 0.1 ml of a 0.1 wt% tetrahydrofuran solution of the resulting reaction is injected, and a chromatogram representing refractive index intensity and elution time is obtained using the BORWIN GPC calculation program.

[0033] Specifically, the preferred polypropylene glycol or its lower alkyl ether is polypropylene glycol, its methyl ether, its ethyl ether, its propyl ether, or its butyl ether; more preferably polypropylene glycol, its methyl ether, its ethyl ether, its propyl ether, or its butyl ether; and even more preferably polypropylene glycol, its methyl ether, its ethyl ether, its propyl ether, or its butyl ether. A commercially available product containing the ingredient (D) is Acrobeute. TM MB-52, Acrobeute TM Examples include MB-90 (manufactured by NOF Corporation).

[0034] Component (D) can be used alone or in combination of two or more types. From the viewpoint of obtaining and maintaining a feeling of clinging to wet skin even after towel-drying when applied to wet skin, the content is preferably 0.05% by mass or more and 10% by mass or less, more preferably 0.1% by mass or more and 8% by mass or less, and more preferably 0.5% by mass or more and 5% by mass or less in the total composition.

[0035] The mass ratio of component (D) to the total amount of components (A), (B), and (C) [(A)+(B)+(C)] is preferably (D) / [(A)+(B)+(C)] = 0.05 or more and 6 or less, more preferably 0.2 or more and 4 or less, and even more preferably 0.45 or more and 3 or less, from the viewpoint of creating a lamellar structure for the emulsion particles in the skin cosmetic, obtaining a feeling of clinging to wet skin even after towel drying when applied to wet skin, and maintaining that feeling.

[0036] Component (E) is an organic base that forms a lamellar structure in the emulsion particles of the skin cosmetic, creating a lamellar film (α-gel) on the skin. It has the function of providing and maintaining a feeling of clinging to wet skin, even after towel-drying when applied to wet skin. Examples of organic bases include one or more selected from alkylamines having an alkyl group with 1 to 6 carbon atoms, alkanolamines having an alkyl group with 1 to 6 carbon atoms, and basic amino acids. Specifically, alkylamines having an alkyl group with 1 to 6 carbon atoms include methylamine, ethylamine, propylamine, butylamine, hexylamine, dimethylamine, and diethylamine. Alkanolamines having an alkyl group with 1 to 6 carbon atoms include monoethanolamine, diethanolamine, triethanolamine, N-methyl-diethanolamine, N,N-dimethylmonoethanolamine, and aminomethylpropanol, with aminomethylpropanol being preferred. Basic amino acids include lysine, histidine, and arginine, with arginine being preferred. Among arginines, L-arginine is preferred. Of these, from the viewpoint of creating a lamellar structure for the emulsion particles in the skin cosmetic, forming a lamellar film (α-gel) on the skin, and providing a function to obtain and maintain a feeling of clinging to wet skin even after towel-drying when applied to wet skin, at least one selected from alkanolamines having an alkyl group with 1 to 6 carbon atoms and basic amino acids is preferred, at least one selected from alkanolamines having an alkyl group with 3 to 6 carbon atoms and basic amino acids is more preferred, basic amino acids are even more preferred, at least one selected from aminomethylpropanol and arginine is even more preferred, and arginine is even more preferred. Among arginine, L-arginine is preferred.

[0037] Component (E) can be used alone or in combination of two or more types. From the viewpoint of creating a lamellar structure in the emulsion particles in the skin cosmetic, forming a lamellar film (α-gel) on the skin, and providing a feeling of clinging to wet skin even after towel-drying when applied to wet skin, and maintaining that feeling, the content is preferably 0.01% by mass or more and 1.5% by mass or less, and preferably 0.03% by mass or more and 0.5% by mass or less, in the total composition.

[0038] In the present invention, the mass ratio of component (E) to component (A) ((E) / (A)) is preferably 0.1 to 1, more preferably 0.2 to 0.8, and even more preferably 0.3 to 0.4, from the viewpoint of creating a lamellar structure for the emulsion particles in the skin cosmetic, forming a lamellar film (α-gel) on the skin, and providing a feeling of clinging to wet skin even after towel-drying when applied to wet skin, and maintaining that feeling.

