JP2023007391A - Composition containing cationic group-containing polymer - Google Patents

Abstract

To provide a composition that is excellent in antiseptic antibacterial properties, solubility in water, and storage stability when dissolved in water.SOLUTION: A composition contains a polymer (A) having a cationic group-containing monomer-derived structural unit and a hydrophobic monomer-derived structural unit, and an acid. The total amount of the acid relative to 1 mol of the cationic group is 0.10 mol% or more and 1.50 mol% or less.SELECTED DRAWING: None

Description

The present invention relates to compositions containing cationic group-containing polymers. Compositions containing the cationic group-containing polymer of the present invention can be suitably used as cosmetic compositions such as skin cosmetics, external skin preparations and hair cosmetics.

In recent years, from the point of view of consumers' preference for cleanliness and hygiene, various antibacterial products have been marketed. Various antibacterial agents have been developed for use in antibacterial processed products, and inorganic and organic antibacterial agents have been developed. In Patent Document 1, an antibacterial agent containing a cationic group-containing polymer, the polymer has a structural unit derived from a cationic group-containing monomer and a structural unit derived from a hydrophobic monomer, The ratio of structural units derived from the cationic group-containing monomer is 36 to 99.9% by mass with respect to 100% by mass of all structural units, the weight average molecular weight is 4000 to 1,000,000, and the hydrophobic unit The antibacterial agent includes a cationic group-containing polymer characterized in that the polymer has a solubility parameter of 15 or less for the homopolymer.

JP 2017-214346 A

When the antibacterial agent is used as a cosmetic additive such as a skin lotion, the polymer described in Patent Document 1 has a hydrophobic group, so the solubility in water may be insufficient. Neutralization with an acid is considered to improve the solubility in water, but storage stability of the neutralized aqueous solution has also been desired.

The inventors conducted studies in view of the above problems, and obtained a polymer (A) having a structural unit derived from a cationic group-containing monomer and a structural unit derived from a hydrophobic monomer, and an acid. , The composition in which the total amount of acid relative to 1 mol of the cationic group is 0.10 mol% or more and 1.50 mol% or less is excellent in antiseptic antibacterial properties when used as a cosmetic, and has good solubility in water. The present inventors have also found that they are excellent in terms of storage stability when dissolved in water, and have completed the present invention.

According to the present invention, it is possible to provide a composition having excellent antiseptic and antibacterial properties, excellent water solubility, and excellent storage stability when dissolved in water. Furthermore, it is possible to provide a cosmetic composition that suppresses stickiness and provides a moist feeling.

The present disclosure will now be described in detail.
The composition of the present disclosure contains a polymer (A) having a structural unit derived from a cationic group-containing monomer and a structural unit derived from a hydrophobic monomer, and an acid. The total amount is 0.10 mol % or more and 1.50 mol % or less.
The polymer (A) of the present disclosure has a structural unit derived from a cationic group-containing monomer and a structural unit derived from a hydrophobic monomer.
The structural unit derived from the cationic group-containing monomer of the present disclosure may have the same structure as the structure in which at least one carbon-carbon double bond of the cationic group-containing monomer is replaced with a carbon-carbon single bond, It is not limited to structural units formed by polymerization of cationic group-containing monomers, and may be structural units formed by post-reaction after polymerization, for example.
A structural unit derived from a cationic group-containing monomer of the present disclosure is a structural unit derived from a monomer containing a cationic group.

The cationic group of the present disclosure is a group having a cation or a group that generates a cation, and is not particularly limited, and examples thereof include primary to tertiary amino groups, quaternary ammonium bases, and the like. Among the primary to tertiary amino groups and quaternary ammonium bases, the cationic group is preferably a tertiary amino group or a quaternary ammonium base, from the viewpoint of having antibacterial properties and reducing skin irritation. A tertiary amino group is more preferred. From the viewpoint of skin irritation, it may be a primary to tertiary amino group.

<Primary to Tertiary Amino Groups>
As the primary to tertiary amino groups, the following formula (1);

(wherein R ₁ and R ₂ are the same or different and represent a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms). The hydrocarbon group is preferably an alkyl group, an alkenyl group, or an aryl group, more preferably an alkyl group or an alkenyl group, and still more preferably an alkyl group. The number of carbon atoms in the hydrocarbon group is preferably 1-10, more preferably 1-8, particularly preferably 1-5, and most preferably 1-2.
At least one of R ₁ and R ₂ is preferably a hydrocarbon group having 1 to 12 carbon atoms, and both R ₁ and R ₂ are preferably hydrocarbon groups having 1 to 12 carbon atoms. more preferred. Among primary to tertiary amino groups, tertiary amino groups are preferred. A dimethylamino group and a diethylamino group are preferable as the tertiary amino group.

<Quaternary ammonium base>
As the quaternary ammonium base, the following formula (2);

(wherein R ₃ to R ₅ are the same or different and represent a hydrocarbon group having 1 to 12 carbon atoms). The hydrocarbon group is preferably an alkyl group, an alkenyl group, or an aryl group, more preferably an alkyl group or an alkenyl group, and still more preferably an alkyl group. The number of carbon atoms in R ₃ to R ₅ is preferably 1-10, still more preferably 1-7, and particularly preferably 1-5.
A methyl group or an ethyl group is most preferable as the hydrocarbon group for R ₃ to R ₅ .

<Monomer containing cationic group>
In the present disclosure, the cationic group-containing monomer includes, for example, a monomer containing the above primary to tertiary amino groups in its structure and a monomer containing a quaternary ammonium base in its structure. Specifically, N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, N,N-diethylaminopropyl (meth)acrylate N,N-dialkylamino group-containing (meth)acrylates such as and monomers obtained by adding a quaternizing agent to the above monomers or neutralized products thereof with acids; N,N-dimethylaminoethyl (meth)acrylamide, N ,N-diethylaminoethyl (meth)acrylamide, N,N-dimethylaminopropyl (meth)acrylamide, N,N-dialkylamino group-containing (meth)acrylamides such as N,N-diethylaminopropyl (meth)acrylamide and the above monomers A monomer obtained by adding a quaternizing agent to or a neutralized product thereof with an acid; ) acrylates, monoalkylamino group-containing (meth)acrylates such as 2-(tert-butylamino)ethyl (meth)acrylate, and neutralized products thereof with acids; monomethylaminoethyl (meth)acrylamide, monoethylaminoethyl Monoalkylamino group-containing (meth)acrylamides such as (meth)acrylamide, monomethylaminopropyl (meth)acrylamide, monoethylaminopropyl (meth)acrylamide and neutralized products thereof with acids; (meth)acrylic acid-2- Esters of (meth)acrylic acid such as aminoethyl and alkanolamine, and neutralized products thereof; hydrates; neutralized products with allylamine and these acids; cyclic ether-containing groups having 2 to 8 carbon atoms such as 1-allyloxy-3-dibutylamino-2-ol and 1-allyloxy-3-diethanolamino-2-ol and an amine compound having 1 to 24 carbon atoms, a monomer obtained by adding a quaternizing agent thereto, or a neutralized product thereof with an acid. In particular N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylate, N,N-diethylaminopropyl (meth)acrylate and the like. N-dialkylamino group-containing (meth)acrylates, monomers obtained by adding a quaternizing agent to the above monomers, or neutralized products thereof with acids are preferred.

