JP2015052121A - Active energy ray-curable resin composition and coating agent - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an active energy ray-curable resin composition that is excellent in adhesiveness to a metal substrate such as aluminum, and prevents peeling of a coating film or changes in the appearance of a coating film even when a coated metal substrate is folded or boiled.SOLUTION: The active energy ray-curable resin composition comprises: a urethane (meth)acrylate compound (A) obtained by allowing a hydroxyl group-containing (meth)acrylate compound (a1), a polyvalent isocyanate compound (a2) and a polyol compound (a3) to react; a urethane (meth)acrylate compound (B) obtained by allowing a hydroxy group-containing (meth)acrylate compound (b1) and a polyvalent isocyanate compound (b2) to react; an acrylic resin (C); and a phosphate group-containing ethylenically unsaturated compound (D). A content ratio (weight ratio of (A):(B)) of the urethane (meth)acrylate compound (A) to the urethane (meth)acrylate compound (B) ranges from 1:0.1 to 1:2.

Description

  The present invention relates to an active energy ray-curable resin composition, and more particularly to an active energy ray-curable resin composition and a coating agent that form a coating layer having excellent adhesion to a metal such as aluminum.

2. Description of the Related Art Conventionally, active energy ray curable resin compositions have been widely used as coating agents, adhesives, anchor coating agents, and the like on various substrates because curing is completed by irradiation with radiation for a very short time.
However, with regard to the coating agent and paint for forming a cured film on the surface of the metal base material, the coating agent or paint using the active energy ray-curable resin composition is inferior in adhesion to the metal base material. Therefore, it has been difficult to obtain sufficient products, and various developments have been made to improve metal adhesion.
For example, in Patent Document 1, a composition for a coating material containing, as a component of a composition, a phosphate ester having a polymerizable unsaturated group capable of reacting with active energy rays in a molecule is provided on a metal substrate. Have excellent adhesion.
In Patent Document 2, (a) a photocurable acrylate resin, (b) a carboxyl group-containing monofunctional acrylate, (c) phosphoric acid acrylate, (d) a bifunctional acrylate monomer, (e) a trifunctional or higher functional group. A photocurable composition comprising an acrylate monomer and (f) a photoinitiator is excellent in curability, and further, in order to form a uniform film, the cured composition is excellent in adhesion to a steel pipe and surface smoothness. Have been described.

JP 58-219272 A JP 2002-80511 A

  However, in the technologies disclosed in Patent Documents 1 and 2, adhesion to metal substrates is recognized to some extent by using phosphate esters, but the metal substrates are bent during processing and production, or exposed to high temperature conditions. In view of these, it has been demanded to develop an active energy ray-curable resin composition that is excellent in coating performance under more severe conditions and excellent in mechanical properties as a coating agent.

  Therefore, the present invention is excellent in adhesion to a metal base material such as aluminum under such a background, and further, the coating film is peeled off or the appearance is changed even when the coated metal base material is bent or boiled. An object of the present invention is to provide an active energy ray-curable resin composition and a coating agent that do not occur.

However, the present inventors have conducted extensive studies in view of such circumstances, and as a result, active energy ray-curable resin compositions containing urethane (meth) acrylate compounds, acrylic resins, and phosphate group-containing ethylenically unsaturated compounds. In the above, as the urethane (meth) acrylate compound, a urethane (meth) acrylate compound having a structural moiety derived from a polyol component and a urethane (meth) acrylate compound not having a structural moiety derived from a polyol component are used in combination. Thus, the present inventors have found that it is possible to provide an active energy ray-curable resin composition that does not cause peeling of the coating film or change in appearance even when the metal substrate is bent or boiled, thereby completing the present invention. It was.

That is, the gist of the present invention is a urethane (meth) acrylate compound (A) obtained by reacting a hydroxyl group-containing (meth) acrylate compound (a1), a polyvalent isocyanate compound (a2), and a polyol compound (a3). , A hydroxyl group-containing (meth) acrylate compound (b1), a urethane (meth) acrylate compound (B) obtained by reacting a polyvalent isocyanate compound (b2), an acrylic resin (C), and a phosphate group An ethylenically unsaturated compound (D) is contained, and the content ratio (weight ratio) of the urethane (meth) acrylate compound (A) and the urethane (meth) acrylate compound (B) is (A) :( B ) = 1: 0.1 to 1: 2. The present invention relates to an active energy ray-curable resin composition.
Furthermore, in this invention, the coating agent containing the said active energy ray hardening-type resin composition, especially the coating agent for metal substrates are also provided.

  The coating agent using the active energy ray-curable resin composition of the present invention exhibits excellent adhesion to a metal, and further, the coating film is peeled off and the appearance is visible even when the metal substrate after coating is bent or boiled. It has an excellent effect that no change occurs, and also has excellent coating film hardness and scratch resistance.

The present invention is described in detail below.
In the present invention, (meth) acryl means acryl or methacryl, (meth) acryloyl means acryloyl or methacryloyl, and (meth) acrylate means acrylate or methacrylate.

  The urethane (meth) acrylate compound (A) in the present invention is obtained by reacting a hydroxyl group-containing (meth) acrylate compound (a1), a polyvalent isocyanate compound (a2), and a polyol compound (a3). And having a structural site derived from the polyol compound (a3) in the structure.

Examples of the hydroxyl group-containing (meth) acrylate compound (a1) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 4-hydroxybutyl (meth). Acrylate, hydroxyalkyl (meth) acrylate such as 6-hydroxyhexyl (meth) acrylate, 2-hydroxyethylacryloyl phosphate, 2- (meth) acryloyloxyethyl-2-hydroxypropyl phthalate, caprolactone-modified 2-hydroxyethyl (meth) ) Acrylate, dipropylene glycol (meth) acrylate, fatty acid-modified glycidyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) Acrylate, 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, glycerin di (meth) acrylate, 2-hydroxy-3-acryloyl-oxypropyl methacrylate, pentaerythritol tri (meth) acrylate, caprolactone-modified penta Erythritol tri (meth) acrylate, ethylene oxide modified pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, caprolactone modified dipentaerythritol penta (meth) acrylate, ethylene oxide modified dipentaerythritol penta (meth) acrylate, etc. Is mentioned.
Among these, a hydroxyl group (meth) acrylate-based compound having one ethylenically unsaturated group is preferable, and 2-hydroxyethyl (meth) acrylate is particularly preferable in terms of excellent reactivity and versatility.
Moreover, these can be used 1 type or in combination of 2 or more types.

Examples of the polyvalent isocyanate compound (a2) include aromatics such as tolylene diisocyanate, diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, modified diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, phenylene diisocyanate, and naphthalene diisocyanate. Aliphatic polyisocyanates such as polyisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, lysine triisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, norbornene diisocyanate, 1,3-bis (Isocyanatomethyl) Cycloaliphatic polyisocyanates such as hexane, trimer compounds or multimeric compounds of these polyisocyanates, allophanate type polyisocyanates, burette type polyisocyanates, water-dispersed polyisocyanates (for example, manufactured by Nippon Polyurethane Industry Co., Ltd.) "Aquanate 100", "Aquanate 110", "Aquanate 200", "Aquanate 210", etc.).
Among these, cycloaliphatic polyisocyanate compounds are preferably used, and in particular, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, and hydrogenated xylylene diisocyanate have less yellowing of the cured coating film and less curing shrinkage. It is further preferably used in terms of points.

