KR102146899B1 - Acrylic resin emulsion for hairdressing agents, hairdressing agent comprising same, and hairdressing method - Google Patents

Abstract

It is an object of the present invention to provide a suitable acrylic resin emulsion in order to obtain a hairdressing material having excellent styling performance (hairdressing performance, re-hairing performance, tactile sensibility) and cleaning performance in balance. The acrylic resin emulsion for a hairdressing agent of the present invention contains an acrylic resin (A) dispersed and stabilized with a polyvinyl alcohol resin [I].

Description

Acrylic resin emulsion for hairdressing agent, hairdressing agent comprising same, and hairdressing method {Acrylic resin emulsion for hairdressing agent, hairdressing agent comprising same, and hairdressing method}

The present invention relates to an acrylic resin emulsion useful for a hairdressing agent (hair styling agent).

As a hairdressing agent, there are various formulations such as liquid, gel, foam, spray, cream, and wax. Usually, a hairdressing agent is to form a film on the surface of the hair, and it is mainly composed of a polymer (set polymer) for maintaining a desired shape, and additives given for various purposes, a solvent, a base agent, etc. that are blended according to the formulation. It is a blended polymer composition. Hairdressing agents have recently become mainstream hair creams and hair waxes, which are emulsifiers using oil and water, as a formulation that allows hair to be freely arranged at the time of hairdressing and is easy to correct even after hairdressing.

In addition, a hairdressing agent is required to give the hair a desired shape for a long time to maintain it, or to perform styling such as excellent appearance performance, excellent tactile performance, etc., in addition to cleaning the hairdressing agent from the hair after use. · Ease of removal is also required as a performance, and various hairdressing agents are being developed.

For example, in Patent Document 1, an aqueous solution-type hairdressing agent using a polyvinyl alcohol-based resin having a specific structure as a main component of a polymer component as a main component is described, and in Patent Document 2, beeswax and an interface A hair cosmetic composition in which polyvinyl alcohol is blended as a blending agent is described in an emulsion composition consisting of an activator and water.

(Patent Document 1) JP 2009-286724 A (Patent Document 2) JP 2011-148721 A

The hairdressing agent of Patent Document 1 claims the performance that the polyvinyl alcohol-based resin of a specific structure has good curl retention under high humidity conditions, has little stickiness, and has moisturizing power, so that damage to hair is small, In addition, the hairdressing agent of Patent Document 2 claims the ability to enhance aesthetics in use by blending a polyvinyl alcohol-based resin in an emulsion composition and not to impart unnatural gloss to the hair after application. However, in the hairdressing agent described in Patent Document 1, there is still room for improvement in terms of the good point of good communication with a finger comb (finger), a comb, or a brush, and in terms of re-election once the hairdressing is broken. , In the hairdressing agent described in Patent Document 2, since the stickiness is large and the feeling of use is poor, further improvement is required.

In addition, while the hairdressing agent is required to be easily cleaned after use, in the case of exposure to sweat or rain due to dampness during use, the hairdressing may fall off and stick to the forehead or cheeks and cause inconvenience, such as being unable to rehair. Since it should not be, it is said that it is also necessary to have an adequate performance to be cleaned.

Accordingly, the present invention provides an acrylic resin emulsion that is effectively used as a hairdressing agent excellent in balance between styling performance (hairdressing performance (setting force), resetting performance (resetting force), tactile sensibility) and performance to be cleaned under this background. It is for the purpose of.

However, the inventors of the present invention have conducted extensive research in consideration of such circumstances, and as a result, polyvinyl alcohol-based resins, which have been conventionally used as main polymers or blending agents, can be obtained by using as dispersion stabilizers for acrylic resins. The present invention was completed by discovering that a hairdressing agent containing an emulsion that is excellent in balance in styling performance (hairdressing performance (setting power), rehairing performance (resetting power), tactile sensibility) and performance to be cleaned.

That is, the gist of the present invention relates to the following (1) to (7).

(1) An acrylic resin emulsion for a hairdressing agent containing an acrylic resin (A) dispersed and stabilized with a polyvinyl alcohol resin [I].

(2) The acrylic resin emulsion for a hairdressing agent according to the above (1), wherein the polyvinyl alcohol-based resin [I] contains a side chain 1,2-diol structural unit represented by the following general formula 1.

[General Formula 1]

(In formula (1), R ¹ to R ⁶ each independently represent a hydrogen atom or an organic group, and X represents a single bond or a bonded chain.)

(3) In the above (2), the content rate of the side chain 1,2-diol structural unit in the polyvinyl alcohol resin [I] containing the side chain 1,2-diol structural unit represented by formula (1) is 1 to 15 mol% acrylic resin emulsion for hairdressing.

(4) The monomer component according to any one of (1) to (3) above, wherein the acrylic resin (A) contains 40% by weight or more of an aliphatic (meta) acrylate monomer having 4 to 12 carbon atoms in the alkyl group. Acrylic resin emulsion for a hairdressing agent obtained by polymerization of.

(5) The acrylic resin emulsion for a hairdressing agent according to any one of (1) to (4) above, wherein the glass transition temperature of the acrylic resin (A) is 70°C or less.

(6) Hairdressing agent containing the acrylic resin emulsion for hairdressing agents in any one of said (1)-(5).

(7) A step of applying an acrylic resin emulsion for a hairdressing agent containing an acrylic resin (A) dispersed and stabilized with a polyvinyl alcohol resin [I] to the hair, and applying the acrylic resin emulsion for a hairdressing agent. Or before and after, a hairdressing method including a step of arranging the hair into a desired shape.

Since the acrylic resin emulsion for a hairdressing agent of the present invention is excellent in water solubility and/or redispersibility in water, a hairdressing agent made by using the acrylic resin emulsion for a hairdressing agent is excellent in performance to be cleaned, and is also in balance with styling performance. It has an excellent effect.

Hereinafter, although this invention is demonstrated in detail, these show an example of a preferable embodiment. In addition, in the present invention, (meth)acrylic refers to acrylic or methacrylic, (meth)acryloyl refers to acryloyl or methacrylate, and (meth)acrylate refers to acrylate or methacrylate, respectively. , Acrylic resin is a resin obtained by polymerizing a monomer component containing at least one (meth)acrylic monomer.

The acrylic resin emulsion for a hairdressing agent of the present invention contains an acrylic resin (A) dispersed and stabilized by a polyvinyl alcohol resin (hereinafter referred to as "PVA resin") [I].

In the present invention, the dispersion-stabilized state is a dispersed state in which the emulsion is left to stand at 23°C for 1 month without sedimentation and separation, and maintains a uniform state.

<Polyvinyl alcohol resin [I]>

As the PVA-based resin [I], a PVA-based resin having a specific average degree of saponification and an average degree of polymerization shown below is preferable.