[0039] In the skin cosmetic composition of the present invention, it is preferable to include nonionic surfactants other than component (C) above, and it is preferable to include nonionic surfactants of component (F)HLB10-16 in both the aqueous and oil phases in order to improve the skin compatibility of the skin cosmetic composition of the present invention. It is more preferable to include the nonionic surfactant (F)HLB10-16 in an amount of 0.01% to 1.5% by mass on the aqueous phase side and 0.01% to 1.5% by mass on the oil phase side, it is even more preferable to include the nonionic surfactant (F)HLB10-16 in an amount of 0.1% to 1% by mass on the aqueous phase side and 0.1% to 1% by mass on the oil phase side, and it is even more preferable to include the nonionic surfactant (F)HLB10-16 in an amount of 0.2% to 0.8% by mass on the aqueous phase side and 0.2% to 0.8% by mass on the oil phase side. Similarly, from the viewpoint of improving the skin compatibility of the skin cosmetic composition of the present invention, the mass ratio (F1 / F2) of the component (F) in the aqueous phase side (F1) to the oil phase side (F2) is preferably 0.1 to 10, more preferably 0.5 to 5, and even more preferably 1 to 3. In this case, the nonionic surfactant used on the aqueous phase side and the nonionic surfactant used on the oil phase side may be the same or different.

[0040] Examples of nonionic surfactants of (F)HLB10~16 include ethylene glycol fatty acid esters such as ethylene glycol monostearate; polyethylene glycol fatty acid esters such as polyethylene glycol (2) monostearate; polyalkylene glycol alkyl ethers such as polyethylene glycol (5) decylpentadecyl ether and polyoxyethylene (20) isocetyl ether; polyethylene glycol hydrogenated castor oil such as polyethylene glycol (5) hydrogenated castor oil and polyoxyethylene (60) hydrogenated castor oil; propylene glycol fatty acid esters; glycerin alkyl ethers such as glycerin monoisostearyl ether and glycerin monostearyl ether; fatty acid alkanolamides; fatty acid dialkanolamides such as lauric acid diethanolamide; and polyoxyethylene sorbitan monostearate. Of these nonionic surfactants, at least one selected from polyethylene glycol hydrogenated castor oil and glycerin alkyl ether is preferred. Hydrogenated castor oil containing cellulose glycol is more preferable. In this invention, the HLB value is an indicator of the hydrophilic-lipophilic balance, and in this invention, the value calculated by the following formula by Oda and Teramura et al. is used.

[0041] Furthermore, in the present invention, the skin cosmetic composition is preferably made to contain a polyol of trivalent or higher with a molecular weight of 500 or less, in order to further improve the function of obtaining and maintaining a feeling of clinging to wet skin even after application to wet skin and towel drying, and to suppress the sticky feeling when sweat or water adheres to the skin after application to wet skin and towel drying, and to further improve the feeling of clinging to the skin. Component (G) Examples of polyols with a molecular weight of 500 or less and a valent or higher include glycerin, diglycerin, triglycerin, and other polyglycerins with a molecular weight of 500 or less. Of these, glycerin is more preferred. Component (G) is preferably contained in the total composition at a concentration of 1% to 30% by mass, more preferably 3% to 25% by mass, and even more preferably 5% to 20% by mass, from the viewpoint of suppressing stickiness when sweat or water adheres to the skin after application to wet skin and towel drying, and further improving the feeling of adhesion to the skin.

