JP2021059635A - Active energy ray-curable composition and production method of the same - Google Patents

Abstract

To provide an active energy ray-curable composition and a production method of the composition that can give a cured product excellent in an elongation and a tensile product.SOLUTION: The active energy ray-curable composition comprises: a vinyl polymer (A) having at least two mercapto groups at a terminal and a number average molecular weight of 20,000 to 200,000; and an ethylenically unsaturated group-containing compound (B). A production method of the active energy ray-curable composition includes steps of: (1) polymerizing vinyl monomers by using a polymerization control agent having at least two thiocarbonylthio groups to obtain a polymer (P1) having at least two thiocarbonylthio groups at a terminal and a number average molecular weight of 20,000 to 200,000; (2) reacting a nucleophilic agent on the polymer (P1) obtained in step (1) to obtain the vinyl polymer (A) having at least two mercapto groups at a terminal and a number average molecular weight of 20,000 to 200,000; and (3) mixing the vinyl polymer (A) obtained in step (2) with the ethylenically unsaturated group-containing compound (B).SELECTED DRAWING: None

Description

The present invention relates to an active energy ray-curable composition and a method for producing the same.

The active energy ray-curable composition is applied to various uses such as a coating agent, an ink, a pattern forming agent, and an adhesive, and a radical-based active energy ray-curable composition is most used.
Among the radical-based active energy ray-curable curable compositions, the composition containing an acrylate compound as a main component has become the mainstream because of its high-speed curing and the large number of types of acrylate compounds. , There are problems such as inhibition of curing by oxygen and deterioration of adhesion due to curing shrinkage.
A thiol-ene-based curable composition is known as a radical-based active energy ray-curable curable composition that can overcome the above-mentioned problems.

Patent Document 1 contains (A) a polythiol, (B) a compound having a plurality of cyclic ene groups and not containing a (meth) acrylate group, and (C) a photoinitiator. The composition is disclosed. In the examples, low molecular weight polythiol such as pentaerythritol tetrakis (3-mercapto-propionate) is specifically disclosed as (A), and urethane dinorbornene oligomer is specifically disclosed as (B).

Further, Patent Document 2 describes (A) a thiol compound having two or more specific structures in the molecule, (B) a structure of an alicyclic or aromatic ring in the molecule, and two or more ethylenically unsaturated groups. A thiol-ene-based curable composition containing an enoligomer having a number average molecular weight of 500 to 20,000 in terms of polystyrene is disclosed. In the examples, low molecular weight polythiols such as pentaerythritol tetrakis (3-mercapto-propionate) as (A) and enoligomers having an allyl ether group as (B) are specifically disclosed.

International Publication No. 2004/101649 International Publication No. 2014/203779

However, the thiol-ene-based curable compositions described in Patent Documents 1 and 2 may have a problem of inferior flexibility and toughness when applied to applications such as sealing materials, packings, and elastomers. It was.
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an active energy ray-curable composition capable of obtaining a cured product having excellent elongation and tensile strength, and a method for producing the same. Is.

As a result of diligent studies to solve the above problems, the present inventors have made a vinyl polymer having two or more mercapto groups at the terminal and having a number average molecular weight in a specific range, and an ethylenically unsaturated group. The present invention has been completed by finding that an active energy ray-curable composition containing a compound can obtain a cured product having an excellent elongation and tensile strength.

（式中、Ｚは、−Ｒ^Ａ、−ＳＲ^Ａ、−ＯＲ^Ａ、又は−ＮＲ^ＡＲ^Ｂで示される基であり、Ｒ^Ａ及びＲ^Ｂは、同一又は異なって、置換基を有していてもよいアルキル基、置換基を有していてもよいアリール基、置換基を有していてもよいヘテロアリール基、又は置換基を有していてもよいアラルキル基を示す。Ｚが−ＮＲ^ＡＲ^Ｂで示される基のとき、Ｒ^Ａ及びＲ^Ｂは互いに結合して隣接する窒素原子と共に環を形成していてもよく、当該環は置換基を有していてもよい。）
で表される基を有するＲＡＦＴ剤である、〔４〕に記載の製造方法。
〔６〕前記ＲＡＦＴ剤が、式（１）：

（式中、Ｒは、酸素原子、窒素原子及び硫黄原子からなる群より選択される１種以上のヘテロ原子を有していてもよいｎ価の有機基を示し、ｎは２個以上の整数を示し、Ｚは前記に同じ。）
で表される化合物又はその塩である、〔５〕に記載の製造方法。
〔７〕前記ビニル系単量体の主成分が、炭素数１〜１２のアルキル基を有する（メタ）アクリル酸アルキルエステル化合物である、〔４〕〜〔６〕のいずれか一に記載の製造方法。
〔８〕前記エチレン性不飽和基含有化合物（Ｂ）が、（メタ）アリル基含有化合物、ビニル基含有化合物及び（メタ）アクリロイル基含有化合物からなる群より選択される少なくとも１種を含む、〔４〕〜〔７〕のいずれか一に記載の製造方法。
〔９〕硬化物の製造方法であって〔４〕〜〔８〕のいずれか一に記載の製造方法で得られた活性エネルギー線硬化型組成物を硬化する工程を含む、製造方法。 The present invention is as follows.
[1] An activity containing a vinyl polymer (A) having two or more mercapto groups at the terminal and a number average molecular weight of 20,000 to 200,000 and an ethylenically unsaturated group-containing compound (B). Energy ray curable composition.
[2] The active energy ray according to [1], wherein the vinyl-based polymer (A) contains a (meth) acrylic acid alkyl ester compound having an alkyl group having 1 to 12 carbon atoms as a main constituent monomer. Curable composition.
[3] The ethylenically unsaturated group-containing compound (B) contains at least one selected from the group consisting of a (meth) allyl group-containing compound, a vinyl group-containing compound and a (meth) acryloyl group-containing compound. The active energy ray-curable composition according to 1] or [2].
[4] A method for producing an active energy ray-curable composition.
(1) A vinyl-based monomer is polymerized using a polymerization control agent having two or more thiocarbonylthio groups to have two or more thiocarbonylthio groups at the terminals and a number average molecular weight of 20. A step of obtaining a polymer (P1) of 000 to 200,000,
(2) A nucleophile is reacted with the polymer (P1) obtained in the step (1) to have two or more mercapto groups at the terminals and a number average molecular weight of 20,000 to 200,000. The step of obtaining the vinyl-based polymer (A), which is
(3) A production method comprising a step of mixing the vinyl-based polymer (A) obtained in the step (2) and the ethylenically unsaturated group-containing compound (B).
[5] The polymerization control agent having two or more thiocarbonylthio groups has two or more formulas (1a) in the molecule:

^(Wherein, Z is a group represented by ^{-R A, -SR A, -OR A} , or ^-NR A ^{R B, R A} and ^{R B} are the same or different, have a substituent Indicates an alkyl group which may have an alkyl group, an aryl group which may have a substituent, a heteroaryl group which may have a substituent, or an aralkyl group which may have a substituent. Z is -NR. when the group represented by ^a R ^B, R ^a and R ^B may form a ring together with the adjacent nitrogen atom bonded to each other, the ring may have a substituent.)
The production method according to [4], which is a RAFT agent having a group represented by.
[6] The RAFT agent is based on the formula (1):

(In the formula, R represents an n-valent organic group which may have one or more heteroatoms selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom, and n is an integer of two or more. And Z is the same as above.)
The production method according to [5], which is a compound represented by (5) or a salt thereof.
[7] The production according to any one of [4] to [6], wherein the main component of the vinyl-based monomer is a (meth) acrylic acid alkyl ester compound having an alkyl group having 1 to 12 carbon atoms. Method.
[8] The ethylenically unsaturated group-containing compound (B) contains at least one selected from the group consisting of a (meth) allyl group-containing compound, a vinyl group-containing compound and a (meth) acryloyl group-containing compound. 4] The production method according to any one of [7].
[9] A production method comprising a step of curing an active energy ray-curable composition obtained by the production method according to any one of [4] to [8], which is a method for producing a cured product.

