JP7040842B2 - Urethane (meth) acrylate, its neutralized product, photocurable resin composition and liquid composition - Google Patents

Description

The present invention relates to urethane (meth) acrylates, neutralized products thereof, photocurable resin compositions and liquid compositions.
This application claims priority based on Japanese Patent Application No. 2019-142965 filed in Japan on August 2, 2019, the contents of which are incorporated herein by reference.

As a photocurable resin, urethane (meth) acrylate having a urethane bond and a (meth) acryloyl group is known. When using urethane (meth) acrylate, the urethane (meth) acrylate is generally diluted with an organic solvent or a reactive diluent. In recent years, it has been studied to dilute urethane (meth) acrylate with water to make it water-based.

The following have been proposed as water-based compositions containing urethane (meth) acrylates.
(1) At least one monomer selected from (meth) acrylates of mono or polypentaerythritol, urethane poly (meth) acrylate compounds having at least two radically polymerizable unsaturated double bonds in one molecule, photo An emulsion coating material composition containing a polymerization initiator, a radical polymerization reactive surfactant, and water (Patent Document 1).
(2) A photocurable resin composition containing a polyfunctional urethane acrylate having a carboxyl group neutralized with an oxyalkylene group and an amino compound, a photopolymerization initiator, and water (Patent Document 2).
(3) A carboxyl group-containing urethane (meth) acrylate was produced in the presence of a water-soluble reactive diluent having a water mixing ratio of 100% by weight or more, and the carboxyl group of the polyurethane (meth) acrylate was used as an amine salt. After that, an aqueous active energy ray-curable resin composition obtained by further adding water and emulsifying (Patent Document 3).
(4) A water-dispersible curable resin composition obtained by dispersing at least one of curable oligomers selected from urethane acrylates and epoxy acrylates in an aqueous solvent in the presence of a reactive emulsifier (Patent Document 4).
(5) The polyfunctional oligomer having 3 to 30 radically polymerizable unsaturated groups is aqueous in the presence of a polyfunctional reactive surfactant which is a urethane (meth) acrylate compound using a polyalkylene glycol derivative. An active energy radical curable emulsion composition dispersed in a solvent and containing an ethylenically unsaturated monomer (Patent Document 5).

Japanese Patent Application Laid-Open No. 9-137081 Japanese Patent Application Laid-Open No. 11-209448 Japanese Patent Application Laid-Open No. 11-279242 Japanese Patent Laid-Open No. 2000-159847 Japanese Patent Application Laid-Open No. 2008-303258

The compositions of Patent Documents 1 to 5 are not aqueous solutions but aqueous dispersions, and their homogeneity is not sufficient.

An object of the present invention is to provide a urethane (meth) acrylate which exhibits water solubility when neutralized and a neutralized product thereof.
Another object of the present invention is to provide a photocurable resin composition containing a water-soluble urethane (meth) acrylate and which can be made into an aqueous solution, and a liquid composition using the same.

The present invention has the following aspects.
[1] It is composed of an amino alcohol component (A) having one hydroxyl group and one or more tertiary amino groups, a diisocyanate compound (B1) and a polyisocyanate compound (B2) having three or more isocyanate groups. It is a reaction product of at least one isocyanate component (B) selected from the group and a (meth) acrylate component (C) having one or more hydroxyl groups.
The isocyanate component (B) contains the polyisocyanate compound (B2), and the (meth) acrylate component (C) is a dipentaerythritol poly (meth) acrylate (C1) having one or more hydroxyl groups and one. It contains at least one selected from the group consisting of pentaerythritol poly (meth) acrylate (C2) having the above hydroxyl groups.
Urethane (meth) acrylate having a weight average molecular weight of 1000 or more.
[2] The amino alcohol component (A) is at least one selected from the group consisting of 2- (dimethylamino) ethanol, 2- (diethylamino) ethanol and 2- (dibutylamino) ethanol, said [1]. Urethane (meth) acrylate.
[3] The diisocyanate compound (B1) is at least one selected from the group consisting of an alicyclic diisocyanate compound and an aliphatic diisocyanate compound.
The urethane (meth) acrylate of the above [1] or [2], wherein the polyisocyanate compound (B2) is at least one selected from the group consisting of an alicyclic polyisocyanate compound and an aliphatic polyisocyanate compound.
[4] The urethane (meth) acrylate according to any one of [1] to [3] above, wherein the polyisocyanate compound (B2) is polyhexamethylene diisocyanate.
[5] The urethane (meth) acrylate according to any one of the above [1] to [4], wherein the diisocyanate compound (B1) is hexamethylene diisocyanate.
[6] A neutralized product in which the tertiary amino group based on the amino alcohol component (A) in the urethane (meth) acrylate according to any one of [1] to [5] is neutralized with a carboxylic acid.
[7] A photocurable resin composition containing the neutralized product of the above [6] and a photopolymerization initiator.
[8] The photocurable resin composition according to the above [7], further comprising a monomer having a polymerizable unsaturated bond.
[9] The (meth) acrylate component (C) contains the dipentaerythritol poly (meth) acrylate (C1).
The photocurable resin composition of the above [8], wherein the monomer contains dipentaerythritol hexa (meth) acrylate.
[10] The photocurable resin composition of the above [9], wherein the hydroxyl value of the mixture of the dipentaerythritol poly (meth) acrylate (C1) and the dipentaerythritol hexa (meth) acrylate is 80 mgKOH / g or more. ..
[11] The (meth) acrylate component (C) contains the pentaerythritol poly (meth) acrylate (C2).
The photocurable resin composition according to any one of [8] to [10], wherein the monomer contains pentaerythritol tetra (meth) acrylate.
[12] The photocurable resin composition according to the above [11], wherein the hydroxyl value of the mixture of the pentaerythritol poly (meth) acrylate (C2) and the pentaerythritol tetra (meth) acrylate is 90 mgKOH / g or more.
[13] A liquid composition containing the photocurable resin composition according to any one of [7] to [12] and water.