The average saponification degree of the PVA-based resin [I] is preferably 70 to 99.9 mol%, particularly preferably 80 to 99.5 mol%, and still more preferably 85 to 99.9 mol%. If such an average degree of saponification is too low, the polymerization is difficult to proceed stably, and even when polymerization is completed, the storage stability of the emulsion tends to decrease, and too high emulsification stability decreases, resulting in a tendency to become difficult to manufacture.

In addition, in the present invention, the average degree of saponification can be calculated according to the method of calculating the degree of saponification described in JIS K 6726 (1994).

Moreover, as the average degree of polymerization of the PVA-based resin [I], it is preferably 50 to 3,000, particularly preferably 100 to 2,000, further preferably 200 to 1,000, and particularly preferably 200 to 500. If such an average degree of polymerization is too low, the protective colloidal ability during emulsion polymerization is insufficient, so that the polymerization tends to be difficult to proceed stably. If it is too high, the reaction system becomes unstable due to thickening during polymerization, resulting in dispersion stability. There is a tendency to decline.

In addition, in the present invention, the average degree of polymerization can be calculated according to the method of calculating the average degree of polymerization described in JIS K 6726 (1994).

In the present invention, the PVA-based resin [I] refers to PVA itself or, for example, modified by various modified species, and the degree of modification is usually 20 mol% or less, preferably 15 mol% or less. , More preferably 10 mol% or less.

Examples of the modified PVA-based resin include anionic-modified PVA-based resins modified with anionic groups including carboxylic acid groups, sulfonic acid groups, and phosphoric acid groups, cationic-modified PVA-based resins modified with cationic groups such as quaternary ammonium groups, and acetacetyl groups. , A modified PVA-based resin modified with various functional groups including a diacetoneacrylamide group, a mercapto group, and a silanol group, and a PVA-based resin containing a 1,2-diol structural unit in the side chain.

As the PVA-based resin [I] in the present invention, a PVA-based resin containing a 1,2-diol structural unit in the side chain is preferable from the viewpoint of excellent dispersion stability when the acrylic acid ester monomer is polymerized, and particularly preferably Is a PVA-based resin containing a 1,2-diol structural unit represented by the following general formula (1).

(General formula 1)

(In formula (1), R ¹ to R ⁶ each independently represent a hydrogen atom or an organic group, and X represents a single bond or a bonded chain.)

In the general formula (1), R ¹ to R ⁶ each independently represent a hydrogen atom or an organic group. It is preferable that all of R ¹ to R ⁶ are hydrogen atoms, but an organic group may be used as long as it is an amount that does not significantly impair the resin properties. Although it does not specifically limit as said organic group, For example, a C1-C4 alkyl group, such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, is preferable, If necessary, it may have a substituent such as a halogeno group, a hydroxyl group, an ester group, a carboxylic acid group, or a sulfonic acid group.

In the general formula (1), X is a single bond or a bonded chain, and it is preferable that it is a single bond from the viewpoints of set retention, no stickiness, and familiarity with hair. The bonding chain is not particularly limited, but hydrocarbons such as alkylene, alkenylene, alkynylene, phenylene, and naphthylene (these hydrocarbons may be substituted with halogens such as fluorine, chlorine, and bromine); O-,-(CH ₂ O) _m －,-(OCH ₂ ) _m －,-(CH ₂ O) _m CH ₂ －,-CO-,-COCO-,-CO(CH ₂ ) _m CO-,- CO(C ₆ H ₄ )CO-,-S-,-CS-,-SO-,-SO ₂ -,-NR-, -CONR-, -NRCO-, -CSNR-, -NRCS-, -NRNR- ,-HPO ₄ －,-Si(OR) ₂ －,-OSi(OR) ₂ －,-OSi(OR) ₂ O-,-Ti(OR) ₂ -,-OTi(OR) ₂ －,-OTi( OR) ₂ O-, -Al(OR)-, -OAl(OR)-, -OAl(OR)O-, etc. are mentioned (R is each independently an arbitrary substituent, a hydrogen atom and an alkyl group are preferable, , And m is a natural number). Among them, an alkylene group having 6 or less carbon atoms, particularly a methylene group, or -CH ₂ OCH ₂ -is preferable from the viewpoints of viscosity stability and heat resistance during production.

The PVA-based resin containing the 1,2-diol structural unit represented by the formula (1) is, for example, (I) saponified a copolymer of vinyl acetate and 3,4-diacetoxy-1-butene. Method, (II) saponification and decarboxylation of a copolymer of vinyl acetate and vinyl ethylene carbonate, (III) vinyl acetate and 2,2-dialkyl-4-vinyl-1,3-dioxolone It can be obtained by saponifying and deketalizing the copolymer, (IV) saponifying a copolymer of vinyl acetate and glycerin monoaryl ether.

The content rate of the 1,2-diol structural unit in the PVA-based resin containing the 1,2-diol structural unit represented by formula (1) is preferably 1 to 15 mol%, and particularly preferably 1 to 12 mol% , More preferably 2 to 10 mol%, particularly preferably 2 to 9 mol%. If the content of the 1,2-diol structural unit is too low, the mechanical stability of the emulsion tends to decrease, and if it is too high, the stability during polymerization tends to decrease, making it difficult to obtain a stable emulsion with high nonvolatile content. .

Further, the content of side chain 1,2-diol unit in the PVA-based resin is, ¹ H-NMR spectrum of what a completely saponified PVA can be obtained from (solvent:: DMSO-d6, internal standard tetramethylsilane), specifically May be calculated from the peak area derived from the hydroxyl proton, methine proton, and methylene proton in the 1,2-diol unit, the methylene proton of the main chain, and the proton of the hydroxyl group linked to the main chain.

Further, the average saponification degree of the PVA-based resin containing the 1,2-diol structural unit represented by the formula (1) is preferably 85 mol% or more, more preferably 86.5 to 99.3 mol%, particularly preferably 95 mol% It is -99 mol%. If such a degree of saponification is too small, the stability of the emulsion during polymerization tends to decrease, making it difficult to obtain the desired emulsion.

In addition, the average degree of polymerization of the PVA-based resin containing the 1,2-diol structural unit represented by formula (1) is preferably 50 to 3,000, more preferably 100 to 2,500, further preferably 200 to 2,000, particularly Preferably it is 200 to 500. If such an average degree of polymerization is too small, it tends to be difficult to industrially manufacture a PVA-based resin, and if it is too large, the viscosity of the emulsion tends to become too high or the polymerization stability of the emulsion tends to decrease.

In addition, in the present invention, the PVA-based resin [I] is usually made into an aqueous solution using an aqueous medium, and this is used for the process of emulsion polymerization. Here, the aqueous medium refers to water or an alcoholic solvent mainly composed of water, and preferably refers to water.

Although it does not specifically limit about the amount (non-volatile content) of the PVA-type resin [I] in this aqueous solution, it is preferable that it is 5-30 weight% from a viewpoint of ease of handling.