[0042] Furthermore, in the present invention, in order to further improve the function of obtaining and maintaining a feeling of clinging to wet skin even after being applied to wet skin and towel-drying, and to suppress the sticky feeling when sweat or water adheres to the skin after being applied to wet skin and towel-drying, and to further improve the feeling of clinging to the skin, it is preferable to further include, in addition to component (G), one or more selected from component (H) glycols with a number average molecular weight of 2000 or less and component (I) liquid hydrocarbon oil. Examples of glycols with a number-average molecular weight of 2000 or less include ethylene glycol, polyethylene glycol with a number-average molecular weight of 2000 or less, propylene glycol, polypropylene glycol with a number-average molecular weight of 2000 or less, and butylene glycol. Component (H) is preferably present in the total composition at a concentration of 0.1% to 5% by mass, more preferably at a concentration of 0.3% to 4% by mass, and even more preferably at a concentration of 0.5% to 3% by mass, from the viewpoint of suppressing stickiness when sweat or water adheres to wet skin after towel drying and further improving the feeling of adhesion to the skin. Examples of component (I) liquid hydrocarbon oils include liquid paraffin, squalane, and liquid petrolatum. Furthermore, from the viewpoint of suppressing the sticky feeling when sweat or water adheres to the skin after application to wet skin and towel drying, and further improving the feeling of adhesion to the skin, component (I) is preferably contained in the total composition at a concentration of 0.1% to 5% by mass, more preferably at a concentration of 0.3% to 4% by mass, and even more preferably at a concentration of 0.5% to 3% by mass.

[0043] In addition to component (G), components (H) and (I) may be included in one or more forms, but it is more preferable to use component (G) and component (H) in combination, component (G) and component (I) in combination, or component (G), component (H), and component (I) in combination. When component (G) and component (H) are present, the mass ratio of component (G) to component (H) (G / H) is preferably 1 or more and 30 or less, more preferably 2 or more and 25 or less, and even more preferably 3 or more and 20 or less. When component (G) and component (I) are present, the mass ratio of component (G) to component (I) (G / I) is preferably 1 or more and 30 or less, more preferably 2 or more and 25 or less, and even more preferably 3 or more and 20 or less.

[0044] Furthermore, the skin cosmetic composition of the present invention preferably contains one or more silicones selected from polyether-modified silicones and alkyl-polyether-modified silicones, from the viewpoint of providing excellent moisture-occluding properties to the film on the skin. As the polyether-modified silicone, compounds represented by the following general formula (1) are preferred.

[0045] [ka]

[0046] (In the formula, R 1 The elements may be the same or different, each representing an alkyl group with 1 to 4 carbon atoms. p represents a number between 0 and 1000, and q represents a number between 1 and 1000. X 1 and X 2 These may be the same or different, and each represents a hydroxyl group, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group, respectively. 2 represents a hydrogen atom, or an alkyl group having 1 to 4 carbon atoms, or an acyl group having 2 to 4 carbon atoms. a represents a number between 1 and 4, b represents a number between 1 and 100, and c represents a number between 0 and 50. / indicates that each component unit marked with p, q, and each component unit marked with b, c may be random or in blocks.

[0047] In the above general formula (1), R 1 The group is preferably a methyl group. X 1 and X 2 The group is preferably an alkyl group having 1 to 3 carbon atoms, and more preferably a methyl group. R 2 Preferably, it is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an acyl group having 2 to 3 carbon atoms, and more preferably a hydrogen atom.

[0048] In the above general formula (1), p is a number between 0 and 1, preferably 1 and 1000 or less, preferably 100 or less, and more preferably 10 or less. q is a number between 1 and 1, preferably 100 or less, and more preferably 20 or less. In the above general formula (1), a is preferably a number between 1 and 3. In the above general formula (1), b is a number that is 1 or more, preferably 2 or more, more preferably 3 or more, and 100 or less, preferably 50 or less, more preferably 30 or less, even more preferably 15 or less, and even more preferably 8 or less. In the above general formula (1), c is a number that is 0 or greater, and 50 or less, preferably 30 or less, more preferably 10 or less, and even more preferably 3 or less, and may be 0.

[0049] The HLB value of the compound represented by the above general formula (1) is preferably 4 or higher, more preferably 6 or higher, even more preferably 8 or higher, and even more preferably 10.5 or higher, from the viewpoint of moisture-occluding properties, moisturizing effect, and feel, and from the same viewpoint, it is preferably 20 or lower, more preferably 18 or lower, even more preferably 16 or lower, even more preferably 15 or lower, and even more preferably 14.5 or lower.