According to the present invention, it is possible to provide a urethane (meth) acrylate that exhibits water solubility when neutralized and a neutralized product thereof.
Further, according to the present invention, it is possible to provide a photocurable resin composition containing a water-soluble urethane (meth) acrylate and which can be made into an aqueous solution, and a liquid composition using the same.

In the present specification, "(meth) acryloyl group" is a general term for acryloyl group and methacryloyl group.
"(Meta) acrylate" is a general term for acrylate and methacrylate.
"Urethane (meth) acrylate" is a (meth) acrylate having a urethane bond.
A "poly (meth) acrylate" is a (meth) acrylate having two or more (meth) acryloyl groups.
The "weight average molecular weight" (hereinafter, also referred to as "Mw") is a standard polystyrene-equivalent value measured by a gel permeation chromatography (GPC) method.
The "hydroxyl value" is the amount of potassium hydroxide required to acetylate the hydroxyl group in the sample and neutralize the acetic acid used for acetylation, expressed in mg with respect to 1.0 g of the sample. , A measure of the content of hydroxyl groups in the sample. The hydroxyl value is measured using the neutralization titration method specified in JIS K 0070: 1992.
Hereinafter, preferred embodiments of the present invention will be described, but the present invention is not limited to the following embodiments.

[Urethane (meth) acrylate]
The urethane (meth) acrylate according to one embodiment of the present invention (hereinafter, also referred to as “the present urethane (meth) acrylate”) is referred to as an amino alcohol component (A) (hereinafter, also referred to as “(A) component”). , Isocyanate component (B) (hereinafter, also referred to as "(B) component") and (meth) acrylate component (C) having one or more hydroxyl groups (hereinafter, also referred to as "(C) component"). It is a reaction product of.
This reactant is composed of a unit based on (A) component, a unit based on (B) component, and a unit based on (C) component.

<Ingredient (A)>
The component (A) has one hydroxyl group and one or more tertiary amino groups in the molecule.
The number of tertiary amino groups contained in the component (A) is preferably one from the viewpoint of water solubility.
Examples of the component (A) include compounds represented by (R ¹ ) ₂ -N-R ² . Here, R ¹ represents an alkyl group and R ² represents a hydroxyalkyl group. The two ^R1s in the equation may be the same or different.
R ¹ may be linear or branched. The carbon number of R ¹ is preferably 1 to 4 from the viewpoint of water solubility.
R ² may be linear or branched. The carbon number of ^R2 is preferably 1 to 4 from the viewpoint of water solubility.
As the component (A), at least one selected from the group consisting of 2- (dimethylamino) ethanol, 2- (diethylamino) ethanol and 2- (dibutylamino) ethanol is preferable from the viewpoint of water solubility.
As the component (A), one type may be used alone, or two or more types may be used in combination.

<Ingredient (B)>
The component (B) is at least one selected from the group consisting of the diisocyanate compound (B1) and the polyisocyanate compound (B2) having three or more isocyanate groups (-N = C = O).

"Diisocyanate compound (B1)"
The diisocyanate compound (B1) may be any compound having two isocyanate groups in the molecule, and examples thereof include an aliphatic diisocyanate compound, an alicyclic diisocyanate compound, and an aromatic diisocyanate compound.

Examples of the aliphatic diisocyanate compound include hexamethylene diisocyanate, lysine diisocyanate, trimethylhexamethylene diisocyanate, methylene diisocyanate, ethylene diisocyanate, butylene diisocyanate, propylene diisocyanis, octadecilenisisis, 1,4-tetramethylene diisocyanate, 1,6-. Hexamethylene diisocyanate and 1,10-decamethylene diisocyanate can be mentioned.

Examples of the alicyclic diisocyanate compound include 4,4'-methylenebis (cyclohexylisocyanate), methylcyclohexane-2,4 (or 2,6) -diisocyanate, 1,3- (isocyanatemethyl) cyclohexane, isophorone diisocyanate, and dimer. Examples thereof include acid diisocyanate, 1,3-cyclohexylene diisocyanate, and 4,4'-methylene-bis (cyclohexyl isocyanate).

Examples of the aromatic diisocyanate include tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, xylene diisocyanate, dianisidine diisocyanate, phenyl diisocyanate, halogenated phenyl diisocyanate, 1,5-naphthalenedi isocyanate, and polymethylene polyphenylenedi isocyanate. , Naphthalene diisocyanate, 3-phenyl-2-ethylene diisocyanate, cumene-2,4-diisocyanate, 4-methoxy-1,3-phenylenediisocyanate, 4-ethoxy-1,3-phenylenediocyanate, 2,4'-diisocyanate diphenyl ether , 5,6-dimethyl-1,3-phenylenediisocyanate, 4,4'-diisocyanate diphenyl ether, benzidine diisocyanate, 9,10-anthrusene diisocyanate, 4,4'-diisocyanate benzyl, 3,3'-dimethyl-4, Examples thereof include 4'-diisocyanate diphenylmethane, 2,6-dimethyl-4,4'-diisocyanate diphenyl, 3,3'-dimethoxy-4,4'-diisocyanate diphenyl, 1,4-anthrusene diisocyanate and phenylenediisocyanate.
Each of the above diisocyanates may be an allophanate.

As the diisocyanate compound (B1), at least one selected from the group consisting of an alicyclic diisocyanate compound and an aliphatic diisocyanate compound is preferable from the viewpoint of suppressing yellowing.
Among the above, hexamethylene diisocyanate is preferable from the viewpoint of water solubility.
The diisocyanate compound (B1) may be used alone or in combination of two or more.

"Polyisocyanate compound (B2)"
The polyisocyanate compound (B2) may be any compound having three or more isocyanate groups in the molecule, and examples thereof include an aliphatic polyisocyanate compound, an alicyclic polyisocyanate compound, and an aromatic polyisocyanate compound.

Examples of the aliphatic polyisocyanate compound include multimers, biurets and adducts of the aliphatic diisocyanate compounds.
Examples of the alicyclic polyisocyanate compound include multimers, biurets and adducts of alicyclic diisocyanate compounds.
Examples of the aromatic polyisocyanate compound include multimers of aromatic diisocyanate compounds, biuret and adduct compounds, and triphenylmethane triisocyanate.
Specific examples of the aliphatic diisocyanate compound, the alicyclic polyisocyanate compound, and the aromatic polyisocyanate compound are as described above.
Examples of the multimer include a nurate form (isocyanurate).