<Acrylic resin (A)>

The acrylic resin (A) in the present invention is obtained by polymerizing a monomer component containing a (meth)acrylic monomer (a1) as a main component. The main component is preferably 40% by weight or more, more preferably 50% by weight or more, particularly preferably 60% by weight or more, and even more preferably 70% by weight or more with respect to the whole monomer component.

As the (meth)acrylic monomer (a1), for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl Aliphatic types such as (meth)acrylate, 2-ethylhexyl (meth)acrylate, cyclohexyl (meth)acrylate, lauryl (meth)acrylate, octyl (meth)acrylate, and stearyl (meth)acrylate (Meth)acrylate-based monomers, aromatic (meth)acrylate-based monomers such as phenoxy (meth)acrylate, trifluoroethyl (meth)acrylate, and the like. In addition, these can be used alone or in combination of two or more. Among these, an aliphatic (meth)acrylate-based monomer having 1 to 18 carbon atoms in the alkyl group is preferred, and particularly preferably an aliphatic-based (meth)acrylate-based monomer having 1 to 12 carbon atoms in the alkyl group from the viewpoint of hair sensation and reinvention. It is a (meth)acrylate-based monomer, More preferably, it is an aliphatic (meth)acrylate-based monomer having 4 to 12 carbon atoms of the alkyl group, and particularly preferably n-butyl acrylate and 2-ethylhexyl acrylate. Further, a combination of 2-ethylhexyl acrylate and methyl methacrylate, or a combination of n-butyl acrylate and methyl methacrylate can also be suitably used.

Further, the (meth)acrylic monomer (a1) may be copolymerized with a functional group-containing monomer (a2), and as the functional group-containing monomer (a2), for example, a monomer having two or more vinyl groups in the molecular structure, glycidyl-containing A monomer, an aryl group-containing monomer, a hydrolyzable silyl group-containing monomer, an acetacetyl group-containing monomer, a hydroxyl group-containing monomer, a carboxyl group-containing monomer, and the like. Among these, it is preferable to copolymerize a monomer having two or more vinyl groups or a hydrolyzable silyl group-containing monomer in the molecular structure from the viewpoint of improving the water washability without deteriorating the hairdressing property.

As a monomer having two or more vinyl groups in the molecular structure, for example, divinylbenzene, diarylphthalate, triaryl cyanurate, triaryl isocyanurate, ethylene glycol di(meth)acrylate, 1,2 -Propylene glycol di(meth)acrylate, 1, 3-propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1, 6-hexinediol di(meth)acrylate, neopentyl Glycidyldi(meth)acrylate, trimethylolpropane tri(meth)acrylate, aryl(meth)acrylate, etc. are mentioned. Among these, ethylene glycol di(meth)acrylate, 1,2-propylene glycol di(meth)acrylate, 1,3-propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexinediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and trimethyrolpropane tri(meth)acrylate are good in copolymerization with (meth)acrylate-based monomers. desirable.

Examples of the glycidyl group-containing monomer include glycidyl (meth)acrylate, glycidyl (meth)aryl ether, and 3,4-epoxycyclohexyl (meth)acrylate.

Examples of the aryl group-containing monomer include a monomer having two or more aryl groups such as triaryloxyethylene, diaryl maleate, triaryl cyanurate, triaryl isocyanurate, and tetraaryloxyethane, and arylglycy. Diether, aryl acetate, and the like.

Examples of the hydrolyzable silyl group-containing monomer include vinyl-based silyl group-containing monomers such as vinyl trimethoxysilane, vinyl triethoxysilane, vinyl tris (β-methoxyethoxy) silane, and vinylmethyldimethoxysilane. ;Γ-(meth)acryloxypropyltrimethoxysilane, γ-(meth)acryloxypropylmethyldimethoxysilane, γ-(meth)acryloxypropyltriethoxysilane, γ-(meth)acryloxypropylmethyl And (meth)acryloxy-based silyl group-containing monomers such as diethoxysilane. Among these, a (meth)acryloxy-based silyl group-containing monomer is preferable from the viewpoint of excellent copolymerization with a (meth)acrylate-based monomer (a1).

Examples of the acetacetyl group-containing monomer include vinyl acetic acid, aryl acetic acid, aryl diacetate, acetacetoxyethyl (meth)acrylate, acetacetoxyethylcrotnath, and acetacetoxypropyl. (Meth)acrylate, acetacetoxypropylcrotnath, 2-cyanoacetoxyethyl (meth)acrylate, etc. are mentioned.

Examples of the hydroxyl group-containing monomer include (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate. And 2-hydroxyethyl acrylate and 2-hydroxyethyl methacrylate are preferable from the viewpoints of protective colloidal action and water-washability during emulsion polymerization.

Examples of the carboxyl group-containing monomer include (meth)acrylic acid, acriric acid dimer, crotonic acid, maleic acid, maleic anhydride, pmaric acid, citraconic acid, gluconic acid, itaconic acid, acrylamide N-glycolic acid, Cinnamic acid and the like are mentioned. Among these, acrylic acid and methacrylic acid are preferable from the viewpoints of protective colloidal action and water washability during emulsion polymerization.

The content ratio of the functional group-containing monomer (a2) is preferably 0.01 to 10% by weight, particularly preferably 0.05 to 5% by weight, and still more preferably 0.1 to 3% by weight, based on the entire monomer component. When such a content ratio is too large, the acrylic resin becomes too hard, and sufficient adhesive force does not appear, and the hairdressing property tends to decrease, and when it is too small, the effect of water washing property tends to be difficult to understand.

In addition, when the functional group-containing monomer (a2) is a monomer having two or more vinyl groups in the molecular structure, it is preferably 0.01 to 5% by weight, particularly preferably 0.05 to 3% by weight, based on the entire monomer component. More preferably, it is 0.1 to 1 weight%.

In addition, as long as the effects of the present invention are not impaired, a small amount of styrene-based monomers such as styrene and α-methylstyrene; vinyl formate, vinyl acetate, vinyl propionate, vinyl valerate, vinyl butyrate, vinyl isobutyrate, Vinyl ester-based monomers, such as vinyl pivalate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl benzoate, vinyl basatixate, and 2-ethyl hexanoate, may be used.

For the acrylic resin emulsion according to the present invention, in addition to the above-described monomer components, other components may be further used as necessary. As such other components, it can be appropriately selected according to the purpose, and examples thereof include a polymerization initiator, a polymerization regulator, an auxiliary emulsifier, and a plasticizer.

As the polymerization initiator, those that can be used in ordinary emulsion polymerization can be used, for example, inorganic peroxides such as potassium persulfate, sodium persulfate, and ammonium persulfate; organic peroxides, azo initiators, hydrogen peroxide, butyl peroxide And peroxides; and redox polymerization initiators in which these and reducing agents such as acidic sodium sulfite and L-ascorbic acid are combined. These can be used alone or in combination of two or more. Among these, ammonium persulfate and potassium persulfate are preferable because polymerization is easy.

