Method for producing an emulsified composition using a household stirrer and kit for preparing an emulsified composition

Abstract

To provide a technique that can produce an emulsion composition that causes no separation between an oil phase or an aqueous phase even with weak agitation force.SOLUTION: A method for producing an emulsion composition includes the step of emulsifying a water-soluble copolymer having at least one constitutional unit (a) induced from a specific hydrophobic monomer and at least one constitutional unit (b) induced from a hydrophilic monomer as essential constitutional units, an oil phase component, and an aqueous phase component with weak agitation force.SELECTED DRAWING: Figure 1

Description

Technical Field

[0004] , , ,

[0001] The present invention relates to a method for producing an emulsified composition and a kit for producing an emulsified composition.

Background Art

[0002] In recent years, there has been a focus on so-called DIY cosmetics, where consumers themselves mix raw materials selected according to their skin type and preferences to make homemade cosmetics. For the purpose of preparing homemade emulsified cosmetics at home, products in the category of instant emulsifying waxes containing emulsifiers are also sold. Patent Document 1 discloses a cosmetic production kit for preparing cosmetics at home. Patent Document 2 discloses a preparation kit for a preparation containing a stirring device, two vial bottles pre-filled with liquid, and a third vial bottle used for mixing them, and it is disclosed that it can also be applied to the preparation of cosmetics.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] [[ID=四十]] [[ID=四十一]]When preparing an emulsified composition industrially, an industrial emulsifying device having a strong stirring force is used. On the other hand, at home, the above-mentioned industrial emulsifying device cannot be used, and a household stirrer with poor stirring force such as a hand blender, a tabletop mixer, or a milk frother is used. [[ID=四十二]] [[ID=四十三]]However, with a household stirrer having poor stirring force, it is difficult to produce an emulsified composition without separation of the oil phase and the water phase, and furthermore, there are significant limitations on the type of oil phase components and the ratio of the water phase to the oil phase. [[ID=四十四]]

[0005] In view of the above-mentioned problems, the problem that the present invention aims to solve is to provide a technology that can produce an emulsified composition without separation of the oil phase or aqueous phase, even with a weak stirring force. [Means for solving the problem]

[0006] The present invention, which solves the above problems, is a method for producing an emulsified composition, comprising the step of emulsifying an oil phase component and an aqueous phase component using a household stirrer, having as essential components one or more constituent units (a) derived from a hydrophobic monomer represented by the following general formula (I), (II), or (III) and one or more constituent units (b) derived from a hydrophilic monomer.

[0007] General formula (I) [ka] (I)

[0008] In general formula (I), R1 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R2 represents a branched hydrocarbon group having 13 to 30 carbon atoms that does not have a ring structure, or a hydrocarbon group having 6 to 12 carbon atoms that has two or more branches and does not have a ring structure.

[0009] General formula (II) [ka] (II)

[0010] In general formula (II), R3 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R4 and R5 may be the same or different, representing a branched, non-ring structured acyl group having 6 to 22 carbon atoms. X represents a group obtained by removing an OH group from a trivalent alcohol.

[0011] General formula (III) [ka] (III)

[0012] In general formula (III), R6 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R7, R8, and R9 may be the same or different, representing a branched acyl group having 6 to 22 carbon atoms that does not contain a ring structure. Y represents a group obtained by removing an OH group from a tetravalent alcohol.

[0013] Because the present invention uses the water-soluble copolymer as an emulsifier, an emulsified composition can be prepared without separation of the oil phase and the aqueous phase, even with weak stirring using a household stirrer.

[0014] In a preferred embodiment of the present invention, the household stirring device is selected from a hand blender, a handheld milk frother, a tabletop mixer, a tabletop food processor, and an electric whisk. Even when using a stirrer like those used in food preparation at home, the present invention makes it possible to prepare an emulsified composition without separation of the oil phase and the aqueous phase.

[0015] In a preferred embodiment of the present invention, the weight of the household agitator is 10 kg or less. Even when using an extremely lightweight stirrer, such as those used in food preparation at home, the present invention makes it possible to prepare an emulsified composition without separation of the oil phase and the aqueous phase.

[0016] The present invention also relates to a method for producing an emulsified composition, characterized by comprising the step of emulsifying a water-soluble copolymer having one or more constituent units (a) derived from a hydrophobic monomer represented by the above general formula (I), (II), or (III) and one or more constituent units (b) derived from a hydrophilic monomer as essential constituent units, an oil phase component, and an aqueous phase component by stirring with a stirring force that satisfies the conditions defined in Definition A below.

[0017] [Definition A] When preparing an aqueous solution by mixing 2 parts by mass of a polyoxyethylene ester ether type nonionic surfactant or 0.3 parts by mass of an acrylic acid-methacrylic acid copolymer as an emulsifier, 12 parts by mass of a solution containing 1,3-butylene glycol and glycerin in a ratio of 1:1, and the balance being water at room temperature, and then stirring 65 parts by mass of an oil agent selected from the following Group A and the above aqueous solution at room temperature to prepare 100 parts by mass of an emulsified composition, a stirring force such that not all of the oil agent can be dispersed as emulsion droplets. (A) Squalane, mineral oil, isostearic acid, oleic acid, linoleic acid, linolenic acid, glyceryl tri(caprylate / caprate), triethylhexanoin, olive fruit oil, polydimethylsiloxane, cyclopentasiloxane (However, when selecting a polyoxyethylene ester ether type nonionic surfactant as the emulsifier, mineral oil, triethylhexanoin and olive fruit oil are not selected from Group A-2)

[0018] According to the present invention, even with the stirring force defined in Definition A above, an emulsified composition without separation of the oil phase and the water phase can be produced.

[0019] In a preferred form of the present invention, the stirring force further satisfies the conditions defined in Definition B below. [Definition B] When preparing an aqueous solution by mixing 2 parts by mass of a polyoxyethylene ester ether type nonionic surfactant, 12 parts by mass of a solution containing 1,3-butylene glycol and glycerin in a ratio of 1:1, and 21 parts by mass of water at room temperature, and then stirring 65 parts by mass of an oil agent selected from mineral oil, triethylhexanoin and olive fruit oil and the above aqueous solution at room temperature to prepare 100 parts by mass of an emulsified composition, a stirring force such that all of the oil agent can be dispersed as emulsion droplets.

[0020] By performing emulsification with the stirring force defined in Definition B above, a more stable emulsified composition without phase separation can be produced. [[ID=​In a preferred embodiment of the present invention, the emulsification step is performed using a stirrer that satisfies the conditions defined by the following definition C. [Definition C] When 2% by mass of the water-soluble copolymer, 88% by mass of water, and 10% by mass of squalane are stirred at room temperature, the proportion of squalane that cannot be dispersed as an emulsion droplet can be less than 1% by mass.

[0022] By using a stirrer as defined in definition C, an emulsified composition without separation can be produced.

[0023] In a preferred embodiment of the present invention, the emulsification step is performed such that the amount of phase components that cannot be dispersed as a dispersed phase is less than 1% by mass. By using the aforementioned water-soluble copolymer, an emulsified composition without separation can be produced in this manner.

[0024] In a preferred embodiment of the present invention, the emulsification step is performed using a stirrer that satisfies the conditions defined by the following definition D. [Definition D] When 2% by mass of the aforementioned water-soluble copolymer, 88% by mass of water, and 10% by mass of squalane are stirred at room temperature, the median diameter of the emulsion droplets can be made 30 μm or less.

[0025] By using a stirrer as defined in definition D, a more stable emulsified composition can be produced.

[0026] In a preferred embodiment of the present invention, the emulsification step is performed such that the median diameter of the emulsion droplets is 30 μm or less. By using the aforementioned water-soluble copolymer, an emulsified composition having emulsified droplets with a small median diameter can be produced.

[0027] In a preferred embodiment of the present invention, the emulsification step is performed using a stirrer that satisfies the conditions defined by the following definition E. [Definition E] When 1 mL of a 0.5 wt% aqueous solution of Red No. 504 is dropped into 100 g of an aqueous solution of carboxyvinyl polymer having a viscosity of 26,450 mPa·s or more measured under the following conditions, and the mixture is placed in a 200 mL beaker and the position of the stirrer is fixed with a clamp and continuously stirred at 20°C for 5 minutes, the entire mixture cannot be uniformly dyed. [Conditions] Equipment used: B-type viscometer (manufactured by Shibaura System Co., Ltd.) Temperature: 20°C Rotation speed: 12 rpm Rotor: No. 4 Time: 60 sec

[0028] In a preferred embodiment of the present invention, there is provided a step of determining the blending amount of the oil agent and the amount of the thickener so that the blending amount x (mass%) of the oil agent and the viscosity y (mPa·s) of the emulsion composition satisfy the following relational expression (1) and also satisfy relational expression (2) or (3). [Relational expression] y ≦ -2600x + 186000 (10 ≦ x ≦ 60) (1) y ≧ -120x + 4133 (10 ≦ x ≦ 30) (2) y ≧ 140x - 3400 (30 < x ≦ 60) (3)

[0029] The emulsion composition prepared so as to satisfy the above relational expression is excellent in emulsion stability.

[0030] In a preferred embodiment of the present invention, there is provided a step of determining the blending amount of the oil agent and the concentration of the carboxyvinyl polymer so that the blending amount x (mass%) of the oil agent and the concentration y (mass%) of the carboxyvinyl polymer satisfy the following relational expressions (32), (33), or (34) and also satisfy relational expressions (35), (36), or (37). [Relational expression] y ≦ -0.0725x + 2.525 (10 ≦ x ≦ 30) ··· Relational expression (32) y ≦ -0.02x + 0.95 (30 < x ≦ 40) ··· Relational expression (3) y ≦ -0.0056x + 0.374 (40 < x ≦ 60) ··· Relational expression (34) y ≧ -0.0024x + 0.104 (10 ≦ x ≦ 30) ··· Relational expression (35) y ≧ -0.032 (30 < x ≦ 50) ··· Relational expression (36) y ≧ -0.001x + 0.082 (50 < x ≦ 60) ··· Relational expression (37)

[0031] The emulsified composition prepared to satisfy the above relational expressions is excellent in emulsion stability.

[0032] In a preferred form of the present invention, emulsification is carried out at 5°C to 40°C in the step of emulsifying. By using the water-soluble copolymer, an emulsified composition without separation can be produced even at room temperature. Therefore, it is possible to easily produce an emulsified composition even in the home.

[0033] In the present invention, the hydrophilic monomer is one or more hydrophilic monomers selected from the group consisting of a polymerizable carboxylic acid, a hydrophilic monomer represented by the following general formula (IV), a hydrophilic monomer represented by the following general formula (VI), a hydrophilic monomer represented by the following general formula (VII), and a hydrophilic monomer represented by the following general formula (VIII).

[0034] General formula (IV)

Chemical formula

[0035] In general formula (IV), R10 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R11 represents an alkylene group having 2 to 4 carbon atoms which may have a hydroxyl group, and R12 represents a hydrogen atom, an aromatic hydrocarbon group having 6 to 10 carbon atoms, an aliphatic hydrocarbon group having 1 to 14 carbon atoms, or an acyl group having 1 to 12 carbon atoms. n represents an integer of 6 to 40.

[0036] General formula (VI)

Chemical formula

[0037] In general formula (VI), R15 represents a hydrogen atom or a methyl group.

[0038] General formula (VII) [ka] (VII)

[0039] In general formula (VII), R16 represents a hydrogen atom or a methyl group, GO- represents a group obtained by removing a hydrogen atom from the hydroxyl group at position 1 of a reducing sugar, m represents 2 or 3, and l represents an integer from 1 to 5.

[0040] General formula (VIII) [ka] (VIII)

[0041] In general formula (VIII), R17 represents a hydrogen atom or a methyl group, and R18 represents an amino acid residue, a polyamine residue, or an amino alcohol residue. Q represents an oxygen atom or a group represented by NH.

[0042] In a preferred embodiment of the present invention, the hydrophobic monomer is a hydrophobic monomer represented by the general formula (II), and the water-soluble monomer is a hydrophilic monomer represented by the general formula (IV).

[0043] The present invention also relates to an emulsified composition produced by the manufacturing method described above. The emulsified composition of the present invention exhibits good quality with no separation between the oil phase and the aqueous phase.

[0044] The present invention also relates to a kit for preparing an emulsified composition, characterized by comprising: a packaging container filled with a water-soluble copolymer or an aqueous dispersion thereof having as essential constituent units one or more constituent units (a) derived from a hydrophobic monomer represented by the above general formula (I), (II), or (III); a packaging container filled with an oil phase component; and a packaging container filled with an aqueous phase component. According to the emulsified composition preparation kit of the present invention, consumers can easily prepare emulsified compositions at home.

[0045] In a preferred embodiment of the present invention, the kit further includes a stirrer, more preferably a household stirrer. Since the kit includes a stirrer, consumers can easily prepare the emulsified composition at home without having to prepare their own stirrer.

[0046] In a preferred embodiment of the present invention, the stirring force of the agitator satisfies the conditions defined by definition A below. [Definition A] A stirring force is required to prepare an aqueous solution by mixing 2 parts by mass of a polyoxyethylene ester ether type nonionic surfactant or 0.3 parts by mass of an acrylic acid / methacrylic acid copolymer as an emulsifier, 12 parts by mass of a solution containing 1,3-butylene glycol and glycerin in a 1:1 ratio, and the remainder of water at room temperature. When this aqueous solution and 65 parts by mass of an oil selected from group A below are stirred at room temperature to prepare 100 parts by mass of an emulsified composition, the stirring force is required to prevent all of the oil from being dispersed as emulsified droplets. (A) Squalane, Mineral Oil, Isostearic Acid, Oleic Acid, Linoleic Acid, Linolenic Acid, Caprylic / Capric Triglyceride, Triethylhexanoin, Olive Fruit Oil, Polydimethylsiloxane, Cyclopentasiloxane (However, when selecting a polyoxyethylene ester ether type nonionic surfactant as an emulsifier, mineral oil, triethylhexanoin, and olive fruit oil from Group A are not selected.)