As the polyisocyanate compound (B2), at least one selected from the group consisting of an alicyclic polyisocyanate compound and an aliphatic polyisocyanate compound is preferable from the viewpoint of suppressing yellowing.
Among the above, polyhexamethylene diisocyanate (a multimer of hexamethylene diisocyanate) is preferable, and hexamethylene diisocyanate nurate (a nurate form of hexamethylene diisocyanate) is particularly preferable, from the viewpoint of water solubility.
The polyisocyanate compound (B2) may be used alone or in combination of two or more.

The component (B) contains at least the polyisocyanate compound (B2) among the diisocyanate compound (B1) and the polyisocyanate compound (B2) from the viewpoint of water solubility of the neutralized product of the present urethane (meth) acrylate.

The ratio of the polyisocyanate compound (B2) to the total mass of the component (B) is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more. The upper limit of the ratio is not particularly limited and may be 100% by mass. When the ratio of the ratio of the polyisocyanate compound (B2) is at least the above lower limit value, the water solubility of the neutralized product of this urethane (meth) acrylate is more excellent.

<Ingredient (C)>
The component (C) includes dipentaerythritol poly (meth) acrylate (C1) having one or more hydroxyl groups (hereinafter, also referred to as “compound (C1)”) and pentaerythritol poly (meth) having one or more hydroxyl groups. ) Includes at least one selected from the group consisting of acrylate (C2) (hereinafter, also referred to as "compound (C2)").

The compound (C1) is a compound in which 2 or more and 5 or less of the 6 hydroxyl groups of dipentaerythritol are substituted with (meth) acryloyloxy groups. Specific examples thereof include dipentaerythritol di (meth) acrylate, dipentaerythritol tri (meth) acrylate, dipentaerythritol tetra (meth) acrylate and dipentaerythritol penta (meth) acrylate. These compounds (C1) may be used alone or in combination of two or more.

The compound (C2) is a compound in which two or more and three or less of the four hydroxyl groups of pentaerythritol are substituted with a (meth) acryloyloxy group. Specific examples thereof include pentaerythritol di (meth) acrylate and pentaerythritol tri (meth) acrylate. These compounds (C2) may be used alone or in combination of two or more.

When the component (C) contains the compound (C1), the component (C) has two or more hydroxyl groups as the compound (C1) from the viewpoint of water solubility of the neutralized product of the urethane (meth) acrylate. That is, it is preferable to contain at least one selected from the group consisting of dipentaerythritol di (meth) acrylate, dipentaerythritol tri (meth) acrylate and dipentaerythritol tetra (meth) acrylate. As the compound (C1), a compound having two or more hydroxyl groups and a dipentaerythritol tetra (meth) acrylate may be used in combination.
When the component (C) contains the compound (C2), the component (C) has two or more hydroxyl groups as the compound (C2) from the viewpoint of water solubility of the neutralized product of the urethane (meth) acrylate. That is, it is preferable to contain pentaerythritol di (meth) acrylate. As the compound (C2), pentaerythritol di (meth) acrylate and pentaerythritol tri (meth) acrylate may be used in combination.
As the number of hydroxyl groups increases, the amount of tertiary amino groups introduced per molecule of this urethane (meth) acrylate increases, and the water solubility of the neutralized product increases.
The component (C) may further contain a (meth) acrylate having one or more hydroxyl groups other than the compound (C1) and the compound (C2). Examples of such (meth) acrylates include dipentaerythritol mono (meth) acrylates, pentaerythritol mono (meth) acrylates, 2-hydroxyethyl (meth) acrylates, 2-hydroxypropyl acrylates, and 4-hydroxybutyl acrylates. ..
The total ratio of the compound (C1) and the compound (C2) to the total mass of the component (C) is preferably 90% by mass or more, more preferably 95% by mass or more, and may be 100% by mass.

This urethane (meth) acrylate is derived from the component (A) and has a tertiary amino group.
The content of the tertiary amino group in the urethane (meth) acrylate is preferably 0.1 to 6% by mass as the ratio of nitrogen atoms in the tertiary amino group to the total mass of the urethane (meth) acrylate. , 0.2 to 3% by mass is more preferable. When the ratio of the nitrogen atom is at least the above lower limit value, the water solubility of the neutralized product of this urethane (meth) acrylate is more excellent. When the proportion of nitrogen atoms is not more than the above upper limit value, it is easy to obtain a cured product having high surface hardness and excellent scratch resistance and hard coat property. The ratio of the nitrogen atom is obtained by calculating the charging ratio.

The present urethane (meth) acrylate is derived from the component (C) and has a (meth) acryloyl group, and therefore has a polymerizable unsaturated bond (carbon-carbon double bond).
The double bond equivalent of the urethane (meth) acrylate is preferably 125 to 250 g / mol, more preferably 130 to 200 g / mol. When the double bond equivalent is at least the above lower limit value, it is easy to obtain a cured product having high surface hardness and excellent scratch resistance and hard coat property. When the double bond equivalent is not more than the above upper limit value, the towability is more excellent.
"Double bond equivalent" is the mass per mole of double bond in a compound.
When the number of moles of the component (C) required for producing 1 g of the present urethane (meth) acrylate is α mol and the number of polymerizable unsaturated bonds contained in one molecule of the component (C) is β, it is double. The binding equivalent is calculated by 1 / (α × β).
When a plurality of compounds having different numbers of polymerizable unsaturated bonds (number of (meth) acryloyl groups) are used in combination as the component (C), β is the number of polymerizable unsaturated bonds of each compound and the number of each compound. It is a weighted average value calculated from the abundance ratio (molar ratio). The abundance ratio of each compound is determined by the charging ratio.

The Mw of this urethane (meth) acrylate is 1000 or more, preferably 1300 or more.
The Mw of this urethane (meth) acrylate is preferably 20000 or less, more preferably 2000 or less.
The Mw of this urethane (meth) acrylate is preferably 1000 or more and 20000 or less, and more preferably 1300 or more and 2000 or less.