According to the active energy ray-curable composition of the present invention and the method for producing the same, a cured product having excellent elongation and tensile strength can be obtained.

Hereinafter, various embodiments of the techniques disclosed in the present specification will be described in detail. In the present specification, acrylate and / or methacrylate is referred to as (meth) acrylate, acryloyl group and / or methacrylic acid group is referred to as (meth) acryloyl group, and acrylic acid and / or methacrylic acid is referred to as (meth) acrylic acid. ..

The present invention is a vinyl-based polymer having two or more mercapto groups at the terminal and having a number average molecular weight of 20,000 to 200,000 (hereinafter, also referred to as “component (A)”) and ethylenically unsaturated. The present invention relates to an active energy ray-curable composition containing a saturated group-containing compound (B) (hereinafter, also referred to as “component (B)”).
Hereinafter, the component (A), the component (B), the active energy ray-curable composition and the method of using the composition will be described in detail.

1. 1. Component (A) Component (A) is a vinyl-based polymer having two or more mercapto groups at the terminals and having a number average molecular weight of 20,000 to 200,000.
By blending the component (A) and the component (B) described later, the active energy ray-curable composition of the present invention can be produced, and the coating film of the composition is irradiated with active energy rays. By doing so, the thiol-ene reaction proceeds, and a cured product can be produced.

The number average molecular weight (Mn) of the component (A) is in the range of 20,000 to 200,000. When the number average molecular weight is 20,000 or more, sufficient elongation and tensile product are exhibited, preferably 30,000 or more, and more preferably 50,000 or more. When the number average molecular weight is 200,000 or less, the viscosity is such that workability can be ensured, preferably 180,000 or less, and more preferably 150,000 or less.

The molecular weight distribution (Mw / Mn) obtained by dividing the value of the weight average molecular weight (Mw) of the component (A) by the value of the number average molecular weight (Mn) is 3.0 or less from the viewpoint of workability. Is preferable. It is more preferably 2.5 or less, further preferably 2.0 or less, still more preferably 1.5 or less. The lower limit of the molecular weight distribution is 1.0.

Examples of the method for producing the component (A) include the methods according to the following steps (1) and (2).
(1) A vinyl-based monomer is polymerized using a polymerization control agent having two or more thiocarbonylthio groups to have two or more thiocarbonylthio groups and a number average molecular weight of 20,000 to. A step of obtaining a polymer (P1) of 200,000,
(2) A nucleophile is reacted with the polymer (P1) obtained in the step (1) to have two or more mercapto groups at the terminals and a number average molecular weight of 20,000 to 200,000. A step of obtaining the vinyl-based polymer (A).

Step (1):
In step (1), a vinyl-based monomer is polymerized (living radical polymerization) using a polymerization control agent having two or more thiocarbonylthio groups in the presence of a polymerization initiator, and two or more thiocarbonyls. A polymer (P1) having a thio group is obtained. This reaction can be carried out in the presence or absence of a solvent.

When a solvent is used, a known solvent usually used for the polymerization reaction can be used. Examples thereof include nitrile solvents, aromatic solvents, ketone solvents, ester solvents, orthoester solvents, dimethylformamide, dimethyl sulfoxide, alcohol and water.
Specific examples of the nitrile solvent include acetonitrile, isobutyronitrile, benzonitrile and the like.
Specific examples of the aromatic solvent include benzene, toluene, xylene, anisole and the like.
Specific examples of the ketone solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and the like.
Specific examples of the ester solvent include methyl acetate, ethyl acetate, propyl acetate, butyl acetate and the like.
Specific examples of the orthoester solvent include trimethyl orthoacetate, triethyl orthoate, triethyl orthoate (n-propyl), tri (isopropyl) orthoatet, trimethyl orthoacetate, triethyl orthoacetate, triethyl orthopropionate, ortho n-. Examples thereof include trimethyl butyrate and trimethyl orthoisobutyrate.
As the solvent, one type or a combination of two or more types can be used.
This reaction may be carried out in the form of bulk polymerization or the like without using a solvent.

The vinyl-based monomer used for the polymerization is not particularly limited as long as it is capable of living radical polymerization (particularly RAFT polymerization), and examples thereof include a compound represented by the formula (2) or a salt thereof.

In the above formula (2), U and W are the same or different, -CO ₂ H, -CO ₂ R ¹ , -C (= O) R ¹ , -C (= S) R ¹ , -C ( = S) OR ¹ , -C (= O) SR ¹ , -C (= O) NH ₂ , -C (= O) NHR ¹ , -C (= O) N (R ¹ ) ₂ , hydrogen atom, halogen Indicates an atom or an alkyl group which may have a substituent. Alternatively, U and W may be bonded to each other to form a ring together with the adjacent −C = C−, and the ring may have a substituent.

When U and W are bonded to each other to form a ring together with the adjacent -C = C-, the ring includes a lactone, an acid anhydride, an imide ring and the like. The ring may have a substituent, and the substituents include a hydroxyl group, -CO ₂ H, -CO ₂ R ¹ , -C (= O) R ¹ , -C (= S) R ¹ , and so on. -CS (= O) R ¹ , -C (= O) SR ¹ , -CN, -C (= O) NH ₂ , -C (= O) NHR ¹ , -C (= O) NR ¹ ₂ ,- OR ¹ , -SR ¹ , -OC (= O) R ¹ , -SC (= O) R ¹ , -OC (= S) R ^{1, and the} like can be mentioned.

V is a hydrogen atom, R ¹ , -CO ₂ H, -CO ₂ R ¹ , -C (= O) R ¹ , -C (= S) R ¹ , -C (= S) OR ¹ , -C ( = O) SR ¹ , -C (= O) NH ₂ , -C (= O) NHR ¹ , -C (= O) N (R ¹ ) ₂ , -OR ¹ , -SR ¹ , -OC (= O) ) R ¹ , -SC (= O) R ¹ , or -OC (= S) R ¹ .

R ¹ is the same or different, an alkyl group which may have a substituent (particularly, a C1 to C20 alkyl group), and an alkenyl group which may have a substituent (particularly, a C2-C20 alkenyl group). , An alkynyl group which may have a substituent (particularly, C2-C20 alkynyl group), an aryl group which may have a substituent (particularly, a C6-C10 aryl group), and a substituent. May have heteroaryl groups (particularly C3 to C18 heteroaryl groups), cycloalkyl groups which may have substituents (particularly C3 to C18 cycloalkyl groups), heterocyclos which may have substituents. Alkyl groups (particularly C2-C18 heterocycloalkyl groups), aralkyl groups which may have substituents (particularly C7 to C22 aralkyl groups), heteroarylalkyl groups which may have substituents (particularly). , C4-C22 heteroarylalkyl groups), or polymer chains that may have substituents (eg, polyalkylene oxides, polyarylene ethers, etc.).

One aspect of R ^{1 is} a C1-C6 alkyl group which may have a substituent.
Examples of the ^{substituent that R 1} may have include an epoxy group, a hydroxyl group, an alkoxy group, an acyl group, an acyloxy group, a formyl group, an alkylcarbonyl group, a carboxyl group, a sulfonic acid group, an alkoxycarbonyl group and an aryl. Examples thereof include an oxycarbonyl group, an isocyanato group, a cyano group, a silyl group, a halogen atom and an amino group.

Examples of the compound represented by the formula (2) or a salt thereof include maleic anhydride, N-alkylmaleimide, N-arylmaleimide, dialkylfumarate, (meth) acrylic acid ester, (meth) acrylic acid, and styrene. , (Meta) acrylamide, (meth) acrylonitrile, and mixtures of these monomers.

