JP7429092B2 - Acrylic resin composition and laminate - Google Patents

Description

The present invention relates to an acrylic resin composition and a laminate that can be used for civil engineering and construction purposes.

Conventionally, unsaturated polyester resins, epoxy resins, polyurethane resins, and the like have been used as coating agents for forming coating films on base materials such as floors, walls, and paved roads.
Although unsaturated polyester resins have excellent solvent resistance, they have poor weather resistance, large shrinkage upon curing, and poor low-temperature workability.
Although epoxy resins have excellent alkali resistance and excellent adhesion to substrates, they have poor weather resistance, long curing times, and poor curing properties at low temperatures.
Although polyurethane resin has excellent elasticity and flexibility, it has poor chemical resistance and weather resistance.
Furthermore, as coating materials, vinyl ester resins and acrylic resins are often used, which have excellent low-temperature curability, weather resistance, and chemical resistance.
Vinyl ester resins and acrylic resins have a unique odor caused by low molecular weight monomers such as styrene and methyl methacrylate, so the odor during work is a problem.

These materials have been used in a variety of ways as coating agents to form coatings on base materials such as floors, walls, and paved roads. have also been proposed.
In recent years, interest in environmental issues has increased, and the use of resin compositions containing low molecular weight monomers such as styrene and methyl methacrylate is highly volatile and contains components with strong odors. There is a tendency to be restrained.
To address these problems, a resin composition using an air-drying radically polymerizable unsaturated group-containing resin (1) and phenoxyethyl (meth)acrylate has been proposed (for example, Patent Document 1). According to the invention of Patent Document 1, it is reported that it has low odor and excellent water resistance, and that it cures quickly in air without being inhibited by oxygen from curing the coating film, even without using paraffin wax. ing.
(meth)acrylate oligomers having at least two (meth)acryloyl groups at the molecular terminals, (meth)acrylate monomers having acetoacetoxyl groups, (meth)acrylate monomers having long-chain alkyl groups having 8 or more carbon atoms A resin composition using wax as an essential component has been proposed (for example, Patent Document 2). According to the invention of Patent Document 2, since a highly volatile monomer is not used, it is effective in low odor and low toxicity, can be radically cured, has excellent drying properties on the surface of the coating, and can be cured by further curing. It has been reported that it has excellent strength properties, chemical resistance, heat resistance, weather resistance, and secondary adhesion, and is very useful for civil engineering and construction materials such as waterproof coatings.
A resin composition composed of a resin part made of a radically polymerizable methacrylic resin, a methacrylate monomer, and a curing accelerator, an aggregate part, and a curing agent part made of methyl ethyl ketone peroxide, wherein the cured product of the resin part is A material having a shrinkage rate of 1.0% or more and 3.0% or less and a shrinkage stress of 2 N/mm ² or more and 8 N/mm ^{2 or} less has been proposed (for example, Patent Document 3). According to the invention disclosed in Patent Document 3, the stress caused by thermal expansion is alleviated due to the rapid hardening by radical curing and the effect of very slight contraction, which reduces blistering caused by expansion of the coating film and It has been reported that peeling from the substrate does not occur.
(A) (meth)acrylic polymer, (B) (meth)acrylate having at least one aromatic ring selected from the group consisting of benzyl (meth)acrylate, phenyl (meth)acrylate, and phenoxyethyl (meth)acrylate. , (C) hydroxyalkyl (meth)acrylate, and (D) a thermal polymerization initiator. A thermosetting resin composition has been proposed (for example, Patent Document 4). According to the invention of Patent Document 4, it is reported that a thermosetting resin composition having a cured product with high transparency can be obtained.
It has been proposed to use a specific low acid value unsaturated polyester, a polymerizable monofunctional (meth)acrylic monomer, and a thickener for thermoplastic resin powder in a specific composition ratio (for example, Patent Document 5) . According to the invention of Patent Document 5, there is no styrene volatilization, thickening is possible in a short time, workability is good, and furthermore, curability and surface drying properties are good, and cast plates and laminates can be used. It has been reported that both the physical properties and the reactivity of photopolymerization and thermal polymerization are superior to existing cured styrene-type vinyl ester resins.

Japanese Patent Application Publication No. 2004-143393 Japanese Patent Application Publication No. 2005-120305 Japanese Patent Application Publication No. 2010-084048 Japanese Patent Application Publication No. 2012-126896 Japanese Patent Application Publication No. 2007-291179

Air-drying radically polymerizable unsaturated group-containing resins and (meth)acrylates having at least two or more (meth)acryloyl groups at the molecular terminals as described in Patent Documents 1 to 3 and Patent Documents 5 Resin compositions made by blending oligomers and radically polymerizable methacrylic resins with (meth)acrylic monomers have excellent surface drying properties of coating films, but according to studies conducted by the present inventors, the cured coating film of the resin composition is When obtained, the coating film becomes cloudy and has low transparency, making it difficult to apply it to a coating method that takes advantage of the texture of stone or aggregate.
Further, a thermosetting resin composition containing an acrylic polymer, a (meth)acrylate having an aromatic ring, a hydroxyalkyl (meth)acrylate, and a thermal polymerization initiator, as described in Patent Document 4, is Although the resulting cured product has very good transparency, it cannot be cured in an atmosphere below room temperature. If the curing catalyst is changed and cured in an atmosphere below room temperature, the coating film will be extremely hard and brittle, resulting in cracking or chipping when coated on stone or aggregate. Therefore, it was difficult to apply.
The present invention was made in view of the above circumstances, and it is possible to obtain a cured coating film that is low in odor, has excellent curability, and has little turbidity, and has a design that takes advantage of the texture of stone and aggregate. An object of the present invention is to provide an acrylic resin composition and a laminate that can be applied to certain coating methods.

As a result of intensive studies, the present inventors found that by creating a resin composition containing a resin containing a specific type of monomer and a specific amount of wax, it has low odor, excellent curability, and no turbidity. The inventors have discovered an acrylic resin composition and a laminate that can be applied to a decorative coating method that takes advantage of the texture of stones and aggregates because they can obtain a less cured coating film, and have completed the present invention. Ta.

The present invention for solving the above problems has the following aspects.
The acrylic resin composition of the present invention comprises a monomer (A) having one (meth)acryloyl group in the molecule, and a monomer (B) having two or more (meth)acryloyl groups in the molecule. ), a polymer (C) having 60% by mass or more of methyl methacrylate units, and a wax (D), and (meth)acrylate (a1) having an aromatic ring as the monomer (A), It contains hydroxyalkyl (meth)acrylate (a2) and (meth)acrylate (a3) whose homopolymer Tg is -10°C or less.

According to the present invention, it is possible to obtain a cured coating film that is low in odor, has excellent curability, and has little turbidity, so it can be applied to a coating method that has a design that takes advantage of the texture of stone or aggregate. It is possible to provide an acrylic resin composition and a laminate that can be used.

The present invention will be explained in detail below.
Note that in this specification, "(meth)acrylic" is a general term for acrylic and methacryl. "(Meth)acrylate" is a general term for acrylate and methacrylate. "(Meth)acryloyl group" is a general term for acryloyl group and methacryloyl group, and has the general formula CH ₂ =C(R)-C(=O)-[R represents a hydrogen atom or a methyl group. ]. "Acrylic" is a general term for acrylic and methacrylic.

"Acrylic resin composition"
The acrylic resin composition of the present invention (hereinafter abbreviated as "resin composition") is a resin composition that can be used for civil engineering, construction, etc., and has one (meth)acryloyl group in the molecule. a monomer (A) having two or more (meth)acryloyl groups in the molecule, a polymer (C) having 60% by mass or more of methyl methacrylate units, and a wax (D). ). Further, the resin composition of the present invention includes, as the monomer (A), at least one aromatic ring selected from the group consisting of benzyl (meth)acrylate, phenyl (meth)acrylate, and phenoxyethyl (meth)acrylate. A (meth)acrylate (a1) having a hydroxyalkyl (meth)acrylate (a2), a (meth)acrylate (a3) having a homopolymer glass transition temperature (hereinafter also referred to as Tg) of -10°C or less, Contains.

<Monomer (A)>
Monomer (A) is a monomer having one (meth)acryloyl group. The monomer (A) is a component that can adjust the viscosity of the resin composition and the mechanical strength of the cured coating formed from the resin composition.
Examples of the monomer (A) include the following (a1) to (a4). Among these, each of (a1), (a2), and (a3) is preferred in that the viscosity of the resin composition can be easily adjusted and the mechanical strength of the adhesive protective layer formed from the resin composition can be easily adjusted. It is preferable to blend at least one kind.
(a1): (meth)acrylate monomer having an aromatic ring.
(a2): hydroxyalkyl (meth)acrylate.
(a3): A (meth)acrylate whose homopolymer Tg is -10°C or less (excluding the above (a1) and (a2)).
(a4): Monomer (A) other than monomers (a1) to (a3) (excluding the above (a1), (a2) and (a3)).

Specific examples of monomer (a1) include benzyl (meth)acrylate, phenyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, nonylphenoxypolyethylene glycol (meth)acrylate, and phenoxypolypropylene. Glycol (meth)acrylate, 2-(meth)acryloyloxyethyl-2-hydroxypropyl phthalate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 2-(meth)acryloyloxyethyl hydrogen phthalate, 2-(meth) Acryloyloxypropyl hydrogen phthalate, ethoxylated ortho-phenylphenol (meth)acrylate, phenol ethylene oxide (EO) modified acrylate, nonylphenol EO modified acrylate, 2-(meth)acryloyloxyethyl phthalate, 2-(meth) hexahydrophthalate Examples include (meth)acrylate monomers having an aromatic ring such as acryloyloxyethyl. Among these, from the viewpoint of transparency of the cured product, benzyl (meth)acrylate, phenyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenol EO-modified acrylate, and nonylphenol EO-modified acrylate are more preferred, and phenoxyethyl (meth)acrylate is more preferred. Acrylates are particularly preferred.
The content of monomer (a1) is preferably 40 to 70 parts by weight out of the total of 100 parts by weight of (A), (B) and (C).

Specific examples of monomer (a2) include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, hydroxyhexyl (meth)acrylate, and hydroxyoctyl (meth)acrylate. ) acrylate, hydroxyalkyl (meth)acrylate such as glycerin (meth)acrylate, and the like.
Among these, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, and 4-hydroxybutyl (meth)acrylate are preferred, and 2-hydroxypropyl methacrylate and 4-hydroxybutyl (meth)acrylate are particularly preferred.
The content of monomer (a2) is preferably 5 to 25 parts by weight out of the total of 100 parts by weight of (A), (B) and (C).