[0047] In a preferred embodiment of the present invention, the stirring force further satisfies the conditions defined by definition B below. [Definition B] A stirring force capable of dispersing all of the oil as emulsion droplets when an aqueous solution is prepared by mixing 2 parts by mass of a polyoxyethylene ester ether type nonionic surfactant, 12 parts by mass of a solution containing 1,3-butylene glycol and glycerin in a 1:1 ratio, and 21 parts by mass of water at room temperature, and then stirring this aqueous solution with 65 parts by mass of an oil selected from mineral oil, triethylhexanoin, and olive fruit oil at room temperature to prepare an emulsion composition of 100 parts by mass.

[0048] In a preferred embodiment of the present invention, the agitator satisfies the conditions defined by the following definition C. [Definition C] When 2% by mass of the water-soluble copolymer, 88% by mass of water, and 10% by mass of squalane are stirred at room temperature, the proportion of squalane that cannot be dispersed as an emulsion droplet can be less than 1% by mass.

[0049] In a preferred embodiment of the present invention, the agitator satisfies the conditions defined by the following definition D. [Definition D] When 2% by mass of the aforementioned water-soluble copolymer, 88% by mass of water, and 10% by mass of squalane are stirred at room temperature, the median diameter of the emulsion droplets can be made 30 μm or less.

[0050] In a preferred embodiment of the present invention, the agitator satisfies the conditions defined by the following definition E. [Definition E] When a mixture of 100g of a carboxyvinyl polymer aqueous solution with a viscosity of 26450 mPa·s or higher, measured under the following conditions, and 1 mL of a 0.5 wt% Red No. 504 aqueous solution is added dropwise, and this mixture is placed in a 200 mL beaker, and the stirrer is fixed in place with a clamp, and the mixture is continuously stirred at 20°C for 5 minutes, the entire mixture cannot be uniformly stained. [conditions] Equipment used: Type B viscometer (manufactured by Shibaura Systems Co., Ltd.) Temperature: 20℃ Rotation speed: 12 rpm Rotor: No. 4 Time: 60sec [Effects of the Invention]

[0051] According to the present invention, an emulsified composition without separation of the oil phase and aqueous phase can be easily prepared using a household stirrer. [Brief explanation of the drawing]

[0052] [Figure 1] The image shows a side view of the composition after stirring, using squalane as the oil agent and (a) POE surfactant, (b) AAMA polymer, and (c) water-soluble copolymer as emulsifiers. [Figure 2] The image shows a photograph of the liquid surface of a composition after stirring, using squalane as the oil agent and (a) POE surfactant, (b) AAMA polymer, and (c) water-soluble copolymer as emulsifiers. In the photograph, the black arrows indicate the separated oil agent. [Figure 3] Microscopic images of emulsion droplets in an emulsion composition of a water-soluble copolymer, squalane, and water are shown. [Figure 4] This shows the evaluation of the surface condition and microscopic images of emulsified compositions prepared using a water-soluble copolymer or AAMA polymer as an emulsifier, either under heating or without heating, after 1 month of storage (5°C), 1 month of storage (20°C), and 1 month of storage (50°C). [Figure 5] This is a histogram of the particle size of oil droplets in the emulsified composition prepared in Test Example 4, immediately after preparation and after storage for one month. [Figure 6] This graph shows the results of static viscosity measurements of the emulsified composition prepared in Test Example 4, both immediately after preparation and after storage for one month. [Figure 7] This graph shows the viscosity of the emulsified composition prepared in Test Example 4 at a shear rate of 1 / s, both immediately after preparation and after storage for one month. [Figure 8] This figure plots the amount of oil (x, by mass%) and the viscosity (y, mPa·s) of each emulsion composition prepared in Test Example 5. [Figure 9] Figure 8 shows the plots of each relationship. [Figure 10]This figure plots the amount of oil (x by mass%) and the concentration (mass%) of carboxyvinyl polymer for each emulsified composition prepared in Test Example 5. [Figure 11] Figure 10 shows the plots of each relationship. [Modes for carrying out the invention]

[0053] The distinguishing feature of the present invention is the use of a water-soluble copolymer having a constituent unit (a) derived from a hydrophobic monomer and a constituent unit (b) derived from a hydrophilic monomer. <1> This section will explain hydrophobic monomers, hydrophilic monomers, and water-soluble copolymers which are copolymers thereof.

[0054] <1> Water-soluble copolymer (1) Hydrophobic monomer In the present invention, a water-soluble copolymer is used that contains one or more constituent units derived from the hydrophobic monomer represented by the general formula (I), (II), or (III) (hereinafter sometimes simply referred to as "constituent unit I," etc.) as essential constituent units. In this invention, "constituent unit derived from monomer" refers to a constituent unit formed when the carbon-carbon unsaturated bond of the corresponding monomer is cleaved by a polymerization reaction. The following describes hydrophobic monomers represented by general formulas (I), (II), or (III).

[0055] (1-1) Hydrophobic monomer represented by general formula (I) In the general formula (I) above, R1 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R2 represents a branched hydrocarbon group having 13 to 30 carbon atoms that does not have a ring structure, or a hydrocarbon group having 6 to 12 carbon atoms that does not have a ring structure and has two or more branches. Examples of alkyl groups represented by R1 include methyl, ethyl, propyl, isopropyl, and cyclopropyl groups. In the present invention, R1 is preferably a hydrogen atom or a methyl group.

[0056] Furthermore, examples of branched hydrocarbon groups that do not contain a ring structure with 13 to 30 carbon atoms represented by R2 include 1-methyldodecanyl group, 11-methyldodecanyl group, 3-ethylundecanyl group, 3-ethyl-4,5,6-trimethyloctyl group, 1-methyltridecanyl group, 1-hexyloctyl group, 2-butyldecanyl group, 2-hexyloctyl group, 4-ethyl-1-isobutyloctyl group, 1-methylpentadecanyl group, 2-hexyldecanyl group, 2-octyldecanyl group, 2-hexyldodecanyl group, 16-methylheptadecanyl group, 9-methylheptadecanyl group, 7-methyl-2-(3-methylhexyl)decanyl group, 3,7,11,15-tetra-methylhexadecanyl group, 2-octyldodecanyl group, 2-decyltetradecanyl group, and 2-dodecylhexadecanyl group.

[0057] Furthermore, examples of hydrocarbon groups with 6 to 12 carbon atoms that do not contain a ring structure and have two or more branches, represented by R2, include 2,2-dimethylbutyl group, 2,3-dimethylbutyl group, 3,3-dimethylbutyl group, 1,3-dimethylbutyl group, 1,2,2-trimethylpropyl group, 1,1-dimethylpentanyl group, 1-isopropylbutyl group, 1-isopropyl-2-methylpropyl group, 1,1-diethylpropyl group, 1-ethyl-1-isopropylpropyl group, 2-ethyl-4-methylpentyl group, 1-propyl-2,2-dimethylpropyl group, 1,1,2-trimethylpentyl group, 1-isopropyl-3-methylbutyl group, 1,2-dimethyl-1-ethylbutyl group, 1,3-dimethyl-1-ethylbutyl group, 1-ethyl-1-isopropylpropyl group, and 1,1 Examples include the -dimethylhexyl group, 1-methyl-1-ethylpentyl group, 1-methyl-1-propylbutyl group, 1,4-dimethylhexyl group, 1-ethyl-3-methylpentyl group, 1,5-dimethylhexyl group, 1-ethyl-6-methylheptyl group, 1,1,3,3-tetramethylbutyl group, 1,2-dimethyl-1-isopropylpropyl group, 3-methyl-1-(2,2-dimethylethyl)butyl group, 1-isopropylhexyl group, 3,5,5-trimethylhexyl group, 2-isopropyl-5-methylhexyl group, 1,5-dimethyl-1-ethylhexyl group, 3,7-dimethyloctyl group, 2,4,5-trimethylheptyl group, 2,4,6-trimethylheptyl group, and 3,5-dimethyl-1-(2,2-dimethylethyl)hexyl group.

[0058] (1-2) Hydrophobic monomers represented by general formula (II) or (III) In the general formulas (II) and (III) above, R3 and R6 represent hydrogen atoms or alkyl groups having 1 to 3 carbon atoms, and R4, R5, R7, R8, and R9 may be the same or different, and represent branched acyl groups having 6 to 22 carbon atoms that do not contain a ring structure. X represents a group obtained by removing an OH group from a trivalent alcohol.

[0059] Examples of alkyl groups represented by R3 and R6 include methyl groups, ethyl groups, propyl groups, isopropyl groups, and cyclopropyl groups. In the present invention, R3 is preferably a hydrogen atom or a methyl group.

[0060] Furthermore, branched acyl groups having 6 to 22 carbon atoms that do not contain the ring structure represented by R4, R5, R7, R8, and R9 include 2-methylpentanoyl, 3-methylpentanoyl, 4-methylpentanoyl, 2-ethylbutanoyl, 2-ethylbutanoyl, 2,2-dimethylbutanoyl, 3,3-dimethylbutanoyl, 2-methylhexanoyl, 4-methylhexanoyl, 5-methylhexanoyl, 2,2-dimethylpentanoyl, 4,4-dimethylpentanoyl, 2-methylheptanoyl, and 2-ethylhexanoyl. Syl group, 2-propylpentanoyl group, 2,2-dimethylhexanoyl group, 2,2,3-trimethylpentanoyl group, 2-methyloctanoyl group, 3,3,5-trimethylhexanoyl group, 2-methylnonanoyl group, 4-methylnonanoyl group, 8-methylnonanoyl group, 4-ethyloctanoyl group, 2-ethyloctanoyl group, 2-butylhexanoyl group, 2-tert-butylhexanoyl group, 2,2-diethylhexanoyl group, 2,2-dimethyloctanoyl group, 3,7-dimethyloctanoyl group, neodecanoyl group, 7-methyl Rudecanoyl group, 2-methyl-2-ethyloctanoyl group, 2-methylundecanoyl group, 10-methylundecanoyl group, 2,2-dimethyldecanoyl group, 2-ethyldecanoyl group, 2-butyloctanoyl group, diethyloctanoyl group, 2-tert-butyl-2,2,4-trimethylpentanoyl group, 10-methyldodecanoyl group, 3-methyldodecanoyl group, 4-methyldodecanoyl group, 11-methyldodecanoyl group, 10-ethylundecanoyl group, 12-methyltridecanoyl group, 2-butyldecanoyl group, 2-hexyl Examples include octanoyl group, 2-butyl-2-ethyloctanoyl group, 12-methyltetradecanoyl group, 14-methylpentadecanoyl group, 2-butyldodecanoyl group, 2-hexyldecanoyl group, 16-methylheptadecanoyl group, 2,2-dimethylhexanoyl group, 2-butylhexadecanoyl group, 2-hexyldodecanoyl group, 2,4,10,14-tetramethylpentanoyl group, 18-methylnonadecanoyl group, 3,7,11,15-tetramethylhexadecanoyl group, and 19-methyleicosaenoyl group.

[0061] Furthermore, in preferred embodiments of the present invention, in general formulas (II) and (III), R4, R5, R7, R8, and R9 may be the same or different, and are branched acyl groups having 10 to 22 carbon atoms that do not contain a ring structure, or acyl groups having 6 to 9 carbon atoms that have two or more branches and do not contain a ring structure.

[0062] In this preferred embodiment, the branched acyl groups having 10 to 22 carbon atoms that do not contain a ring structure, represented by R4, R5, R7, R8, and R9, include: 2-methylnonanoyl group, 4-methylnonanoyl group, 8-methylnonanoyl group, 4-ethyloctanoyl group, 2-ethyloctanoyl group, 2-butylhexanoyl group, 2-tert-butylhexanoyl group, 2,2-diethylhexanoyl group, 2,2-dimethyloctanoyl group, 3,7-dimethyloctanoyl group, neodecanoyl group, 7-methyldecanoyl group, 2-methyl-2-ethyloctanoyl group, 2-methylundecanoyl group, 10-methylundecanoyl group, 2,2-dimethyldecanoyl group, 2-ethyldecanoyl group, 2-butyloctanoyl group, diethyloctanoyl group, and 2-tert-butyl-2,2,4 Methylpentanoyl group, 10-methyldodecanoyl group, 3-methyldodecanoyl group, 4-methyldodecanoyl group, 11-methyldodecanoyl group, 10-ethylundecanoyl group, 12-methyltridecanoyl group, 2-butyldecanoyl group, 2-hexyloctanoyl group, 2-butyl-2-ethyloctanoyl group, 12-methyltetradecanoyl group, 14-methylpentadecanoyl group, 2-butyl Examples include chyldodecanoyl group, 2-hexyldecanoyl group, 16-methylheptadecanoyl group, 2,2-dimethylhexanoyl group, 2-butylhexadecanoyl group, 2-hexyldodecanoyl group, 2,4,10,14-tetramethylpentanoyl group, 18-methylnonadecanoyl group, 3,7,11,15-tetramethylhexadecanoyl group, and 19-methyleicosanoyl group.

[0063] Furthermore, examples of acyl groups having 6 to 9 carbon atoms, having two or more branches and not containing a ring structure, represented by R4, R5, R7, R8, and R9 in preferred embodiments include 2,2-dimethylbutanoyl group, 3,3-dimethylbutanoyl group, 2,2-dimethylpentanoyl group, 4,4-dimethylpentanoyl group, 2,2-dimethylhexanoyl group, 2,2,3-trimethylpentanoyl group, and 3,5,5-trimethylhexanoyl group.

[0064] The group derived from a trihydric alcohol represented by X in general formula (II) is not particularly limited as long as it is a group obtained by removing an OH group from a trihydric alcohol, but preferred examples include groups obtained by removing an OH group from a trihydric alcohol selected from the group consisting of glycerin, trimethylolpropane, and trimethylolethane.