<Manufacturing method of urethane (meth) acrylate>
The present urethane (meth) acrylate can be produced by reacting the component (A), the component (B) and the component (C) (urethaneization reaction). When each of these components is reacted, the hydroxyl groups of the components (A) and (C) and the isocyanate groups of the component (B) form a urethane bond to form the present urethane (meth) acrylate.

The reaction temperature of the urethanization reaction is, for example, 50 to 150 ° C., more preferably 60 to 100 ° C.
The reaction time of the urethanization reaction varies depending on the reaction temperature, the presence or absence of a catalyst, and the type, but is, for example, 6 to 48 hours, further 12 to 36 hours.

In the urethanization reaction, the ratio of each component can be appropriately selected in consideration of the number of hydroxyl groups of the component (A) and the component (C), the physical characteristics after synthesis, and the like.
The ratio (NCO / OH) of the number of isocyanate groups of the component (B) to the total number of the hydroxyl groups of the component (A) and the hydroxyl groups of the component (C) is, for example, 0.5 to 2.
The ratio of the component (A) to the total mass of the component (A), the component (B) and the component (C) is preferably 3 to 30% by mass, more preferably 3 to 15% by mass.
The ratio of the component (B) to the total mass of the component (A), the component (B) and the component (C) is preferably 7 to 50% by mass, more preferably 15 to 40% by mass.
The ratio of the component (C) to the total mass of the component (A), the component (B) and the component (C) is preferably 50 to 90% by mass, more preferably 65 to 80% by mass.
The ratio of the component (A) to the total mass of the component (A) and the component (C) is preferably 3 to 40% by mass, more preferably 5 to 20% by mass.

The urethanization reaction is also referred to as dipentaerythritol hexa (meth) acrylate (hereinafter, also referred to as “DPH (M) A”) or / and pentaerythritol tetra (meth) acrylate (hereinafter, also referred to as “PET (M) A”). It can be done in the presence of.).

When the component (C) contains the compound (C1), the urethanization reaction is typically carried out in the presence of DPH (M) A.
Compound (C1) is generally produced by subjecting dipentaerythritol and (meth) acrylic acid to an esterification reaction, and is produced as a mixture with DPH (M) A. This mixture may contain multiple compounds (C1) with different (meth) acryloyl groups.
When the urethanization reaction is carried out using a mixture of the compound (C1) and DPH (M) A, the DPH (M) A having no hydroxyl group remains as it is without reacting with the component (B), and this urethane A mixture of (meth) acrylate and DPH (M) A is obtained. Since DPH (M) A in the mixture remains as it is without reacting even when the urethane (meth) acrylate in the mixture is neutralized, it can be used as a monomer of the photocurable resin composition.

The hydroxyl value of the mixture of compound (C1) and DPH (M) A is preferably 80 mgKOH / g or more. The larger the hydroxyl value of the mixture, the smaller the proportion of DPH (M) A tends to be. DPH (M) A is water-insoluble by itself, but if the hydroxyl value of the mixture of compound (C1) and DPH (M) A is 80 mgKOH / g or more, the mixture can be mixed with the present urethane (meth) acrylate. A mixture of the present urethane (meth) acrylate and DPH (M) A, which is obtained by obtaining a mixture with DPH (M) A and neutralizing the present urethane (meth) acrylate in the mixture, becomes water-soluble. Cheap.
The upper limit of the hydroxyl value of the mixture of the compound (C1) and DPH (M) A is not particularly limited, but is, for example, 130 mgKOH / g.

When the component (C) contains the compound (C2), the urethanization reaction is typically carried out in the presence of PET (M) A.
Compound (C2) is generally produced by subjecting pentaerythritol and (meth) acrylic acid to an esterification reaction, and is produced as a mixture with PET (M) A. This mixture may contain multiple compounds (C2) with different (meth) acryloyl groups.
When the urethanization reaction is carried out using a mixture of the compound (C2) and PET (M) A, PET (M) A having no hydroxyl group remains as it is without reacting with the component (B), and this urethane A mixture of (meth) acrylate and PET (M) A is obtained. Since PET (M) A in the mixture remains as it is without reacting even when the urethane (meth) acrylate in the mixture is neutralized, it can be used as a monomer of the photocurable resin composition.

The hydroxyl value of the mixture of the compound (C2) and PET (M) A is preferably 90 mgKOH / g or more, more preferably 100 mgKOH / g or more. The larger the hydroxyl value of the mixture, the smaller the proportion of PET (M) A tends to be. PET (M) A is water-insoluble by itself, but if the hydroxyl value of the mixture of compound (C2) and PET (M) A is 90 mgKOH / g or more, the mixture can be mixed with the present urethane (meth) acrylate. A mixture of the present urethane (meth) acrylate and PET (M) A, which is obtained by obtaining a mixture with PET (M) A and neutralizing the present urethane (meth) acrylate in the mixture, becomes water-soluble. Cheap.
The upper limit of the hydroxyl value of the mixture of the compound (C2) and PET (M) A is not particularly limited, but is, for example, 290 mgKOH / g.
The hydroxyl value of the mixture of compound (C2) and PET (M) A may be, for example, 90 to 290 mgKOH / g, and further may be 100 to 290 mgKOH / g.

The urethanization reaction is preferably carried out in the presence of a catalyst from the viewpoint of shortening the reaction time. As the catalyst, a known urethanization catalyst can be used, and examples thereof include organic metal compounds such as dibutyltin acetate, dibutyltin dilaurate and dioctyltin dilaurate, and basic compounds such as triethylenediamine and triethylamine.

The amount of the catalyst used can be appropriately adjusted depending on the activity of the catalyst used, but is preferably 0.01 to 0.50% by mass, preferably 0, based on the total mass of the components (A) and (C). 3.03 to 0.30% by mass is more preferable, and 0.05 to 0.25% by mass is further preferable.

