Curable composition, cured product thereof, and laminate

Abstract

To provide a curable composition which is applicable to a decorative paper or a decorative sheet and can be cured with less thermal energy than before, a cured product thereof, and a laminate including one or more of them.SOLUTION: The curable composition contains a curable component and a photopolymerization initiator. The curable component contains a polyisocyanate component (A) containing at least two isocyanate groups and a polyol component (B) containing at least two hydroxyl groups. At least one component selected from the component (A) and the component (B) further contains at least one (meth)acryloyl group, and / or the curable component further contains a (meth)acrylate component (C) containing at least one (meth)acryloyl group.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a curable composition, a cured product thereof, and a laminate.

Background Art

[0002] Conventionally, resin-impregnated decorative boards (hereinafter referred to as "decorative boards") have been used as surface materials to enhance the design and durability of housing building materials and furniture. A decorative board is obtained by integrating a resin-impregnated decorative paper (hereinafter referred to as "decorative paper") impregnated with melamine, which is a thermosetting resin, with a base material (such as a wood base material or an inorganic base material).

[0003] As a method for manufacturing decorative paper, for example, (1) an impregnating paper such as a porous base paper is immersed in a tank filled with a melamine resin to impregnate the paper with the melamine resin to obtain decorative paper, and then the decorative paper is overlapped on the upper surface of the base material and thermocompression-molded at a low pressure (low-pressure melamine method), and (2) a method of laminating only melamine resin-impregnated decorative paper and phenol resin-impregnated decorative paper and thermocompression-molding at a high pressure (high-pressure melamine method) are known. These melamine decorative boards have high hardness on the upper surface and are excellent in stain resistance, abrasion resistance, heat resistance, and water resistance, and are difficult to be scratched. Therefore, the decorative board obtained by the low-pressure melamine method is used for furniture materials and interior materials, etc., and the decorative board obtained by the high-pressure melamine method is used for the surface materials of furniture and doors, and the surface materials of shelves and counters, etc., because of its thin thickness. From the viewpoint of obtaining a decorative board excellent in surface smoothness and design, a decorative board in which a top coat layer is further provided on the surface of the decorative paper after manufacturing the decorative paper has also been proposed (for example, Patent Documents 1, 2, etc.).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] By the way, in the production of decorative boards, there is a problem that a large amount of thermal energy is consumed in the production process. That is, in order to produce a decorative board by impregnating, drying, and thermocompression bonding (180°C) a petroleum-derived resin such as a melamine resin or a phenol resin as described above, the amount of thermal energy consumed in the production process becomes enormous. Therefore, a curable material that can produce decorative paper and decorative boards with less thermal energy than conventional thermosetting resins is required. In addition, since thermosetting resins such as melamine resins have a high proportion of petroleum-derived components, a curable material that is environmentally friendly with less petroleum-derived components is also required. In response to such problems, for example, Patent Document 3 proposes a manufacturing apparatus for decorative boards that can reduce the power consumption in the manufacturing process.

[0006] An object of the present disclosure is to provide a curable composition applicable to decorative paper and decorative boards, a curable composition that can be cured with less thermal energy than conventional ones, a cured product thereof, and a laminate containing one or more of these.

Means for Solving the Problems

[0007] As a result of intensive studies by the inventors of the present application, it has been found that the problem can be solved by using a dual-cure material in which the curable component can be used in combination of photocuring (ultraviolet curing, electron beam curing, etc.) and thermosetting, and controlling the ratio of the thermosetting functional group and the photocuring functional group in the curable component. Furthermore, surprisingly, it has been found that this curable material can be cured at a lower temperature than conventional ones, and can also be applied to all of the impregnating resin, top coat layer, and adhesive layer between the substrate of the decorative paper or decorative board. In addition, even if a biomass-derived material is selected as the curable component, the above effects can be maintained, so that an environmentally friendly curable material with a low proportion of petroleum-derived components can be obtained.

