JP2012149147A - Block polymer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a block polymer capable of being manufactured industrially advantageously, excellent in curl retention, flexibility and good finger combing, particularly satisfying both curl retention and good finger combing.SOLUTION: The block polymer is made by bonding two or more blocks composed of monomers having a vinylic functional group through a linking monomer having a radically polymerizable vinylic functional group and a non-radically polymerizable functional group, wherein the two or more blocks contain at least a first block and a second block having mutually different monomer compositions, and the acid value of the block polymer is in the range of ≥200 mgKOH/g and ≤700 mgKOH/g.

Description

  The present invention relates to a block polymer suitable for industrial production.

  Structure-controlled polymers, such as block polymers, may exhibit specific performance that cannot be obtained with random-structure polymers. For example, AB type block polymers and ABA type block polymers in which two blocks having different properties are connected in series are applied to polymer emulsifiers, thickeners, and the like. Further, in the sense of having a block site, it can be said that a graft polymer is a kind of block polymer, and a graft polymer obtained by using a macromonomer having a reactive functional group has also been proposed. Since each block site has a different property from other sites, it is possible to mix those that cannot be mixed normally or to have a strong aggregating action, so that specific performance can be achieved. It is expressed.

  These block polymers having specific performance have begun to be used in various fields, and are expected as means for simultaneously solving various requirements.

  Conventionally, as a method for producing an AB type block polymer or an ABA type block polymer, there are a living radical polymerization method and a method using a special polymer type initiator, but in the case of living radical polymerization, a catalyst is used. After the reaction, it is necessary to remove the used catalyst, and there is a problem of cost increase in industrial production. In addition, the method using a special polymer-type initiator has problems that the initiator is limited and the cost of the initiator is high.

  In the case of a graft polymer, since it can be easily synthesized by using a macromonomer, there are relatively few restrictions on production, but there is a problem of increased cost because the method for producing the macromonomer is special.

  Patent Document 1 discloses a block polymer using a monomer having two vinyl functional groups having different reactivities. This is because one highly reactive vinyl functional group is polymerized with a certain monomer in the first stage polymerization, and then the low reactive vinyl functional group is polymerized with another monomer in the second stage polymerization. It is a method to make it.

  However, in the method described in Patent Document 1, since any functional group is radically polymerizable, there is a problem that a vinyl functional group having low reactivity reacts in the first-stage polymerization. In addition, when a functional group that is too low in reactivity is used, it may not react even in the second stage polymerization. Furthermore, there are limitations on reaction conditions such as temperature, time, monomer species to be copolymerized and the like, and there is a problem that a block polymer cannot always be obtained easily.

  In order to solve the above problems, the present inventor has reported a block polymer bonded through a linking monomer having a radical polymerizable vinyl functional group and a non-radical polymerizable functional group in Patent Document 2. However, according to further studies by the present inventor, even the block polymer described in Patent Document 2 is more suitable for use in hair compositions such as a hair set agent composition and an aqueous composition for hair cosmetics. It is not easy to achieve superior performance in terms of performance, especially curl retention, flexibility, good fingering, stickiness, flaking, etc., especially curl retention The problem was that it was difficult to achieve good balance with the fingers.

JP 2002-534540 A JP 2008-189907 A

  The present invention solves the above-mentioned conventional problems and is a block polymer that can be produced industrially advantageously. For example, in a hair composition application such as a hair set agent composition or an aqueous composition for hair cosmetics, An object of the present invention is to provide a block polymer which is excellent in curl retention, flexibility, and good fingering, and in particular, has both curl retention and good fingering.

  As a result of earnest studies to solve the above problems, the present inventor is a block polymer bonded via a linking monomer having a radical polymerizable vinyl functional group and a non-radical polymerizable functional group, and has an acid value of It has been found that a block polymer in a specific range can be produced at a low cost by a simple process, and that an excellent cosmetic composition can be prepared using such a block polymer.

  The present invention has been achieved on the basis of such findings, and the gist thereof is as follows.

[1] A block polymer in which two or more blocks made of a monomer having a vinyl functional group are bonded via a linking monomer having a radical polymerizable vinyl functional group and a non-radical polymerizable functional group, The two or more blocks include at least a first block and a second block having different monomer compositions, and the block polymer has an acid value in the range of 200 mgKOH / g to 700 mgKOH / g.

[2] The block polymer according to [1], wherein the linking monomer is an oxazoline functional group-containing vinyl monomer represented by the following general formula (1).

(Wherein R ¹ represents a hydrogen atom or a methyl group, R ^{2 to} R ⁵ each independently represents a hydrogen atom, an alkyl group, an alkoxyalkyl group, an aryl group, an alkylaryl group, or an alkoxyaryl group; Represents any divalent linking group or direct bond.)

[3] The block polymer according to [1] or [2], wherein each of the first block and the second block has the following monomer composition.
(I) 1st block Linking monomer 0.1-20 wt%
Alkyl acrylate 1-99.9 wt%
Alkyl methacrylate 0-98wt%
Alkoxyalkyl (meth) acrylate 0-98wt%
(II) Second block 30% to 100% by weight of a vinyl monomer containing a carboxylic acid group
Hydrophilic vinyl monomer 0-70wt%
(However, hydrophilic vinyl monomers that do not contain carboxylic acid groups)
Hydrophobic vinyl monomer 0-70wt%

[4] The block polymer according to [3], wherein in the monomer composition of the first block, alkoxyalkyl (meth) acrylate is 1 to 98 wt%.

[5] A block polymer in which two or more blocks comprising a monomer having a vinyl functional group are bonded via a linking monomer having a radical polymerizable vinyl functional group and a non-radical polymerizable functional group, The two or more blocks include at least a first block and a second block each having a monomer composition different from each other, wherein the linking monomer is represented by the following general formula (1). A block polymer, which is a group-containing vinyl monomer and has an acid value in the range of 300 mgKOH / g to 450 mgKOH / g.
(I) 1st block Linking monomer 0.1-20 wt%
Alkyl acrylate 60-99.9 wt%
Alkyl methacrylate 0-98wt%
Methoxyethyl (meth) acrylate 1-39 wt%
(II) Second block Vinyl monomer containing carboxylic acid group 70 to 100 wt%
Hydrophilic vinyl monomer 0-30wt%
(However, hydrophilic vinyl monomers that do not contain carboxylic acid groups)
Hydrophobic vinyl monomer 0-30wt%

(Wherein R ¹ represents a hydrogen atom or a methyl group, R ^{2 to} R ⁵ each independently represents a hydrogen atom, an alkyl group, an alkoxyalkyl group, an aryl group, an alkylaryl group, or an alkoxyaryl group; Represents any divalent linking group or direct bond.)

  According to the present invention, even if the acid value is high, a uniform and low-viscosity solution is obtained, and, for example, in hair composition applications such as a hair set composition or a hair cosmetic aqueous composition, curl retention, flexibility It is possible to provide a block polymer that is excellent in performance and finger-feeling, and in particular has both curl retention and finger-handling. In addition, the block polymer of the present invention can be produced at a low cost by a simple process without requiring a special initiator and without using a macromonomer, and is suitable for industrial production.

Hereinafter, embodiments of the present invention will be described in detail.
In addition, in this specification, when mentioning curl retention, flexibility, good fingering, stickiness, lack of flaking, and the like, it means the evaluation described in the section of Examples.

[Block polymer of the present invention]
The block polymer of the present invention is a block polymer in which two or more blocks composed of a monomer having a vinyl functional group are bonded via a linking monomer having a radical polymerizable vinyl functional group and a non-radical polymerizable functional group. The two or more blocks include at least a first block and a second block having different monomer compositions, and have an acid value in the range of 200 mgKOH / g to 700 mgKOH / g.

  In the block polymer of the present invention, the linking monomer having a radical polymerizable vinyl functional group and a non-radical polymerizable functional group has at least one radical polymerizable vinyl functional group, and is a normal radical polymerization condition. However, it has a functional group (hereinafter referred to as a non-radically polymerizable functional group) capable of reacting and forming a covalent bond under other conditions.

  In the present invention, by using such a linking monomer, the radical polymerizable vinyl functional group radically polymerizes with another monomer having a vinyl functional group to form one block, while the non-radical A polymerizable functional group reacts with a monomer that forms another block to form a covalent bond, and a block polymer can be obtained very efficiently.

  The radical polymerizable vinyl functional group and the non-radical polymerizable functional group have completely different reaction mechanisms, so that the non-radical polymerizable functional group does not react during the reaction of the radical polymerizable vinyl functional group. Easy to control. Also, there are few restrictions on reaction conditions such as temperature, time, and monomer species to be copolymerized.

  The linking monomer only needs to have at least one of each group, and may have a plurality, but for ease of control of the molecular weight of the polymer, the linking monomer is composed of a radical polymerizable vinyl functional group and a non-radical polymerizable. Most preferred are those each having one functional group. The radical polymerizable vinyl functional group and the non-radical polymerizable functional group in the linking monomer may be linked by a covalent bond.

  At this time, the radical polymerizable vinyl functional group is copolymerized with a part of at least one block structure, and the non-radical polymerizable functional group reacts with a part of the functional group of at least one block structure and is covalently bonded. ing.

  Non-radical polymerizable functional groups include isocyanate groups, epoxy groups, hydroxyl groups, amine groups, carboxylic acid groups, acid anhydrides, thiosulfide groups, oxazoline groups, and the like. Oxazoline-based functional groups are particularly preferable because of their high reactivity, ease of handling, and limited reaction conditions.

The radical polymerizable vinyl functional group and the oxazoline functional group in the linking monomer may be linked by a covalent bond, and each of the radical polymerizable vinyl functional group and the oxazoline functional group has at least one. What is necessary is just to have two or more.
The oxazoline-based functional group here is a general term for those having an oxazoline ring structure including an oxazoline group having a substituent such as an alkyl group or an aryl group. In view of easy control of the molecular weight of the polymer, the linking monomer preferably has one of each group. Among these, from the viewpoint of high reactivity and ease of production or availability of raw materials, the connecting monomer is preferably represented by the following general formula (1).

(Wherein R ¹ represents a hydrogen atom or a methyl group, R ^{2 to} R ⁵ each independently represents a hydrogen atom, an alkyl group, an alkoxyalkyl group, an aryl group, an alkylaryl group, or an alkoxyaryl group; Represents any divalent linking group or direct bond.)

Here, R ¹ is preferably a hydrogen atom in order to increase the reactivity of the oxazoline-based functional group.

R ^{2 to} R ⁵ each independently represent a hydrogen atom, an alkyl group, an alkoxyalkyl group, an aryl group, an alkylaryl group, or an alkoxyaryl group, and the alkyl group portion and the alkoxy group in these groups are linear. But it may be branched. The aryl group in these groups is preferably a phenyl group.

More preferably, R ^{2 to} R ⁵ are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkyl group having 1 to 6 carbon atoms having an alkoxy group having 1 to 6 carbon atoms, or 1 to carbon atoms. 6 is a phenyl group optionally substituted by an alkyl group having 6 or an alkoxy group having 1 to 6 carbon atoms. More preferred are a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and an alkyl group having 1 to 6 carbon atoms having an alkoxy group having 1 to 6 carbon atoms. Among them, a hydrogen atom or a methyl group is preferred, and most preferred Is a hydrogen atom. This is to increase the reactivity of the oxazoline functional group.

  A is preferably a direct bond in order to increase the reactivity of the oxazoline functional group.

