JP7652487B2 - Skin cleansing composition - Google Patents

Description

The present invention relates to a skin cleansing composition.

Skin cleansing compositions such as body soaps and hand soaps are required to have excellent moisturizing properties and to improve the condition of the skin after cleansing. In order to achieve excellent moisturizing properties, it is possible to solve the problem of moisturizing ingredients not remaining sufficiently on the skin due to being washed away during rinsing, and to improve foam performance such as the creaminess of the foam and the amount of foam, which are important properties for providing a moisturizing feeling. Also, in order to improve the condition of the skin after cleansing, it is possible to impart a moist feeling after cleansing and improve the skin texture.

In recent years, a skin cleanser composition has been proposed which, by blending a fatty acid salt, provides good cleansing power, foam elasticity, foam durability, and deodorizing power durability, and which, by blending at least one selected from highly branched cyclic dextrins and hydroxyalkylated cyclodextrins, and at least one selected from amphoteric surfactants and alkylamine oxides, improves the moist feeling of the skin after cleansing (see, for example, Patent Document 1).
In addition, a liquid skin cleansing composition has been proposed that contains a higher fatty acid and a cationic polymer to improve the amount of foam, the creaminess of the foam, and the moist feeling of the skin after towel drying (see, for example, Patent Document 2).

However, while conventional skin cleansing compositions have good moisturizing properties because they can increase the amount of moisture remaining on the skin after cleansing and provide a moist feeling, there is an issue that the condition of the skin after cleansing, particularly the condition (texture) of the skin, is not fully satisfactory.

Therefore, a skin cleansing composition that maintains good foaming performance while leaving skin in good condition after cleansing has not yet been provided, and there is currently a strong demand for its prompt development.

International Publication No. 2016/093089 International Publication No. 2018/100876

The present invention aims to solve the above-mentioned problems and achieve the following objectives. That is, the present invention aims to provide a skin cleansing composition that can improve the texture of the skin after cleansing while maintaining good foam retention and moisturizing the skin after towel drying.

As a result of intensive research conducted by the inventors to achieve the above object, it has been discovered that a foam containing (A) an anionic surfactant, (B) at least one cationic polymer selected from dimethyldiallylammonium chloride polymer and dimethyldiallylammonium chloride-acrylic acid copolymer, and (C) creatinine, in which the molar ratio of structural units derived from dimethyldiallylammonium chloride in the dimethyldiallylammonium chloride-acrylic acid copolymer is 40 mol% or more, and the mass ratio [(A)/(C)] of the content of the anionic surfactant (A) to the content of the creatinine (C) is 206 or more and 625 or less, can improve the texture of the skin after cleansing while maintaining good lather retention and moist feeling of the skin after towel drying.

The present invention is based on the findings of the present inventors, and the means for solving the above problems are as follows.
<1> (A) an anionic surfactant,
(B) at least one cationic polymer selected from a dimethyldiallylammonium chloride polymer and a dimethyldiallylammonium chloride-acrylic acid copolymer;
(C) creatinine,
the molar ratio of structural units derived from dimethyldiallylammonium chloride in the dimethyldiallylammonium chloride-acrylic acid copolymer is 40 mol% or more;
The skin cleansing composition is characterized in that the mass ratio [(A)/(C)] of the content of the anionic surfactant (A) to the content of the creatinine (C) is 206 or more and 625 or less.
<2> The content of the anionic surfactant (A) is 12% by mass or more and 28% by mass or less, based on the total mass of the skin cleanser composition,
The content of the (B) cationic polymer is 0.4% by mass or more and 2% by mass or less based on the total mass of the skin cleanser composition,
The skin cleanser composition according to <1>, wherein the content of the (C) creatinine is 0.04 mass% or more and 0.13 mass% or less, based on the total mass of the skin cleanser composition.
<3> The anionic surfactant (A) contains potassium laurate and potassium myristate,
The content of the potassium laurate is 4% by mass or more and 10% by mass or less based on the total mass of the skin cleanser composition,
The skin cleanser composition according to <1>, wherein the content of the potassium myristate is 8% by mass or more and 12% by mass or less, based on the total mass of the skin cleanser composition.

The present invention can solve the above-mentioned problems of the past and achieve the above-mentioned objective, and provide a skin cleansing composition that can improve the texture of the skin after cleansing while maintaining good foam retention and moisturizing the skin after towel drying.

(Skin cleansing composition)
The skin cleanser composition of the present invention contains (A) an anionic surfactant, (B) at least one cationic polymer selected from a dimethyldiallylammonium chloride polymer and a dimethyldiallylammonium chloride-acrylic acid copolymer, and (C) creatinine, and may further contain other components, as necessary.
In this specification, (A) the anionic surfactant may be referred to as "component (A)", (B) at least one cationic polymer selected from a dimethyldiallylammonium chloride polymer and a dimethyldiallylammonium chloride-acrylic acid copolymer may be referred to as "component (B)", and (C) creatinine may be referred to as "component (C)".