Specific examples of monomer (a3) include ethylene glycol monomethyl ether methacrylate, ethylene glycol monoethyl ether methacrylate, diethylene glycol monomethyl ether (meth)acrylate, diethylene glycol monoethyl ether (meth)acrylate, 2-ethoxylated 2 - Ethylhexyl (meth)acrylate, polyethylene glycol monomethyl ether (meth)acrylate, polyethylene glycol monoethyl ether (meth)acrylate, 2-ethylhexyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate Acrylate, undecyl (meth) acrylate, dodecyl (meth) acrylate, tridecyl (meth) acrylate, tetradecyl (meth) acrylate, pentadecyl (meth) acrylate, polyethylene glycol mono (meth) acrylate (the number of repeating ethylene glycol is 4 or more), Homopolymers such as polypropylene glycol mono(meth)acrylate (polypropylene glycol repeating number is 2 or more), 2-acryloyloxyethylsuccinic acid, etc. have a Tg of -10°C or less and have one (meth)acryloyl group. Examples include monomers having
Among these, 2-ethylhexyl (meth)acrylate, 2-ethoxylated 2-ethylhexyl (meth)acrylate, diethylene glycol monomethyl ether (meth)acrylate, and diethylene glycol monoethyl ether (meth)acrylate are preferred.
The content of monomer (a3) is preferably 5 to 25 parts by weight out of the total of 100 parts by weight of (A), (B) and (C).

The resin composition of the present invention may contain a monomer (a4) other than the monomers (a1) to (a3) to the extent that low odor, curability, etc. are not impaired.
As the monomer (a4), glycidyl group-containing methacrylates such as glycidyl methacrylate; carboxylic acid-containing (meth)acrylates such as 2-(meth)acryloyloxyethyl maleate; 3-methacryloxypropylmethyldimethoxysilane, 3-methacrylate A silane coupling agent having one (meth)acryloyl group such as roxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane; Fluorine atom-containing (meth)acrylates such as trifluoroethyl (meth)acrylate, tetrafluoroethyl (meth)acrylate, hexafluoroethyl (meth)acrylate, and octafluoroethyl acrylate; dimethylcyclohexyl (meth)acrylate, trimethylcyclohexyl (meth)acrylate Di- or trialkylcyclohexyl group-containing (meth)acrylates such as acrylate; examples include isobornyl methacrylate, dicyclopentenyloxyethyl (meth)acrylate, and the like.
Further, as the monomer (a4), a (meth)acrylate having a hetero ring selected from the group consisting of a furan ring, a hydrofuran ring, a pyran ring, and a hydropyran ring may be used.
Examples of the (meth)acrylate having a furan ring include furyl (meth)acrylate, furfuryl (meth)acrylate, and the like.
Examples of the (meth)acrylate having a hydrofuran ring include tetrahydrofuryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate, and the like.
Examples of the (meth)acrylate having a pyran ring include pyranyl (meth)acrylate.
Examples of the (meth)acrylate having a hydropyran ring include dihydropyranyl (meth)acrylate, tetrahydropyranyl (meth)acrylate, dimethyldihydropyranyl (meth)acrylate, dimethyltetrahydropyranyl (meth)acrylate, and the like.
The content of monomer (a4) is preferably 0 to 20 parts by weight out of the total of 100 parts by weight of (A), (B) and (C).

The monomer (A) is preferably 65 to 85 parts by weight, more preferably 70 to 85 parts by weight out of the total of 100 parts by weight of (A), (B) and (C). By controlling the monomer (A) to 65 parts by mass or more, the viscosity of the resin composition does not become too high and the workability becomes good. By controlling the monomer (A) to 85 parts by mass or less, the viscosity of the resin composition does not become too low and it is possible to coat the resin composition with an appropriate coating thickness during work.

<Monomer (B)>
Monomer (B) is a monomer having two or more (meth)acryloyl groups. Monomer (B) can impart toughness to the cured coating film and can improve the mechanical strength of the cured product.

As the monomer (B), ethylene glycol di(meth)acrylate, 1,3-propylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, ) acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate meth)acrylate, polybutylene glycol di(meth)acrylate, bisphenol A ethylene oxide adduct di(meth)acrylate, bisphenol A propylene oxide adduct di(meth)acrylate, bisphenol A diglycidyl ether (meth)acrylic acid adduct, Neopentyl glycol di(meth)acrylate, 1,4-cyclohexanedimethanol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, Examples include tris(2-(meth)acryloyloxyethyl)isocyanurate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like. Among these, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polybutylene glycol di(meth)acrylate, bisphenol A ethylene oxide adduct di(meth)acrylate, bisphenol A propylene oxide adduct di(meth)acrylate, ) Acrylates are preferred.
Monomer (B) may be used alone or in combination of two or more.

The content of monomer (B) is preferably 2 to 20 parts by mass, more preferably 2 to 15 parts by mass, when the total of components (A), (B), and (C) is 100 parts by mass. preferable. If the content of monomer (B) is 2 parts by mass or more, toughness can be imparted to the coating film and the mechanical strength of the coating film can be improved. If the content is 20 parts by mass or less, it will be possible to improve the mechanical strength of the coating film until it is cured. The time is not too short, the coating workability is good, and the toughness of the cured product is not impaired.

<Polymer (C)>
The polymer (C) has a methyl methacrylate unit content of 60% by mass or more, preferably 80% by mass or more, and is a component that can improve the viscosity and curability of the resin composition. It is preferable that polymer (C) is soluble in component (A) and component (B).
If the methyl methacrylate unit content of the polymer (C) is less than 60% by mass, the strength of the coating film may be impaired.

Further, the polymer (C) preferably has a glass transition temperature (Tg _C ) of 60°C or higher, more preferably 60 to 110°C, and even more preferably 80 to 105°C. If the Tg _C of the polymer (C) is 60° C. or higher, the surface curability of the resin composition will be good. On the other hand, if the Tg _C of the polymer (C) is 110°C or less, the coating film can be prevented from becoming hard and brittle. In addition, when producing a resin composition, the solubility in monomer (A) and monomer (B) is improved.

The glass transition temperature (Tg _C ) of the polymer (C) is determined by the following formula (1) based on the Fox formula.
1/(273+Tg _C )=Σ(W _n /(273+Tg _n ))...(1)

In formula (1), “Tg _C ” is the glass transition temperature (° C.) of the polymer (C). The polymer (C) is a polymer of n types (n≧1) of monomers (1), (2)...(n), and "W _n " is a polymer of each monomer (1), (2)...(n) that constitutes the polymer (C). It is the mass fraction of monomer units, and " _Tgn " is the glass transition temperature (° C.) of a homopolymer of each monomer unit constituting the polymer (C).

Here, if the polymer (C) is, for example, a copolymer consisting of two or more types of monomers (1), (2)..., the glass transition temperature (Tg _C ) of the polymer (C) is Fox It is obtained from the formula shown in the following formula (1') based on the formula.
1/(273+Tg _C )=W ₁ /(273+Tg ₁ )+W ₂ /(273+Tg ₂ )+...(1')

In formula (1'), "W ₁ ", "W ₂ "... are the mass fractions of the monomer units (1), (2)..., respectively, and "Tg ₁ ", "Tg ₂ ''... is the glass transition temperature (°C) of the homopolymer of monomer units (1), (2)..., respectively. For these glass transition temperatures, the values described in "Polymer Handbook 3rd Edition" (A WILEY-INTERSCIENCE PUBLICATION, 1989) can be used.

The type of polymer (C) is not particularly limited as long as it contains 60% by mass or more of methyl methacrylate units, and examples thereof include (c-1) and (c-2) below.
(c-1): A homopolymer of methyl methacrylate, or a copolymer of methyl methacrylate and other alkyl (meth)acrylates (however, the methyl methacrylate unit is 60% by mass or more).
(c-2): A copolymer having a methyl methacrylate unit and a unit having a double bond (however, the methyl methacrylate unit is 60% by mass or more).
The polymer (C) may contain only one of (c-1) and (c-2), or may contain both.

[Polymer (c-1)]
The polymer (c-1) is a homopolymer of methyl methacrylate or a copolymer of methyl methacrylate and other alkyl (meth)acrylate (provided that the methyl methacrylate unit is 60% by mass or more). Other alkyl (meth)acrylates include methyl acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, amyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, ) acrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, dicyclopentenyl (meth)acrylate, 2-di Cyclopentenoxyethyl (meth)acrylate, isobornyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl ( Examples include meth)acrylate, 2-hydroxypropyl(meth)acrylate, 4-hydroxybutyl(meth)acrylate, and (meth)acrylic acid.
The polymer (c-1) may be used alone or in combination of two or more.

The mass average molecular weight (hereinafter referred to as "Mw") of the polymer (c-1) is preferably 10,000 to 200,000, more preferably 20,000 to 170,000, 30,000 to 100, 000 is particularly preferred. By setting Mw to the lower limit value or more, the strength of the cured coating film of the resin composition can be improved. If the Mw is below the upper limit, the solubility in the components (A) and (B) will be good when producing a resin composition.
The Mw of the polymer (c-1) is the molecular weight measured by gel permeation chromatography (GPC) after dissolving the resin in a solvent (tetrahydrofuran) in terms of polystyrene.

The content of the polymer (c-1) is preferably 1 to 20 parts by mass, and 5 to 15 parts by mass when the total of components (A), (B), and (C) is 100 parts by mass. part is more preferable. When the content of the polymer (c-1) is below the above-mentioned upper limit, the pot life of the resin composition (the time during which the composition has fluidity and can be used for coating) can be sufficiently ensured, and the coating operation can be completed easily. Improves sex. On the other hand, when the content of the polymer (c-1) is at least the above lower limit, the viscosity of the resin composition can be balanced, the curability thereof can be improved, and the curing time can be appropriately shortened.

In addition, the content of the polymer (c-1) is within the above range (5 to 20 parts by mass, when the total of components (A), (B), and (C) is 100 parts by mass. ) and is more preferably within a range that satisfies the following formula (2). If the following formula (2) is satisfied, the viscosity of the resin composition will not become too high and coating workability can be maintained favorably.