[0008] That is, the present invention has the following aspects. [1] It contains a curable component and a photoinitiator, The curable component is a polyisocyanate component (A) containing at least two isocyanate groups, and a polyol component (B) containing at least two hydroxyl groups, and a curable composition, wherein one or more components selected from the component (A) and the component (B) further contain at least one (meth)acryloyl group, and / or further contain a (meth)acrylate component (C) containing at least one (meth)acryloyl group. [2] The curable composition according to [1], wherein one or more components selected from the component (A) and the component (B) further contain at least one (meth)acryloyl group. [3] The curable composition according to [1] or [2], wherein the curable component contains the component (C), and the component (C) contains a hydroxyl group-containing (meth)acrylate (C2) containing at least one (meth)acryloyl group and a hydroxyl group. [4] The curable composition according to any one of [1] to [3], wherein the component (B) contains a (meth)acryloyl group-containing polyol (B2) having at least one (meth)acryloyl group and at least two hydroxyl groups. [5] The curable composition according to any one of [1] to [4], wherein the proportion of the biomass-derived component with respect to the total mass of the curable component is 10% by mass or more. [6] The curable composition according to any one of [1] to [5], wherein the average hydroxyl equivalent of the component (B) is 30 to 5,000. [7] The curable composition according to any one of [1] to [6], wherein the isocyanate index (average isocyanate group equivalent / average hydroxyl group equivalent) of the curable component is 0.01 to 2.0. [8] A cured product of the curable composition according to any one of [1] to [7]. [9] A laminate including one or more layers selected from the curable composition according to any one of [1] to [7] and the cured product according to [8].

[10] The laminate according to [9], which is a resin-impregnated decorative paper or a resin-impregnated decorative board. [Advantages of the Invention]

[0009] According to the present disclosure, it is possible to provide a curable composition that can be cured with less thermal energy than conventional ones, a cured product thereof, and a laminate containing one or more of these.

Brief Description of the Drawings

[0010]

Figure 1

Modes for Carrying Out the Invention

[0011] Hereinafter, an embodiment of the present disclosure will be described in detail. The present disclosure is not limited to the following embodiments, and can be implemented with appropriate modifications within a range that does not inhibit the effects of the present disclosure. Each configuration and their combinations in each embodiment are examples, and within a range not departing from the gist of the present disclosure, additions, omissions, substitutions, and other changes of the configuration are possible as appropriate. The present disclosure is not limited by the embodiments, but is limited only by the scope of the claims. Each aspect disclosed in this specification can be combined with any other features disclosed in this specification. When the specific description given for one embodiment also applies to other embodiments, the description may be omitted in other embodiments. In the present disclosure, the expression "X to Y" for a numerical range means "X or more and Y or less".

[0012] [Curable Composition] The first embodiment in the present disclosure relates to a curable composition containing a curable component and a photopolymerization initiator, wherein the curable component includes a polyisocyanate component (A) containing at least two isocyanate groups and a polyol component (B) containing at least two hydroxyl groups, and one or more components selected from the component (A) and the component (B) further contain at least one (meth)acryloyl group, and / or further contain a (meth)acrylate component (C) containing at least one (meth)acryloyl group. According to the first embodiment, a curable composition that can be cured with less thermal energy than before can be provided.

[0013] <Curable component> The curable composition according to the first embodiment includes a polyisocyanate component (A) containing at least two isocyanate groups and a polyol component (B) containing at least two hydroxyl groups, and one or more components selected from the component (A) and the component (B) further contain at least one (meth)acryloyl group, and / or further contain a (meth)acrylate component (C) containing at least one (meth)acryloyl group, and contains a curable component.

[0014] (Polyisocyanate component (A)) The curable component includes a polyisocyanate component (A) containing at least two isocyanate groups (hereinafter, may also be referred to as "component (A)"). Here, the "polyisocyanate component (A)" contains a polyisocyanate having at least two isocyanate groups (for example, polyisocyanate (A1) and / or (meth)acryloyl group-containing polyisocyanate (A2) described later, etc.) in an amount of 10% by mass or more, preferably 30% by mass or more, more preferably 50% by mass or more based on the total mass of the component (A).