<Hydrophobic monomer>
In the present disclosure, a structural unit derived from a hydrophobic monomer represents a structural unit having the same structure as the structure formed by polymerizing the hydrophobic monomer. That is, the structural unit derived from the hydrophobic monomer is not limited to the structural unit actually formed by polymerizing the hydrophobic monomer, and as long as it has the same structure, the structural unit formed by a different production method. is included in structural units derived from hydrophobic monomers. For example, a structural unit derived from methyl acrylate, CH2=CH(-COOCH3), can be represented by -CH2-CH(-COOCH3)-.
The hydrophobic monomer preferably has a solubility parameter of 15 or less with respect to a homopolymer obtained by homopolymerization. A monomer having a cationic group and containing a quaternary ammonium base is included in the cationic group-containing monomer even if the solubility parameter is 15 or less.

The solubility parameter of the present disclosure is a value calculated by the method described in "POLYMER ENGINEERING AND SCIENCE" (1974, Vol. 14, No. 2) pp. 147-154.
The method is outlined below. The solubility parameter (δ) (cal/cm3) 1/2 of the homopolymer is calculated as follows based on the evaporation energy (Δei) and molar volume (Δvi) of the constituent units forming the homopolymer. calculated by the method.
δ = (Δei/Δvi) 1/2 (cal/cm3) 1/2
If the solubility parameter of the homopolymer obtained by polymerizing the hydrophobic monomer alone is 15 or less, the hydrophobicity of the polymer of the present invention is sufficient, and the affinity for bacterial cell membranes is high. By inhibiting the physiological activity of the cell membrane, it has excellent antibacterial performance.

Examples of the hydrophobic monomer include esters ((meth)acrylates) of (meth)acrylic acid and an alcohol that may have a substituent (hereinafter also referred to as (meth)acrylic acid esters); Unsaturated monocarboxylic acids such as (meth)acrylic acid, crotonic acid, α-allyloxyacrylic acid and salts thereof; aromatic vinyl monomers such as styrene; olefinic monomers such as ethylene and propylene; acetic acid esters of unsaturated alcohols such as vinyl and carboxylic acids; vinyl halides such as vinyl chloride; alkyl vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; Addition products of unsaturated monomers having 8 cyclic ether-containing groups and alcohols having 1 to 20 carbon atoms; carbon such as ethylene oxide adducts of allyl alcohol, ethylene oxide adducts of methallyl alcohol, ethylene oxide adducts of isoprenol, etc. Alkylene oxide adducts of unsaturated alcohols of number 2 to 20 and their terminal hydrophobically modified products; and cyclic vinyl-based monomers such as N-vinylpyrrolidone. As the hydrophobic monomer, one having an alkyl group having 2 or more carbon atoms is preferable. When the hydrophobic monomer has an alkyl group having 2 or more carbon atoms, the affinity with the cell membrane of microorganisms is increased, and the antibacterial properties are further improved.
Examples of the unsaturated monocarboxylic acid salts include metal salts. Alkali metals, such as lithium, sodium, potassium, are mentioned as a metal of the said metal salt.
Examples of substituents in the (meth)acrylate include hydroxyl group; alkoxy group having 1 to 18 carbon atoms such as methoxy group and ethoxy group; oxo group-containing group such as oxyalkylene group, sulfonic acid group and phosphoric acid group; fluoro group and the like. a halogeno group; an epoxy group such as a glycidyl group; a carbonyl group such as an aldehyde group.

Examples of alkyl (meth)acrylates having no substituents as described above include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, ) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, sec-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, tridecyl (meth) acrylate, cyclohexyl (meth) acrylate ) acrylate, n-lauryl (meth)acrylate, dodecyl (meth)acrylate, stearyl (meth)acrylate, isobornyl methacrylate and the like.

Examples of hydroxyl group-containing (meth)acrylates include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxy Examples thereof include hydroxyl group-containing (meth)acrylates having an ester group having 1 to 18 carbon atoms, such as butyl (meth)acrylate.
Examples of alkoxyalkyl (meth)acrylates include methoxyethyl (meth)acrylate, methoxypropyl (meth)acrylate, methoxybutyl (meth)acrylate, ethoxybutyl (meth)acrylate, trimethylolpropane tripropoxy (meth)acrylate, and the like. mentioned.
Examples of oxo group-containing (meth)acrylates include (di)ethylene glycol (methoxy) ( meth) acrylate; alkoxy polyalkylene glycol (meth) acrylate having a repeating number of 1 to 100 of alkylene glycol such as alkoxy polyethylene glycol methacrylate (Antox LMA-10); sulfopropyl (meth) acrylate; (meth) acryloyloxyethyl phosphate etc.

Examples of fluoro group-containing (meth)acrylates include fluoro group-containing ester groups having 2 to 6 carbon atoms, such as trifluoroethyl (meth)acrylate, tetrafluoropropyl (meth)acrylate, and octafluoropentyl (meth)acrylate. Alkyl (meth)acrylate and the like can be mentioned.
Examples of epoxy group-containing (meth)acrylates include glycidyl (meth)acrylate, α-methylglycidyl (meth)acrylate, glycidyl allyl ether and the like.
Examples of carbonyl group-containing (meth)acrylates include acetonyl (meth)acrylate, diacetone (meth)acrylate, 2-hydroxypropyl (meth)acrylate acetylacetate, butanediol-1,4-acrylate acetylacetate, 2-(aceto acetoxy)ethyl (meth)acrylate, (meth)acryloyloxyalkylpropenal and the like.

The polymer of the present disclosure preferably contains at least one (meth)acrylic acid ester-derived structural unit as the hydrophobic monomer-derived structural unit. As the structural unit derived from the (meth) acrylic acid ester, the following formula (2);

(Wherein, R5 represents a hydrogen atom or a methyl group.R6 represents a hydrocarbon group having 1 to 30 carbon atoms.)
is preferably a structural unit represented by

In the (meth)acrylic acid ester and the structural unit derived from the (meth)acrylic acid ester, the number of carbon atoms in the hydrocarbon group is preferably 1 to 20, more preferably 1 to 16, and further It is preferably 1-12, and particularly preferably 2-8. When the number of carbon atoms in the hydrocarbon group is 2 to 8, the water solubility and viscosity of the polymer can be within suitable ranges, and the production of the polymer is easy. Furthermore, it is excellent in safety and the antibacterial property is further improved.

The hydrocarbon group is not particularly limited, and includes chain hydrocarbon groups such as alkyl groups, alkenyl groups and alkynyl groups, and cyclic hydrocarbon groups such as aromatic hydrocarbon groups, cycloalkyl groups and cycloalkenyl groups. . The above hydrocarbon group may have a branch, and the number of carbon atoms in the hydrocarbon group in the case of having a branch means the total number of carbon atoms in the main chain and the branched chains. Examples of the alkyl group include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, hexyl group, heptyl group, 2-ethylhexyl group, octyl group, nonyl group, decyl group and dodecyl group. , stearyl group, icosyl group and the like. Examples of the alkenyl group include vinyl group, allyl group, 1-butenyl group, 2-butenyl group, pentenyl group, hexenyl group, heptenyl group, octenyl group, nonenyl group, decenyl group, dodecenyl group, octadecenyl group and icosenyl group. etc. Examples of the alkynyl group include ethynyl group, 1-propynyl group, 2-propynyl group, butynyl group, pentynyl group, hexynyl group, heptynyl group, octynyl group, nonynyl group, decynyl group, dodecynyl group, octadecynyl group and icosinyl group. etc.

Examples of the aromatic hydrocarbon group include phenyl group, benzyl group, tolyl group, o-xylyl group and the like. Examples of the cycloalkyl group include cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group and the like. Examples of the cycloalkenyl group include cyclopropenyl group, cyclobutenyl group, cyclopentenyl group, cyclohexenyl group and the like. The hydrocarbon group is preferably an alkyl group or an alkenyl group, more preferably an alkyl group. That is, as the (meth)acrylic acid ester, (meth)acrylic acid alkyl ester (alkyl (meth)acrylate) is preferable.