300,000<Mw of polymer (c-1) x content of polymer (c-1)<1,400,000 (2)
In formula (2), "content of polymer (c-1)" refers to the content of polymer (c-1) when the total of components (A), (B), and (C) is 100 parts by mass. 1) is the content (parts by mass).

When the polymer (c-1) is a mixture of polymers (c-1-1), (c-1-2)..., the following formula (2') is used instead of the above formula (2). Use.

300,000<{Mw of polymer (c-1-1) x content of polymer (c-1-1)} + {Mw of polymer (c-1-2) x polymer (c-1) -2) Content}+...<1,400,000...(2')

[Polymer (c-2)]
The polymer (c-2) is a copolymer having methyl methacrylate units and units having a double bond (provided that the methyl methacrylate units account for 60% by mass or more).
The double bond in the polymer (c-2) is a double bond that participates in a radical polymerization reaction, and functional groups having such a double bond include a vinyl group, an allyl group, a (meth)acryloyl group, etc. Can be mentioned. The polymer (c-2) can contribute to the mechanical strength of the cured coating film of the resin composition.

The polymer (c-2) may have acrylic monomer (cm2) units other than methyl methacrylate (cm1) units and units having double bonds. Other acrylic monomers (cm2) include monofunctional acrylic monomers, polyfunctional acrylic monomers, (meth)acrylic acid, and the like.

Specific monomers (cm2) include ethyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, t-butyl (meth)acrylate, sec-butyl (meth)acrylate, Alkyl (meth)acrylates such as 2-ethylhexyl (meth)acrylate; cycloalkyl (meth)acrylates such as isobornyl (meth)acrylate and cyclohexyl (meth)acrylate; alkyl (meth)acrylates having the above alkyl group having 2 or more carbon atoms; Examples of the acrylic unit that is not included in either the acrylate unit or the cycloalkyl (meth)acrylate unit include glycidyl (meth)acrylate and (meth)acrylic acid. These may be used alone or in combination of two or more.
Among the above monomers, alkyl methacrylates having alkyl groups having 2 to 4 carbon atoms, isobornyl (meth)acrylate, glycidyl (meth)acrylate, and (meth)acrylic acid are preferred.
The alkyl methacrylate having an alkyl group having 2 to 4 carbon atoms is preferably n-butyl methacrylate, i-butyl methacrylate, t-butyl methacrylate, or sec-butyl methacrylate, and more preferably n-butyl methacrylate.

The method for producing polymer (c-2) is not particularly limited, but the following production method is preferred.
That is, first, as a first step reaction, methyl methacrylate (cm1), a first reactive monomer having a first functional group capable of forming an ester, and other acrylic monomers as necessary. (cm2) to obtain a first copolymer having the first functional group.
Next, as a second step reaction, a second reactive monomer having a double bond and a second functional group capable of reacting with the first functional group to form an ester is added to the first copolymer. The first functional group and the second functional group are reacted to obtain a polymer (c-2) having methyl methacrylate units and a unit having a double bond.
Preferred combinations of the first functional group and the second functional group include a carboxy group and a glycidyl group, a hydroxy group and an isocyanate group, and the like.

More specific methods for producing the polymer (c-2) include the following methods.
In the first step reaction, methyl methacrylate (cm1), (meth)acrylic acid, and other acrylic monomers (cm2) as needed are suspended polymerized to form a first copolymer having a carboxy group. Get union.
Next, in the second stage reaction, the obtained first copolymer is added to methyl methacrylate (cm1) to form a solution, and glycidyl (meth)acrylate is added to the solution. Polymer (c-2) is obtained by reacting the carboxy group of the first copolymer with the glycidyl group of glycidyl (meth)acrylate to form an ester.

In the first stage reaction, the polymerization temperature during suspension polymerization is preferably in the range of 70 to 98°C, and the polymerization time is preferably about 2 to 5 hours.
The reaction temperature in the second stage reaction is preferably 90 to 95°C, and the reaction time is preferably about 1 to 4 hours.

The preferred composition ratio of the monomers used in the first stage reaction is 20 to 95% by mass of methyl methacrylate (cm1), 80 to 5% by mass of other acrylic monomers (cm2), and (meth)acrylic acid. is preferably 0.3 to 4% by mass. Furthermore, the content of (meth)acrylic acid is more preferably 0.3 to 2% by mass.
In the second stage reaction, it is preferable that the amount of methyl methacrylate monomer (cm1) is 70 to 150 parts by mass based on 100 parts by mass of the first copolymer. Furthermore, it is preferable to react 0.9 to 1.2 mol of glycidyl (meth)acrylate with respect to 1 mol of (meth)acrylic acid used in the first step reaction, and preferably 1.0 to 1.1 mol. It is more preferable to react.

The suspension used for suspension polymerization in the first stage reaction is preferably an aqueous suspension. Preferably, a dispersant is added to the aqueous suspension.
Dispersants are not particularly limited, and include, for example, poorly water-soluble inorganic compounds such as calcium phosphate, aluminum hydroxide, starch powder silica; nonionic polymer compounds such as polyvinyl alcohol, polyethylene oxide, and cellulose derivatives; poly(meth)acrylic acid. Examples include anionic polymer compounds such as alkali metal salts and alkali metal salts of copolymers of (meth)acrylic acid and methyl (meth)acrylate.
The amount of the dispersant added is preferably in the range of 0.005 to 5% by mass, more preferably in the range of 0.01 to 1% by mass, based on the suspension.

The suspension during the suspension polymerization preferably contains an electrolyte such as sodium carbonate, sodium sulfate, manganese sulfate, or the like. By containing an electrolyte, dispersion stability can be improved. The amount of electrolyte added may be set appropriately and is not particularly limited.

It is preferable to use a polymerization initiator in the suspension polymerization.
The polymerization initiator is not particularly limited, and includes, for example, benzoyl peroxide, lauroyl peroxide, methyl ethyl ketone peroxide, tert-butyl peroxybenzoate, cumene hydroperoxide, cyclohexanone peroxide, dicumyl peroxide, bis(4-tert -butylcyclohexyl) peroxydicarbonate; and azo compounds such as 2,2'-azobisisobutyronitrile and 2,2'-azobis-2-methylbutyronitrile. These may be used alone or in combination of two or more.
The amount and method of addition of the polymerization initiator may be appropriately set and is not particularly limited.

It is preferable to use a chain transfer agent in the suspension polymerization. By using a chain transfer agent, the polymerization reaction of monofunctional acrylic monomers can be easily controlled.
A thiol compound is preferably used as a chain transfer agent.
The thiol compound is not particularly limited, and includes, for example, alkyl mercaptans such as t-butyl mercaptan, n-octyl mercaptan, and n-dodecyl mercaptan; aromatic mercaptans such as thiophenol thionaphthol; thioglycolic acid, octyl thioglycolate, etc. Examples include alkyl thioglycolate.
The amount and method of addition of the chain transfer agent may be set appropriately and are not particularly limited.

In the second stage reaction, an esterification catalyst can be used to promote the reaction between the first functional group and the second functional group.
Examples of the esterification catalyst include amines such as triethylamine; quaternary ammonium salts such as tetraethylammonium chloride and tetrabutylammonium bromide; and phosphorus compounds such as triphenylphosphine. These may be used alone or in combination of two or more.
The amount of the esterification catalyst added may be set appropriately and is not particularly limited.

A polymerization inhibitor may be added in the second stage reaction. Addition of a polymerization inhibitor allows the second stage reaction to be carried out more stably.
Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, 2,6-di-t-butyl 4-methylphenol, and the like. These may be used alone or in combination of two or more.
The amount of the polymerization inhibitor added may be set appropriately and is not particularly limited.

The weight average molecular weight (Mw) of the first copolymer obtained in the first stage reaction is preferably within the range of 10,000 to 200,000, and preferably within the range of 20,000 to 170,000. It is preferably within the range of 30,000 to 100,000, and more preferably within the range of 30,000 to 100,000.
When the mass average molecular weight is at least the lower limit, the strength of the cured product tends to be sufficiently high. When the mass average molecular weight is below the upper limit, the workability when handling the resin composition will be good.
In addition, the mass average molecular weight in this specification is the molecular weight measured by gel permeation chromatography (hereinafter referred to as "GPC") after dissolving the polymer in a solvent (tetrahydrofuran), in terms of polystyrene.

The polymer (c-2) obtained in the second step reaction has a double bond, that is, the carboxy group contained in the first copolymer is converted into a glycidyl group of glycidyl (meth)acrylate by the second step reaction. This can be confirmed by the fact that the acid value of polymer (c-2) is lower than the value estimated from the (meth)acrylic acid used in the first stage reaction.
The acid value (unit: mgKOH/g) of the polymer (c-2) is preferably 1 or less, more preferably 0.5 or less.
The acid value value in this specification is a value determined by dissolving a polymer in toluene and titrating it with a 0.1N KOH ethanol solution using phenolphthalein as an indicator.

The content of the polymer (c-2) is preferably 1 to 20 parts by mass, and 5 to 15 parts by mass when the total of components (A), (B), and (C) is 100 parts by mass. part is more preferable. When the content of the polymer (c-2) is below the above upper limit, the resin composition can have a sufficient pot life, and the coating workability can be improved. On the other hand, when the content of the polymer (c-2) is at least the above lower limit, the viscosity of the resin composition can be balanced, the curability thereof can be improved, and the curing time can be appropriately shortened.

The content of the polymer (c-2) is within the above range (5 to 20 parts by mass) when the total of components (A), (B), and (C) is 100 parts by mass. , and more preferably within a range that satisfies the following formula (3). If the following formula (3) is satisfied, the viscosity of the resin composition does not become too high and coating workability can be maintained favorably.

300,000<Mw of polymer (c-2) x content of polymer (c-2)<1,400,000 (3)
In formula (3), "content of polymer (c-2)" refers to the content of polymer (c-2) when the total of component (A), component (B), and component (C) is 100 parts by mass. 2) content (parts by mass).

When the polymer (c-2) is a mixture of polymers (c-2-1), (c-2-2)..., the following formula (3') is used instead of the above formula (3). Use.