  Examples of the polyol compound (a3) include polyether polyols, polyester polyols, polycarbonate polyols, polyolefin polyols, polybutadiene polyols, (meth) acrylic polyols, polysiloxane polyols, and the like.

  Examples of polyether polyols include polyether polyols containing alkylene structures such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polybutylene glycol, and polyhexamethylene glycol, and random or block copolymers of these polyalkylene glycols. Is mentioned.

Examples of the polyester-based polyol include a condensation polymer of a polyhydric alcohol and a polycarboxylic acid; a ring-opening polymer of a cyclic ester (lactone); a polyhydric alcohol, a polycarboxylic acid, and a cyclic ester. And reactants.
Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, 1,4-tetramethylene diol, 1,3-tetramethylene diol, 2-methyl-1,3-trimethyl. Methylene diol, 1,5-pentamethylene diol, neopentyl glycol, 1,6-hexamethylene diol, 3-methyl-1,5-pentamethylene diol, 2,4-diethyl-1,5-pentamethylene diol, glycerin , Trimethylolpropane, trimethylolethane, cyclohexanediols (such as 1,4-cyclohexanediol), bisphenols (such as bisphenol A), and sugar alcohols (such as xylitol and sorbitol).
Examples of the polyvalent carboxylic acid include aliphatic dicarboxylic acids such as malonic acid, maleic acid, fumaric acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and dodecanedioic acid; -Cycloaliphatic dicarboxylic acids such as cyclohexanedicarboxylic acid; aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, 2,6-naphthalenedicarboxylic acid, paraphenylene dicarboxylic acid, trimellitic acid, and the like.
Examples of the cyclic ester include propiolactone, β-methyl-δ-valerolactone, and ε-caprolactone.

Examples of the polycarbonate-based polyol include a reaction product of a polyhydric alcohol and phosgene; a ring-opening polymerization product of a cyclic carbonate (such as alkylene carbonate).
Examples of the polyhydric alcohol include polyhydric alcohols exemplified in the description of the polyester-based polyol, and examples of the alkylene carbonate include ethylene carbonate, trimethylene carbonate, tetramethylene carbonate, hexamethylene carbonate, and the like. It is done.
In addition, the polycarbonate polyol should just be a compound which has a carbonate bond in a molecule | numerator, and the terminal is a hydroxyl group, and may have an ester bond with a carbonate bond.

  Examples of the polyolefin-based polyol include those having a saturated hydrocarbon skeleton having a homopolymer or copolymer such as ethylene, propylene and butene, and having a hydroxyl group at the molecular end.

Examples of the polybutadiene-based polyol include those having a butadiene copolymer as a hydrocarbon skeleton and having a hydroxyl group at the molecular end.
The polybutadiene-based polyol may be a hydrogenated polybutadiene polyol in which all or part of the ethylenically unsaturated groups contained in the structure thereof are hydrogenated.

  Examples of the (meth) acrylic polyol include those having at least two hydroxyl groups in the molecule of the polymer or copolymer of the (meth) acrylic acid ester. , For example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, (meth) acrylic acid Examples include 2-ethylhexyl, (meth) acrylic acid decyl, (meth) acrylic acid dodecyl, (meth) acrylic acid alkyl esters such as octadecyl (meth) acrylic acid, and the like.

  Examples of the polysiloxane polyol include dimethyl polysiloxane polyol and methylphenyl polysiloxane polyol.

  Among these, polyester-based polyols and polyether-based polyols are preferable, and polyester-based polyols are particularly preferable in terms of excellent mechanical properties such as flexibility during curing.

  As a molecular weight of the polyol type compound (a3) used by this invention, 500-8000 are preferable, Especially preferably, it is 550-5000, More preferably, it is 600-3000. If the molecular weight of the polyol (a3) is too large, mechanical properties such as coating film hardness tend to be reduced during curing, and if it is too small, curing shrinkage tends to be large and stability tends to be lowered.

  The production method of the urethane (meth) acrylate compound (A) is usually the above hydroxyl group-containing (meth) acrylate compound (a1), polyvalent isocyanate compound (a2), polyol compound (a3) in a reactor. The reaction product obtained by reacting the polyol compound (a3) and the polyvalent isocyanate compound (a2) in advance may be added to the hydroxyl group-containing (meth) acrylate compound (a1). ) Is useful in terms of reaction stability and reduction of by-products.

  For the reaction between the polyol compound (a3) and the polyvalent isocyanate compound (a2), known reaction means can be used. At that time, for example, the molar ratio of the isocyanate group in the polyvalent isocyanate compound (a2) to the hydroxyl group in the polyol (a3) is usually about 2n: (2n-2) (n is an integer of 2 or more). Thus, after obtaining a terminal isocyanate group-containing urethane (meth) acrylate compound having an isocyanate group remaining, an addition reaction with the hydroxyl group-containing (meth) acrylate compound (a1) is made possible.

  The addition reaction of the reaction product obtained by reacting the polyol compound (a3) and the polyvalent isocyanate compound (a2) in advance with the hydroxyl group-containing (meth) acrylate compound (a1) is also a known reaction. Means can be used.

The reaction molar ratio between the reaction product and the hydroxyl group-containing (meth) acrylate compound (a1) is, for example, that the polyisocyanate compound (a2) has two isocyanate groups and the hydroxyl group-containing (meth) acrylate compound (a1). ) Has one hydroxyl group, the reaction product: hydroxyl group-containing (meth) acrylate compound (a1) is about 1: 2, and the polyisocyanate compound (a2) has three isocyanate groups. When the hydroxyl group-containing (meth) acrylate compound (a1) has one hydroxyl group, the reaction product: hydroxyl group-containing (meth) acrylate compound (a1) is about 1: 3.
In the addition reaction between the reaction product and the hydroxyl group-containing (meth) acrylate compound (a1), the reaction is terminated when the residual isocyanate group content in the reaction system is 0.5% by weight or less. A (meth) acrylate compound (A) is obtained.

  In the reaction between the polyol (a3) and the polyvalent isocyanate compound (a2), and further in the reaction between the reaction product and the hydroxyl group-containing (meth) acrylate compound (a1), a catalyst is used for the purpose of promoting the reaction. Examples of such catalysts include organic metal compounds such as dibutyltin dilaurate, trimethyltin hydroxide, and tetra-n-butyltin, zinc octoate, tin octoate, cobalt naphthenate, stannous chloride, and chloride. Metal salts such as stannic, triethylamine, benzyldiethylamine, 1,4-diazabicyclo [2,2,2] octane, 1,8-diazabicyclo [5,4,0] undecene, N, N, N ′, N ′ -Amine-based catalysts such as tetramethyl-1,3-butanediamine, N-ethylmorpholine, bismuth nitrate, bismuth bromide, Organic bismuth compounds such as dibutyl bismuth dilaurate, dioctyl bismuth dilaurate, bismuth 2-ethylhexanoate, bismuth naphthenate, bismuth isodecanoate, bismuth neodecanoate, bismuth laurate, etc. Organic acid bismuth salts such as salts, bismuth maleate, bismuth stearate, bismuth oleate, bismuth linoleate, bismuth acetate, bismuth bisneodecanoate, bismuth disalicylate, bismuth digallate, etc. Among them, dibutyltin dilaurate and 1,8-diazabicyclo [5,4,0] undecene are preferable.

