JP7547733B2 - Undercoating agents, cured products and laminates - Google Patents

Description

This disclosure relates to undercoating agents, cured products, and laminates.

A known method for producing a film is to apply an undercoat agent to the surface of a substrate to provide an undercoat layer. Various undercoat agents have been developed depending on the type of substrate.

Patent Document 1 (JP Patent Publication No. 2011-195835) discloses an undercoat agent containing a polyaziridine compound.

JP 2011-195835 A

The above-mentioned undercoat agent is for producing an undercoat layer to be provided between an inorganic thin film and a substrate. In recent years, there has been a demand for an undercoat agent for producing an undercoat layer to be provided between an active energy ray-curable resin and a substrate.

The problem that the present invention aims to solve is to provide an undercoat agent that has good drying properties for the cured product, good adhesion between the cured product and an active energy ray-curable resin, and good adhesion between the cured product and a substrate, and that provides a good appearance for the laminate when it is produced.

After extensive research, the inventors discovered that the above problems can be solved by using a specific ingredient.

The present disclosure provides the following:
(Item 1)
Hydroxyl-containing (meth)acrylic polymer (A), and hydroxyl-containing poly(meth)acrylate (B)
An undercoating agent comprising:
(Item 2)
The undercoating agent according to the above item, wherein the hydroxyl group-containing poly(meth)acrylate (B) is a hydroxyl group-containing polymer poly(meth)acrylate.
(Item 3)
A cured product of the undercoat agent according to any one of the above items.
(Item 4)
A laminate comprising a film and a cured undercoat agent layer comprising the cured undercoat agent described above laminated on at least one surface of the film.
(Item 5)
The laminate according to the above item, wherein an active energy ray-curable resin cured product layer is laminated on the undercoat agent cured product layer.

In the present disclosure, one or more of the features described above may be provided in further combinations in addition to the combinations explicitly stated.

The above undercoat agent has excellent drying properties, and the cured product has excellent adhesion to active energy ray-curable resins, interlayer adhesion to the substrate, and appearance.

Throughout this disclosure, the range of the values of the physical properties, contents, etc. may be set as appropriate (for example, by selecting from the upper and lower limit values described in each item below). Specifically, when A1, A2, A3, A4 (A1>A2>A3>A4) are exemplified as the upper and lower limits of the value α, the range of the value α is exemplified as A1 or less, A2 or less, A3 or less, A2 or more, A3 or more, A4 or more, A1 to A2, A1 to A3, A1 to A4, A2 to A3, A2 to A4, A3 to A4, etc.

[Undercoat agent]
The present disclosure provides an undercoating agent comprising a hydroxyl group-containing (meth)acrylic polymer (A) and a hydroxyl group-containing poly(meth)acrylate (B).

<Hydroxyl Group-Containing (Meth)Acrylic Polymer (A): Also Referred to as Component (A)>
The component (A) may be used alone or in combination of two or more types.

Examples of component (A) include copolymers containing structural units derived from non-hydroxyl group-containing alkyl (meth)acrylates and structural units derived from hydroxyl group-containing alkyl (meth)acrylates.

In this disclosure, "(meth)acrylic" means "at least one selected from the group consisting of acrylic and methacrylic." Similarly, "(meth)acrylate" means "at least one selected from the group consisting of acrylate and methacrylate." Furthermore, "(meth)acryloyl" means "at least one selected from the group consisting of acryloyl and methacryloyl."

(Non-Hydroxyl Group-Containing Alkyl (Meth)acrylate: Also Known as Component (a1))
The non-hydroxyl group-containing alkyl (meth)acrylate is
(In the formula, R ^a1 is a hydrogen atom or a methyl group, and R ^a2 is an alkyl group.)
The non-hydroxyl group-containing alkyl (meth)acrylates may be used alone or in combination of two or more.

Examples of alkyl groups include linear alkyl groups, branched alkyl groups, and cycloalkyl groups.

A straight chain alkyl group is represented by the general formula -C _n H _2n+1 (n is an integer of 1 or more). Examples of the straight chain alkyl group include a methyl group, an ethyl group, a n-propyl group, a n -butyl group, a n-pentyl group, a n-hexyl group, a n-heptyl group, a n-octyl group, a n-nonyl group, and a n-decamethyl group.

A branched alkyl group is a linear alkyl group in which at least one hydrogen atom is replaced by an alkyl group. Examples of branched alkyl groups include diethylpentyl, trimethylbutyl, trimethylpentyl, and trimethylhexyl.

Examples of cycloalkyl groups include monocyclic cycloalkyl groups, bridged cycloalkyl groups, and condensed cycloalkyl groups.

In this disclosure, a monocyclic ring refers to a ring structure formed by covalent carbon bonds that does not have an internal bridge structure. A fused ring refers to a ring structure in which two or more monocyclic rings share two atoms (i.e., each ring shares (fused) one side with the other). A bridged ring refers to a ring structure in which two or more monocyclic rings share three or more atoms.

Examples of monocyclic cycloalkyl groups include cyclopentyl, cyclohexyl, cycloheptyl, cyclodecyl, and 3,5,5-trimethylcyclohexyl groups.

Examples of bridged ring cycloalkyl groups include tricyclodecyl, adamantyl, and norbornyl groups.

Examples of condensed ring cycloalkyl groups include bicyclodecyl groups.

Examples of non-hydroxyl group-containing alkyl (meth)acrylates include non-hydroxyl group-containing linear alkyl (meth)acrylates, non-hydroxyl group-containing branched alkyl (meth)acrylates, and non-hydroxyl group-containing cycloalkyl (meth)acrylates.

Examples of non-hydroxyl group-containing linear alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, n-butyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, n-hexadecyl (meth)acrylate, n-dodecyl (meth)acrylate, n-octadecyl (meth)acrylate, n-icosyl (meth)acrylate, and n-docosyl (meth)acrylate.

Examples of non-hydroxyl group-containing branched alkyl (meth)acrylates include isopropyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate.

Examples of hydroxyl group-free cycloalkyl (meth)acrylates include cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cyclopentanyl (meth)acrylate, and isobornyl (meth)acrylate.

Among these, non-hydroxyl group-containing alkyl (meth)acrylates in which the alkyl group has about 1 to 20 carbon atoms are preferred because they contribute to the leveling and adhesion properties of the undercoat agent. In addition, by using non-hydroxyl group-containing alkyl (meth)acrylates in which the alkyl group has a different number of carbon atoms, it is possible to adjust the physical properties of component (A), such as the glass transition temperature.

The upper and lower limits of the content of the non-hydroxyl group-containing alkyl (meth)acrylate-derived structural units in 100 mol % of all structural units of component (A) are, for example, 98, 95, 90, 85, 80, 75, 70, 65, and 62 mol %. In one embodiment, the content is preferably 62 to 98 mol %.

The upper and lower limits of the content of the non-hydroxyl group-containing alkyl (meth)acrylate-derived structural units relative to 100% by mass of all structural units of component (A) are, for example, 98, 95, 90, 85, 80, 75, 70, and 65% by mass. In one embodiment, the content is preferably 65 to 98% by mass.

(Hydroxyl-containing alkyl (meth)acrylate: also referred to as component (a2))
The hydroxyl group-containing alkyl (meth)acrylate has the following structural formula:
(In the formula, R ^a3 is a hydrogen atom or a methyl group, and R ^a4 is a linear alkylene group, a branched alkylene group, or a cycloalkylene group.)
The hydroxyl group-containing alkyl (meth)acrylates may be used alone or in combination of two or more.