[0050] The HLB value of the compound represented by the above general formula (1) can be determined by the following formula. HLB value = Molecular weight of polyoxyethylene in the compound represented by general formula (1) × 20 / Molecular weight of the compound represented by (b1) Furthermore, a, b, c, p, q, R 1 , R 2 , X 1 and X 2 This can be determined using NMR, etc.

[0051] Alkyl polyether-modified silicones include those having polyether modification as shown in general formula (1), as well as linear alkyl modification or branched alkyl modification. Examples of alkyl groups used in alkyl modification include linear or branched alkyl groups having 6 to 24 carbon atoms. Furthermore, the silicone chain may be linear or branched.

[0052] The kinematic viscosity (mm²) of the aforementioned silicones 2 The kinematic viscosity ( / s) is preferably 1 or more, more preferably 5 or more, and even more preferably 10 or more, from the viewpoint of moisture-blocking properties, moisturizing effect, and usability, and from the same viewpoint, preferably 1500 or less, more preferably 1000 or less, even more preferably 500 or less, and even more preferably 100 or less. Here, the kinematic viscosity is the value measured at 25°C using an Ubbelohde viscometer (manufactured by Shibata Scientific Co., Ltd.).

[0053] Commercially available silicones can be used, and examples of commercially available silicones include KF618 (PEG6 methyl ether dimethicone (in formula (1), R 2 =methyl, b=6), KF6011 (PEG11 methyl ether dimethicone (in formula (1), R 2 =methyl, b=11), KF6016(PEG9 methyl ether dimethicone (in formula (1), R 2 =methyl, b=9), KF615A (PEG / PPG-27 / 9-butyl ether dimethicone (in formula (1), R 2 =Butyl, b=20, c=22), KF6043 (PEG10 dimethicone (in formula (1), R 2 Examples include H and b=10 (both manufactured by Shin-Etsu Chemical Co., Ltd.).

[0054] The aforementioned silicones can be used individually or in combination of two or more, and have moisture-blocking properties. From the viewpoint of moisturizing effect and usability, the content is preferably 0.001% by mass or more and 4% by mass or less in the total composition, more preferably 0.005% by mass or more and 2% by mass or less, even more preferably 0.005% by mass or more and 1.5% by mass or less, and even more preferably 0.01% by mass or more and 1% by mass or less.

[0055] The skin cosmetic composition of the present invention may further contain oils other than the above-mentioned components (B) and (I), which can further enhance the moisturizing effect. Such oils are not limited to those other than components (B) and (I), as long as they are commonly used in cosmetics, and may be liquid, solid, or semi-solid at 25°C. Examples of liquid oils include: oils such as methyl butyl ether, ethylene glycol dioctyl ether, and glycerol monooleyl ether; ester oils such as octyldodecyl myristate, isopropyl palmitate, butyl stearate, di-2-ethylhexyl adipate, neopentyl glycol dicaprate, trioctanoin, and alkyl benzoate esters; silicone oils such as dimethylpolysiloxane, cyclic dimethylpolysiloxane, methylphenylpolysiloxane, amino-modified silicone, carboxy-modified silicone, alcohol-modified silicone, alkyl-modified silicone, and fluorine-modified silicone; and fluorinated oils such as perfluoroalkyl ethyl phosphate, perfluoroalkyl polyoxyethylene phosphate, perfluoropolyether, and polytetrafluoroethylene. These oils may also be plant-derived.

[0056] Examples of solid oils that can be used at 25°C include animal waxes, vegetable waxes, mineral waxes, and synthetic waxes. More specifically, examples of ester waxes include rice bran wax, carnauba wax, candelilla wax, beeswax, and gypsum wax, while examples of hydrocarbon waxes include ceresin, paraffin wax, microcrystalline wax, polyethylene wax, and polyolefin wax.