Specific examples of the compound represented by the formula (2) or a salt thereof include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylic. 2-Ethylhexyl acid, isobornyl (meth) acrylate, (meth) acrylic acid, benzyl (meth) acrylate, phenyl (meth) acrylate, (meth) acrylonitrile, alpha-methylstyrene, styrene; glycidyl (meth) acrylate , 2-Hydroxyethyl (meth) acrylate, Hydroxypropyl (meth) acrylate, Hydroxybutyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylamino (meth) acrylate Ethyl, triethylene glycol (meth) acrylate, anhydrous itaconic acid, itaconic acid, (meth) acrylamide, N-methyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N-tert-butyl (meth) Acrylamide, Nn-butyl (meth) acrylamide, N-methylol (meth) acrylamide, N-ethylol (meth) acrylamide, N-tert-butyl (meth) allylamide, Nn-butyl (meth) allylamide, N- Methylol (meth) allylamide, N-ethylol (meth) allylamide, vinyl benzoate, diethylaminostyrene, alpha-methylbenzoate vinyl, diethylaminoalpha-methylstyrene, p-vinylbenzenesulfonic acid, p-vinylbenzenesulfonic acid sodium salt, Trimethoxysilylpropyl (meth) acrylate, triethoxysilylpropyl (meth) acrylate, tributoxysilylpropyl (meth) acrylate, dimethoxymethylsilylpropyl (meth) acrylate, diethoxymethylsilylpropyl (meth) acrylate , (Meta) dibutoxymethylsilylpropyl acrylate, (meth) diisopropoxymethylsilylpropyl acrylate, (meth) dimethoxysilylpropyl acrylate, (meth) diethoxysilylpropyl acrylate, (meth) dibutoxy acrylate Cyrilpropyl, diisopropoxysilylpropyl (meth) acrylate, vinyl acetate, butyl butyrate, vinyl benzoate, vinyl chloride, vinyl fluoride, vinyl bromide, maleic anhydride, N-phenylmaleimide, N-butylmaleimide, N -Vinylpyrrolidone, N-vinylcarbazole and the like can be mentioned. When the group contained in each compound contains an isomer, the group is interpreted as containing any isomer.

The vinyl-based monomer used in the present invention may contain the compound represented by the above formula (2) or a salt thereof, and if necessary, other monomers.

The polymerization initiator is not particularly limited as long as it usually produces free radicals used for RAFT polymerization. Examples thereof include thermal polymerization initiators (peroxides, peroxides, azo compounds, etc.); photopolymerization initiators; redox polymerization initiators, and the like. Further, a free radical generation means using high-energy radiation such as electron beam, X-ray, gamma ray or the like may be used.

Examples of the thermal polymerization initiator include 2,2'-azobis (isobutyronitrile), 2,2'-azobis (2-cyanobutane), dimethyl 2,2'-azobis (isobutyrate), 4,4'-. Azobis (4-cyanovalerian acid), 1,1'-azobis (cyclohexanecarbonitrile) (ACHN), 2,2'-azobis (2-methylbutyronitrile) (ABN-E), 2- (t-butylazo ) -2-Cyanopropane, 2,2'-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2'-azobis [2-methyl -N- (2-Hydroxyethyl) propionamide] (AMHP), 4,4'-azobis (4-cyanopentanoic acid) (ACPA), 2,2'-azobis (5-hydroxy-2methylpentanenitrile) ( AHPN), 2,2'-azobis (N, N'-dimethyleneisobutyramidine) dihydrochloride, 2,2'-azobis (2-amidinopropane) dihydrochloride, 2,2'-azobis (N, N'- Dimethyleneisobutyramidine), 2,2'-azobis {2-methyl-N- [1,1-bis (hydroxymethyl) -2-hydroxyethyl] propionamide}, 2,2'-azobis {2-methyl- N- [1,1-bis (hydroxymethyl) -2-ethyl] propionamide}, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2'-azobis (Isobutylamide) dihydrate, 2,2'-azobis (2,2,4-trimethylpentane), 2,2'-azobis (2-methylpropane), t-butylperoxyacetate, t-butylper Oxybenzoate, t-butylperoxyneodecanoate, t-butylperoxyisobutyrate, t-amylperoxypivalate, t-butylperoxypivalate, diisopropylperoxydicarbonate, dicyclohexylperoxydicarbonate, Dicumyl peroxide, dibenzoyl peroxide (BPO), dilaurolyl peroxide (LPO), potassium peroxydisulfate, ammonium peroxydisulfate, tert-butyl 2-ethylhexaneperoxoate, di-t -Butyl hyponitrite, dicumyl hyponitrite and the like can be mentioned. One of these, or a combination of two or more, can be selected.

As the photopolymerization initiator, for example, a benzene derivative, a benzophenone, an acylphosphine oxide, and a photooxidation-reduction system are selected.

Examples of the redox polymerization initiator include the following oxides (potassium, peroxydisulfate, hydrogen peroxide, t-butylhydroperoxide, etc.) and reducers (iron (II), titanium (III), thio). A combination of potassium sulfate, potassium hydrogen peroxide, etc.) can be mentioned.

As other suitable polymerization initiators and methods, known ones can be adopted.

Examples of the polymerization initiator that is easily dissolved in a hydrophilic solvent include 4,4-azobis (cyanovalerian acid) and 2,2'-azobis {2-methyl-N- [1,1-bis (hydroxymethyl)-. 2-Hydroxyethyl] propionamide}, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2'-azobis (N, N'-dimethyleneisobutyramidine), 2,2'-azobis (N, N'-dimethyleneisobutyramidine) dihydrochloride, 2,2'-azobis (2-amidinopropane) dihydrochloride, 2,2'-azobis {2-methyl-N- [1 , 1-bis (hydroxymethyl) -2-ethyl] propionamide}, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide], 2,2'-azobis (isobutylamide) Examples include, but are not limited to, dihydrates and derivatives thereof.

Examples of the polymerization initiator that is easily dissolved in a hydrophobic solvent include azo compounds, and examples thereof include known substances 2,2'-azobisisobutyronitrile.
Other suitable initiator compounds include acyl peroxides such as acetyl peroxide and benzoyl peroxide, and alkyl peroxides such as t-butyl α-cumyl peroxide. Hydroperoxides such as t-butyl hydroperoxide and Kumil hydroperoxide can also be used.

The amount of the polymerization initiator used can be appropriately set according to various conditions such as the type and amount of the vinyl-based monomer, and is not particularly limited. For example, from the viewpoint of obtaining a polymer having a smaller molecular weight distribution, the amount of the radical polymerization initiator used per 1 mol of the polymerization control agent (particularly RAFT agent) having two or more thiocarbonylthio groups is 0.5 mol. The amount is preferably 0 or less, and more preferably 0.2 mol or less. Further, from the viewpoint of stably performing the polymerization reaction, the amount of the radical polymerization initiator used with respect to 1 mol of the polymerization control agent is preferably 0.001 mol or more, and more preferably 0.005 mol or more. .. Therefore, the amount of the radical polymerization initiator used with respect to 1 mol of the polymerization control agent is preferably in the range of 0.001 mol or more and 0.5 mol or less, and more preferably in the range of 0.005 mol or more and 0.2 mol or less.

The reaction temperature during the polymerization reaction by the RAFT method is preferably 30 ° C. or higher and 120 ° C. or lower, more preferably 40 ° C. or higher and 110 ° C. or lower, and further preferably 50 ° C. or higher and 100 ° C. or lower. When the reaction temperature is 30 ° C. or higher, the polymerization reaction can proceed smoothly. On the other hand, when the reaction temperature is 120 ° C. or lower, side reactions can be suppressed and restrictions on the initiators and solvents that can be used are relaxed.

（式中、Ｚは、−Ｒ^Ａ、−ＳＲ^Ａ、−ＯＲ^Ａ、又は−ＮＲ^ＡＲ^Ｂで示される基であり、Ｒ^Ａ及びＲ^Ｂは、同一又は異なって、置換基を有していてもよいアルキル基、置換基を有していてもよいアリール基、置換基を有していてもよいヘテロアリール基、又は置換基を有していてもよいアラルキル基を示す。Ｚが−ＮＲ^ＡＲ^Ｂで示される基のとき、Ｒ^Ａ及びＲ^Ｂは互いに結合して隣接する窒素原子と共に環を形成していてもよく、当該環は置換基を有していてもよい。）
で表される基を有するＲＡＦＴ剤が挙げられる。 Examples of the polymerization control agent having two or more thiocarbonylthio groups include two or more formulas (1a) in the molecule.