<(A) Anionic Surfactant>
The (A) anionic surfactant is contained in order to improve the amount of foam, foam elasticity, foam retention, and skin smoothness during rinsing.

The component (A) is not particularly limited and may be appropriately selected depending on the purpose, and examples thereof include higher fatty acid salts, polyoxyethylene (POE) alkyl ether sulfates, ether carboxylates, amino acid surfactants, acyltaurine surfactants, sulfosuccinate surfactants, alkyl phosphate surfactants, olefin sulfonates, etc. Among these, from the viewpoint of improving foam retention and skin smoothness during rinsing, higher fatty acid salts, polyoxyethylene (POE) alkyl ether sulfates, ether carboxylates, and amino acid surfactants are preferred, and higher fatty acid salts are more preferred.
These may be used alone or in combination of two or more.

- Higher fatty acid salts -
The higher fatty acid salt is not particularly limited and may be appropriately selected depending on the purpose, and examples thereof include laurate, myristate, palmitate, stearate, etc. Among these, from the viewpoint of improving foam retention and smoothness of the skin during rinsing, higher fatty acid salts containing all of laurate, myristate, palmitate, and stearate are preferred, and higher fatty acid salts containing all of laurate, myristate, and palmitate are more preferred.
These may be used alone or in combination of two or more.

The salt in the higher fatty acid salt is not particularly limited and can be appropriately selected depending on the purpose. Examples of the salt include alkali metal, ammonium, alkanolamine, and basic amino acid salts.
--Alkaline metals--
The alkali metal is not particularly limited and may be appropriately selected depending on the purpose, and examples thereof include sodium, potassium, etc. Among these, potassium is preferred from the viewpoints of improving foam retention and smoothness of the skin during rinsing.

--Alkanolamine--
Examples of the alkanolamine include monoethanolamine, diethanolamine, triethanolamine, triisopropanolamine, 2-amino-2-methylpropanol, and 2-amino-2-methylpropanediol.

--Basic amino acids--
The basic amino acid is not particularly limited and can be appropriately selected depending on the purpose. Examples of the basic amino acid include lysine and arginine.

The content of the laurate salt is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 2% by mass or more and 12% by mass or less, and more preferably 4% by mass or more and 10% by mass or less, based on the total mass of the skin cleanser composition. When the content of the laurate salt is 2% by mass or more, based on the total mass of the skin cleanser composition, a skin cleanser composition that exhibits good foam retention can be obtained. When the content of the laurate salt is 12% by mass or less, based on the total mass of the skin cleanser composition, a skin cleanser composition that provides good skin smoothness during rinsing can be obtained.

The content of the myristate salt is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 3% by mass or more and 14% by mass or less, and more preferably 8% by mass or more and 12% by mass or less, based on the total mass of the skin cleanser composition. When the content of the myristate salt is 3% by mass or more, based on the total mass of the skin cleanser composition, a skin cleanser composition that exhibits good foam retention can be obtained. When the content of the myristate salt is 14% by mass or less, based on the total mass of the skin cleanser composition, a skin cleanser composition that provides good skin smoothness during rinsing can be obtained.

The total content of the higher fatty acid salts contained in the skin cleanser composition of the present invention is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 5% by mass or more and 32% by mass or less, and more preferably 12% by mass or more and 28% by mass or less, based on the total mass of the skin cleanser composition. When the total content of the higher fatty acid salts is 5% by mass or more, based on the total mass of the skin cleanser composition, a skin cleanser composition exhibiting good foam retention can be obtained. When the total content of the higher fatty acid salts is 32% by mass or less, based on the total mass of the skin cleanser composition, a skin cleanser composition that provides good skin smoothness during rinsing can be obtained.

The higher fatty acid salt may be appropriately synthesized or may be a commercially available product.
The method for synthesizing the higher fatty acid salt is not particularly limited and may be appropriately selected depending on the purpose. For example, a fatty acid salt obtained by a conventional method may be blended as it is, or the fatty acid salt may be synthesized by neutralizing a higher fatty acid with an alkali such as potassium hydroxide in a blending tank during the blending process of the skin cleanser composition.

Examples of commercially available products of the higher fatty acid salts include NIKKOL potassium laurate LK-120 (potassium laurate), NIKKOL potassium myristate MK-140 (potassium myristate), TYSORP MNK-40 (potassium coconut oil fatty acid) (all manufactured by Nikko Chemicals Co., Ltd.), NONSARL PK-1 (potassium palmitate) (manufactured by NOF Corp.), and NAA-180 (stearic acid) (manufactured by NOF Corp.).