[0065] Furthermore, the group derived from the tetrahydric alcohol represented by Y in general formula (III) is not particularly limited as long as it is a group obtained by removing the OH group from the tetrahydric alcohol, but preferred examples include groups obtained by removing the OH group from a tetrahydric alcohol selected from the group consisting of diglycerin, pentaerythritol, erythritol, D-threitol, and L-threitol.

[0066] In the present invention, it is particularly preferable to use a water-soluble copolymer containing constituent unit II. Furthermore, in a more preferred embodiment of the present invention, the hydrophobic monomer represented by general formula (II) is the hydrophobic monomer represented by the following general formula (V).

[0067] General formula (V) [ka] (V) (In general formula (V), R13 and R14 may be the same or different, and represent branched acyl groups with 16 to 22 carbon atoms that do not contain a ring structure. Z represents a group obtained by removing an OH group from a trivalent alcohol.)

[0068] The number of carbon atoms in the acyl groups R13 and R14 of general formula (V) is 12 to 22, more preferably 14 to 20, and even more preferably 16 to 20. Furthermore, the number of carbon atoms in the main chain of the acyl groups R13 and R14 of general formula (V) is preferably 9 to 21, more preferably 12 to 20, and even more preferably 16 to 18. Furthermore, the number of branches in the acyl groups R13 and R14 of general formula (V) is preferably 1 to 3, more preferably 1 or 2, and even more preferably 1. Furthermore, in the acyl groups R13 and R14 of general formula (V), it is preferable that the position number of the carbon atom in the main chain to which the branched chain is attached is larger. Specifically, it is preferable that the branched chain is attached to the carbon atom at the end of the main chain, preferably the 1st to 3rd carbon, more preferably the 1st or 2nd carbon, and even more preferably the 1st carbon.

[0069] Specific examples of R13 and R14 include 10-methylundecanoyl group, 10-methyldodecanoyl group, 11-methyldodecanoyl group, 10-ethylundecanoyl group, 12-methyltridecanoyl group, 12-methyltetradecanoyl group, 14-methylpentadecanoyl group, 16-methylheptadecanoyl group, 2,4,10,14-tetramethylpentanoyl group, 18-methylnonadecanoyl group, 3,7,11,15-tetramethylhexadecanoyl group, 19-methyleicosaenoyl group, and the like.

[0070] The group derived from a trihydric alcohol represented by Z in general formula (V) is not particularly limited as long as it is a group obtained by removing an OH group from a trihydric alcohol, but preferred examples include groups obtained by removing an OH group from a trihydric alcohol selected from the group consisting of glycerin, trimethylolpropane, and trimethylolethane.

[0071] (2) Hydrophilic monomers As hydrophilic monomers in the present invention, polymerizable carboxylic acids and compounds represented by the following general formulas (IV), (VI), (VII), and (VIII) can be used.

[0072] (2-1) Polymerizable carboxylic acids In the present invention, examples of polymerizable carboxylic acids or their salts include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid and their sodium salts, potassium salts, ammonium salts, and amine salts. Among these, acrylic acid, methacrylic acid and their salts are particularly preferred due to their high polymerizability. When introducing structural units derived from polymerizable carboxylic acid salts into the water-soluble copolymer of the present invention, the polymerizable carboxylic acid may be prepared as a salt beforehand and the polymerization reaction may be carried out, or the structural units derived from the polymerizable carboxylic acid may be converted into a water-soluble copolymer by the polymerization reaction, and then neutralized with a base to form a salt.

[0073] (2-2) Hydrophilic monomers represented by general formula (IV) In the general formula (IV) above, R10 represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, R11 represents an alkylene group having 2 to 4 carbon atoms which may have a hydroxyl group, and R12 represents a hydrogen atom, an aromatic hydrocarbon group having 6 to 10 carbon atoms, an aliphatic hydrocarbon group having 1 to 14 carbon atoms, or an acyl group having 1 to 12 carbon atoms. n represents an integer from 6 to 40.

[0074] Examples of alkyl groups represented by R10 in the general formula (IV) above include methyl, ethyl, propyl, isopropyl, and cyclopropyl groups. In the present invention, R10 is preferably a hydrogen atom or a methyl group.

[0075] Furthermore, examples of alkylene groups represented by R11 include ethylene, propylene, isopropylene, 2-hydroxypropylene, 1-hydroxy-2-methylethylene, and 2-hydroxy-1-methylethylene. Of these, ethylene or propylene is preferred, and ethylene is more preferred.

[0076] Furthermore, among the groups represented by R12, examples of aromatic groups having 6 to 10 carbon atoms include phenyl, benzyl, methylphenyl, and ethylphenyl groups; suitable examples of aliphatic hydrocarbon groups having 1 to 14 carbon atoms include methyl, ethyl, butyl, tert-butyl, hexyl, cyclohexyl, octyl, 2-ethylhexyl, and lauryl groups; suitable examples of acyl groups having 1 to 12 carbon atoms include formyl, acetyl, propionyl, butyryl, isobutyryl, valeryl, and lauroyl groups. Of these, the group represented by R5 is preferably an aliphatic hydrocarbon group having 1 to 14 carbon atoms, and more preferably an alkyl group having 1 to 12 carbon atoms.

[0077] Furthermore, in general formula (IV), n is a numerical value in the range of 6 to 40.

[0078] Specific examples of monomers represented by the general formula (IV) in which R11 is a propylene group include polypropylene glycol (9) monoacrylate, polypropylene glycol (13) monoacrylate, polypropylene glycol (9) monomethacrylate, and polypropylene glycol (13) monomethacrylate. The number in parentheses represents N. Many of these polymers are available commercially. Examples of these commercially available products include the trade names "Bremmer" AP-400, AP-550, AP-800, PP-500, and PP-800 (all manufactured by Nippon Oil & Fats Co., Ltd.).

[0079] Among the monomers represented by the general formula (IV) above, specific examples of monomers in which R11 is an ethylene group include polyethylene glycol (10) monoacrylate, polyethylene glycol (8) monomethacrylate, polyethylene glycol (23) monoacrylate, polyethylene glycol (23) monomethacrylate, methoxypolyethylene glycol (9) acrylate, methoxypolyethylene glycol (9) methacrylate, methoxypolyethylene glycol (23) methacrylate, oleyloxypolyethylene glycol (18) methacrylate, lauroxypolyethylene glycol (18) acrylate, lauroyloxypolyethylene glycol (10) methacrylate, stearoxypolyethylene glycol (30) monomethacrylate, and the like.

[0080] The hydrophilic monomers mentioned above can be obtained in high yield by esterification reactions of the corresponding polyethylene glycol, polyethylene glycol monoether, or polyethylene glycol monoester with acrylic acid or methacrylic acid chloride or anhydride. Furthermore, many commercially available products already exist, and it is also possible to utilize such commercial products. Examples of such commercial products include those with trade names such as Bremmer, AE-400, PE-350, AME-400, PME-400, PME-1000, ALE-800, and PSE-1300 (all manufactured by Nippon Oil & Fats Co., Ltd.).

[0081] (2-3) Hydrophilic monomers represented by general formula (VI) In the present invention, a hydrophilic monomer represented by the following general formula (VI) may be used as the hydrophilic monomer.

[0082] (General formula VI) [ka] (VI) (In general formula (VI), R15 represents a hydrogen atom or a methyl group.)

[0083] Specific examples of hydrophilic monomers represented by the general formula (VI) include 2-acryloyloxyethyl phosphorylcholine (APC) and 2-methacryloyloxyethyl phosphorylcholine (MPC). These monomers can be synthesized, for example, by the following method described in Polymer Journal, Vol. 22, No. 5. <Synthesis method> 2-bromoethyl phosphoryl dichloride is reacted with 2-hydroxyethyl methacrylate or 2-hydroxyethyl acrylate to obtain 2-methacryloyloxyethyl-2'-bromoethyl phosphate or 2-acryloyloxyethyl-2'-bromoethyl phosphate, and then these compounds are reacted with triethylamine in methanol.

[0084] (2-4) Hydrophilic monomers represented by general formula (VII) In the present invention, a hydrophilic monomer represented by the following general formula (VII) may be used as the hydrophilic monomer.

[0085] General formula (VII) [ka] (VII) (In general formula (VII), R16 represents a hydrogen atom or a methyl group, GO- represents a group obtained by removing a hydrogen atom from the hydroxyl group at position 1 of a reducing sugar, m represents 2 or 3, and l represents an integer from 1 to 5.)

[0086] In the hydrophilic monomer represented by general formula (VII), the reducing sugar obtained by removing hydrogen from the hydroxyl group at position 1 of the reducing sugar represented by GO- is specifically one or more selected from the group consisting of monosaccharides such as glucose, mannose, galactose, arabinose, xylose, and ribose; disaccharides such as maltose, lactose, and cellobiose; trisaccharides such as maltotriose; and oligosaccharides such as maltooligosaccharides. Among these, one or more selected from the group consisting of glucose, galactose, arabinose, xylose, ribose, maltose, and lactose cellobiose are preferred, with glucose being particularly preferred. Furthermore, as the monomer represented by general formula (VII), glucosyloxyethyl methacrylate (hereinafter abbreviated as GEMA) or glucosyloxyethyl acrylate (hereinafter abbreviated as GEA) are preferred.

[0087] (2-5) Hydrophilic monomers represented by general formula (VIII) In the present invention, a hydrophilic monomer represented by the following general formula (VIII) may be used as the hydrophilic monomer.

[0088] General formula (VIII) [ka] (VIII) (In general formula (VIII), R17 represents a hydrogen atom or a methyl group, R18 represents an amino acid residue, a polyamine residue, or an amino alcohol residue, and Q represents an oxygen atom or a group represented by NH.)

[0089] In the monomer of general formula (VIII), the amino acid of the amino acid residue represented by R18 is not particularly limited as long as it is a commonly known amino acid, and specific examples include glycine, alanine, glutamine, lysine, and arginine. Among these, the lysine residue is particularly preferred because the resulting water-soluble copolymer exhibits excellent skin barrier restoration effects.

[0090] Furthermore, the polyamine in the polyamine residue represented by R18 refers to an amine having two or more amino groups that may be substituted with alkyl groups within the same molecule. Specifically, examples include diamines, triamines, tetraamines, or amines in which the hydrogen atoms of these amino groups are substituted with alkyl groups. Among these, diamines are preferred because they provide a particularly excellent feel when used in topical skin preparations containing the resulting water-soluble copolymer. Particularly preferred examples include ethylenediamine, 1,4-diamino-n-butane, and 1,6-diamino-n-hexane, due to the ease of obtaining raw materials for synthesis.

[0091] Furthermore, the amino alcohol in the amino alcohol residue represented by R18 refers to a compound having an amino group and an alcoholic hydroxyl group, which may be substituted with an alkyl group within the same molecule. While there are no particular limitations on the amino alcohol itself, as long as it is a commonly known compound, specific examples include ethanolamine and triethylaminoethanol.

[0092] The salts of the monomer represented by general formula (VIII) are not particularly limited, but specific examples include sodium salts, potassium salts, ammonium salts, amine salts, etc., obtained by neutralizing the acid portion with a base, and hydrochloride salts, sulfate salts, nitrate salts, phosphate salts, citrate salts, oxalate salts, carbonate salts, etc., obtained by neutralizing the amino group portion with an acid. When introducing structural units derived from salts of the monomer represented by general formula (VIII) into the water-soluble copolymer of the present invention, the monomer represented by general formula (VIII) may be prepared as a salt beforehand and the polymerization reaction may be carried out, or the structural units derived from the monomer represented by general formula (VIII) may be introduced into the water-soluble copolymer by the polymerization reaction and then neutralized to form a salt.

[0093] Specific examples of monomers represented by general formula (VIII) and their salts include compounds having the following structures and their salts.

[0094] [ka]

[0095]

change

[0096]

change

[0097]

change

[0098]

change

[0099]

change

[0100]

change

[0101]

change

[0102]

change

[0103]

change

[0104]

change

[0105] Hydrophilic monomers represented by general formula (VIII) can be synthesized, for example, by esterification and amidation reactions using (meth)acrylic acid and (meth)acrylic acid chloride, as shown below. [ka] [ka] (In the reaction equation, R17 represents a hydrogen atom or a methyl group, R18 represents an amino acid residue, a polyamine residue, or an amino alcohol residue, and Q represents an oxygen atom or a group represented by NH.)

[0106] As described above, in the present invention, the hydrophilic polymer can be the one specified by general formula (IV), general formula (VI), general formula (VII), and general formula (VIII). In a preferred embodiment of the present invention, the water-soluble copolymer comprises a constituent unit IV derived from the general formula (IV).

[0107] (3) Water-soluble copolymer In the present invention, a water-soluble copolymer having constituent unit II and constituent unit IV can be preferably used. More preferably, a water-soluble copolymer having constituent unit V and constituent unit IV can be used. Among such water-soluble copolymers, (methoxy PEG-23 methacrylate / glyceryl methacrylate diisostearate) copolymer is particularly preferred. By including such a water-soluble copolymer, an emulsifying composition is obtained that is less irritating, less sticky, and has excellent emulsification stability.

[0108] The (Methoxy PEG-23 methacrylate / Glyceryl methacrylate diisostearate) copolymer mainly contains, as a constituent unit (a), a constituent unit (a) derived from a hydrophobic monomer represented by the general formula (V) in which R13 and R14 are 16-methylheptadecanoyl groups. Furthermore, the constituent unit (b) mainly includes a constituent unit (b) derived from a hydrophilic monomer represented by the general formula (IV) in which R10 is a methyl group, R11 is an ethylene group, R12 is a methyl group, and n is 23.