^(Wherein, Z is a group represented by ^{-R A, -SR A, -OR A} , or ^-NR A ^{R B, R A} and ^{R B} are the same or different, have a substituent Indicates an alkyl group which may have an alkyl group, an aryl group which may have a substituent, a heteroaryl group which may have a substituent, or an aralkyl group which may have a substituent. Z is -NR. when the group represented by ^a R ^B, R ^a and R ^B may form a ring together with the adjacent nitrogen atom bonded to each other, the ring may have a substituent.)
RAFT agents having a group represented by.

As "alkyl group" of the "optionally substituted alkyl group" represented by R ^A and ^{R B,} alkyl of C1~C20 linear or branched (more C1 -C10, particularly C1 -C6) The group is mentioned. Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a tert-butyl group, a dodecyl group, a lauryl group and a stearyl group. When the "alkyl group" has a substituent, the substituents include, for example, an epoxy group, a hydroxyl group, an alkoxy group, an acyl group, an acyloxy group, a formyl group, an alkylcarbonyl group, a carboxyl group, a sulfonic acid group and an alkoxycarbonyl group. , Aryloxycarbonyl group, isocyanato group, cyano group, silyl group, halogen atom, amino group and the like. The "alkyl group" may have one or more substituents selected from these substituents.

As the "aryl group" of the "optionally substituted aryl group" represented by R ^A and R ^B, it means a monovalent group obtained by removing one hydrogen atom from an aromatic hydrocarbon, e.g. , C6 to C20 aryl groups in which a single ring or two or more rings are fused. Examples of the aryl group include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthrasenyl group and the like. When the "aryl group" has a substituent, the substituents include, for example, an epoxy group, a hydroxyl group, an alkoxy group, an acyl group, an acyloxy group, a formyl group, an alkylcarbonyl group, a carboxyl group, a sulfonic acid group and an alkoxycarbonyl group. , Aryloxycarbonyl group, isocyanato group, cyano group, silyl group, halogen atom, amino group and the like. The "aryl group" may have one or more substituents selected from these substituents.

As "heteroaryl group" of the "heteroaryl group optionally having a substituent" represented by R ^A and R ^B, refers to a monovalent group derived by removing one hydrogen atom from heteroaromatic hydrocarbons Then, for example, a heteroaryl group of C5 to C20 in which a single ring or two or more rings are fused can be mentioned. Examples of the heteroaryl group include a pyridyl group, a quinolyl group, an isoquinolyl group, a pyrimidinyl group and the like. When the "heteroaryl group" has a substituent, the substituents include, for example, an epoxy group, a hydroxyl group, an alkoxy group, an acyl group, an acyloxy group, a formyl group, an alkylcarbonyl group, a carboxyl group, a sulfonic acid group and an alkoxycarbonyl. Examples thereof include a group, an aryloxycarbonyl group, an isocyanato group, a cyano group, a silyl group, a halogen atom and an amino group. The "heteroaryl group" may have one or more substituents selected from these substituents.

As "aralkyl group" of "optionally substituted aralkyl group represented by R ^A and R ^B, 1 or more hydrogen atoms on the above-mentioned" alkyl group "is substituted with the above" aryl group " Means a group. When the "aralkyl group" has a substituent, examples of the substituent include those listed as the substituents of the above-mentioned "alkyl group" and "aryl group".

When the group Z is represented by -NR ^A R ^B, as the ring formed together with the nitrogen atom R ^A and R ^B are adjacent bonded together, for example, a pyrrole ring, a pyrazole ring, an imidazole ring, pyrrolidine ring, piperidine Examples thereof include a ring, a piperazine ring, a pyridine ring, a pyrimidine ring, a pyrazine ring, an oxazole ring, a thiazole ring, a morpholine ring, a thiazine ring, and a triazole ring. When the ring has a substituent, the substituent includes, for example, an alkyl group (C1 to C6 alkyl group, etc.), an oxo group (= O), an epoxy group, a hydroxyl group, an alkoxy group, an acyl group, an acyloxy group, and a formyl. Examples thereof include a group, an alkylcarbonyl group, a carboxyl group, a sulfonic acid group, an alkoxycarbonyl group, an aryloxycarbonyl group, an isocyanato group, a cyano group, a silyl group, a halogen atom and an amino group. The ring may have one or more substituents selected from these substituents.

Z is preferably the group represented by -SR ^A.

（式中、Ｒは、酸素原子、窒素原子及び硫黄原子からなる群より選択される１種以上のヘテロ原子を有していてもよいｎ価の有機基を示し、ｎは２個以上の整数を示し、Ｚは前記に同じ。）
で表される化合物又はその塩が挙げられる。 As a specific example of the RAFT agent having two or more groups represented by the formula (1a) in the molecule, the formula (1):

(In the formula, R represents an n-valent organic group which may have one or more heteroatoms selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom, and n is an integer of two or more. And Z is the same as above.)
Examples thereof include a compound represented by (1) or a salt thereof.

The n-valent organic group represented by R has a carbon atom bonded to a group represented by -SC (= S) -Z (a group represented by the formula (1a)), and the carbon thereof. Atomic atoms can serve as a starting point for living radical polymerization (particularly RAFT polymerization) reactions with vinyl-based monomers. From the viewpoint of the reactivity of RAFT polymerization and the like, the carbon atom is preferably bonded to sp ² hybrid orbital carbon or sp hybrid orbital carbon contained in R. Examples of the sp ² hybrid orbital carbon or the sp hybrid orbital carbon include a carbon atom on an aromatic ring, a carbon atom on a heteroaromatic ring, a carbon atom of a carbonyl group (C = O), a carbon atom of a cyano group, and the like. Be done.

The RAFT agent represented by the formula (1) is a known method, for example, Macromolecules 2003, 36, 2273-2283, Macromolecules 2005, 38, 9518-9525, Macromolecules 2007, 40, 4446-4455, Macromolecules 2012, 45, 4205-4215, J. Am. Chem. Soc. 2008, 130, 12242-12243, J. Am. Chem. Soc. 2011, 133, 15707-15713, Patent No. 6174036, etc. it can.

The amount of the polymerization control agent (RAFT agent) having two or more thiocarbonylthio groups is not particularly limited, and can be appropriately set according to the target number average molecular weight (20,000 to 200,000). ..

The living radical polymerization reaction is preferably carried out in an atmosphere of an inert gas containing no oxygen. The reaction temperature during the polymerization reaction is preferably 40 ° C. or higher and 100 ° C. or lower, more preferably 45 ° C. or higher and 90 ° C. or lower, and further preferably 50 ° C. or higher and 80 ° C. or lower. When the reaction temperature is 40 ° C. or higher, the polymerization reaction can proceed smoothly. On the other hand, when the reaction temperature is 100 ° C. or lower, side reactions can be suppressed and restrictions on the initiators and solvents that can be used are relaxed.

（式中、ｋは１以上を示し、他の記号は前記に同じ。） One form of step (1) can be expressed as follows. That is, it is represented by the formula (3) by polymerizing the vinyl-based monomer represented by the formula (2) using the RAFT agent represented by the formula (1) in the presence of the polymerization initiator. The polymer (P1) can be produced.

(In the formula, k indicates 1 or more, and other symbols are the same as above.)

k can be arbitrarily set according to the degree of polymerization (target number average molecular weight (Mn)). U, V and W can be converted to the desired functional group in step (1) or by an additional step.

After completion of the reaction, it is isolated or purified using a known treatment method such as reprecipitation treatment or vacuum drying, has two or more thiocarbonylthio groups, and has a number average molecular weight (Mn) of 20,000 to 200. A polymer (P1) of 000 can be obtained.

In the step (1), the main component of the vinyl-based monomer is a (meth) acrylic acid alkyl ester compound having an alkyl group having 1 to 12 carbon atoms, so that the vinyl-based monomer has an alkyl group having 1 to 12 carbon atoms (1). A polymer (P1) containing a meta) acrylic acid alkyl ester compound as a main constituent monomer can be obtained. In this case, in step (2), a vinyl-based polymer (A) containing a (meth) acrylic acid alkyl ester compound having an alkyl group having 1 to 12 carbon atoms as a main constituent monomer can be produced. It is preferable in that the cured product of the active energy ray-curable composition containing the vinyl-based polymer (A) is excellent in elongation and tensile strength.