300,000<{Mw of polymer (c-2-1) x content of polymer (c-2-1)} + {Mw of polymer (c-2-2) x polymer (c-2) -2) Content}+...<1,400,000...(3')

The content of the polymer (C) is preferably 1 to 20 parts by mass, and 5 to 15 parts by mass when the total of components (A), (B), and (C) is 100 parts by mass. More preferred. When the content of the polymer (c-2) is below the above upper limit, the resin composition can have a sufficient pot life, and the coating workability can be improved. On the other hand, when the content of the polymer (C) is equal to or higher than the lower limit, the viscosity of the resin composition is balanced, the curability thereof can be improved, and the curing time can be appropriately shortened.
When the polymer (C) is a mixture of the polymer (c-1) and the polymer (c-2), it is preferably within a range that satisfies the following formula (4). If the following formula (4) is satisfied, the viscosity of the resin composition will not become too high and coating workability can be maintained favorably.

300,000<{Mw of polymer (c-1) x content of polymer (c-1)} + {Mw of polymer (c-2) x content of polymer (c-2)}< 1,400,000...(4)

<Wax (D)>
Wax (D) is a component for blocking air on the surface of the coating film during the curing reaction and improving surface curability. As the wax (D), one that does not dissolve in the components (A) and (B) can be used.
Specific examples of wax (D) include various known waxes such as paraffin wax and microcrystalline wax.
The melting point of wax (D) is preferably 40°C or higher, and preferably 120°C or lower. Two or more kinds of waxes having different melting points can also be used together.

As the wax (D), a wax (D) dispersed in an organic solvent may be used in order to improve surface curability. Since the wax (D) is dispersed in an organic solvent and made into fine particles, it can effectively exhibit an air blocking effect. A commercially available wax in this dispersed state can be used, and the resin composition can be prepared by adding the wax as it is. In this case, the resin composition will also contain an organic solvent.
The dispersed wax (D) may be one in which the wax is dispersed in the components (A) and (B) without containing any organic solvent.

The content of wax (D) is a total of 100 parts by mass of components (A), (B), (C), and (D) from the viewpoint of balance between air curability and physical properties of the coating film. 0.1 to 3 parts by mass, more preferably 0.1 to 2 parts by mass.
When the content of wax (D) is equal to or higher than the lower limit value, a sufficient air blocking effect can be obtained when the resin composition is coated and cured, and surface curability can be improved. If the content of wax (D) is below the above upper limit, the viscosity of the resin composition will not become too high, the curing speed and physical properties of the coating film will tend to be good, and the resin composition will be stable during storage. In addition, the stain resistance when the resin composition is coated and cured can be improved.

<Curing accelerator (E)>
The resin composition of the present invention preferably contains a curing accelerator (E).
Examples of the curing accelerator (E) include tertiary amines, organic metal compounds, and metal soaps.
Specific examples of tertiary amines include N,N-dimethylaniline, N,N-diethylaniline, N,N-dimethyl-p-toluidine, N,N-bis(2-hydroxyethyl)-p-toluidine, 4 -(N,N-dimethylamino)benzaldehyde, 4-[N,N-bis(2-hydroxyethyl)amino]benzaldehyde, 4-(N-methyl-N-hydroxyethylamino)benzaldehyde, N,N-bis( N,N-substituted anilines such as 2-hydroxypropyl)-p-toluidine, triethanolamine, diethylenetriamine, phenylmorpholine, N,N-bis(hydroxyethyl)aniline, diethanolaniline, N,N-substituted-p-toluidine , 4-(N,N-substituted amino)benzaldehyde, and the like.
One type of tertiary amine may be used alone, or two or more types may be used in combination.

Among the tertiary amines, aromatic tertiary amines are preferred. As the aromatic tertiary amine, one in which at least one aromatic residue is directly bonded to a nitrogen atom is preferable.
Examples of the aromatic tertiary amine include N,N-dimethyl-p-toluidine, N,N-diethylaniline, N,N-diethyl-p-toluidine, N-(2-hydroxyethyl)N-methyl-p- Toluidine, N,N-di(2-hydroxyethyl)-p-toluidine, N,N-di(2-hydroxypropyl)-p-toluidine; N,N-di(2-hydroxyethyl)-p-toluidine or Examples include ethylene oxide or propylene oxide adducts of N,N-di(2-hydroxypropyl)-p-toluidine. Further, instead of the p (para) body, the m (meta) body may be used.
Among aromatic tertiary amines, N,N-dimethyl-p-toluidine, N,N-diethyl-p-toluidine, N,N-di(2- Preferred are hydroxyethyl)-p-toluidine and N,N-di(2-hydroxypropyl)-p-toluidine.

The amount of curing accelerator such as tertiary amine added is determined based on the balance between curability and workability, based on a total of 100 parts by mass of components (A), (B), and (C). It is preferably 0.05 to 10 parts by weight, more preferably 0.2 to 8 parts by weight, and particularly preferably 0.3 to 5 parts by weight. If the amount of tertiary amine added is greater than or equal to the above lower limit, surface hardening properties can be improved, and if the amount is less than or equal to the above upper limit, an appropriate pot life can be achieved even at low temperatures.
Note that the preferable range of the amount of tertiary amine added varies depending on the type of curing accelerator used and the temperature environment, and it is preferable to adjust the amount added appropriately depending on the usage temperature.

Examples of the organometallic compound include organometallic compounds such as cobalt naphthenate, manganese naphthenate, nickel octylate, cobalt octylate, and cobalt acetoacetylate. Surface curability can be improved by adding these organometallic compounds to the resin composition.

The amount of organic metal compound or metal soap added is determined based on the total of 100 parts by mass of components (A), (B), and (C) from the viewpoint of balance between curability and workability. The content of metal derived from the compound is preferably 0.3 parts by mass or less, more preferably 0.2 parts by mass or less.
Note that the preferable range of the amount of the organometallic compound added varies depending on the type of curing accelerator used and the temperature environment, and it is preferable to adjust the amount added appropriately depending on the operating temperature. In addition, when there is a risk of impairing the transparency of the cured product, it is possible to include it to an extent that does not impair the transparency of the cured product.

The above curing accelerator may be added immediately before curing the resin composition, or may be added to the resin composition in advance.

<Curing agent>
When curing the resin composition, it is preferable to combine the curing accelerator with a curing agent to form a redox catalyst.
Examples of this curing agent include known curing agents that can initiate radical polymerization. Specific examples of such curing agents include ketone peroxide such as methyl ethyl ketone peroxide; 1,1-di(t-hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-di( Peroxyketals such as t-hexylperoxy)cyclohexane and 1,1-di(t-butylperoxy)cyclohexane; 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, p-menthane Hydroperoxides such as hydroperoxide; dialkyl peroxides such as dicumyl peroxide and di-t-butyl peroxide; diacyl peroxides such as dilauroyl peroxide and dibenzoyl peroxide; di(4-t-butylcyclohexyl) ) Peroxydicarbonates such as peroxydicarbonate and di(2-ethylhexyl)peroxydicarbonate; t-butylperoxy-2-ethylhexanoate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxy Examples include peroxy esters such as benzoate. The curing agents may be used alone or in combination of two or more.
Among the above curing agents, diacyl peroxide, peroxy ester and hydroperoxide are preferred, and benzoyl peroxide is particularly preferred.
From the viewpoint of ease of handling, benzoyl peroxide is preferably in the form of a liquid, paste, or powder diluted with an inert liquid or solid to a concentration of about 30 to 55% by mass.

The amount of curing agent added is preferably adjusted appropriately so that the pot life of the resin composition is 5 to 60 minutes. If the curing agent is added within this range, the polymerization reaction will start immediately after the addition, and the curing of the resin composition can proceed.
When benzoyl peroxide is used as a curing agent, the amount added is preferably 0.25 to 5 parts by mass based on the total of 100 parts by mass of components (A), (B), and (C). , more preferably 0.25 to 4 parts by mass. If the amount of benzoyl peroxide added is greater than or equal to the lower limit value, the curability will be good, and if it is less than the upper limit value, the coating workability of the resin composition and various physical properties of the resulting coating film will tend to improve. be. However, the amount of curing agent added is preferably adjusted appropriately depending on the operating temperature.

<Other additive components>
The resin composition of the present invention may optionally include other additive components such as oligomers, other polymer components, polymerization inhibitors, silane coupling agents, ultraviolet absorbers, light stabilizers, thixotropic agents, and reinforcing agents. Materials, plasticizers, isocyanate prepolymers, epoxy resins, aggregates, inorganic pigments such as chromium oxide and red iron, and organic pigments such as phthalocyanine blue can be used. Further, the resin composition may contain an antifoaming agent, a defoaming agent, a leveling agent, etc. as additive components for the purpose of improving coating workability and appearance.

[Oligomer]
The resin composition of the present invention may contain an oligomer having a (meth)acryloyl group in order to improve surface curability. Examples of the oligomer include at least one selected from the group consisting of urethane (meth)acrylate, epoxy (meth)acrylate, and polyester (meth)acrylate.

(Urethane (meth)acrylate oligomer)
As the urethane (meth)acrylate oligomer, for example, a polymer obtained mainly from a polyvalent isocyanate component (ua), a polyol component (ub), and a hydroxyl group-containing (meth)acrylate component (uc) is used. Can be mentioned.

As the polyvalent isocyanate component (ua), conventionally known and commonly used compounds having two or more isocyanate groups in the molecule can be used. Specific examples of such isocyanate compounds include aromatic isocyanates such as tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), and naphthalene diisocyanate (NDI); and isophorone diisocyanate (IPDI) and hexamethylene diisocyanate (HDI). Examples include aliphatic isocyanates; and the like. Further, triisocyanate compounds such as burette modified products and nurate modified products of isophorone diisocyanate and hexamethylene diisocyanate; mixtures of trivalent or higher polyvalent isocyanate compounds such as polymethylene polyphenyl polyisocyanate, and the like. These may be used alone or in combination of two or more.
Among the polyvalent isocyanate components (ua), tolylene diisocyanate (TDI) is particularly preferred from the viewpoint of ease of intentional molecular design during urethane (meth)acrylate synthesis.

As the polyol component (ub), conventionally known and commonly used compounds having divalent or higher alcoholic hydroxyl groups can be used. Specific examples include polyether polyols such as polytetramethylene ether glycol; polyester polyols such as reaction products of adipic acid and propylene glycol; polyacrylic polyols; and the like. These may be used alone or in combination of two or more.
As the polyol component (ub), polyester polyol is particularly preferred from the viewpoint of exhibiting flexibility.