The linking monomer having the vinyl functional group and the oxazoline functional group represented by the general formula (1) (hereinafter, the monomer having the vinyl functional group is referred to as “vinyl monomer” and is suitable for the present invention). A linking monomer having a functional group and an oxazoline functional group may be referred to as an “oxazoline functional group-containing vinyl monomer”.) Although not particularly limited, for example,
2-vinyl-2-oxazoline,
2-vinyl-4-methyl-2-oxazoline,
2-vinyl-4-dimethyl-2-oxazoline,
2-vinyl-4-diethyl-2-oxazoline,
2-vinyl-4-methoxy-2-oxazoline,
2-vinyl-4-ethoxy-2-oxazoline,
2-vinyl-4-methoxymethyl-2-oxazoline,
2-vinyl-4-phenyl-2-oxazoline,
2-vinyl-5-methyl-2-oxazoline,
2-vinyl-5-ethyl-2-oxazoline,
2-vinyl-5-dimethyl-2-oxazoline,
2-vinyl-5-methoxy-2-oxazoline,
2-vinyl-5-ethoxy-2-oxazoline,
2-vinyl-5-methoxymethyl-2-oxazoline,
2-vinyl-5-phenyl-2-oxazoline,
2-vinyl-4-methoxymethyl-5-phenyl-2-oxazoline 2-isopropenyl-2-oxazoline,
2-isopropenyl-4-methyl-2-oxazoline,
2-isopropenyl-4-dimethyl-2-oxazoline,
2-isopropenyl-4-diethyl-2-oxazoline,
2-isopropenyl-4-methoxy-2-oxazoline,
2-isopropenyl-4-ethoxy-2-oxazoline,
2-isopropenyl-4-methoxymethyl-2-oxazoline,
2-isopropenyl-4-phenyl-2-oxazoline,
2-isopropenyl-5-methyl-2-oxazoline,
2-isopropenyl-5-ethyl-2-oxazoline,
2-isopropenyl-5-dimethyl-2-oxazoline,
2-isopropenyl-5-methoxy-2-oxazoline,
2-isopropenyl-5-ethoxy-2-oxazoline,
2-isopropenyl-5-methoxymethyl-2-oxazoline,
2-isopropenyl-5-phenyl-2-oxazoline,
And 2-isopropenyl-4-methoxymethyl-5-phenyl-2-oxazoline.

  Of these, 2-vinyl-2-oxazoline, 2-vinyl-4-dimethyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline are preferred because of their high reactivity and availability of raw materials. 2-isopropenyl-2-oxazoline, 2-isopropenyl-4-dimethyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, 2-vinyl-4-methoxymethyl-5-phenyl-2 -Oxazoline, more preferably 2-vinyl-2-oxazoline, 2-vinyl-4-dimethyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, most preferably 2-vinyl- 2-oxazoline.

  In forming the block structure, the covalent bond formed using the oxazoline-based functional group is not particularly limited, but is preferably one that has reacted with a carboxylic acid group or one that has reacted with an epoxy group. . The structure after the reaction is as shown below.

(Wherein, B and C are part of a block polymer, respectively, ^{R 6} has the same meaning as ^{R 1} in the general formula ^(1), the general formula R 7 ^{to R 10} are each independently (1) And is synonymous with R ^{2 to} R ⁵ in FIG.

Hereinafter, the block polymer of the present invention will be described.
The block polymer of the present invention comprises a monomer having a vinyl functional group, that is, two or more blocks composed of a vinyl monomer via a linking monomer having the above-mentioned radical polymerizable vinyl functional group and non-radical polymerizable functional group. The two or more blocks include at least a first block and a second block having monomer compositions different from each other.

  Of the first block and the second block included in the block polymer of the present invention, the first block is bonded to the radical polymerizable vinyl functional group of the linking monomer, and the second block is a non-radical polymerizable property of the linking monomer. When the linking monomer is included in the first block in combination with the functional group, the linking monomer amount relative to the total monomer amount constituting the first block (hereinafter referred to as “linking monomer ratio in the first block” may be referred to as Is preferably 0.1 to 20 wt%.

  When the proportion of the linked monomer in the first block is 0.1 wt% or more, the first block and the second block are easily linked with each other, which is efficient. The proportion of linked monomers in the first block is more preferably 0.2 wt% or more, and even more preferably 0.5 wt% or more. Further, when the proportion of the linked monomer in the first block is 20 wt% or less, the molecular weight is easily controlled, and gelation during polymerization tends to be difficult to handle. The proportion of linked monomers in the first block is more preferably 10 wt% or less, still more preferably 5 wt% or less, and particularly preferably 3 wt% or less.

  The second block preferably includes a monomer having a carboxylic acid group and / or an epoxy group and a vinyl functional group. By having a carboxylic acid group and / or an epoxy group in the second block, it is possible to form a covalent bond with an oxazoline functional group that is a non-radically polymerizable functional group, and by having a vinyl functional group It becomes possible to use for radical polymerization as a part of 2nd block.

  The monomer having a carboxylic acid group and / or an epoxy group and a vinyl functional group may have at least one of either a carboxylic acid group or an epoxy group, and may have a plurality. The vinyl functional group may have at least one, and may have a plurality. From the viewpoint of easy control of the molecular weight of the polymer, one vinyl functional group is preferable. Moreover, it is preferable to have only one kind of carboxylic acid group or epoxy group, and it is preferable to have only one carboxylic acid group or epoxy group.

  Although it does not specifically limit as a vinyl-type monomer containing the carboxylic acid group which comprises a 2nd block, For example, unsaturated carboxylic acid monomers, such as (meth) acrylic acid, maleic acid, itaconic acid, fumaric acid, crotonic acid, etc. Can be mentioned. Here, “(meth) acrylic acid” represents acrylic acid and / or methacrylic acid.

As the vinyl monomer containing a carboxylic acid group, (meth) acrylic acid or one represented by the following formula (6) is particularly preferable.
^{_{CH 2 = C (R 20)}} -COO- (CH 2) e -OCO-Y-COOH ··· (6)
(In the formula, R ²⁰ represents a hydrogen atom or a methyl group, e represents an integer of 1 to 4, and Y represents an optionally substituted phenyl group.)

  In the general formula (6), the substituent that the phenyl group of Y may have is preferably a linear or branched alkyl group having 1 to 4 carbon atoms, more preferably 1 to 1 carbon atoms. 3 linear or branched alkyl groups. Most preferably Y is a phenyl group having no substituent. A phenyl group having no substituent is preferable from the viewpoint of easy reaction.

  In the general formula (6), e is preferably an integer of 1 to 3, and most preferably 2. If it is e = 2, it is preferable at the point of the ease of reaction.

What is represented by General formula (6) will not be specifically limited if it is contained in this formula, For example, (meth) acrylic-acid ethyl terephthalate, (meth) acrylic-acid propyl terephthalate etc. are mentioned.
As the vinyl monomer containing a carboxylic acid group, (meth) acrylic acid is preferable because of its high reactivity and easy availability of raw materials.

In the present invention, a part or all of the carboxylic acid such as (meth) acrylic acid as the monomer component may be used in the form of a salt, and the salt may be formed before or after polymerization. Preferably after polymerization.
In the case of the salt form, hydrogen of the carboxylic acid is substituted with a part of the neutralizing agent, and examples thereof include a metal ion or an ammonium ion which may have a substituent. Examples of monovalent metal ions include alkali metal ions, such as sodium ions, potassium ions, and lithium ions.

Although an ammonium ion may have a substituent, Preferably it is a C1-C30 linear or branched alkyl group which may have a hydroxyl group as a substituent. For example, in addition to ammonium ions, quaternized products of primary to tertiary amines can be mentioned. Specifically, quaternized products of tertiary amines such as lauryldimethylamine, tetradecyldimethylamine, octadecyldimethylamine, and triethanolamine, and primary amines such as laurylamine, tetradecylamine, octadecylamine, and aminomethylpropanol. There are quaternized compounds.
Of these, quaternary ammonium ions are preferred.

  The neutralizing agent used for obtaining the salt as described above is not particularly limited. For example, metal hydroxide such as sodium hydroxide, potassium hydroxide, calcium hydroxide, ammonia water, laurylamine, trimethylamine, Preferable examples include amines such as lauryldimethylamine, monoethanolamine, diethanolamine, triethanolamine, aminomethylpropanol, aminomethylpropanediol, aminoethylpropanediol, N-methylglucamine, arginine, and lysine. These may be used alone or in combination of two or more. The neutralizing agent is more preferably sodium hydroxide or potassium hydroxide, monoethanolamine, diethanolamine, triethanolamine, or aminomethylpropanol.

  As a vinyl-type monomer containing the epoxy group which comprises a 2nd block, what is represented by following General formula (7) is preferable.

(Wherein R ²¹ represents a hydrogen atom or a methyl group, R ²² each independently represents a hydrogen atom or a methyl group, and n represents an integer of 0 to 20).

Here, R ²¹ is preferably a methyl group, and R ²² is preferably a hydrogen atom. N is preferably 0.

The vinyl monomer containing an epoxy group is not particularly limited as long as it is included in the above formula (7). For example, glycidyl (meth) acrylate, glycidyl (ethyleneoxy) ₂ (meth) acrylate, glycidyl (propylene) Oxy) ₂ (meth) acrylate, glycidyl (ethyleneoxy) ₂ (propyleneoxy) ₂ (meth) acrylate, glycidyl (ethyleneoxy) ₅ (propyleneoxy) ₂ (meth) acrylate, and the like. Here, “(meth) acrylate” represents acrylate and / or methacrylate.

  As the vinyl-based monomer containing an epoxy group, glycidyl (meth) acrylate is preferable and glycidyl methacrylate is most preferable because of easy reaction and availability of raw materials.

In addition, the vinyl-type monomer containing the carboxylic acid group and / or epoxy group of a 2nd block may be used individually by 1 type, or may use 2 or more types together.
The vinyl monomer containing a carboxylic acid group and / or an epoxy group constituting the second block is preferably a vinyl monomer containing a carboxylic acid group from the viewpoint that hydrophilicity can be imparted.

  When a linking monomer having a functional group other than the oxazoline functional group is used, it is preferable to have a vinyl monomer having a functional group highly reactive with it in the second block. Examples of the combination include an isocyanate group and a hydroxyl group and / or an amine group, an epoxy group and / or a thiosulfide group and a carboxylic acid group, and an acid anhydride and an amine group.

  In the block polymer of the present invention, the first block and the second block have different monomer compositions. The block polymer of the present invention has a different monomer composition, and therefore can exhibit more specific performance by having blocks having different properties.

The first block and the second block may be water-soluble, water-dispersible, or water-insoluble when evaluated independently.
Further, the block polymer of the present invention may be water-soluble, water-dispersible or water-insoluble.

When blending the block polymer of the present invention in a cosmetic composition, for example, a water-insoluble block polymer can be used by dissolving or dispersing in an oil component. If present, it can be used by dissolving and dispersing in water or lower alcohol.
Among them, the block polymer of the present invention is preferably soluble or dispersible in water and / or ethanol because it can be easily incorporated into a cosmetic composition.

In order to express specific performance, it is preferable that the first block and the second block constituting the block polymer of the present invention have significantly different properties, and in particular, either the first block or the second block. It is preferable that one is water-insoluble and the other is water-soluble or water-dispersible.
When the water solubility of the polymer changes depending on the pH, for example, when the block polymer of the present invention has a carboxylic acid group or an amino group, a part or all of it is neutralized with an alkaline substance or an acidic substance. When it is evaluated in the state, the solubility in water is judged. The degree of neutralization is determined by the degree of neutralization in a state as close as possible to the state in which the block polymer is used.