Step (2):
In step (2), a nucleophile is usually reacted with the polymer (P1) obtained in step (1) in the presence of a solvent to remove thiocarbonyl groups, and two or more at the ends. A vinyl-based polymer (A) having a mercapto group (-SH) is obtained.

As the solvent, a known solvent usually used for the nucleophilic reaction can be used. Examples thereof include nitrile solvents, aromatic solvents, ketone solvents, ester solvents, orthoester solvents, dimethylformamide, dimethyl sulfoxide, alcohol and water.
Specific examples of the nitrile solvent include acetonitrile, isobutyronitrile, benzonitrile and the like.
Specific examples of the aromatic solvent include benzene, toluene, xylene, anisole and the like.
Specific examples of the ketone solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and the like.
Specific examples of the ester solvent include methyl acetate, ethyl acetate, propyl acetate, butyl acetate and the like.
Specific examples of the orthoester solvent include trimethyl orthoacetate, triethyl orthoate, triethyl orthoate (n-propyl), tri (isopropyl) orthoatet, trimethyl orthoacetate, triethyl orthoacetate, triethyl orthopropionate, ortho n-. Examples thereof include trimethyl butyrate and trimethyl orthoisobutyrate.
These can be used alone or in combination of two or more.

The nucleophile is not particularly limited as long as it can convert a thiocarbonylthio group into a mercapto group. Examples include nucleophilic reagents such as ammonia, amine compounds, hydroxides, and thiols. Of these, amine compounds such as primary or secondary amine compounds are preferable. Specific examples thereof include ethylamine, n-propylamine, isopropylamine, butylamine, hexylamine, octylamine, benzylamine, ethylenediamine, hydrazine, piperidine, aminoethanol, and combinations thereof.

The amount of the nucleophile to be used can usually be appropriately selected according to the equivalent amount of the thiocarbonylthio group contained in the polymer (P1). From the viewpoint of reaction efficiency, the molar equivalent of the nucleophile with respect to the thiocarbonylthio group is preferably 1 molar equivalent or more, more preferably 10 molar equivalent or more, and particularly preferably 20 molar equivalent or more. Further, from the viewpoint that the influence of the odor by the unreacted nucleophile is small, 70 molar equivalents or less is preferable, 60 molar equivalents or less is further preferable, and 50 molar equivalents or less is particularly preferable.

Such a reaction of removing a thiocarbonyl group from a polymer (P1) having two or more thiocarbonylthio groups using an amine compound may be referred to as amino decomposition.

When the thiocarbonyl group is removed by amino decomposition, it is preferable that oxygen is removed from the reaction system so that the mercapto group produced is not oxidized to form a sulfide (SS). For example, along with the removal of oxygen, a reducing agent can be supplied to the solution of the polymer (P1) to suppress disulfide formation.

As the reducing agent, for example, zinc / acid acid, tributylphosphine, tris (2-carboxyethyl) phosphine (TCEP), NaBH ₄ used with _{tributylphosphine, LiBH (C 2 H 5)} 3 , etc. borohydride, dimethyl Examples include phenylphosphine (DMPP), sodium dithionite (Na ₂ S ₂ O ₄ ), sodium borohydride (NaHSO ₃ ), ethylenediaminetetra (acetic acid) (EDTA), and combinations thereof.

The reaction temperature is preferably 10 ° C. or higher, more preferably 15 ° C. or higher, and particularly preferably 25 ° C. or higher from the viewpoint of reaction efficiency. Further, from the viewpoint that side reactions such as a nucleophilic reaction on the polymer main chain are unlikely to occur, 80 ° C. or lower is preferable, 60 ° C. or lower is further preferable, and 50 ° C. or lower is particularly preferable.

From the viewpoint of reaction efficiency, the reaction time is preferably 1 hour or longer, more preferably 2 hours or longer, and particularly preferably 3 hours or longer. Further, from the viewpoint that side reactions such as a nucleophilic reaction on the polymer main chain are unlikely to occur, 48 hours or less is preferable, 36 hours or less is further preferable, and 24 hours or less is particularly preferable.

The progress of the reaction can be monitored, for example, as follows. A part of the solution is withdrawn, the solution is reprecipitated, purified and vacuum dried to prepare a sample, and ¹ H-NMR measurement shows that the proton-derived peak on the carbon to which the RAFT group is bonded disappears and is generated. It was observed that a proton-derived peak on the carbon to which the SH group was bonded appeared. From this peak integral value and the characteristic proton-derived peak integral value present at the start end, the number of SH groups per molecule can be confirmed.

（式中、記号は前記に同じ。） One form of step (2) can be expressed as follows. That is, the vinyl-based polymer (A) represented by the formula (4) can be produced by reacting the nucleophile with the polymer (P1) represented by the formula (3).

(In the formula, the symbols are the same as above.)

After completion of the reaction, it is isolated or purified using a known treatment method such as reprecipitation treatment or vacuum drying, has two or more mercapto groups, and has a number average molecular weight (Mn) of 20,000 to 200,000. The vinyl-based polymer (A) is obtained and can be used in an active energy ray-curable composition. Alternatively, it is isolated using a solution containing a vinyl polymer (A) having two or more mercapto groups obtained in this reaction and having a number average molecular weight (Mn) of 20,000 to 200,000. Alternatively, it can be applied to an active energy ray-curable composition without purification.

2. Component (B) As the component (B), various compounds can be used as long as the compound has one or more ethylenically unsaturated group-containing compounds, and a (meth) allyl group-containing compound, a vinyl group-containing compound, and (meth). ) Acryloyl group-containing compounds and the like can be mentioned. As the component (B), only one type may be used alone, or two or more types may be used in combination.

The component (B) preferably contains at least one selected from the group consisting of a (meth) allyl group-containing compound, a vinyl group-containing compound, and a (meth) acryloyl group-containing compound, and the elongation rate and resistance of the cured product are preferably contained. It is particularly preferable to contain a (meth) allyl group-containing compound and / or a vinyl group-containing compound from the viewpoint of excellent stacking.

When a vinyl-based polymer having two mercapto groups at the terminal is used as the component (A), a monofunctional (meth) acrylamide compound and / or a monofunctional (meth) acrylate is used as the component (B). Is preferable because a triblock copolymer having excellent elongation and tensile strength can be easily produced.

Examples of the (meth) allyl group-containing compound include monofunctional allyl compounds and polyfunctional allyl compounds. Specific examples of the monofunctional allyl compound include (meth) allyl alcohol, and specific examples of the polyfunctional allyl compound include trimethylolpropanediallyl ether, trimethylolpropanetriallyl ether, pentaerythritol diallyl ether, and pentaerythritol. Examples thereof include triallyl ether, tetraallyloxyethane, polyallyl saccharose, di (meth) allyl phthalate, tri (meth) allyl isocyanurate, and tri (meth) allyl cyanurate.

Examples of the vinyl group-containing compound include a monofunctional vinyl compound and a polyfunctional vinyl compound. Specific examples of the monofunctional vinyl compound include styrene, vinyltoluene, N-vinylpyrrolidone, N-vinylcaprolactam, vinylimidazole, vinylpyridine and the like, and specific examples of the polyfunctional vinyl compound include hexanediol dinorbornene carboxy. Examples thereof include vinyl ethers such as rate, pentaerythritol tetranorbornene carboxylate, triethylene glycol divinyl ether, cyclohexanedimethanol divinyl ether, cyclohexanediol divinyl ether, and divinylbenzene.

Examples of the (meth) acryloyl group-containing compound include a monofunctional (meth) acrylamide compound, a polyfunctional (meth) acrylamide compound, a monofunctional (meth) acrylate, and a polyfunctional (meth) acrylate.