The weight average molecular weight of the polyol component (ub) is preferably 400 or more from the viewpoint of exhibiting the intended flexibility. Further, from the viewpoint of easy balance between flexibility and curability, the weight average molecular weight of the polyol component (ub) is preferably 10,000 or less. Furthermore, the mass average molecular weight of the polyol component (ub) is more preferably 1,000 or more, and more preferably 3,000 or less.

In addition, in the related art, a chain extender is generally blended as part of the polyol that forms polyurethane. However, many chain extenders generally have low molecular weights, and due to the difference in reactivity between the polyol and the chain extender, the molecular weight of the oligomer produced may be uneven, and the desired polyol properties may be impaired. Therefore, in the present invention, it is not preferable to incorporate a chain extender.

Specific examples of the hydroxyl group-containing (meth)acrylate component (uc) include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl ( (Meth)acrylates having a hydroxyalkyl group such as meth)acrylate; γ-butyrolactone ring-opening adduct or ε-caprolactone ring-opening adduct to 2-hydroxyethyl (meth)acrylate, ethylene to (meth)acrylic acid A ring-opening adduct of oxide or a ring-opening adduct of propylene oxide, a dimer or trimer of 2-hydroxyethyl (meth)acrylate or 2-hydroxypropyl (meth)acrylate having a hydroxyl group at the end (meth) Acrylates; polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate; and the like. These may be used alone or in combination of two or more.
The hydroxyl group-containing (meth)acrylate component (uc) is 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, from the viewpoint of compatibility with other components in the resin composition and various physical properties. is preferred.

The weight average molecular weight of the urethane (meth)acrylate oligomer is preferably 1,000 or more, more preferably 5,000 or more, from the viewpoint of imparting good flexibility due to an appropriate distance between crosslinking points. From the viewpoint of improving coating workability, the weight average molecular weight of the urethane (meth)acrylate oligomer is preferably 50,000 or less.
Furthermore, the mass average molecular weight of the urethane (meth)acrylate oligomer is more preferably 5,000 or more, and more preferably 20,000 or less.

When synthesizing a urethane (meth)acrylate oligomer, the usage ratio of polyvalent isocyanate component (ua)/polyol component (ub) and hydroxyl group-containing (meth)acrylate component (uc) [(u-a) /((ub)+(uc))] is preferably set to a functional group molar ratio (NCO/OH) of 1/1. However, there is no particular problem even if it varies within the range of 1/0.95 to 0.95/1.

The method for synthesizing the urethane (meth)acrylate oligomer is not particularly limited. For example, an inert solvent is added to the polyvalent isocyanate component (ua), a catalyst (di-n-butyltin dilaurate, etc.) is added, and while the temperature is maintained at 40°C to 80°C, hydroxyl group-containing An example of this method is to sequentially drop the (meth)acrylate component (uc) and the polyol component (ub). Alternatively, an inert solvent and a catalyst may be added to the hydroxyl group-containing (meth)acrylate component (uc) and the polyol component (ub), and the polyvalent isocyanate component (ua) may be gradually added. .
As the inert solvent, for example, a (meth)acrylic acid alkyl ester having no hydroxyl group or the like can be used.

(Epoxy (meth)acrylate oligomer)
Epoxy (meth)acrylate is obtained by reacting a polybasic acid anhydride, a partially esterified product of hydroxyl group-containing (meth)acrylate, a bifunctional bisphenol A epoxy resin, and an unsaturated monobasic acid using a known method. It is something that can be done. Bifunctional bisphenol A type epoxy resin is a general-purpose epoxy resin made by reacting bisphenol A and epichlorohydrin.

(Polyester (meth)acrylate oligomer)
Polyester (meth)acrylate is obtained by reacting a polybasic acid or its anhydride, a polyhydric alcohol compound, and a (meth)acrylic acid adduct or glycidyl (meth)acrylate by a known method. Examples of polybasic acid anhydrides include phthalic acid, isophthalic acid, tetrahydrophthalic acid, succinic acid, maleic acid, fumaric acid, and adipic acid. Examples of polyhydric alcohols include ethylene glycol, propylene glycol, and the like.

(Amount of oligomer added)
In the resin composition of the present invention, the amount of oligomer added is preferably 10 parts by mass or less, and 5 parts by mass or less, based on a total of 100 parts by mass of components (A), (B), and (C). More preferred. When the amount of the oligomer added is below the above upper limit, the coating workability and various physical properties of the resulting coating film tend to improve without impairing the flexibility of the resin composition.

[Other polymer components]
The resin composition of the present invention may contain other polymers in addition to the polymer (C) and the oligomer. Other polymer components include vinyl chloride/vinyl acetate copolymers, epoxy resins, and the like, and the content thereof is preferably set to an extent that does not impair the transparency of the cured product.

[Polymerization inhibitor]
As the polymerization inhibitor, hydroquinone, 2-methylhydroquinone, hydroquinone monomethyl ether, 2,6-di-t-butyl 4-methylphenol, etc. are preferably added for the purpose of improving storage stability.

[Silane coupling agent]
The silane coupling agent is a silane coupling agent other than monomer (a4), such as γ-(glycidoxypropyl)trimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane. etc. A silane coupling agent can be used for the purpose of improving adhesion to inorganic substances.
The content of the silane coupling agent other than the monomer (a4) is preferably 5 parts by mass or less based on a total of 100 parts by mass of components (A), (B), and (C). From the viewpoint of cost, the amount is more preferably 3 parts by mass or less. If the content of the silane coupling agent is below the above upper limit, surface curability will be improved while improving the adhesion of the resin composition to the inorganic component.

[Ultraviolet absorber]
Ultraviolet absorbers are used to improve the weather resistance of coating films.
As ultraviolet absorbers, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-octyloxybenzophenone, 2-hydroxy-4-decyloxybenzophenone, 2-hydroxy-4,4'-dimethoxybenzophenone, 2-hydroxy-4 , 2-hydroxybenzophenone derivatives such as 4'-dibutoxybenzophenone, or 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3',5'-ditertiarybutyl) Examples include phenyl)benzotriazole, halides thereof, phenyl salicylate, and p-tert-butylphenyl salicylate. These may be used alone or in combination of two or more.

[Light stabilizer]
As light stabilizers, bis(2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 1-[2-[ 3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy]ethyl]-4-[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxy]-2 , 2,6,6-tetramethylpiperidine, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, and the like. These may be used alone or in combination of two or more.

[Thixotropic agent]
The thixotropic agent imparts thixotropy to the resin composition. Specifically, containing a thixotropic agent imparts structural viscosity to the resin composition, increases thixotropy, enables uniform distribution of additives in the resin composition, and improves storage stability of the resin composition. will improve. Further, by containing a thixotropic agent, it is possible to improve the coating workability when applying the resin composition to an inclined surface, for example.
As the thixotropic agent, organic thixotropic agents such as urethane urea, fatty acid amide, organic bentonite, and oxidized polyethylene wax, and fine silica are preferable. One type of thixotropic agent may be used alone, or two or more types may be used in combination.
A plurality of thixotropic agents can be used in combination. Combinations of thixotropic agents include combinations of fatty acid amide and fine-grained silica, combinations of organic bentonite and fine-grained silica, combinations of fatty acid amide, organic bentonite and fine-grained silica, and combinations of oxidized polyethylene wax and fine-grained silica.
The average primary particle diameter of the fine silica particles is preferably 7 to 40 μm.
The content of the thixotropic agent is a total of 5 parts by mass or less of urethane urea, fatty acid amide, and/or organic bentonite per 100 parts by mass of components (A), (B), and (C). It is preferable that the amount of fine silica is 10 parts by mass or less.
If the content of the thixotropic agent is too high, the fluidity of the resin composition will decrease, and the coating workability will decrease, so that it may not be possible to obtain a uniform coating film. From these viewpoints, it is preferable to set the content within the above range in order to suppress fluidity when applying it to an inclined surface.

[Reinforcement material]
The reinforcing material is preferably used when the flexibility and tensile elongation at break of the resin composition are excessive for the usage situation.
Examples of the reinforcing material include chopped strands, roving net-like glass fibers, vinylon fibers, nylon fibers, and the like. One type of reinforcing material may be used alone, or two or more types may be used in combination.

[Plasticizer]
The plasticizer is used to reduce shrinkage during curing.
Examples of plasticizers include phthalic acid esters such as dibutyl phthalate, di-2-ethylhexyl phthalate, and diisodecyl phthalate, adipic acid esters such as di-2-ethylhexyl adipate and octyl adipate, dibutyl sebacate, and di-2-ethylhexyl sebacate. Sebacic acid esters such as cate, alkyl sulfonic acid esters such as alkyl sulfonic acid phenyl ester, cyclohexanedicarboxylic acid dialkyl esters such as 1,2-dicyclohexanedicarboxylic acid diisononyl ester, di-2-ethylhexyl azelate, octyl aze dibasic fatty acid esters such as azelain esters; paraffins such as chlorinated paraffins; and paraffins such as chlorinated paraffins. One type of plasticizer may be used alone, or two or more types may be used in combination.
The content of the plasticizer is preferably 10 parts by mass or less with respect to a total of 100 parts by mass of components (A), (B), and (C). When the content of the plasticizer is 10 parts by mass or less, the mechanical strength of the coating film can be sufficiently ensured, and the plasticizer can be prevented from exuding onto the surface of the coating film.

[Defoaming agent]
Examples of the antifoaming agent include known antifoaming agents. Specifically, acrylic antifoaming agents prepared by dissolving a special acrylic polymer in a solvent, vinyl antifoaming agents prepared by dissolving a special vinyl polymer in a solvent, etc. can be mentioned. Among antifoaming agents, the Disparon series (product names: OX-880EF, OX-881, OX-883, OX-77EF, OX-710, OX-8040, 1922, 1927, More preferably, , among the Disparon series, 230, 230EF, LF-1980, and LF-1985 are more preferred, and 230EF and LF-1985 are particularly preferred. Furthermore, BYK-052N and BYK-1752 commercially available from BYK Chemie Japan Co., Ltd. can also be used. One type of antifoaming agent may be used alone, or two or more types may be used in combination.
The content of the antifoaming agent is preferably 3 parts by mass or less, more preferably 2 parts by mass or less, based on a total of 100 parts by mass of components (A), (B), and (C). If it is below the above upper limit, air bubbles mixed in when the resin composition is stirred and mixed can be effectively removed, and a coating film without air bubbles can be obtained.