As the polymerization regulator, it can be appropriately selected from known ones. As such a polymerization regulator, a chain transfer agent, a buffer, etc. are mentioned, for example.

Examples of the chain transfer agent include alcohols such as methanol, ethanol, propanol, and butanol; aldehydes such as acetaldehyde, propionaldehyde, n-butyl aldehyde, furfural, and benzaldehyde; and dodecylmercaptan, normal mer Mercaptans, such as captan, thioglycolic acid, octyl thioglycolate, and thioglycerol, etc. are mentioned. These can be used alone or in combination of two or more. The use of a chain transfer agent is effective from the viewpoint of stabilizing polymerization, and is preferably used in order to adjust the degree of polymerization of the acrylic resin.

Examples of the buffer include sodium acetate, ammonium acetate, dibasic sodium phosphate, sodium citrate, and the like. These can be used alone or in combination of two or more.

As the auxiliary emulsifier, any one that can be used for emulsion polymerization and is known to those skilled in the art can be used. Therefore, the auxiliary emulsifier is suitably selected from known ones such as anionic, cationic, and nonionic surfactants, water-soluble polymers having protective colloidal properties other than PVA-based resin [I], and water-soluble oligomers. You can choose.

Examples of the surfactant include anionic surfactants such as sodium lauryl sulfate and sodium dodecylbenzene sulfonate, and nonionic surfactants such as those having a pluronic structure or a polyoxyethylene structure. Can be lifted. Further, as the surfactant, a reactive surfactant having a radically polymerizable unsaturated bond in the structure can also be used. These can be used alone or in combination of two or more.

The use of the surfactant has an effect of smoothly proceeding the emulsion polymerization to make it easier to control (effect as an emulsifier) or to suppress the generation of defective particles or block-like substances occurring during polymerization. However, when many of these surfactants are used as an emulsifier, the graft rate tends to decrease. For this reason, in the case of using a surfactant, it is preferable that the amount used is an amount auxiliary to the PVA-based resin [I], that is, to be reduced as much as possible.

Examples of the water-soluble polymer having a protective colloidal ability other than the PVA-based resin [I] include PVA-based resins other than the PVA-based resin [I], hydroxyethyl cellulose, polyvinyl pyrrolidone, and methyl cellulose. I can. These are used alone or in combination of two or more. These are effective in that they change the viscosity of the emulsion by changing the thickening of the emulsion or the particle diameter of the emulsion.

As the water-soluble oligomer, for example, a polymer having a hydrophilic group such as a sulfonic acid group, a carboxyl group, a hydroxyl group, or an alkylene glycol group is preferable, and among them, a polymer or copolymer having a degree of polymerization of about 10 to 500 is very suitable. . Specific examples of the water-soluble oligomer include, for example, amide-based copolymers such as 2-methacrylamide-2-methylpropanesulfonic acid copolymer, sodium methacrylate-4-styrenesulfonate copolymer, and styrene/maleic acid copolymer, Melamine sulfonic acid formaldehyde condensate, poly(meth)acrylate, and the like. Further, specific examples thereof include a monomer having a sulfonic acid group, a carboxyl group, a hydroxyl group, an alkylene glycol group, or a water-soluble oligomer formed by copolymerizing a radically polymerizable reactive emulsifier, either alone or with another monomer. These are used alone or in combination of two or more.

As the plasticizer, an adipate plasticizer, a phthalic acid plasticizer, and a phosphoric acid plasticizer can be used.

The amount of use of these other components can be appropriately selected according to the purpose within the range not impairing the effects of the present invention.

<Method for producing acrylic resin emulsion>

Next, a method for producing the acrylic resin emulsion of the present invention will be described.

The acrylic resin emulsion of the present invention can be produced, for example, by emulsion polymerization of the above-described monomer component using PVA-based resin [I] as a dispersion stabilizer. In this polymerization process, an acrylic resin emulsion using PVA-based resin [I] as a dispersion stabilizer and dispersion-stabilized acrylic resin (A) as a dispersant is prepared.

In the present invention, the amount of PVA-based resin [I] used is preferably 0.01 to 40 parts by weight, particularly preferably 0.1 to 30 parts by weight, based on 100 parts by weight of the total monomer components constituting the acrylic resin (A), More preferably, it is 0.5 to 20 parts by weight. If the amount of the PVA-based resin [I] is too small, the amount of protective colloid during emulsion polymerization will be insufficient, and polymerization stability tends to decrease. If the amount is too large, the viscosity of the acrylic resin emulsion increases and the stability decreases. Tend to do.

Here, the total amount of the PVA-based resin [I] used is usually present in the acrylic resin emulsion formed by polymerization.

Usually, the emulsion polymerization is carried out using other components than those described above, such as a polymerization initiator, a polymerization regulator, an auxiliary emulsifier, etc., as needed, in addition to the PVA-based resin [I] and the monomer component. Moreover, the reaction conditions for polymerization can be appropriately selected according to the kind and purpose of the monomer.

As a method of emulsion polymerization, for example, a monomer dropping type emulsion polymerization method in which water and a PVA-based resin [I] are added to a reaction vessel, and the temperature is increased to drop a monomer component and a polymerization initiator; and Emulsifying monomer dropping type emulsion polymerization method in which the mixed monomer is previously dispersed and emulsified with water and water having a protective colloidal ability other than PVA-based resin [I] and/or PVA-based resin [I], and then the dispersing and emulsifying monomer is added dropwise. And the like, the emulsifying monomer dropping polymerization method is advantageous from the viewpoints of reactivity when using a hydrophobic monomer and control and control of the polymerization process. In addition, because of imparting stability to the emulsion or imparting water solubility and/or redispersibility to water, at the end of the polymerization reaction, a water-soluble polymer having a protective colloidal ability other than PVA-based resin [I] and/or PVA-based resin [I] is added later. It is also possible to do.

When the emulsion polymerization process is described in more detail, it is as follows.

In the monomer dropwise emulsion polymerization, for example, first, water, a PVA-based resin [I], and, if necessary, an auxiliary emulsifier are added to a reaction vessel, and the temperature is raised (usually 40 to 90°C), and then the monomer component is A portion and a polymerization initiator are added to this reaction vessel to perform initial polymerization. Subsequently, the remaining monomer components are added to the reaction vessel while collectively or dropwise, and polymerization proceeds while adding a polymerization initiator again if necessary. When it is determined that the polymerization reaction has been completed, the reaction vessel is cooled to take out the target acrylic resin emulsion.

In the emulsified monomer dropping emulsion polymerization method, for example, first, water, if necessary, a PVA-based resin [I], and an auxiliary emulsifier are added to the reaction vessel, and the temperature is raised (usually 40 to 90°C). , A water-soluble polymer having a protective colloidal ability other than PVA-based resin [I] and/or PVA-based resin [I], and if necessary, add an auxiliary emulsifier, part of the monomer component emulsified and dispersed with water, and a polymerization initiator to this reaction vessel. To carry out initial polymerization. Subsequently, the remaining monomer components are added to the reaction vessel while collectively or dropwise, and polymerization proceeds while adding a polymerization initiator again if necessary. When it is judged that the polymerization reaction is complete, the reaction vessel can be cooled to take out the target acrylic resin emulsion.