Specific examples of monofunctional (meth) acrylamide compounds include diacetone (meth) acrylamide, isobutoxymethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, t-octyl (meth) acrylamide, N, N-diethyl. Examples thereof include (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, (meth) acryloylmorpholin, acrylamide-2-methylpropanesulfonic acid, N-isopropyl (meth) acrylamide and the like.
Specific examples of the polyfunctional (meth) acrylamide compound include N, N'-diacryloyl-4,7,10-trioxa-1,13-tridecanediamine, N, N', N''-triacryloyldiethylenetriamine, N, N', N'', N'''-tetraacryloyl triethylenetetramine, N, N'-{[2-acrylamide-2-[(3-acrylamide propoxy) methyl] propan-1,3-diyl) Bis (oxy)] Bis (propane-1,3-diyl)} Diacrylamide and the like can be mentioned.

Specific examples of the monofunctional (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, and 2-. Ethylhexyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, cyclopentanyl (meth) acrylate, Dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, benzyl (meth) acrylate, phenol alkylene oxide adduct (meth) acrylate, p-cumylphenol alkylene oxide adduct (meth) acrylate, (Meta) acrylate of o-phenylphenol alkylene oxide adduct, (meth) acrylate of nonylphenol alkylene oxide adduct, 2-methoxyethyl (meth) acrylate, ethoxyethoxyethyl (meth) acrylate, alkylene oxide addition of 2-ethylhexyl alcohol (Meta) acrylates, tetrahydrofurfuryl (meth) acrylates, caprolactone-modified tetrahydrofurfuryl (meth) acrylates, (2-ethyl-2-methyl-1,3-dioxolan-4-yl) methyl (meth) acrylates, (2-Isobutyl-2-methyl-1,3-dioxolan-4-yl) methyl (meth) acrylate, (1,4-dioxaspiro [4,5] decane-2-yl) methyl (meth) acrylate, glycidyl ( Meta) acrylate, 3,4-epoxycyclohexylmethyl (meth) acrylate, (3-ethyloxetane-3-yl) methyl (meth) acrylate, 2- (meth) acryloyloxyethyl isocyanate, allyl (meth) acrylate, N- (Meta) Acryloyloxyethyl Hexahydrophthalimide, N- (Meta) Acryloyloxyethyl Tetrahydrophthalimide, 2- (Meta) Acryloyloxyethyl Hexahydrophthalic Acid, 2- (Meta) Acryloyloxyethyl Succinic Acid, ω-carboxy-Poly Caprolactone mono (meth) acrylate, 2- (meth) acryloyloxyethyl acid phosphate, 3-( Examples thereof include meta) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyldimethoxymethylsilane, 3- (meth) acryloyloxypropyltriethoxysilane, and 2- (meth) acryloyloxyethyl acid phosphate.
In the alkylene oxide adduct, examples of the alkylene oxide include ethylene oxide and propylene oxide.

Specific examples of the polyfunctional (meth) acrylate include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and 1 , 6-Hexanediol di (meth) acrylate, 3-methyl-1,5-pentanediol di (meth) acrylate, 2-butyl-2-ethyl-1,3-propanediol di (meth) acrylate and 1,9 -Di (meth) acrylate of an aliphatic diol such as nonane diol di (meth) acrylate;
Di (meth) acrylates of alicyclic diols such as cyclohexanedimethylol di (meth) acrylate and tricyclodecanedimethylol di (meth) acrylate;
Diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, alkylene glycol di (meth) acrylate such as triethylene glycol di (meth) acrylate and tripropylene glycol di (meth) acrylate;
The esterification reaction product of neopentyl glycol, hydroxypivalic acid and (meth) acrylic acid (hereinafter referred to as "hydroxypivalate neopentyl glycol di (meth) acrylate"), caprolactone-modified hydroxypivalate neopentyl glycol di (meth). ) Acrylate;
Di (meth) acrylate of alkylene oxide adduct of bisphenol compound such as di (meth) acrylate of bisphenol A alkylene oxide adduct;
Di (meth) acrylate of hydrogenated bisphenol compound such as di (meth) acrylate of hydrogenated bisphenol A;
Di (meth) acrylate of isocyanuric acid alkylene oxide adduct, tri (meth) acrylate of isocyanuric acid alkylene oxide adduct, di (meth) acrylate of caprolactone-modified isocyanuric acid alkylene oxide adduct, caprolactone-modified isocyanuric acid alkylene oxide adduct Poly (meth) acrylates of isocyanuric acid alkylene oxide adducts such as tri (meth) acrylates;
Polyester poly (meth) acrylates such as trimethylolpropane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tri or tetra (meth) acrylate, dipentaerythritol penta or hexa (meth) acrylate;
Tri (meth) acrylate of trimethylolpropane alkylene oxide adduct, tetra (meth) acrylate of trimethylolpropane alkylene oxide adduct, tri or tetra (meth) acrylate of pentaerythritol alkylene oxide adduct, dipentaerythritol alkylene oxide adduct Poly (meth) acrylates of polyol alkylene oxide adducts such as penta or hexa (meth) acrylates:
Examples thereof include urethane (meth) acrylate; epoxy (meth) acrylate; and polyester (meth) acrylate.
In the alkylene oxide adduct, examples of the alkylene oxide include ethylene oxide and propylene oxide.

In addition to these, compounds and the like described on pages 53 to 56 of the document "Latest UV Curing Technology" [Printing Information Association, Inc., published in 1991] can be mentioned.

3. 3. Active energy ray-curable composition The active energy ray-curable composition of the present invention requires the above-mentioned components (A) and (B).
The preferable ratios of the component (A) and the component (B) in the active energy ray-curable composition are as follows.
When the component (B) has two or more ethylenically unsaturated groups, the mercapto group in the component (A) and the mercapto group in the component (B) are converted into molars of the mercapto group and the ethylenically unsaturated group, respectively. The ethylenically unsaturated group in the component (B) is preferably 0.3 to 3.0 mol with respect to 1.0 mol. If the ethylenically unsaturated group of the component (B) is less than 0.3 mol, the curability at the time of irradiation with active energy rays may be insufficient, and if it exceeds 3.0 mol, the curability is insufficient. Or the tensile properties may decrease.
When the component (B) has one ethylenically unsaturated group, it is preferably 10 to 60 parts by mass with respect to 100 parts by mass of the component (A). If the component (B) is less than 10 parts by mass, the curability at the time of irradiation with active energy rays may be insufficient, and if it exceeds 60 parts by mass, the curability may be insufficient or the tensile physical characteristics may be deteriorated. May be done.

As a method for producing the active energy ray-curable composition of the present invention, a conventional method may be followed, and the components (A) and (B), and if necessary, other components are further stirred and mixed according to a conventional method. It can be manufactured by. In this case, it can be heated or heated as needed.

The viscosity of the active energy ray-curable composition of the present invention may be appropriately set according to the purpose of use, and a known organic solvent may be used.

Other components include photoradical polymerization initiators, ultraviolet absorbers, light stabilizers, antioxidants, polymerization inhibitors, silane coupling agents, polymers, tackifiers, fillers, metal fine particles, metal oxide fine particles, and ion traps. Examples include agents, defoaming agents, leveling agents, pigments and pigments.

Hereinafter, the photoradical polymerization initiator will be described.
When ultraviolet rays and visible rays are used as the active energy rays, the active energy ray-curable composition of the present invention preferably further contains a photoradical polymerization initiator from the viewpoint of easiness of curing and cost.
When an electron beam is used as the active energy ray, the active energy ray-curable adhesive composition of the present invention can be cured without containing a photoradical polymerization initiator, but the curability is improved. Therefore, it can be contained in a small amount if necessary.