[0015] In one embodiment, the number of isocyanate groups in component (A) (hereinafter referred to as "isocyanate group number (a)") may be 2 to 4, or may be 2 to 3.5. If the isocyanate group number (a) is within the above range, it becomes easier to balance photocuring and thermosetting, and a curable composition that can be cured with less thermal energy can be easily obtained. When component (A) contains polyisocyanate (A1) and (meth)acryloyl group-containing polyisocyanate (A2) described later, the isocyanate group number (a) is the total value of the isocyanate group numbers of polyisocyanate (A1) and (A2).

[0016] The isocyanate group number (a) of component (A) can be calculated from the following formula (1). Isocyanate group number (a) = (number average molecular weight (Mn) of component (A)) × (isocyanate group concentration (mass%) in component (A)) / 4202 ··· (1) In formula (1), the number average molecular weight (Mn) of component (A) can be measured using GPC with solvent: THF, column temperature: 40 °C, and standard substance: polyethylene oxide. Also, the isocyanate group concentration in component (A) can be analyzed by, for example, IR (infrared spectroscopy) or the following titration method etc.

[0017] ·Measurement of isocyanate group concentration The measurement of the isocyanate group concentration (mass%) by the titration method is carried out as follows. The measurement is carried out while stirring with a stirrer using a 100 mL glass flask. First, the blank value is measured as follows. Add 15 mL of a THF solution of dibutylamine (0.1 N) to 15 mL of THF. Further add 3 drops of bromophenol blue (1 mass% methanol diluted solution) to color it blue, and then titrate with an aqueous HCl solution having a normality of 0.1 N. Let the titration volume of the aqueous HCl solution at the point where color change is observed be Vb (mL). Next, measure the actual isocyanate group concentration. First, weigh the sample as Ws (g), dissolve it in 15 mL of THF, and add 15 mL of a THF solution of dibutylamine (0.1 N). After confirming that it has been dissolved, add 3 drops of bromophenol blue (1 mass% methanol dilution) to color it blue, and then titrate with an aqueous HCl solution having a normality of 0.1 N. Let the titration volume of the aqueous HCl solution at the point where color change is observed be Vs (mL). Calculate the isocyanate group concentration in the sample from the following formula (2). Isocyanate group concentration (mass%) = [(Vb - Vs) × 1.005 × 0.42] / Ws ···(2) When using a commercially available product as component (A), the aforementioned isocyanate group concentration and number average molecular weight may adopt the manufacturer's nominal values.

[0018] In one embodiment, the isocyanate group concentration in component (A) may be 5 to 30 mass%, may be 10 to 30 mass%, may be 15 to 30 mass%, or may be 20 to 30 mass%. Further, the number average molecular weight (Mn) of component (A) may be 100 to 1,000, may be 150 to 1,000, may be 150 to 800, or may be 450 to 700. If the number average molecular weight (Mn) and isocyanate group concentration of component (A) are within the above ranges, the curability is likely to be good.

[0019] In one embodiment, the average isocyanate group equivalent of component (A) may be 80 to 1,000 g / moL, may be 90 to 750 g / moL, or may be 100 to 500 g / moL. If the average isocyanate group equivalent of component (A) is within the above range, the curability is likely to be good. Note that the "average isocyanate group equivalent" (hereinafter, may also be referred to as "NCO equivalent") may adopt the value measured in accordance with the standard of JIS K 1603-1, or may adopt the value calculated from the following formula (3). NCO equivalent = (Molecular weight of isocyanate group (NCO group) (42)) / (Isocyanate group concentration (mass%)) × 100 ···(3)

[0020] Component (A) can contain one or more polyisocyanates (A1) selected from polyisocyanate monomers and polyisocyanate derivatives having at least two isocyanate groups.