In addition, it is also possible to carry out the above-described method in which the initial polymerization is not carried out, and the total amount of the monomer component and the polymerization initiator are added dropwise to the reaction vessel. In addition, when the reaction temperature is less than 70°C, it is preferable to use a redox polymerization reaction system in combination with a reducing agent from the viewpoint of smooth reaction.

In the present invention, the acrylic resin emulsion obtained by emulsion polymerization is typically uniform milky white, and the average particle diameter of the acrylic resin (A) in the acrylic resin emulsion is preferably 0.2 to 2 µm, more preferably It is 0.3-1.5㎛.

In addition, here, the average particle diameter can be measured by a conventional method, for example, a laser analysis/scattering particle size distribution measuring device "LA-950S2" (manufactured by Horiba Seisakusho Co., Ltd.).

The acrylic resin (A) in the acrylic resin emulsion preferably has a glass transition temperature of 70°C or less, particularly preferably 40°C or less, more preferably 20°C or less, and even more preferably 0°C or less. When such a glass transition temperature is too high, the acrylic resin becomes hard and breaks when it dries, and there is a tendency that the re-fermentation performance decreases. In addition, the lower the glass transition temperature is, the more adhesive the polymer is, the better the recalculation property tends to be, and is preferable, but the lower limit is usually -80°C, preferably -70°C. In addition, the higher the content ratio of the PVA-based resin [I] is, the lower the glass transition temperature of the acrylic resin (A) is, the more preferable it is from the viewpoint of redeposition.

The glass transition temperature of the acrylic resin (A) in the present invention is a value that can be calculated by calculating the glass transition temperature of a homopolymer composed of each polymerization component constituting the acrylic resin by the formula of Fox, and the acrylic resin (A It can be adjusted by appropriately adjusting the weight ratio of each polymerization component constituting ). In addition, when a functional group-containing monomer is used in combination, it may be calculated by Fox's formula based on the main monomer components excluding such a functional group-containing monomer.

In addition, in the present invention, at least a part of the PVA resin [I] is grafted onto the acrylic resin (A), so that the difference in the measured values in the storage stability and adhesion strength measurement of the acrylic resin emulsion itself obtained before drying It is preferable from the point of becoming less.

When PVA-based resin [I] is grafted onto the acrylic resin (A), the value (W) represented by the following formula (2) is preferably 90% by weight or less, more preferably 85% by weight or less, further It is preferably 80% by weight or less. In addition, the lower limit is usually 1% by weight, preferably 5% by weight, and more preferably 10% by weight. Such a value serves as a standard for the degree of grafting, and if this value is too low, the degree of grafting is low, the protective colloidal action during emulsion polymerization is lowered, and polymerization stability tends to decrease. , There is a tendency that it is difficult to produce a stable emulsion at a high concentration.

The value W of Formula (2) is calculated as follows. That is, the target emulsion or the like is dried at room temperature to prepare a film, and the film is extracted in boiling water and acetone for 8 hours, respectively, and the resin that has not been grafted is removed. In this case, the absolute dry weight of the film before extraction is w ₁ (g), and the absolute dry weight of the film after extraction is w ₂ (g), and is determined by the following formula (2).

W (% by weight) = (w ₂ )/(w ₁ )×100... (2)

As a method of adjusting the value (W) of the above formula (2), the emulsion polymerization temperature is changed (when it is increased, (W) is high, and when it is decreased (W) is decreased), a very small amount of persulfate used as a polymerization catalyst, etc. A method of using in combination with a reducing agent (for example, acidic sodium sulfite, etc.) ((W) increases), etc. are mentioned.

In the present invention, various additives may be added again as necessary to the acrylic resin emulsion after emulsion polymerization. Examples of such additives include organic pigments, inorganic pigments, water-soluble additives, pH adjusters, preservatives, antioxidants, and the like.

In this way, the acrylic resin emulsion of the present invention is obtained, and in its use, it is preferably adjusted to 0.1 to 65% by weight as a nonvolatile content. In addition, when using such an acrylic resin emulsion as a hairdressing agent, when used in combination with other compounding components (resin or additives described later), the nonvolatile content is usually 30 to 60% by weight, and the use of other resins or additives is not recommended. It is preferable because it is difficult to limit. In addition, when such an acrylic resin emulsion is used alone as a hairdressing agent, it is preferable that the non-volatile content is usually 1 to 10% by weight, since it is easy to uniformly apply to hair.

In this way, the acrylic resin emulsion of the present invention is obtained. Such an acrylic resin emulsion is used for a hairdressing agent, and a hairdressing agent using the emulsion exhibits desired performance.

The hairdressing agent of the present invention may be one in which an acrylic resin emulsion is used alone, or in combination with an acrylic resin emulsion and various blending agents.

In the hairdressing agent of the present invention, the acrylic resin emulsion for a hairdressing agent of the present invention preferably contains 1% by weight or more (in terms of solid content) in the hairdressing agent, more preferably 3% by weight or more (in terms of solid content), and more preferably It is preferably 5% by weight or more (in terms of solid content). In addition, the upper limit is usually 70% by weight (in terms of solid content), preferably 60% by weight (in terms of solid content), and more preferably 50% by weight (in terms of solid content). When the acrylic resin emulsion for a hairdressing agent of the present invention is too small, the hairdressing power tends to decrease, and when too large, the cleaning property tends to decrease.

In the hairdressing agent of the present invention, in the acrylic resin emulsion, various blending components used as known general hairdressing agents, such as emulsions, polyhydric alcohols, lower alcohols, surfactants, ultraviolet absorbers, fragrances, antioxidants, moisturizers , Refreshing agents, vitamins, plant extracts, etc. can be prepared by appropriately blending according to the purpose.