  Water-soluble or water-dispersible here (soluble or dispersible in water) means an effort to homogenize by heating or stirring when the polymer is dissolved in water at a concentration of 1% by weight. When the solution is allowed to stand at 25 ° C. for 24 hours, the polymer does not precipitate and the solution is homogeneous without phase separation. In particular, water-soluble means that a solution in which a polymer is dissolved is transparent, and the transmittance of a cell with an optical path length of 1 cm for light having a wavelength of 655 nm is 80% or more. The other state, that is, the state where the polymer precipitates or phase separates or the solution is non-uniform is called water insoluble.

  If either the first block or the second block is water-insoluble and the other is water-soluble or water-dispersible, the first block is water-insoluble and the second block is water-soluble for ease of production. Or it is preferable to set it as water dispersibility.

  Moreover, as for the 1st block and 2nd block which comprise the block polymer of this invention, it is preferable in the physical property that either one is a soft segment and the other is a hard segment. Thereby, for example, when the block polymer of the present invention is used as a hair setting agent, it is possible to obtain a flexible and high setting power.

  Here, the soft segment and the hard segment are indices determined by the softness of the polymer at room temperature, which is a normal use temperature, and are generally determined by the glass transition temperature (Tg). In the present invention, the Tg of each block calculated from the Tg of the homopolymer of each monomer is determined, and those having a Tg of −20 ° C. or lower are defined as soft segments, and those having higher Tg are defined as hard segments. If not, the block with a high value was set as a hard segment, and the block with a low value was set as a soft segment.

  When one of the physical properties of the first block and the second block is a soft segment and the other is a hard segment, the first block is a soft segment and the second block is a hard segment for ease of manufacturing. It is preferable to do.

  In this case, the Tg of the first block is preferably −100 to −20 ° C. More preferably, it is −50 to −20 ° C. Moreover, Tg of a 2nd block becomes like this. Preferably it is -20-150 degreeC, More preferably, it is -10-50 degreeC, Most preferably, it is -5-30 degreeC.

  In the block polymer of the present invention, it is particularly preferable that the first block is a water-insoluble and soft segment and the second block is a water-soluble or water-dispersible and hard segment because of ease of production.

  The water solubility and Tg of each block can be adjusted by appropriately selecting the type and amount of the vinyl monomer constituting each block. The preferred first block and second block configurations are obtained by polymerizing the following monomer compositions, respectively (the preferred monomer composition shown below may be referred to as “preferred monomer composition (1)”). .

<< Preferred monomer composition (1) >>
(I) 1st block Linking monomer 0.1-20 wt%
Hydrophilic vinyl monomer 0-79.9 wt%
Hydrophobic vinyl monomer 1-99.9 wt%
(II) Second block Vinyl monomer containing a carboxylic acid group and / or an epoxy group
0.1 to 100 wt%
Hydrophilic vinyl monomer 0-99.9wt%
(However, hydrophilic vinyl monomers that do not contain carboxylic acid groups and / or epoxy groups)
Hydrophobic vinyl monomer 0-90wt%

  The hydrophilic vinyl monomer here is usually a monomer having a solubility in distilled water at 20 ° C. (g / 100 g water) of greater than 1. The solubility is preferably 2 or more, more preferably 5 or more. The hydrophilic vinyl monomer is not particularly limited, and can be arbitrarily selected from, for example, an ionic monomer, a nonionic monomer, or a semipolar monomer.

  On the other hand, the hydrophobic vinyl monomer is a monomer having a solubility in distilled water at 20 ° C. (g / 100 g-water) of 1 or less. The solubility is preferably 0.1 or less, more preferably 0.01 or less. The hydrophobic vinyl monomer is not particularly limited, but is preferably a nonionic monomer.

The amount of linked monomers in the total amount of monomers constituting the first block is preferably 0.1 to 20 wt%.
As described above, when the proportion of the linking monomer in the first block is 0.1 wt% or more, the first block and the second block are easily and reliably connected, which is efficient. This ratio is more preferably 0.2 wt% or more, and still more preferably 0.5 wt% or more. Further, when the proportion of the linked monomer in the first block is 20 wt% or less, the molecular weight is easily controlled, and gelation during polymerization tends to be difficult to handle. This ratio is more preferably 10 wt% or less, further preferably 5 wt% or less, and particularly preferably 3 wt% or less.

  The hydrophilic vinyl monomer amount in the total monomer amount constituting the first block is preferably 0 to 79.9 wt%. This ratio is preferably 79.9 wt% or less because gas compatibility and flexibility are maintained. The amount of the hydrophilic vinyl monomer in the first block is more preferably 70 wt% or less, still more preferably 60 wt% or less, and most preferably 50 wt% or less. Further, the hydrophilic vinyl monomer may not be contained at all, but since the solubility in water or ethanol can be maintained by having an appropriate hydrophilic property, the hydrophilic vinyl monomer is more preferably 10 wt% or more, More preferably, it is 20 wt% or more, and most preferably 30 wt% or more.

  The amount of the hydrophobic vinyl monomer in the total amount of monomers constituting the first block is preferably 1 to 99.9 wt%. By setting this ratio to 1 wt% or more, gas compatibility, flexibility, lack of flaking, and the like are improved. The amount of the hydrophobic vinyl monomer in the first block is more preferably 30 wt% or more, and further preferably 40 wt% or more. In addition, when the amount of the hydrophobic vinyl monomer is 99.9 wt% or less, the connection with the second block by the connection monomer is easily performed. The amount of the hydrophobic vinyl monomer in the first block is more preferably 90 wt% or less, still more preferably 70 wt% or less, and most preferably 60 wt% or less.

  The amount of the vinyl monomer containing a carboxylic acid group and / or an epoxy group in the total monomer amount constituting the second block is preferably 0.1 to 100 wt%. By setting this ratio to 0.1 wt% or more, the connection with the first block by the connecting monomer is easily performed. The amount of the vinyl monomer containing a carboxylic acid group and / or an epoxy group in the second block is more preferably 5 wt% or more, further preferably 10 wt% or more, and most preferably 20 wt% or more. The total monomer of the second block may be a vinyl monomer containing a carboxylic acid group and / or an epoxy group, but more preferably 90 wt% from the viewpoint of affinity for hair and lack of flaking. Or less, more preferably 80 wt% or less, particularly preferably 50 wt% or less, and most preferably 40 wt% or less.

  The amount of the hydrophilic vinyl monomer not containing a carboxylic acid group and / or an epoxy group in the total monomer amount constituting the second block is preferably 0 to 99.9 wt%. By setting this ratio to 99.9 wt% or less, the hydrophilic block monomer containing no carboxylic acid group and / or epoxy group reacts with the linking monomer, so that the first block is sufficiently linked. . The amount of the hydrophilic vinyl monomer that does not contain a carboxylic acid group and / or an epoxy group in the second block is more preferably 80 wt% or less, further preferably 50 wt%, from the viewpoint of gas compatibility and flexibility. Or less, and most preferably 30 wt% or less.

  The amount of the hydrophobic vinyl monomer in the total amount of monomers constituting the second block is preferably 0 to 90 wt%. When this ratio is 90 wt% or less, moderate hydrophilicity can be imparted and the affinity for hair tends to increase. The amount of the hydrophobic vinyl monomer in the second block is more preferably 80 wt% or less. The second block may not contain any hydrophobic vinyl monomer, but from the viewpoint of gas compatibility and flexibility, the amount of the hydrophobic vinyl monomer is more preferably 10 wt% or more, and still more preferably. It is 30 wt% or more, and most preferably 50 wt% or more.

  What is suitable as a hydrophilic vinyl-type monomer contained in a 1st block and a 2nd block has a structure of following General formula (2) and / or (3).

_{^{CH 2 = C (R 11)}} -CO-NR 12 R 13 ··· (2)
(In the formula, R ¹¹ represents a hydrogen atom or a methyl group, and R ¹² and R ¹³ each independently represent a hydrogen atom, a linear or branched alkyl group having 1 to 3 carbon atoms, or a carbon number 1 having a hydroxyl group. Represents a linear or branched alkyl group of ˜3.)

^{_{CH 2 = C (R 14)}} -CO (O) - (CH 2) a - (CHOH) b -O-R 15
... (3)
(In the formula, R ¹⁴ represents a hydrogen atom or a methyl group, R ¹⁵ represents a hydrogen atom or a linear or branched alkyl group having 1 to 3 carbon atoms, a represents an integer of 1 to 4, and b represents 0. Or 1)

In General Formula (2), R ¹¹ is preferably a hydrogen atom, and R ¹² and R ¹³ are each independently a hydrogen atom or an alkyl group that may have a hydroxyl group having 1 to 3 carbon atoms. Examples of the alkyl group having 1 to 3 carbon atoms of R ¹² and R ¹³ include a methyl group, an ethyl group, a propyl group, and an isopropyl group. As a C1-C3 alkyl group which has a hydroxyl group, a hydroxymethyl group, 2-hydroxyethyl group, etc. are mentioned, for example. The sum of the carbon numbers of R ¹² and R ¹³ is preferably 2 or more and 4 or less, and most preferably 2.

In the general formula (3), R ¹⁴ is preferably a methyl group, R ¹⁵ is preferably an ethyl group, a is preferably an integer of 1 to 3, and most preferably 2. b is preferably 0.

  The vinyl monomer represented by the general formula (2) is not particularly limited as long as it is included in this formula. For example, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl Alkyl acrylamides such as (meth) acrylamide and N-isopropyl (meth) acrylamide; Dialkyl acrylamides such as N, N-dimethyl (meth) acrylamide and N, N-diethyl (meth) acrylamide; N-hydroxymethyl (meth) Hydroxyalkyl (meta) such as acrylamide, N- (2-hydroxyethyl) (meth) acrylamide, N, N-bis (hydroxymethyl) (meth) acrylamide, N, N-bis (2-hydroxyethyl) (meth) acrylamide ) Acrylamides; In "(meth) acrylic" means acrylic and methacrylic). Among these, N-methyl (meth) acrylamide, N-ethyl (meth) acrylamide, N-propyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N are preferable. -Diethyl (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, N- (2-hydroxyethyl) (meth) acrylamide.

  The vinyl monomer represented by the general formula (3) is not particularly limited as long as it is included in this formula. For example, hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 3-hydroxy Hydroxyalkyl (meth) acrylates such as propyl (meth) acrylate, 1,2-dihydroxypropyl (meth) acrylate, methoxymethyl (meth) acrylate, ethoxymethyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl ( Examples include alkoxyalkyl (meth) acrylates such as (meth) acrylate and butoxyethyl (meth) acrylate. Of these, 2-hydroxyethyl (meth) acrylate, 1,2-dihydroxypropyl (meth) acrylate, methoxyethyl (meth) acrylate, and ethoxyethyl (meth) acrylate are preferable.