[0021] (Polyisocyanate (A1)) Examples of the polyisocyanate monomer contained in the polyisocyanate (A1) (hereinafter sometimes referred to as "component (A1)") include polyisocyanates such as aromatic polyisocyanates, araliphatic polyisocyanates, aliphatic polyisocyanates, and alicyclic polyisocyanates.

[0022] ·Aromatic polyisocyanate Examples of the aromatic polyisocyanate include bifunctional aromatic diisocyanates such as tolylene diisocyanate (2,4-, or 2,6-tolylene diisocyanate, or a mixture thereof) (TDI), phenylene diisocyanate (m-, p-phenylene diisocyanate, or a mixture thereof), 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate (NDI), diphenylmethane diisocyanate (4,4'-, 2,4'-, or 2,2'-diphenylmethane diisocyanate, or a mixture thereof) (MDI), 4,4'-toluidine diisocyanate (TODI), and 4,4'-diphenyl ether diisocyanate. Component (A) may contain one of these aromatic polyisocyanates alone or in combination of two or more.

[0023] ·Aryl aliphatic polyisocyanate Examples of the aromatic aliphatic polyisocyanate include bifunctional aromatic aliphatic diisocyanates such as xylylene diisocyanate (1,3- or 1,4-xylylene diisocyanate, or a mixture thereof) (XDI), tetramethylxylylene diisocyanate (1,3- or 1,4-tetramethylxylylene diisocyanate, or a mixture thereof) (TMXDI), ω,ω'-diisocyanate-1,4-diethylbenzene. Component (A) may contain one of these aromatic aliphatic polyisocyanates alone or in combination of two or more thereof.

[0024] ·Aliphatic polyisocyanate Examples of the aliphatic polyisocyanate include bifunctional aliphatic diisocyanates such as trimethylene diisocyanate, 1,2-propylene diisocyanate, butylene diisocyanate (tetramethylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate), 1,5-pentamethylene diisocyanate (PDI), 1,6-hexamethylene diisocyanate (also known as hexamethylene diisocyanate) (HDI), 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanatemethyl caproate. Component (A) may contain one of these aliphatic polyisocyanates alone or in combination of two or more thereof.

[0025] ·Cycloaliphatic polyisocyanate Examples of alicyclic polyisocyanates include, for example, 1,3 - cyclopentane diisocyanate, 1,3 - cyclopentene diisocyanate, cyclohexane diisocyanate (1,4 - cyclohexane diisocyanate, 1,3 - cyclohexane diisocyanate), 3 - isocyanatomethyl - 3,5,5 - trimethylcyclohexyl isocyanate (also known as: isophorone diisocyanate) (IPDI), hydrogenated xylylene diisocyanate (also known as: bis(isocyanatomethyl)cyclohexane) (1,3 - or 1,4 - hydrogenated xylylene diisocyanate, or a mixture thereof) (H6XDI), hydrogenated diphenylmethane diisocyanate (also known as: bis(isocyanatocyclohexyl)methane, methylene bis(cyclohexyl isocyanate)) (trans - trans form, trans - cis form, cis - cis form of 4,4’ -, 2,4’ -, or 2,2’ - methylene bis(cyclohexyl isocyanate), or a mixture thereof) (H 12 MDI), methylcyclohexane diisocyanate (methyl - 2,4 - cyclohexane diisocyanate, methyl - 2,6 - cyclohexane diisocyanate), norbornane diisocyanate (various isomers, or a mixture thereof) (NBDI), and other bifunctional alicyclic diisocyanates. Component (A) may contain one of these alicyclic polyisocyanates alone or in combination of two or more.

[0026] In one embodiment, component (A1) may contain one of the aforementioned polyisocyanate monomers alone or in combination of two or more.