-Polyoxyethylene (POE) alkyl ether sulfate-
The polyoxyethylene alkyl ether sulfate is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include compounds represented by the following general formula (A1): The polyoxyethylene alkyl ether sulfate may be used alone or in combination of two or more kinds.

In the general formula (A1), R ⁷ represents an alkyl group, and the alkyl group moiety preferably has 10 to 14 carbon atoms.
In the general formula (A1), n represents the average number of moles of ethylene oxide (EO) added, and the average number of moles of ethylene oxide added is preferably 1 to 5.
In the general formula (A1), X represents an alkali metal or ammonium.
The alkali metal is not particularly limited and can be appropriately selected depending on the purpose. Examples of the alkali metal include sodium and potassium.

Specific examples of the polyoxyethylene alkyl ether sulfate include polyoxyethylene (1) sodium lauryl ether sulfate, polyoxyethylene (2) sodium lauryl ether sulfate (also known as POE (2) sodium laureth sulfate), polyoxyethylene (3) sodium lauryl ether sulfate (also known as POE (3) sodium laureth sulfate), polyoxyethylene (4) sodium lauryl ether sulfate, polyoxyethylene (5) sodium lauryl ether sulfate, polyoxyethylene (3) sodium alkyl (C12,13) ether sulfate, polyoxyethylene (2) lauryl ether ammonium sulfate, and polyoxyethylene (3) lauryl ether ammonium sulfate.
The numbers in the parentheses indicate the average number of moles (n) of ethylene oxide added.

The polyoxyethylene alkyl ether sulfate may be a suitably synthesized product or a commercially available product.
Examples of commercially available polyoxyethylene alkyl ether sulfates include Texapon (registered trademark) N70 (polyoxyethylene (2) lauryl ether sodium sulfate) (manufactured by BASF Corporation) and Shinorin SPE-1250 (POE lauryl ether sodium sulfate (2E.O)) (manufactured by New Japan Chemical Co., Ltd.).

-Ether carboxylate-
The ether carboxylate is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include compounds represented by the following general formula (A2) or (A3): The ether carboxylate surfactant may be used alone or in combination of two or more kinds.

In the general formulae (A2) and (A3), ^R8 represents a linear or branched alkyl or alkenyl group having 5 to 23 carbon atoms, or a phenyl group substituted with a linear or branched alkyl or alkenyl group having 5 to 23 carbon atoms, and the number of carbon atoms in the ^R8 portion is preferably 10 to 14.
In the general formula (A2), R ⁹ may be the same or different and represents an alkylene group having 2 to 4 carbon atoms, preferably 2 carbon atoms.
In the general formula (A2), o represents an average added mole number of alkylene oxide of 1 to 20, and the average added mole number of alkylene oxide is preferably 1 to 5.
In the general formulae (A2) and (A3), M ¹ represents a hydrogen atom, an alkali metal, an alkaline earth metal, ammonium, or a basic amino acid.

Specific examples of the ether carboxylate represented by the general formula (A2) or (A3) include polyoxyethylene (3) sodium lauryl ether acetate, polyoxyethylene (4) potassium lauryl ether acetate, and sodium lauryl glycol acetate.
The numerical value in the parentheses indicates the average number of moles (o) of alkylene oxide added.

The ether carboxylic acid surfactant may be a suitably synthesized product or a commercially available product.
Examples of commercially available ether carboxylic acid surfactants include Energicol EC-30 (polyoxyethylene lauryl ether sodium acetate) (manufactured by Lion Specialty Chemicals Co., Ltd.), Viewlite LCA-25F (polyoxyethylene lauryl ether sodium acetate), Viewlite LCA-30D (polyoxyethylene lauryl ether sodium acetate), Viewlite LCA-H (polyoxyethylene lauryl ether acetic acid), Viewlite LCA-25NH (laureth-4 carboxylic acid), Viewlite SHAA (sodium lauryl glycol carboxylate), Viewlite LCA (polyoxyethylene lauryl ether sodium acetate) (all manufactured by Sanyo Chemical Industries, Ltd.), Kao Akipo RLM-45NV (polyoxyethylene (4.5) lauryl ether sodium acetate), and Kao Akipo RLM-100NV (polyoxyethylene (10) lauryl ether sodium acetate) (all manufactured by Kao Corporation).
The numerical value in the parentheses indicates the average number of moles (o) of alkylene oxide added.

- Amino acid-based surfactants -
The amino acid surfactant in the component (A) is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include compounds represented by the following general formula (A4): The amino acid surfactant may be used alone or in combination of two or more kinds.