A straight-chain alkylene group is represented by the general formula: -(CH ₂ ) _n - (n is an integer of 1 or more). Examples of the straight-chain alkylene group include a methylene group, an ethylene group, a propylene group, an n-butylene group, an n-pentylene group, an n-hexylene group, an n-heptylene group, an n-octylene group, an n-nonylene group, and an n-decamethylene group.

A branched alkylene group is a linear alkylene group in which at least one hydrogen atom is replaced by an alkyl group. Examples of branched alkylene groups include a diethylpentylene group, a trimethylbutylene group, a trimethylpentylene group, and a trimethylhexylene group (trimethylhexamethylene group).

Examples of cycloalkylene groups include monocyclic cycloalkylene groups, bridged ring cycloalkylene groups, and condensed ring cycloalkylene groups. In addition, one or more hydrogen atoms of the cycloalkylene group may be substituted with a straight-chain or branched alkyl group.

Examples of monocyclic cycloalkylene groups include cyclopentylene, cyclohexylene, cycloheptylene, cyclodecylene, and 3,5,5-trimethylcyclohexylene groups.

Examples of bridged ring cycloalkylene groups include tricyclodecylene groups, adamantylene groups, and norbornylene groups.

Examples of condensed ring cycloalkylene groups include bicyclodecylene groups.

Examples of hydroxyl group-containing alkyl (meth)acrylates include hydroxyl group-containing linear alkyl (meth)acrylates, hydroxyl group-containing branched alkyl (meth)acrylates, and hydroxyl group-containing cycloalkyl (meth)acrylates.

Examples of hydroxyl group-containing linear alkyl (meth)acrylates include hydroxymethyl (meth)acrylate, hydroxyethyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate.

Examples of hydroxyl group-containing branched alkyl (meth)acrylates include 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 3-hydroxybutyl (meth)acrylate.

Examples of hydroxyl group-containing cycloalkyl (meth)acrylates include hydroxycyclohexyl (meth)acrylate and 4-(hydroxymethyl)cyclohexylmethyl (meth)acrylate.

The upper and lower limits of the content of the structural units derived from hydroxyl group-containing alkyl (meth)acrylate in 100 mol % of all structural units of component (A) are, for example, 38, 35, 30, 25, 20, 15, 10, 5, 2.5, 2, and 1.5 mol %. In one embodiment, the content is preferably 1.5 to 38 mol %.

The upper and lower limits of the content of the structural units derived from hydroxyl group-containing alkyl (meth)acrylates relative to 100% by mass of all structural units of component (A) are, for example, 35, 30, 25, 20, 15, 10, 5, 2.5, and 2% by mass. In one embodiment, the content is preferably 2 to 35% by mass.

The upper and lower limits of the molar ratio of the structural units derived from a non-hydroxyl group-containing alkyl (meth)acrylate to the structural units derived from a hydroxyl group-containing alkyl (meth)acrylate in the component (A) ( _mol non-hydroxyl group-containing alkyl (meth)acrylate / _mol hydroxyl group-containing alkyl (meth)acrylate) are, for example, 57, 50, 40, 30, 20, 10, 5, 2, 1.6, etc. In one embodiment, the molar ratio is preferably 1.6 to 57.

The upper and lower limits of the mass ratio of the structural units derived from a non-hydroxyl group-containing alkyl (meth)acrylate to the structural units derived from a hydroxyl group-containing alkyl (meth)acrylate in the component (A) (non-hydroxyl group-containing alkyl (meth)acrylate _mass / hydroxyl group-containing alkyl (meth)acrylate _mass ) are, for example, 49, 40, 30, 20, 10, 5, 2, 1.8, etc. In one embodiment, the mass ratio is preferably 1.8 to 49.

(Monomer (a3) other than components (a1) and (a2): also referred to as component (a3))
When producing the (A) component, a monomer (a3) that does not fall under either the (a1) component or the (a2) component may be used. The (a3) component may be used alone or in combination of two or more. When the (a3) component is used when producing the (A) component, the (A) component is incorporated into the polymer as a structural unit derived from the (a3) component.

Examples of component (a3) include α,β-unsaturated carboxylic acids, epoxy group-containing (meth)acrylates, styrenes, α-olefins, unsaturated alcohols, aryl (meth)acrylates, dialkylaminoalkyl (meth)acrylates, (meth)acrylonitrile, (meth)acrylamide group-containing compounds, di(meth)acrylic esters, divinyl esters, trifunctional monomers, and tetrafunctional monomers.

Examples of α,β-unsaturated carboxylic acids include (meth)acrylic acid, maleic acid, crotonic acid, fumaric acid, and itaconic acid.

Examples of epoxy group-containing (meth)acrylates include glycidyl (meth)acrylate and β-methylglycidyl (meth)acrylate.

Examples of styrenes include styrene, α-methylstyrene, and t-butylstyrene.

Examples of α-olefins include 2,4,4-trimethyl-1-pentene, 3-methyl-1-butene, 3-methyl-1-pentene, and 1-hexene.

Examples of unsaturated alcohols include (meth)allyl alcohol, 4-penten-1-ol, 1-methyl-3-buten-1-ol, and 5-hexen-1-ol.

Examples of aryl (meth)acrylates include phenyl (meth)acrylate, benzyl (meth)acrylate, and 4-methylbenzyl (meth)acrylate.

Examples of dialkylaminoalkyl (meth)acrylates include dimethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminopropyl (meth)acrylate, diethylaminopropyl (meth)acrylate, etc.

Examples of (meth)acrylamide group-containing compounds include (meth)acrylamide, (meth)acrylamides such as N-methylol (meth)acrylamide, N,N-dimethyl (meth)acrylamide, diacetone (meth)acrylamide, isopropyl (meth)acrylamide, 2-(meth)acrylamide-2-methylpropanesulfonic acid, 2-(meth)acrylamide-2-methylpropanecarboxylic acid, methylene bis(meth)acrylamide, ethylene bis(meth)acrylamide, hexamethylene bis(meth)acrylamide, dimethylaminoethyl (meth)acrylamide, diethylaminoethyl (meth)acrylamide, dimethylaminopropyl (meth)acrylamide, diethylaminopropyl (meth)acrylamide, etc.

Examples of di(meth)acrylic esters include ethylene glycol di(meth)acrylic ester and diethylene glycol di(meth)acrylic ester.

Examples of divinyl esters include divinyl adipate and divinyl sebacate.

Examples of trifunctional monomers include 1,3,5-triacryloylhexahydro-S-triazine, triallyl isocyanurate, triallylamine, triallyl trimellitate, and N,N-diallylacrylamide.

Examples of tetrafunctional monomers include tetramethylolmethane tetraacrylate, tetraallyl pyromellitate, and N,N,N',N'-tetraallyl-1,4-diaminobutane.

The upper and lower limits of the content of the structural units derived from component (a3) relative to 100 mol % of all structural units of component (A) are, for example, 13, 10, 9, 5, 4, 1, and 0 mol %. In one embodiment, the content is preferably 0 to 13 mol %.

The upper and lower limits of the content of the structural units derived from component (a3) relative to 100% by mass of all structural units of component (A) are, for example, 10, 9, 5, 4, 1, and 0% by mass. In one embodiment, the content is preferably 0 to 10% by mass.