  In the reaction of the polyol (a3) with the polyvalent isocyanate compound (a2), and further in the reaction of the reaction product with the hydroxyl group-containing (meth) acrylate compound (a1), a functional group that reacts with an isocyanate group. For example, organic solvents such as esters such as ethyl acetate and butyl acetate, ketones such as methyl ethyl ketone and methyl isobutyl ketone, and aromatic solvents such as toluene and xylene can be used.

  Moreover, reaction temperature is 30-90 degreeC normally, Preferably it is 40-80 degreeC, and reaction time is 2 to 10 hours normally, Preferably it is 3 to 8 hours.

The urethane (meth) acrylate compound (A) used in the present invention preferably has two or more ethylenically unsaturated groups, and preferably has three or more ethylenically unsaturated groups. Is more preferable, and further having 4 or more ethylenically unsaturated groups is further preferable from the viewpoint of the hardness of the cured coating film.
Moreover, the upper limit of the ethylenically unsaturated group which a urethane (meth) acrylate type compound (A) contains is 30 normally, Preferably it is 25 or less.

  The weight average molecular weight of the obtained urethane (meth) acrylate compound (A) is preferably 500 to 50000, and more preferably 1000 to 30000. If the weight average molecular weight is too small, the cured coating film tends to be brittle, and if it is too large, the viscosity tends to be high and difficult to handle.

In addition, said weight average molecular weight is a weight average molecular weight by standard polystyrene molecular weight conversion, a column: Shodex GPC KF-806L (high-performance liquid chromatography (the Showa Denko company make, "Shodex GPC system-11 type | mold")). Exclusion limit molecular weight: 2 × 10 ⁷ , separation range: 100 to 2 × 10 ⁷ , theoretical plate number: 10,000 plate / piece, filler material: styrene-divinylbenzene copolymer, filler particle size: 10 μm) Measured by using this series.

The viscosity of the urethane (meth) acrylate compound (A) at 60 ° C. is preferably 500 to 150,000 mPa · s, particularly 500 to 120,000 mPa · s, more preferably 1,000 to 100,000 mPa · s. It is preferable. When the viscosity is out of the above range, the coatability tends to be lowered.
The viscosity is measured with an E-type viscometer.

  The urethane (meth) acrylate compound (B) in the present invention is obtained by reacting a hydroxyl group-containing (meth) acrylate compound (b1) and a polyvalent isocyanate compound (b2).

Examples of the hydroxyl group-containing (meth) acrylate compound (b1) include those similar to the hydroxyl group-containing (meth) acrylate compound (a1), such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl. Hydroxyalkyl (meth) acrylates such as (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 2-hydroxyethylacryloyl phosphate, 2- ( (Meth) acryloyloxyethyl-2-hydroxypropyl phthalate, caprolactone-modified 2-hydroxyethyl (meth) acrylate, dipropylene glycol (meth) acrylate, fatty acid-modified glycidyl (meth) acrylate, polyester Lenglycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate, glycerin di (meth) acrylate, 2-hydroxy-3-acryloyl-oxy Propyl methacrylate, pentaerythritol tri (meth) acrylate, caprolactone modified pentaerythritol tri (meth) acrylate, ethylene oxide modified pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, caprolactone modified dipentaerythritol penta (meth) Examples thereof include acrylate and ethylene oxide-modified dipentaerythritol penta (meth) acrylate.
Among these, it is preferable to use one or more compounds containing three or more ethylenically unsaturated groups from the viewpoint of the hardness of the cured coating film. Furthermore, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meta) It is particularly preferred to use acrylates).

Examples of the polyvalent isocyanate compound (b2) include those similar to the above polyisocyanate compound (a2), such as tolylene diisocyanate, diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, modified diphenylmethane diisocyanate, xylylene diene. Aromatic polyisocyanates such as isocyanate, tetramethylxylylene diisocyanate, phenylene diisocyanate, naphthalene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate, lysine triisocyanate, hydrogenated diphenylmethane diisocyanate, Hydrogenated xylylene diisocyanate, isophorone diisocyanate, nor Runene diisocyanate, alicyclic polyisocyanate such as 1,3-bis (isocyanatomethyl) cyclohexane, or trimer compound or multimer compound of these polyisocyanates, allophanate type polyisocyanate, burette type polyisocyanate, water dispersion Type polyisocyanate (for example, “Aquanate 100”, “Aquanate 110”, “Aquanate 200”, “Aquanate 210”, etc., manufactured by Nippon Polyurethane Industry Co., Ltd.) and the like.
Among these, cycloaliphatic polyisocyanate compounds are preferably used, and in particular, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, and hydrogenated xylylene diisocyanate have less yellowing of the cured coating film and less cure shrinkage. And more preferably.

The urethane (meth) acrylate compound (B) used in the present invention preferably has 3 or more ethylenically unsaturated groups from the viewpoint of the hardness of the cured coating film, and preferably 4 or more ethylenically unsaturated groups. Particularly preferred are those having a saturated group, more preferred are those having 6 or more ethylenically unsaturated groups, and among them, 6 obtained by reacting pentaerythritol tri (meth) acrylate with isophorone diisocyanate. The urethane (meth) acrylate having an ethylenically unsaturated group is particularly preferred.
Moreover, the upper limit of the ethylenically unsaturated group which a urethane (meth) acrylate type compound (B) contains is 30 normally, Preferably it is 25 or less.

  In order to adjust the number of ethylenically unsaturated groups, the hydroxyl group-containing (meth) acrylate compound (b1) and the polyvalent isocyanate compound (b2) may be appropriately selected and used. When using a hydroxyl group-containing (meth) acrylate compound (b1) having three ethylenically unsaturated groups and using a diisocyanate compound as the polyvalent isocyanate compound (b2), urethane (meth) acrylate The number of ethylenically unsaturated groups in the system compound (B) is six.

  What is necessary is just to manufacture according to the manufacturing method of the said urethane (meth) acrylate type compound (A) about the manufacturing method of a urethane (meth) acrylate type compound (B).

The reaction molar ratio between the polyvalent isocyanate compound (b2) and the hydroxyl group-containing (meth) acrylate compound (b1) is, for example, that the polyisocyanate compound (b2) has two isocyanate groups and has a hydroxyl group content ( When the hydroxyl group of the (meth) acrylate compound (b1) is one, the polyvalent isocyanate compound (b2): hydroxyl group-containing (meth) acrylate compound (b1) is about 1: 2, and the polyisocyanate compound When the compound (b2) has three isocyanate groups and the hydroxyl group-containing (meth) acrylate compound (b1) has one hydroxyl group, the polyvalent isocyanate compound (b2): hydroxyl group-containing (meth) acrylate compound (B1) is about 1: 3.
In the addition reaction between the polyvalent isocyanate compound (b2) and the hydroxyl group-containing (meth) acrylate compound (a1), the reaction is completed when the residual isocyanate group content in the reaction system is 0.5% by weight or less. By making it, a urethane (meth) acrylate type compound (B) is obtained.