[0027] ·Polyisocyanate derivative Examples of the polyisocyanate derivative include multimers of the aforementioned polyisocyanate monomers (e.g., dimers, trimers (e.g., isocyanurate-modified products, iminooxadiazinedione-modified products), pentamers, heptamers, etc.), allophanate-modified products (e.g., allophanate-modified products produced by the reaction of the aforementioned polyisocyanate monomers with known monohydric alcohols and / or known dihydric alcohols), polyol-modified products (e.g., polyol-modified products (alcohol adducts, etc.) produced by the reaction of the aforementioned polyisocyanate monomers with known alcohols having a valence of 3 or more), biuret-modified products (e.g., biuret-modified products produced by the reaction of the aforementioned polyisocyanate monomers with water or amines), urea-modified products (e.g., urea-modified products produced by the reaction of the aforementioned polyisocyanate monomers with diamines), oxadiazinetrione-modified products (e.g., oxadiazinetriones produced by the reaction of the aforementioned polyisocyanate monomers with carbon dioxide gas), carbodiimide-modified products (e.g., carbodiimide-modified products produced by the decarboxylation condensation reaction of the aforementioned polyisocyanate monomers), uretdione-modified products, uretonimine-modified products, and the like.

[0028] In one embodiment, component (A1) may contain one of the aforementioned polyisocyanate derivatives alone, or two or more thereof may be used in combination. From the viewpoint of easily adjusting the isocyanate functionality (a) to be more than 2, component (A1) preferably contains a polyisocyanate derivative. Further, it may contain multimers of aliphatic diisocyanates.

[0029] When component (A) contains component (A1), it is preferable to use a polyisocyanate having the aforementioned isocyanate group concentration, number average molecular weight (Mn), and NCO equivalent. In a more preferred embodiment, component (A) can contain component (A1) having an isocyanate group concentration of 20 to 30% by mass and an NCO equivalent of 100 to 200 g / mol. Further, the ratio of component (A1) to the total mass of component (A) is preferably 10 to 100% by mass, and more preferably 50 to 100% by mass.

[0030] Component (A) can further contain at least one (meth)acryloyl group. That is, component (A) can contain one or more components selected from component (A1) and (meth)acryloyl group-containing polyisocyanate (A2) which contains at least two isocyanate groups and at least one (meth)acryloyl group. Note that the "(meth)acryloyl group" can include both an acryloyl group and a methacryloyl group.

[0031] ((meth)acryloyl group-containing polyisocyanate (A2)) The number of (meth)acryloyl groups in the (meth)acryloyl group-containing polyisocyanate (A2) (hereinafter sometimes referred to as "component (A2)") may be 1 to 10, may be 2 to 8, or may be 2 to 4. Also, the number of isocyanate groups in component (A2) is 2 or more, and its upper limit is not particularly limited. In one embodiment, component (A2) may be an isocyanate group-containing urethane (meth)acrylate having at least one urethane bond, at least one (meth)acryloyl group, and at least two isocyanate groups in the molecule.

[0032] When component (A) contains component (A2), it is preferable to use a (meth)acryloyl group-containing polyisocyanate having the aforementioned isocyanate group concentration, number average molecular weight (Mn), and NCO equivalent. In a more preferable embodiment, component (A) may contain component (A2) having an isocyanate group concentration of 10 to 15% by mass and an NCO equivalent of more than 200 and 350 or less g / mol. The ratio of component (A2) to the total mass of component (A) may be 0 to 90% by mass, or may be 0 to 50% by mass. In one embodiment, the ratio of component (A2) in component (A) may be 100% by mass.

[0033] As the component (A2), commercially available products may be used. For example, products such as "EBECRYL (registered trademark) 4141", "EBECRYL 4250", "EBECRYL 4510" manufactured by Daicel Ornex Co., Ltd. can be adopted. Further, the component (A2) may be used alone or in combination of two or more kinds.

[0034] In one embodiment, from the viewpoint that the thermosetting property of the curable composition is likely to be good, the component (A) preferably contains the component (A1).

[0035] From the viewpoint that an environmentally friendly curable composition is easily obtained, the component (A1) and the component (A2) may contain components derived from biomass.