Examples of upper and lower limits for the molar ratio ((a3) _mol /(a1) _mol ) of the structural units derived from the component (a1) to the structural units derived from the component (a3) in the component (A) are 0.22, 0.20, 0.15, 0.10, 0.05, and 0. In one embodiment, the above molar ratio is preferably 0 to 0.22.

The upper and lower limits of the mass ratio ((a3) _mass /(a1) _mass ) of the structural units derived from ...

The upper and lower limits of the molar ratio ((a3) _mol /(a2) _mol ) of the structural units derived from the component (a2) to the structural units derived from the component (a3) in the component (A) are, for example, 8, 7, 6, 5, 4, 3, 2, 1, 0.5, and 0. In one embodiment, the molar ratio is preferably 0 to 8.

The upper and lower limits of the mass ratio ((a3) _mass /(a2) _mass ) of the structural units derived from ...

<Physical properties of component (A)>
Examples of upper and lower limits of the glass transition temperature of component (A) are 100, 90, 88, 85, 80, 70, 60, 50, 40, 35, and 20° C. In one embodiment, the glass transition temperature of component (A) is preferably 20 to 100° C., and more preferably 40 to 90° C.

The glass transition temperature is measured under appropriate conditions (heating rate: 10°C/min) using a commercially available differential scanning calorimeter (e.g., product name "DSC8230B", manufactured by Rigaku Corporation).

The upper and lower limits of the hydroxyl value (solid content equivalent) of component (A) are 150, 140, 130, 120, 110, 100, 90, 80, 70, 60, 50, 48, 45, 40, 30, 20, 15, and 10 mgKOH/g, for example. In one embodiment, the hydroxyl value (solid content equivalent) of component (A) is preferably 10 to 150 mgKOH/g, and more preferably 30 to 100 mgKOH/g.

In this disclosure, the hydroxyl value is measured, for example, by a method conforming to JIS K1557-1.

Examples of the upper and lower limits of the hydroxyl equivalent of component (A) are 5611, 5500, 5000, 4500, 4000, 3500, 3000, 2500, 2000, 1500, 1000, 500, 400, and 370 g/eq. In one embodiment, the hydroxyl equivalent of component (A) is preferably 370 to 5611 g/eq.

In this disclosure, hydroxyl equivalent weight means the calculated mass per mole of hydroxyl groups (g/eq).

Examples of the upper and lower limits of the acid value of component (A) are 0.4, 0.3, 0.2, 0.18, 0.1, 0.09, 0.05, and 0.04 mgKOH/g. In one embodiment, the acid value of component (A) is preferably about 0.04 to 0.4 mgKOH/g, and more preferably 0.09 to 0.18 mgKOH/g, particularly taking into account curability.

In this disclosure, the acid value is measured, for example, by a method conforming to JIS K0070.

Examples of upper and lower limits of the weight average molecular weight (Mw) of component (A) include 100,000, 90,000, 80,000, 70,000, 60,000, 50,000, 40,000, 30,000, 20,000, 10,000, 5,000, 4,000, and 3,000. In one embodiment, the weight average molecular weight (Mw) of component (A) is preferably 3,000 to 100,000, and more preferably 10,000 to 80,000.

Examples of the upper and lower limits of the number average molecular weight (Mn) of component (A) include 100,000, 90,000, 80,000, 70,000, 60,000, 50,000, 40,000, 30,000, 20,000, 10,000, 5,000, 4,000, and 3,000. In one embodiment, the number average molecular weight (Mn) of component (A) is preferably 3,000 to 100,000, and more preferably 10,000 to 80,000.

The weight average molecular weight and number average molecular weight are measured using a commercially available gel permeation chromatography instrument (e.g., product name "HLC-8220GPC", manufactured by Tosoh Corporation).

The upper and lower limits of the molecular weight distribution (Mw/Mn) of component (A) are, for example, 10, 7.5, 5, 2.5, 2, and 1.5. In one embodiment, the molecular weight distribution (Mw/Mn) of component (A) is preferably 1.5 to 10.

Component (A) can be produced by various known methods. Examples of methods for producing component (A) include a method in which components (a1) and (a2), and optionally component (a3), are copolymerized in the presence of a polymerization initiator at about 80 to 180°C for about 1 to 10 hours without a solvent or in an organic solvent. Examples of organic solvents and polymerization initiators used in producing component (A) include those described below.

Examples of upper and lower limits for the content of component (A) in the undercoating agent include 88, 85, 80, 70, 60, 50, 40, 30, 20, 10, 5, and 3% by mass. In one embodiment, the content is preferably 3 to 88% by mass.

<Hydroxyl Group-Containing Poly(meth)acrylate (B): Also referred to as Component (B)>
The component (B) may be used alone or in combination of two or more kinds.

In this disclosure, "hydroxyl-containing poly(meth)acrylate" means a compound having one or more hydroxyl groups and two or more (meth)acryloyl groups.

Examples of hydroxyl group-containing poly(meth)acrylates include hydroxyl group-containing polymer poly(meth)acrylates and hydroxyl group-containing oligomer poly(meth)acrylates.

(Hydroxyl Group-Containing Polymer Poly(meth)acrylate)
In the present disclosure, "hydroxyl-containing polymer poly(meth)acrylate" means a polymer having one or more hydroxyl groups and two or more (meth)acryloyl groups.

Hydroxyl group-containing polymer poly(meth)acrylate can be produced using known methods. An example of a method for producing polymer poly(meth)acrylate is a method in which an epoxy group-containing (meth)acrylic polymer is reacted with an α,β-unsaturated carboxylic acid.

Examples of upper and lower limits of the content of epoxy group-containing (meth)acrylate-derived structural units in 100 mol % of all structural units of the epoxy group-containing (meth)acrylic polymer include 100, 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, and 7 mol %. In one embodiment, the content is preferably 7 to 100 mol %.

The upper and lower limits of the content of epoxy group-containing (meth)acrylate-derived structural units in 100% by mass of all structural units of the epoxy group-containing (meth)acrylic polymer are 100, 95, 90, 85, 80, 75, 70, 65, 62, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10% by mass, etc. In one embodiment, the content is preferably 10 to 100% by mass.

Examples of upper and lower limits for the content of non-hydroxyl group-containing alkyl (meth)acrylate-derived structural units in 100 mol % of all structural units of the epoxy group-containing (meth)acrylic polymer include 93, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, 5, and 0 mol %. In one embodiment, the content is preferably 0 to 93 mol %.

Examples of upper and lower limits for the content of structural units derived from non-hydroxyl group-containing alkyl (meth)acrylates in 100% by mass of all structural units of the epoxy group-containing (meth)acrylic polymer include 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 38, 35, 30, 25, 20, 15, 10, 5, and 0% by mass. In one embodiment, the content is preferably 0 to 90% by mass.

The upper and lower limits of the amount of α,β-unsaturated carboxylic acid to be reacted with 100 mol% of the structural units derived from the epoxy group-containing (meth)acrylate are 100, 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, and 10 mol%, for example. In one embodiment, the amount is preferably 10 to 100 mol%.

The upper and lower limits of the amount of α,β-unsaturated carboxylic acid to be reacted with respect to 100% by mass of the structural units derived from the epoxy group-containing (meth)acrylate are, for example, 50, 45, 40, 35, 30, 25, 20, 15, 10, and 5% by mass. In one embodiment, the amount is preferably 5 to 50% by mass.