Examples of the emulsion include oils and fats such as sunflower oil, cottonseed oil, soybean oil, olive oil, palm oil, castor oil, jojoba oil, camellia oil, and mink oil; beeswax, carnauba wax, candelilla wax, rice bran wax , Shellac wax, light brain oil (spermaceti), lanolin and other waxes; ceresin, paraffin wax, liquid paraffin, liquid isoparaffin, microcrystalline wax, polyethylene powder, polyethylene wax, Fischer-Tropsch wax, vaseline, squalene, and other hydrocarbons Yu; lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, behenic acid, 2-ethyl butanoic acid, isopentanoic acid, 2-methylpentanoic acid, 2-ethylpentanoic acid, isostearic acid, 12-hydroxystearic acid Higher fatty acids such as lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, oleyl alcohol, lanolin alcohol, behenyl alcohol, and setstearyl alcohol; ethyl oleate, isopropyl myristate, palmitic acid Isopropyl, myristate myristate, cetyl palmitate, oleyl oleate, octyldodecyl myristate, octyldodecyl oleate, ethyl isostearate, isostearate isopropyl, 2-ethylhexanoate cetyl, 2-ethylhexanoic acid set Stearyl, glyceryl tri2-ethylhexanoate, glyceryl triisopalmitate, pentaerythritol tetra2-ethylhexanoate, isocetyl octanoate, isostearyl octanoate, isostearyl isostearate, octyldodecyl isostearate , Fatty acid ester oils such as dimethyloctanoate octyldodecyl; methylpolysiloxane, highly polymerized methylpolysiloxane, methylphenylpolysiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclo Silicone oils, such as hexasiloxane, methylcyclo polysiloxane, alcohol-modified silicone, alkyl-modified silicone, amino-modified silicone, and epoxy-modified silicone, etc. are mentioned. These may be used alone or in combination of two or more.

The content of such an oil agent is usually preferably 0.5 to 50% by weight, particularly preferably 1 to 40% by weight, based on the total amount of the hairdressing agent from the viewpoint of emulsification. In addition, from the viewpoint of a lot of oiliness or stickiness of the hairdressing agent, it is preferable to set the content as small as possible, but by using the acrylic resin emulsion of the present invention, the amount of the oil agent can be reduced or not used.

Examples of the polyhydric alcohol include ethylene glycol, dipropylene glycol, propylene glycol, isoprene glycol, glycerin, diglycerin, 1,3-butylene glycol, 1,2-pentanediol, 1,2-hexanediol, 1,2-octanediol, 1,2-decanediol, etc. can be illustrated. These may be used alone or in combination of two or more.

The content of such a polyhydric alcohol is preferably 0.1 to 20% by weight, particularly preferably 0.5 to 15% by weight, based on the total amount of the hairdressing agent from the viewpoint of feeling of use.

The acrylic resin emulsion for a hairdressing agent of the present invention is used as a liquid-type hairdressing agent by diluting an acrylic resin emulsion with water, polyhydric alcohol, lower alcohol, etc., or using the oil as a surfactant and water in an acrylic resin emulsion. It is possible to mix emulsified dispersion and use it as a viscous liquid type or a cream type hairdressing agent.

Using the hairdressing agent containing the acrylic resin emulsion for hairdressing agents of the present invention, hairdressing can be performed, for example, as follows. The acrylic resin emulsion for a hairdressing agent of the present invention containing the acrylic resin (A) dispersion-stabilized by polyvinyl alcohol resin [I] is applied to the hair for an effective hairdressing amount, and during or before and after the acrylic resin emulsion for a hairdressing agent is applied. Eh, prepare the hair in the desired shape. By hairdressing in this way, it is possible to easily form a desired hair shape.

(Example)

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless the gist of the present invention is exceeded. In addition, in Examples, "part" and "%" mean a weight basis.

First, various acrylic resin emulsions were prepared in the following manner. In addition, the nonvolatile content and viscosity of the acrylic resin emulsion were measured by the following method, and the glass transition temperature was measured according to the method described above.

<Non-volatile content>

The flat shape specified in JIS R 3503 (1994) is accurately measured by spreading 1 g of a sample on a plate container made of aluminum foil molded on the same bottom area as a weighing bottle 50 mm x 30 mm. Place the container in the center of a thermostat, dry it at 105°C±2°C for 60±5 minutes, cool it in a desiccator, and weigh the container. And it was calculated by the following equation.

N=(Wd/Ws)×100

(Wherein, N is the non-volatile content (%), Wd is the weight of the sample after drying (g), and Ws is the weight of the sample before drying (g).)

<Viscosity>

It is measured with a Brookfield viscometer (for example, a BL type viscometer manufactured by Tokyo Keiki Inc.). Put about 500 ml of sample into the sample container so that no air bubbles are mixed, and hold the sample container so that the liquid level of the sample is lower than that of the heat transfer medium of the constant temperature bath. If necessary, stir with a glass rod and measure the sample temperature at 23±1℃. Viscosity was calculated by the following equation (two significant figures).

η=Kn×θ

(Where η is the viscosity (mPa·s), Kn is the conversion multiplier attached to the viscometer, and θ is the average of the viscometer indication values of the two measurements).

<Example 1: Preparation of acrylic resin emulsion (1)>

In a reaction vessel made of SUS equipped with a cooling tube and a stirring blade, a PVA resin containing 1,2-diol structural units in the side chain in deionized water (92 parts) (average saponification degree 99 mol%, average polymerization degree 300, side chain Content of 1,2-diol structural unit 8 mol% / Nippon Kosei Kogyo Co., Ltd.) 10 parts, sodium hydrogen sulfite 0.2 parts, sodium carbonate and trihydrate 0.4 parts were completely dissolved, and the temperature was raised to 75°C. 77 parts of deionized water, 5 parts of unmodified PVA-based resin (manufactured by Nippon Kosei Kogyo Co., Ltd.; brand name "Gosenol GL05"), 100 parts of 2-ethylhexyl acrylate emulsified (i) and 10% APS (and An aqueous solution (ii) of 2.7 parts (ii) of ammonium sulfate) was prepared, and 10% of (i) and 30% of (ii) were first added to the reaction vessel, followed by reaction for 45 minutes. Then, 90% of the remainder of (i) and 60% of (ii) were added dropwise over 3.5 hours, followed by polymerization at 75 to 78°C. After the dropping was completed, 5% of (ii) was added, the temperature was maintained for 1.5 hours, and 5% of (ii) was added again to maintain the temperature for 1.5 hours. Then, it cooled and obtained the acrylic resin emulsion (1) (non-volatile content 46%; viscosity 125 mPa·s (B type viscometer 12 rpm, 23°C); glass transition temperature (Tg) of acrylic resin = -70°C). The acrylic resin emulsion (1) was dispersed and stabilized.

<Example 2: Preparation of acrylic resin emulsion (2)>

In Example 1, 100 parts of 2-ethylhexyl acrylate was changed to 90 parts of 2-ethylhexyl acrylate and 10 parts of methyl methacrylate, and again as an unmodified PVA-based resin "Gosenol GL05" (trade name, Nippon Kosei University Acrylic resin emulsion (2) (non-volatile content 43%; viscosity 160 mPa·s) was carried out in the same manner as in Example 1 except that the product name was changed to “Gosenol EG05” from Nippon Kosei Kogyo Co., Ltd. (B type viscometer 12 rpm, 23 degreeC); The glass transition temperature (Tg) of an acrylic resin = -60 degreeC) was obtained. The acrylic resin emulsion (2) was dispersed and stabilized.