[0036] Examples of the biomass-derived component (A1) (hereinafter, the biomass-derived component (A1) is referred to as "component (A11)") include polyisocyanates obtained from plant-derived raw materials. In one embodiment, as the component (A11), those having a biomass content of 40% or more are preferable, and those having a biomass content of 50% or more are more preferable. Examples of the component (A11) having such a biomass content include those obtained by converting a plant-derived dicarboxylic acid into an acid amide and reducing it to convert it into a terminal amino group, and further reacting it with phosgene to convert the amino group into an isocyanate group. Preferably, an aliphatic polyisocyanate having 5 to 18 carbon atoms can be used. Specifically, aliphatic diisocyanates obtained from plant-derived raw materials such as 1,5-pentamethylene diisocyanate, 1,6-hexamethylene diisocyanate, 1,7-heptamethylene diisocyanate, lysine diisocyanate, lysine triisocyanate, dimer acid diisocyanate, octamethylene diisocyanate, and decamethylene diisocyanate can be mentioned. These may be used alone or in combination of two or more kinds.

[0037] In one embodiment, component (A11) may be obtained by converting the amino group in the amino acid, which is a plant-derived raw material, into an isocyanate group using the amino acid as a raw material. For example, the aforementioned pentamethylene diisocyanate derived from biomass may be obtained using lysine as a raw material.

[0038] In one embodiment, component (A11) may contain derivatives such as multimers, biuret-modified products, allophanate-modified products, oxadiazinetrione-modified products, and polyol-modified products of aliphatic polyisocyanates obtained from the aforementioned plant-derived raw materials. Among these, it is preferable to contain a multimer of an aliphatic polyisocyanate.

[0039] Examples of the multimer of the aliphatic polyisocyanate obtained from the plant-derived raw material include dimers such as uretdione, uretoimine, and carbodiimide, and trimers or higher such as isocyanurate and iminooxadiazidione. It is more preferable to contain isocyanurate. In a more preferable embodiment, component (A11) can contain 1,5-pentamethylene diisocyanate and / or its derivative (more preferably isocyanurate) obtained from the plant-derived raw material.

[0040] In other preferable embodiments, as component (A11), an aliphatic polyisocyanate and / or its derivative obtained from the aforementioned plant-derived raw material, having a biomass content of 50% or more and having an isocyanate group concentration and an NCO equivalent similar to those of the aforementioned component (A1), may be used. Commercially available products can also be used as such component (A11). For example, products such as "Stabio (registered trademark) D-370N" and "Stabio D-376N" manufactured by Mitsui Chemicals, Inc. can be adopted.

[0041] Component (A) can contain component (A11) in a proportion similar to that of the aforementioned component (A1).

[0042] Component (A2) can also contain a biomass-derived component (A2) (hereinafter, the biomass-derived component (A2) is referred to as "component (A21)"). The biomass content of component (A21) can be at any ratio.

[0043] Component (A) can contain component (A21) at a ratio similar to that of the aforementioned component (A2).

[0044] (Polyol component (B)) The curable component contains a polyol component (B) (hereinafter, may also be referred to as "component (B)") containing at least two hydroxyl groups. Here, the "polyol component (B)" contains a polyol having at least two hydroxyl groups (for example, polyol (B1) and / or (meth)acryloyl group-containing polyol (B2) described later, etc.) at 10% by mass or more, preferably 30% by mass or more, more preferably 50% by mass or more based on the total mass of component (B).

[0045] In one embodiment, the number of hydroxyl groups of component (B) (hereinafter, referred to as "hydroxyl number (b)") may be 2 or more and less than 4 from the viewpoint that the balance between photocuring and thermosetting is more likely to be good. When component (B) contains polyol (B1) and (meth)acryloyl group-containing polyol (B2) described later, the hydroxyl number (b) is the total value of the hydroxyl numbers of polyol (B1) and (B2).