In the general formula (A4), R ¹⁰ represents a linear or branched alkyl group or alkenyl group having 5 to 23 carbon atoms, or a phenyl group substituted with a linear or branched alkyl group or alkenyl group having 5 to 23 carbon atoms, and the number of carbon atoms in the R ¹⁰ portion is preferably 8 to 18.
In the general formula (A4), R ¹¹ represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.
In the general formula (A4), R ¹² and R ¹³ may be the same or different and each represents a hydrogen atom or -(CH ₂ ) _m ^-COOM2 .
In the general formula (A4), m and n may be the same or different and represent a number from 0 to 20.
In the general formula (A4), M ¹ and M ² may be the same or different and each represents a hydrogen atom, an alkali metal, an alkaline earth metal, ammonium, or a basic amino acid.

The amino acid structure of the hydrophilic portion of the amino acid surfactant is not particularly limited and can be appropriately selected depending on the purpose, but glycine, glutamic acid, and methylalanine are preferred.

Specific examples of amino acid surfactants represented by the general formula (A4) include N-acyl-glycine and its salts, such as N-cocoyl-glycine potassium (N-coconut oil fatty acid acylglycine potassium); N-acyl-N-carboxyethyl-glycine and its salts, such as N-myristoyl-N-carboxyethyl-glycine sodium; N-acylglutamic acid and its salts, such as N-myristoyl-L-glutamate sodium, N-myristoyl-L-glutamate potassium, N-coconut oil fatty acid acyl-L-glutamate potassium, N-palm fatty acid acyl-L-glutamate sodium, and N-stearoyl-L-glutamate sodium; and N-lauroyl-N-methyl-β-alanine potassium.

The amino acid-based surfactant may be appropriately synthesized or may be a commercially available product.
Commercially available amino acid surfactants include, for example, Amirite (registered trademark) GCK-11 (potassium N-coconut oil fatty acid acylglycine), Amirite (registered trademark) GCK-12K (potassium N-coconut oil fatty acid acylglycine), Amirite (registered trademark) GCS-12K (sodium N-coconut oil fatty acid acylglycine), Amirite (registered trademark) GCS-11 (sodium N-coconut oil fatty acid acylglycine), Amisoft (registered trademark) CS-11 (sodium N-myristoyl-L-glutamate), Amisoft (registered trademark) CS-22 (sodium N-coconut oil fatty acid acyl-L-glutamate), Amisoft (registered trademark) LS-11 (N-lauroyl-L-glutamate), Amisoft (registered trademark) CS-22 (sodium N-coconut oil fatty acid acyl-L-glutamate), Amisoft (registered trademark) LS ... sodium glutamate), Amisoft® MS-11 (N-myristoyl-L-sodium glutamate), Amisoft® HS-11P (N-stearoyl-L-sodium glutamate), Amisoft® HS-11P(F) (N-stearoyl-L-sodium glutamate), Amisoft® HS21 (N-stearoyl-L-disodium glutamate), Amirite® ACS-12 (sodium cocoyl alanine) (all manufactured by Ajinomoto Healthy Supply Co., Ltd.), AminoSurfact® AMMS-P1 (N-myristoyl-L-sodium glutamate) (manufactured by Asahi Kasei Chemicals Corporation), NIKKOL Examples of the active ingredient include Sarcosinate MN (sodium myristoyl methylaminoacetate), NIKKOL Alaninate LN-30 (sodium lauroyl methyl-β-alanine) (manufactured by Nikko Chemicals Co., Ltd.), Alanone ACE (sodium coconut oil fatty acid methylalanine), Alanone AME (sodium myristoyl methyl-β-alanine), Alanone ALE (sodium lauroyl methyl-β-alanine) (manufactured by Kawaken Fine Chemicals Co., Ltd.), Energicole L-30AN (sodium lauroyl methyl-β-alanine) (manufactured by Lion Specialty Chemicals Co., Ltd.), Softilt AT-L (sodium lauroyl methyl-β-alanine) (manufactured by NOF Corporation), and Diapon-SF (sodium coconut oil fatty acid methyl taurate) (manufactured by NOF Corporation).

The total content of the anionic surfactants contained in the skin cleanser composition of the present invention is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 5% by mass or more and 32% by mass or less, and more preferably 12% by mass or more and 28% by mass or less, based on the total mass of the skin cleanser composition. When the total content of the anionic surfactants is 5% by mass or more, based on the total mass of the skin cleanser composition, a skin cleanser composition that exhibits good foam retention can be obtained. When the total content of the anionic surfactants is 32% by mass or less, based on the total mass of the skin cleanser composition, a skin cleanser composition that provides good skin smoothness during rinsing can be obtained.

<(B) Cationic polymer>
The cationic polymer is at least one selected from a dimethyldiallylammonium chloride polymer and a dimethyldiallylammonium chloride-acrylic acid copolymer, and by blending it together with the component (A), it is possible to improve the moist feeling of the skin after towel drying and its duration. The component (B) may be used alone or in combination of two or more kinds.
The dimethyldiallylammonium chloride-acrylic acid copolymer in the component (B) is represented by the following general formula (B1).