[0057] Examples of semi-solid oils at 25°C include cholesteryl isostearate, cholesteryl hydroxystearate, cholesteryl macadamia nut oil fatty acid, cholesterol derivatives such as N-lauroyl-L-glutamic acid di(cholesteryl-behenyl-octyldodecyl); N-lauroyl-L-glutamic acid di(phytosteryl-behenyl-2-octyldodecyl), N-lauroyl-L-glutamic acid di(phytosteryl-2-octyldodecyl) Examples include phytosterol derivatives such as phytosteryl isostearate and phytosteryl oleate; dipentaerythritol fatty acid esters such as dipentaerythritol hexaoxystearate and dipentaerythritol rosinate; triglycerides such as tri(caprylic / caprin / myristic / stearic acid) glyceride; partially hydrogenated triglycerides such as hydrogenated oils, lanolin, lanosterol derivatives, and petrolatum.

[0058] One or more types of oils can be used, and from the viewpoint of improving the stability of the lamellar structure formed by the composition of the present invention and from the viewpoint of moisturizing properties, the content is preferably 0.5% by mass or more and 10% by mass or less in the total composition, more preferably 1% by mass or more and 9% by mass or less, and even more preferably 2% by mass or more and 8% by mass or less.

[0059] In addition to the above-mentioned components, the skin cosmetic composition of the present invention may further contain, as appropriate, components commonly used in cosmetics, such as water, thickeners, disinfectants, moisturizers, humectants, colorants, preservatives, texture enhancers, powders, fragrances, anti-inflammatory agents, whitening agents, antiperspirants, UV absorbers, antioxidants, and the like. In the skin cosmetic composition of the present invention, water is used as a solvent and constitutes the remainder of each component. The combination of components (A) to (E) allows for the formation of a stable lamellar structure in the cosmetic composition. From the viewpoint of improving stability, the water content is preferably 60% to 99% by mass, and more preferably 70% to 95% by mass, in the total composition.

[0060] The skin cosmetic of the present invention can be manufactured by conventional methods and is an oil-in-water emulsion cosmetic. For example, component (E) (if component (G) is included, (E) and (G), and if component (H) is also included, (E), (G) and (H)) are mixed with water, dissolved at 60-95°C, and homogenized to form the aqueous phase. Components (A), (B), (C), (D) and (F) (if component (I) is included, components (A), (B), (C), (D), (F) and (I)) are mixed, dissolved at 70-100°C, and homogenized to form the oil phase. The aqueous phase and oil phase are mixed and homogenized, and the mixture can be manufactured by cooling to preferably 5-30°C, more preferably 10-28°C, and even more preferably 15-26°C. The skin cosmetic of the present invention can be further manufactured by the following method, and is an oil-in-water emulsion cosmetic. For example, components (E) and (F1) (if component (G) is included, components (E), (F1), and (G); if component (H) is also included, components (E), (F1), (G), and (H)) are mixed with water, dissolved at 60-95°C, and homogenized to form the aqueous phase. Components (A), (B), (C), (D), and (F2) (if component (I) is included, components (A), (B), (C), (D), (F2), and (I)) are mixed, dissolved at 70-100°C, and homogenized to form the oil phase. The aqueous phase and oil phase are mixed and homogenized, and the mixture can be manufactured by cooling to preferably 10-40°C, more preferably 15-35°C, and even more preferably 20-30°C.

[0061] The skin cosmetic of the present invention can be, for example, a lotion, emulsion, cream, gel, or serum. It can also be a sheet-like cosmetic impregnated or coated onto a sheet-like substrate such as a woven fabric or nonwoven fabric. The skin cosmetic of the present invention can be used by applying it to the skin, preferably excluding the scalp, and more preferably to the face, body, hands, feet, etc. It may be used when the skin is wet, such as after washing the face.