Alkyl (meth)acrylates are preferably methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert- butyl (meth) acrylate, sec-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, more preferably methyl (meth) acrylate, ethyl (meth) acrylate, n- Propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, sec-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate be. Especially preferred is ethyl (meth)acrylate.

<Other ingredients>
The polymer of the present disclosure may have structural units derived from monomers other than the cationic group-containing monomer and the hydrophobic monomer. The other monomer is not particularly limited, and the solubility parameter of the homopolymer of the other monomer may be 15 or less or more than 15. Even if the solubility parameter of the other monomer is 15 or less or exceeds 15, as long as the hydrophobic monomer is polymerized in a preferable ratio, the hydrophobicity of the polymer is sufficient. will be maintained at Moreover, from the viewpoint of adjusting the viscosity, a monomer having two or more ethylenically unsaturated groups may be contained regardless of the value of the solubility parameter. Examples of monomers having two or more ethylenically unsaturated groups include ethylene glycol, propylene glycol, polyoxyethylene glycol, polyoxypropylene glycol, glycerin, polyglycerin, trimethylolpropane, pentaerythritol, saccharose, sorbitol, 1, Esters of disubstituted or more hydroxyl groups of polyols such as 4-butanediol and (meth)acrylic acid; disubstituted or more methacrylic acid esters of the above polyols; disubstituted or more hydroxyl groups of the above polyols and allyl alcohol, vinyl alcohol Ethers with unsaturated alcohols such as; mentioned. These other monomers may be used alone or in combination of two or more. From the viewpoint of improving antibacterial properties, the polymer of the present invention may be copolymerized with a polymerizable metal salt as another monomer. Polymerizable metal salts include heavy metal salts of unsaturated carboxylic acids such as zinc acrylate, zinc methacrylate and zinc α-allyloxyacrylate.
of this disclosure

<Molecular weight>
The cationic group-containing polymer contained in the antibacterial agent of the present invention preferably has a weight average molecular weight of 4,000 to 1,000,000. If the weight average molecular weight of the cationic group-containing polymer is in such a range, the adsorption of the antibacterial agent to the material using the antibacterial agent tends to improve, so it is suppressed to be washed away when washed, There is a tendency for the antibacterial effect on the above materials to improve. The weight average molecular weight is preferably 4000 to 800,000, more preferably 5000 to 600,000, still more preferably 6000 to 400,000, still more preferably 7000 to 200,000, still more preferably 7000 to 100,000, particularly preferably 7,000 to 80,000. The weight average molecular weight of the cationic group-containing polymer can be measured by the method described in Examples.

<Polymer composition>
The polymer of the present disclosure has a structural unit derived from a cationic group-containing monomer at a ratio of 36 to 99.9% by mass with respect to 100% by mass of the total amount of structural units forming the polymer. Preferably 40 to 99% by mass, more preferably 42 to 98% by mass, still more preferably 43 to 97% by mass, still more preferably 45 to 96% by mass, particularly preferably 47 to 95% by mass. Yes, most preferably 50 to 94% by mass.
In the polymer of the present disclosure, the content of the primary to tertiary amine per 100 parts by mass of the structural unit derived from the cationic group-containing monomer is 80 parts by mass or more from the viewpoint of low skin irritation. It is preferably 90 parts by mass or more, more preferably 95 parts by mass or more, and may be 100 parts by mass.

The polymer of the present disclosure preferably has a structural unit derived from a hydrophobic monomer at a ratio of 0.01 to 64% by mass with respect to 100% by mass of the total amount of structural units forming the polymer. More preferably 0.05 to 60% by mass, still more preferably 0.1 to 58% by mass, still more preferably 0.5 to 56% by mass, even more preferably 1 to 54% by mass, especially It is preferably 3 to 52% by weight, most preferably 5 to 50% by weight.
In the polymer of the present disclosure, the content ratio of the structural unit derived from the hydrophobic monomer in the polymer is 1 to 100% by mass with respect to 100% by mass of the structural unit derived from the cationic group-containing monomer in the polymer. is preferably More preferably 2 to 95% by mass, still more preferably 3 to 90% by mass, still more preferably 4 to 85% by mass, even more preferably 5 to 80% by mass, particularly preferably 10 to 75% by mass %. When the content ratio of the structural unit derived from the hydrophobic monomer in the polymer of the present invention is within such a range, the antibacterial performance of the polymer tends to be improved.

When the polymer of the present disclosure has a structural unit derived from a (meth)acrylic acid alkyl ester as a structural unit derived from a hydrophobic monomer, the proportion of the structural unit derived from the (meth)acrylic acid alkyl ester forms the polymer It is preferably 0.01 to 64% by mass with respect to 100% by mass of the total amount of structural units. More preferably 1 to 54% by mass, still more preferably 3 to 52% by mass.
In the polymer of the present disclosure, the content of the unsaturated monocarboxylic acid-derived structural unit with respect to the total amount of 100% by mass of the structural units forming the polymer has storage stability such as promotion of hydrolysis of the polymer. From the point of view, it is preferably 0 to 10% by mass. It is more preferably 0 to 8% by mass, still more preferably 0 to 5% by mass.

In the polymer of the present disclosure, the content of structural units derived from unsaturated monocarboxylic acids relative to the total amount of structural units derived from hydrophobic monomers is 100% by mass, from the viewpoint of promoting hydrolysis of the polymer. It is preferably 0 to 10% by mass. It is more preferably 0 to 8% by mass, still more preferably 0 to 5% by mass.
In the polymer of the present disclosure, the content of structural units derived from other monomers is preferably 0 to 10% by mass with respect to 100% by mass of the total amount of structural units forming the polymer. It is more preferably 0 to 8% by mass, still more preferably 0 to 5% by mass. Among other monomers, the content of structural units derived from monomers having two or more ethylenically unsaturated groups is 0 to 1% with respect to 100% by mass of the total amount of structural units forming the polymer. is preferred, more preferably 0 to 0.5% by mass, and still more preferably 0 to 0.1% by mass.

<Acid>
In the present disclosure, the acid is not particularly limited, but is used, for example, for the purpose of neutralizing primary to tertiary amino groups among structural units derived from cationic group-containing monomers. In the composition of the present disclosure, the acid may exist in the form of a salt after being neutralized with the above-mentioned amino group or other base, or may exist in the form of an unneutralized one. Acids used for neutralization include, but are not limited to, inorganic acids and organic acids.
Examples of inorganic acids include phosphoric acid, sulfuric acid, nitric acid, and hydrochloric acid. Phosphoric acid is preferred from the viewpoint of storage stability after neutralization and compatibility with cosmetics.
Examples of organic acids include carboxy group-containing compounds, phosphoric acid group-containing compounds, hydroxycarboxylic acid group-containing compounds, alkyl sulfuric acids, alkyl phosphoric acids, amino acid derivatives, ascorbic acid, taurine, and the like.

Examples of the carboxy group-containing compound of the present disclosure include compounds having one carboxy group such as acetic acid, propionic acid, benzoic acid, aliphatic monocarboxylic acids; malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, Multiple carboxy group-containing compounds such as fumaric acid, phthalic acid, oxalic acid, and diethylenetriaminepentaacetic acid are included, and multiple carboxy group-containing compounds are more preferred. The plurality of carboxy group-containing compounds may have two or more carboxy groups, but preferably have 2 to 10 carboxy groups in one molecule, and have 2 to 5 carboxy groups. is preferred, and preferably has 2 to 3 carboxy groups. When the number of carboxyl groups contained in one molecule is within the above range, the storage stability of the composition of the present disclosure tends to be improved.