  The weight average molecular weight of the obtained urethane (meth) acrylate compound (B) is preferably 500 to 50000, more preferably 1000 to 30000. If the weight average molecular weight is too small, the cured coating film tends to be brittle, and if it is too large, the viscosity tends to be high and difficult to handle.

  The weight average molecular weight is measured in the same manner as described above.

The viscosity of the urethane (meth) acrylate compound (B) at 60 ° C. is preferably 500 to 150,000 mPa · s, particularly 500 to 120,000 mPa · s, more preferably 1,000 to 100,000 mPa · s. It is preferable. When the viscosity is out of the above range, the coatability tends to be lowered.
The viscosity is measured with an E-type viscometer.

As the total amount (sum of (A) and (B)) of the urethane (meth) acrylate compound (A) and the urethane (meth) acrylate compound (B) in the active energy ray-curable resin composition, (A ) To (D) When the total of the components is 100 parts by weight, it is preferably 10 to 80 parts by weight, particularly preferably 20 to 75 parts by weight, and particularly preferably 30 to 70 parts by weight.
If the total amount of the urethane (meth) acrylate compound (A) and the urethane (meth) acrylate compound (B) is too small, the pencil hardness and scratch resistance tend to decrease. Tend to decrease.

Moreover, as a content ratio (weight ratio) of the urethane (meth) acrylate compound (A) and the urethane (meth) acrylate compound (B), (A) :( B) = 1: 0.1 to 1: 2 Particularly preferably, (A) :( B) = 1: 0.2 to 1: 1.8.
If the content ratio of the urethane (meth) acrylate compound (B) is too large, the adhesiveness tends to decrease or the curing shrinkage tends to increase, and if it is too small, the viscosity increases, and the machine has scratch resistance, hardness, etc. The physical properties tend to be reduced.

The acrylic resin (C) in the present invention is obtained by copolymerizing a monomer component containing a (meth) acrylic monomer.
The acrylic resin (C) preferably contains, as a polymerization component, a (meth) acrylic acid ester monomer (c1) as a main component, and if necessary, a functional group-containing monomer (c2) and other copolymers. The polymerizable monomer (c3) can also be used as a copolymerization component.

  Examples of the (meth) acrylic acid ester monomer (c1) include aliphatic (meth) acrylic acid ester monomers such as (meth) acrylic acid alkyl esters and aromatic (meth) acrylic acid phenyl esters ( And (meth) acrylic acid ester monomers.

  About this (meth) acrylic acid alkyl ester, it is preferable that carbon number of an alkyl group is 1-12 normally, especially 1-8, Furthermore, it is preferable that it is 4-8, Specifically, methyl (meth) acrylate , Ethyl (meth) acrylate, n-butyl (meth) acrylate, iso-butyl (meth) acrylate, tert-butyl (meth) acrylate, n-propyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (Meth) acrylate, n-octyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, cetyl (meth) acrylate, stearyl (meth) acrylate, cyclohexyl (meth) acrylate, isobornyl (meth) acrylate, etc. Can be mentioned. Examples of (meth) acrylic acid phenyl ester include benzyl (meth) acrylate and phenoxyethyl (meth) acrylate.

  Other (meth) acrylic acid ester monomers include tetrahydrofurfuryl (meth) acrylate and the like. These can be used alone or in combination of two or more.

  Among these (meth) acrylic acid ester monomers (c1), methyl (meth) acrylate, n-butyl (meth) acrylate, 2 in terms of copolymerizability, adhesive physical properties, ease of handling, and availability of raw materials. -Ethylhexyl (meth) acrylate is preferably used.

  Examples of the functional group-containing monomer (c2) include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an alkoxy group or phenoxy group-containing monomer, an amide group-containing monomer, an amino group-containing monomer, a nitrogen-containing monomer, a glycidyl group-containing monomer, and phosphoric acid. Examples thereof include a group-containing monomer and a sulfonic acid group-containing monomer, which are used alone or in combination of two or more.

  Examples of the hydroxyl group-containing monomer include 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 5-hydroxypentyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl ( (Meth) acrylate, 10-hydroxydecyl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl (meth) acrylate and other (meth) acrylic acid hydroxyalkyl esters, caprolactone-modified 2-hydroxyethyl (meth) acrylate, etc. Monomers containing primary hydroxyl groups such as caprolactone-modified monomers, 2-acryloyloxyethyl-2-hydroxyethylphthalic acid, N-methylol (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, etc. 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 3-chloro-2-hydroxypropyl (meth) acrylate, 2-hydroxy-3 -Secondary hydroxyl group-containing monomers such as phenoxypropyl (meth) acrylate; tertiary hydroxyl group-containing monomers such as 2,2-dimethyl-2-hydroxyethyl (meth) acrylate.

  Further, polyethylene glycol derivatives such as diethylene glycol mono (meth) acrylate and polyethylene glycol mono (meth) acrylate, polypropylene glycol derivatives such as polypropylene glycol mono (meth) acrylate, polyethylene glycol-polypropylene glycol-mono (meth) acrylate, poly (ethylene Oxyalkylene-modified monomers such as glycol-tetramethylene glycol) mono (meth) acrylate and poly (propylene glycol-tetramethylene glycol) mono (meth) acrylate may be used.

  Examples of the carboxyl group-containing monomer include Michael addition of acrylic acid, methacrylic acid, crotonic acid, maleic acid, maleic anhydride, itaconic acid, fumaric acid, acrylamide N-glycolic acid, cinnamic acid, and (meth) acrylic acid. (Eg, acrylic acid dimer, methacrylic acid dimer, acrylic acid trimer, methacrylic acid trimer, acrylic acid tetramer, methacrylic acid tetramer, etc.), 2- (meth) acryloyloxyethyl dicarboxylic acid monoester (eg, 2-acryloyloxyethyl) Succinic acid monoester, 2-methacryloyloxyethyl succinic acid monoester, 2-acryloyloxyethyl phthalic acid monoester, 2-methacryloyloxyethyl phthalic acid monoester, 2-acryloyloxyethyl hexahi Rofutaru acid monoester, 2-methacryloyloxyethyl hexahydrophthalic acid mono ester) and the like. Such a carboxyl group-containing monomer may be used as an acid, or may be used in the form of a salt neutralized with an alkali.

  Examples of the alkoxy group-containing monomer include 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, 2-butoxyethyl (meth) acrylate, and 2-butoxydiethylene glycol. (Meth) acrylate, methoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, octoxypolyethylene glycol Polypropylene glycol-mono (meth) acrylate, lauroxypolyethylene glycol mono (meth) acrylate, stearo Examples include aliphatic (meth) acrylic acid esters such as polyethylene glycol mono (meth) acrylate, and examples of the phenoxy group-containing monomer include 2-phenoxyethyl (meth) acrylate and phenoxypolyethylene glycol (meth) acrylate. And acrylic acid esters of aromatic (meth) acrylates such as phenoxypolyethylene glycol-polypropylene glycol- (meth) acrylate and nonylphenol ethylene oxide adduct (meth) acrylate.