In the general formula (B1), n and m represent the molar ratio (mol %) of each structural unit.
In the general formula (B1), n is 0 to 35, m is 40 to 100, and n and m satisfy the following formula (I).
n+m=100...Formula (I)

In the present invention, the molar ratio of structural units derived from dimethyldiallylammonium chloride in the dimethyldiallylammonium chloride-acrylic acid copolymer is 40 mol % or more. By having the molar ratio of structural units derived from dimethyldiallylammonium chloride in the dimethyldiallylammonium chloride-acrylic acid copolymer be 40 mol % or more, problems such as insufficient moist feeling on the skin after towel drying and its duration can be solved.
In addition, the molar ratio of structural units derived from dimethyldiallylammonium chloride in the dimethyldiallylammonium chloride-acrylic acid copolymer is preferably 65 mol% or more, and more preferably 95 mol% or more, from the viewpoint of improving the moist feeling of the skin after towel drying and its duration.
The dimethyldiallylammonium chloride-acrylic acid copolymer may be used alone or in combination of two or more kinds.

The content of the (B) component is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 0.2% by mass or more and 3% by mass or less, and more preferably 0.4% by mass or more and 2% by mass or less, based on the total mass of the skin cleanser composition. When the content of the (B) component is 0.2% by mass or more based on the total mass of the skin cleanser composition, a skin cleanser composition that provides a moist feeling on the skin after towel drying can be obtained. When the content of the (B) component is 3% by mass or less based on the total mass of the skin cleanser composition, a skin cleanser composition that provides good smoothness on the skin when rinsing can be obtained.

The weight average molecular weight of the (B) component is not particularly limited and can be appropriately selected depending on the purpose. From the viewpoint of improving the moist feeling of the skin after towel drying and maintaining the moist feeling, the weight average molecular weight is preferably from 10,000 to 1,000,000, and more preferably from 15,000 to 450,000.
The weight average molecular weight of the cationic polymer of the component (B) can be measured, for example, by a SEC-MALLS-RI system (measurement conditions: column: TSKgel α series α-M column 30 cm manufactured by Tosoh Corporation, solvent: 0.3 M aqueous sodium nitrate solution).

When the solid content of the component (B) is 30% by mass or more and 44% by mass or less, the viscosity at 25° C. is preferably 10 mPa·s or more and 15,000 mPa·s or less, and more preferably 20 mPa·s or more and 12,000 mPa·s or less.
The viscosity can be measured, for example, by using a Brookfield viscometer LVF (manufactured by Brookfield Corporation).

The cationic polymer of the component (B) may be one that is appropriately synthesized or a commercially available product.
Examples of commercially available products of the component (B) include Merquat 100, Merquat 106, Merquat 295, and Merquat 280 (all manufactured by Lubrizol Corporation). Among these, Merquat 100, Merquat 106, and Merquat 295 are preferred from the viewpoint of improving the moist feeling of the skin after towel drying.

The composition and physical properties of each commercially available product are shown below.
-Marquardt 100-
Composition (molar ratio) Acrylic acid: dimethyldiallylammonium chloride = 0:100
・Solid content: 39% by mass to 44% by mass
Viscosity at 25°C: 8,000 mPa·s to 12,000 mPa·s
・Weight average molecular weight 150,000
The viscosity can be measured using a Brookfield viscometer LVF (manufactured by Brookfield Corporation) at 25° C. with a spindle No. 3 rotor at 6 revolutions per minute.
-Marquardt 106-
Composition (molar ratio) Acrylic acid: dimethyldiallylammonium chloride = 0:100
・Solid content 30% to 36% by mass
Viscosity at 25°C: 20mPa·s to 65mPa·s
・Weight average molecular weight 15,000
The viscosity can be measured using a Brookfield viscometer LVF (manufactured by Brookfield Corporation) at 25° C. with a spindle No. 3 rotor at 6 revolutions per minute.
-Marquardt 295-
Composition (molar ratio) Acrylic acid: dimethyldiallylammonium chloride = 5:95
・Solid content 35% to 40% by mass
・Viscosity at 25℃: 3,500mPa・s to 9,000mPa・s
・Weight average molecular weight 150,000
The viscosity can be measured using a Brookfield viscometer LVF (manufactured by Brookfield Corporation) at 25° C. with a rotor of spindle No. 4 at 30 revolutions per minute.
-Marquardt 280-
Composition (molar ratio) acrylic acid: dimethyldiallylammonium chloride = 35:65
・Solid content: 39% by mass to 43% by mass
Viscosity at 25°C: 3,000 mPa·s to 6,000 mPa·s
・Weight average molecular weight 450,000
The viscosity can be measured using a Brookfield viscometer LVF (manufactured by Brookfield Corporation) at 25° C. with a spindle No. 4 rotor at 30 rpm.