Phosphate group-containing compounds of the present disclosure include etidronic acid, phytic acid, and the like.
Hydroxycarboxylic acids of the present disclosure include, for example, glycolic acid, lactic acid, hydroxyacrylic acid, oxybutyric acid, glyceric acid, malic acid, tartaric acid, citric acid, mandelic acid, salicylic acid, gluconic acid, gallic acid, and citric acid. More preferred are acids, lactic acid, malic acid, tartaric acid and mandelic acid.
Amino acid derivatives of the present disclosure include glycine, alanine, valine, leucine, isoleucine, threonine, serine, cysteine, methionine, aspartic acid, asparagine, glutamic acid, diiodotyrosine, lysine, arginine, histidine, phenylalanine, tyrosine, tryptophan, proline. , oxyproline, glutamine, etc., and glutamic acid and aspartic acid are more preferable.

As the acid of the present disclosure, from the viewpoint of water solubility and storage stability, phosphoric acid, multiple carboxyl group-containing compounds, multiple phosphoric acid group-containing compounds, hydroxycarboxylic acid group-containing compounds, amino acid derivatives, and ascorbic acid are preferred, and citric acid, lactic acid, succinic acid, malic acid, tartaric acid, glutamic acid and aspartic acid are more preferred. When the composition of the present disclosure contains an acid selected from the above, the storage stability of the composition tends to be improved.
On the other hand, from the viewpoint of odor, the content of acetic acid is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and further preferably does not contain acetic acid with respect to 100 parts by mass of the acid of the present disclosure. Not included in the present disclosure means intentionally not used.

<Composition>
The composition of the present disclosure is characterized by comprising a polymer (A) having a structural unit derived from a cationic group-containing monomer and a structural unit derived from a hydrophobic monomer, and an acid.
In the composition of the present disclosure, the content of the polymer (A) in 100 parts by mass of the composition may be 0.00001 parts by mass or more from the viewpoint of achieving both the feeling of use and the expression of antibacterial properties, and 0.00005 parts by mass. part or more is preferable, 0.00007 part by mass or more is more preferable, 0.0001 part by mass or more is even more preferable, and from the viewpoint of feeling in use, it may be 5.0 parts by mass or less, preferably 4.0 parts by mass or less, 3.0 parts by mass or less is more preferable, and 2.0 parts by mass or less is even more preferable.
In the composition of the present disclosure, the acid content in 100 parts by mass of the composition may be 0.00001 parts by mass or more, preferably 0.00005 parts by mass or more, and 0.00001 part by mass or more, from the viewpoint of compatibility and storage stability. 0001 parts by mass or more is more preferable, and 0.0005 parts by mass or more is more preferable. It is more preferably 0.5 parts by mass or less, more preferably 0.5 parts by mass or less.
In the composition of the present disclosure, the content of acetic acid in 100 parts by mass of the composition may be 0.1 parts by mass or less, preferably 0.05 parts by mass or less, and 0.02 parts by mass or less from the viewpoint of odor. More preferably, it does not contain acetic acid. Not included in the present disclosure means intentionally not used.

In the composition of the present disclosure, the total amount of acid relative to 1 mol of cationic groups contained in the polymer (A) may be 0.10 mol% or more, preferably 0.15 mol% or more, and 0.20 mol. % or more, more preferably 0.25 mol% or more, may be 1.50 mol% or less, preferably 1.40 mol% or less, more preferably 1.30 mol% or less, 1.20 mol % or less is more preferable. Within the above range, the storage stability of the composition tends to be improved.

In the composition of the present disclosure, the total amount of acid relative to 1 mol of the structural unit derived from the cationic group-containing monomer may be 0.10 mol% or more, preferably 0.15 mol% or more, and 0.20 mol. % or more, more preferably 0.25 mol% or more, may be 1.50 mol% or less, preferably 1.40 mol% or less, more preferably 1.30 mol% or less, 1.20 mol % or less is more preferable.

The composition of the present disclosure can determine the pH of the composition depending on the intended use.
For example, skin care applications; lotion, serum, gel, milky lotion, cream, mist cosmetics, etc. Hair care applications; shampoo, hair rinse, hair conditioner, hair treatment, hair milk, hair mist, hair growth lotion, hair wax, hair gel, hair spray, etc. , make-up applications; liquid foundation, blush, etc., the pH is preferably 2.5 or higher, more preferably 3.0 or higher, even more preferably 3.5 or higher, preferably 8.0 or lower, and more preferably 7.5 or lower. Preferably, 7.0 or less is more preferable. In fatty acid-based body soaps, fatty acid-based facial cleansing foams, solid soaps, etc., the pH is preferably 7.5 or higher, more preferably 8.0 or higher, further preferably 8.5 or higher, further preferably 12.0 or lower, and 11.5. The following is more preferable, and 11.0 or less is even more preferable.
For sun care applications; O/W gel, milk, etc., the pH is preferably 4.5 or higher, more preferably 5.0 or higher, even more preferably 5.5 or higher, more preferably 9.0 or lower, and more preferably 8.5 or lower. 0.0 or less is more preferable.

The composition of the present disclosure may contain compounds other than polymer (A) and acid. Compounds other than the polymer (A) and acid are not particularly limited, but examples include water, nonionic surfactants, alcohols, thickeners, powder components, pH adjusters, anionic surfactants, cationic These include surfactants, amphoteric surfactants, oils, moisturizers, water-soluble polymers, antioxidants, UV absorbers, chelating agents, preservatives, antibacterial agents, coloring agents, fragrances, and the like. etc. For example, a biodegradable chelating agent, 3-hydroxy-2,2' iminodisuccinic acid or a salt thereof (e.g., tetrasodium salt), has antibacterial, scum-inhibiting, and oil-oxidizing-inhibiting effects in the acidic to alkaline range. Since it has an effect of suppressing yellowing, it may be contained in the cosmetic composition of the present disclosure.

In the present disclosure, water includes purified water, distilled water, ion-exchanged water, pure water, soft water, hard water, natural water, deep sea water, alkaline ionized water, and other purified water obtained by various methods.
The composition of the present disclosure preferably contains 1% by mass or more of water, more preferably 5% by mass or more, and 10% by mass or more of water with respect to the total 100% by mass of the cosmetic composition. is more preferred. On the other hand, the cosmetic composition of the present disclosure preferably contains 99% by mass or less of water, more preferably 95% by mass or less, based on the total 100% by mass of the cosmetic composition, and 90% by mass. It is more preferred to include the following: Within the above range, the feeling of use and storage stability when used as a cosmetic tend to be further improved.

In the present disclosure, nonionic surfactants are compounds that do not exhibit ionicity when dissolved in water, but have surface-active properties.
Nonionic surfactants of the present disclosure include ester-type nonionic surfactants, ether-type nonionic surfactants, and the like.
For example, ester-type nonionic surfactants are fatty acid-alcohol esters and fatty acid-sugar esters. For example, glycerin fatty acid ester, sorbitan fatty acid ester, sucrose fatty acid ester, polyglycerin fatty acid ester and the like. The fatty acid is a carboxylic acid having a hydrocarbon group, and the hydrocarbon group preferably has 2 to 25 carbon atoms, more preferably 8 to 22 carbon atoms, and particularly preferably 8 to 18 carbon atoms. For example, ether-type nonionic surfactants include alkylpolyalkylene glycols, which are compounds obtained by adding alkylene oxides to long-chain alcohols, such as alkylpolyethylene glycols and polyoxyethylene alkylphenyl ethers.

In the nonionic surfactant of the present disclosure, as one preferred form, two or more types of nonionic surfactants having different HLB (Hydrophilic-Lipophilic Balance) values can be used. As a value indicating the degree of affinity of a surfactant for water and oil, there is an HLB (Hydrophilic-Lipophilic Balance) value. It can be suitably used as an emulsifier, and if the HLB value is 3 to 6, it has low solubility in water, but can be slightly dispersed, and can be suitably used as a W/O type emulsifier.