Specific examples of the photoradical polymerization initiator include benzyl dimethyl ketal, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- [4- (2-hydroxyethoxy). Phenyl] -2-hydroxy-2-methyl-1-propane-1-one, oligo [2-hydroxy-2-methyl-1- [4-1- (methylvinyl) phenyl] propanone, 2-hydroxy-1- {4- [4- (2-Hydroxy-2-methyl-propionyl) benzyl] phenyl} -2-methylpropan-1-one, 2-methyl-1- [4- (methylthio)] phenyl] -2-morpho Renopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butane-1-one, 2-dimethylamino-2- (4-methylbenzyl) -1- (4-) Acetphenone compounds such as morpholin-4-yl-phenyl) butane-1-one and 3,6-bis (2-methyl-2-morpholinopropionyl) -9-n-octylcarbazole;
Benzoin compounds such as benzoin, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether;
Benzophenone, 2-methylbenzophenone, 3-methylbenzophenone, 4-methylbenzophenone, 2,4,6-trimethylbenzophenone, 4-phenylbenzophenone, methyl-2-benzophenone, 1- [4- (4-benzoylphenyl sulfanyl) phenyl ] -2-Methyl-2- (4-methylphenylsulfonyl) propan-1-one, 4,4'-bis (dimethylamino) benzophenone, 4,4'-bis (diethylamino) benzophenone and 4-methoxy-4' -Benzophenone compounds such as dimethylaminobenzophenone;
Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, etc. Acylphosphine oxide compounds; as well as thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, isopropylthioxanthone, 1-chloro-4-propylthioxanthone, 3- [3,4-dimethyl-9-oxo-9H-thioxanthone-2 -Il-oxy] -2-hydroxypropyl-N, N, N-trimethylammonium chloride, fluorothioxanthone and other thioxanthone compounds can be mentioned.
Examples of compounds other than the above include benzyl, ethyl (2,4,6-trimethylbenzoyl) phenylphosphinate, methyl phenylglioxyate, ethyl anthraquinone, phenanthrenequinone, camphorquinone and the like.

Among these compounds, the photoradical polymerization initiator preferably contains an acylphosphine oxide compound because the composition is excellent in curability and the cured product is excellent in low yellowing.

When it is necessary to increase the thickness of the cured product, for example, when it is necessary to make it 50 μm or more, for the purpose of improving the curability inside the cured product, or when an ultraviolet absorber or pigment is used in combination. For the purpose of improving the curability of the composition, it is preferable to use a plurality of kinds of compounds selected from an acylphosphine oxide compound, a thioxanthone compound and an α-aminoalkylphenone compound in combination.
Preferred examples of the compound in this case include bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and ethyl- (2,6-trimethylbenzoyl) as the acylphosphine oxide compound. 4,6-trimethylbenzoyl) phenylphosphinate and bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide and the like can be mentioned. Examples of the thioxanthone compound include 2,4-diethylthioxanthone. , Isopropylthioxanthone, 1-chloro-4-propoxythioxanthone and the like, and examples of the α-aminoalkylphenone compound include 2-methyl-1- [4- (methylthio)] phenyl] -2-morpholinopropane. -1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butane-1-one, 2-dimethylamino-2- (4-methylbenzyl) -1- (4-morpholin-) 4-Il-phenyl) -butane-1-one and the like can be mentioned.

As the photoradical polymerization initiator, only one of the exemplified compounds may be used, or two or more of them may be used in combination.

The content ratio of the photoradical polymerization initiator is preferably 0.1 to 15 parts by mass, more preferably 0.5 to 10 parts by mass, based on 100 parts by mass of the total amount of the curable components. By setting the ratio of the photoradical polymerization initiator to 0.1 parts by mass or more, the photocurability of the composition can be improved, and by setting the ratio to 15 parts by mass or less, the internal curability of the cured product is good. Can be.

4. Method of using the active energy ray-curable composition As the method of using the active energy ray-curable composition of the present invention, a conventional method may be followed, and after the composition is applied to the release-treated substrate, the composition is applied. Alternatively, a cured product can be obtained by pouring the composition into a mold that has been demolded and then irradiating it with active energy rays.

The coating thickness of the active energy ray-curable composition of the present invention may be selected according to the substrate to be used and the intended use.

Examples of the active energy ray include visible light, ultraviolet light, X-ray, electron beam, and the like, but ultraviolet light is preferable because an inexpensive device can be used.

As the light source for curing by ultraviolet rays, various light sources can be used, and examples thereof include black lights, high-pressure mercury lamps, metal halide lamps, xenon lamps, electrodeless discharge lamps, carbon arc lamps, and LEDs. Illuminance of ultraviolet rays, in the range of UV-A (365 nm vicinity) is preferably ^{0.1~1,000mW / cm 2, 0.5~500mW / cm} 2 is more preferable. The dose of ultraviolet rays is in the range of UV-A (365 nm vicinity) is preferably ^{200~30,000mJ / cm 2, 500~10,000mJ / cm} 2 is more preferable.

When curing by an electron beam, various devices can be used as the EB irradiation device that can be used, and examples thereof include Cockcroft-Walton type, Van de Graaff type, and resonance transformer type devices.
The absorbed dose of the electron beam is preferably 1 to 200 kGy, more preferably 10 to 100 kGy.
The acceleration voltage of the electron beam may be appropriately set in the range of 80 to 300 kV.
The oxygen concentration in the electron beam irradiation atmosphere is preferably 500 ppm or less, more preferably 300 ppm or less.

Since the obtained cured product has excellent elongation and tensile strength, for example, packings, gaskets, hose materials, etc. for automobile parts, electrical appliances, medical products, etc., packaging materials, civil engineering and construction materials, electric wires, miscellaneous goods, etc. It can be suitably used for applications such as materials in a wide range of fields such as.

Hereinafter, the present invention will be specifically described based on Examples. The present invention is not limited to these examples. In the following, "parts" and "%" mean parts by mass and% by mass unless otherwise specified.
The method for analyzing the polymer obtained in the production example will be described below.

<Molecular weight measurement>
The obtained polymer was subjected to gel permeation chromatography (GPC) measurement under the conditions described below to obtain a number average molecular weight (Mn) and a weight average molecular weight (Mw) in terms of polystyrene. Moreover, the molecular weight distribution (Mw / Mn) was calculated from the obtained values.
○ Measurement conditions Column: Tosoh TSKgel SuperMultipore HZ-M x 4 Solvent: Tetrahydrofuran Temperature: 40 ° C
Detector: RI
Flow velocity: 600 μL / min

Next, the evaluation method of the cured product in Examples and Comparative Examples will be described below.
<Physical characteristics>
The cured products obtained in Examples and Comparative Examples were measured for breaking elongation [EL (%)] and breaking strength [Ts (MPa)] under normal conditions (25 ° C.) in accordance with JIS K 6251.
In addition, the tensile product was calculated as follows.
Tension product = elongation at break [EL (%)] x strength at break [Ts (MPa)]

1. 1. Synthesis example << Synthesis of RAFT agent >>
Synthesis example 1
(Synthesis of 1,4-bis (n-dodecylsulfanylthiocarbonylsulfanylmethyl) benzene)
1-Dodecanethiol (42.2 g), 20% KOH aqueous solution (63.8 g), and trioctylmethylammonium chloride (1.5 g) were added to a eggplant-shaped flask, cooled in an ice bath, and carbon disulfide (15.9 g) was added. ) And tetrahydrofuran (hereinafter also referred to as "THF") (38 ml) were added, and the mixture was stirred for 20 minutes. A THF solution (170 ml) of α, α'-dichloro-p-xylene (16.6 g) was added dropwise over 30 minutes. After reacting at room temperature for 1 hour, the mixture was extracted from chloroform, washed with pure water, dried over anhydrous sodium sulfate, and concentrated on a rotary evaporator. The obtained crude product is purified by column chromatography and then recrystallized from ethyl acetate to form 1,4-bis (n-dodecylsulfanylthiocarbonylsulfanylmethyl) benzene represented by the following formula (5). (Hereinafter, also referred to as “DLBTTC”) was obtained in a yield of 80%. ¹ The peak of the target product was confirmed at 7.2 ppm, 4.6 ppm, and 3.4 ppm by 1 H-NMR measurement.

≪（Ｂ）成分の合成≫

≪Synthesis of (B) component≫

Synthesis example 2
Dicyclopentadiene was placed in a 100 ml two-necked flask equipped with a thermometer, a Wigrew fractional tube, a distilling head, a Liebig condenser, and a 50 ml eggplant-shaped flask. Cyclopentadiene was obtained by slowly raising the temperature of the oil bath until cyclopentadiene (bp: 41 ° C.) was distilled off by decomposition so that the internal temperature became 140 ° C.
1,6-Hexanediol acrylate was placed in a 100 ml 4-neck flask, and cyclopentadiene was slowly added dropwise under a 5% ON flow. At the time of dropping, the dropping speed was adjusted so that the internal temperature was 90 ° C. or lower, and after the dropping was completed, stirring was continued at the internal temperature of 90 ° C. for 2 hours. By distilling off unreacted cyclopentadiene, a dinorbornene compound (DiNB) represented by the following formula (6) was synthesized.