The urethanization reaction is preferably carried out in the presence of a thermal polymerization inhibitor from the viewpoint of suppressing the reaction of the (meth) acryloyl group. As the thermal polymerization inhibitor, known thermal polymerization inhibitors can be used, and examples thereof include 2,6-di-tert-butyl-p-cresol and 4-methoxyphenol.

The amount of the thermal polymerization inhibitor used can be appropriately adjusted depending on the activity of the thermal polymerization inhibitor used, but is preferably 0.01 to 1.5% by mass with respect to 100% by mass of the reactive product, and is 0. It is more preferably 0.03 to 1.0% by mass, and even more preferably 0.03 to 0.8% by mass.

In the urethanization reaction, it is preferable that substantially all of the isocyanate groups in the component (B) react with the component (A) or the component (C).
When the infrared absorption spectrum of the reaction product was measured and the absorption of the wavelength 2200 to 2300 cm ^-1 derived from the isocyanate residue was no longer observed, substantially all of the isocyanate groups in the component (B) were the component (A). Alternatively, it can be determined that the reaction has occurred with the component (C).

[Neutralized urethane (meth) acrylate]
In the neutralized product according to the embodiment of the present invention (hereinafter, also referred to as “the present neutralized product”), the tertiary amino group based on the component (A) in the present urethane (meth) acrylate is a carboxylic acid. It is a sum of things. Water solubility is developed by neutralizing the tertiary amino group with a carboxylic acid.

In this neutralized product, all of the tertiary amino groups may be neutralized, or some of them may be neutralized. From the viewpoint of water solubility, the ratio of the tertiary amino group neutralized with the carboxylic acid to 100 mol% of all the tertiary amino groups in the neutralized product is preferably 80 mol% or more, preferably 95 mol. % Or more is more preferable, and it may be 100 mol%. The higher the proportion of tertiary amino groups neutralized with carboxylic acid, the better the water solubility tends to be.
All the tertiary amino groups in the neutralized product are the sum of the tertiary amino groups neutralized with the carboxylic acid and the tertiary amino groups not neutralized with the carboxylic acid.

The carboxylic acid may be any carboxylic acid having a carboxyl group and capable of neutralizing a tertiary amino group, and examples thereof include acetic acid and acrylic acid. These carboxylic acids may be used alone or in combination of two or more. As the carboxylic acid, acetic acid and acrylic acid are preferable from the viewpoint of solubility in water.

The neutralized product can be produced, for example, by contacting the urethane (meth) acrylate with an aqueous carboxylic acid solution.
The temperature at the time of contact is, for example, 20 to 70 ° C. The contact time is, for example, 10 to 60 minutes.
Instead of the present urethane (meth) acrylate, a mixture of the present urethane (meth) acrylate and DPH (M) A or PET (M) A may be used. In this case, a mixture of the neutralized product and DPH (M) A or PET (M) A is obtained.

[Photocurable resin composition]
The photocurable resin composition according to one embodiment of the present invention (hereinafter, also referred to as “the present resin composition”) contains the present neutralized product and a photopolymerization initiator.
The present resin composition preferably further contains a monomer having a polymerizable unsaturated bond. The present resin composition may further contain other components, if necessary.

When the resin composition is irradiated with light, active species (radicals and cations) are generated by intramolecular cleavage and hydrogen transfer of the photopolymerization initiator, and the active species act on the urethane (meth) acrylate and the monomer. Polymerization or cross-linking reaction occurs, and the present resin composition is cured.

<Photopolymerization initiator>
As the photopolymerization initiator, a known photopolymerization initiator can be used, and for example, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether, α-hydroxyacetophenone, diethoxyacetophenone, 2-hydroxy-2- Methyl-1-phenylpropan-1-one, benzyldimethylketal, 1-hydroxycyclohexyl-phenylketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-benzyl-2-dimethyl Amino-1- (4-morpholinophenyl) butanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoylphenylethoxyphosphine oxide, benzophenone, methyl o-benzoylbenzoate, hydroxybenzophenone , 2-Isopropylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 2,4,6-tris (trichloromethyl) -S-triazine, 2-methyl-4,6 Examples thereof include -bis (trichloro) -S-triazine, 2- (4-methoxyphenyl) -4, 6-bis (trichloromethyl) -S-triazine, iron-allene complex, and titanosen compounds. These photopolymerization initiators may be used alone or in combination of two or more.

<Monomer>
The monomer may be a monofunctional monomer having one polymerizable unsaturated bond or a polyfunctional monomer having two or more polymerizable unsaturated bonds. A monofunctional monomer and a polyfunctional monomer may be used in combination.
The monomer may be a water-soluble monomer or a water-insoluble monomer. A water-soluble monomer and a water-insoluble monomer may be used in combination. The "water-soluble monomer" refers to a monomer that is miscible with water to form a uniform solution.

Examples of the monofunctional monomer include hydroxyl group-containing monofunctional (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl acrylate, and 4-hydroxybutyl acrylate, acryloylmorpholine, dimethylacrylamide, and isobornyl acrylate. Can be mentioned.
Examples of the polyfunctional monomer include hydroxyl group-containing polyfunctional (meth) acrylates such as pentaerythritol di or tri (meth) acrylate, dipentaerythritol di, tri, tetra or penta (meth) acrylate, DPH (M) A and PET. Examples thereof include (M) A, tripropylene glycol diacrylate, and trimethylolpropane triacrylate. These monomers may be used alone or in combination of two or more.

The monomer preferably contains a polyfunctional monomer from the viewpoint of forming a cured film having excellent surface hardness. As the polyfunctional monomer, a monomer having three or more polymerizable unsaturated bonds is preferable, and DPH (M) A and PET (M) A are particularly preferable from the viewpoint of hardness.
When the component (C) contains the compound (C1), it is preferable that the monomer contains DPH (M) A.
When the component (C) contains the compound (C2), it is preferable that the monomer contains PET (M) A.

<Other ingredients>
Other ingredients include thermal polymerization inhibitors, UV absorbers, silane coupling agents, plasticizers, flame retardants, antistatic agents, antiaging agents, antibacterial agents, fungicides, antifoaming agents, leveling agents, fillers, etc. Examples thereof include additives such as thickeners, adhesion-imparting agents, thixo-imparting agents, and brightening materials.