Epoxy group-containing (meth)acrylic polymers can be produced using known radical polymerization methods.

(Hydroxyl-containing oligomeric poly(meth)acrylate)
Examples of hydroxyl-containing oligomeric poly(meth)acrylates include hydroxyl-containing (poly)pentaerythritol poly(meth)acrylate, hydroxyl-containing (poly)trimethylolpropane poly(meth)acrylate, and hydroxyl-containing glycerin di(meth)acrylate.

(Hydroxyl-containing (poly)pentaerythritol poly(meth)acrylate)
The hydroxyl group-containing (poly)pentaerythritol poly(meth)acrylate has the structural formula (1):
(In the formula, m is an integer of 0 or more, R ^b1 to R ^b6 are each independently a hydrogen atom or a (meth)acryloyl group, and at least two of R ^b1 to R ^b6 are (meth)acryloyl groups and at least one of R ^b1 to R ^b6 is a hydrogen atom. Note that R ^b3 and R ^b5 may be different groups for each structural unit.)
It is a compound represented by the formula:

In this disclosure, "(poly)pentaerythritol poly(meth)acrylate" means "at least one selected from the group consisting of pentaerythritol poly(meth)acrylate and polypentaerythritol poly(meth)acrylate."

In addition, the phrase "the groups may be different for each structural unit" means, for example, when m is 2 in structural formula (1),
This means that R ^b3A and R ^b3B may be different groups, and R ^b5A and R ^b5B may be different groups (the same applies hereinafter).

Examples of hydroxyl group-containing pentaerythritol poly(meth)acrylates include pentaerythritol di(meth)acrylate and pentaerythritol tri(meth)acrylate.

Examples of hydroxyl group-containing polypentaerythritol poly(meth)acrylates include dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, tripentaerythritol di(meth)acrylate, tripentaerythritol tri(meth)acrylate, tripentaerythritol tetra(meth)acrylate, tripentaerythritol penta(meth)acrylate, tripentaerythritol hexa(meth)acrylate, and tripentaerythritol hepta(meth)acrylate.

(Hydroxyl group-containing (poly)trimethylolpropane poly(meth)acrylate)
(Poly)trimethylolpropane poly(meth)acrylate has the structural formula (2):
(In the formula, p is an integer of 0 or more, R ^b7 to R ^b10 are hydrogen atoms or (meth)acryloyl groups, and at least two of R ^b7 to R ^b10 are (meth)acryloyl groups and at least one of R ^b7 to R ^b10 is a hydrogen atom. Note that R ^b9 may be a different group for each structural unit.)
It is a compound represented by the formula:

In this disclosure, "(poly)trimethylolpropane poly(meth)acrylate" means "at least one selected from the group consisting of trimethylolpropane poly(meth)acrylate and polytrimethylolpropane poly(meth)acrylate."

Examples of hydroxyl group-containing trimethylolpropane poly(meth)acrylate include trimethylolpropane di(meth)acrylate.

Examples of hydroxyl group-containing polytrimethylol poly(meth)acrylate include ditrimethylol di(meth)acrylate and ditrimethylol tri(meth)acrylate.

(Hydroxyl-containing glycerin di(meth)acrylate)
The hydroxyl group-containing glycerin (meth)acrylate has the structural formula (3):
(In the formula, two of R ^b11 to R ^b13 are (meth)acryloyl groups, and one of R ^b11 to R ^b13 is a hydrogen atom.)
It is a compound represented by the formula:

Examples of hydroxyl group-containing glycerin (meth)acrylates include 2-hydroxy-3-(meth)acryloyloxypropyl (meth)acrylate and 1-hydroxy-2-(meth)acryloyloxypropyl (meth)acrylate.

(Physical properties of hydroxyl-containing poly(meth)acrylate (B))
Examples of the upper and lower limits of the acrylic equivalent of the hydroxyl group-containing poly(meth)acrylate are 400, 375, 360, 350, 325, 310, 305, 300, 275, 250, 225, 220, 216, and 214 g/eq. In one embodiment, the (meth)acrylic equivalent is preferably 214 to 400 g/eq, and more preferably 214 to 375 g/eq from the viewpoint of improving the heat elongation.

In this disclosure, (meth)acrylic equivalent means the calculated mass per mole of (meth)acryloyl groups (g/eq).

Examples of the upper and lower limits of the hydroxyl value of the hydroxyl group-containing poly(meth)acrylate include 300, 290, 270, 250, 225, 200, 175, 150, 130, 110, and 100 mgKOH/g. In one embodiment, the hydroxyl value of the hydroxyl group-containing poly(meth)acrylate is preferably 100 to 300 mgKOH/g, and more preferably 130 to 270 mgKOH/g.

Examples of upper and lower limits of the hydroxyl group equivalent of the hydroxyl group-containing poly(meth)acrylate include 562, 550, 500, 450, 400, 350, 300, 250, 200, and 185 g/eq. In one embodiment, the hydroxyl group equivalent is preferably 185 to 562 g/eq.

The upper and lower limits of the content of component (B) in the undercoating agent are, for example, 85, 80, 70, 60, 50, 40, 30, 20, 10, 5, and 2% by mass. In one embodiment, the content is preferably 2 to 85% by mass.

The upper and lower limits of the solid content mass ratio ((A)/(B)) of the hydroxyl group-containing poly(meth)acrylic polymer (A) to the hydroxyl group-containing poly(meth)acrylate (B) are 44, 40, 35, 30, 25, 20, 15, 10, 9, 7, 5, 4, 3, 2, 1, 0.9, 0.5, 0.3, 0.2, 0.1, 0.09, 0.05, 0.04, etc. are exemplified. In one embodiment, the solid content mass ratio is preferably 0.04 to 44.

<Photopolymerization initiator (C): also referred to as component (C)>
In one embodiment, the undercoating agent may contain a photopolymerization initiator. The component (C) may be used alone or in combination of two or more kinds.

Examples of photopolymerization initiators include photoradical polymerization initiators, photocationic polymerization initiators, and photoanionic polymerization initiators.

Examples of photoradical polymerization initiators include α-hydroxyalkylphenones, unsubstituted or substituted alkylphenones, unsubstituted or substituted benzils, unsubstituted or substituted benzophenones, acylphosphine oxides, and substituted thioxanthones.

Examples of α-hydroxyalkylphenones include 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methylpropiophenone, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (1-[4-(2-hydroxyethoxyl)-phenyl]-2-hydroxy-methylpropanone) and 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzyl)phenyl)-2-methylpropan-1-one).

Examples of unsubstituted or substituted alkylphenones include benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin ethyl ether, acetophenone, 2,2-diethoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2-phenyl-2-(p-toluenesulfonyloxy)acetophenone, benzoin, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone, 2-methyl-4'-(methylthio)-2-morpholinopropiophenone, 2-isonitrosopropiophenone, and 2,2-dimethoxy-1,2-diphenylethan-1-one.

Examples of unsubstituted or substituted benzyl include benzyl, p-anisyl, and other unsubstituted or substituted benzyls.

Examples of unsubstituted or substituted benzophenones include benzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-dichlorobenzophenone, 1,4-dibenzoylbenzene, 2-benzoylbenzoic acid, 4-benzoylbenzoic acid, and methyl 2-benzoylbenzoate.

Examples of acylphosphine oxides include 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide.

Examples of substituted thioxanthone include 2-chlorothioxanthone, 2-isopropylthioxanthone, and 2,4-diethylthioxanthone.