When using two or more types with different HLB values, at least one type selected from nonionic surfactants with an HLB value of 8 to 16 and one type selected from nonionic surfactants with an HLB value of 3 to 6 Use the above. By using two types of nonionic surfactants with different HLB values, the bilayer structure that constitutes α-gel is fixed, and the strength of the formed oil droplets increases and stabilizes as a strong bilayer. becomes. For example, nonionic surfactants having an HLB value of 8 to 16 are polyglycerin fatty acid esters, and particularly preferably polyglyceryl 5 stearate. For example, nonionic surfactants having an HLB value of 3 to 6 are glycerin fatty acid esters, particularly preferably glyceryl stearate.

When using one or more selected from nonionic surfactants with an HLB value of 8 to 16 and one or more selected from nonionic surfactants with an HLB value of 3 to 6, the total mass of the nonionic surfactant %, the ratio of one or more selected from nonionic surfactants having an HLB value of 8 to 16 is preferably 30% to 90% by mass. Within this range, the crystal structure of α-gel is stable. When two or more different HLB types are mixed as described above, a higher alcohol may be used as necessary. A higher alcohol is an alcohol having a hydrocarbon group with 8 or more carbon atoms, and the hydrocarbon group may be linear or branched. It is particularly preferable to use a combination of one or more of 14 to 22 carbon atoms.
When using a nonionic surfactant with an HLB of 8 to 16 as another preferred form of the nonionic surfactant of the present disclosure, one type selected from nonionic surfactants with an HLB value of 3 to 6 When not using the above, it is preferable to use a higher alcohol. By using a nonionic surfactant and a higher alcohol with such a high HLB value, the bilayer structure that constitutes the α-gel is fixed, and the strength of the oil droplets that form a strong bilayer is increased and stabilized. becomes. A higher alcohol is an alcohol having a hydrocarbon group with 8 or more carbon atoms, and the hydrocarbon group may be linear or branched. It is particularly preferable to use a combination of one or more of 14 to 22 carbon atoms.
Oil agents of the present disclosure include, for example, hydrocarbons such as liquid paraffin and squalane, waxes such as jojoba oil and liquid lanolin, isopropyl myristate, glyceryl tri-2-ethylhexanoate, diglyceryl diisostearate, and tri-2-ethylhexane. Esters such as acid trimethylolpropane, oils such as castor oil and macadamia nut oil, chain polysiloxanes such as dimethylpolysiloxane and methylphenylpolysiloxane, cyclic polysiloxanes such as octamethylcyclotetrasiloxane and decamethylcyclopentasiloxane, Examples thereof include silicone oils such as amino-modified silicone.
Moisturizers of the present disclosure include polyhydric alcohols and sugars, and specific examples include propylene glycol, 1,3-butylene glycol, 1,3-propanediol, dipropylene glycol, and 1,2-pentanediol. , 1,2-hexanediol, isoprene glycol, diglycerin, methylpropanediol, glycerin, xylitol, sorbitol, maltitol, mannitol, erythritol, and the like.
When the composition of the present disclosure contains a polyhydric alcohol, the polyhydric alcohol used as the solvent for polymerizing the polymer (A) may be used as it is.
The moisturizing agent used in the present disclosure may contain two or more moisturizing agents. For example, propylene glycol, 1,3-butylene glycol, 1,3-propanediol, dipropylene glycol, 1,2-pentanediol, 1,2-hexanediol, isoprene glycol, diglycerin, divalent divalent diol such as methylpropanediol A mixture obtained by mixing an alcohol compound with a trihydric or higher alcohol compound such as glycerin, xylitol, sorbitol, maltitol, mannitol, erythritol, etc. may be used, and propylene glycol, 1,3-butylene glycol, 1,3-propanediol, dipropylene glycol, 1,2-pentanediol and 1,2-hexanediol are more preferred, and propylene glycol, 1,3-butylene glycol, 1,3-propanediol and dipropylene glycol are further preferred. 1,3-butylene glycol is particularly preferred, and glycerin is more preferred as the trihydric or higher alcohol compound. By using a mixture in which two or more kinds of moisturizing agents are mixed, an effect of improving feeling of use and moisturizing property can be expected. The mixture may be added separately when preparing the cosmetic, but it is also preferable to mix in advance.
Examples of the mixture of two or more moisturizing agents include a combination of a dihydric alcohol compound and a trihydric or higher alcohol compound. The mass of alcohol compound/mass of trihydric or higher alcohol compound) may be 90.0/10.0 to 99.9/0.1, 95/5 to 99.7/0.3, 99 .0/1.0 to 99.5/0.5, 99.0/1.0 to 99.4/0.6, 99.1/0.9 to 99.3/0.7 . By containing the alcohol compound having a valence of 3 or more in the above range, the effect of improving the feeling of use and moisturizing property can be expected.
A mixture in which two or more moisturizers are mixed includes a combination of 1,3-butylene glycol and glycerin, and the mass ratio of 1,3-butylene glycol and glycerin (mass of 1,3-butylene glycol/glycerin mass) may be 90.0/10.0 to 99.9/0.1, 95/5 to 99.7/0.3, 99.0/1.0 to 99.5/0 .5, 99.0/1.0 to 99.4/0.6, 99.1/0.9 to 99.3/0.7. By including glycerin in the above range, the effect of improving the feeling of use and moisturizing can be expected.
Colorants of the present disclosure include, for example, inorganic pigments, natural pigments, and the like.
Cooling agents of the present disclosure include menthol, menthoxypropanediol, monomenthyl glyceryl ether, menthyl lactate, camphor, eugenol, mint oil, peppermint oil, and the like.

<Method for producing polymer (A)>
Although the production of the polymer (A) of the present invention is not particularly limited, it can be produced by including a step of polymerizing a monomer component (hereinafter also referred to as a “polymerization step”). Examples and preferred examples are given above.
The above polymer (A) is preferably produced by a method of polymerizing the above monomer components in the presence of a polymerization initiator. That is, the polymerization step is preferably carried out in the presence of a polymerization initiator. When polymerizing the monomer component, a polymerization initiator can be appropriately used depending on the polymerization method.

As the polymerization initiator, those commonly used can be used, for example, hydrogen peroxide; persulfates such as sodium persulfate and ammonium persulfate; dimethyl 2,2'-azobis(2-methylpropionate ), 2,2′-azobis(isobutyronitrile), 2,2′-azobis(2-methylbutyronitrile), 2,2′-azobis(isobutyrate)dimethyl, 4,4′-azobis(4 -cyanovaleric acid), 2,2′-azobis(2-methylpropionamidine) dihydrochloride, 2,2′-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] n-hydrate, 2,2'-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride, 2,2'-azobis[2-(2-imidazolin-2-yl)propane]disulfate dihydrate product, 1,1′-azobis(cyclohexane-1-carbonitrile), 2,2′-azobis[N-(2-propenyl)-2-methylpropionamide], 2,2′-azobis(2,4- azo compounds such as dimethylvaleronitrile); organic peroxides such as benzoyl peroxide, lauroyl peroxide, peracetic acid, and di-t-butyl peroxide; Among these polymerization initiators, azo compounds are preferred. The polymerization initiator is not limited to those exemplified above. These polymerization initiators may be used alone or in combination of two or more.
The amount of the polymerization initiator to be used is not particularly limited as long as it is an amount capable of initiating the polymerization of the monomer components. , preferably 0.05 to 30 parts by mass, more preferably 0.05 to 20 parts by mass.