<Contents of each component>
The total content of the urethane (meth) acrylate and the monomer is preferably 20 to 70% by mass, more preferably 30 to 60% by mass, based on the total mass of the resin composition.

The ratio of the urethane (meth) acrylate to the total content of the urethane (meth) acrylate and the monomer is preferably 1 to 30% by mass, more preferably 1 to 20% by mass. If the ratio of the urethane (meth) acrylate is equal to or higher than the lower limit, the resin composition is water-soluble even if it contains a water-insoluble monomer (DPH (M) A, PET (M) A, etc.) as the monomer. Is easy to show.

When the component (C) forming the urethane (meth) acrylate in the resin composition contains the compound (C1) and the monomer contains DPH (M) A, the content of DPH (M) A is the compound ( The amount of the mixture of C1) and DPH (M) A having a hydroxyl value of 80 mgKOH / g or more is preferable. The larger the hydroxyl value of the mixture, the smaller the proportion of DPH (M) A tends to be. DPH (M) A is water-insoluble by itself, but if the hydroxyl value of the mixture of compound (C1) and DPH (M) A is 80 mgKOH / g or more, the present resin composition tends to show water solubility. ..
The upper limit of the hydroxyl value of the mixture of the compound (C1) and DPH (M) A is not particularly limited, but is, for example, 130 mgKOH / g.

When the component (C) forming the urethane (meth) acrylate in the resin composition contains the compound (C2) and the monomer contains PET (M) A, the content of PET (M) A is the compound ( The amount of the mixture of C2) and PET (M) A having a hydroxyl value of 90 mgKOH / g or more is preferable, and an amount having a hydroxyl value of 100 mgKOH / g or more is more preferable. The larger the hydroxyl value of the mixture, the smaller the proportion of PET (M) A tends to be. PET (M) A is water-insoluble by itself, but if the hydroxyl value of the mixture of compound (C2) and PET (M) A is 90 mgKOH / g or more, the present resin composition tends to show water solubility. ..
The upper limit of the hydroxyl value of the mixture of the compound (C2) and PET (M) A is not particularly limited, but is, for example, 290 mgKOH / g.
The hydroxyl value of the mixture of compound (C2) and PET (M) A may be, for example, 90 to 290 mgKOH / g, and further may be 100 to 290 mgKOH / g.

The content of the photopolymerization initiator is preferably 0.5 to 7.0% by mass, more preferably 1 to 5% by mass, based on the total mass of the present resin composition. When the content of the photopolymerization initiator is not less than the lower limit value, the photocurability of the present resin composition is more excellent, and when it is not more than the upper limit value, the storage stability of the present resin composition is more excellent.

The present resin composition can be produced by mixing the present urethane (meth) acrylate, a photopolymerization initiator, a monomer and other components, if necessary. The mixing order of each component is not particularly limited. When the monomer contains DPH (M) A, the present resin composition may be produced by using a mixture of the present urethane (meth) acrylate and DPH (M) A. When the monomer contains PET (M) A, the present resin composition may be produced by using a mixture of the present urethane (meth) acrylate and PET (M) A.

The present resin composition can be cured by irradiating with light to obtain a cured product.
Examples of the light include visible light, ultraviolet rays, plasma, infrared rays, ionizing radiation and the like. Among these, ultraviolet rays are preferable from the viewpoint that the irradiation device is widely used.
The light irradiation conditions can be appropriately selected according to the light source used. The integrated light amount when irradiating with ultraviolet rays is, for example, 50 to 1000 mJ / cm ² .

[Liquid composition]
The liquid composition according to one embodiment of the present invention (hereinafter, also referred to as “the present liquid composition”) includes the present resin composition and water. The liquid composition is typically in the form of an aqueous solution.
The content of the present resin composition in the present liquid composition is, for example, 10 to 60% by mass with respect to the total mass of the present liquid composition.

The liquid composition may further contain a non-reactive diluent other than water, if necessary. The non-reactive diluent is a compound that does not have a polymerizable unsaturated bond and is liquid at room temperature. Other non-reactive diluents are preferably those that are compatible with water, and examples thereof include methanol, ethanol, isopropyl alcohol, and propylene glycol monomethyl ether.
Considering the concept of an aqueous system, the content of the other non-reactive diluent in 100% by mass of the present liquid composition is preferably 15% by mass or less, and particularly preferably 0% by mass.

The liquid composition can be used, for example, to form a coating film made of a cured product of the resin composition. The liquid composition is applied to the surface of an arbitrary substrate and dried to form a coating film composed of the resin composition, and the coating film is irradiated with light to be cured to form the resin composition. A coating film (cured coating film) made of a cured product can be obtained.
Examples of the base material include resins, films, sheets, and molded products. Examples of the resin include polyesters such as polyethylene terephthalate (PET), polycarbonate resins, and ABS resins.
As the coating method, a known coating method can be appropriately adopted, and examples thereof include spray coating, spin coating, and gravure coating.
As the drying conditions, it is sufficient that the non-reactive diluent such as water can be removed, and examples thereof include conditions of 60 to 110 ° C. for 0.5 to 10 minutes.
The light irradiation conditions are the same as described above.
The thickness of the coating film (after drying) can be, for example, 1 to 10 μm.

Hereinafter, the present invention will be specifically described with reference to examples.
In the following, "part" means "part by mass" and "%" means "% by mass".
The "dipentaerythritol acrylate mixture" is a mixture of a plurality of dipentaerythritol acrylates having different numbers of acryloyl groups, contains dipentaerythritol polyacrylate and dipentaerythritol hexaacrylate (DPHA) having a hydroxyl group, and has a hydroxyl value of 80 mgKOH. The one of / g was used.
The "pentaerythritol acrylate mixture" is a mixture of a plurality of pentaerythritol acrylates having different numbers of acryloyl groups, contains pentaerythritol polyacrylate and pentaerythritol tetraacrylate (PETA) having a hydroxyl group, and has a hydroxyl value of 100 mgKOH / g. Was used.
The ratio of urethane acrylate to DPHA in the urethane acrylate / DPHA-containing mixture and the ratio of urethane acrylate to PETA in the urethane acrylate / PETA-containing mixture are the area ratios of GPC (gel permeation chromatography), respectively.