[0062] The skin cosmetic composition of the present invention forms a lamellar structure by containing components (A) to (E) in specific proportions. When applied to the skin, a cosmetic film is formed on the skin surface as the water evaporates. The lamellar structure can be confirmed by wide-angle X-ray diffraction. [Examples]

[0063] The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0064] Examples 1-14, Comparative Examples 1-9 Skin cosmetics with the compositions shown in Tables 1 to 5 were manufactured, and the presence or absence of lamellar structure formation was observed. Furthermore, the following were evaluated: (1) how easily the product blends into the skin when applied to wet skin; (2) the adhesive strength immediately after applying to wet skin and towel-drying; (3) the duration of the adhesive strength after applying to wet skin and towel-drying (after 30 minutes); (4) the ability to suppress stickiness when sweat adheres to the skin after applying to wet skin and towel-drying, and the boosting effect on the adhesive strength to the skin when water adheres to the skin after applying to wet skin and towel-drying; (5) the supple feeling of the skin after applying to wet skin and towel-drying; and (6) the lack of stickiness on the skin after applying to wet skin and towel-drying. The results are shown in Tables 1 to 5.

[0065] (Manufacturing method) The aqueous phase components, containing component (E) and optionally components (F1), (G), and (H), were stirred and dissolved at 70-80°C to form the aqueous phase. Next, the oil phase components, containing components (A), (B), (C), (D), (F2) and optionally component (I), were stirred and dissolved at 85-95°C to form the oil phase. The oil phase was added to the aqueous phase while stirring at 85-95°C, and then cooled to room temperature (25°C) while further stirring to produce a skin cosmetic (oil-in-water emulsion cosmetic).

[0066] (Evaluation method) (1) How easily it blends into the skin when applied to wet skin Ten expert panelists cleansed the inside of their forearms, gently wiped away any water droplets from the skin surface with a Kimtowel, and then applied 0.002 g / cm2 of each skin cosmetic. They evaluated how well the products blended into the skin upon application. ○; familiar ×; poor compatibility

[0067] (2) Adhesion strength immediately after application to wet skin and towel drying, (3) Duration of adhesion strength after application to wet skin and towel drying (after 30 minutes) After washing the inner forearm, water droplets were gently wiped off the skin surface with a Kimwipe, and each skin cosmetic was applied at a rate of 0.002 g / cm². After gently pressing down twice with a Kimwipe, the suction force was evaluated using a handy lab tester (Trinity Labs) immediately afterward and again 30 minutes later, using the tack value (load: 200 gf ± 20 gf, probe: 2 cmφ, stainless steel). The tack value was obtained by pressing the probe perpendicularly against the horizontal inner forearm until a load of 200 gf was achieved, and then releasing it. ◎◎:-32gf or less ◎: -31gf to -24gf ○: -23gf to -16gf △: -15gf to -8gf ×: -7gf or higher

[0068] (4) After applying to wet skin and towel-drying, it suppresses stickiness when sweat adheres to the skin, and after applying to wet skin and towel-drying, it boosts the skin's ability to absorb water when it adheres to the skin. After washing the inner forearm, water droplets were gently wiped off the skin surface with a Kimwipe, and each skin cosmetic was applied at a rate of 0.002 g / cm². After gently pressing twice with a Kimwipe, 0.002 g / cm² of water was applied 30 minutes after application. After 5 minutes, the suction force was evaluated using a handy lab tester (Trinity Labs) with the tack value (load: 200 gf ± 20 gf, probe: 2 cmφ, stainless steel). The tack value was obtained by pressing the probe perpendicularly against the horizontal inner forearm until a load of 200 gf was reached, and then releasing it. ◎◎:-32gf or less ◎: -31gf to -24gf ○: -23gf to -16gf △: -15gf to -8gf ×: -7gf or higher

[0069] (5) Apply to wet skin and feel the skin's plumpness after towel drying. Ten expert panelists cleansed the inside of their forearms, gently wiped away water droplets from the skin surface with Kimwipes, and applied 0.002 g / cm2 of each skin cosmetic. They then gently pressed the area twice with Kimwipes. After 5 minutes, they pressed the inside of their forearms twice with their hands, evaluated the "moisture-like" feeling, and calculated the average value. 5; It has a very chewy texture. 4; It has a chewy texture. 3; It has a slightly chewy texture. 2; It doesn't have much of a chewy texture. 1; It lacks a chewy texture.