Other examples of photoradical polymerization initiators include lithium phenyl(2,4,6-trimethylbenzoyl)phosphinate, 2-ethylanthraquinone, 2,2'-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl-1,2'-biimidazole, 2-(1,3-benzodioxol-5-yl)-4,6-bis(trichloromethyl)-1,3,5-triazine, and phenylglyoxylic acid methyl ester.

Examples of photocationic polymerization initiators include iodonium salt polymerization initiators, sulfonium salt polymerization initiators, and diazonium salt polymerization initiators.

Iodonium salt polymerization initiators include bis(4-tert-butylphenyl)iodonium hexafluorophosphate, bis(4-fluorophenyl)iodonium trifluoromethanesulfonate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroarsenate, diphenyliodonium trifluoromethanesulfonate, 4-isopropyl-4'-methyldiphenyliodonium tetrakis(pentafluorophenyl)borate, (2-methylphenyl)(2,4,6-trimethylphenyl)iodonium trifluoromethanesulfonate, (3-methylphenyl)(2,4,6-trimethylphenyl)iodonium trifluoromethanesulfonate, and (4-methylphenyl)(2,4,6-trimethylphenyl)iodonium trifluoromethanesulfonate. Examples include (4-nitrophenyl)(2,4,6-trimethylphenyl)iodonium trifluoromethanesulfonate, (4-nitrophenyl)(phenyl)iodonium trifluoromethanesulfonate, phenyl[4-(trimethylsilyl)thiophen-3-yl]iodonium trifluoromethanesulfonate, [3-(trifluoromethyl)phenyl](2,4,6-trimethylphenyl)iodonium trifluoromethanesulfonate, [4-(trifluoromethyl)phenyl](2,4,6-trimethylphenyl)iodonium trifluoromethanesulfonate, and the like.

Examples of sulfonium salt polymerization initiators include cyclopropyldiphenylsulfonium tetrafluoroborate, dimethylphenacylsulfonium tetrafluoroborate, triphenylsulfonium tetrafluoroborate, triphenylsulfonium bromide, tri-p-tolylsulfonium hexafluorophosphate, and tri-p-tolylsulfonium trifluoromethanesulfonate.

Examples of diazonium salt polymerization initiators include 4-nitrobenzenediazonium tetrafluoroborate.

Examples of photocationic polymerization initiators other than those mentioned above include substituted 4,6-bis(trichloromethyl)-1,3,5-triazines such as 2-(3,4-dimethoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-[2-(furan-2-yl)vinyl]-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-[2-(5-methylfuran-2-yl)vinyl]-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, and 2-(4-methoxystyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine.

Examples of photoanionic polymerization initiators include cyclohexyl carbamate esters and 2-(9-oxoxanthen-2-yl)propionate salts.

Examples of cyclohexylcarbamic acid esters include 1,2-bis(4-methoxyphenyl)-2-oxoethyl cyclohexylcarbamate and 2-nitrobenzyl cyclohexylcarbamate.

Examples of 2-(9-oxoxanthen-2-yl)propionate include 1,5,7-triazabicyclo[4.4.0]dec-5-ene 2-(9-oxoxanthen-2-yl)propionic acid, 1,5-diazabicyclo[4.3.0]non-5-ene 2-(9-oxoxanthen-2-yl)propionic acid, and 1,8-diazabicyclo[5.4.0]undec-7-ene 2-(9-oxoxanthen-2-yl)propionic acid.

Other examples of photoanionic polymerization initiators include acetophenone O-benzoyloxime, nifedipine, etc.

Examples of upper and lower limits for the content of the photopolymerization initiator in the undercoating agent include 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, and 0% by mass. In one embodiment, the content is preferably 0 to 10% by mass.

<Polyisocyanate (D): Also referred to as component (D)>
In one embodiment, the undercoating agent may contain a polyisocyanate. The component (D) may be used alone or in combination of two or more kinds.

In this disclosure, a "polyisocyanate" is a compound that has two or more isocyanate groups (-N=C=O).

Examples of polyisocyanates include linear aliphatic polyisocyanates, branched aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic polyisocyanates, and their biurets, isocyanurates, allophanates, adducts, etc.

Examples of linear aliphatic polyisocyanates include methylene diisocyanate, dimethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, octamethylene diisocyanate, nonamethylene diisocyanate, and decamethylene diisocyanate.

Examples of branched aliphatic polyisocyanates include diethyl pentylene diisocyanate, trimethylbutylene diisocyanate, trimethylpentylene diisocyanate, trimethylhexamethylene diisocyanate, etc.

Examples of alicyclic polyisocyanates include monocyclic alicyclic polyisocyanates, crosslinked cyclic alicyclic polyisocyanates, and condensed cyclic alicyclic polyisocyanates.

Examples of monocyclic alicyclic polyisocyanates include hydrogenated xylene diisocyanate, isophorone diisocyanate, cyclopentylene diisocyanate, cyclohexylene diisocyanate, cycloheptylene diisocyanate, cyclodecylene diisocyanate, 3,5,5-trimethylcyclohexylene diisocyanate, and dicyclohexylmethane diisocyanate.

Examples of crosslinked alicyclic polyisocyanates include tricyclodecylene diisocyanate, adamantane diisocyanate, and norbornene diisocyanate.

Examples of condensed ring alicyclic polyisocyanates include bicyclodecylene diisocyanate.

Examples of aromatic groups include monocyclic aromatic groups and condensed ring aromatic groups. In addition, one or more hydrogen atoms of the aromatic group may be substituted with a linear or branched alkyl group.

Examples of monocyclic aromatic groups include phenyl, tolyl, and mesityl groups. Examples of condensed ring aromatic groups include naphthyl and naphthylene groups.

Examples of aromatic polyisocyanates include monocyclic aromatic polyisocyanates and condensed ring aromatic polyisocyanates.

Examples of monocyclic aromatic polyisocyanates include dialkyl diphenylmethane diisocyanates such as 4,4'-diphenyldimethylmethane diisocyanate, tetraalkyl diphenylmethane diisocyanates such as 4,4'-diphenyltetramethylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl isocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, m-tetramethylxylylene diisocyanate, etc.

Examples of condensed ring aromatic polyisocyanates include 1,5-naphthylene diisocyanate.

The biuret form of polyisocyanate is
The structural formula:
[In the formula, n ^b is an integer of 0 or more, R ^bA to R ^bE each independently represent an alkylene group or an arylene group, and R ^bα to R ^bβ each independently represent an isocyanate group or
(n ^b1 is an integer of 0 or more, R ^b1 to R ^b5 are each independently an alkylene group or an arylene group, and R ^b ' to R ^b '' are each independently an isocyanate group or a group of R ^bα to R ^bβ themselves. R ^b4 to R ^b5 and R ^b '' may be different groups for each structural unit. R ^bD to R ^bE and R ^bβ may be different groups for each structural unit.)

Examples of biuret polyisocyanates include Duranate 24A-100, Duranate 22A-75P, and Duranate 21S-75E (all manufactured by Asahi Kasei Corporation), and Desmodur N3200A (biuret of hexamethylene diisocyanate) (all manufactured by Sumika Covestro Urethane).