As a method of using the cationic group-containing monomer of the present disclosure, it may be used as a quaternary ammonium salt quaternized with a quaternizing agent. The quaternizing agent for the cationic group-containing monomer is as described above. The amount of the quaternizing agent to be used is preferably 0.1 to 1 mol per 1 mol of the cationic group-containing monomer.
As for the method of quaternization of the cationic group-containing monomer, a method of post-addition by adding a quaternizing agent after polymerizing the polymer of the present invention is also preferred. The amount of the quaternizing agent to be used is preferably 0.1 to 1 mol per 1 mol of the cationic group-containing monomer.

In the above polymerization method or polymerization process, as a method of adding the monomer components, the polymerization initiator, etc. to the reaction vessel, all the monomer components are charged into the reaction vessel, and the polymerization initiator is added into the reaction vessel. A method of carrying out copolymerization by charging a part of the monomer components into the reaction vessel, and continuously or stepwise (preferably continuously) adding the polymerization initiator and the remaining monomer components into the reaction vessel. A method of performing copolymerization by charging a polymerization solvent into a reaction vessel and adding the total amount of a monomer component and a polymerization initiator; One of the monomers (e.g., a cationic group-containing monomer) is charged into a reaction vessel, and the polymerization initiator and the rest of the monomer components are added (preferably continuously) into the reaction vessel for copolymerization. Among these methods, it is possible to narrow (sharpen) the molecular weight distribution of the resulting polymer, so copolymerization is carried out by a method in which a polymerization initiator and a monomer component are successively added dropwise to a reaction vessel. is preferred.

Examples of the copolymerization method include solution polymerization, bulk polymerization, suspension polymerization, emulsion polymerization, living polymerization, graft polymerization, and the like, and are not particularly limited, but solution polymerization is preferred. The solvent that can be used at this time is preferably water alone or a mixed solvent of water and a solvent. When only water is used, it is preferable in that the solvent removal step can be omitted. The above polymerization method or polymerization process can be carried out either batchwise or continuously. In addition, as the solvent used as necessary in the copolymerization, a known solvent can be used, and water; methyl alcohol, ethyl alcohol, isopropyl alcohol, butanol, monohydric alcohols such as THF (tetrahydrofuran); polyhydric alcohols such as glycerin, (poly)ethylene glycol, propylene glycol, 1,3-butylene glycol (1,3-butanediol) and dipropylene glycol; aromatics such as benzene, toluene, xylene, cyclohexane and n-heptane or aliphatic hydrocarbons; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; amides such as dimethylformamide; ethers such as diethyl ether and dioxane. These may be used alone or in combination of two or more. Among these, it is preferable to use one or more solvents selected from the group consisting of water and lower alcohols having 1 to 4 carbon atoms, from the viewpoint of the solubility of the monomer component and the resulting polymer. . The solvent is relatively inexpensive, and the production method of the present invention is economically superior. In the above copolymerization method, a polyhydric alcohol solvent such as propylene glycol or ethylene glycol may be added to water for polymerization. By using the polyhydric alcohol solvent in combination with water, the solubility of the polymer can be enhanced, and the soap-free polymerization can be more sufficiently suppressed. This makes it possible to more sufficiently suppress the formation of polymers with poor water solubility and further improve the transparency of the solution. When the polyhydric alcohol solvent and water are used together, the ratio of the polyhydric alcohol solvent to 100% by weight of water is preferably 0 to 200% by weight. Any chain transfer agent, pH adjuster, buffering agent, and the like can be used in the method for producing the polymer of the present invention, if necessary. The resulting polymer may be arbitrarily soluble or arbitrarily dispersible in water, but arbitrarily water-soluble polymers are particularly preferred. The temperature during the polymerization is not particularly limited, but is usually 50 to 120°C, preferably 60 to 110°C. When the temperature during polymerization is within the above range, the residual monomer component tends to decrease. The temperature at the time of polymerization does not need to be kept constant during the polymerization reaction. Thereafter, the set temperature may be maintained, or the polymerization temperature may be varied (increased or decreased) over time during the progress of the polymerization reaction, depending on the dropping method of the monomer component, initiator, etc. good too.

Moreover, when polymerizing the monomer component, it is preferable to stir the mixture as appropriate in order to uniformly polymerize the monomer component.
The polymerization time in the above polymerization is not particularly limited, and may be appropriately set according to the progress of the polymerization reaction, but is usually about 2 to 9 hours. In the present invention, "polymerization time" means the time during which the mixture is heated and stirred before dropping the monomer, the time during which the monomer is added, and the aging time after dropping the monomer.
The pressure in the reaction system in the above polymerization may be normal pressure (atmospheric pressure), reduced pressure, increased pressure, or a combination thereof. The atmosphere in the reaction system may be either an air atmosphere or an inert atmosphere.

The solid content concentration in the aqueous solution (that is, the polymerization solid content concentration of the monomer) at the time when the polymerization reaction in the polymerization reaction system is completed is preferably 20% by mass or more, more preferably 25 to 80% by mass. . If the solid content concentration at the end of the polymerization reaction is as high as 20% by mass or more, polymerization can be carried out at a high concentration in one step. Therefore, the antibacterial agent containing the polymer can be efficiently obtained, such as by omitting the concentration step that was necessary in some cases in the conventional production method. Therefore, the production efficiency can be greatly increased, and as a result, the productivity of the antibacterial agent of the present invention can be greatly improved, and the increase in production cost can be suppressed.

In the method for producing the polymer of the present invention, an aging step may be provided for the purpose of increasing the polymerization rate of the monomer after the addition of all the raw materials used. Aging time is usually 1 to 240 minutes, preferably 1 to 180 minutes, more preferably 1 to 120 minutes. If the aging time is less than 1 minute, the monomer component may remain due to insufficient aging, causing problems such as toxicity and odor caused by the residual monomer.
Moreover, the preferred temperature of the polymer solution in the aging step is in the same range as the above polymerization temperature. Therefore, the temperature here may be maintained at a constant temperature (preferably the temperature at the time when the dropping is completed), or the temperature may be changed over time during aging.
The method for producing the polymer of the present disclosure may include any other steps as necessary in addition to the polymerization steps described above. Examples of the optional steps include an aging step, a concentration step, a purification step, a drying step, a dilution step, and the like.

<Method for producing composition>
The composition of the present disclosure includes a step of adding an acid to the polymer (A) obtained by the production method described above. Specific examples and preferred examples of the acid are as described above.
In the method for producing the composition of the present disclosure, the total amount of acid relative to 1 mol of the cationic group monomer of the polymer (A) is from the viewpoint of solubility in water and storage stability when dissolved in water. It may be 1.50 mol % or less, preferably 1.40 mol % or less, more preferably 1.30 mol % or less, and even more preferably 1.20 mol % or less.
The compositions of the present disclosure may contain other additives as described above.

<Application>
The composition of the present disclosure is preferably used for cosmetics such as skin cosmetics, external skin preparations, and hair (hair) cosmetics.
The above-mentioned skin cosmetics are not particularly limited, but for example, skin care cosmetics such as lotions, creams, gels, milky lotions, and serums; Cleansing cosmetics such as cleansing creams, facial cleansing foams, and liquid facial cleansers; Cosmetics such as sunscreen cosmetics (including quasi-drugs); Bath cosmetics such as bath agents. Examples of skin preparations for external use include external medicines such as liniments, lotions, and ointments.
The hair cosmetics are not particularly limited, and examples include shampoos, rinses, treatments, waxes, sprays, gels, mists, and the like.