<Example 3: Preparation of acrylic resin emulsion (3)>

In Example 2, the same procedure as in Example 2 was carried out except for adding 0.3 parts of ethylene glycol dimethacrylate (manufactured by Mitsubishi Rayon; brand name "Acryester ED") as an acrylic monomer again, and an acrylic resin emulsion (3 ) (Non-volatile content 44%; viscosity 210 mPa·s (B type viscometer 12 rpm, 23°C); glass transition temperature (Tg) of acrylic resin = -60°C) was obtained. The acrylic resin emulsion (3) was dispersed and stabilized.

<Example 4: Preparation of acrylic resin emulsion (4)>

In Example 1, 100 parts of 2-ethylhexyl acrylate was changed to 75 parts of 2-ethylhexyl acrylate and 25 parts of methyl methacrylate, and again as an unmodified PVA-based resin "Gosenol GL05" (trade name, Nippon Kosei University Acrylic resin emulsion (4) (non-volatile content 46%; viscosity 540 mPa·s) was carried out in the same manner as in Example 1, except that the product was changed from Nippon Kosei Kogyo Co., Ltd. to the brand name "Gosenol EG05". (B type viscometer 12 rpm, 23 degreeC); The glass transition temperature (Tg) of an acrylic resin = -43 degreeC) was obtained. The acrylic resin emulsion (4) was dispersed and stabilized.

<Example 5: Preparation of acrylic resin emulsion (5)>

In Example 4, the same procedure as in Example 4 was carried out except for adding 0.2 parts of acryester ED (ethylene glycol dimethacrylate) as an acrylic monomer, and acrylic resin emulsion (5) (non-volatile content 43%; viscosity 420) mPa·s (B-type viscometer 12 rpm, 23°C); the glass transition temperature (Tg) of an acrylic resin (Tg) = -43°C) was obtained. The acrylic resin emulsion (5) was dispersed and stabilized.

<Example 6: Preparation of acrylic resin emulsion (6)>

In Example 1, 100 parts of 2-ethylhexyl acrylate was changed to 60 parts of 2-ethylhexyl acrylate and 40 parts of methyl methacrylate, and again as an unmodified PVA-based resin "Gosenol GL05" (trade name, Nippon Kosei University Acrylic resin emulsion (6) (non-volatile content 44%; viscosity 470 mPa·s) in the same manner as in Example 1, except for changing the product from Nippon Kosei Kogyo Co., Ltd. to the brand name "Gosenol EG05" B type viscometer 12 rpm, 23 degreeC); the glass transition temperature (Tg) of an acrylic resin = -24 degreeC) was obtained. The acrylic resin emulsion (6) was dispersed and stabilized.

<Example 7: Preparation of acrylic resin emulsion (7)>

In a reaction vessel made of SUS equipped with a cooling tube and a stirring blade, 92 parts of deionized water, 0.2 parts of sodium hydrogen sulfite, and 0.4 parts of sodium carbonate and trihydrate were completely dissolved, and the temperature was raised to 75°C. PVA-based resin containing 77 parts of deionized water in advance and 1,2-diol structural units in the side chain (average saponification degree 89 mol%, average polymerization degree 340, content of 1,2-diol bonds in side chains 3 mol% / Nippon Kosei University) (Manufactured by Co., Ltd.) 4 parts, n-butyl acrylate 55 parts and methyl methacrylate 45 parts emulsified (i) and 10% APS aqueous solution 2.7 parts (ii) were prepared, and in the reaction vessel, first (i) 10% of and 30% of (ii) were added and reacted for 45 minutes. Then, 90% of the remainder of (i) and 60% of (ii) were added dropwise over 3.5 hours, followed by polymerization at 75 to 78°C. After the dropping was completed, 5% of (ii) was added, the temperature was maintained for 1.5 hours, and 5% of (ii) was added again to maintain the temperature for 1.5 hours. Then, it cooled and obtained the acrylic resin emulsion (7) (non-volatile content 45%; viscosity 600 mPa·s (B-type viscometer 12 rpm, 23° C.); glass transition temperature (Tg) = 3° C.) of the acrylic resin. The acrylic resin emulsion (7) was dispersed and stabilized.

<Example 8: Preparation of acrylic resin emulsion (8)>

In a reaction vessel made of SUS equipped with a cooling tube and a stirring blade, a PVA resin containing 169 parts of deionized water and 1,2-diol structural units in the side chain (average saponification degree 99 mol%, average polymerization degree 300, side chain 1, 2-diol bond content 8 mol% / Nippon Kosei Kogyo Co., Ltd.) 7 parts, sodium hydrogen sulfite 0.2 parts, sodium carbonate and trihydrate 0.4 parts were completely dissolved, and the temperature was raised to 75°C. A mixture of 54.7 parts of n-butyl acrylate, 44.8 parts of methyl methacrylate and 0.5 parts of 2-acetoxyethyl methacrylate (i) and 2.7 parts of 10% APS aqueous solution (ii) were prepared, and in a reaction vessel, 100% of (i) and 90% of (ii) were added dropwise over 4.5 hours, followed by polymerization at 75 to 78°C. After the dropping was completed, 5% of (ii) was added, the temperature was maintained for 1.5 hours, and 5% of (ii) was added again to maintain the temperature for 1.5 hours. Then, it cooled and obtained the acrylic resin emulsion (8) (non-volatile content 45%; viscosity 500 mPa·s (B type viscometer 12 rpm, 23° C.); glass transition temperature (Tg) = 9° C.) of the acrylic resin. The acrylic resin emulsion (8) was dispersed and stabilized.

<Example 9: Preparation of acrylic resin emulsion (9)>

In Example 4, the same procedure as in Example 4 was carried out except for adding 0.05 parts of KBM 503 (γ-methacryloxypropyltrimethoxysilane) as a monomer component, and the acrylic resin emulsion (9) (non-volatile content 44%; Viscosity of 550 mPa·s (B-type viscometer 12 rpm, 23°C); Glass transition temperature (Tg) of acrylic resin = -43°C) was obtained. The acrylic resin emulsion (9) was dispersed and stabilized.

<Example 10: Preparation of acrylic resin emulsion (10)>

To 100 parts of the acrylic resin emulsion (1) obtained in Example 1, 10 parts of a 20% aqueous solution of an unmodified PVA-based resin (manufactured by Nippon Kosei Kogyo Co., Ltd.; brand name ``Gosenol GL05'') was added, and an acrylic resin emulsion ( 10) (Non-volatile content 44%; viscosity 140 mPa·s (B type viscometer 12 rpm, 23°C); glass transition temperature (Tg) of acrylic resin = -70°C) was obtained. The acrylic resin emulsion (10) was being dispersed and stabilized.

<Comparative Example 1>

PVA-based resin containing 1,2-diol structural units in the side chain (average saponification degree 99 mol%, average polymerization degree 300, content of 1,2-diol bonds in the side chain 8 mol% / manufactured by Nippon Kosei Kogyo Co., Ltd.) Diluted with deionized water, 45% of non-volatile matter, and 3% PVA-based resin solution were prepared. The state of the PVA-based resin solution of Comparative Example 1 was dispersed and stabilized.