  In addition, as hydrophilic vinyl monomers other than the monomers represented by the general formulas (2) and (3), short-chain alkyl acrylates such as methyl (meth) acrylate; methyl (meth) acrylamide, ethyl (meth) acrylamide, Short chain alkylamides such as propyl (meth) acrylamide; dimethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, dimethylaminoethyl (meth) acrylamide, dimethylaminopropyl (meth) acrylamide, trimethylammonioethyl ( (Meth) acrylate = chloride, trimethylammoniopropyl (meth) acrylate = chloride, trimethylammonioethyl (meth) acrylamide = chloride, trimethylammonioethyl (meth) acrylamide = Cationic acrylics such as Ride; Nonionic acrylics having a cyclic structure such as N-acryloylmorpholine and tetrahydrofurfuryl (meth) acrylate; ethyl carboxybetaine (meth) acrylate, (meth) acrylamidopropyl carboxybetaine, Acrylic compounds having a betaine structure such as (meth) acrylic acid ethylsulfobetaine and (meth) acrylamidopropylsulfobetaine; amine oxide structures such as (meth) acrylic acid ethyldimethylamine oxide and (meth) acrylamidopropyldimethylamine oxide Acrylics having the following can also be used.

  Moreover, what was illustrated as a monomer containing the carboxylic acid group and / or epoxy group which are contained in a 2nd block as a hydrophilic vinyl-type monomer of a 1st block can also be used.

  When used as a hair setting agent, it is included in the first block and the second block from the viewpoints of affinity for hair, solubility in water and / or ethanol, and compatibility with propellant. The hydrophilic vinyl monomer is preferably a hydrophilic vinyl monomer represented by the general formula (3), preferably hydroxyalkyl (meth) acrylates, alkoxyalkyl (meth) acrylates, more preferably 2-hydroxy. Ethyl (meth) acrylate, methoxyethyl (meth) acrylate, and ethoxymethyl (meth) acrylate.

  In addition, a hydrophilic vinyl monomer may be used individually by 1 type, may use 2 or more types together, and may use what is represented by General formula (2) or (3) together.

  A thing suitable as a hydrophobic vinyl-type monomer contained in a 1st block and a 2nd block has a structure of following General formula (4) and / or (5).

CH ₂ = C (R ¹⁶ ) —CO—O—R ¹⁷ (4)
(Wherein R ¹⁶ represents a hydrogen atom or a methyl group, and R ¹⁷ represents a linear, branched or cyclic alkyl group having 2 to 30 carbon atoms.)

^{_{CH 2 = C (R 18)}} -CO-NH-R 19 ··· (5)
(Wherein R ¹⁸ represents a hydrogen atom or a methyl group, and R ¹⁹ represents a linear, branched or cyclic alkyl group having 6 to 30 carbon atoms.)

In the general formulas (4) and (5), R ¹⁶ and R ¹⁸ are preferably methyl groups, and R ¹⁷ is preferably an alkyl group having 2 to 18 carbon atoms, more preferably an alkyl group having 4 to 18 carbon atoms. R ¹⁹ is preferably an alkyl group having 6 to 18 carbon atoms.

  The vinyl monomer represented by the general formula (4) is not particularly limited as long as it is included in this formula. For example, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, isobutyl Examples include (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, and the like. Of these, isobutyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, lauryl (meth) acrylate, and stearyl (meth) acrylate are preferable.

  The vinyl monomer represented by the general formula (5) is not particularly limited as long as it is included in this formula. For example, hexyl (meth) acrylamide, octyl (meth) acrylamide, 2-ethylhexyl (meth) acrylamide , Lauryl (meth) acrylamide, stearyl (meth) acrylamide and the like. Of these, octyl (meth) acrylamide, lauryl (meth) acrylamide, and stearyl (meth) acrylamide are preferable.

  Examples of the hydrophobic vinyl monomer other than the monomers represented by the general formulas (4) and (5) include benzyl (meth) acrylate, p-bromophenyl (meth) acrylate, and pt-butylphenyl (meth). Acrylic group-containing acrylics such as acrylate; Fluorine-containing acrylics such as trifluoroethyl (meth) acrylate and heptadecafluorodecyl (meth) acrylate; Silicone macromonomers such as polydimethylsiloxane alkyl (meth) acrylate; Can be used.

  When a block polymer is used for a hair setting agent, it has the following characteristics in terms of affinity for hair and solubility in water and / or ethanol, compatibility with a propellant, and flexibility during use. The hydrophobic vinyl monomer contained in the first block and the second block is preferably a hydrophobic vinyl monomer represented by the general formula (4).

  In addition, a hydrophobic vinyl type monomer may be used individually by 1 type, may use 2 or more types together, and may use what is represented by General formula (4) or (5) together.

  As for the weight average molecular weight of each block which comprises the block polymer of this invention, 1,000-500,000 are respectively preferable. By setting the weight average molecular weight of each block to 1,000 or more, the properties of each block are easily reflected in the entire block polymer, and the setting power and flexibility are improved in the use as a hair setting agent composition. More preferably, the weight average molecular weight is 3,000 or more, and more preferably 5,000 or more. By setting the weight average molecular weight to 500,000 or less, the handleability during production becomes easy. More preferably, the weight average molecular weight is 100,000 or less, more preferably 50,000, and most preferably 20,000 or less.

  The weight average molecular weight of the block polymer of the present invention is preferably 3,000 to 1,000,000. By setting the weight average molecular weight to 3,000 or more, the setting power is increased in the use as a hair setting agent composition. More preferably, it is 5,000 or more, More preferably, it is 10,000 or more. When the weight average molecular weight is 1,000,000 or less, the handleability during production becomes easy. More preferably, it is 500,000 or less, More preferably, it is 100,000, Most preferably, it is 50,000 or less.

  The weight ratio of the first block and the second block constituting the block polymer of the present invention is preferably in the range of 1/99 to 99/1. Thereby, the property of each block is easily reflected in the entire block polymer, and the setting power and flexibility are improved in the use as a hair setting agent composition. More preferably, the weight ratio is 1/50 to 50/1, more preferably 1/9 to 9/1, still more preferably 1/3 to 3/1, and most preferably 1/2 to 2. / 1.

The weight average molecular weight of the polymer can be measured by gel permeation chromatography (for example, using tetrahydrofuran as a developing solvent).
In the block polymer, when each block has extremely different properties, the solubility of the block is different, so that it may be difficult to accurately measure the molecular weight under a single condition.
Since it is known that the magnitude of the molecular weight is relatively correlated with the solution viscosity, in such a case, the solution viscosity may be evaluated instead of the molecular weight.

  The block polymer of the present invention preferably has a viscosity capable of preparing a 20 wt% ethanol solution at 25 ° C., more preferably the viscosity of the 20 wt% ethanol solution at 25 ° C. is 5,000 mPa · s or less, Preferably it is 1,000 mPa * s or less, Most preferably, it is 500 Pa * s or less. On the other hand, this viscosity is usually 10 mPa · s or more, preferably 30 mPa · s or more, more preferably 50 mPa · s or more.

  The molecular weight and viscosity of the polymer can be adjusted, for example, by controlling the degree of polymerization of the polymer in the method for producing a block polymer of the present invention described later. The molecular weight and viscosity can also be controlled by increasing or decreasing the addition amount of a crosslinking agent such as a polyfunctional acrylate. However, if the crosslinking agent is added too much, the molecular weight and the viscosity are rapidly increased. For industrial production, it is difficult to control the addition amount. For this reason, it is most preferable not to use a crosslinking agent.

  The block polymer of the present invention has an acid value of 200 to 700 mgKOH / g. When the block polymer of the present invention is used for a hair setting agent, etc., the acid value is 200 mgKOH / g or more, so that it is excellent in flexibility, non-stickiness, good fingering and the like. Further, when the acid value is 700 mgKOH / g or less, the curl retention characteristic due to moisture resistance and the like can be maintained. The acid value of the block polymer of the present invention is preferably 250 mgKOH / g or more, more preferably 270 mgKOH / g or more, further preferably 300 mgKOH / g or more, preferably 500 mgKOH / g or less, more preferably 450 mgKOH / g or less. .

The adjustment of the acid value of the block polymer of the present invention is, for example, (1) adjusting the content of the vinyl monomer having a carboxylic acid group in the second block (2) adjusting the ratio of the first block to the second block. (3) It can be carried out by adjusting the amount of the carboxylic acid group of the vinyl monomer having a carboxylic acid group.

  In the present invention, the acid value of the block polymer is either an actual value measured by the method described in the section of the below-mentioned example or a theoretical value calculated from the constituent monomers of the block polymer. However, the measured value is preferably included in the range defined by the present invention.

As described above, the block polymer of the present invention is a polymer having a relatively high acid value, but as shown in the Examples, it gives a uniform and low-viscosity solution. This is due to the following reason.
A block polymer with a narrow molecular weight distribution and a precise structure synthesized by living radical polymerization or the like forms a structure to some extent even in solution. Therefore, when a block polymer having a high acid value and having a hydrophobic block is synthesized, it is high in solution. Although the block polymer of the present invention may have viscosity, each block has a molecular weight distribution that is somewhat wide and has a branched structure instead of a straight chain. It is considered to be.
Moreover, it is possible to adjust to the physical property of a solution suitable for the composition and molecular weight, and a film physical property by adjusting the amount of connection monomers suitably.

<Preferred embodiment>
When the block polymer of the present invention is used in a hair set agent composition or an aqueous composition for hair cosmetics, the block polymer is excellent in curl retention, flexibility, and good finger feeling, and in particular, the curl retention and good finger feeling are compatible. As a more preferable configuration of the first block and the second block, each of the following monomer compositions is polymerized (the preferable monomer composition shown below may be referred to as “preferred monomer composition (2)”). is there).

<< Preferred monomer composition (2) >>
(I) 1st block Linking monomer 0.1-20 wt%
Alkyl acrylate 1-99.9 wt%
Alkyl methacrylate 0-98wt%
Alkoxyalkyl (meth) acrylate 0-98wt%
(II) Second block 30% to 100% by weight of a vinyl monomer containing a carboxylic acid group
Hydrophilic vinyl monomer 0-70wt%
(However, hydrophilic vinyl monomers that do not contain carboxylic acid groups)
Hydrophobic vinyl monomer 0-70wt%

  In particular, when the block polymer of the present invention is used in a hair setting agent composition or an aqueous composition for hair cosmetics, it is excellent in curl retention, flexibility, and good finger feeling. More preferable configurations of the first block and the second block as the block polymer are configurations obtained by polymerizing the following monomer compositions, respectively (the preferable monomer composition shown below is referred to as “preferred monomer composition (3)”. In some cases, the connecting monomer is an oxazoline-based functional group-containing vinyl monomer represented by the general formula (1). An acid value of 450 mg KOH / g can be obtained.

<< Preferred monomer composition (3) >>
(I) 1st block Linking monomer 0.1-20 wt%
Alkyl acrylate 60-99.9 wt%
Alkyl methacrylate 0-98wt%
Methoxyethyl (meth) acrylate 1-39 wt%
(II) Second block Vinyl monomer containing carboxylic acid group 70 to 100 wt%
Hydrophilic vinyl monomer 0-30wt%
(However, hydrophilic vinyl monomers that do not contain carboxylic acid groups)
Hydrophobic vinyl monomer 0-30wt%

In the preferred monomer compositions (2) and (3), the amount of connected monomers in the total amount of monomers constituting the first block is 0.1 to 20 wt%. As described above, when the proportion of the linking monomer in the first block is 0.1 wt% or more, the first block and the second block are easily and reliably connected, which is efficient. This ratio is more preferably 0.2 wt% or more, and still more preferably 0.5 wt% or more. Further, when the proportion of the linked monomer in the first block is 20 wt% or less, the molecular weight is easily controlled, and gelation during polymerization tends to be difficult to handle. This ratio is more preferably 10 wt% or less, further preferably 5 wt% or less, and particularly preferably 3 wt% or less.
As the linking monomer, an oxazoline functional group-containing vinyl monomer represented by the general formula (1) is preferable.