EXAMPLES The present invention will be described in more detail with reference to examples below, but the present invention is not limited only to these examples. Unless otherwise specified, "part" means "mass part" and "%" means "mass %".
<Weight average molecular weight (Mw) measurement>
Apparatus: EcoSEC HLC-8320GPC manufactured by Tosoh Corporation
Detector: Differential refractometer (RI) detector Column: TSKgel α-M, α-2500 manufactured by Tosoh Corporation
Column temperature: 40°C
Flow rate: 0.4 mL/min
Injection volume: 20 µL (eluent preparation solution with a sample concentration of 0.4 wt%)
Calibration curve: Polyethylene glycol manufactured by GL Sciences Inc. Eluent: 0.5 M acetic acid + 0.2 M Na nitrate/acetonitrile = 50/50 (v/v)

<Compatibility>
<Viscosity measurement> Using a B-type viscometer (model: BMII) (manufactured by Toki Sangyo Co., Ltd.), the rotor No. was measured. 4. Measured under the conditions of rotation speed of 12 rpm, measurement time of 60 seconds, and temperature of 25°C.
<pH measurement>
Measured with a pH meter LAQUA pH/ION METER F-72 manufactured by HORIBA. Measurement temperature was measured at 25°C.
<Storage Stability> The product was stored in an incubator at room temperature, 5° C., and 50° C. for one month, and evaluated by five expert panelists.
<Feeling of use> A sensory evaluation was conducted by five expert panelists.
<Method for evaluating storage stability and feeling in use> Absolute evaluation of storage stability and feeling in use was performed by five expert panelists according to the following evaluation criteria. Judged. The criteria for judgment were shared storage stability and feeling during use.
<Evaluation criteria> Storage stability / feeling of use 3 points: No separation / creaming / No stickiness and watery 1 point: Slight separation / creaming / Slight stickiness 0 points: Separation / creaming Occurs / sticky <judgment criteria>
○: 2.5 points or more △: 1.0 points or more and less than 2.5 points ×: less than 1.0 points

<MIC (minimum inhibitory concentration)>
An aqueous solution containing the copolymer was serially diluted in Mueller-Hinton medium by 2-fold to prepare serial dilutions of the copolymer-containing medium. After that, 50 μL each of the medium containing each concentration of the copolymer was added to a polystyrene 96-well plate. Next, a colony of Escherichia coli (NBRC-3972) or Staphylococcus aureus (NBRC-13276) or Pseudomonas aeruginosa (NBRC-13275) grown on Mueller Hinton agar medium for 18 hours was The cells were suspended in Butterfield's buffer to prepare a bacterial solution containing about 10×10 8 cells/mL. The prepared bacterial solution was diluted to about 10×10 6 cells/mL in Mueller-Hinton medium, and 50 μL was added to each dilution series prepared above. After standing at 35° C. for 20 hours, the minimum antibacterial agent concentration (ppm) in the medium in which no bacteria were growing was determined as the minimum inhibitory concentration (MIC). The presence or absence of growth of bacteria was judged by visual observation whether turbidity increased. The MIC value is preferably 300 ppm or less, more preferably 200 ppm or less, even more preferably 100 ppm or less, and particularly preferably 80 ppm or less. An MIC value of 300 ppm or less is preferable because the amount of the antibacterial agent to be added to exhibit bacteriostatic performance is not too large.
<Preservation efficacy test>
A preservative efficacy test of the composition of the present disclosure was performed according to the method described in the Japanese Pharmacopoeia. Escherichia coli and Staphylococcus aureus were used as target bacteria. Bacterial viability was measured 4 hours, 3 days and 7 days after inoculation.
The antibacterial property is judged to be 0 (antibacterial) if the bacterial survival rate after 4 hours is 1% or less of the number of inoculated bacteria and the number of bacteria continues to decrease after 3 and 7 days. The others were rated as x (no antibacterial properties).

[Synthesis Example - Synthesis of Polymer Containing Cationic Group]
<Synthesis Example 1>
A separable glass flask equipped with a thermometer, a reflux condenser, and a stirrer was charged with 29.4 g of pure water and 100.0 g of 1,3-butanediol (manufactured by KH Neochem), and the temperature was raised to 90°C while stirring. I warmed up. Then, 60.0 g of 2-(dimethylamino)ethyl methacrylate (N,N-dimethylaminoethyl methacrylate) (manufactured by Kyoeisha Chemical Co., Ltd., hereinafter referred to as DAM) is placed in a polymerization reaction system maintained at a constant temperature of 80° C. while stirring. Monomer solution 1, monomer solution 2 consisting of 40.0 g of ethyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., hereinafter referred to as EMA), 2,2'-azobis (2-methylpropionamidine) dihydrochloride (Fujifilm Wako Pure An aqueous initiator solution consisting of 18.3 g of a 10% aqueous solution (manufactured by Yakusha, hereinafter referred to as V-50) was dropped from separate dropping nozzles. Dropping of the monomer solutions 1 and 2 and the aqueous initiator solution was started at the same time, and the monomer solution 1 was dropped for 180 minutes, the monomer solution 2 for 170 minutes, and the aqueous initiator solution for 210 minutes. After the completion of all dropping, the reaction solution was kept at 80° C. for an additional 30 minutes for aging to complete the polymerization. got The obtained copolymer 1 had a solid content of 19.7%, a pH of 9.0 and a weight average molecular weight of 30,000.

[Production Example - Preparation of Aqueous Solution Containing Copolymer]
<Production Example 1>
Citric acid was added to the copolymer 1 to adjust the pH to 6 to prepare an aqueous solution having a solid concentration of 2%.
<Production Example 2>
Preparations were made in the same manner as in Production Example 1, except that citric acid in Production Example 1 was changed to lactic acid.
<Production Example 3>
Preparations were made in the same manner as in Production Example 1 except that citric acid in Production Example 1 was changed to phosphoric acid.
<Production Example 4>
It was prepared in the same manner as in Production Example 1 except that citric acid in Production Example 1 was changed to succinic acid.
<Production Example 5>
It was prepared in the same manner as in Production Example 1 except that citric acid in Production Example 1 was changed to malic acid.
<Production Example 6>
Preparations were made in the same manner as in Production Example 1 except that citric acid in Production Example 1 was changed to etidronic acid.
<Production Example 7>
It was prepared in the same manner as in Production Example 1 except that citric acid in Production Example 1 was changed to ascorbic acid.
<Production Example 8>
It was prepared in the same manner as in Production Example 1 except that citric acid in Production Example 1 was changed to mandelic acid.
<Production Example 9>
Preparations were made in the same manner as in Production Example 1, except that citric acid in Production Example 1 was changed to glutamic acid.
<Production Example 10>
It was prepared in the same manner as in Production Example 1 except that citric acid in Production Example 1 was changed to aspartic acid.
<Production Example 11>
It was prepared in the same manner as in Production Example 1 except that citric acid in Production Example 1 was changed to tartaric acid.
<Comparative Production Example 1>
Ion-exchanged water was added to adjust the solid content concentration of the copolymer 1 to 2%.
<Comparative Production Example 2>
It was prepared in the same manner as in Production Example 1 except that the citric acid in Production Example 1 was changed to phytic acid.
<Comparative Production Example 3>
It was prepared in the same manner as in Production Example 1 except that citric acid in Production Example 1 was changed to serine.
<Comparative Production Example 4>
It was prepared in the same manner as in Production Example 1, except that taurine was used instead of citric acid in Production Example 1.
Production Examples 1 to 11 and Comparative Production Examples 1 to 4 were evaluated for storage stability, pH, and antimicrobial activity (MIC). The results are shown in Tables 1, 2 and 3.

As shown in Tables 1 and 2, Production Examples 1 to 11 were found to be excellent in storage stability.
As shown in Table 3, Production Examples 1 to 11 were found to be excellent in antibacterial properties.