[Manufacturing Example 1]
501 parts of dipentaerythritol acrylate mixture, 50 parts of 2- (dimethylamino) ethanol, 0.2 parts of dibutyltin dilaurate, and 2,6-di in a four-necked flask equipped with a thermometer, a cooling tube, and a stirrer. 0.8 part of -tert-butyl-p-cresol and 249 parts of hexamethylene diisocyanate were added, and the mixture was sufficiently stirred, then the temperature was raised to 70 ° C., and the mixture was stirred and heated for about 24 hours to react. After the reaction, it was confirmed that the isocyanate residue was no longer observed by infrared absorption spectroscopy. In this way, a mixture containing urethane acrylate and DPHA (hereinafter, also referred to as “urethane acrylate / DPHA-containing mixture”) was obtained. The ratio of urethane acrylate to DPHA in the urethane acrylate / DPHA-containing mixture was urethane acrylate: DPHA = 37: 63.

[Production Examples 2 to 3, Comparative Production Examples 1 to 4]
A urethane acrylate / DPHA-containing mixture or a mixture containing urethane acrylate and PETA (hereinafter, "urethane acrylate") is the same as in Production Example 1 except that the type and amount of the material to be charged into the 4-neck flask are changed according to the formulation shown in Table 1. -A mixture containing PETA ”) was obtained. However, in Comparative Production Example 2, since the comparative product was used instead of the component (C), the obtained mixture did not contain DPHA and PETA. Table 1 shows the ratio of urethane acrylate to DPHA or PETA in the urethane acrylate / DPHA-containing mixture or the urethane acrylate / PETA-containing mixture of each production example.

[Example 1]
In a flask equipped with a stirrer, 35 parts of the urethane acrylate / DPHA-containing mixture obtained in Production Example 1 and a photopolymerization initiator (2-hydroxy-4'-(2-hydroxyethoxy) -2-methylpropiophenone) , IGM Resins B.V. product name "Omnirad 2959") (hereinafter, simply referred to as "Omnirad 2959"), 1.1 parts, 1.8 parts of 80% acetic acid, and 66 parts of water. It was charged and stirred for about 1 hour to obtain a liquid composition. The liquid composition after stirring was pale yellow and transparent.
The obtained liquid composition was applied to a film-like easy-adhesive PET having a thickness of 100 μm so that the film thickness after drying was 5 μm, and dried at 100 ° C. to form a coating film. Then, the coating film was irradiated with ultraviolet rays so that the integrated light amount was 500 mJ / cm ² , and a cured coating film was obtained.

[Examples 2 to 4]
A liquid composition was obtained in the same manner as in Example 1 except that the type and amount of the material to be charged into the flask were changed according to the formulation shown in Table 2. In Table 2, "ACMO" indicates acryloylmorpholin. All of the liquid compositions after stirring were pale yellow and transparent.
The obtained liquid composition was applied to a film-like easy-adhesive PET having a thickness of 100 μm so that the film thickness after drying was 5 μm, and dried at 100 ° C. to form a coating film. Then, the coating film was irradiated with ultraviolet rays so that the integrated light amount was 500 mJ / cm ² , and a cured coating film was obtained.

[Comparative Examples 1 to 4]
A liquid composition was obtained in the same manner as in Example 1 except that the type and amount of the material to be charged into the flask were changed according to the formulation shown in Table 2. All of the liquid compositions remained phase-separated even after stirring and did not become transparent.

[evaluation]
The liquid composition and the cured coating film of each example were evaluated as follows. The results are shown in Table 2. For Comparative Examples 1 to 4 in which the evaluation of water solubility was B, no evaluation other than water solubility was performed.

<Water solubility>
The water solubility of the photocurable resin composition (the balance obtained by removing water from the liquid composition of each example) was evaluated according to the following criteria.
A: The liquid composition became transparent after stirring for about 1 hour, and then, even if it was left for 7 days, no phenomenon such as separation occurred.
B: The liquid composition was not transparent after stirring for about 1 hour.

<Curable>
The curability of the photocurable resin composition was evaluated according to the following criteria.
A: The coating film was cured by irradiation with ultraviolet rays having an integrated light intensity of 500 mJ / cm ² .
B: The coating film was not cured by irradiation with ultraviolet rays having an integrated light intensity of 500 mJ / cm ² .
Here, it was confirmed that the coating film was cured by the loss of the tactile touch.

<Pencil hardness>
The pencil hardness of the surface of the cured coating film was measured according to JIS K 5600-5-4.

<Leveling property>
The leveling property of the liquid composition was evaluated according to the following criteria.
A: When the liquid composition was applied to the easy-adhesive PET, no repellency or the like was generated, and a cured coating film having a smooth surface was obtained.
B: When the liquid composition was applied to the easy-adhesive PET, cissing and the like occurred, and a cured coating film having a smooth surface could not be obtained.

In Examples 1 to 4 using the urethane acrylate / DPHA-containing mixture or the urethane acrylate / PETA-containing mixture obtained in Production Examples 1 to 3, the photocurable resin composition showed water solubility. Further, the photocurable resin composition was excellent in curability, the surface hardness of the cured coating film, and the leveling property of the liquid composition.
In Comparative Examples 1 to 4 using the urethane acrylate / DPHA-containing mixture or the urethane acrylate / PETA-containing mixture obtained in Comparative Production Examples 1 to 4, the photocurable resin composition did not show water solubility.

The urethane (meth) acrylate of the present invention exhibits water solubility when neutralized and can be made into an aqueous solution. By making it into an aqueous solution, the leveling property is improved as compared with the case of the aqueous dispersion, and the surface smoothness of the coating film and the physical properties of the coating film after curing (surface hardness, etc.) can be expected to be improved.
The urethane (meth) acrylate of the present invention can be used as a hard coat agent, a cross-linking agent and the like.