[0046] In one embodiment, the hydroxyl value of component (B) may be 10 to 2,000 KOHmg / g, or may be 100 to 2,000 KOHmg / g. Also, the number average molecular weight (Mn) of component (B) may be 30 to 10,000, may be 50 to 5,000, or may be 90 to 1,600. In another embodiment, the average hydroxyl equivalent weight of component (B) may be 30 to 5,000 g / mol, may be 30 to 1,000 g / mol, or may be 30 to 600 g / mol. If the number average molecular weight, hydroxyl value, and / or average hydroxyl equivalent weight of component (B) are within the above ranges, the curability is likely to be good. In this specification, for the "hydroxyl value", the method described in the JIS standard can be adopted. The number average molecular weight (Mn) of component (B) can be measured using GPC with the solvent: THF, column temperature: 40 °C, and standard substance: standard polystyrene. Also, for the "average hydroxyl equivalent weight" (hereinafter sometimes referred to as "OH equivalent weight"), a value measured in accordance with the JIS standard may be adopted, or a value calculated from the following formula (4) may be adopted. (Molecular weight of KOH (56.1) × 100) / (Hydroxyl value (KOH mg / g)) × 100 ···(4)

[0047] Component (B) can contain a known or commonly used polyol (B1) having at least two hydroxyl groups in the molecule.

[0048] (Polyol (B1)) The polyol (B1) (hereinafter sometimes referred to as "component (B1)") is not particularly limited. For example, ethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, 1,3 - butanediol, 1,4 - butanediol, 1,6 - hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, dipropylene glycol, polyoxy - C2 - 4 alkylene glycol (such as polyethylene glycol, polypropylene glycol, polyoxytetramethylene glycol, etc.), polyester diol, polyether diol, polycarbonate diol, bisphenol A and its alkylene oxide adduct, bisphenol F and its alkylene oxide adduct, hydrogenated bisphenol A and its alkylene oxide adduct, hydrogenated bisphenol F and its alkylene oxide adduct, cyclohexanediol, cyclohexanedimethanol, tricyclodecane dimethanol, isosorbide, xylene glycol and other diols; glycerin, 1,1,1 - tris(hydroxymethyl)propane, D - sorbitol, xylitol, D - mannitol, D - mannite, diglycerin, polyglycerin, trimethylolethane, trimethylolpropane, pentaerythritol, polyether polyol, polyester polyol, polycarbonate polyol, acrylic polyol, epoxy polyol, natural oil polyol, silicone polyol, fluorine polyol, polyolefin polyol and other polyols having at least three hydroxyl groups in the molecule can be mentioned. Further, as the component (B1), a polyoxyalkylene polyol obtained by adding an alkylene oxide using the above - mentioned polyol as an initiator may be used. The component (B1) can be used alone or in combination of two or more thereof.

[0049] When the component (B) contains the component (B1), it is preferable to use a polyol having the above - mentioned hydroxyl value, number average molecular weight (Mn), and OH equivalent. In a more preferred embodiment, component (B) can contain component (B1) having a hydroxyl value of 10 to 2,000 KOH mg / g and an OH equivalent of 30 to 5,000 g / mol. The ratio of component (B1) to the total mass of component (B) is preferably 10 to 100% by mass, more preferably 20 to 100% by mass, and even more preferably 50 to 100% by mass.

[0050] Component (B) can further contain at least one (meth)acryloyl group. That is, component (B) can contain one or more components selected from component (B1) and (meth)acryloyl group-containing polyol (B2) containing at least two hydroxyl groups and at least one (meth)acryloyl group.

[0051] ((Meth)acryloyl group-containing polyol (B2)) The number of (meth)acryloyl groups in (meth)acryloyl group-containing polyol (hereinafter, may also be referred to as "component (B2)") may be 1 to 10, may be 2 to 8, or may be 2 to 4. The number of hydroxyl groups in component (B2) may be 2 to 10, may be 2 to 8, or may be 2 to 4. In one embodiment, component (B2) may be a hydroxyl group-containing urethane (meth)acrylate having at least one urethane bond, at least one (meth)acryloyl group, and at least two hydroxyl groups in the molecule.