Isocyanurate of polyisocyanate is
The structural formula:
[In the formula, n ⁱ is an integer of 0 or more, R ^iA to R ^iE each independently represent an alkylene group or an arylene group, and R ^iα to R ^iβ each independently represent an isocyanate group or
(n ⁱ¹ is an integer of 0 or more, R ⁱ¹ to R ⁱ⁵ are each independently an alkylene group or an arylene group, and R ⁱ ' to R ⁱ " are each independently an isocyanate group or a group represented by R ^iα to R ^iβ themselves. R ⁱ⁵ and R ⁱ " may be different groups for each structural unit. R ^iD to R ^iE and R ^iβ may be different groups for each structural unit.)

Commercially available polyisocyanate isocyanurate products include Duranate TPA-100, Duranate TKA-100, Duranate MFA-75B, and Duranate MHG-80B (all manufactured by Asahi Kasei Corporation), Coronate HXR, Coronate HX, and Coronate HK (isocyanurate of hexamethylene diisocyanate) (all manufactured by Tosoh Corporation), Takenate D-127N (isocyanurate of hydrogenated xylene diisocyanate) (all manufactured by Mitsui Chemicals, Inc.), and VESTANAT Examples include T1890/100 (isocyanurate of isophorone diisocyanate (both manufactured by Evonik Corporation), Takenate D-204EA-1 (isocyanurate of tolylene diisocyanate) (both manufactured by Mitsui Chemicals, Inc.), and Coronate 2037 (both manufactured by Tosoh Corporation).

Allophanate forms of polyisocyanates are
The structural formula:
[In the formula, n is an integer of 0 or more, R ^A is an alkyl group or an aryl group, R ^B to R ^G are each independently an alkylene group or an arylene group, and R ^α to R ^γ are each independently an isocyanate group or
(n1 is an integer of 0 or more, R ¹ to R ⁶ are each independently an alkylene group or an arylene group, and R' to R''' are each independently an isocyanate group or a group represented by R ^α to R ^γ themselves. R ¹ to R ⁴ and R' to R'' may each represent a different group in each of the structural units. R ^B to R ^E and R ^α to R ^β may each represent a different group in each of the structural units.)

Commercially available allophanate polyisocyanate products include Coronate 2793 (manufactured by Tosoh Corporation) and Takenate D-178N (manufactured by Mitsui Chemicals, Inc.).

Polyisocyanate adducts are
The structural formula:
[In the formula, n ^ad is an integer of 0 or more, R ^adA to R ^adE each independently represent an alkylene group or an arylene group, and R ^ad1 to R ^ad2 each independently represent
(Wherein, n ^ad' is an integer of 0 or more,
R ^ad' to R ^ad'' each independently represent an alkylene group or an arylene group;
R ^ad''' is a group of R ^ad1 to R ^ad2 themselves,
R ^ad' to R ^ad''' may be different groups for each structural unit.
and R ^adD to R ^adE and R ^ad2 may be different groups for each structural unit.
An adduct of trimethylolpropane and polyisocyanate represented by the formula:
The following structural formula
[In the formula, n ^ad1 is an integer of 0 or more,
R ^adα to R ^adε each independently represent an alkylene group or an arylene group;
R ^adA to R ^adB are each independently
(In the formula, n ^{ad1 '} is an integer of 0 or more,
R ^adδ' to R ^adε' each independently represents an alkylene group or an arylene group;
R ^adB' is a group of R ^adA to R ^adB themselves;
R ^adδ' to R ^adε' and R ^adB' may be different groups for each structural unit.
R ^adδ to R ^adε may be different groups for each structural unit.]
Examples thereof include an adduct of glycerin and polyisocyanate represented by the following formula:

Examples of polyisocyanate adducts include Duranate P301-75E (both manufactured by Asahi Kasei Corporation), Takenate D110N, Takenate D160N (both manufactured by Mitsui Chemicals, Inc.), Coronate L, Coronate HL (both manufactured by Tosoh Corporation), etc.

Examples of upper and lower limits for the NCO content (NCO%) of the polyisocyanate include 30, 25, 20, 15, and 10%. In one embodiment, the NCO content (NCO%) is preferably 10 to 30%.

Examples of the upper and lower limits of the isocyanate group equivalent of the polyisocyanate include 420, 400, 350, 300, 250, 200, 150, and 140 g/eq. In one embodiment, the isocyanate group equivalent is preferably 140 to 420 g/eq.

In this disclosure, isocyanate group equivalent weight means the calculated mass per mole of isocyanate groups (g/eq).

The upper and lower limits of the ratio (NCO/OH) of the isocyanate group equivalent of the polyisocyanate to the sum of the hydroxyl group equivalents of the (A) and (B) components are, for example, 1, 0.9, 0.75, 0.5, 0.25, 0.1, 0.05, 0, etc. In one embodiment, the above ratio (NCO/OH) is preferably 0 to 1.

Examples of the upper and lower limits of the amount of OH groups consumed are 150, 125, 100, 75, 50, 25, and 10 mg KOH/g. In one embodiment, the amount of OH groups consumed is preferably 10 to 150 mg KOH/g.

In the present disclosure, the amount of consumed OH groups is an index showing how much of the OH groups in the components (A) and (B) are consumed by adding NCO. The amount of consumed OH groups is calculated by the following formula: Amount of consumed OH groups = Amount of added polyisocyanate / Isocyanate group equivalent × 56.1
It is calculated as follows.

Examples of upper and lower limits for the polyisocyanate content in the undercoating agent include 40, 30, 20, 15, 10, 5, and 0% by mass. In one embodiment, the content is preferably 0 to 40% by mass.

<Organic Solvent (E): Also referred to as component (E)>
In one embodiment, the undercoating agent may contain an organic solvent. The organic solvent may be used alone or in combination of two or more kinds.

Examples of organic solvents include ketone solvents such as methyl ethyl ketone, acetylacetone, methyl isobutyl ketone, and cyclohexanone; aromatic solvents such as toluene and xylene; alcohol solvents such as methanol, ethanol, n-propanol, isopropanol, and butanol; glycol ether solvents such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether, and propylene glycol monomethyl ether acetate; ester solvents such as ethyl acetate, butyl acetate, methyl cellosolve acetate, and cellosolve acetate; petroleum-based solvents such as Solvesso #100 and Solvesso #150 (all trade names, manufactured by Exxon Corporation); haloalkane solvents such as chloroform; and amide solvents such as dimethylformamide. Among these, ketone solvents are preferred from the viewpoint of the pot life of the undercoat agent of the present invention, and among ketone solvents, acetylacetone is preferred.

The upper and lower limits of the organic solvent content in the undercoating agent are 95, 90, 80, 70, 60, 55, 50, 45, 40, 35, 30, 25, 20, 15, 10, 5, and 0% by mass. In one embodiment, the content is preferably about 50 to 95% by mass. The organic solvent contained in the undercoating agent may include the organic solvent used in producing components (A) to (D).

<Curing catalyst (F): Also referred to as component (F)>
In one embodiment, the undercoat agent may contain a curing catalyst. The curing catalyst may be used alone or in combination of two or more kinds.

Examples of component (F) include inorganic catalysts and organic catalysts.

Examples of inorganic catalysts include typical metal catalysts and transition metal catalysts.

Typical metal catalysts include tin catalysts and bismuth catalysts.

Examples of tin catalysts include dibutyltin dilaurate and dioctyltin dilaurate.

Examples of bismuth catalysts include bismuth octoate.

Examples of transition metal catalysts include titanium catalysts, zirconium catalysts, iron catalysts, etc.