The amount of alkyl acrylate in the total amount of monomers constituting the first block is preferably 1 to 99.9 wt%. By making this ratio 1 wt% or more, it is preferable because hydrophobicity and Tg can be kept low, and curl retention, flexibility and flaking can be improved. The amount of alkyl acrylate in the first block is more preferably 20 wt% or more, and still more preferably 60 wt% or more in order to further improve the flexibility. In addition, it is preferable that the alkyl acrylate amount is 99.9 wt% or less because the linking monomer can be easily linked to the second block, and the first block and the first block can be copolymerized with other monomers. The compatibility with the two blocks is improved, which may contribute to the stability of the solution and the uniformity of the film, which may be preferable. The ratio of alkyl acrylate is more preferably 98 wt% or less, and still more preferably 90 wt% or less.
As this alkyl acrylate, in the general formula (4), an alkyl acrylate represented by R ¹⁶ being a hydrogen atom, for example, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, Examples include t-butyl acrylate, hexyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, lauryl acrylate, stearyl acrylate, and methyl acrylate. Among these, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, lauryl acrylate, stearyl acrylate are more preferable, and n-propyl acrylate, isopropyl acrylate, n -Butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate.
Alkyl acrylate may be used individually by 1 type, or may use 2 or more types together.

The amount of alkyl methacrylate in the total amount of monomers constituting the first block is preferably 0 to 98 wt%. By making this ratio 98 wt% or less, Tg can be kept low, and flexibility and lack of flaking can be maintained. The amount of alkyl methacrylate in the first block is more preferably 60 wt% or less, and still more preferably 30 wt% or less. Alkyl methacrylate may not be contained in the first block at all, but by including alkyl methacrylate, moisture resistance can be improved and curl retention can be improved. In that case, the amount of alkyl methacrylate in the first block is more preferably 5 wt% or more, and still more preferably 10 wt% or more.
Examples of the alkyl methacrylate include alkyl methacrylates represented by R ¹⁶ as a methyl group in the general formula (4), such as ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, Examples include t-butyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, stearyl methacrylate, and methyl methacrylate. Among these, n-butyl methacrylate, isobutyl methacrylate, t-butyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, lauryl methacrylate, and stearyl methacrylate are preferable.
Alkyl methacrylate may be used individually by 1 type, or may use 2 or more types together.

  The total content of alkyl acrylate and alkyl methacrylate in the first block is preferably 30 wt% or more, more preferably 70 wt% or more, preferably 99 wt% or less, more preferably 95 wt% or less.

The amount of alkoxyalkyl (meth) acrylate in the total amount of monomers constituting the first block is preferably 0 to 98 wt%. By making this ratio 98 wt% or less, hydrophobicity can be maintained and curl retention and the like can be improved. The amount of alkoxyalkyl (meth) acrylate in the first block is preferably 70 wt% or less, more preferably 39 wt% or less. The first block may not contain any alkoxyalkyl (meth) acrylate, but alkoxyalkyl (meth) acrylate such as methoxyethyl (meth) acrylate and ethoxymethyl (meth) acrylate, preferably methoxyethyl (meth) By including the acrylate, the smoothness of the hair ends is improved in the use as a composition for hair, which is preferable. In this case, the amount of alkoxyalkyl (meth) acrylate such as methoxyethyl (meth) acrylate in the first block is more preferably 1 wt% or more, and further preferably 5 wt% or more.
Moreover, it is preferable to use an alkoxyalkyl acrylate because it is excellent in copolymerizability with the alkyl acrylate. Moreover, since the smoothness of a hair tip improves further, it is preferable.
As the alkoxyalkyl (meth) acrylate, alkoxyalkyl (meth) acrylate represented by the general formula (3), for example, methoxymethyl (meth) acrylate, ethoxymethyl (meth) acrylate, methoxyethyl (meth) acrylate, Examples include ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, and the like. Of these, methoxyethyl (meth) acrylate and ethoxyethyl (meth) acrylate are preferable, methoxyethyl (meth) acrylate is particularly preferable, and methoxyethyl acrylate is particularly preferable.
An alkoxyalkyl (meth) acrylate may be used individually by 1 type, or may use 2 or more types together.

  In the preferred monomer compositions (2) and (3), the amount of the vinyl monomer containing a carboxylic acid group in the total amount of monomers constituting the second block is preferably 30 to 100 wt%. By making this ratio 30 wt% or more, the linkage with the first block by the linking monomer is sufficiently facilitated. This ratio is more preferably 50 wt% or more, and still more preferably 70 wt% or more.

  Moreover, it is preferable that the vinyl-type monomer containing the carboxylic acid group which comprises a 2nd block is more than the connection monomer which comprises a 1st block. At this time, a part of the vinyl monomer containing the carboxylic acid group constituting the second block contributes to the reaction with the linking monomer, but the surplus part works as a hydrophilic monomer.

  The amount of the hydrophilic vinyl monomer not containing a carboxylic acid group in the total amount of monomers constituting the second block is preferably 0 to 70 wt%, particularly preferably 0 to 30 wt%. By making the amount of the hydrophilic vinyl monomer not containing a carboxylic acid group in the second block 70 wt% or less, the hydrophilic vinyl monomer containing a carboxylic acid group reacts with the linking monomer, and the first block and Are easily connected. The amount of the hydrophilic vinyl monomer that does not contain a carboxylic acid group in the second block is more preferably 50 wt% or less, more preferably 30 wt% or less, and most preferably 20 wt% or less from the viewpoint of flexibility and the like. It is. The hydrophilic vinyl monomer that does not contain a carboxylic acid group may not be contained in the second block. However, if the amount of the vinyl monomer that contains a carboxylic acid group in the second block is small, Use of a hydrophilic vinyl monomer that does not contain an acid group is preferred because water solubility is imparted. In this case, this ratio is more preferably 5 wt% or more, and further preferably 10 wt% or more.

  The amount of the hydrophobic vinyl monomer in the total amount of monomers constituting the second block is preferably 0 to 70 wt%, particularly preferably 0 to 30 wt%. By setting this ratio to 70 wt% or less, moderate hydrophilicity can be imparted, and the affinity for hair tends to increase. The amount of the hydrophobic vinyl monomer in the second block is more preferably 40 wt% or less, further preferably 30 wt% or less, and most preferably 20 wt% or less. The second block may not contain any hydrophobic vinyl monomer, but from the viewpoint of flexibility, the amount of the hydrophobic vinyl monomer is more preferably 1 wt% or more, and further preferably 3 wt% or more. Yes, most preferably 5 wt% or more.

  In addition, as the hydrophilic vinyl monomer not containing a carboxylic acid group contained in the second block in the above preferred monomer compositions (2) and (3), and the hydrophobic vinyl monomer, the aforementioned preferred monomer composition (1) One or two or more of those exemplified as the hydrophilic vinyl monomer and the hydrophobic vinyl monomer in can be used, and the same applies to suitable vinyl monomers.

[Method for producing block polymer of the present invention]
The block polymer of the present invention can be produced, for example, by mixing monomers that give respective structural units or precursors thereof, and performing solution polymerization, suspension polymerization, emulsion polymerization, or the like.
Moreover, about a raw material monomer, when superposing | polymerizing, a precursor can be used and can also be changed into a desired form by neutralization reaction, addition reaction, etc. after superposition | polymerization. These can be appropriately selected depending on the ease of synthesis.

The polymerization reaction is preferably performed in a hydrophilic solvent.
Examples of the hydrophilic solvent include ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, alcohol solvents such as methanol, ethanol, n-propanol, i-propanol, n-butanol, i-butanol, and sec-butanol, water, and the like. Is mentioned. These may be used alone or in combination of two or more. Among these, it is preferable to use an alcohol solvent.

As polymerization initiators, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), 2,2′-azobis (4-methoxy-2,4-dimethyl) Valeronitrile), dimethyl-2,2′-azobisisobutyrate, 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (1-cyclohexanecarbonitrile), 2,2 ′ -Azo compounds such as azobis (2-methyl-N- (2-hydroxyethyl) -propionamide), 2,2'-azobis (2-amidinopropane) dihydrochloride, benzoyl peroxide, dicumyl peroxide, di It can be used without particular limitation, such as peroxides such as -t-butyl peroxide and lauroyl peroxide, persulfates, or redox systems thereof. These may be used alone or in combination of two or more.
The polymerization initiator is preferably used in the range of 0.01 to 5% by mass with respect to all monomers.

  The polymerization reaction can be performed, for example, under an inert gas atmosphere such as nitrogen or argon, preferably at 30 to 120 ° C., more preferably at 40 to 100 ° C., usually for 1 to 30 hours. After completion of the polymerization, the produced polymer may be isolated from the reaction solution by an appropriate means such as solvent distillation or addition of a poor solvent. This polymer can be used as it is or after further purification, for example, in the production of cosmetics. Purification can be performed by combining appropriate means such as reprecipitation, solvent washing, and membrane separation as required.

  Below, the first block and the second block, which are composed of monomers having a vinyl functional group and have different monomer compositions, are connected via a linking monomer having a radical polymerizable vinyl functional group and a non-radical polymerizable functional group. A preferred method for producing the block polymer of the present invention which is bonded will be described by illustrating the following <Method 1> and <Method 2>.

<Method 1>
After the step of obtaining a first block by radical polymerization of the first block constituting vinyl monomer containing a linking monomer, a functional group capable of reacting with the non-radical polymerizable functional group is added to the non-radically polymerizable functional group of the linking monomer. A block polymer is obtained by performing a step (addition step) of adding the vinyl-based monomer possessed and a step of obtaining a second block by radical polymerization of the second block-constituting vinyl-based monomer (second block polymerization step). At that time, either the addition step or the second block polymerization step may be performed first or simultaneously.

For example, first, a linking monomer having a radical polymerizable vinyl functional group and an oxazoline functional group is used to form a first block containing the linking monomer. Next, a monomer having a carboxylic acid group and a vinyl functional group is added to react the oxazoline functional group with the carboxylic acid group. Furthermore, a block polymer can be obtained by adding and polymerizing another monomer constituting the second block.
Alternatively, the second block is separately formed by polymerizing other monomers constituting the second block including the monomer having a carboxylic acid group and a vinyl functional group, and the first block oxazoline functional group and the second block are formed. These carboxylic acid groups may be reacted to form a block polymer.
Furthermore, after the first block is formed, a block polymer can be obtained by adding another monomer constituting the second block including a monomer having a carboxylic acid group and a vinyl-based functional group, and simultaneously polymerizing and reacting. . According to this method, the block polymer can be obtained most simply.

<Method 2>
After the step of obtaining a second block by radical polymerization of a vinyl monomer containing a vinyl monomer having a functional group capable of reacting with a non-radically polymerizable functional group, the linking monomer is added to the functional group. A block polymer is obtained by performing the step (addition step) and the step of obtaining a first block by radical polymerization of the first block constituent vinyl monomer (first block polymerization step). At that time, either the addition step or the first block polymerization step may be performed first or simultaneously.