[0109] Generally, highly hydrophobic surfactants are suitable for forming water-in-oil emulsions, while highly hydrophilic surfactants are suitable for forming oil-in-water emulsions. Similarly, in the case of the water-soluble copolymer in the present invention, if the proportion of hydrophobic constituent units (a) is high, it is suitable for forming water-in-oil emulsions, and if the proportion of hydrophilic constituent units (b) is high, it is suitable for forming oil-in-water emulsions. In this way, the emulsion form of the emulsion composition can be adjusted by appropriately adjusting the proportions and ratios of constituent units (a) and (b).

[0110] In the present invention, the proportion of constituent unit (a) to the total constituent units in the water-soluble copolymer is preferably 1 to 50% by mass, more preferably 20 to 50% by mass, and 30 to 40% by mass. By setting the proportion of constituent unit (a) in the water-soluble copolymer to the aforementioned range, it is possible to provide an oil-in-water emulsion composition with a reduced sticky feeling.

[0111] In the present invention, the proportion of constituent unit (b) to the total constituent units in the water-soluble copolymer is preferably 50 to 99% by mass, more preferably 50 to 80% by mass, and 60 to 70% by mass. By setting the proportion of constituent unit (b) in the water-soluble copolymer to the aforementioned range, it is possible to provide an oil-in-water emulsion composition with a reduced sticky feeling.

[0112] In the present invention, the mass ratio of constituent unit (a) to constituent unit (b) constituting the water-soluble copolymer is preferably 10:90 to 50:50, more preferably 20:80 to 50:50, and even more preferably 30:70 to 40:60.

[0113] Furthermore, the molar ratio of constituent unit (a) to constituent unit (b) that constitute the water-soluble copolymer is preferably 15:85 to 62:38, more preferably 29:71 to 62:38, and even more preferably 41:59 to 52:48. By setting the mass ratio and molar ratio of constituent unit (a) and constituent unit (b) in the water-soluble copolymer to the aforementioned range, a water-soluble copolymer with excellent emulsifying power, suitable for forming oil-in-water emulsion compositions, can be obtained.

[0114] In the present invention, the average molecular weight of the water-soluble copolymer is preferably 20,000 to 110,000, more preferably 20,000 to 80,000, more preferably 30,000 to 80,000, more preferably 40,000 to 70,000, even more preferably 50,000 to 70,000, and even more preferably 57,000 to 66,000. In this context, the average molecular weight refers to the weight-average molecular weight of polystyrene, measured by GPC.

[0115] <2> Method for producing an emulsified composition The present invention includes an emulsification step of stirring the above-mentioned water-soluble copolymer, oil phase component, and aqueous phase component to emulsify them. The emulsification step can be carried out using a household stirrer. Here, "household stirrer" refers to a stirrer sold as a household appliance, not a powerful stirrer used for the industrial production of emulsified compositions.

[0116] While there are no particular limitations on the stirring method of a household stirrer, a preferred example is one in which emulsification is performed based on the shear force generated by rotating a blade.

[0117] As household mixers, those used as household cooking appliances are preferred. Preferably, lightweight mixers weighing 10 kg or less, more preferably 8 kg or less, even more preferably 6 kg or less, even more preferably 4 kg or less, and even more preferably 2 kg or less are preferred. Specifically, these include hand blenders, handheld milk frothers, tabletop mixers, tabletop food processors, and electric whisks. These household stirrers have less stirring power compared to emulsifying equipment used in industry. However, in the method for producing the emulsified composition of the present invention, by using the above-mentioned water-soluble copolymer as an emulsifier, it is possible to prepare an emulsified composition without separation of the oil phase and the aqueous phase, even when using such a household stirrer with limited stirring power.

[0118] Furthermore, it is preferable that the stirring force used when emulsifying the water-soluble copolymer, oil phase component, and aqueous phase component in the emulsification process satisfies the conditions defined in definition A below.

[0119] [Definition A] A stirring force is required to prepare an aqueous solution by mixing 2 parts by mass of a polyoxyethylene ester ether type nonionic surfactant or 0.3 parts by mass of an acrylic acid / methacrylic acid copolymer as an emulsifier, 12 parts by mass of a solution containing 1,3-butylene glycol and glycerin in a 1:1 ratio, and the remainder of water at room temperature. When this aqueous solution and 65 parts by mass of an oil selected from group A below are stirred at room temperature to prepare 100 parts by mass of an emulsified composition, the stirring force is required to prevent all of the oil from being dispersed as emulsified droplets. (A) Squalane, Mineral Oil, Isostearic Acid, Oleic Acid, Linoleic Acid, Linolenic Acid, Caprylic / Capric Triglyceride, Triethylhexanoin, Olive Fruit Oil, Polydimethylsiloxane, Cyclopentasiloxane (However, when selecting a polyoxyethylene ester ether type nonionic surfactant as an emulsifier, mineral oil, triethylhexanoin, and olive fruit oil from Group A are not selected.)

[0120] In this invention, even when emulsification is performed by stirring with a weak stirring force as defined in definition A, an emulsified composition without phase separation can be produced.

[0121] Specifically, polyoxyethylene hydrogenated castor oil is an example of a "polyoxyethylene ester ether type nonionic surfactant" in Definition A.

[0122] Furthermore, as a "acrylic acid / methacrylic acid copolymer" in definition A, a specific example is (acrylates / alkyl acrylate (C10-30)) crosspolymer.

[0123] Furthermore, the volume of the mixture of emulsifier, 1,3-butylene glycol and glycerin, water and oil, which is stirred in Definition A, is preferably 10 to 400 ml, and more preferably 30 to 300 ml.

[0124] Furthermore, whether or not "all of the oil is dispersed as emulsified droplets" as defined in Definition A can be determined by checking whether or not the oil has separated into phases and is floating on top. This determination can be made visually. If the oil has separated into phases and is floating, it can be determined that "all of the oil has not been dispersed as emulsified droplets."

[0125] In Definition A, the oils listed in Group A may be selected individually or used in combination of two or more. Preferably, only one type is selected and used.

[0126] The stirring force in the emulsification process is preferably one that satisfies the conditions defined in definition B below. [Definition B] A stirring force capable of dispersing all of the oil as emulsion droplets when an aqueous solution is prepared by mixing 2 parts by mass of a polyoxyethylene ester ether type nonionic surfactant, 12 parts by mass of a solution containing 1,3-butylene glycol and glycerin in a 1:1 ratio, and 21 parts by mass of water at room temperature, and then stirring this aqueous solution with 65 parts by mass of an oil selected from mineral oil, triethylhexanoin, and olive fruit oil at room temperature to prepare an emulsion composition of 100 parts by mass.

[0127] By stirring with the stirring force defined in definition B, a more stable emulsion composition can be produced without phase separation.

[0128] The specific embodiments of "polyoxyethylene ester ether type nonionic surfactant" in Definition B can be described in the same way as in Definition A. Furthermore, the volume of the mixture of emulsifier, 1,3-butylene glycol and glycerin, water, and oil to be stirred in Definition B can be directly determined using the same method as described in Definition A.

[0129] The oils listed in Definition B may be selected individually or used in combination of two or more. Preferably, only one type is selected and used.

[0130] Furthermore, whether or not "all of the oil is dispersed as emulsified droplets" as defined in definition B can be determined by checking, as described above, whether or not the oil has separated into phases and is floating on top. This determination can be made visually. If no oil that has separated into phases and is floating is observed, it can be determined that "all of the oil is dispersed as emulsified droplets" has been achieved.

[0131] In the emulsification process, it is preferable to use a stirrer that satisfies the conditions defined in definition C below. [Definition C] When 2% by mass of the water-soluble copolymer, 88% by mass of water, and 10% by mass of squalane are stirred at room temperature, the proportion of squalane that cannot be dispersed as an emulsion droplet can be less than 1% by mass.

[0132] The proportion of squalane that cannot be dispersed as an emulsified droplet in definition C is less than 1% by mass, preferably less than 0.5% by mass, and more preferably less than 0.1% by mass.

[0133] By using a stirrer that satisfies the conditions defined in definition C, an emulsified composition without separation can be easily produced. A hand blender is a preferred example of a stirrer that satisfies the conditions defined in definition C.

[0134] In the emulsification process, the phase components that cannot be dispersed as a dispersed phase are emulsified such that the amount is preferably less than 1% by mass, more preferably less than 0.5% by mass, and even more preferably less than 0.1% by mass. In the present invention, since the aforementioned water-soluble copolymer is used, it becomes possible to produce an emulsified composition without such separation. When producing an oil-in-water emulsion composition, the proportion of oil phase components that cannot be dispersed as emulsion droplets should be within the above numerical range. When producing a water-in-oil emulsion composition, the proportion of aqueous phase components that cannot be dispersed as emulsion droplets should be within the above numerical range.

[0135] In the emulsification process, it is preferable to use a stirrer that satisfies the conditions defined in definition D below. [Definition D] When 2% by mass of the aforementioned water-soluble copolymer, 88% by mass of water, and 10% by mass of squalane are stirred at room temperature, the median diameter of the emulsion droplets can be made 30 μm or less.

[0136] In definition D, the median diameter is 30 μm or less, more preferably 20 μm or less, and even more preferably 15 μm or less.

[0137] By using a stirrer that satisfies the conditions defined in definition D, it is possible to produce an emulsified composition with superior stability. A hand blender is a preferred example of a stirrer that satisfies the conditions defined in definition D.

[0138] In the emulsification process, it is preferable to emulsify the emulsion droplets so that the median diameter is 30 μm or less, more preferably 20 μm or less, and even more preferably 15 μm or less. In the present invention, since the aforementioned water-soluble copolymer is used, it becomes possible to produce a stable emulsion composition with small emulsion droplets.

[0139] The median diameter can be measured by observing the image under an optical microscope.

[0140] In the emulsification process, it is preferable to use a stirrer that satisfies the conditions defined in the following definition E. [Definition E] When a mixture of 100g of a carboxyvinyl polymer aqueous solution with a viscosity of 26450 mPa·s or higher, measured under the following conditions, and 1 mL of a 0.5 wt% Red No. 504 aqueous solution is added dropwise, and this mixture is placed in a 200 mL beaker, and the stirrer is fixed in place with a clamp, and the mixture is continuously stirred at 20°C for 5 minutes, the entire mixture cannot be uniformly stained. [conditions] Equipment used: Type B viscometer (manufactured by Shibaura Systems Co., Ltd.) Temperature: 20℃ Rotation speed: 12 rpm Rotor: No. 4 Time: 60sec

[0141] A milk frother is a preferred example of a stirrer that satisfies the conditions defined in definition E.

[0142] The viscosity of the aqueous solution of carboxyvinyl polymer in definition E is preferably 22,000 mPa·s or higher, more preferably 20,000 mPa·s or higher, even more preferably 1,800 mPa·s or higher, even more preferably 16,000 mPa·s or higher, even more preferably 15,500 mPa·s or higher, and particularly preferably 15,150 mPa·s or higher.

[0143] The temperature during the emulsification process is preferably 5°C to 40°C, more preferably 15°C to 35°C. Furthermore, the temperature in the emulsification process is preferably 5°C or higher, more preferably 10°C or higher, even more preferably 15°C or higher, and even more preferably 20°C or higher. The temperature in the emulsification process is preferably 40°C or lower, more preferably 35°C or lower, and even more preferably 30°C or lower. Although emulsification is difficult at room temperature, using the aforementioned water-soluble copolymer as an emulsifier makes emulsification possible at room temperature. Therefore, it is possible to easily manufacture emulsified compositions at home.

[0144] The amount of water-soluble copolymer added in the emulsification process is preferably 0.1 to 50% by mass, more preferably 0.5 to 30% by mass, relative to the total amount of the emulsified composition to be produced. By setting the amount of the water-soluble copolymer added within the aforementioned range, the emulsification stability of the emulsified composition can be further improved.

[0145] The mixing ratio of the aqueous phase component and the oil phase component to be emulsified by stirring during the emulsification process can be appropriately adjusted by changing the ratio of constituent units (a) and (b) in the water-soluble copolymer. The following describes the oil and aqueous phase content when a water-soluble copolymer containing constituent units (a) and (b) in a ratio suitable for forming the oil-in-water emulsion composition described above is used. In this specification, the oil phase and oil phase components, as well as the aqueous phase and aqueous phase components, are described as not containing the water-soluble copolymer of the present invention.

[0146] The amount of oil phase component added in the emulsification process is preferably 0.01 to 80% by mass, more preferably 0.1 to 70% by mass, relative to the total amount of the emulsified composition to be produced. By setting the amount of oil phase component added within the aforementioned range, the emulsification stability of the emulsified composition can be improved. Furthermore, oil phase components refer to oily and lipophilic components, specifically those contained in the oil phase of an emulsified composition.

[0147] In the emulsification process, the mixing mass ratio of the above-mentioned water-soluble copolymer and the oil phase component is preferably 1:100 to 1:0.2, and more preferably 1:70 to 1:0.3. By setting the mass ratio of the water-soluble copolymer to the oil phase component within the aforementioned range, the emulsification stability of the emulsified composition can be improved.

[0148] The mixed mass ratio of the oil phase to the aqueous phase in the emulsification process is preferably 0.1:99.9 to 80:20, and more preferably 1:99 to 65:35. By setting the mass ratio of the oil phase to the aqueous phase within the aforementioned range, a stable oil-in-water emulsion composition can be formed.

[0149] The components contained in the oil phase and aqueous phase are not particularly limited. Examples of oils that make up the oil phase include liquid oils and fats, solid oils and fats, waxes, hydrocarbon oils, higher fatty acids, higher alcohols, synthetic ester oils, silicone oils, and the like.

[0150] Examples of liquid oils include avocado oil, camellia oil, turtle oil, macadamia nut oil, corn oil, mink oil, olive oil, rapeseed oil, egg yolk oil, sesame oil, peach oil, wheat germ oil, sasanqua oil, castor oil, linseed oil, safflower oil, cottonseed oil, elm oil, meadowfoam oil, soybean oil, peanut oil, tea seed oil, kaya oil, rice bran oil, cinnamon oil, Japanese tung oil, jojoba oil, wheat germ oil, triglycerin, glyceryl trioctanoate, and glyceryl triisopalmitate.