The molar ratio of each structural unit in the dimethyldiallylammonium chloride-acrylic acid copolymer can be measured by nuclear magnetic resonance (NMR) under the following measurement conditions.
[Measurement conditions]
Solvent: heavy water ( _D2O )
Measuring instrument: JNM-LA300 (300MHz, manufactured by JEOL Ltd.)

<(C) Creatinine>
The (C) creatinine is added to improve skin texture.

The content of the (C) creatinine is not particularly limited and may be appropriately selected depending on the purpose, but is preferably 0.01% by mass or more and 0.15% by mass or less, and more preferably 0.04% by mass or more and 0.13% by mass or less, based on the total mass of the skin cleanser composition. When the (C) creatinine content is 0.01% by mass or more, based on the total mass of the skin cleanser composition, a skin cleanser composition that provides good skin texture can be obtained. When the (C) creatinine content is 0.15% by mass or less, based on the total mass of the skin cleanser composition, a skin cleanser composition that exhibits good foam retention can be obtained.

The creatinine (C) used may be an appropriately synthesized product or a commercially available product.
Examples of commercially available products of the (C) creatinine include TEGO Cosmo C 250 (manufactured by Evonik Corporation) and creatinine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

<Mass ratio [(A)/(C)]>
In the present invention, the mass ratio [(A)/(C)] of the content of the component (A) to the content of the component (C) is 206 or more and 625 or less. When the mass ratio [(A)/(C)] of the contents is 206 or more, a skin cleanser composition exhibiting good foam retention can be obtained. When the mass ratio [(A)/(C)] of the contents is 625 or less, a skin cleanser composition which provides good skin texture can be obtained.
The mass ratio of the content of the component (A) to the content of the component (C) [(A)/(C)] is preferably 210 or more and 280 or less in terms of good foam retention and good skin texture.

<Other ingredients>
In addition to the component (A), the component (B), and the component (C), other components may be blended into the skin cleansing composition of the present invention, as necessary, within a range that does not impair the effects of the present invention.
Examples of the other components include purified water, surfactants other than the component (A), water-soluble polymers other than the cationic polymer of the component (B), moisturizers, sugars, oils, alcohols such as lower and higher alcohols, lanolin derivatives, protein derivatives, acrylic resin dispersions, medicines such as vitamins, bactericides, preservatives, viscosity adjusters, pH adjusters, antioxidants, sequestering agents, ultraviolet absorbers, animal and plant extracts or derivatives thereof, colorants, fragrances, pigments, inorganic powders, clay minerals, water-insoluble polymer powders such as nylon and polyethylene, etc. These may be used alone or in combination of two or more.
The other components may be appropriately synthesized or commercially available products.
The content of the other components in the skin cleansing composition is not particularly limited and may be appropriately selected depending on the purpose.

<pH>
The pH of the skin cleansing composition at 25° C. is preferably from 9.0 to 11.0, and more preferably from 9.3 to 10.6, in terms of increasing the amount of foam.
The pH can be measured, for example, using a pH meter (HM-30R, manufactured by TOA DKK Corporation).

<Viscosity>
The viscosity of the skin cleansing composition at 25° C. is not particularly limited and may be appropriately selected depending on the purpose, but is preferably from 1 mPa·s to 6,000 mPa·s, and more preferably from 50 mPa·s to 4,000 mPa·s.
The viscosity can be measured, for example, using a BM type viscometer (manufactured by Tokyo Keiki Co., Ltd.) under the following conditions at a sample temperature of 25° C. If the viscosity is 1 mPa·s or more and 3,000 mPa·s or less, the viscosity can be measured after 1 minute using a BM adapter, a rotation speed of 30 rpm, and a No. 3 rotor, and if the viscosity exceeds 3,000 mPa·s, the viscosity can be measured by using a BM adapter, a rotation speed of 30 rpm, and a No. 4 rotor to measure the viscosity after 1 minute.

<Container>
The container for housing the skin cleansing composition of the present invention is not particularly limited and may be appropriately selected depending on the purpose, but a pump dispenser container or a foamer container is preferred.

- Pump dispenser container -
The pump dispenser container may be, for example, a pump dispenser container manufactured by Yoshino Kogyosho Co., Ltd., having a nozzle diameter (inner diameter) of 3.5 mm and a discharge amount of 3 mL.

-Former container-
The foamer container may be a non-gas type foam-discharging container, which is not particularly limited as long as it can mix the skin cleansing composition of the present invention with air and discharge it in a foamed state, and may be appropriately selected depending on the purpose, and examples thereof include a squeeze foamer container that can discharge foam by squeezing the bottle body by hand, and a pump foamer container that can discharge foam by pressing down the nozzle part.
As the former container, for example, a former container manufactured by Yamato Can Co., Ltd., a former container manufactured by Yoshino Kogyosho Co., Ltd., or the like can be used.