<Comparative Example 2>

Acrylic resin emulsion prepared by emulsion polymerization using only anionic surfactant (manufactured by Nippon Kosei Kogyo Co., Ltd., brand name "Coponyl WU-6406"; non-volatile content 56%; viscosity 1200 mPa·s; glass transition temperature of acrylic resin- 68° C.) was diluted with deionized water to prepare an acrylic resin emulsion of 45% and 3% of nonvolatile matter. The acrylic resin emulsion state of Comparative Example 2 was dispersion-stabilized.

<Preparation of hairdressing agent test solution (A)>

In Examples 1 to 10, acrylic resin emulsions (1) to (10) were diluted with deionized water so that the non-volatile content was 3%, respectively, to obtain a hairdressing agent test solution (A). For the above Comparative Examples 1 and 2, a non-volatile content of 3% was used, and a hairdressing agent test solution (A) was obtained.

Using the hairdressing agent test solution (A), hair-dressing performance (setting force), re-hairing performance (resetting force), and tactile sensitivity were evaluated as follows.

<hairdressing performance (set power)>

0.5 g of the hairdressing agent test solution (A) was evenly applied to the hair bundle (length 20 cm × weight 1.2 g; hair hair salon) with a dropper, and again spread more evenly with a finger wearing a vinyl glove. After arranging with fingers so that the width of the bundle is about 1cm, dry it in a blow dryer for 100℃×1 minute, hold the hair end at an angle of about 45° from just above with the tied side facing down, and the hair strands are fixed. Whether it was a sensory evaluation. The evaluation method is as follows.

(Evaluation standard)

○… Even if you shake it a little, it remains neat and styled.

△... Shake it slightly to spread the ends of the hair a little.

×… Untidy, or slightly shaken, the ends of the hair will scatter.

In addition, in the above evaluation, "o" means excellent in performance, and "Δ" is practically acceptable. Also, "x" indicates poor performance.

＜Reshaping performance (reset power)＞

After performing the hairdressing evaluation, the hair bundle was loosened with a finger, and the hair bundle was again scattered with a comb, and then the hair bundle state when the hair bundle was formed again with the finger was sensory evaluated. The evaluation method is as follows.

(Evaluation standard)

○… Hair is re-arranged (haired)

△... It is trimmed, but the hair is slightly spread.

×… It does not become a hair follicle and is not haired.

In addition, in the above evaluation, "o" means excellent in performance, and "Δ" is practically acceptable. Also, "x" indicates poor performance.

<touchability>

About the tidy feeling of hair at the time of the said re-hairing performance evaluation, the feeling of touch with a finger|toe was evaluated. The evaluation method is as follows.

(Evaluation standard)

○… It is moist and smooth.

△... It's a little fuzzy.

×… It is quite fuzzy.

In addition, in the above evaluation, "o" means excellent in performance, and "Δ" is practically acceptable. Also, "x" indicates poor performance.

<Preparation of hairdressing agent test solution (B)>

For Examples 1 to 10, acrylic resin emulsions (1) to (10) were used as they were, and for Comparative Examples 1 and 2, a hairdressing agent test solution (B) using 45% non-volatile content, respectively. I did it.

<Cleaning performance>

The hairdressing agent test solution (B) was applied to a 50 µm-thick PET (polyethylene terephthalate) film with a 40 µm applicator and dried at 100° C. for 5 minutes to obtain a coating film having a thickness of about 15 µm (when dried). On the coating film, drop 1 drop of deionized water with a dropper, and gently rub it 10 times (10 weeks) to draw a circle with a diameter of about 1 cm with your finger, Wes made of pulp (manufactured by Nippon Seiji Kuresia Co., Ltd., ``Kim Wipe" (registered trademark)), the degree of washing of the coating-form hairdressing agent solution was visually evaluated. The evaluation method is as follows.

(Evaluation standard)

○… It could be wiped off more than 70% and 100%.

△... More than 20% and less than 70% could be wiped off.

×… More than 0 and less than 20% could be wiped off.

In addition, in the above evaluation, "o" means excellent in performance, and "Δ" is practically acceptable. Also, "x" indicates poor performance.

From the above Examples 1 to 10, in the hairdressing agent using the acrylic resin emulsion dispersion-stabilized by the PVA-based resin of the present invention, the styling performance (hairdressing performance, re-hairing performance, tactile sensibility) and the performance to be cleaned are excellent in balance. Able to know.

On the other hand, in Comparative Example 1 in which a PVA-based resin was used as an aqueous solution, it was found that the hair-styling performance and the cleaning target performance were good, but the re-cutting property and the tactile feeling were poor. In addition, in Comparative Example 2 using an acrylic resin emulsion obtained using a non-PVA-based surfactant, the hair-dressing performance, re-hairing performance, and tactile sensibility were good, but the cleaning performance was poor, and as a hair-dressing agent, practically, there was a problem. You can see that it is a level.

Although the present invention has been described in detail and with reference to specific embodiments, it is clear to those skilled in the art that various changes and modifications can be added without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application filed on December 18, 2012 (Japanese Patent Application No. 2012-275244) and a Japanese patent application filed on August 23, 2013 (Japanese Patent Application No. 2013-173245), the contents of which are referred to here. Is incorporated as.

(Industrial availability)

Since the acrylic resin emulsion for a hairdressing agent of the present invention has excellent balance of styling performance (hairdressing performance, re-hairing performance, tactile feel) and cleaning performance, various blending agents can be used in combination, and can be used in various formulations. The application of is possible and useful.

Claims (7)

Contains acrylic resin (A) dispersed and stabilized by polyvinyl alcohol resin [I],
Polyvinyl alcohol-based resin [I] is a polyvinyl alcohol-based resin containing a side chain 1,2-diol structural unit represented by the following general formula (1), and the glass transition temperature of the acrylic resin (A) is -80°C to Acrylic resin emulsion for a hairdressing agent, characterized in that 40 ℃.
(General formula (1))

(In formula (1), R ¹ to R ⁶ each independently represent a hydrogen atom or an organic group, and X represents a single bond or a bonded chain.) The method according to claim 1,
An acrylic resin emulsion for a hairdressing agent in which the content of the side chain 1,2-diol structural units in the polyvinyl alcohol resin [I] containing the side chain 1,2-diol structural units represented by the above formula (1) is 1 to 15 mol%. . The method according to claim 1,
The acrylic resin (A) is obtained by polymerizing a monomer component containing 40% by weight or more of an aliphatic (meth)acrylate monomer having 4 to 12 carbon atoms in an alkyl group. A hairdressing agent containing the acrylic resin emulsion for a hairdressing agent according to any one of claims 1 to 3. A hairdressing method comprising a step of applying the acrylic resin emulsion for a hairdressing agent according to any one of claims 1 to 3 to the hair, and a step of arranging the hair into a desired shape during or before and after the application of the acrylic resin emulsion for a hairdressing agent. delete delete