  Examples of the amide group-containing monomer include acrylamide, methacrylamide, N- (n-butoxyalkyl) acrylamide, N- (n-butoxyalkyl) methacrylamide, N, N-dimethyl (meth) acrylamide, N, N- Examples include diethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, acrylamide-3-methylbutylmethylamine, dimethylaminoalkylacrylamide, and dimethylaminoalkylmethacrylamide.

  Examples of the amino group-containing monomer include dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, and a quaternized product thereof.

  Examples of the nitrogen-containing monomer include acryloylmorpholine.

  Examples of the glycidyl group-containing monomer include glycidyl (meth) acrylate and allyl glycidyl ether.

  Examples of the phosphoric acid group-containing monomer include 2- (meth) acryloyloxyethyl acid phosphate, bis (2- (meth) acryloyloxyethyl) acid phosphate, and the like.

Examples of the sulfonic acid group-containing monomer include olefin sulfonic acids such as ethylene sulfonic acid, allyl sulfonic acid, and methallyl sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid, styrene sulfonic acid, and salts thereof. .
These functional group-containing monomers (c2) may be used alone or in combination of two or more.

  Examples of the other copolymerizable monomer (c3) include acrylonitrile, methacrylonitrile, styrene, α-methylstyrene, vinyl acetate, vinyl propionate, vinyl stearate, vinyl chloride, vinylidene chloride, alkyl vinyl ether, vinyl toluene, Examples include vinyl pyridine, vinyl pyrrolidone, itaconic acid dialkyl ester, fumaric acid dialkyl ester, allyl alcohol, acrylic chloride, methyl vinyl ketone, N-acrylamidomethyltrimethylammonium chloride, allyltrimethylammonium chloride, and dimethylallyl vinylketone.

  For the purpose of increasing the molecular weight, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate A compound having two or more ethylenically unsaturated groups such as divinylbenzene can also be used in combination.

  In the acrylic resin (C), the content ratio of the (meth) acrylic acid ester monomer (c1), the functional group-containing monomer (c2), and the other copolymerizable monomer (c3) is (meth) acrylic acid ester monomer (C1) is preferably 10 to 100% by weight, particularly preferably 20 to 95% by weight, and the functional group-containing monomer (c2) is preferably 0 to 90% by weight, particularly preferably 5 to 80% by weight, and other copolymerizable properties. The monomer (c3) is preferably 0 to 50% by weight, particularly preferably 0 to 40% by weight.

  The acrylic resin (C) in the present invention is preferably a polymer having methyl (meth) acrylate as a polymerization component in terms of excellent compatibility with urethane (meth) acrylate, and particularly polymerized methyl metallate. A polymer as a component is preferable, and polymethyl methacrylate is more preferable.

  In the present invention, the acrylic resin (C) is produced by polymerizing the monomer components (c1) to (c3). In the polymerization, solution radical polymerization, suspension polymerization, bulk polymerization, It can be performed by a conventionally known method such as emulsion polymerization. For example, in an organic solvent, a polymerization monomer such as the (meth) acrylic acid ester monomer (c1), a functional group-containing monomer (c2), other copolymerizable monomer (c3), a polymerization initiator (azobisisobutyrate) Ronitrile, azobisisovaleronitrile, benzoyl peroxide, etc.) are mixed or dropped and polymerized at reflux or at 50 to 90 ° C. for 2 to 20 hours.

  The glass transition temperature (Tg) of acrylic resin (C) is 40-120 degreeC normally, Preferably it is 60-110 degreeC. When the glass transition temperature is too high, the thermal shrinkage mitigating action of the cured coating film tends to decrease, and when it is too low, the thermal durability of the cured coating film tends to decrease.

  The weight average molecular weight of the acrylic resin (C) thus obtained is usually 10,000 to 3,000,000, preferably 30,000 to 2.5 million.

  Further, the dispersity (weight average molecular weight / number average molecular weight) of the acrylic resin (A) is preferably 20 or less, particularly preferably 15 or less, and further preferably 10 or less.

In addition, said weight average molecular weight and number average molecular weight are based on standard polystyrene molecular weight conversion, and it is based on high performance liquid chromatography (Nippon Waters, "Waters 2695 (main body)" and "Waters 2414 (detector)"). Column: Shodex GPC KF-806L (exclusion limit molecular weight: 2 × 10 ⁷ , separation range: 100 to 2 × 10 ⁷ , theoretical plate number: 10,000 plates / pack, filler material: styrene-divinylbenzene copolymer, It is measured by using three series of filler particle diameters: 10 μm), and the degree of dispersion is determined from the weight average molecular weight and the number average molecular weight. The glass transition temperature is calculated from the Fox equation.

The content of the acrylic resin (C) is preferably 5 to 120 parts by weight, particularly preferably 10 to 100 parts by weight when the total of the components (A) and (B) is 100 parts by weight. Parts, particularly preferably 20 to 90 parts by weight.
When there is too little content of acrylic resin (C), there exists a tendency for adhesiveness to fall or hardening shrinkage | contraction to become large, and when too large, there exists a tendency for mechanical physical properties, such as scratch resistance, to fall.

Examples of the phosphoric acid group-containing ethylenically unsaturated compound (D) in the present invention include 2- (meth) acryloyloxyethyl phosphate, ethylene (meth) acrylate, trimethylene (meth) acrylate, and phosphoric acid 1 -Phosphoric acid group-containing ethylenically unsaturated compound having one ethylenically unsaturated group such as chloromethylethylene (meth) acrylate, bis (2- (meth) acryloyloxyethyl) phosphate, ethylene oxide-modified phosphoric acid diacrylate And phosphoric acid group-containing ethylenically unsaturated compounds having two or more ethylenically unsaturated groups such as ethylene oxide-modified phosphoric acid di (meth) acrylate and ethylene oxide-modified phosphoric acid tri (meth) acrylate.
Among them, it is preferable to use a compound having two or more ethylenically unsaturated groups from the viewpoint of scratch resistance, and bis (2- (meth) acryloyloxyethyl) phosphate is particularly preferable, and bis (2-methacrylic acid) is particularly preferable. Loyloxyethyl) phosphate is preferred in terms of substrate adhesion.

The content of the phosphoric acid group-containing ethylenically unsaturated compound (D) is preferably 0.05 to 10 parts by weight when the total of the component (A) and the component (B) is 100 parts by weight. The amount is particularly preferably 0.1 to 8 parts by weight, particularly preferably 0.2 to 5 parts by weight.
If the content of the phosphoric acid group-containing ethylenically unsaturated compound (D) is too small, the adhesion tends to decrease. If the content is too large, the substrate is corroded, and mechanical properties such as scratch resistance and hardness are reduced. There is a tendency to decrease.