[0151] Examples of solid fats include cocoa butter, coconut oil, horse fat, hydrogenated coconut oil, palm oil, beef tallow, sheep fat, hydrogenated beef tallow, palm kernel oil, pork fat, beef bone fat, Japanese wax kernel oil, hydrogenated oil, beef tallow, Japanese wax, and hydrogenated castor oil.

[0152] Examples of waxes include beeswax, candelilla wax, cotton wax, carnauba wax, bayberry wax, privet wax, whale wax, montan wax, rice bran wax, lanolin, kapok wax, lanolin acetate, liquid lanolin, sugarcane wax, isopropyl lanolin fatty acid, hexyl laurate, reduced lanolin, jojoba wax, hard lanolin, shellac wax, POE lanolin alcohol ether, POE lanolin alcohol acetate, POE cholesterol ether, lanolin fatty acid polyethylene glycol, and POE hydrogenated lanolin alcohol ether.

[0153] Examples of hydrocarbon oils include liquid paraffin, ozokerite, pristane, paraffin, ceresin, squalene, petrolatum, and microcrystalline wax.

[0154] Examples of higher fatty acids include lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, 12-hydroxystearic acid, undecylenic acid, and tallic acid.

[0155] Examples of higher alcohols include cetyl alcohol, stearyl alcohol, behenyl alcohol, batyl alcohol, myristyl alcohol, and cetostearyl alcohol.

[0156] Synthetic ester oils include isopropyl myristate, cetyl octanoate, octyldodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyldecyl dimethyloctanoate, cetyl lactate, myristyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, sucrose stearate, sucrose oleate, cholesteryl 12-hydroxystearylate, ethylene glycol di-2-ethylhexylate, dipentaerythritol fatty acid ester, N-alkyl glycol monoisostearate, neopentyl glycol dicaprate, diisostearyl malate, glyceryl di-2-heptylundecanoate, trimethylolpropane tri-2-ethylhexylate, trimethylolpropane triisostearate, and pentane tetra-2-ethylhexylate. Erythritol, glyceryl tri-2-ethylhexylate, trimethylolpropane triisostearate, cetyl 2-ethylhexanoate, 2-ethylhexyl palmitate, glyceryl trimiristicate, glyceride tri-2-heptyl undecanoate, castor oil fatty acid methyl ester, oleic acid oil, cetostearyl alcohol, acetoglyceride, 2-heptyl undecyl palmitate, cetyl palmitate, adipyl Examples include diisobutyl acetate, N-lauroyl-L-glutamic acid-2-octyldodecyl ester, di-2-heptylundecyl adipate, ethyl laurate, di-2-ethylhexyl sebatate, 2-hexyldecyl myristate, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl sebatate, 2-ethylhexyl succinate, ethyl acetate, butyl acetate, amyl acetate, triethyl citrate, and the like.

[0157] Examples of silicone oils include linear polysiloxanes such as dimethylpolysiloxane, methylphenylpolysiloxane, and methylhydrogenpolysiloxane, as well as cyclic polysiloxanes such as decamethylpolysiloxane, dodecamethylpolysiloxane, and tetramethyltetrahydrogenpolysiloxane.

[0158] One or more types of oils may be used.

[0159] The emulsification process may be carried out in a manner that substantially does not involve the addition of emulsifiers other than the water-soluble copolymer described above. Here, "substantially no emulsifiers other than the aforementioned water-soluble copolymers are added" means that the amount of emulsifiers other than the aforementioned water-soluble copolymers added is 0.3% by mass or less, preferably 0.1% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0.001% by mass or less, relative to the total amount of the emulsified composition to be manufactured. Furthermore, it is particularly preferable not to add any emulsifiers other than the aforementioned water-soluble copolymers.

[0160] In the emulsification process, optional additives commonly found in cosmetics may be included. Examples of such additives include humectants such as polyethylene glycol, glycerin, 1,3-butylene glycol, erythritol, sorbitol, xylitol, and maltitol; lower alcohols such as ethanol; antioxidants such as butylhydroxytoluene, tocopherol, and phytic acid; antibacterial agents such as benzoic acid, salicylic acid, sorbic acid, alkyl parahydroxybenzoate, and hexachlorophene; benzoic acid-based UV absorbers such as para-aminobenzoic acid (hereinafter abbreviated as "PABA"), PABA monoglycerin ester, N,N-dipropoxy PABA ethyl ester, N,N-diethoxy PABA ethyl ester, N,N-dimethyl PABA methyl ester, N,N-dimethyl PABA ethyl ester, N,N-dimethyl PABA butyl ester, and N,N-dimethyl PABA 2-ethylhexyl ester; anthranilic acid-based UV absorbers such as homomenthyl-N-acetylanthranilate; and amyl salicylate and menthyl salicylate. Salicylic acid-based UV absorbers such as homomenthyl salicylate, octyl salicylate, phenyl salicylate, benzyl salicylate, and p-isopropanolphenyl salicylate; octyl cinnamate, ethyl-4-isopropyl cinnamate, methyl-2,5-diisopropyl cinnamate, ethyl-2,4-diisopropyl cinnamate, methyl-2,4-diisopropyl cinnamate, propyl-p-methoxy cinnamate, and isopropyl-p-methoxy Cinnamic acid-based UV absorbers such as cinnamate, isoamyl-p-methoxycinnamate, octyl-p-methoxycinnamate (2-ethylhexyl-p-methoxycinnamate), 2-ethoxyethyl-p-methoxycinnamate, cyclohexyl-p-methoxycinnamate, ethyl-α-cyano-β-phenylcinnamate, 2-ethylhexyl-α-cyano-β-phenylcinnamate, and glyceryl mono-2-ethylhexanoyl-diparamethoxycinnamate;[3-Bis(trimethylsiloxy)methylsilyl-1-methylpropyl]-3,4,5-trimethoxycinnamate, [3-Bis(trimethylsiloxy)methylsilyl-3-methylpropyl]-3,4,5-trimethoxycinnamate, [3-Bis(trimethylsiloxy)methylsilylpropyl]-3,4,5-trimethoxycinnamate, [3-Bis(trimethylsiloxy)methylsilylbutyl]-3,4,5-trimethoxycinnamate, [3-Tris(trimethylsiloxy)silylbutyl]-3,4,5-trimethoxycinnamate, Silicone-based cinnamic acid UV absorbers such as [3-tris(trimethylsiloxy)silylbutyl]-3,4,5-trimethoxycinnamate, [3-tris(trimethylsiloxy)silyl-1-methylpropyl]-3,4-dimethoxycinnamate; 2,4-dihydroxybenzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2'-dihydroxy-4,4'-dimethoxybenzophenone, 2,2'-4,4'-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-methoxy Benzophenone-based UV absorbers such as c-4'-methylbenzophenone, 2-hydroxy-4-methoxybenzophenone-5-sulfonate, 4-phenylbenzophenone, 2-ethylhexyl-4'-phenyl-benzophenone-2-carboxylate, 2-hydroxy-4-n-octoxybenzophenone, 4-hydroxy-3-carboxybenzophenone; 3-(4'-methylbenzylidene)-d,l-camphor, 3-benzylidene-d,l-camphor, ethyl urocanate, 2-phenyl-5-methylbenzoxazole, 2 UV absorbers such as 2'-hydroxy-5-methylphenylbenzotriazole, 2-(2'-hydroxy-5'-t-octylphenyl)benzotriazole, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, dibenzarazine, dianisioylmethane, 4-methoxy-4'-t-butyldibenzoylmethane, 5-(3,3'dimethyl-2-norbornylidene)-3-pentan-2-one; organic acids such as acyl sarcosinic acid (e.g., sodium lauroyl sarcosinate), glutathione, citric acid, malic acid, tartaric acid, and lactic acid;Vitamins B, such as vitamin A and its derivatives, vitamin B6 hydrochloride, vitamin B6 tripalmitate, vitamin B6 dioctanoate, vitamin B2 and its derivatives, vitamin B12, vitamin B15 and its derivatives, vitamin E derivatives such as α-tocopherol, β-tocopherol, γ-tocopherol, vitamin E acetate, vitamin D derivatives, vitamin H, vitamins such as pantothenic acid, pantethine, nicotinamide, and benzyl nicotinate; γ-oryzanol, allantoin, glycyrrhizic acid (salt), glycyrrhetinic acid and its derivatives, tranexamic acid Xamic acid and its derivatives [Tranexamic acid derivatives include dimers of tranexamic acid (e.g., trans-4-(trans-aminomethylcyclohexanecarbonyl)aminomethylcyclohexanecarboxylic acid hydrochloride, etc.), esters of tranexamic acid and hydroquinone (e.g., trans-4-aminomethylcyclohexanecarboxylic acid 4'-hydroxyphenyl ester, etc.), esters of tranexamic acid and gentisic acid (e.g., 2-(trans-4-aminomethylcyclohexylcarbonyloxy)-5-hydroxybenzoic acid and its salts, etc.)] [Amides of tranexamic acid (e.g., trans-4-aminomethyl cyclohexanecarboxylic acid methylamide and its salts, trans-4-(p-methoxybinzoyl)aminomethylcyclohexanecarboxylic acid and its salts, trans-4-guanidinomethylcyclohexanecarboxylic acid and its salts, etc.)], hinokitiol, bisabolol, eucarptone, thymol, inositol, saponins such as saikosaponin, ginseng saponin, loofah saponin, and mucrodi saponin, pantothenyl ethyl ether, ethinylestradiol, tranexamic acid, Various drugs such as arbutin, cepharanthine, and placenta extract; extracts of plants such as dock, Sophora flavescens, Nuphar japonica, orange, sage, yarrow, mallow, Swertia japonica, thyme, Angelica acutiloba, spruce, birch, horsetail, loofah, horse chestnut, saxifrage, arnica, lily, mugwort, peony, aloe, gardenia, and cypress; pigments; porous and / or water-absorbing powders (e.g., starches obtained from corn or potatoes, anhydrous silicic acid, talc, kaolin, magnesium aluminum silicate, calcium alginate, etc.); neutralizing agents; preservatives; fragrances;Examples include pigments, etc.

[0161] In the emulsification process, a preferred method involves preparing an aqueous phase component containing the aforementioned water-soluble copolymer and an oil phase component, and then stirring and mixing them together. More specifically, a preferred method involves preparing an aqueous solution in which the above-mentioned water-soluble copolymer is dispersed, mixing this with other aqueous phase components, and then stirring and mixing the mixture of aqueous phase components with a pre-prepared mixture of oil phase components.

[0162] This invention can be applied to the manufacturing methods of cosmetics such as lotions, creams, serums, sunscreens, and liquid foundations, as well as external skin preparations, quasi-drugs, and pharmaceuticals. In particular, given the growing need for preparing homemade cosmetics, the present invention is especially preferable to be applied to the manufacture of cosmetics.

[0163] <3> emulsifying composition The present invention also relates to an emulsified composition produced by the manufacturing method described above. Specific embodiments of the emulsified composition of the present invention can be derived by applying mutatis mutandis the matters described in the section on the manufacturing method of the emulsified composition described above. The emulsified composition of the present invention preferably contains only components with a melting point of less than 40°C and / or components that dissolve or disperse in the aqueous phase at 40°C or below as aqueous phase components. Furthermore, it is preferable that the oil phase components consist only of components with a melting point of less than 40°C, and / or components that dissolve or disperse in the oil phase at 40°C or below. By including only the aforementioned components as the aqueous and oil phase components, an emulsion composition with superior emulsion stability can be prepared. Of the components with a melting point of 40°C or lower, a melting point of 35°C or lower is preferred, and a melting point of 30°C or lower is more preferred. The component that dissolves or disperses in the aqueous or oil phase at 40°C or below is preferably a component that dissolves or disperses in the aqueous or oil phase at 35°C or below, and more preferably a component that dissolves or disperses at 30°C or below.

[0164] The oil phase component is preferably selected from one or more selected from the group consisting of squalane, isostearic acid, oleic acid, linoleic acid, linolenic acid, caprylic / capric triglyceride, polydimethylsiloxane, and cyclopentasiloxane.

[0165] Furthermore, the emulsified composition may be in a form that is substantially free of humectants. Here, "substantially free of humectants" means that the amount of humectant added is 0.3% by mass or less, preferably 0.1% by mass or less, more preferably 0.01% by mass or less, and even more preferably 0.001% by mass or less, relative to the total amount of the emulsified composition to be manufactured. Furthermore, it is particularly preferable not to add any humectant. Polyhydric alcohols, a typical component of humectants, are known to function as co-surfactants in the emulsification process, assisting emulsification by emulsifiers and enhancing emulsion stability.

[0166] Therefore, ensuring emulsion stability in emulsion compositions that do not contain humectants is one of the important challenges. The inventors of the present invention have found that by using the aforementioned water-soluble copolymer as an emulsifier, and examining multiple samples prepared under non-heating conditions, a stable emulsified composition without the addition of a humectant can be prepared by ensuring that the amount of oil in the emulsified composition and the viscosity of the emulsified composition satisfy a certain relationship. Viscosity is known to be an important parameter for restricting the movement of emulsion particles and suppressing coalescence, flotation, and sedimentation.

[0167] It is preferable that the emulsified composition satisfies the following relationship between the amount x (mass%) of oil in the emulsified composition and the viscosity y (mPa·s).