The non-gas type foam discharge container generally has a porous membrane for forming foam, and foam is formed when the skin cleansing composition passes through the porous membrane.
The material of the porous membrane is not particularly limited and can be appropriately selected depending on the purpose, but plastic materials such as nylon, polyester, polyolefin, etc. are preferred.

The mesh of the porous membrane is not particularly limited and can be appropriately selected depending on the purpose, but for example, 100 mesh or more is preferable, 100 mesh or more and 400 mesh or less are more preferable, and 200 mesh or more and 350 mesh or less are even more preferable.

The number of the porous membrane bodies is not particularly limited and can be appropriately selected depending on the purpose, but from the viewpoint of improving foam performance, 2 to 4 sheets are preferable. More specifically, the foamer containers described in JP-A-7-315463, JP-A-8-230961, and JP-A-2005-193972 can be preferably used.

When the skin cleansing composition of the present invention is filled into the foamer container and used, from the viewpoint of foam forming ability, the viscosity at 25°C is preferably 1 mPa·s or more and 20 mPa·s or less, and more preferably 1 mPa·s or more and 10 mPa·s or less. The viscosity can be measured using a BL type viscometer (manufactured by Tokyo Keiki Co., Ltd.) at 25°C using a No. 1 rotor at 60 rpm.

<Production Method>
The method for producing the skin cleanser composition of the present invention is not particularly limited and may be appropriately selected depending on the purpose. The skin cleanser composition of the present invention may be obtained by mixing the (A), (B), and (C) components, and, if necessary, the other components and purified water (blended as the balance so that the total amount of the skin cleanser composition becomes 100% by mass).
Specifically, it can be produced as follows: The component (A) is dissolved in purified water heated to 70°C to 80°C, and the water is cooled to 40°C or lower, and then the components (B) and (C) are added to produce the composition.

The skin cleanser composition may be prepared using an apparatus that is not particularly limited and can be appropriately selected depending on the purpose, and examples thereof include a stirring apparatus equipped with a stirring blade that exerts a shear force and can mix the entire composition.
The stirring blade is not particularly limited and can be appropriately selected depending on the purpose. Examples of the stirring blade include a propeller, a turbine, and a disperser.

<Applications>
The skin cleansing composition of the present invention can be used, for example, as a face wash, hand soap, body soap, cleansing foam, makeup remover, etc., and is particularly suitable for use as a body soap.

The present invention will be described in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples.
The content of each component in the examples and comparative examples is shown in "mass %" and is a value converted into a pure content. The mass ratio of the content of the component (A) to the content of the component (C) [(A)/(C)] is rounded off to the first decimal place and calculated as an integer.

(Examples 1 to 31 and Comparative Examples 1 to 7)
Skin cleansing compositions having the compositions and contents shown in the table below were prepared by the following method.
Purified water in an amount equivalent to 95% by mass of the total amount of the finally obtained skin cleanser composition was heated to 70°C to 80°C to dissolve the anionic surfactant of component (A). The mixture was then cooled to 40°C or lower, and component (B) or a comparative component of component (B), component (C) or a comparative component of component (C), and other components were added to prepare a skin cleanser composition. If the pH did not reach the predetermined value, potassium hydroxide, a common component, was added to adjust the pH to the predetermined value, and purified water was added so that the total amount became 100% by mass to obtain the intended skin cleanser compositions of Examples 1 to 31 and Comparative Examples 1 to 7. The mixture was stirred using a Three-One Motor (HEIDON BL1200; manufactured by Shinto Chemical Co., Ltd.), and a propeller was used as the stirring blade.
The pH of each of the obtained skin cleansing compositions of Examples 1 to 31 and Comparative Examples 1 to 7 was measured at 25° C. using a pH meter (HM-30R; manufactured by TOA DKK Corporation).
The obtained skin cleanser compositions of Examples 1 to 8, Examples 10 to 31, and Comparative Examples 1 to 7 were filled into a container with a pump dispenser (discharge volume 3 mL, nozzle diameter (inner diameter) 3.5 mm, manufactured by Yoshino Kogyosho Co., Ltd.), and the skin cleanser composition of Example 9 was filled into a foamer container (discharge volume 3 mL, manufactured by Yoshino Kogyosho Co., Ltd.).

The obtained skin cleansing compositions of Examples 1 to 31 and Comparative Examples 1 to 7 were evaluated and judged for "foam retention," "skin smoothness during rinsing," "skin moistness after towel drying," and "skin texture." The results are shown in Tables 1 to 6 below.