  In the present invention, in addition to urethane (meth) acrylate compound (A), urethane (meth) acrylate compound (B), acrylic resin (C), and phosphoric acid group-containing ethylenically unsaturated compound (D). It is also preferable to contain a photopolymerization initiator (E) from the viewpoint of exhibiting the effects of the present invention.

  Examples of the photopolymerization initiator (E) include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 4- (2-hydroxyethoxy) phenyl- (2- Hydroxy-2-propyl) ketone, 1-hydroxycyclohexylphenylketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholino) Acetophenones such as phenyl) butanone and 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone oligomer; benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether Benzoin etc. Benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, 2, 4,6-trimethylbenzophenone, 4-benzoyl-N, N-dimethyl-N- [2- (1-oxo-2-propenyloxy) ethyl] benzenemethananium bromide, (4-benzoylbenzyl) trimethylammonium chloride, etc. Benzophenones: 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2- (3-dimethylamino-2-hydroxy)- 3,4- Thioxanthones such as methyl-9H-thioxanthone-9-one mesochloride; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphos Acylphosphine oxides such as fin oxide and bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide; In addition, as for these photoinitiators (E), only 1 type may be used independently and 2 or more types may be used together.

  These auxiliary agents include triethanolamine, triisopropanolamine, 4,4′-dimethylaminobenzophenone (Michler ketone), 4,4′-diethylaminobenzophenone, 2-dimethylaminoethylbenzoic acid, 4-dimethylaminobenzoic acid. Ethyl, 4-dimethylaminobenzoic acid (n-butoxy) ethyl, isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone Etc. can be used in combination.

  Among these, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, benzoyl isopropyl ether, 4- (2-hydroxyethoxy) -phenyl (2-hydroxy-2-propyl) ketone, 2-hydroxy-2-methyl-1- It is preferable to use phenylpropan-1-one.

The content of the photopolymerization initiator (E) is preferably 0.1 to 20 parts by weight, particularly preferably 1 when the total of the components (A) and (B) is 100 parts by weight. -15 parts by weight, particularly preferably 2-10 parts by weight.
If the content of the photopolymerization initiator (E) is too small, curing tends to be poor, and if it is too much, mechanical properties such as scratch resistance and hardness tend to decrease, and embrittlement and coloring problems occur. Tend to occur.

  In the present invention, in addition to the components (A) to (D) and (E), a surface conditioner, a leveling agent, a polymerization inhibitor and the like can be further added as necessary.

The surface conditioner is not particularly limited, and examples thereof include a cellulose-based additive and an alkyd resin.
Such a cellulose-based additive and alkyd resin have an effect of imparting a film-forming property at the time of coating and an effect of increasing the adhesion to a metal vapor deposition surface. The cellulose-based additive is preferably a high-molecular-weight product having a number average molecular weight of 15000 or more in order to reduce fluidity. Examples of such a cellulose-based additive include cellulose-acetate-butyrate resin.

  As the leveling agent, a known general leveling agent can be used as long as it has an effect of imparting wettability to the substrate of the coating liquid and a function of reducing the surface tension. For example, a silicone-modified resin, a fluorine-modified resin An alkyl-modified resin or the like can be used.

  Examples of the polymerization inhibitor include p-benzoquinone, naphthoquinone, tolquinone, 2,5-diphenyl-p-benzoquinone, hydroquinone, 2,5-di-t-butylhydroquinone, methylhydroquinone, hydroquinone monomethyl ether, mono-t- Examples thereof include butyl hydroquinone and pt-butyl catechol.

  The active energy ray-curable resin composition of the present invention includes oil, antioxidant, flame retardant, antistatic agent, filler, stabilizer, reinforcing agent, matting agent, abrasive, inorganic particles (silica Etc.) can also be blended.

  Thus, the active energy containing the urethane (meth) acrylate compound (A), urethane (meth) acrylate compound (B), acrylic resin (C), and phosphoric acid group-containing ethylenically unsaturated compound (D) of the present invention. A linear curable resin composition is obtained.

  Such a resin composition can be used by blending an organic solvent and adjusting the viscosity as necessary. Examples of the organic solvent include alcohols such as methanol, ethanol, propanol, n-butanol and i-butanol, ketones such as acetone, methyl isobutyl ketone, methyl ethyl ketone and cyclohexanone, cellosolves such as ethyl cellosolve, toluene and xylene. Aromatic glycols such as propylene glycol monomethyl ether, acetates such as ethyl acetate and butyl acetate, and diacetone alcohol. These organic solvents may be used alone or in combination of two or more.

  When two or more types are used in combination, a combination of glycol ethers such as propylene glycol monomethyl ether and ketones such as methyl ethyl ketone and alcohols such as methanol, a combination of ketones such as methyl ethyl ketone and alcohols such as methanol, methanol From the viewpoint of the appearance of the coating film, it is preferable to use two or more alcohols such as alcohols in combination.

  The resin composition of the present invention may be applied by diluting usually 10 to 60% by weight, preferably 20 to 40% by weight, using the organic solvent.

In producing the active energy ray-curable resin composition of the present invention, urethane (meth) acrylate compound (A), urethane (meth) acrylate compound (B), acrylic resin (C), phosphate group The mixing method of the containing ethylenically unsaturated compound (D) and the photopolymerization initiator (E) is not particularly limited, and can be mixed by various methods.
Among them, a method in which (A) and (B) are mixed, (C) is added, (D) is added, and (E) is added at the end, and further, organic methods such as ethyl acetate and toluene are used. A method in which a solution in which (A) and (B) are dissolved in a solvent is prepared, (C) dissolved in an organic solvent is added thereto, and (D) and (E) are added thereto in this order. preferable.

  The active energy ray curable resin composition of the present invention is effectively used as a curable resin composition for coating film formation, such as a topcoat agent and an anchor coat agent on various substrates, and is active energy ray curable. After the mold resin composition is applied to the substrate, it is cured by irradiation with active energy rays. The coating method is not particularly limited, and examples thereof include wet coating methods such as spray, shower, dipping, roll, spin, screen printing, and the like.

  As such active energy rays, rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, infrared rays, electromagnetic waves such as X rays and γ rays, electron beams, proton rays, neutron rays, etc. can be used. Curing by ultraviolet irradiation is advantageous from the viewpoint of easy availability and price. In addition, when performing electron beam irradiation, it can harden | cure even without using a photoinitiator (E).

As a method of curing by ultraviolet irradiation, using a high pressure mercury lamp that emits light in a wavelength range of 150 to 450 nm, an ultrahigh pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, a chemical lamp, an electrodeless discharge lamp, an LED, etc. What is necessary is just to irradiate about 30-3000mJ / cm < ² >.
After the ultraviolet irradiation, heating can be performed as necessary to complete the curing.

  As a coating film thickness (film thickness after hardening), it is usually preferable that it is 1-30 micrometers, and it is especially preferable that it is 2-20 micrometers. If the coating film thickness is too thick, the heat shrinkage of the cured coating film tends to increase in a durability test in which a heat load such as a boiling water immersion test is large, and the adhesion to the substrate tends to be reduced. On the other hand, if it is too thin, there is a tendency that the target surface hardness as a UV cured film cannot be obtained.