[0168] (Relational expression) y≦-2600x+186000(10≦x≦60)···(1) y≧-110x+4133(10≦x≦30)···(2) y≧140x-3400(30 <x≦60)···(3)

[0169] The viscosity of the emulsified composition can be adjusted by the amount of thickener added. Generally, the higher the amount of thickening agent added, the higher the viscosity of the emulsion composition; conversely, the lower the amount added, the lower the viscosity of the emulsion composition. Furthermore, viscosity can be adjusted by changing the amount of oil added (oil content). Generally, the higher the amount of oil added, the higher the viscosity of the emulsion composition; conversely, the lower the amount of oil added, the lower the viscosity of the emulsion composition.

[0170] Furthermore, it is preferable that the amount x (mass%) of the oily component of the emulsified composition and the viscosity y (mPa·s) satisfy the following relationships (4), (5), or (6) and the above relationships (7), (8), (9), (10), or (11). (Relational expression) y≦-2200x+172000(10≦x≦20)...(4) y≦-3400x+196000(20 <x≦40)···(5) y≦-1700x+128000(40 <x≦60)···(6) y≧-250x+7500(10≦x≦20)···(7) y≧-165x+5800(20 <x≦30)···(8) y≧135x-3200(30 <x≦40)···(9) y≧480x-17000(40 <x≦50)···(10) y≧500x-18000(50 <x≦60)···(11)

[0171] Furthermore, it is preferable that the amount x (mass%) of oil in the emulsified composition and the viscosity y (mPa·s) satisfy the following relationships (12), (13), (14), (15), or (16) and relationships (17), (18), (19), (20), or (21). (Relational expression) y≦-1600x+156000(10≦x≦20)···(12) y≦-5200x+228000(20 <x≦30)···(13) y≦-3200x+168000(30 <x≦40)···(14) y≦-400x+56000(40 <x≦50)···(15) y≦-1300x+101000(50 <x≦60)···(16) y≧-280x+8300(10≦x≦20)···(17) y≧-180x+6300(20 <x≦30)···(18) y≧150x-3600(30 <x≦40)···(19) y≧760x-28000(40 <x≦50)···(20) y≧700x-25000(50 <x≦60)···(21)

[0172] Furthermore, it is preferable that the amount x (mass%) of oil in the emulsified composition and the viscosity y (mPa·s) satisfy the following relationships: (22), (23), (24), (25), or (26) and (27), (28), (29), (30), or (31). (Relational expression) y≦-1640x+152200(10≦x≦20)···(22) y≦-5295x+225300(20 <x≦30)···(23) y≦-3546x+172830(30 <x≦40)···(24) y≦-281x+42230(40 <x≦50)···(25) y≦-718x+64080(50 <x≦60)···(26) y≧-324.3x+9345(10≦x≦20)···(27) y≧-186.6x+6591(20 <x≦30)···(28) y≧-153.3x-3606(30 <x≦40)···(29) y≧-900.4x-33490(40 <x≦50)···(30) y≧847x-30820(50 <x≦60)···(31)

[0173] In addition, the inventors of the present invention have found that an emulsified composition in which the carboxyvinyl polymer concentration x (mass%) and the blending amount y (mass%) of the oil agent satisfy the following relational expressions (32), (33), or (34) and also satisfy the following relational expressions (35), (36), or (37) has excellent emulsification stability. (Relational Expression) y ≦ -0.0725x + 2.525 (10 ≦ x ≦ 30) ··· Relational Expression (32) y ≦ -0.02x + 0.95 (30 < x ≦ 40) ··· Relational Expression (33) y ≦ -0.0056x + 0.374 (40 < x ≦ 60) ··· Relational Expression (34) y ≧ -0.0024x + 0.104 (10 ≦ x ≦ 30) ··· Relational Expression (35) y ≧ -0.032 (30 < x ≦ 50) ··· Relational Expression (36) y ≧ -0.001x + 0.082 (50 < x ≦ 60) ··· Relational Expression (37)

[0174] Preferably, in the emulsified composition, the blending amount x (mass%) of the oil agent and the carboxyvinyl polymer concentration y (mass%) satisfy the following relational expressions (38), (39), or (40) and also satisfy the following relational expressions (41), (42), (43). (Relational Expression) y ≦ -0.065x + 2.25 (10 ≦ x ≦ 30) ··· Relational Expression (38) y ≦ -0.018x + 0.84 (30 < x ≦ 40) ··· Relational Expression (39) y ≦ -0.0042x + 0.288 (40 < x ≦ 60) ··· Relational Expression (40) y ≧ -0.0027x + 0.117 (10 ≦ x ≦ 30) ··· Relational Expression (41) y ≧ 0.036 (30 < x ≦ 50) ··· Relational Expression (42) y ≧ -0.001x + 0.085 (50 < x ≦ 60) ··· Relational Expression (43)

[0175] More preferably, in the emulsion composition, the blending amount x (mass %) of the oil agent and the concentration y (mass %) of the carboxyvinyl polymer satisfy the following relational expressions (44), (45), (46), (47), or (48) and also satisfy the following relational expressions (49), (50), (51), or (52). (Relational expression) y ≦ -0.046x + 1.84 (10 ≦ x ≦ 20) ··· Relational expression (44) y ≦ -0.067x + 2.26 (20 < x ≦ 30) ··· Relational expression (45) y ≦ -0.015x + 0.7 (30 < x ≦ 40) ··· Relational expression (46) y ≦ -0.003x + 0.22 (40 < x ≦ 50) ··· Relational expression (47) y ≦ -0.0035x + 0.245 (50 ≦ x ≦ 60) ··· Relational expression (48) y ≧ -0.003x + 0.137 (10 ≦ x ≦ 20) ··· Relational expression (49) y ≧ -0.0023x + 0.109 (20 < x ≦ 30) ··· Relational expression (50) y ≧ 0.04 (30 < x ≦ 50) ··· Relational expression (51) y ≧ -0.001x + 0.09 (50 < x ≦ 60) ··· Relational expression (52)

[0176] An emulsion composition satisfying the above relationships is excellent in emulsion stability.

[0177] Further, the production method of the present invention preferably includes a step of determining the blending amount of the oil agent and the amount of the thickener so as to satisfy the above relational expressions. Further, the production method of the present invention preferably includes a step of determining the blending amount of the oil agent and the concentration of the carboxyvinyl polymer so as to satisfy the above relational expressions.

[0178] <4> Production kit for emulsion composition The present invention also relates to a production kit for an emulsion composition. The production kit for the emulsified composition of the present invention includes, as its components, a first packaging container filled with the above-mentioned water-soluble copolymer. The water-soluble copolymer filled in the first packaging container may be in a non-liquid form such as solid or powder, but it is preferably filled in a liquid form. Specifically, the water-soluble copolymer is preferably filled in the first packaging container in a state of being dispersed in water.

[0179] When filling the first packaging container with the aqueous dispersion of the water-soluble copolymer described above, the content of the water-soluble copolymer in the aqueous dispersion is not particularly limited, but as a guideline, it can be preferably 0.01 to 99% by mass, more preferably 1 to 90% by mass.

[0180] The volume of the aqueous dispersion of the water-soluble copolymer filled in the first packaging container is not particularly limited, but as a guideline, it is preferably 1 to 1000 ml, more preferably 10 to 500 ml.

[0181] The production kit for the emulsified composition of the present invention includes, as its components, a second packaging container filled with an oil phase component. The oil phase component filled in the second packaging container may be solid or liquid at room temperature, but it is preferably liquid at room temperature. When the oil phase component filled in the second packaging container is solid at room temperature, warm the second packaging container with hot water or the like to make the oil phase component liquid before use.

[0182] The volume of the oil phase component filled in the second packaging container is not particularly limited, but as a guideline, it is preferably 1 to 1000 ml, more preferably 10 to 500 ml.

[0183] Examples of the oil phase component filled in the second packaging container include the oils described in the item "<2> Method for producing an emulsified composition" above, such as liquid oils and fats, solid oils and fats, waxes, hydrocarbon oils, higher fatty acids, higher alcohols, synthetic ester oils, silicone oils, and the like.

[0184] The oil phase component to be filled in the second packaging container is preferably based on the oil agent described in the item of "<2> Method for producing an emulsion composition". Although not particularly limited, specifically, as a guide, preferably 50% by mass or more, more preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass or more, still more preferably 90% by mass or more, and still more preferably 95% by mass or more of the oil phase component is composed of the above oil agent. The total amount of the oil phase component to be filled in the second packaging container may be composed of the oil agent described in the item of "<2> Method for producing an emulsion composition".

[0185] As the oil phase component to be filled in the second packaging container, it may be in a form that contains in advance an oil-soluble optional component other than the above-described base oil. Specifically, among the optional additive components listed in the item of "<2> Method for producing an emulsion composition", those having oil solubility may be appropriately blended.

[0186] The production kit for the emulsion composition of the present invention includes, as its component, a third packaging container filled with an aqueous phase component. The aqueous phase component filled in the third packaging container may be entirely water, preferably purified water. It may also be an aqueous solution or a water dispersion in which an optional component is dissolved or dispersed.

[0187] The volume of the aqueous phase component to be filled in the third packaging container is not particularly limited, but as a guide, it is preferably 1 to 1000 ml, more preferably 10 to 500 ml.

[0188] When filling an aqueous solution or a water dispersion in the third packaging container, the content of the solute or the dispersoid is not particularly limited, but as a guide, it is preferably 0.01 to 90% by mass, more preferably 0.1 to 80% by mass.

[0189] When filling an aqueous solution or a water dispersion containing an optional component in advance in the third packaging container, as the solute or the dispersoid, among the optional additive components listed in the item of "<2> Method for producing an emulsion composition", those having water solubility or hydrophilicity can be appropriately blended.

[0190] Furthermore, the third packaging container may be filled with an aqueous dispersion containing the aforementioned water-soluble copolymer. In other words, the embodiment may be designed to prepare an emulsion composition by mixing the oil phase component filled in the second packaging container with the aqueous phase component containing the water-soluble copolymer filled in the third packaging container. In this case, the packaging may not include a first packaging container filled with a water-soluble copolymer or an aqueous dispersion thereof, but may instead consist only of a second packaging container and a third packaging container.

[0191] The preparation kit of the present invention makes it possible for consumers to prepare homemade emulsified compositions at home. Specifically, an emulsified composition can be prepared by pouring the water-soluble copolymer, oil phase component, and aqueous phase component, which are filled in each of the first to third packaging containers, into any container to prepare a mixture, and then stirring it. The proportions of the water-soluble copolymer, oil-phase component, and aqueous-phase component can be adjusted to suit consumer preferences. Furthermore, any active ingredient can be added as appropriate to suit consumer preferences. In other words, the kit of this invention allows for the preparation of original emulsified compositions. Furthermore, the preparation kit of the present invention allows for the preparation of an emulsion composition without heating by using the water-soluble copolymer as an emulsifier. In other words, it is possible to produce an emulsion composition of stable quality without variations in the quality of the emulsion composition (emulsification stability, emulsion particle size, etc.) due to the degree of heating. Furthermore, because the manufacturing kit of the present invention offers a high degree of freedom in composition, consumers can change the ingredients and their proportions to achieve their preferred texture and feel.

[0192] When preparing an emulsified composition using the kit of the present invention, it is not necessary to use a powerful industrial-grade stirring device. Even when using a household stirring device with limited stirring power, an emulsified composition without separation of the oil phase and the aqueous phase can be easily prepared.

[0193] The present invention may also include an agitator as a component of the manufacturing kit. When an agitator is included as a component of the manufacturing kit, specific details regarding the type of agitator, agitation force, etc., are described above. <2> The methods described in "Method for Manufacturing Emulsified Compositions" can be applied as is.

[0194] Furthermore, the preparation kit of the present invention may include a container for preparing the emulsified composition. Preferably, this container may be one with markings, and more preferably, a beaker with markings. Including a container with markings makes it easier for consumers to adjust and confirm the mixing ratio of the water-soluble copolymer, oil phase component, and aqueous phase component.

[0195] Furthermore, the kit may include instructions outlining the approximate mixing ratios of the water-soluble copolymer, oil-phase component, and aqueous-phase component.

[0196] The preparation kit may include a fourth packaging container filled with plant extracts that have a beneficial effect on the skin, or aromatic oils for fragrance. The ingredients in the fourth packaging container can be incorporated into the emulsified composition according to consumer preferences.

[0197] The manufacturing kit of the present invention can be configured such that all components included in the kit are packaged in a single packaging container. Such a configuration facilitates transportation and sales.

[0198] <5> Method for designing emulsified compositions The present invention also relates to a method for designing emulsified compositions that are emulsified without heating. The present invention includes a step of selecting a component having a melting point of 40°C or lower, and / or a component that dissolves or disperses in the aqueous phase at 40°C or lower, as the aqueous phase component. The process also includes a step of selecting components for the oil phase that have a melting point of 40°C or lower, and / or components that dissolve or disperse in the aqueous phase at 40°C or lower.

[0199] As the aqueous phase component and the oil phase component, the matters described in "<2> Method for Producing Emulsion Composition" and the matters described in "<3> Emulsion Composition" can be applied.

Example

[0200] <Test Example 1> As a water-soluble copolymer, a copolymer of glyceryl diisostearate methacrylate, which is a hydrophobic monomer, and methoxy PEG-23 methacrylate, which is a hydrophilic monomer, with an average molecular weight of 61,000 and a mass ratio of approximately 3:7 ((glyceryl diisostearate methacrylate / methoxy PEG-23 methacrylate) copolymer) was used to prepare an emulsion composition.

[0201] Specifically, first, 1 part by mass of the above-mentioned water-soluble copolymer, 12 parts by mass of a humectant obtained by mixing 1,3-butylene glycol and glycerin at a ratio of 1:1, and 22 parts by mass of water were mixed at room temperature to prepare an aqueous solution. To this aqueous solution, 65 parts by mass of 11 types of oils with different structures listed in Table 1 were added to make a total of 150 ml of a mixed solution, which was stirred at high speed for 30 seconds using a household cooking mixer (HB-1230, HadinEEon) to prepare 100 parts by mass of an emulsion composition.