For example, first, the other block constituting the second block including the monomer having a vinyl functional group having a carboxylic acid group is polymerized in advance to form the second block. Next, a linking monomer having an oxazoline functional group and a radical polymerizable vinyl functional group is added to react the oxazoline functional group with a carboxylic acid group. Furthermore, a block polymer can be obtained by adding and polymerizing another monomer constituting the first block.
Alternatively, the first block is separately formed by polymerizing other monomers constituting the first block including the linking monomer, and the carboxylic acid group of the second block and the oxazoline-based functional group of the first block are reacted, It may be a block polymer.
Furthermore, a block polymer can be obtained by adding a first block constituent monomer including a linking monomer after the second block is formed and simultaneously polymerizing and reacting. According to this method, the block polymer can be obtained most simply.

  When the method 1 and the method 2 are compared, the method 1 is preferable because of high reactivity and easy reaction.

[Use of block polymer of the present invention and cosmetic composition]
The block polymer of the present invention is useful as a surface treatment agent such as an antistatic agent and a hard coat agent, and as a thickener or dispersant for paints, cosmetics, agricultural chemicals, pharmaceuticals, and the like.

<Cosmetic composition>
In a cosmetic composition, it is preferable to contain 0.01-50 wt% of block polymers of this invention. In order to make the effect of blending the polymer in the cosmetic composition sufficient, the content of the block polymer of the present invention is preferably 0.01 wt% or more. The block polymer content is more preferably 0.1 wt% or more, and still more preferably 0.3 wt% or more. From the viewpoint of moderate viscosity and easy handling and cost, the block polymer content is preferably 50 wt% or less, more preferably 20 wt% or less, still more preferably 10 wt% or less, and most preferably 5 wt%. % Or less.

<Hair hair set composition>
The block polymer of the present invention can be suitably used for a hair set composition among cosmetic compositions, and preferred blending compositions in this case are as follows.
0.1-20 wt% of block polymer of the present invention
0 ~ 99wt% of water
Ethanol 0-99wt%
LPG or / and DME 0-70 wt%
(However, the total amount of water, ethanol, LPG and / or DME is 49.9 to 99.9 wt%)
Additive 0-50wt%

  In the hair setting agent composition of the present invention, the block polymer of the present invention preferably contains 0.1 to 20 wt%. That is, in order to make the setting force sufficient, the block polymer content is preferably 0.1 wt% or more, more preferably 1 wt% or more, and further preferably 2 wt% or more. Further, the block polymer content is preferably 20 wt% or less, more preferably 10 wt% or less, and further preferably 5 wt% or less from the viewpoint of moderate viscosity and easy handling and cost.

The amount of water and ethanol, LPG (liquefied petroleum gas) or / and DME (dimethyl ether) effective to dissolve the polymer is generally preferably in the range of 49.9 to 99.9 wt%. . In order to make the set force sufficient, the content of these solvents is preferably 99.9 wt% or less, and is preferably 49.9 wt% or more from the viewpoint of moderate viscosity and easy handling and cost.
Preferably, the ethanol content ranges from 0 to 99 wt%, the water content ranges from 0 to 99 wt%, and the LPG or / and DME content ranges from 0 to 70 wt%. These ratios are appropriately selected depending on the product form. Can do.

  For so-called sprays using a volatile gas as a propellant, the water content is preferably 5 wt% or less, more preferably 3% or less, and most preferably 1% or less. In that case, the content of ethanol is preferably 20 to 80 wt%, more preferably 30 to 70 wt%, and most preferably 40 to 60 wt%. In that case, since the content of LPG or / and DME works as a propellant in addition to dissolving the polymer, it is preferably 10 to 70 wt%, more preferably 30 to 60 wt%, most preferably 40 to 60 wt%. is there.

  In addition, LPG here is liquefied petroleum gas which has butane, propane, etc. as a main component. The composition of LPG is not particularly limited, but propane and butane are preferably 80 wt% or more, more preferably 90 wt% or more of the whole. The weight ratio of propane and butane is preferably 9: 1 to 1: 9, more preferably 9: 1 to 5: 5, and still more preferably 8: 2 to 6: 4. As butane, n-butane or iso-butane can be used.

  Carbon dioxide or the like can also be used as another propellant not included in the above composition.

  When used as a hair setting agent, additives can be blended within a range that does not significantly impair the performance, and the content is preferably 0 to 50 wt%. In order to impart the performance of the active ingredient and not hinder the performance, the content of other additives is preferably 0.1 to 30 wt%, more preferably 0.5 to 10 wt%, most preferably 0. 0.5 to 5 wt%.

  Preferably, the hair set agent composition includes a composition containing 0.1 to 10 wt% of silicones as one of the additives. In order to give gloss to hair and improve combing, the hair set composition preferably contains 0.1 wt% or more of silicones, more preferably 0.2 wt% or more, and still more preferably 0.8%. It is 3 wt% or more, and most preferably 0.5 wt% or more. Further, from the viewpoint of moderate viscosity and easy handling and cost, the silicone content is preferably 10 wt% or less, more preferably 5 wt% or less, and further preferably 2 wt% or less.

  Here, the silicones refer to polymers having a structure in which silicon (organosilicon) to which organic groups are bonded and oxygen are alternately linked by chemical bonds. These may further have a substituent.

  Examples of silicones include, but are not limited to, polydimethylsiloxane, polydimethylsiloxane alkylene oxide copolymer, amino-modified polydimethylsiloxane, polyether-modified polydimethylsiloxane, methylphenylpolysiloxane, epoxy-modified polydimethylsiloxane, fluorine Examples include modified polydimethylsiloxane, alcohol-modified polydimethylsiloxane, alkyl-modified polydimethylsiloxane, alkoxy-modified polydimethylsiloxane, and cyclic silicone. These are described in JP-A-2000-336018.

  Examples of polydimethylsiloxane include “KF96H-1 million” (Shin-Etsu Chemical Co., Ltd.), “SH200”, “BY11-007”, “BY22-029” (all are Toray Dow Corning Silicone Co., Ltd.), “TSF451. "(Toshiba Silicone Co., Ltd.)" and "L-45" (Nihon Unicar Co., Ltd.).

  As a polydimethylsiloxane alkylene oxide copolymer, what is marketed as "F-178-21" (Nihon Unicar Co., Ltd.) is mentioned.

  Examples of the amino-modified polydimethylsiloxane include those having an aminoalkyl group such as an aminoethyl group and an aminopropyl group, and may have a substituent such as an alkyl group or a hydroxyl group. The alkyl group for the substituent is preferably a linear or branched alkyl group having 1 to 12 carbon atoms.

  These amino-modified polydimethylsiloxanes are obtained by copolymerizing dimethylsiloxane and the above siloxane having an aminoalkyl group, or by post-modifying polydimethylsiloxane with a compound having an aminoalkyl group as described above to form a polydimethylsiloxane skeleton. It is obtained by introducing an aminoalkyl group.

  Commercially available products of amino-modified polydimethylsiloxane include, for example, “USAR SILICONE ALE56” (Union Carbide), “ABIL9905” (The Goldschmidt AG), “KF857”, “KF867”, “KF865” (all And Shin-Etsu Chemical Co., Ltd.), “SM8702C” (Toray Dow Corning Silicone Co., Ltd.), “FZ-3707” (Nihon Unicar Co., Ltd.), and the like.

  Examples of the polyether-modified polydimethylsiloxane include those having a monomer skeleton such as oxyethylene, oxypropylene, oxybutylene, oxypentamethylene, oxyhexamethylene, oxy (2,2-dimethyl) propylene, and polyoxyethylene And those having an oxyalkylene group of a homopolymer skeleton such as polyoxypropylene, polyoxybutylene, polyoxypentamethylene, polyoxyhexamethylene, or a copolymer skeleton such as a poly (oxyethyleneoxypropylene) copolymer. It is done. These may have a substituent such as a hydroxyl group or an alkyl group. The alkyl group for the substituent is preferably a linear or branched alkyl group having 1 to 12 carbon atoms. Particularly preferred are those having an oxyalkylene group of the polymer skeleton.

  Examples of a method for producing such a modified polydimethylsiloxane having an oxyalkylene group include a method of copolymerizing dimethylsiloxane and a siloxane having an oxyalkylene group, There is a method of post-modifying and introducing an oxyalkylene group into the polydimethylsiloxane skeleton.

  Most preferably, the polyether-modified polydimethylsiloxane is obtained by copolymerizing dimethylsiloxane and siloxane having an oxyalkylene group in the polymer skeleton.

  Commercially available products of polyether-modified polydimethylsiloxane include, for example, “KF945A”, “KF351A”, “KF354A” (Shin-Etsu Chemical Co., Ltd.), “SH3771C”, “SH3749” (Toray Dow Corning Silicone Co., Ltd.) , “L-7602C”, “L-720” (Nihon Unicar Co., Ltd.), “SF1066” (General Electric Company), and the like.

  As methylphenylpolysiloxane, “KF56” (Shin-Etsu Chemical Co., Ltd.), “SH556” (Toray Dow Corning Silicone Co., Ltd.), “FZ-209” (Nihon Unicar Co., Ltd.) and the like are commercially available.

  As the epoxy-modified polydimethylsiloxane, “X-60-164” (Shin-Etsu Chemical Co., Ltd.), “PS922” (Chisso Corporation), “L-9300” (Nihon Unicar Corporation) and the like are commercially available.

  As the fluorine-modified polydimethylsiloxane, “X-22-820” (Shin-Etsu Chemical Co., Ltd.), “PS182” (Chisso Corporation) and the like are commercially available.

  As alcohol-modified polydimethylsiloxane, “KF851” (Shin-Etsu Chemical Co., Ltd.), “FM4411” (Chisso Corporation), “FZ-3722”, “F-235-21” (Nihon Unicar Corporation), etc. are commercially available. Has been.

  As the alkyl-modified polydimethylsiloxane, “KF410”, “KF-413” (Shin-Etsu Chemical Co., Ltd.), “PS130”, “PS137” (Chisso Corporation) and the like are commercially available.

  As the alkoxy-modified polydimethylsiloxane, “PS912” (Chisso Corporation), “FZ-3701” (Nihon Unicar Corporation) and the like are commercially available.

  As the cyclic silicone, “SH244”, “SH245”, “SH246” (Toray Dow Corning Silicone) are commercially available.

  These silicones may be used alone or in combination of two or more.

  Other additives that can be incorporated into the hair set composition of the present invention include anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, semipolar surfactants, higher alcohols, water-soluble Include a cationic polymer, a cationic polymer, an anionic polymer, a nonionic polymer, an amphoteric polymer, an oil component, a pearling agent, and a suspending agent.

  Although the component which may be mix | blended is illustrated below, it is not limited to these.

  Examples of the anionic surfactant include α-olefin sulfonate, higher alcohol sulfate, polyoxyethylene alkyl ether sulfate, paraffin sulfonate, polyoxyethylene alkyl ether carboxylate, alkyl sulfosuccinate. , N-acyl-β-alanine salts, N-acyl glutamate salts, acylmethyl taurine salts, and the like commonly used in detergent compositions can be used. Examples of counter ions of these anionic surfactants include sodium, potassium, ammonium, triethanolamine, diethanolamine and the like. An anionic surfactant may be used individually by 1 type, and may use 2 or more types together.