Synthesis example 3
The 1,6-hexanediol acrylate of Synthesis Example 2 was changed to pentaerythritol tetraacrylate, and the tetranorbornene compound (TertaNB) represented by the following formula (7) was synthesized by the same operation.

2. Manufacturing example
Manufacturing example 1
(Production of Polymer A-SH)
DLBTTC (1.93 g), azobisisobutyronitrile (hereinafter also referred to as "AIBN") (0.079 g), butyl acrylate (75.2 g) and anisole (74.) in a 100 mL flask equipped with a stirrer and a thermometer. 0 g) was charged, sufficiently degassed by nitrogen bubbling, and polymerization was started in a constant temperature bath at 70 ° C. After 4 hours, the reaction was stopped by cooling to room temperature. The above polymerization solution was reprecipitated and purified from methanol and vacuum dried to obtain a polymer A. When the amount of residual monomer was quantified from the GC measurement and the polymerization rate was calculated, it was 87.2%. The molecular weight of the obtained polymer A was Mn24,400, Mw27,300, and Mw / Mn1.12 as measured by GPC (gel permeation chromatography) (in terms of polystyrene).
Next, in a 300 mL flask equipped with a stirrer and a thermometer, the polymer A (48.1 g), tris (2-carboxyethyl) phosphine (TCEP) (0.1 g) and tetrahydrofuran (THF) (51) obtained above were placed. .4 g) was charged and sufficiently dissolved at room temperature. After sufficient degassing with nitrogen bubbling, hydrazine monohydrate (0.4 g) was added while performing nitrogen bubbling. Within minutes of the addition, the yellow-transparent solution turned colorless and transparent. After 10 minutes, the polymer A-SH was obtained by reprecipitation purification from methanol and vacuum drying.
The molecular weights of the obtained polymers A-SH were Mn24,300, Mw27,100, and Mw / Mn1.12 as measured by GPC (in terms of polystyrene). Further, when the ^{terminal SH conversion rate was determined from 1 1} H-NMR measurement, it was calculated to be 95%.

Production Example 2 and Comparative Production Examples 1 and 2
(Production of Polymers B-SH, C-SH, D-SH)
Polymers B-SH, C-SH, and D-SH were obtained by performing the same operations as in Example 1 except that the charged raw materials, the charged amount, and the polymerization conditions were changed as shown in Tables 1 and 2.

3. 3. Example
Examples 1 to 3 and Comparative Examples 1 and 2
As shown in Table 3, the polymer, the component (B), and 2,2-dimethoxy-2-phenylacetophenone (DMPA, manufactured by Tokyo Kasei) as a photoinitiator were blended (Examples 1 and 2 and Comparative Examples). 1,2: 0.5 mol of TeraNB per 1 mol of polymer. Example 3: 0.125 mol of TeraNB and 0.75 mol of DiNB per 1 mol of polymer).
This is dissolved in ethyl acetate to produce an active energy ray-curable composition, which is then poured into a mold so that the thickness after drying is 2 mm, ethyl acetate is dried and distilled off, and then the conditions shown below are met. A cured product having a thickness of 2 mm was obtained by irradiating with light. The tensile properties of the obtained cured product were evaluated, and the results are shown in Table 3.
○ Light irradiation conditions Light source: Black light Illuminance: 0.9 mW / cm ² (365 nm) (Measured value of UIT-250 manufactured by Ushio, Inc.)
Atmosphere: Under air atmosphere Irradiation time: After irradiating the air side for 30 minutes, the opposite side was irradiated for 30 minutes.
Curing temperature: Room temperature (23 ° C)

Example 4
As shown in Table 3, the polymer B-SH, acryloyl morpholine (ACMO) and DMPA were blended and poured into a mold having a depth of 2 mm. By irradiating this with light under the same conditions as in Examples 1 to 3, a cured product having a thickness of 2 mm was obtained. The obtained cured product is a triblock copolymer (ACMO chain-vinyl polymer (A) -ACMO chain), and its molecular weight is Mn29,000, Mw37,700, Mw according to GPC measurement (polystyrene conversion). It was /Mn1.30. In addition, the tensile properties of the obtained cured product were evaluated, and the results are shown in Table 3.

As is clear from the results of Examples 1 to 4, the active energy ray-curable composition of the present invention was excellent in elongation and tensile strength of the cured product.
On the other hand, the active energy ray-curable composition (Comparative Examples 1 and 2) having two or more mercapto groups at the terminal and containing a vinyl polymer having a number average molecular weight of less than 20,000 is cured thereof. The growth rate and tension of the product were inferior.

The active energy ray-curable composition of the present invention is a material in a wide range of fields such as packings, gaskets or hose materials for automobile parts, electrical appliances and medical-related products, packaging materials, civil engineering and construction materials, electric wires, miscellaneous goods and the like. It can be used in various fields such as.

Claims (9)

Active energy ray curing containing a vinyl polymer (A) having two or more mercapto groups at the terminal and a number average molecular weight of 20,000 to 200,000 and an ethylenically unsaturated group-containing compound (B). Mold composition. The active energy ray-curable composition according to claim 1, wherein the vinyl-based polymer (A) contains a (meth) acrylic acid alkyl ester compound having an alkyl group having 1 to 12 carbon atoms as a main constituent monomer. Stuff. Claim 1 or claim 1, wherein the ethylenically unsaturated group-containing compound (B) contains at least one selected from the group consisting of a (meth) allyl group-containing compound, a vinyl group-containing compound and a (meth) acryloyl group-containing compound. 2. The active energy ray-curable composition according to 2. A method for producing an active energy ray-curable composition.
(1) A vinyl-based monomer is polymerized using a polymerization control agent having two or more thiocarbonylthio groups to have two or more thiocarbonylthio groups at the terminals and a number average molecular weight of 20. A step of obtaining a polymer (P1) of 000 to 200,000,
(2) A nucleophile is reacted with the polymer (P1) obtained in the step (1) to have two or more mercapto groups at the terminals and a number average molecular weight of 20,000 to 200,000. The step of obtaining the vinyl-based polymer (A), which is
(3) A production method comprising a step of mixing the vinyl-based polymer (A) obtained in the step (2) and the ethylenically unsaturated group-containing compound (B). The polymerization control agent having two or more thiocarbonylthio groups has two or more formulas (1a) in the molecule.

^(Wherein, Z is a group represented by ^{-R A, -SR A, -OR A} , or ^-NR A ^{R B, R A} and ^{R B} are the same or different, have a substituent Indicates an alkyl group which may have an alkyl group, an aryl group which may have a substituent, a heteroaryl group which may have a substituent, or an aralkyl group which may have a substituent. Z is -NR. when the group represented by ^a R ^B, R ^a and R ^B may form a ring together with the adjacent nitrogen atom bonded to each other, the ring may have a substituent.)
The production method according to claim 4, which is a RAFT agent having a group represented by. The RAFT agent is based on the formula (1):

(In the formula, R represents an n-valent organic group which may have one or more heteroatoms selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom, and n is an integer of two or more. And Z is the same as above.)
The production method according to claim 5, which is a compound represented by the above or a salt thereof. The production method according to any one of claims 4 to 6, wherein the main component of the vinyl-based monomer is a (meth) acrylic acid alkyl ester compound having an alkyl group having 1 to 12 carbon atoms. 4. To claim 4, wherein the ethylenically unsaturated group-containing compound (B) contains at least one selected from the group consisting of a (meth) allyl group-containing compound, a vinyl group-containing compound, and a (meth) acryloyl group-containing compound. The production method according to any one of 7. A method for producing a cured product, which comprises a step of curing the active energy ray-curable composition obtained by the production method according to any one of claims 4 to 8.