[0202] For comparison, instead of the above-mentioned water-soluble copolymer, 2 parts by mass of a polyoxyethylene ester ether type nonionic surfactant (POE surfactant) or 0.3 parts by mass of an acrylic acid-methacrylic acid copolymer (AAMA polymer) was used, and an emulsion composition was prepared under the same conditions. By adjusting the amount of water added, the total was adjusted to 100 parts by mass.

[0203] The POE surfactant and AAMA polymer used are specifically as follows. POE surfactant: Polyoxyethylene hydrogenated castor oil AAMA polymer: (Acrylates / Alkyl Acrylate (C10-30)) Cross Polymer

[0204] Immediately after preparation, the separation of the oil and aqueous phases of the emulsified composition was visually evaluated to determine whether emulsification was successful, that is, whether all of the oil was dispersed as emulsified droplets. The evaluation results are shown in Table 1. As a representative example, photographs of compositions after stirring using squalane as the oil and POE surfactant, AAMA polymer, and water-soluble copolymer as emulsifiers are shown in Figures 1 and 2.

[0205] [Table 1]

[0206] As a result, POE surfactants were unable to completely emulsify 8 out of 11 oil types (Table 1). Furthermore, AAMA polymers showed separation of the aqueous and oil phases when all oils were used (Table 1). On the other hand, when a water-soluble copolymer was used, it was confirmed that complete emulsification was achieved without separation of the oil phase in all cases using the 11 types of oils (Table 1).

[0207] The above results demonstrate that when the aforementioned water-soluble copolymer is used as an emulsifier, an emulsified composition without separation of the oil phase and the aqueous phase can be produced even when using a household stirrer with limited stirring power. In other words, by using the aforementioned water-soluble copolymer as an emulsifier, consumers can prepare homemade emulsified compositions, more specifically emulsified cosmetics, at home using a household stirrer, without having to use industrially used, high-powered stirring equipment.

[0208] Furthermore, these results demonstrate that by using the aforementioned water-soluble copolymer as an emulsifier, an emulsified composition can be produced without separation of the oil phase and aqueous phase, even without heating during emulsification. In other words, by using the aforementioned water-soluble copolymer as an emulsifier, an emulsified composition can be prepared with low energy consumption.

[0209] <Test Example 2> One part by mass of the water-soluble copolymer used in Test Example 1 was mixed with 88 parts by mass of water, and 10 parts by mass of squalane was added to this mixture. The mixture was then stirred at room temperature using the following various stirring methods. • Hand blender (HB-1230, HadinEEon) • Milk frother (Rechargeable milk frother, Kitdine) • Research-grade stirrer (handheld homogenizer (NS360D, Microtec)). ·Hand stirring

[0210] Emulsified compositions prepared using various stirring methods were observed under a microscope to confirm the size of the emulsion droplets (microscopic images are shown in Figure 3). The median diameter was also measured using an optical microscope. The median diameter of the emulsion droplets of the emulsion compositions prepared by various stirring methods is shown below. • Hand blender • 3.9μm • Milk frother: 5.6μm • Research-grade stirrer • 3.6 μm Manual stirring... Measurement impossible

[0211] The above results demonstrate that, regardless of the stirring method used, emulsified compositions can be prepared at home using the aforementioned water-soluble copolymers without the need for powerful research or industrial stirrers. Furthermore, the study demonstrates that using a hand blender allows for the preparation of smaller, more stable emulsified compositions.

[0212] Furthermore, these results demonstrate that, regardless of the stirring method used, the emulsified composition can be prepared without heating by using the aforementioned water-soluble copolymer, meaning that the emulsified composition can be prepared with lower energy consumption.

[0213] <Test Example 3> Using the water-soluble copolymer used in Test Example 1, emulsified compositions of Examples 1 and 2 were prepared under non-heating conditions according to the compositions listed in Table 2 below, and emulsified compositions of Examples 3 and 4 were prepared under heating conditions. The numbers in the table represent mass percent. Furthermore, using the aforementioned AAMA polymer as an emulsifier, the emulsified compositions of Comparative Examples 1 and 2 were prepared under non-heating conditions, and the emulsified compositions of Comparative Examples 3 and 4 were prepared under heating conditions. For reference examples 1-3, emulsified compositions were prepared under heating according to the compositions listed in Table 2. Furthermore, for each prepared emulsified composition (Examples 1-4 and Comparative Examples 1-4), the surface condition was observed visually immediately after preparation, after storage at -10°C for 1 week, after storage at 20°C for 1 month, and after storage at 5°C for 1 month. The surface condition was evaluated according to the following evaluation criteria. In addition, emulsified particles were confirmed using an optical microscope. The results are shown in Table 2, Figure 4, and Figure 5.

[0214] (Evaluation Criteria) ○: Fully emulsified △: A small amount of oil is floating on top. ×: The emulsion is uneven and oil is floating on top. ××: A large amount of oil is floating on top.

[0215] [Table 2]

[0216] The results shown in Figures 4 and 5 indicate that the emulsified compositions of Examples 1 to 4 did not show oil separation immediately after preparation and were emulsified compositions without separation of the oil phase and aqueous phase. On the other hand, oil separation was observed immediately after preparation in the emulsified compositions of Comparative Examples 1 to 4. These results demonstrate that by using the aforementioned water-soluble copolymer as an emulsifier, it is possible to prepare a more stable emulsified composition compared to conventional polymer emulsifiers.

[0217] Reference Example 1, which used AAMA polymer and sorbitan stearate in combination, showed slight oil separation immediately after preparation. Reference Example 2, which used AAMA polymer, PEG stearate, and sorbitan stearate in combination, showed no oil separation and was completely emulsified. These results indicate that while conventional emulsified compositions using polymer emulsifiers could be prepared under heating and in combination with other emulsifiers to produce good emulsified compositions, the present invention demonstrates that good emulsified compositions can be prepared by using the aforementioned water-soluble copolymer alone as an emulsifier.

[0218] Furthermore, as shown in Figures 4 and 5, when the emulsified compositions of Examples 1 to 4 were stored under various temperature conditions after preparation, some showed slight oil separation, but this did not significantly impair the stability of the emulsion. On the other hand, when the emulsified compositions of Comparative Examples 1 to 4 were stored under the same conditions, a significant amount of oil separation was observed. These results demonstrate that by using the aforementioned water-soluble copolymer as an emulsifier, there are no problems with emulsification stability even when the emulsified composition is prepared under non-heating conditions, and that an emulsified composition with superior emulsification stability compared to conventional polymer emulsifiers can be prepared.

[0219] <Test Example 4> Using the water-soluble copolymer used in Test Example 1 as an emulsifier, an emulsified composition with the composition shown in Table 3 was prepared using a household stirrer under non-heating conditions. Emulsified particles were observed in each prepared sample immediately after preparation and after storage for one month (25°C) using an optical microscope. The results are shown in Figure 5. Furthermore, to evaluate the structural stability of the emulsified compositions, static viscosity measurements were performed using a rheometer immediately after preparation of each sample and after storage for one month (at 25°C). The results are shown in Figure 6.

[0220] [Table 3]

[0221] As shown in Figure 5, no significant changes were observed in the oil droplets immediately after preparation and after storage for one month (at 25°C). These results indicate that the emulsified composition prepared by the manufacturing method of the present invention has excellent long-term stability.

[0222] Furthermore, the results in Figure 6 confirm that all samples, both immediately after preparation and after storage for one month (25°C), exhibited share thinning (a behavior in which viscosity decreases when shear force is applied), which is characteristic of emulsion structures.

[0223] Furthermore, as shown in Figure 7, when comparing the viscosity immediately after preparation and after storage for one month at a shear rate of 1 / s, no significant change in viscosity was observed. These results demonstrate that the emulsified composition produced by the manufacturing method of the present invention retains its emulsion structure even after one month of storage, showing excellent long-term stability.

[0224] These results demonstrate that, according to the manufacturing method of the present invention, emulsified compositions of various compositions can be prepared by using a specific water-soluble copolymer as an emulsifier. In cosmetics such as emulsified compositions, the feel and usability during use are major selling points, and these are greatly influenced by the ingredients used and their proportions. The manufacturing method and emulsified composition preparation kit of the present invention offer a high degree of freedom in composition, allowing consumers to change the ingredients and proportions to achieve their preferred feel and usability.

[0225] <Test Example 5> Next, we investigated the preparation of emulsified compositions that do not contain humectants. Specifically, samples were prepared with oil content of 10%, 20%, 30%, 40%, 50%, and 60% by mass, using the water-soluble copolymer from Test Example 1 as the emulsifier and carboxyvinyl polymer ("Syntalen K" (manufactured by 3V Sigma)) as the thickener, and stored for 4 months (25°C). For each sample, the amount of oil (x, by mass%) was plotted on the x-axis and the carboxyvinyl polymer (carbomer) concentration (by mass%) on the y-axis to create a phase diagram (Figure 8). Furthermore, for the same sample, a phase diagram was created by plotting the amount of oil (mass%) on the x-axis and the viscosity of the emulsion composition (mPa·s) on the y-axis (Figure 10). Table 4 shows the composition of each sample that remained stable after 4 months of storage. Table 5 shows the oil content and viscosity of the samples that developed creaming after 4 months. Table 6 shows the oil content and carbomer concentration of the samples that developed creaming after 4 months.

[0226] [Table 4] [Table 5] [Table 6]

[0227] The results shown in Figure 8 indicate that, according to the manufacturing method of the present invention, by satisfying a specific relationship between the amount of oil (mass%) and the viscosity y (mPa·s) of the emulsion composition, a particularly stable emulsion composition without added humectants can be produced.

[0228] Furthermore, as the oil content increased to 40%, 50%, and 60% by mass, the viscosity range for a highly stable emulsion composition tended to narrow. One reason for this is that as the amount of oil increased, the amount of thickener that could be added to the aqueous phase became limited, making it difficult to obtain a wide range of samples with different viscosities. Therefore, compared to the carbomer used in this test example, it is thought that by using a thickener that produces a higher viscosity at the same volume, or a thickener that produces a lower viscosity at the same volume, the viscosity range for a stable emulsion composition can be broadened to some extent, even at high oil concentrations. Thus, considering the common technical knowledge at the time of this application, an emulsified composition with oil volume x (mass%) and viscosity y (mPa·s) that satisfies the following relationship (1) and relationship (2) or (3) will be a highly stable emulsified composition.

[0229] (Relational expression) y≦-2600x+186000(10≦x≦60)···(1) y≧-110x+4133(10≦x≦30)···(2) y≧140x-3400(30 <x≦60)···(3)

[0230] Furthermore, it is preferable that the amount of oil added x (mass%) and the viscosity y (mPa·s) of the emulsified composition satisfy the following relationships (4), (5), or (6) and the above relationships (7), (8), (9), (10), or (11). (Relational expression) y≦-2200x+172000(10≦x≦20)...(4) y≦-3400x+196000(20 <x≦40)···(5) y≦-1700x+128000(40 <x≦60)···(6) y≧-250x+7500(10≦x≦20)···(7) y≧-165x+5800(20 <x≦30)···(8) y≧135x-3200(30 <x≦40)···(9) y≧480x-17000(40 <x≦50)···(10) y≧500x-18000(50 <x≦60)···(11)

[0231] Furthermore, it is preferable that the amount of oil added x (mass%) and the viscosity y (mPa·s) of the emulsion composition satisfy the following relationships (12), (13), (14), (15), or (16) and relationships (17), (18), (19), (20), or (21). (Relational expression) y≦-1600x+156000(10≦x≦20)···(12) y≦-5200x+228000(20 <x≦30)···(13) y≦-3200x+168000(30 <x≦40)···(14) y≦-400x+56000(40 <x≦50)···(15) y≦-1300x+101000(50 <x≦60)···(16) y≧-280x+8300(10≦x≦20)···(17) y≧-180x+6300(20 <x≦30)···(18) y≧150x-3600(30 <x≦40)···(19) y≧760x-28000(40 <x≦50)···(20) y≧700x-25000(50 <x≦60)···(21)

[0232] Furthermore, it is preferable that the amount of oil added x (mass%) and the viscosity y (mPa·s) of the emulsion composition satisfy the following relationships (22), (23), (24), (25), or (26) and (27), (28), (29), (30), or (31). (Relational expression) y≦-1640x+152200(10≦x≦20)···(22) y≦-5295x+225300(20 <x≦30)···(23) y≦-3546x+172830(30 <x≦40)···(24) y≦-281x+42230(40 <x≦50)···(25) y≦-718x+64080(50 <x≦60)···(26) y≧-324.3x+9345(10≦x≦20)···(27) y ≧ -186.6x + 6591 (20 < x ≦ 30) ··· (28) y ≧ -153.3x - 3606 (3 < x ≦ 40) ··· (29) y ≧ -900.4x - 33490 (40 < x ≦ 50) ··· (30) y ≧ 847x - 30820 (50 < x ≦ 60) ··· (31)

[0233] Figure 9 shows the plot of each relational expression in Figure 8.

[0234] Next, from the results of Figure 10, according to the manufacturing method of the present invention, it was found that by satisfying the specific relationship between the blending amount x (mass%) of the oil agent and the carboxyvinyl polymer concentration y (mass%), it is possible to produce an emulsified composition without a humectant with particularly high stability. Specifically, as long as the oil amount x (mass%) and the carboxyvinyl polymer concentration y (mass%) satisfy the following relational expressions (32), (33), or (34) and also satisfy the relationship of the relational expressions (35), (36), or (37), it will be an emulsified composition with high stability.