  As the cationic surfactant, for example, a long-chain alkyl group-containing quaternary ammonium salt is preferable. The long chain alkyl group is preferably one having 6 to 24 carbon atoms. Long chain alkyl group-containing quaternary ammonium salts include, for example, long chains such as cetyl trimethyl ammonium salt, stearyl trimethyl ammonium salt, behenyl trimethyl ammonium salt, cetyl dimethyl benzyl ammonium salt, stearyl dimethyl benzyl ammonium salt, and behenyl dimethyl benzyl ammonium salt. Two long chains such as one, dicetyldimethylammonium salt, distearyltrimethylammonium salt, dibehenyltrimethylammonium salt, dicetylmethylbenzylammonium salt, distearylmethylbenzylammonium salt, dibehenylmethylbenzylammonium salt And three long chains such as tricetylmethylammonium salt, tristearylmethylammonium salt, and tribehenylmethylammonium salt. And the like of it. Among them, one having one or two long chains is preferable, and one having one long chain is more preferable. These may be used alone or in combination of two or more.

  Examples of amphoteric surfactants include those containing a betaine group and a long-chain alkyl group such as aminoacetic acid betaine, imidazolium betaine, sulfobetaine, and amidopropyl betaine. These may be used alone or in combination of two or more.

  Examples of nonionic surfactants include polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, fatty acid monoethanolamide, and fatty acid diethanolamide. These may be used alone or in combination of two or more.

  Examples of the semipolar surfactant include lauramine oxide (lauryl dimethylamine oxide). Such surfactants are generally commercially available and can be used as they are. These may be used alone or in combination of two or more.

  Examples of the water-soluble polymer include methyl cellulose and hydroxymethyl cellulose. These may be used alone or in combination of two or more.

  The higher alcohol is not particularly limited as long as it is a compound having a long-chain alkyl group and a hydroxyl group, but an alkyl group having 6 to 24 carbon atoms and a linear or branched alkyl group is preferable. The higher alcohol may have two or more hydroxyl groups, but preferably has only one hydroxyl group, and examples thereof include octyl alcohol, cetyl alcohol, stearyl alcohol, and behenyl alcohol. Of these, cetyl alcohol, stearyl alcohol, and behenyl alcohol are preferable. These may be used alone or in combination of two or more.

  Examples of the cationic polymer include a cation-modified cellulose ether derivative, polydimethyldiallylammonium halide, a copolymer of dimethyldiallylammonium halide and acrylamide, and the like. These may be used alone or in combination of two or more.

  Examples of the anionic polymer include acrylic acid derivatives (polyacrylic acid and salts thereof, acrylic acid-acrylamide-ethyl acrylate copolymer and salts thereof), methacrylic acid derivatives, crotonic acid derivatives, and the like. These may be used alone or in combination of two or more.

  Examples of nonionic polymers include acrylic acid derivatives (hydroxyethyl acrylate-methoxyethyl acrylate copolymer, polyacrylamide, etc.) and vinylpyrrolidone derivatives (polyvinylpyrrolidone, vinylpyrrolidone-vinyl acetate copolymer, etc.). It is done. These may be used alone or in combination of two or more.

  Examples of the amphoteric polymer include dimethyldiallylammonium chloride derivatives (acrylamide-acrylic acid-dimethyldiallylammonium chloride copolymer, acrylic acid-dimethyldiallylammonium chloride copolymer, etc.) and the like. These may be used alone or in combination of two or more.

  Examples of the oil include olive oil, jojoba oil, liquid paraffin, and fatty acid alkyl ester oil. These may be used alone or in combination of two or more.

  Examples of the pearling agent include fatty acid ethylene glycol such as ethylene glycol distearate. These may be used alone or in combination of two or more.

  Examples of the suspending agent include polystyrene emulsions. These may be used alone or in combination of two or more.

  Other ingredients include natural extracts of animals and plants and derivatives thereof, organic acids such as citric acid and lactic acid, inorganic salts such as sodium chloride, solubilizers (ethanol, ethylene glycol, propylene glycol, etc.), moisturizers (glycerin, sorbitol, Maltitol, dipropylene glycol, 1,3-butylene glycol, hyaluronic acid, etc.), antioxidants, UV absorbers, bactericides, preservatives, chelating agents, fragrances, colorants, higher fatty acids, thickeners, metal sequestering 1 type (s) or 2 or more types, such as an agent (edetate etc.), a pH adjuster, a foaming enhancer, etc. can be mix | blended suitably in the range which does not impair the effect of this invention.

<Aqueous composition for hair cosmetics>
The block polymer of the present invention can also be suitably used for an aqueous composition for hair cosmetics. In this case, the preferred composition is as follows.
0.1-20 wt% of block polymer of the present invention
Water 40-99wt%
Ethanol 0-40wt%
Additive 0-50wt%

  In the aqueous composition for hair cosmetics of the present invention, the block polymer of the present invention preferably contains 0.1 to 20 wt%. That is, in order to make the setting force sufficient, the block polymer content is preferably 0.1 wt% or more, more preferably 1 wt% or more, and further preferably 2 wt% or more. Further, the block polymer content is preferably 20 wt% or less, more preferably 10 wt% or less, and further preferably 5 wt% or less from the viewpoint of moderate viscosity and easy handling and cost.

  The amount of water effective to dissolve the polymer is usually preferably in the range of 40 to 99 wt%. In order to make the setting force sufficient, the water content is preferably 99 wt% or less, and 40 wt% or more is preferable from the viewpoint of easy viscosity and easy handling and cost.

  Moreover, when a thing with high hydrophobicity is included, solubility can be improved by using ethanol. The content of ethanol is usually preferably 40 wt% or less. For the purpose of reducing the volatile organic solvent, it is preferable that the ethanol content is low, more preferably 30 wt% or less, still more preferably 20 wt% or less, particularly preferably 10 wt% or less, and most preferably 5 wt%. % Or less.

  When used as an aqueous composition for hair cosmetics, additives can be blended within a range that does not significantly impair the performance, and the content is preferably 0 to 50 wt%. In order to impart the performance of the active ingredient and not hinder the performance, the content of other additives is preferably 0.1 to 30 wt%, more preferably 0.5 to 10 wt%, most preferably 0. 0.5 to 5 wt%.

  Preferably, the composition for hair cosmetics containing 0.1 to 10 wt% of silicones as one of the additives is mentioned. In order to give gloss to the hair and improve the combing, the hair cosmetic aqueous composition preferably contains 0.1 wt% or more of silicones, more preferably 0.2 wt% or more, and still more preferably. It is 0.3 wt% or more, and most preferably 0.5 wt% or more. Further, from the viewpoint of moderate viscosity and easy handling and cost, the silicone content is preferably 10 wt% or less, more preferably 5 wt% or less, and further preferably 2 wt% or less.

Here, the silicones refer to polymers having a structure in which silicon (organosilicon) to which organic groups are bonded and oxygen are alternately linked by chemical bonds. These may further have a substituent.
In addition, as an additive that can be blended in the aqueous composition for hair cosmetics of the present invention, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, a semipolar surfactant, Examples include higher alcohols, water-soluble polymers, cationic polymers, anionic polymers, nonionic polymers, amphoteric polymers, oil components, pearling agents, suspending agents, and the like.
Specific examples of the silicones and other additives are the same as those given as examples that can be used for the hair set composition described above.

<Cosmetic detergent composition>
The block polymer of the present invention can also be suitably used in a cosmetic detergent composition. In this case, the preferred composition is as follows.
0.1-20 wt% of block polymer of the present invention
Water 40-99wt%
Surfactant 1-40wt%
Additive 0-50wt%

  In the cosmetic detergent composition of the present invention, the block polymer of the present invention preferably contains 0.1 to 20 wt%. That is, the block polymer content is preferably 0.1 wt% or more, more preferably 0.2 wt% or more, and still more preferably 0.3 wt%, in order to ensure smoothness during rinsing and a feeling after drying. % Or more. In view of moderate viscosity and easy handling and cost, the block polymer content is preferably 20 wt% or less, more preferably 5 wt% or less, and even more preferably 1 wt% or less.

  The amount of water effective to dissolve the polymer is usually preferably in the range of 40 to 99 wt%. The water content is preferably 99 wt% or less, more preferably 90 wt% or less, and still more preferably 80 wt% or less, in order to ensure smoothness during rinsing and a feeling after washing and cleanability. Most preferably, it is 70 wt% or less. From the viewpoint of moderate viscosity and easy handling and cost, it is preferably 40 wt% or more, more preferably 50 wt% or more, and further preferably 60 wt% or more.

  The surfactant amount for imparting detergency is usually preferably in the range of 1 to 40 wt%. In order to obtain sufficient cleaning properties, the surfactant content is preferably 1 wt% or more, more preferably 5 wt% or more, still more preferably 10 wt% or more, and most preferably 15 wt% or more. is there. From the viewpoint of moderate viscosity and easy handling and cost, it is preferably 40 wt% or less, more preferably 30 wt% or less, and still more preferably 20 wt% or less.

  Examples of the surfactant include an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, and a semipolar surfactant. Especially, it is preferable to contain the anionic surfactant excellent in the detergency as a main component of a cleaning agent.

  The content of the anionic surfactant in the cosmetic detergent composition is preferably 5 to 20 wt%, more preferably 5 to 15 wt%, and still more preferably 7 to 13 wt%.

  Examples of the anionic surfactant include α-olefin sulfonate, higher alcohol sulfate, polyoxyethylene alkyl ether sulfate, paraffin sulfonate, polyoxyethylene alkyl ether carboxylate, alkyl sulfosuccinate. , N-acyl-β-alanine salts, N-acyl glutamate salts, acylmethyl taurine salts, and the like commonly used in detergent compositions can be used. Examples of counter ions of these anionic surfactants include sodium, potassium, ammonium, triethanolamine, diethanolamine and the like. Of these, polyoxyethylene alkyl ether sulfates are preferably used. An anionic surfactant may be used individually by 1 type, and may use 2 or more types together.

  Since the amphoteric surfactant has an effect of helping foaming, it is preferable to use it together with an anionic surfactant. The content of the amphoteric surfactant in the cosmetic detergent composition is preferably 1 to 10 wt%, more preferably 3 to 10 wt%, and even more preferably 3 to 8 wt%.

  Examples of amphoteric surfactants include those containing a betaine group and a long-chain alkyl group such as aminoacetic acid betaine, imidazolium betaine, sulfobetaine, and amidopropyl betaine. Of these, alkylamidopropylbetaine and the like are preferably used. These may be used alone or in combination of two or more.

  Since the semipolar surfactant has an effect of improving the smoothness at the time of rinsing, it is preferably used in combination with the anionic surfactant and the amphoteric surfactant. At this time, the content of the semipolar surfactant in the cosmetic cleaning composition is preferably 0.1 to 5 wt%, more preferably 0.5 to 5 wt%, and still more preferably 0.8. It is 5 to 3 wt%, and most preferably 0.5 to 2 wt%.

  Examples of the semipolar surfactant include lauramine oxide (lauryl dimethylamine oxide), which can be suitably used. Such surfactants are generally commercially available and can be used as they are. These may be used alone or in combination of two or more.