[0070] (6) No stickiness on the skin after applying to wet skin and towel-drying. Ten expert panelists cleansed the inside of their forearms, gently pressed a Kimwipe to remove water droplets from the skin surface, and applied 0.002 g / cm2 of each skin cosmetic. They then gently pressed the Kimwipe twice over the area. After 5 minutes, they ran their hands back and forth across the inside of their forearms to evaluate the lack of stickiness, and calculated the average value. 5; Almost non-sticky 4; Non-sticky 3; Not very sticky 2; Slightly sticky 1; sticky

[0071] [Table 1]

[0072] [Table 2]

[0073] [Table 3]

[0074] [Table 4]

[0075] [Table 5]

[0076] Tables 1 to 5 show that the skin cosmetic of the present invention forms a lamellar film on the skin, and even after being applied to wet skin and towel-dried, it provides a feeling of clinging to the wet skin, and this effect is sustained. Furthermore, it offers good usability, including how easily it blends into the skin when applied to wet skin, the supple feeling of the skin after application to wet skin and towel-drying, and the absence of stickiness.

Claims

1. An oil-in-water emulsion skin cosmetic comprising the following ingredients (A), (B), (C), (D), and (E). (A) N-Acyl glutamic acid with 12 to 22 carbon atoms or its salt, 0.05% by mass or more and 3% by mass or less. (B) 0.1% to 6% by mass of linear saturated alcohol having 16 to 22 carbon atoms. (C) One or more compounds selected from monofatty acid glycerol esters and difatty acid sorbitan esters, in which the constituent fatty acids have 16 to 22 carbon atoms, in an amount of 0.3% to 12% by mass. (D) M calculated from the chromatograph obtained by gel permeation chromatography measurement Ｈ and M Ｌ Polypropylene glycol or a lower alkyl ether having 1 to 6 carbon atoms, wherein the average number of added oxypropylene groups satisfying the relationship in formula (1) is 50 or more and 150 or less, 0.05% to 10% by mass. [Math 1] (In equation (1), let L be the length of the perpendicular from the maximum point K on the chromatogram where the refractive index intensity is maximum to the baseline B. Of the two points on the chromatogram where the refractive index intensity is L / 2, let O be the one with the earlier elution time and Q be the one with the later elution time. Let P be the intersection of the line G connecting points O and Q and the perpendicular drawn from the maximum point K to the baseline. Then, let M be the distance between point O and the intersection point P.) Ｈ Let M be the distance between point Q and intersection point P. Ｌ (Assume) (E) Basic amino acids: 0.01% by mass or more, 1.5% by mass or less

2. Furthermore, the oil-in-water emulsion skin cosmetic according to claim 1, further comprising a nonionic surfactant of component (F) HLB 10 to 16 in both the aqueous and oil phases.

3. The oil-in-water emulsion skin cosmetic according to claim 2, comprising component (F) a nonionic surfactant with HLB 10 to 16 in an amount of 0.01% to 1.5% by mass on the aqueous phase side and 0.01% to 1.5% by mass on the oil phase side.

4. Furthermore, the oil-in-water emulsion skin cosmetic according to claim 1 or 2, further containing component (G) a trivalent or greater polyol with a molecular weight of 500 or less.

5. Furthermore, the oil-in-water emulsion skin cosmetic according to claim 4, further comprising one or more selected components (H) glycols with a number average molecular weight of 2000 or less and (I) liquid hydrocarbon oils.

6. The oil-in-water emulsion skin cosmetic according to claim 1 or 2, wherein the chromatogram of component (D), expressed by the refractive index intensity and elution time obtained using a differential refractometer in gel permeation chromatography, is asymmetric, and the asymmetric value As of the peak of the chromatogram, determined as shown below, satisfies the relationship between the following formulas (2) and (3). [Math 2] (In equation (2), of the two points on the chromatogram where the refractive index intensity is L / 20, let R be the point with the earlier elution time, and let S be the point with the later elution time. Let T be the intersection of the line H connecting points R and S and the perpendicular line drawn from the maximum point K to the baseline B. Let W1 / 2 be the distance between point R and intersection T, and W5% be the distance between point R and point S.)

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