[0235] (Relational expression) y ≦ -0.0725x + 2.525 (10 ≦ x ≦ 30) ··· Relational expression (32) y ≦ -0.02x + 0.95 (30 < x ≦ 40) ··· Relational expression (33) y ≦ -0.0056x + 0.374 (40 < x ≦ 60) ··· Relational expression (34) y ≧ -0.0024x + 0.104 (10 ≦ x ≦ 30) ··· Relational expression (35) y ≧ -0.032 (30 < x ≦ 50) ··· Relational expression (36) y ≧ -0.001x + 0.082 (50 < x ≦ 60) ··· Relational expression (37)

[0236] Preferably, in the emulsified composition, the blending amount x (mass%) of the oil agent and the carboxyvinyl polymer concentration y (mass%) satisfy the following relational expressions (38), (39), or (40) and also satisfy the following relational expressions (41), (42), (43). (Relational expression) y ≤ -0.065x + 2.25 (10 ≤ x ≤ 30) ··· Relational Expression (38) y ≤ -0.018x + 0.84 (30 < x ≤ 40) ··· Relational Expression (39) y ≤ -0.0042x + 0.288 (40 < x ≤ 60) ··· Relational Expression (40) y ≥ -0.0027x + 0.117 (10 ≤ x ≤ 30) ··· Relational Expression (41) y ≥ 0.036 (30 < x ≤ 50) ··· Relational Expression (42) y ≥ -0.001x + 0.085 (50 < x ≤ 60) ··· Relational Expression (43)

[0237] More preferably, in the emulsion composition, the blending amount x (mass%) of the oil agent and the carboxyvinyl polymer concentration y (mass%) satisfy the following relational expressions (44), (45), (46), (47), or (48), and satisfy the following relational expressions (49), (50), (51), or (52). (Relational Expression) y ≤ -0.046x + 1.84 (10 ≤ x ≤ 20) ··· Relational Expression (44) y ≤ -0.067x + 2.26 (20 < x ≤ 30) ··· Relational Expression (45) y ≤ -0.015x + 0.7 (30 < x ≤ 40) ··· Relational Expression (46) y ≤ -0.003x + 0.22 (40 < x ≤ 50) ··· Relational Expression (47) y ≤ -0.0035x + 0.245 (50 ≤ x ≤ 60) ··· Relational Expression (48) y ≥ -0.003x + 0.137 (10 ≤ x ≤ 20) ··· Relational Expression (49) y ≥ -0.0023x + 0.109 (20 < x ≤ 30) ··· Relational Expression (50) y ≥ 0.04 (30 < x ≤ 50) ··· Relational Expression (51) y ≥ -0.001x + 0.09 (50 < x ≤ 60) ··· Relational Expression (52)

[0238] Figure 11 shows the plotting of each relational expression in Figure 10.

Industrial Applicability

[0239] This invention can be applied to a kit for making emulsified cosmetics for home use.

Claims

1. A water-soluble copolymer having one or more constituent units (a) derived from a hydrophobic monomer represented by the following general formula (II) and one or more constituent units (b) derived from a hydrophilic monomer as essential constituent units, Oil phase components, Aqueous phase components and, This includes the step of emulsifying using a household stirrer, The hydrophilic monomer is a hydrophilic monomer represented by the following general formula (IV), The mass ratio of the constituent unit (a) to the constituent unit (b) is 10:90 to 50:

50. A step of measuring the viscosity of the emulsified composition, The process includes a step of determining the amount of oil and the amount of thickener such that the amount of oil x (mass%) and the viscosity y (mPa·s) of the emulsion composition satisfy the following relation (1) and also satisfy relation (2) or (3). A method for producing an emulsified composition. General formula (II) (II) (In general formula (II), R3 represents an alkyl group having 1 to 3 carbon atoms, R4 and R5 may be the same or different, and represent a branched acyl group having 6 to 22 carbon atoms that does not contain a ring structure. X represents a group obtained by removing an OH group from a trivalent alcohol.) General formula (IV) (IV) (IV) (In general formula (IV), R10 represents an alkyl group having 1 to 3 carbon atoms, R11 represents an alkylene group having 2 to 4 carbon atoms which may have a hydroxyl group, and R12 represents an aromatic hydrocarbon group having 6 to 10 carbon atoms, an aliphatic hydrocarbon group having 1 to 14 carbon atoms, or an acyl group having 1 to 12 carbon atoms. n represents an integer from 6 to 40.) (Relational expression) y≦-2600x+186000 (10≦x≦60) (1) y≧-120x+4133 (10≦x≦30) (2) y ≥ 140x - 3400 (30 < x ≤ 60) (3)

2. The manufacturing method according to claim 1, wherein the household stirring device is selected from a hand blender, a handheld milk frother, a tabletop mixer, a tabletop food processor, and an electric whisk.

3. The manufacturing method according to claim 1 or 2, wherein the weight of the household agitator is 10 kg or less.

4. A water-soluble copolymer having one or more constituent units (a) derived from a hydrophobic monomer represented by the following general formula (II) and one or more constituent units (b) derived from a hydrophilic monomer as essential constituent units, Oil phase components, Aqueous phase components and The process includes a step of emulsifying by stirring with a stirring force that satisfies the conditions defined in Definition A below, The hydrophilic monomer is a hydrophilic monomer represented by the following general formula (IV), The mass ratio of the constituent unit (a) to the constituent unit (b) is 10:90 to 50:

50. A step of measuring the viscosity of the emulsified composition, The process includes a step of determining the amount of oil and the amount of thickener such that the amount of oil x (mass%) and the viscosity y (mPa·s) of the emulsion composition satisfy the following relation (1) and also satisfy relation (2) or (3). A method for producing an emulsified composition. General formula (II) (II) (In general formula (II), R3 represents an alkyl group having 1 to 3 carbon atoms, R4 and R5 may be the same or different, and represent a branched acyl group having 6 to 22 carbon atoms that does not contain a ring structure. X represents a group obtained by removing an OH group from a trivalent alcohol.) General formula (IV) (IV) (IV) (In general formula (IV), R10 represents an alkyl group having 1 to 3 carbon atoms, R11 represents an alkylene group having 2 to 4 carbon atoms which may have a hydroxyl group, and R12 represents an aromatic hydrocarbon group having 6 to 10 carbon atoms, an aliphatic hydrocarbon group having 1 to 14 carbon atoms, or an acyl group having 1 to 12 carbon atoms. n represents an integer from 6 to 40.) [Definition A] A stirring force is required to prepare an aqueous solution by mixing 2 parts by mass of a polyoxyethylene ester ether type nonionic surfactant or 0.3 parts by mass of an acrylic acid / methacrylic acid copolymer as an emulsifier, 12 parts by mass of a solution containing 1,3-butylene glycol and glycerin in a 1:1 ratio, and the remainder of water at room temperature. Then, 100 parts by mass of the emulsion composition is prepared by stirring this aqueous solution with 65 parts by mass of an oil selected from group A below at room temperature, and the stirring force is required to disperse all of the oil as emulsion droplets. (A) Squalane, mineral oil, isostearic acid, oleic acid, linoleic acid, linolenic acid, caprylic / capric triglyceride, triethylhexanoin, olive fruit oil, polydimethylsiloxane, cyclopentasiloxane (However, when selecting a polyoxyethylene ester ether type nonionic surfactant as an emulsifier, mineral oil, triethylhexanoin, and olive fruit oil from Group A are not selected.) (Relational expression) y≦-2600x+186000 (10≦x≦60) (1) y≧-120x+4133 (10≦x≦30) (2) y ≥ 140x - 3400 (30 < x ≤ 60) (3)

5. The manufacturing method according to claim 4, characterized in that the stirring force further satisfies the conditions defined by definition B below. [Definition B] A stirring force is required to prepare an aqueous solution by mixing 2 parts by mass of a polyoxyethylene ester ether type nonionic surfactant, 12 parts by mass of a solution containing 1,3-butylene glycol and glycerin in a 1:1 ratio, and 21 parts by mass of water at room temperature. This aqueous solution is then stirred at room temperature with 65 parts by mass of an oil selected from mineral oil, triethylhexanoin, and olive fruit oil to prepare an emulsified composition of 100 parts by mass, and the stirring force is required to disperse all of the oil as emulsified droplets.

6. The manufacturing method according to any one of claims 1 to 5, wherein the emulsification step is performed using a stirrer that satisfies the conditions defined by the following definition C. [Definition C] When 2% by mass of the water-soluble copolymer, 88% by mass of water, and 10% by mass of squalane are stirred at room temperature, the proportion of squalane that cannot be dispersed as an emulsion droplet can be less than 1% by mass.

7. The manufacturing method according to any one of claims 1 to 6, wherein in the emulsifying step, the amount of phase components that cannot be dispersed as a dispersed phase is less than 1% by mass.

8. The manufacturing method according to any one of claims 1 to 7, wherein the emulsification step is performed using a stirrer that satisfies the conditions defined by the following definition D. [Definition D] When 2% by mass of the aforementioned water-soluble copolymer, 88% by mass of water, and 10% by mass of squalane are stirred at room temperature, the median diameter of the emulsion droplets can be made 30 μm or less.

9. The manufacturing method according to any one of claims 1 to 8, wherein in the emulsification step, the emulsification is carried out so that the median diameter of the emulsified droplet is 30 μm or less.

10. The manufacturing method according to any one of claims 1 to 9, wherein the emulsification step is performed using a stirrer that satisfies the conditions defined by the following definition E. [Definition E] When a mixture of 100 g of a carboxyvinyl polymer aqueous solution with a viscosity of 26,450 mPa·s or higher, measured under the following conditions, and 1 mL of a 0.5 wt% Red No. 504 aqueous solution is added dropwise, and this mixture is placed in a 200 mL beaker, and the stirrer is fixed in place with a clamp, and the mixture is continuously stirred at 20°C for 5 minutes, the entire mixture cannot be uniformly stained. [conditions] Equipment used: Type B viscometer (manufactured by Shibaura Systems Co., Ltd.) Temperature: 20℃ Rotation speed: 12 rpm Rotor: No. 4 Time: 60sec

11. A manufacturing method according to any one of claims 1 to 10, comprising the step of determining the amount of oil and the amount of thickener such that the amount of oil x (mass%) and the viscosity y (mPa·s) of the emulsion composition satisfy the following relational formulas (4), (5), or (6) and the following relational formulas (7), (8), (9), (10), or (11). (Relational expression) y≦-2200x+172000 (10≦x≦20)...(4) y≦-3400x+196000 (20<x≦40)...(5) y≦-1700x+128000 (40<x≦60)...(6) y≧-250x+7500 (10≦x≦20)...(7) y≧-165x+5800 (20<x≦30)...(8) y ≥ 135x - 3200 (30 < x ≤ 40) ... (9) y ≥ 480x - 17000 (40 < x ≤ 50) ... (10) y ≥ 500x - 18000 (50 < x ≤ 60) ... (11)

12. A manufacturing method according to any one of claims 1 to 10, comprising the step of determining the amount of oil and the amount of thickener such that the amount of oil x (mass%) and the viscosity y (mPa·s) of the emulsion composition satisfy the following relational formulas (12), (13), (14), (15), or (16) and relational formulas (17), (18), (19), (20), or (21). (Relational expression) y≦-1600x+156000 (10≦x≦20)...(12) y≦-5200x+228000 (20<x≦30)...(13) y≦-3200x+168000 (30<x≦40)...(14) y≦-400x+56000 (40<x≦50)...(15) y≦-1300x+101000 (50<x≦60)...(16) y≧-280x+8300 (10≦x≦20)...(17) y≧-180x+6300 (20<x≦30)...(18) y ≥ 150x - 3600 (30 < x ≤ 40) ... (19) y ≥ 760x - 28000 (40 < x ≤ 50) ... (20) y ≥ 700x - 25000 (50 < x ≤ 60) ... (21)

13. A manufacturing method according to any one of claims 1 to 10, comprising the step of determining the amount of oil and the amount of thickener such that the amount of oil x (mass%) and the viscosity y (mPa·s) of the emulsion composition satisfy the following relational formulas (22), (23), (24), (25), or (26) and relational formulas (27), (28), (29), (30), or (31). (Relational expression) y≦-1640x+152200 (10≦x≦20)...(22) y≦-5295x+225300 (20<x≦30)...(23) y≦-3546x+172830 (30<x≦40)...(24) y≦-281x+42230 (40<x≦50)...(25) y≦-718x+64080 (50<x≦60)...(26) y≧-324.3x+9345 (10≦x≦20)...(27) y≧-186.6x+6591 (20<x≦30)...(28) y≧-153.3x-3606 (30<x≦40)...(29) y≧-900.4x-33490 (40<x≦50)...(30) y ≥ 847x - 30820 (50 < x ≤ 60) ... (31)

14. A manufacturing method according to any one of claims 1 to 10, comprising the step of determining the amount of oil and the concentration of carboxyvinyl polymer such that the amount of oil x (mass%) and the concentration of carboxyvinyl polymer y (mass%) satisfy the following relational equations (32), (33), or (34), and also satisfy the relational equations (35), (36), or (37). (Relational expression) y ≤ -0.0725x + 2.525 (10 ≤ x ≤ 30) ... Relational expression (32) y ≤ -0.02x + 0.95 (30 < x ≤ 40) ... Relational expression (33) y ≤ -0.0056x + 0.374 (40 < x ≤ 60) ... Relational expression (34) y ≥ -0.0024x + 0.104 (10 ≤ x ≤ 30) ... Relational expression (35) y ≥ -0.032 (30 < x ≤ 50) ... Relational expression (36) y ≥ -0.001x + 0.082 (50 < x ≤ 60) ... Relational expression (37)

15. The manufacturing method according to any one of claims 1 to 14, wherein the emulsification step is performed at a temperature of 5°C to 40°C.

16. The manufacturing method according to any one of claims 1 to 15, wherein the emulsified composition substantially contains no humectant.

17. The manufacturing method according to claim 16, wherein the humectant is selected from polyethylene glycol, erythritol, sorbitol, xylitol, and maltitol.

18. The manufacturing method according to claim 16 or 17, wherein "substantially free of humectants" means that the amount of humectant added is 0.3% by mass or less relative to the total amount of the emulsified composition.

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