The cationic surfactant has an effect of improving the feeling after drying, and can be suitably used. The content of the cationic surfactant in the cosmetic detergent composition is preferably 0 to 3 wt%, more preferably 0.1 to 2 wt%, and still more preferably 0.2 to 1 wt%. .
As the cationic surfactant, for example, a long-chain alkyl group-containing quaternary ammonium salt is preferable. The long chain alkyl group is preferably one having 6 to 24 carbon atoms. Long chain alkyl group-containing quaternary ammonium salts include, for example, long chains such as cetyl trimethyl ammonium salt, stearyl trimethyl ammonium salt, behenyl trimethyl ammonium salt, cetyl dimethyl benzyl ammonium salt, stearyl dimethyl benzyl ammonium salt, and behenyl dimethyl benzyl ammonium salt. Two long chains such as one, dicetyldimethylammonium salt, distearyltrimethylammonium salt, dibehenyltrimethylammonium salt, dicetylmethylbenzylammonium salt, distearylmethylbenzylammonium salt, dibehenylmethylbenzylammonium salt And three long chains such as tricetylmethylammonium salt, tristearylmethylammonium salt, and tribehenylmethylammonium salt. And the like of it. Among them, one having one or two long chains is preferable, and one having one long chain is more preferable. These may be used alone or in combination of two or more.

Nonionic surfactants can be suitably used because they have a thickening effect. The content of the nonionic surfactant in the cosmetic cleaning composition is preferably 0 to 5 wt%, more preferably 0.1 to 3 wt%, and still more preferably 0.2 to 1 wt%. .
Examples of nonionic surfactants include polyoxyethylene hydrogenated castor oil, polyoxyethylene alkyl ether, fatty acid monoethanolamide, and fatty acid diethanolamide. These may be used alone or in combination of two or more.

  When used as a cosmetic cleaning composition, additives can be blended within a range that does not significantly impair the performance, and the content is preferably 0 to 50 wt%. In order to impart the performance of the active ingredient and not hinder the performance, the content of other additives is preferably 0.1 to 30 wt%, more preferably 0.5 to 10 wt%, most preferably 0. 0.5 to 5 wt%.

  Preferably, the cosmetic cleaning composition includes a composition containing 0.1 to 10 wt% of silicones as one of the additives. In order to give gloss to hair and improve combing, the cosmetic cleaning composition preferably contains 0.1 wt% or more of silicones, more preferably 0.2 wt% or more, and still more preferably It is 0.3 wt% or more, and most preferably 0.5 wt% or more. Further, from the viewpoint of moderate viscosity and easy handling and cost, the silicone content is preferably 10 wt% or less, more preferably 5 wt% or less, and further preferably 2 wt% or less.

Here, the silicones refer to polymers having a structure in which silicon (organosilicon) to which organic groups are bonded and oxygen are alternately linked by chemical bonds. These may further have a substituent.
In addition, other additives that can be blended in the cosmetic cleaning composition of the present invention include higher alcohols, water-soluble polymers, cationic polymers, anionic polymers, nonionic polymers, and amphoteric polymers. , Oil, pearling agent, suspending agent and the like.
Specific examples of silicones and other additives are the same as the examples given for the hair set agent composition described above.

  EXAMPLES The present invention will be described more specifically with reference to the following examples. However, the present invention is not limited to these examples unless it exceeds the gist.

[Synthesis of block polymer]
<Examples 1 to 6: Production of the present polymers (1) to (6)>
200 parts by weight of ethanol was charged into a reactor equipped with a reflux condenser, a dropping funnel, a thermometer, a nitrogen gas inlet tube and a stirring device, and the inside of the reactor was purged with nitrogen. The reactor was heated to 80 ° C., and 0.5 parts by weight of dimethyl-2,2′-azobisisobutyrate was added and stirred. A homogeneous mixture of monomer and solvent a described in composition A in Table 1 was added dropwise to the reactor over 1 hour. Heating and stirring were continued for 3 hours from the end of dropping.
Subsequently, 0.5 part by weight of dimethyl-2,2′-azobisisobutyrate was added and stirred, and then a homogeneous mixture of monomers of composition B in Table-1 and solvent b was added to this reactor. It was added dropwise over time. After 1 hour and 4 hours from the end of dropping, 0.5 parts by weight of dimethyl-2,2′-azobisisobutyrate was added. Thereafter, the mixture was further stirred for 3 hours with heating and cooled.

The polymers (1) to (6) synthesized in Examples 1 to 6 above were measured for viscosity and transmittance in an ethanol solution having a polymer solid content of 20% by weight, and the acid value was measured.
Viscosity was measured using a B-type viscometer. 2 was performed at 30 rpm and 25 ° C.
The transmittance was measured with a spectrophotometer when a 1 cm cell, a wavelength of 550 nm, and ethanol was used as a control solution.
In the measurement of the acid value, a polymer dissolved or dispersed in 100 g of distilled water was titrated with a 0.1N potassium hydroxide aqueous solution, and the required amount of potassium hydroxide per 1 g of the polymer was determined.
These measurement results are shown in Table 1.

<Comparative Examples 1-3: Production of Comparative Polymers (7)-(9)>
Polymers (7) to (9) were synthesized in the same manner as in Example 1 except that the monomer composition was changed to the composition shown in Table-2.
The polymers (7) to (9) synthesized in Comparative Examples 1 to 3 were measured for viscosity, transmittance, and acid value in the same manner as in Example 1.
In the polymer (7), a 20 wt% ethanol solution was phase-separated.
Other results are shown in Table 2.

[Performance evaluation]
Using the polymers (1) to (6), (8), and (9), a neutralized polymer solution neutralized with an acid value (actually measured value) and equimolar potassium hydroxide was prepared. The polymer concentration was 5% by weight, ethanol and distilled water were used as the solvent, and ethanol / distilled water = 1/2 (weight ratio).
The following evaluation was performed using this polymer neutralization liquid. The evaluation results are shown in Table-3.

<Curl retention>
2 g of the prepared polymer neutralizing solution was applied to 23 cm and 2 g of a bristled hair bundle, and immediately wound around a curler having a diameter of 2 cm. Next, the hair bundle was removed from the curler, and the apparent length (L0) of the hair bundle was measured. Next, this hair bundle was hung in a constant temperature and humidity chamber of 30 ° C. and 80% humidity, taken out after 3 hours, and the apparent length (L1) of the hair bundle was measured again. The set force was calculated from the obtained measurement value based on the following equation.
Setting force (%) = 100 × (23−L0) / (23−L1)
Curl retention was evaluated according to the following criteria based on the calculated setting force.
3 Setting force is 80% or more and 100% or less 2 Setting force is 70% or more and less than 80% 1 Setting force is 50% or more and less than 70% 0 Setting force is 0% or more and less than 50%

<Flexibility>
1 g of the prepared polymer neutralizing solution was applied to 23 cm and 2 g of a hair bundle having no habit, and dried. The softness was evaluated according to the following criteria from the hardness when the hair bundle was bent.
3 Maintains hardness no matter how many times it is bent.
2 The hardness is reduced by bending, but the shape is maintained.
1 Although it breaks, the shape is maintained slightly.
0 It broke and did not retain any hardness after that. brittle.

<No stickiness>
The hair bundles evaluated for flexibility were used as they were, and the non-stickiness was evaluated according to the following criteria from the degree of stickiness when touched by hand.
3 I do not feel any stickiness.
2 There is a slight stickiness.
1 I feel sticky.
0 The stickiness is intense.

<Smoothness of hair ends>
The hair bundle evaluated for non-stickiness was used as it was, and the non-stickiness and smoothness when the hair tips were touched by hand were evaluated according to the following criteria.
3 I don't feel any wrinkles. Smooth.
2 I feel a little bit rough.
1 I feel a crawl.
0 Gowaki is intense.

<No flaking>
The hair bundles evaluated for the smoothness of the bristles were used as they were, and the flaking state when the hair bundles were rubbed together by hand was visually observed and evaluated according to the following criteria.
3 Flaking is not seen at all.
2 Slight flaking is observed.
1 There is a lot of flaking.
0 Vigorous flaking is observed.

<Good fingering>
The hair bundle evaluated for lack of flaking was used as it was, and the lack of resistance when a finger was passed through the hair bundle was evaluated according to the following criteria.
3 Little resistance is felt.
2 Although the finger feels a little resistance, the finger passes smoothly up to the tip of the hair.
1 Feels resistance, making it difficult for your fingers to pass to the tip of your hair.
0 I feel resistance, and my fingers cannot pass to the tip of my hair.

From the above results, the following can be understood.
It can be seen that the block polymer of the comparative example is particularly poor in fingering, and it is difficult to achieve both curl retention and other properties with good fingering.
On the other hand, since the block polymer of the present invention has a branched structure via a linking monomer, it provides a uniform and low-viscosity solution even when the acid value is high, and provides curl retention, flexibility, and good fingering. An excellent hair cosmetic composition free of stickiness and flaking can be provided.
In addition, since the polymers (3) to (6) have the alkyl acrylate in the composition A, they are excellent in flexibility.
Furthermore, since the polymer (6) has an alkoxyalkyl acrylate in the composition A, it is particularly excellent in the smoothness of the hair tips.

Claims (5)

A block polymer in which two or more blocks composed of a monomer having a vinyl functional group are bonded via a linking monomer having a radical polymerizable vinyl functional group and a non-radical polymerizable functional group,
The two or more blocks include at least a first block and a second block having different monomer compositions from each other,
The block polymer whose acid value of this block polymer is the range of 200 mgKOH / g or more and 700 mgKOH / g or less. The block polymer according to claim 1, wherein the linking monomer is an oxazoline-based functional group-containing vinyl monomer represented by the following general formula (1).

(Wherein R ¹ represents a hydrogen atom or a methyl group, R ^{2 to} R ⁵ each independently represents a hydrogen atom, an alkyl group, an alkoxyalkyl group, an aryl group, an alkylaryl group, or an alkoxyaryl group; Represents any divalent linking group or direct bond.) The block polymer according to claim 1 or 2, wherein each of the first block and the second block has the following monomer composition.
(I) 1st block Linking monomer 0.1-20 wt%
Alkyl acrylate 1-99.9 wt%
Alkyl methacrylate 0-98wt%
Alkoxyalkyl (meth) acrylate 0-98wt%
(II) Second block 30% to 100% by weight of a vinyl monomer containing a carboxylic acid group
Hydrophilic vinyl monomer 0-70wt%
(However, hydrophilic vinyl monomers that do not contain carboxylic acid groups)
Hydrophobic vinyl monomer 0-70wt%   The block polymer of Claim 3 whose alkoxyalkyl (meth) acrylate is 1-98 wt% in the monomer composition of said 1st block. A block polymer in which two or more blocks composed of a monomer having a vinyl functional group are bonded via a linking monomer having a radical polymerizable vinyl functional group and a non-radical polymerizable functional group,
The two or more blocks include at least a first block and a second block each having a monomer composition different from each other, each consisting of the following monomer composition:
The linking monomer is an oxazoline-based functional group-containing vinyl monomer represented by the following general formula (1):
The block polymer whose acid value of this block polymer is the range of 300 mgKOH / g or more and 450 mgKOH / g or less.
(I) 1st block Linking monomer 0.1-20 wt%
Alkyl acrylate 60-99.9 wt%
Alkyl methacrylate 0-98wt%
Methoxyethyl (meth) acrylate 1-39 wt%
(II) Second block Vinyl monomer containing carboxylic acid group 70 to 100 wt%
Hydrophilic vinyl monomer 0-30wt%
(However, hydrophilic vinyl monomers that do not contain carboxylic acid groups)
Hydrophobic vinyl monomer 0-30wt%

(Wherein R ¹ represents a hydrogen atom or a methyl group, R ^{2 to} R ⁵ each independently represents a hydrogen atom, an alkyl group, an alkoxyalkyl group, an aryl group, an alkylaryl group, or an alkoxyaryl group; Represents any divalent linking group or direct bond.)