[Isocyanate prepolymer]
Isocyanate prepolymers have high reactivity and easily react with moisture in the air and monomer components in the resin composition. Therefore, if the acrylic resin composition contains an isocyanate prepolymer, the curing time can be further shortened.
Examples of the isocyanate prepolymer include hexamethylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, diphenylmethane-4,4'-diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, and tetramethylene. Examples include polyisocyanurates prepared by prepolymerizing diisocyanate, phenylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, isophorone diisocyanate, and the like. The isocyanate prepolymers may be used alone or in combination of two or more.
The content of the isocyanate prepolymer is preferably 30 parts by mass or less based on a total of 100 parts by mass of components (A), (B), and (C). When the content of the isocyanate prepolymer is at most the above upper limit, the curing time can be further shortened while ensuring a sufficient pot life of the resin composition, resulting in good workability.

[Epoxy resin]
Epoxy resin is a component that improves adhesiveness with inorganic substrates. Therefore, if the resin composition contains an epoxy resin, good adhesion to concrete, crushed stone used in asphalt pavement, etc. can be achieved.
Examples of the epoxy resin include bisphenol A epoxy resin, bisphenol F epoxy resin, biphenyl epoxy resin, dicyclopentadiene epoxy resin, and polysulfide modified epoxy resin.
As the epoxy resin, a polysulfide-modified epoxy resin is preferable from the viewpoint of adhesiveness with the inorganic base material and curability. Epoxy resins may be used alone or in combination of two or more.
The content of the epoxy resin is preferably 20 parts by mass or less, more preferably 10 parts by mass or less, based on a total of 100 parts by mass of components (A), (B), and (C). When the content of the epoxy resin is at most the above upper limit, the curing time can be shortened while ensuring a sufficient pot life of the resin composition, resulting in good workability.

[thiol compound]
The radically polymerizable resin composition of the present invention may contain a thiol compound having one or more thiol groups such as aliphatic thiol and aromatic thiophenol. When a radically polymerizable resin composition is formed into a thin film and cured, the curability may decrease due to the influence of oxygen in the air, but the curability may be improved by adding a thiol compound.
As the thiol compound, aliphatic thiols are preferred. As the thiol compound, any of primary thiol compounds, secondary thiol compounds, and tertiary thiol compounds can be used. From the viewpoint of improving curability, polyfunctional thiols having two or more primary or secondary thiol groups are preferred, and polyfunctional thiols having three or more primary or secondary thiol groups are more preferred. Note that a polyfunctional thiol is a thiol compound having two or more thiol groups, and an n-functional thiol is a thiol compound having n thiol groups.

Specific examples of primary thiol compounds include bifunctional thiols such as tetraethylene glycol bismercaptoacetate and tetraethylene glycol bis(3-mercaptopropionate); trimethylolethane tris(3-mercaptopropionate), and trimethylol. Propane tris-mercaptoacetate, trimethylolpropane tris (3-mercaptopropionate), trimethylolpropane tris (4-mercaptobutyrate), tris-[(3-mercaptopropionyloxy)-ethyl]-isocyanurate, tris-[ Trifunctional thiols such as (3-mercaptobutyryloxy)-ethyl]-isocyanurate, glycerol tris-(3-mercaptopropionate), glycerol tris-(4-mercaptobutyrate); pentaerythritol tetramercaptoacetate, pentaerythritol tetramercaptoacetate, Tetrafunctional thiols such as erythritol tetrakis (3-mercaptopropionate), pentaerythritol tetrakis (4-mercaptobutyrate); dipentaerythritol hexamercaptoacetate, dipentaerythritol hexakis (3-mercaptopropionate), dipentaerythritol hexakis (3-mercaptopropionate), etc. Examples include polyfunctional thiols exceeding tetrafunctionality such as erythritol hexakis (4-mercaptobutyrate).

Specific examples of secondary thiol compounds include monofunctional thiols such as 3-mercaptobutyric acid; ethylene glycol bis(3-mercaptobutyrate), propylene glycol bis(3-mercaptobutyrate), diethylene glycol bis(3-mercaptobutyrate); ), tetraethylene glycol bis(3-mercaptobutyrate), butanediol bis(3-mercaptobutyrate), octanediol bis(3-mercaptobutyrate), ethylene glycol bis(2-mercaptopropionate), propylene glycol Bis(2-mercaptopropionate), diethylene glycol bis(2-mercaptopropionate), butanediol bis(2-mercaptopropionate), octanediol bis(2-mercaptopropionate), ethylene glycol bis(4-mercaptopropionate) -mercaptovalerate), diethylene glycol bis(4-mercaptovalerate), butanediol bis(4-mercaptovalerate), octanediol bis(4-mercaptovalerate), ethylene glycol bis(3-mercaptovalerate), propylene Glycol bis(3-mercaptovalerate), diethylene glycol bis(3-mercaptovalerate), butanediol bis(3-mercaptovalerate), octanediol bis(3-mercaptovalerate), hydrogenated bisphenol A bis(3-mercaptovalerate) mercaptobutyrate), bisphenol A dihydroxyethyl ether-3-mercaptobutyrate, ethylene glycol bis(3-mercapto-3-phenylpropionate), propylene glycol bis(3-mercapto-3-phenylpropionate), diethylene glycol bis( Difunctional thiols such as 3-mercapto-3-phenylpropionate), butanediol bis(3-mercapto-3-phenylpropionate), octanediol bis(3-mercapto-3-phenylpropionate); trimethylolethane tris (3-mercaptobutyrate), trimethylolpropane tris(3-mercaptobutyrate), trimethylolpropane tris(2-mercaptopropionate), 1,4-bis(3-mercaptobutyryloxy)butane, 1, 3,5-tris[2-(3-mercaptobutyryloxyethyl)]-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, trimethylolpropane tris(4-mercapto valerate), tris-[(3-mercaptobutyryloxy)-ethyl]-isocyanurate, trimethylolpropane tris(3-mercaptovalerate), trimethylolpropane tris(3-mercapto-3-phenylpropionate), Trifunctional thiols such as tris-2-(3-mercapto-3-phenylpropionate) ethyl isocyanurate; pentaerythritol tetrakis (3-mercaptobutyrate), pentaerythritol tetrakis (2-mercaptopropionate), pentaerythritol Tetrafunctional thiols such as tetrakis (4-mercaptovalerate), pentaerythritol tetrakis (3-mercaptovalerate), pentaerythritol tetrakis (3-mercapto-3-phenylpropionate); dipentaerythritol hexakis (3-mercaptobutylpropionate); ), dipentaerythritol hexakis (2-mercaptopropionate), dipentaerythritol hexakis (4-mercaptovalerate), dipentaerythritol hexakis (3-mercaptovalerate), dipentaerythritol hexakis (3-mercaptovalerate) -mercapto-3-phenylpropionate);

Among them, 1,4-bis(3-mercaptobutyryloxy)butane, 1,3,5-tris[2-(3-mercaptobutyryloxyethyl)]-1,3,5-triazine-2, 4,6(1H,3H,5H)-trione, trimethylolethane tris (3-mercaptobutyrate), trimethylolpropane tris (3-mercaptobutyrate), pentaerythritol tetrakis (3-mercaptobutyrate), etc. are preferred. , it is preferable to use one or more of these.
The molecular weight of the thiol compound is preferably 200 to 1,000.

The amount of the thiol compound to be blended is preferably 0.05 to 2 parts by weight, more preferably 0.1 to 1.5 parts by weight, based on a total of 100 parts by weight of components (A) and (B). The larger the amount of the thiol compound, the better the curability of the resin composition when it is cured into a thin film. On the other hand, since thiol compounds are relatively expensive, the smaller the amount of thiol compounds incorporated, the more economical the resin composition tends to be.
One type of thiol compound may be used alone, or two or more types may be used in combination. A primary thiol compound and a secondary thiol compound may be used in combination.

[aggregate]
The resin composition of the present invention may contain aggregate. Aggregate is a component that imparts strength to the coating film obtained from the resin composition.
Examples of aggregates include natural inorganic ores such as sand, silica sand, river sand, kansui stone, emery, and marble, alumina, slag, glass, ceramic aggregates, pottery, porcelain, tiles, glass beads, colored aggregates, calcium carbonate, Examples include silica fume, fly ash, talc, clay, titanium oxide, aluminum hydroxide, and the like. One type of aggregate may be used alone, or two or more types may be used in combination.
Furthermore, when transparency of the cured product is required, natural inorganic ores such as sand, silica sand, river sand, kansui stone, emery, marble, alumina, slag, glass, ceramic aggregates, pottery, porcelain, tiles, glass beads, etc. The material may be appropriately selected from among colored aggregates and the like.
When blending aggregate, the aggregate content is preferably 100 to 800 parts by mass, more preferably 150 to 700 parts by mass, based on 100 parts by mass of the resin composition of the present invention. When the amount of aggregate is 100 parts by mass or more, sufficient strength can be imparted to the coating film, and the shape stability of the coating film can be maintained well. On the other hand, if the aggregate content is 800 parts by mass or less, the coating workability of the resin composition can be maintained favorably.

<Method for manufacturing resin composition>
Examples of the method for producing the resin composition include a method of mixing the components described above.
In addition, among the curing accelerators (E), the tertiary amine may be added immediately before curing the resin composition, or may be added to the resin composition in advance. When using an organometallic compound as the curing accelerator (E), it is preferably added immediately before curing the resin composition. If an organometallic compound is added to a resin composition in advance, the stability of the resin composition may decrease, and the viscosity of the resin composition may increase over time or the resin composition may gel.
Further, the curing agent is preferably added immediately before curing the resin composition.

<Effect>
The resin composition of the present invention described above contains the monomer (A), the monomer (B), the polymer (C), and the wax (D), and as the monomer (A), By containing (meth)acrylate (a1) having an aromatic ring, hydroxyalkyl (meth)acrylate (a2), and (meth)acrylate (a3) whose homopolymer Tg is -10°C or lower, odor can be eliminated. It can be suppressed. Moreover, the resin composition of the present invention has excellent curability and can easily form a cured coating film with little turbidity. Therefore, it can be applied to highly decorative coating methods that take advantage of the texture of stones and aggregates.
The resin composition of the present invention is suitable as a coating agent for floors such as concrete and asphalt, walls, paved surfaces of roads, and the like.