Examples of titanium catalysts include titanium ethyl acetoacetate.

Examples of zirconium catalysts include zirconium tetraacetylacetonate.

Examples of iron catalysts include iron acetylacetonate.

Examples of organic catalysts include amine catalysts.

Examples of amine catalysts include diazabicyclooctane, dimethylcyclohexylamine, tetramethylpropylenediamine, ethylmorpholine, dimethylethanolamine, triethylamine, and triethylenediamine.

Examples of upper and lower limits for the content of the curing catalyst in the undercoating agent include 1, 0.9, 0.75, 0.5, 0.25, 0.1, 0.09, 0.05, 0.02, 0.01, and 0% by mass. In one embodiment, the content of the curing catalyst in the undercoating agent is preferably about 0 to 1% by mass.

<Additives>
The undercoat agent may contain an agent other than the components (A) to (F) as an additive. Examples of additives include polymerization inhibitors, antioxidants, light stabilizers, defoamers, surface conditioners, pigments, antistatic agents, metal oxide fine particle dispersions, and organic fine particle dispersions. In one embodiment, the content of the additive is 0.1 to 10% by mass, less than 10% by mass, less than 5% by mass, less than 1% by mass, less than 0.1% by mass, less than 0.01% by mass, or 0% by mass of the undercoat agent. Examples of the additive content are 0.1 to 10% by mass, less than 10% by mass, less than 5% by mass, less than 1% by mass, less than 0.1% by mass, less than 0.01% by mass, or 0% by mass of any of the components (A) to (F).

The undercoating agent can be obtained by mixing components (A) to (B) and, if necessary, components (C) to (F) and/or additives by any of a variety of known means. The order in which the components are added is not particularly limited. As a dispersion/mixing means, any of a variety of known devices (emulsion disperser, ultrasonic dispersion device, etc.) can be used.

In one embodiment, the undercoat agent is used as an undercoat agent for active energy ray-curable resins, etc.

[Cured product]
The present disclosure provides a cured product of the undercoating agent.

In one embodiment, the cured product is a cured product obtained by irradiating the undercoating agent with active energy rays, or a cured product obtained by thermally curing the undercoating agent and then irradiating it with active energy rays. Examples of curing conditions include those described below.

[Laminate]
The present disclosure provides a laminate comprising an undercoat agent cured product layer comprising a cured product of the undercoat agent laminated on at least one surface of a substrate. In one embodiment, an active energy ray curable resin cured product layer is laminated on the undercoat agent cured product layer.

Various known substrates are used. Examples of substrates include polycarbonate substrates, acrylic substrates (polymethyl methacrylate substrates, etc.), polystyrene substrates, polyester substrates, polyolefin substrates, epoxy resin substrates, melamine resin substrates, triacetyl cellulose substrates, ABS substrates, AS substrates, norbornene-based resin substrates, cyclic olefin substrates, polyvinyl alcohol substrates, etc. Furthermore, a deposition layer of metal oxide or the like, an easy-adhesion layer, a hard coat layer, etc. may be provided on the surface. The thickness of the substrate is not particularly limited, but is preferably about 50 to 2000 μm. The thickness of the undercoat layer is not particularly limited, but is preferably about 0.1 to 5 μm.

The laminate is manufactured by various known methods. In one embodiment, the manufacturing method of the laminate includes a step of applying an undercoat agent to at least one side of a substrate (coating step), and a step of forming an undercoat agent cured product layer by thermal curing as necessary (thermal curing step). In one embodiment, the film has an active energy ray curable resin cured product layer laminated on the undercoat agent cured product layer. In this case, the manufacturing method further includes a step of applying an active energy ray curable resin to the undercoat agent cured product layer (coating step), a step of drying as necessary (drying step), and a step of forming an active energy ray curable resin cured product layer by irradiating with active energy rays (active energy ray curing step).

(Coating process)
Examples of the coating method include bar coater coating, wire bar coating, Mayer bar coating, air knife coating, gravure coating, reverse gravure coating, flow coat coating, offset printing, flexographic printing, and screen printing.

The coating amount is not particularly limited. The coating amount is preferably about 0.1 to 30 g/ ^m2 , and more preferably about 1 to 20 g/ ^m2 , in terms of mass after drying.

(Thermal curing process)
The drying method may be, for example, drying with a circulating air dryer, etc. The drying conditions may be, for example, leaving the material to stand at 80 to 120° C. for 30 seconds to 10 minutes, etc.

When producing a film, an aging treatment is carried out after drying if necessary. One example is aging treatment at 40°C for 72 hours.

(Active energy ray curing process)
Examples of active energy rays used in the active energy ray curing reaction include ultraviolet rays and electron beams. Examples of light sources for ultraviolet rays include ultraviolet ray irradiation devices having xenon lamps, high pressure mercury lamps, and metal halide lamps. The light quantity, light source arrangement, transport speed, and the like can be adjusted as necessary. When using a high pressure mercury lamp, it is preferable to perform curing at a transport speed of about 2 to 50 m/min for one lamp having a light quantity of about 80 to 160 W/cm. On the other hand, in the case of electron beams, it is preferable to perform curing under conditions of a transport speed of about 5 to 50 m/min using an electron beam accelerator having an acceleration voltage of about 10 to 300 kV.

Examples of active energy ray curable resins include resins that are cured by radicals such as (meth)acrylic esters, urethane (meth)acrylates, polyester (meth)acrylates, epoxy (meth)acrylates, and polyacrylic (meth)acrylates (for example, the "Beamset Series" manufactured by Arakawa Chemical Industries, Ltd.), resins that cure epoxides, oxetanes, vinyl ethers, etc. with cations or anions, and resins that cure by the ene-thiol reaction of alkenes and thiols. These may be used in combination.

The present invention will be specifically described below through examples and comparative examples. However, the above description of the preferred embodiment and the following examples are provided for illustrative purposes only and are not provided for the purpose of limiting the present invention. Therefore, the scope of the present invention is not limited to the embodiments or examples specifically described in this specification, but is limited only by the claims. In each example and comparative example, unless otherwise specified, numerical values such as parts and percentages are based on mass.

<Component (A)>
Production Example 1-1: Production of hydroxyl group-containing (meth)acrylic polymer A reaction vessel equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel and a nitrogen inlet tube was charged with 275.6 parts of methyl methacrylate (79.9% by mass in the monomer components), 10.3 parts of n-butyl acrylate (3% by mass in the monomer components), 58.6 parts of 2-hydroxyethyl acrylate (17% by mass in the monomer components), and 0.4 parts of styrene (0.1% by mass in the monomer components), as well as 125 parts of methyl ethyl ketone and 525 parts of ethyl acetate, and the reaction system was set to 80 ° C. Next, 2.1 parts of 2,2'-azobis (2, methylvaleronitrile) were charged and kept at about 80 ° C. for 5 hours. Next, 5.2 parts of 2,2'-azobis (2,4-dimethylbutyronitrile) were charged, and the reaction system was kept at about the same temperature for another 4 hours. Thereafter, the reaction system was cooled to room temperature to obtain a solution of hydroxyl group-containing (meth)acrylic polymer 1 (non-volatile content: 35%).

Hydroxyl-containing (meth)acrylic polymers other than those in Production Example 1-1 were produced in the same manner as in Production Example 1-1, except that the amounts of monomers used were changed as shown in the table below.