Such base materials include polyolefin resins, polyester resins, polycarbonate resins, acrylonitrile butadiene styrene copolymers (ABS), polystyrene resins and the like (molds, sheets, cups, etc.), metals, glass Etc.
The active energy ray-curable resin composition of the present invention has excellent adhesion performance to these substrates, but it is particularly difficult to obtain sufficient adhesion with ordinary coating agents. Even when the material is a metal, it has excellent metal adhesion.

  Examples of such a metal include aluminum, copper, iron, SUS, zinc, magnesium, and alloys thereof, and the like, but the effect is particularly remarkable for aluminum, magnesium, and alloys thereof.

  Activity comprising urethane (meth) acrylate compound (A), urethane (meth) acrylate compound (B), acrylic resin (C), phosphoric acid group-containing ethylenically unsaturated compound (D) of the present invention The energy ray curable resin composition is excellent in adhesion to a metal base material such as aluminum, and further excellent in that no peeling of the coating film or appearance change occurs even when the coated metal base material is bent or boiled. This shows the effect. The active energy ray-curable resin composition of the present invention includes paints, pressure-sensitive adhesives, adhesives, adhesives, inks, protective coating agents, anchor coating agents, magnetic powder coating binders, sandblast coatings, plate materials, etc. It is useful as various film forming materials. Among them, it is very useful to use it as a metal-based coating agent.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In the examples, “parts” and “%” mean weight basis unless otherwise specified.

Synthesis example of urethane (meth) acrylate compound (A) [urethane (meth) acrylate compound [A-1]]
In a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas inlet, 37.2 g (0.17 mol) of isophorone diisocyanate, 12.9 g of a trifunctional polyester polyol (hydroxyl value 260 mgKOH / g) ( 0.02 mol), bifunctional polyether polyol (hydroxyl value 175 mgKOH / g) 25.6 g (0.04 mol), 2-hydroxyethyl acrylate 25.8 g (0.22 mol), hydroquinone methyl as a polymerization inhibitor 0.02 g of ether and 0.02 g of dibutyltin dilaurate as a reaction catalyst were charged and reacted at 60 ° C. for 3 hours. When the residual isocyanate group reached 0.3%, the reaction was terminated. -1) was obtained.

[Urethane (meth) acrylate compound [A-2]]
Hydrogenated diphenylmethane diisocyanate 37.2 g (0.17 mol), bifunctional polyether polyol (hydroxyl value 175 mgKOH / g) 51 in a four-necked flask equipped with a thermometer, stirrer, water-cooled condenser and nitrogen gas inlet .3 g (0.08 mol), 2-hydroxyethyl acrylate 19.7 g (0.17 mol), 0.02 g of hydroquinone methyl ether as a polymerization inhibitor, 0.02 g of dibutyltin dilaurate as a reaction catalyst, and 3 at 60 ° C. The reaction was terminated for a period of time, and when the residual isocyanate group became 0.3%, the reaction was terminated to obtain a bifunctional urethane acrylate (A-2).

[Urethane (meth) acrylate compound [A-3]]
In a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas blowing port, 13.7 g (0.06 mol) of isophorone diisocyanate, 101.4 g of a bifunctional polyester polyol (hydroxyl value 45 mg KOH / g) ( 0.04 mol), 2.3 g (0.02 mol) of 2-hydroxyethyl acrylate, 0.02 g of hydroquinone methyl ether as a polymerization inhibitor, and 0.02 g of dibutyltin dilaurate as a reaction catalyst, and reacted at 60 ° C. for 3 hours. When the remaining isocyanate group became 0.3%, the reaction was terminated to obtain a bifunctional urethane acrylate (A-3).

[Urethane (meth) acrylate compound [B-1]]
In a four-necked flask equipped with a thermometer, a stirrer, a water-cooled condenser, and a nitrogen gas blowing port, 19.3 g (0.09 mol) of isophorone diisocyanate, 96.3 g of pentaerythritol triacrylate (hydroxyl value 105 mg KOH / g) .18 mol), 0.02 g of hydroquinone methyl ether as a polymerization inhibitor and 0.02 g of dibutyltin dilaurate as a reaction catalyst were allowed to react at 60 ° C. for 3 hours, and the reaction was performed when the residual isocyanate group reached 0.3%. After completion, hexafunctional urethane acrylate (B-1) was obtained.

[Acrylic resin [C-1]]
To a reactor equipped with a stirrer, a reflux device, a dropping funnel and a nitrogen introduction tube, 50.0 g of toluene (solvent) was added, and the temperature was raised to 80 ° C. while stirring under a nitrogen stream. Next, 50.0 g of methyl methacrylate and a mixture added with an appropriate amount of azobisisobutyronitrile as a polymerization initiator were added dropwise over 2.0 hours, and further maintained at the same temperature for 1.0 hour to complete the polymerization, A solution (concentration 50%) of acrylic resin (C-1) was obtained. The weight average molecular weight (polystyrene conversion) of the obtained (C-1) was 45,000, and the glass transition temperature (Tg) was 100 ° C.

[Acrylic resin [C-2]]
In a reactor equipped with a stirrer, a reflux device, a dropping funnel and a nitrogen introduction tube, 50.0 g of xylene (solvent) was added, and the temperature was raised to 80 ° C. while stirring under a nitrogen stream. Next, a mixture of 32.5 g of methyl methacrylate, 17.5 g of n-butyl methacrylate and an appropriate amount of azobisisobutyronitrile as a polymerization initiator was added dropwise over 2.0 hours and maintained at the same temperature for 1.0 hour. Then, the polymerization was completed to obtain a solution (concentration 50%) of acrylic resin (C-2). The weight average molecular weight (polystyrene conversion) of the obtained (C-2) was 90,000, and the glass transition temperature (Tg) was 75 ° C.

The following were prepared as the phosphoric acid group-containing ethylenically unsaturated compound (D).
[Phosphate group-containing ethylenically unsaturated compound [D-1]]
Bis (2- (meth) acryloyloxyethyl) phosphate (Kyoeisha Chemical Co., Ltd., “Light Ester P-2M”)

The following were prepared as the photopolymerization initiator (E).
[Photopolymerization initiator (E-1)]
1-Hydroxy-cyclohexyl-phenyl-ketone (Ciba Specialty Chemicals, “Irgacure 184”)

Example 1
[Active energy ray-curable resin composition]
Urethane (meth) acrylate compound (A-1), urethane (meth) acrylate compound (B-1), acrylic resin (C-1), phosphoric acid group-containing ethylenically unsaturated compound (D-1) ), A photopolymerization initiator (E-1) is blended at a ratio shown in Table 1 in terms of solid content, diluted with butyl acetate so that the solid content excluding the photopolymerization initiator is 40%, and active energy rays A curable resin composition was obtained.

  The following evaluation was performed about the obtained active energy ray hardening-type resin composition.