"Laminated body"
The laminate of the present invention includes a base material and a coating film made of a cured product of the resin composition of the present invention formed on the surface of the base material. The laminate can be obtained by applying the resin composition of the present invention to a base material and curing it to form a cured product.

Examples of the base material in the laminate include cement concrete, asphalt concrete, mortar concrete, resin concrete, permeable concrete, ALC (lightweight foamed concrete) board, PC (precast concrete) board, and the like. These may be used alone or in combination of two or more to form a base material. Concrete may or may not contain reinforcing steel.
These base materials are used, for example, for floor slabs of buildings, platforms, roads, bridges, viaducts, and the like. For building floors, platforms, and floor slab structures, it may be used as a building flooring material on which a coating film has already been formed, an existing base material on which a paving layer has been formed, or the base material in the present invention. Moreover, the structure after peeling off the existing pavement layer or the existing waterproofing layer may be used as a base material before coating the undercoat layer.
The shape of the base material is not particularly limited, and may be any shape, such as a flat surface, a curved surface, or an inclined surface.

The thickness of the coating film is not particularly limited, and is determined depending on, for example, the functionality required of the laminate.
Examples of the method for forming the coating film include a method in which the resin composition of the present invention is applied to a substrate and then cured.
Examples of the coating method include known coating methods using a roller, a metal trowel, a brush, a flexible brush, a coating machine (such as a spray coating machine), and the like. When using a two-component airless atomizer, separate the two components into a main agent side and a curing agent side, add a curing accelerator to the main agent side, and add, for example, an organic peroxide as a curing agent to the curing agent side. The method is preferred.

Further, the temperature during coating is preferably -20 to 60°C, particularly preferably -10 to 40°C. From the viewpoint of workability, the pot life is preferably 5 to 90 minutes, more preferably 5 to 60 minutes. The curing time is preferably 10 to 120 minutes, more preferably 10 to 90 minutes. Pot life and curing time are controlled by adjusting the amount of organic peroxide curing agent and curing accelerator.

In the laminate of the present invention, it is sufficient that a coating film, which is a cured product of the resin composition of the present invention, is formed on the surface of the base material. For example, a coating film that is a cured product of the resin composition of the present invention may be formed as an undercoat layer, and an intermediate coat layer and a top coat layer may be laminated in this order on this undercoat layer. In addition, the laminate may have only an undercoat layer formed on the surface of the base material, only an undercoat layer and a topcoat layer, or a laminate of four or more layers including the undercoat layer. may have been done.
The viscosity of the resin composition forming the undercoat layer is preferably a solution viscosity of 50 to 400 mPa·s measured at 23° C. using a Brookfield viscometer (60 rpm) specified in JIS-Z8803.

When forming an intermediate coat layer on the surface of the undercoat layer, the intermediate coat layer is not particularly limited, and may be a layer made of a cured product of the resin composition of the present invention, or a layer made of a cured product other than the resin composition of the present invention. It may be a layer.
Materials for forming an intermediate coating layer other than the resin composition of the present invention include synthetic resin paints that are cured after application, such as solvent-based resins, emulsion-based resins, epoxy resins, polyurethane resins, unsaturated polyester resins, and methacrylic resins. Examples include solid materials such as resin, rubber, asphalt, etc., which are melted and liquefied before coating), and liquid materials such as petroleum asphalt, asphalt emulsion, and various liquid synthetic resins.
The method for forming the intermediate coat layer is appropriately determined depending on the type of material that constitutes the intermediate coat layer.
Among the intermediate coating layers, a layer made of a cured product of the resin composition of the present invention is preferred, and a layer made of a cured product of the resin composition of the present invention containing aggregate is particularly preferred.
The viscosity of the resin composition forming the intermediate coating layer is preferably a solution viscosity of 50 to 400 mPa·s, preferably 50 to 300 mPa, as measured by a Brookfield viscometer (60 rpm) specified in JIS-Z8803 at 23°C. - It is more preferable that it is s.
In addition, the resin composition forming the intermediate coating layer has a cured product having a maximum tensile strength of 4 N/mm ² or more and a tensile elongation at break measured at 23°C according to the measuring method specified in JIS K6251:2010. It is preferable that the degree is 130% or more.

When forming a top coat layer on the surface of the intermediate coat layer, the same layer as the intermediate coat layer can be used as the top coat layer. Further, the top coat layer may be a top coat layer or a protective layer formed of a film or sheet from the viewpoint of design and appearance.
The viscosity of the resin composition forming the topcoat layer is preferably a solution viscosity of 100 to 400 mPa·s measured at 23° C. using a Brookfield viscometer (60 rpm) specified in JIS-Z8803.
Further, the cured product of the resin composition forming the top coat layer preferably has a maximum tensile strength of 10 N/mm ² or more when measured at 23° C. according to the measuring method specified in JIS K6251:2010.

The laminate of the present invention has a coating film made of a cured product of the resin composition of the present invention formed on the surface of a substrate, and the coating film is highly transparent with little turbidity. Therefore, the laminate of the present invention can easily take advantage of the texture of stone and aggregate, and has a high design quality.

The present invention will be specifically described below with reference to Examples. Note that the present invention is not limited to the following examples.
In the following examples, all "parts" indicate "parts by mass", and all "%" except for the degree of saponification and humidity indicate "% by mass".

[Synthesis Example 1: Synthesis of polymer (P-1)]
In a polymerization apparatus equipped with a stirrer, a cooling tube, and a thermometer, 135 parts of deionized water and 0.4 parts of polyvinyl alcohol (saponification degree 80 mol%, polymerization degree 1,700) as a dispersant were added and stirred. After the polyvinyl alcohol was completely dissolved, stirring was temporarily stopped. 100 parts of methyl methacrylate (hereinafter abbreviated as "MMA"), 0.2 part of 2,2'-azobis-2-methylbutyronitrile (hereinafter abbreviated as "AMBN") as a polymerization initiator, and n-dodecyl as a chain transfer agent. 0.8 part of mercaptan (hereinafter abbreviated as "n-DM") and 0.1 part of sodium carbonate as an electrolyte were added, stirred again, heated to 75° C., and reacted for 2.5 hours. Further, the temperature was raised to 98°C and maintained for 1.5 hours, and then the reaction was terminated.
Then, after cooling to 40°C, the resulting aqueous suspension was filtered through a nylon filter cloth with an opening of 45 μm, and the filtrate was washed with deionized water, dehydrated, and then dried at 40°C for 16 hours. As a result, a granular vinyl polymer (P-1) (hereinafter abbreviated as "P-1") was obtained.
The glass transition temperature (Tg) of the obtained P-1 was 100°C, and the mass average molecular weight was 40,000.
The Tg of the particulate vinyl polymer was calculated from the Tg of the homopolymer described in the Polymer Handbook using the Fox formula.

[Synthesis Example 2: Synthesis of polymer (P-2)]
In the reaction of Synthesis Example 1, the amount of MMA used was changed from 100 parts to 80 parts, 20 parts of n-butyl acrylate (hereinafter abbreviated as "n-BMA") was added, and the amount of n-DM used was changed to 0. Changed from 8 parts to 0.35 parts. Except for the above, a granular vinyl polymer (P-2) (hereinafter abbreviated as "P-2") having a Tg of 82° C. and a mass average molecular weight of 80,000 was obtained in the same manner as in Synthesis Example 1.

[Synthesis Example 3: Synthesis of polymer (P-3)]
In the reaction of Synthesis Example 1, the amount of MMA used was changed from 100 parts to 40 parts, the amount of n-BMA used was changed to 60 parts, and the amount of n-DM used was changed from 0.8 parts to 0.5 parts. Changed to Except for the above, a granular vinyl polymer (P-3) (hereinafter abbreviated as "P-3") having a Tg of 49° C. and a mass average molecular weight of 60,000 was obtained in the same manner as in Synthesis Example 1.

<Preparation of resin composition>
[Example 1: Resin composition (S-1)]
In a 1 L flask equipped with a stirrer, thermometer, and cooling tube, 53.0 parts of phenoxyethyl methacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name: Light Ester PO) as the monomer (A), and 2-hydroxypropyl methacrylate (hereinafter referred to as 10 parts of methoxydiethylene glycol monomethacrylate (manufactured by NOF Corporation, trade name: Blenmar PME-100 (hereinafter referred to as "PME-100")), 10 parts of 2-ethylhexyl acrylate (hereinafter referred to as "2-HPMA"), -EHA") and 5.0 parts of polypropylene glycol dimethacrylate (manufactured by NOF Corporation, trade name: Blenmar PDP-400N (hereinafter abbreviated as "PDP-400N")) as the monomer (B). , 0.12 parts of 2,6-di-t-butyl 4-methylphenol (hereinafter abbreviated as "BHT") as a light stabilizer, and paraffin-130 (manufactured by Nippon Seiro Co., Ltd., paraffin) as wax (D). wax (hereinafter abbreviated as "P-130")) 0.4 part, and paraffin-150 (manufactured by Nippon Seiro Co., Ltd., paraffin wax (hereinafter abbreviated as "P-150")) 0.3 part, HNP-9 (manufactured by Nippon Seiro Co., Ltd., paraffin wax (hereinafter referred to as "HNP-9")) 0.3 parts, antifoaming agent (manufactured by Kusumoto Kasei Co., Ltd., trade name: Disparon 230EF) 0.5 parts, and hardening acceleration 0.6 part of N,N-di(2-hydroxyethyl)-p-toluidine (hereinafter abbreviated as "PTEO") as the agent (E) and JF-77 (manufactured by Johoku Kagaku Co., Ltd.) as an ultraviolet absorber (hereinafter "PTEO"). After adding 0.2 parts of ``JF-77''), 12.0 parts of P-1 as polymer (C) was added while stirring.Subsequently, it was heated at 75°C for 2 hours to dissolve. After confirming dissolution, it was cooled to obtain a resin composition (S-1). Table 1 shows the blending composition of the obtained resin composition (S-1).

[Examples 2 to 4, 6 to 9 , Reference Example 5 : Preparation of resin compositions (S-2) to (S-9)]
Resin compositions (S-2) to (S-9) were obtained in the same manner as in Example 1, except that the blending composition was changed to the composition shown in Table 1.