<Good foam retention>
Ten expert evaluators soaked a nylon towel with one push (about 3 g) of the skin cleansing composition in a container, lathered it 10 times, and washed the whole body. The foam retention was evaluated based on the following evaluation criteria, and an average score was calculated. The obtained average score was judged based on the following judgment criteria.
[Evaluation criteria for foam retention]
5 points: Very good foam retention 4 points: Fairly good foam retention 3 points: Good foam retention 2 points: Poor foam retention 1 point: Poor foam retention [Average score for foam retention]
◎: 4 points or more 〇: 3 points or more but less than 4 points △: 2 points or more but less than 3 points ×: 1 point or more but less than 2 points

<Evaluation of skin smoothness after rinsing>
Ten expert evaluators applied two pumps (about 6 g) of the skin cleansing composition contained in a container to a nylon towel, lathered it 10 times, and washed the whole body. The smoothness of the skin when rinsing was evaluated based on the following evaluation criteria, and the average score was calculated. The obtained average score was judged based on the following judgment criteria.
[Evaluation criteria for skin smoothness when rinsing]
5 points: Skin feels extremely smooth when rinsing 4 points: Skin feels smooth when rinsing 3 points: Skin feels somewhat smooth when rinsing 2 points: Skin does not feel very smooth when rinsing 1 point: Skin does not feel smooth at all when rinsing [Judgment criteria for average score of skin smoothness when rinsing]
◎: 4 points or more 〇: 3 points or more but less than 4 points △: 2 points or more but less than 3 points ×: 1 point or more but less than 2 points

<Evaluation of moisturizing feeling of skin after towel drying>
Ten expert evaluators applied two pumps (about 6 g) of the skin cleansing composition contained in a container to a nylon towel, lathered it 10 times, and washed the whole body. The moist feeling of the skin after towel drying was evaluated based on the following evaluation criteria, and an average score was calculated. The obtained average score was judged based on the following judgment criteria. The evaluation was performed after acclimation for 30 minutes in a room at 25°C and 40% RH.
[Evaluation criteria for moisturizing feeling of skin after towel drying]
5 points: Strongly moisturized feeling 4 points: Moisturized feeling 3 points: Slightly moisturized feeling 2 points: Not very moisturized feeling 1 point: Not moisturized feeling at all (average score for moisturized feeling of skin after towel drying)
◎: 4 points or more 〇: 3 points or more but less than 4 points △: 2 points or more but less than 3 points ×: 1 point or more but less than 2 points

<Skin Texture Evaluation>
Three expert evaluators applied two pumps (about 6 g) of the skin cleansing composition from the container to a nylon towel, lathered it 10 times, and washed the whole body. The skin texture was then evaluated based on the following evaluation criteria, and an average score was calculated. The obtained average score was judged based on the following judgment criteria.
[Skin Texture Evaluation Criteria]
5 points: Very fine grain
4 points: Slightly fine grain
3 points: Neither
2 points: slightly coarse
1 point: Very rough texture [average skin texture score criteria]
◎: 4 points or more 〇: 3 points or more but less than 4 points △: 2 points or more but less than 3 points ×: 1 point or more but less than 2 points

Details of each component used in Examples 1 to 31 and Comparative Examples 1 to 7 are shown in Table 7 below.

The skin cleansing composition of the present invention can improve the texture of the skin after cleansing while maintaining good foam retention and moist feeling after towel drying, and can therefore be used, for example, in facial cleansers, hand soaps, body soaps, cleansing foams, makeup removers, and the like, and is particularly suitable for use in body soaps.

Claims (3)

(A) an anionic surfactant;
(B) at least one cationic polymer selected from a dimethyldiallylammonium chloride polymer and a dimethyldiallylammonium chloride-acrylic acid copolymer;
(C) creatinine,
the molar ratio of structural units derived from dimethyldiallylammonium chloride in the dimethyldiallylammonium chloride-acrylic acid copolymer is 40 mol% or more;
A skin cleansing composition, characterized in that a mass ratio [(A)/(C)] of a content of the anionic surfactant (A) to a content of the creatinine (C) is 206 or more and 625 or less. the content of the anionic surfactant (A) is 12% by mass or more and 28% by mass or less, based on the total mass of the skin cleanser composition;
The content of the (B) cationic polymer is 0.4% by mass or more and 2% by mass or less based on the total mass of the skin cleanser composition,
The skin cleanser composition according to claim 1, wherein the content of the creatinine (C) is 0.04% by mass or more and 0.13% by mass or less, based on the total mass of the skin cleanser composition. The anionic surfactant (A) contains potassium laurate and potassium myristate,
The content of the potassium laurate is 4% by mass or more and 10% by mass or less based on the total mass of the skin cleanser composition,
2. The skin cleanser composition according to claim 1, wherein the content of the potassium myristate is 8% by mass or more and 12% by mass or less, based on the total mass of the skin cleanser composition.