<Base material adhesion>
The active energy ray-curable resin composition obtained above was applied to a bar coater No. 1 on an aluminum substrate (JIS H 4000, A1050P). 24, the film thickness after drying was 15 μm, dried at 60 ° C. for 5 minutes, and then from a height of 18 cm to 5.1 m / min using a high pressure mercury lamp 80 W and one lamp. A two-pass ultraviolet irradiation (accumulated irradiation amount: 500 mJ / cm ² ) was performed at a conveyor speed to form a cured coating film. The cured coating film was evaluated by a cross-cut tape method according to JIS K 5400 (1990 edition).

<Bending resistance>
The active energy ray-curable resin composition obtained above was applied to a bar coater No. 1 on an aluminum substrate (JIS H 4000, A1050P). 24, the film thickness after drying was 15 μm, dried at 60 ° C. for 5 minutes, and then from a height of 18 cm to 5.1 m / min using a high pressure mercury lamp 80 W and one lamp. A two-pass ultraviolet irradiation (accumulated irradiation amount: 500 mJ / cm ² ) was performed at a conveyor speed to form a cured coating film. The test piece was allowed to stand for 48 hours in an environment of 23 ° C. and 50% RH, and then tested for bending resistance by a cylindrical mandrel method according to JIS K 5600-5-1: 1999 (mandrel diameter of 2 mm with a type 1 test apparatus, The bending time was 2 seconds and the test was performed in an environment of 23 ° C. and 50%) in the longitudinal direction of the test piece.

<Boiling water resistance>
The active energy ray-curable resin composition obtained above was applied to an aluminum substrate (JIS H 4000, A1050P) with a bar coater NO. 24, the film thickness after drying was 15 μm, dried at 60 ° C. for 5 minutes, and then from a height of 18 cm to 5.1 m / min using a high pressure mercury lamp 80 W and one lamp. A two-pass ultraviolet irradiation (accumulated irradiation amount: 500 mJ / cm ² ) was performed at a conveyor speed to form a cured coating film. The cured coating film formed on the aluminum substrate (JIS H 4000, A1050P) was immersed in boiling water for 1 hour, and the surface state of the coating film was observed. Further, the adhesion to the substrate was evaluated by the cross-cut tape method according to JIS K 5400 (1990 edition) in the same manner as described above. The appearance of the coating film was evaluated according to the following evaluation criteria.
<Appearance of coating film>
○: There was no change.
Δ: The coating film partially whitened.
X: The coating film was whitened.

Example 2
In Example 1, the active energy ray-curable resin was obtained in the same manner as in Example 1 except that the urethane (meth) acrylate compound (A-1) was replaced with the urethane (meth) acrylate compound (A-2). A composition was obtained. Evaluation similar to Example 1 was performed about the obtained active energy ray hardening-type resin composition.

Example 3
In Example 1, the active energy ray-curable resin was obtained in the same manner as in Example 1 except that the urethane (meth) acrylate compound (A-1) was replaced with the urethane (meth) acrylate compound (A-3). A composition was obtained. Evaluation similar to Example 1 was performed about the obtained active energy ray hardening-type resin composition.

Example 4
In Example 1, active energy ray curing was performed in the same manner as in Example 1 except that the blending ratio of the urethane (meth) acrylate compound (A-1) and the urethane (meth) acrylate compound (B-1) was changed. A mold resin composition was obtained. Evaluation similar to Example 1 was performed about the obtained active energy ray hardening-type resin composition.

Example 5
In Example 1, an active energy ray-curable resin composition was obtained in the same manner as in Example 1 except that the acrylic resin (C-1) was changed to the acrylic resin (C-2). Evaluation similar to Example 1 was performed about the obtained active energy ray hardening-type resin composition.

Comparative Example 1
In Example 1, an active energy ray-curable resin composition was obtained in the same manner as in Example 1 except that the urethane (meth) acrylate compound (B-1) was not used. Evaluation similar to Example 1 was performed about the obtained active energy ray hardening-type resin composition.

Comparative Example 2
In Example 1, an active energy ray-curable resin composition was obtained in the same manner as in Example 1 except that the urethane (meth) acrylate compound (A-1) was not used. Evaluation similar to Example 1 was performed about the obtained active energy ray hardening-type resin composition.

  The compositions of the active energy ray-curable resin compositions of Examples and Comparative Examples are shown in [Table 1], and the evaluation results of the cured coating film are shown in [Table 2].

From the above evaluation results, the active energy ray-curable resin containing both the urethane (meth) acrylate compound (A) having a polyol-derived structural moiety and the urethane (meth) acrylate (B) not having a polyol-derived structural moiety. It can be seen that the cured coating films described in Examples 1 to 5 obtained from the compositions are excellent in adhesion to metal and do not cause peeling or change in appearance even when the metal substrate is bent or boiled. .
On the other hand, the cured coating film of Comparative Example 1 obtained from the active energy ray-curable resin composition containing only the urethane (meth) acrylate-based compound (A) having a structural part derived from a polyol is capable of bending metal resistant substrates. Comparative Example 2 obtained from an active energy ray-curable resin composition containing only a urethane (meth) acrylate-based compound (B) having no polyol-derived structural site, resulting in a change in the appearance when boiling, although excellent. Although this cured coating film was excellent in boiling resistance, the result was that the substrate was destroyed when the metal substrate was bent.

  The active energy ray-curable resin composition of the present invention is excellent in coating film hardness and further exhibits an effect of excellent curability, and is a paint, a pressure-sensitive adhesive, an adhesive, an adhesive, an ink, and a protective coating. It is useful as various film forming materials such as a coating agent, an anchor coating agent, a magnetic powder coating binder, a sandblast coating, and a plate material. Among them, it is very useful to use as a coating agent for metal substrates.

Claims (7)

A urethane (meth) acrylate compound (A) obtained by reacting a hydroxyl group-containing (meth) acrylate compound (a1), a polyvalent isocyanate compound (a2), and a polyol compound (a3);
A urethane (meth) acrylate compound (B) obtained by reacting a hydroxyl group-containing (meth) acrylate compound (b1) and a polyvalent isocyanate compound (b2);
Acrylic resin (C), and
Phosphoric acid group-containing ethylenically unsaturated compound (D)
Containing
The content ratio (weight ratio) of the urethane (meth) acrylate compound (A) and the urethane (meth) acrylate compound (B) is (A) :( B) = 1: 0.1 to 1: 2. An active energy ray-curable resin composition.   2. The active energy ray-curable resin composition according to claim 1, wherein the urethane (meth) acrylate compound (B) is a urethane (meth) acrylate compound containing 6 or more ethylenically unsaturated groups. object.   The active energy ray-curable resin composition according to claim 1 or 2, wherein the acrylic resin (C) is a polymer containing methyl methacrylate as a polymerization component.   The active energy ray-curable resin composition according to any one of claims 1 to 3, wherein the phosphoric acid group-containing ethylenically unsaturated compound (D) is a compound having two or more ethylenically unsaturated groups.   The active energy ray-curable resin composition according to claim 1, further comprising a photopolymerization initiator (E).   A coating agent comprising the active energy ray-curable resin composition according to claim 1.   The coating agent according to claim 6, which is used for a coating material for a metal substrate.