[Comparative Examples 1 to 4, 8: Preparation of resin compositions (S-10) to (S-13), (S-17)]
Resin compositions (S-10) to ( S-13) and (S-17) were obtained in the same manner as in Example 1, except that the blending composition was changed to the composition shown in Table 2.
In Tables 1 and 2, "PHMA" is phenyl methacrylate, "BZMA" is benzyl methacrylate, "ETMA" is 2-ethoxyethyl methacrylate (manufactured by Mitsubishi Chemical Corporation, product name: Acryester ET), "New Frontier BPE"-4" is ethylene oxide-modified bisphenol A diacrylate (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: New Frontier BPE-4), and "Additive 1" is pentaerythritol tetrakis (3-mercaptopropylene), a primary thiol compound. "Additive 2" represents pentaerythritol tetrakis (3-mercaptobutyrate), which is a secondary thiol compound.

(viscosity)
The viscosity of the resin composition of each example was measured by the following measuring method. The results are shown in Tables 1 and 2.
The viscosity at 23±1° C. (viscosity at 60 rpm) was measured using a B-type (Brookfield-type) viscometer (BM type, manufactured by Tokimec Co., Ltd.).
(TI value)
The TI value (thixotropic index) of the resin composition of each example was measured by the following measuring method. The results are shown in Tables 1 and 2.
According to the method specified in JIS-K6833, when the temperature of the composition is 23 ± 1 ° C., the viscosity is measured using a B-type viscometer (BM type, manufactured by Tokimec Co., Ltd.) according to the following formula (5). I asked for it.
TI value = [Viscosity at a rotation speed of 6 rpm (mPa・s)]/[Viscosity at a rotation speed of 60 rpm (mPa・s)] ... (5)

<Performance evaluation>
A resin composition containing a curing agent was prepared as described below, and its curing properties, tensile test, workability, odor, adhesiveness, and transparency were measured or evaluated. The results are shown in Tables 1 and 2.

[Curing characteristics (23°C)]
Samples for measuring curing characteristics at 23°C were prepared as follows.
To 100 parts of the resin composition of each example, 3 parts of a curing agent (product name: Nyper NS, manufactured by NOF Corporation, 40% benzoyl peroxide product) (hereinafter abbreviated as "Nyper NS") was added, and enough By mixing, a resin composition containing a curing agent was obtained.

(gelling time)
In a variable environment room with an indoor temperature of 23 ° C. and a humidity of 50%, 50 g of the above-mentioned resin composition containing a curing agent was poured into a 100 ml polypropylene cup, and the time from the addition of the curing agent until the resin lost its fluidity was measured. This time was defined as gelation time.
(Drying time)
The above resin composition containing a curing agent was applied onto a polyethylene terephthalate film to a thickness of 300 μm using an applicator in a variable environment room with an indoor temperature of 23° C. and a humidity of 50%. Thereafter, the time required for the coating film to dry was measured, and this time was defined as the drying time. The completion of drying of the coating film was defined as the point in time when the gauze no longer stuck to the coating film when the gauze was brought into contact with the surface of the obtained coating film.

[Curing properties (0°C)]
A sample for measuring curing characteristics at 0°C was prepared as follows.
For 100 parts of the resin composition of each example, 1 part of AC-150 (product name Acrysilap AC-150, manufactured by Ryoko Co., Ltd.) (hereinafter abbreviated as "AC-150") as a curing accelerator, and as a curing agent Six parts of Niper NS was added and thoroughly mixed to obtain a curing agent-containing resin composition.
(gelling time)
In a constant temperature and humidity chamber controlled at 0°C, 50g of the above-mentioned resin composition containing a curing agent was put into a 100ml polypropylene cup, and the time from the addition of the curing agent until the resin lost its fluidity was measured. was taken as the gelation time.
(Drying time)
In a constant temperature and humidity chamber controlled at 0° C., the above resin composition containing a curing agent was applied onto a polyethylene terephthalate film to a thickness of 300 μm using an applicator. Thereafter, the time required for the coating film to dry was measured, and this time was defined as the drying time. Completion of drying of the coating film was defined as the point in time when the gauze no longer stuck to the coating film when the gauze was brought into contact with the surface of the obtained coating film.

[Tensile test]
The resin composition containing a curing agent was poured into a mold, cured, and cured in a variable environment room with an indoor temperature of 23° C. and a humidity of 50%. The next day after curing, a cast plate (test sample) with a thickness of 3 mm was obtained.
These test samples were subjected to a tensile test at 23° C. in accordance with JIS-K6251:2010, and the tensile strength at break (N/mm ² ) was measured. This tensile breaking strength is one of the indicators of the mechanical strength of a cured coating film. In the tensile test, tensile elongation at break was also measured.

[Odor]
The resin composition of each example and the base material (slate board, 90 cm x 90 cm x 5 mm thickness) were placed in a variable environment room with an indoor temperature of 23°C and a relative humidity of 50%. (3 m x 7 m x height 3 m) for more than 4 hours, and the temperature was adjusted to be the same as that of the variable environment room. Thereafter, a curing agent Niper NS was added to the resin composition, and the resin composition was coated on the surface of the substrate in the variable environment chamber at a coating amount of about 0.3 kg/m ² . Five evaluators were present during this painting operation and evaluated the odor at a position 50 cm away from the coating surface using the following criteria.
○: All five people did not feel any odor.
△: 1 to 4 people felt the smell.
×: All five people felt the smell.

[Workability]
The resin composition of each example and a JIS mortar board (30 cm x 30 cm x 6 cm thickness) were placed in a variable environment room (3 m x 7 m x height 3 m) for more than 4 hours, and the temperature was adjusted to be the same as the temperature of the variable environment room. After that, the hardening agent Niper NS was added to the resin composition, and the coating workability was evaluated when the coating amount was about 0.3 kg/m ² on the surface of the substrate in the variable environment chamber using a wool roller. Evaluation was made based on the following evaluation criteria.
Good: No coating unevenness occurred, and the result was good.
×: Coating unevenness occurred.

[Adhesiveness]
The resin composition was applied in the same manner as in the evaluation of painting workability, and 24 hours after curing, the adhesion was evaluated as follows according to the coating floor adhesion strength test method (NNK-005:2006) of the Japan Coating Floor Industry Association test method. It was evaluated based on the following criteria.
Good: 80% or more of the area had cohesive failure of the base material or cohesive failure of the coating film.
×: The area in which cohesive failure of the base material or cohesive failure of the coating film (including delamination between the base material and the coating film) occurred was less than 80%.

[transparency]
The resin composition containing a curing agent was cured and cured in a variable environment room with an indoor temperature of 23° C. and a humidity of 50%. A cured resin product with a thickness of 3 mm was obtained the day after curing.
The total light transmittance (%) of the cured resin product was measured according to JIS-K7105. For the measurement, a haze meter (Model HM-150, manufactured by Murakami Color Research Institute Co., Ltd.) was used. Transparency was evaluated based on the measured total light transmittance based on the following criteria.
○: Total light transmittance was 75.0% or more.
Δ: Total light transmittance was 50.0% or more and less than 75.0%.
×: Total light transmittance was less than 50.0%.

As shown in Table 1, Examples 1 to 4 , which are within the scope of the present invention, have good workability because the resin viscosity is within the preferred range, and the curing characteristics and drying time are within the appropriate range. , the odor was weak, and the transparency and adhesiveness were also good.

On the other hand, as shown in Table 2, Comparative Example 1 (resin composition S-10) has good workability because the resin viscosity is within the preferred range, and the curing characteristics and drying time are also appropriate. Although the odor was within the range and the odor was weak, the cured product of the resin composition had low transparency.
Comparative Example 2 (resin composition S-11) has good workability because the resin viscosity is within a preferable range, and the curing characteristics and drying time are within appropriate ranges, but it has a strong odor and The result was that the cured product of the resin composition had low transparency.
Comparative Example 3 (resin composition S-12) has good workability because the resin viscosity is within a preferable range, and the curing characteristics and drying time are within appropriate ranges, and the cured product of the resin composition is Although the transparency was high, the result was a strong odor.
Comparative Example 4 (resin composition S-13) has good workability because the resin viscosity is within the preferred range, the drying time is within the appropriate range, the odor is weak, and the cured product of the resin composition is Although the coating had high transparency, both the tensile strength and tensile elongation at break were low in the tensile test, and the coating film was extremely brittle .
Comparative Example 8 (resin composition S-17) has good workability because the resin viscosity is within a preferable range, has a weak odor, and has good transparency, but the drying time exceeds 60 minutes. It became.

The resin composition of the present invention has low odor, excellent curability, and can provide a cured coating film with little turbidity. Therefore, it can be easily applied to a decorative coating method that takes advantage of the texture of stone or aggregate.

Claims (3)

(a1): (meth)acrylate monomer having an aromatic ring, (a2): hydroxyalkyl (meth)acrylate, and (a3): (meth)acrylate whose homopolymer Tg is -10°C or less (provided that the above ( ( excluding a1 ) and (a2) . The content of mer (a3) is 5 to 25 parts by mass, the content of hydroxyalkyl (meth)acrylate (a2) is 10 to 25 parts by mass , and one (meth)acryloyl group is present in the molecule. a monomer (A) having two or more (meth)acryloyl groups in the molecule, a polymer (C) having 60% by mass or more of methyl methacrylate units, and a wax (D). ) and
The content of the polymer (C) is 1 to 20 parts by mass when the total of the monomer (A), the monomer (B), and the polymer (C) is 100 parts by mass. and the content of the wax (D) is based on a total of 100 parts by mass of the monomer (A), the monomer (B), the polymer (C), and the wax (D). , 0.1 to 3 parts by mass,
As the monomer (A), a (meth)acrylate (a1) having an aromatic ring that is at least one selected from the group consisting of phenyl (meth)acrylate and phenoxyethyl (meth)acrylate;
hydroxyalkyl (meth)acrylate (a2),
An acrylic resin composition containing (meth)acrylate (a3) whose homopolymer glass transition temperature (Tg) is -10°C or lower. (However, this excludes cases where the monomer (a3) is any of ethyl acrylate, acrylic acid, n-butyl acrylate, i-butyl acrylate, and t-butyl acrylate.) According to claim 1, the polymer (C) is contained in 1 to 20 parts by mass based on a total of 100 parts by mass of the monomer (A), the monomer (B), and the polymer (C). The acrylic resin composition described above. A laminate comprising a base material and a coating film of a cured product obtained by curing the acrylic resin composition according to claim 1 or 2, which is formed on the surface of the base material.