[Production Example - Production of Copolymer-Containing Composition]
<Production Example 12>
(1) 65.5 parts of ion-exchanged water, 5.0 parts of 1,3-butylene glycol-P (manufactured by KH Neochem Co., Ltd.), and 8.0 parts of concentrated glycerin for cosmetics (manufactured by Sakamoto Pharmaceutical Co., Ltd.) , and 5.0 parts of Sunsoft α-C (manufactured by Taiyo Kagaku Co., Ltd.), heated to 80° C.±5° C. with stirring, and dissolved until uniform. (2) Olive squalane (manufactured by KOKYU ALCOHOL KOGYO Co., Ltd.) 5.0 parts, CEH (manufactured by KOKYU ALCOHOL KOGYO Co., Ltd.) 5.0 parts, and KF-96A-100CS (manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 part and 1.0 part of TAISET 50-C (manufactured by Taiyo Kagaku Co., Ltd.) are mixed and heated to 80° C.±5° C. with stirring until dissolved uniformly. (3) While heating (1) to 80°C ± 5°C, stir at 5000 rpm with a homomixer (Labolution manufactured by Primix Co., Ltd.), add (2) little by little and emulsify to form a uniform mixture. , and cooled to 35°C. (4) In (3), citric acid was added to copolymer 1 to adjust the pH to 6, and 5.0 parts of an aqueous solution of copolymer 1 adjusted to an aqueous solution with a solid content concentration of 2% was mixed with stirring. Twelve O/W emulsions were obtained.

<Production Example 13>
An O/W emulsion of Production Example 13 was obtained in the same manner as in Production Example 11 except that citric acid added to Copolymer 1 was changed to lactic acid.
<Production Example 14>
An O/W emulsion of Production Example 14 was obtained in the same manner as in Production Example 11 except that the citric acid added to Copolymer 1 was changed to phosphoric acid.
<Production Example 15>
An O/W emulsion of Production Example 15 was obtained in the same manner as in Production Example 11, except that succinic acid was used instead of citric acid added to Copolymer 1.
<Production Example 16>
An O/W emulsion of Production Example 16 was obtained in the same manner as in Production Example 11, except that the citric acid added to Copolymer 1 was changed to malic acid.
<Production Example 17>
An O/W emulsion of Production Example 17 was obtained in the same manner as in Production Example 11, except that etidronic acid was used instead of citric acid added to Copolymer 1.
<Production Example 18>
An O/W emulsion of Production Example 18 was obtained in the same manner as in Production Example 11, except that ascorbic acid was used instead of the citric acid added to Copolymer 1.
<Production Example 19>
An O/W emulsion of Production Example 19 was obtained in the same manner as in Production Example 11, except that the citric acid added to Copolymer 1 was changed to mandelic acid.
<Production Example 20>
An O/W emulsion of Production Example 20 was obtained in the same manner as in Production Example 11, except that glutamic acid was used instead of citric acid added to Copolymer 1.
<Production Example 21>
An O/W emulsion of Production Example 21 was obtained in the same manner as in Production Example 11 except that the citric acid added to Copolymer 1 was changed to aspartic acid.
<Production Example 22>
An O/W emulsion of Production Example 22 was obtained in the same manner as in Production Example 11, except that the citric acid added to Copolymer 1 was changed to tartaric acid.
<Comparative Production Example 5>
An O/W type emulsion of Comparative Production Example 5 was obtained in the same manner as in Production Example 11 except that the aqueous solution of Copolymer 1 adjusted to a solid content concentration of 2% was not added.
Production Examples 12 to 22 and Comparative Production Example 5 were evaluated for pH, viscosity, storage stability, feeling during use, and antibacterial properties (preservation efficacy test). Table 4 shows the results.

As shown in Tables 4 and 5, Production Examples 11 to 20, which use polymers containing cationic groups, have good blendability when used as O/W emulsion formulations, and are also excellent in storage stability. I understood it. As for the feel during use, Production Examples 11 to 20 were as good as Comparative Production Example 5 without stickiness.
Regarding the preservative efficacy test, it was found that Production Examples 11 to 20, in which a polymer containing a cationic group was blended, had antibacterial properties against both Escherichia coli and Staphylococcus aureus. After 3 days and 7 days, no increase in the number of bacteria was observed in the preservation efficacy test, and it was found that the antimicrobial activity was maintained for a long period of time. Since Comparative Production Example 5 does not have antibacterial properties, it was found that the polymer containing a cationic group imparts antibacterial properties to the O/W emulsion, and is excellent in storage stability and feeling during use.

For 1,3-butylene glycol and glycerin, the weight ratio of 1,3-butylene glycol to glycerin was 90:10, 95:5, 99:1, 99.1:0.9, 99.4:0.6. A mixture was prepared.
Using the above mixture of 1,3-butylene glycol and glycerin, Production Examples 23 to 27 were prepared as compositions with a polymer containing a cationic group, as shown in Table 6 below. BG in the table has the same meaning as 1,3-butylene glycol.

As shown in Table 6, a mixture of 1,3-butylene glycol and glycerin was used, and Production Examples 23 to 27 using a polymer containing a cationic group were O/W emulsion formulations. It was found to have good properties and excellent storage stability. As for the feeling during use, it was as good as Production Example 12 and Comparative Production Example 5 without stickiness.

<Raw materials used>
*1 Citric acid monohydrate (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
*2 Musashino Lactic Acid 50F (manufactured by Musashino Chemical Laboratory)
*3 Phosphoric acid (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
*4 Succinic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
*5 DL-malic acid (Fujifilm Wako Pure Chemical Industries)
*6 Cherest 210SD (manufactured by Cherest)
*7 L(+)-ascorbic acid (manufactured by FUJIFILM Wako Pure Chemical Industries, Ltd.)
*8 (±)-mandelic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
*9 L-glutamic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
* 10 L-aspartic acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
*11 L(+)-tartaric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
*12 50% phytic acid solution (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
*13 L-serine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
*14 Taurine (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)
*15 1,3-butylene glycol-P (manufactured by KH Neochem)
*16 Concentrated glycerin for cosmetics (manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.)
*17 Sunsoft α-C (manufactured by Taiyo Kagaku Co., Ltd.)
* 18-CEH (manufactured by Kokyu Alcohol Kogyo Co., Ltd. * 19-Olive squalane (manufactured by Kokyu Alcohol Kogyo Co., Ltd.)
* 20-KF-96A-100CS (manufactured by Shin-Etsu Chemical Co., Ltd.)
* 21-TAISET 50-C (manufactured by Taiyo Kagaku Co., Ltd.)

Claims (6)

A polymer (A) having a structural unit derived from a cationic group-containing monomer and a structural unit derived from a hydrophobic monomer, and an acid, wherein the total amount of acid per 1 mol of the cationic group is 0.10 mol. % or more and 1.50 mol % or less. The proportion of structural units derived from cationic group-containing monomers relative to 100 parts by mass of the polymer is 50% by mass or more and 95% by mass or less, and the proportion of structural units derived from hydrophobic monomers is 5% by mass or more and 50% by mass. % or less. The acid is one or more compounds (B) selected from the group consisting of phosphoric acid, multiple carboxy group-containing compounds, multiple phosphoric acid group-containing compounds, hydroxycarboxylic acid group-containing compounds, amino acid derivatives and ascorbic acid. 3. A composition according to claim 1 or 2. The composition according to any one of claims 1 to 3, which contains a nonionic additive. A cosmetic using the composition according to any one of claims 1 to 4. a step of polymerizing a cationic group-containing monomer and a hydrophobic monomer; and a step of adding an acid to the polymer (A) obtained by the above steps. A method for producing a composition in which the total amount of is 1.50 mol % or less.