Claims (13)

Selected from the group consisting of an amino alcohol component (A) having one hydroxyl group and one or more tertiary amino groups, a diisocyanate compound (B1) and a polyisocyanate compound (B2) having three or more isocyanate groups. It is a reaction product of at least one isocyanate component (B) and a (meth) acrylate component (C) having one or more hydroxyl groups.
The amino alcohol component (A) is a compound represented by (R ¹ ) ₂ -N-R ² , R ¹ represents an alkyl group having 1 to 4 carbon atoms, and two R ^1s are the same but different. R2 may represent a hydroxyalkyl group having 1 to 4 carbon atoms ^.
The diisocyanate compound (B1) is at least one selected from the group consisting of an aliphatic diisocyanate compound, an alicyclic diisocyanate compound and an aromatic diisocyanate compound, and the aliphatic diisocyanate compound is hexamethylene diisocyanate, lysine diisocyanate, or trimethyl. From hexamethylene diisocyanate, methylene diisocyanis, ethylene diisocyanate, butylene diisocyanate, propylene diisocyanate, octadecylenized isocyanate, 1,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,10-decamethylene diisocyanate and allophanates thereof. The alicyclic diisocyanate compound is 4,4'-methylene bis (cyclohexamethylene bis (cyclohexamethylene), methylcyclohexane-2,4 (or 2,6) -diisocyanate, 1,3-(. Hexamethylene diisisethylene) cyclohexane, isophoron diisocyanate, dimerate diisocyanate, 1,3-cyclohexamethylene diisocyanate, 4,4'-methylene-bis (cyclohexamethylene diisocyanis) and at least one selected from the group consisting of allophanates thereof. The aromatic diisocyanate compound is tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, xylene diisocyanate, dianisidine diisocyanate, phenyldiisethylene, halogenated phenyldiisocyanate, 1,5-naphthalenedisisocyanis, naphthalenedisocyanis, 3-phenyl. -2-ethylene diisocyanis, cumene-2,4-diisocyanis, 4-methoxy-1,3-phenylenediisocyanate, 4-ethoxy-1,3-phenylenediisocyanis, 2,4'-diisocyanis diphenyl ether, 5,6-dimethyl- 1,3-Hexamethylene diisocyanate, 4,4'-diisamethylene diphenyl ether, benzidine diisocyanate, 9,10-anthrasamethylene diisocyanate, 4,4'-diisocyanisbenzyl, 3,3'-dimethyl-4,4'-diisocyanisdiphenylmethane, 2, , 6-dimethyl-4,4'-diisocyanate diphenyl, 3,3'-dimethoxy-4,4'-diisocyanate diphenyl, 1,4-anshe It is at least one selected from the group consisting of spiral isocyanate, phenylenedi isocyanate and their allophanates.
The polyisocyanate compound (B2) is at least one selected from the group consisting of an aliphatic polyisocyanate compound, an alicyclic polyisocyanate compound and an aromatic polyisocyanate compound, and the aliphatic polyisocyanate compound is the aliphatic polyisocyanate compound. It is at least one selected from the group consisting of a multimer of a diisocyanate compound, a biuret body and an adduct compound, and the alicyclic polyisocyanate compound is a group consisting of a multimer of the alicyclic diisocyanate compound, a biuret body and an adduct compound. The aromatic polyisocyanate compound is at least one selected from the group consisting of a multimer of the aromatic diisocyanate compound, a biuret form and an adduct compound, and a triphenylmethane triisocyanate.
The isocyanate component (B) contains the polyisocyanate compound (B2), and the isocyanate component (B) contains the polyisocyanate compound (B2).
The group consisting of the dipentaerythritol poly (meth) acrylate (C1) having one or more hydroxyl groups and the pentaerythritol poly (meth) acrylate (C2) having one or more hydroxyl groups in the (meth) acrylate component (C). Including at least one selected from
Urethane (meth) acrylate having a weight average molecular weight of 1000 or more. The urethane according to claim 1, wherein the amino alcohol component (A) is at least one selected from the group consisting of 2- (dimethylamino) ethanol, 2- (diethylamino) ethanol and 2- (dibutylamino) ethanol. (Meta) acrylate. The diisocyanate compound (B1) is at least one selected from the group consisting of the alicyclic diisocyanate compound and the aliphatic diisocyanate compound.
The urethane (meth) acrylate according to claim 1 or 2, wherein the polyisocyanate compound (B2) is at least one selected from the group consisting of the alicyclic polyisocyanate compound and the aliphatic polyisocyanate compound. The urethane (meth) acrylate according to claim 1 or 2, wherein the polyisocyanate compound (B2) is a multimer of hexamethylene diisocyanate. The urethane (meth) acrylate according to any one of claims 1 to 4, wherein the diisocyanate compound (B1) is hexamethylene diisocyanate. A neutralized product in which the tertiary amino group based on the amino alcohol component (A) in the urethane (meth) acrylate according to any one of claims 1 to 5 is neutralized with a carboxylic acid. A photocurable resin composition containing the neutralized product according to claim 6 and a photopolymerization initiator. The photocurable resin composition according to claim 7, further comprising a monomer having a polymerizable unsaturated bond. The (meth) acrylate component (C) contains the dipentaerythritol poly (meth) acrylate (C1).
The photocurable resin composition according to claim 8, wherein the monomer contains dipentaerythritol hexa (meth) acrylate. The photocurable resin composition according to claim 9, wherein the hydroxyl value of the mixture of the dipentaerythritol poly (meth) acrylate (C1) and the dipentaerythritol hexa (meth) acrylate is 80 mgKOH / g or more. The (meth) acrylate component (C) contains the pentaerythritol poly (meth) acrylate (C2).
The photocurable resin composition according to any one of claims 8 to 10, wherein the monomer contains pentaerythritol tetra (meth) acrylate. The photocurable resin composition according to claim 11, wherein the hydroxyl value of the mixture of the pentaerythritol poly (meth) acrylate (C2) and the pentaerythritol tetra (meth) acrylate is 90 mgKOH / g or more. A liquid composition containing the photocurable resin composition according to any one of claims 7 to 12 and water.