MMA: methyl methacrylate BA: n-butyl acrylate HEA: 2-hydroxyethyl acrylate St: styrene EA: ethyl acrylate

<Component (B)>
Production Example 2-1
A four-neck flask equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet was charged with 125 parts of butyl acetate, 50 parts of glycidyl methacrylate (hereinafter, GMA), 50 parts of MMA, and 1 part of azobisisobutyronitrile (hereinafter, AIBN), and stirred. The mixture was heated to 100 ° C. with nitrogen gas flow, and then reacted for 10 hours. After the reaction was completed, the mixture was cooled to 60 ° C., and 25 parts of acrylic acid, 0.1 parts of triphenylphosphine, and 0.05 parts of methoquinone were charged. The nitrogen inlet was replaced with an air bubbling device, and the mixture was stirred while bubbling air into the reaction solution. The mixture was heated to 110 ° C. and reacted for 9 hours while keeping the temperature constant, to obtain resin 1 with a resin solid content of 50%. The weight average molecular weight (polystyrene equivalent value by GPC) was 9,000. The weight average molecular weight is a value measured by gel permeation chromatography (manufactured by Tosoh Corporation, product name "HLC-8220"; column: manufactured by Tosoh Corporation, product name "TSKgel Super HM-L"; three columns connected in series. 48.6 parts of butyl acetate, 32.6 parts of glycidyl methacrylate (hereinafter, GMA), 32.6 parts of azobisisobutyroyl methacrylate (hereinafter, GMA), 2.2 parts of azobisisobutyroyl methacrylate (hereinafter, GMA), 1.0 ...

1.6 parts of nitrile (hereinafter, AIBN) was charged and stirred, and the temperature was raised to 100 ° C. under nitrogen gas flow, and then the reaction was allowed to proceed for 10 hours. After the reaction was completed, the mixture was cooled to 60 ° C., and 16.6 parts of acrylic acid, 0.1 parts of triphenylphosphine, and 0.5 parts of methoquinone were charged, and the nitrogen inlet was replaced with an air bubbling device, and the mixture was stirred while bubbling air into the reaction solution, and the mixture was heated to 110 ° C. and allowed to react for 9 hours while keeping the temperature constant, thereby obtaining a resin 1 having a resin solid content of 50% (Table 1). The weight average molecular weight (polystyrene equivalent value by GPC) was 12,000, and the molecular weight per acrylic group was calculated to be 214. The weight average molecular weight indicates the value measured by gel permeation chromatography (manufactured by Tosoh Corporation, product name "HLC-8220", column: manufactured by Tosoh Corporation, product name "TSKgel superHZ2000" three columns connected in series.

Hydroxyl-containing poly(meth)acrylates other than those in Production Example 2-1 were produced in the same manner as in Production Example 2-1, except that the amounts of monomers used were changed as shown in the table below. In the table, the values for GMA and MMA indicate the contents in the polymer before the addition of acrylic acid (AA), and the value for acrylic acid indicates the value relative to 100% by mass of GMA.

GMA: glycidyl methacrylate MMA: methyl methacrylate AA: acrylic acid The unit of acrylic equivalent is g/eq.

Example 1
An undercoat agent was produced by charging 70 parts of hydroxyl-containing (meth)acrylic polymer 1 of Production Example 1-1 as component (A), 30 parts of hydroxyl-containing poly(meth)acrylate A of Production Example 2-1 as component (B), and 5 parts of Omnirad 184 (manufactured by IGM) as component (C) and stirring for 15 minutes.

Undercoating agents other than those in Example 1 were produced in the same manner as in Example 1, except that the component compositions were changed as shown in the table below.

Coronate HX: manufactured by Tosoh Corporation, hexamethylene diisocyanate nurate, solid content concentration 100% by mass, NCO%=20.5 to 22.0%

(Manufacture of Laminates)
(1) Formation of Undercoat Agent Cured Product Layer The undercoat agents according to Examples 1 to 13 and Comparative Examples 1 to 5 were applied to a PC/PMMA two-layer sheet (Technoloy C001: manufactured by Sumitomo Chemical Co., Ltd.) so that the film thickness after drying would be 2 μm, and for Examples 1 to 12 and Comparative Examples 1 to 5, after drying at 100°C for 60 seconds, UV curing was carried out at 300 mJ/cm ^2. For Examples 13 and 14, after drying at 100°C for 5 minutes, UV curing was carried out.
(2) Formation of active energy ray curable resin cured product layer An active energy ray curable resin was applied onto the undercoat agent cured product layer so that the film thickness after drying would be 5 to 6 μm, and after drying at 80°C for 60 seconds, UV curing was performed at 300 mJ/ ^cm2 . As the active energy ray curable resin, evaluation was performed using Beamset 700 (manufactured by Arakawa Chemical Industries, Ltd.) of a multifunctional acrylic ester system (dipentaerythritol polyacrylate). As a photopolymerization initiator, Omnirad 184 was added at 5% relative to the solid content of the active energy ray curable resin.

(Drying property)
The state of the cured undercoating agent layer was evaluated according to the following criteria.
○: Not sticky ×: Sticky

(Adhesion to substrate)
After the undercoat agent cured product layer was formed, the adhesion was evaluated by a cellophane tape cross-cut peel test specified in JIS K 5400. The evaluation criteria are as follows.
○…100/100 in the 100-grid grid test
△…50-70/100 in the 100-grid test
×…20 or less in the 100-grid test/100

(exterior)
The appearance of the laminate (the undercoat agent cured product layer and the active energy ray curable resin cured product layer) was evaluated according to the following criteria.
○: Colorless and transparent ×: Whitened

(Adhesion to active energy ray-curable resin layer)
After the active energy ray-curable resin cured product layer was formed, the adhesion was evaluated using the same method and evaluation criteria as for the adhesion to the substrate.

Evaluation Examples Undercoating agents for evaluation examples were produced in the same manner as in Example 1, except that the component compositions were changed as shown in the table below.

(Heating elongation)
A cured undercoating agent was prepared on a PET film (Cosmoshine A4100, manufactured by Toyobo Co., Ltd.) in the same manner as described above, and a film cut to a size of 1.5 cm x 13 cm was placed in a 150°C forward air dryer and stretched using a Tensilon universal material testing machine (manufactured by A&D Co., Ltd.) until cracks appeared in the coating film, and the heat elongation was calculated using the following formula.
Heat elongation (%) =
[(Film length after stretching) - (Film length before stretching)]/(Film length before stretching) x 100

Claims (5)

The composition comprises a hydroxyl group-containing (meth)acrylic polymer (A) having no (meth)acryloyl group and a hydroxyl group-containing polymer poly(meth)acrylate (B),
The total content of the aromatic polymerizable unsaturated monomer and the alicyclic polymerizable unsaturated monomer in the component (A) is less than 10% by mass,
The (meth)acrylic equivalent of the component (B) is 300 to 375 g/eq.
An undercoating agent that does not contain a polyisocyanate (D) . The undercoating agent according to claim 1, wherein the total content of the aromatic polymerizable unsaturated monomer and the alicyclic polymerizable unsaturated monomer in component (A) is 0.1% by mass or more. A cured product of the undercoat agent according to claim 1 or 2. A laminate in which a layer of a cured undercoat agent containing the cured undercoat agent according to claim 3 is laminated on at least one surface of a substrate. The laminate according to claim 4, in which an active energy ray-curable resin cured product layer is laminated on the undercoat agent cured product layer.