[0052] Examples of component (B2) include trimethylolpropane (meth)acrylate, pentaerythritol (meth)acrylate, pentaerythritol di(meth)acrylate, dipentaerythritol (meth)acrylate, dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, ditrimethylolpropane (meth)acrylate, ditrimethylolpropane di(meth)acrylate, etc. These may be used alone or in combination of two or more.

[0053] When component (B) contains component (B2), it is preferable to use the (meth)acryloyl group-containing polyol having the above-mentioned hydroxyl value, number average molecular weight (Mn), and OH equivalent. In a more preferred embodiment, component (B) can contain one or more component (B2) having a hydroxyl value of 150 to 350 KOHmg / g and an OH equivalent of 100 to 600 g / moL. Further, the ratio of component (B2) to the total mass of component (B) can adopt any value in the range of 10 to 100% by mass.

[0054] In one embodiment, from the viewpoint of facilitating the balance between photocuring and thermosetting, component (B) preferably contains component (B2).

[0055] From the viewpoint of easily obtaining an environmentally friendly curable composition, components (B1) and (B2) may contain components derived from biomass.

[0056] Examples of the biomass-derived component (B1) (hereinafter, the biomass-derived component (B1) is referred to as "component (B11)") include polyol compounds obtained from plant-derived raw materials, and those having a biomass degree of 20% or more are preferable, 40% or more are more preferable, and 50% or more are even more preferable. The biomass degree of component (B11) may be 100%. Examples of such polyol compounds include isosorbide, vegetable oil-based polyols, plant-derived glycerin, bioethylene glycol, bio-1,3-propanediol, biobutylene glycol, and the like. These may be used alone or in combination of two or more.

[0057] Examples of vegetable oil-based polyols include castor oil-based polyols, soybean oil-based polyols, palm oil-based polyols, palm kernel oil-based polyols, coconut oil-based polyols, cashew oil-based polyols, olive oil-based polyols, cottonseed oil-based polyols, safflower oil-based polyols, sesame oil-based polyols, sunflower oil-based polyols, linseed oil-based polyols, etc. The number of hydroxyl groups in a molecule of polyols derived from vegetable oils is usually 2 to 3. Examples of castor oil-based polyols include castor oil, reaction products of castor oil and polyols, esterification reaction products of castor oil fatty acids and polyols, etc. Examples of polyols that react with castor oil or castor oil fatty acids include dihydric polyols such as ethylene glycol, diethylene glycol, and propylene glycol, or polyhydric polyols with three or more hydroxyl groups such as glycerin, trimethylolpropane, hexanetriol, and sorbitol. Examples of soybean oil-based polyols include polyols derived from soybean oil, such as reaction products of soybean oil and polyols, esterification reaction products of soybean oil fatty acids and polyols, etc. The same polyols as those in the case of castor oil described above can be used as the polyols that react with soybean oil or soybean oil fatty acids. The same applies to palm oil-based polyols, cashew oil-based polyols, etc., as in the case of soybean oil-based polyols.

[0058] Component (B) can contain component (B11) in a proportion similar to that of the aforementioned component (B1).

[0059] In one embodiment, as the aforementioned component (B2), it can also contain a biomass-derived component (B2) (hereinafter, the biomass-derived component (B2) is referred to as "component (B21)").

[0060] As the component (B21), those with a biomass content of 10% or more are preferred, those with 20% or more are more preferred, and those with 30% or more are even more preferred. In one embodiment, from the viewpoint of obtaining a curable composition excellent in the balance between photocuring and thermosetting, a polyol-modified (meth)acrylate having 2 to 4 hydroxyl groups and 1 to 4 (meth)acryloyl groups is preferred. As such a polyol-modified (meth)acrylate, sorbitol-modified (meth)acrylate (number of hydroxyl groups: 4, number of (meth)acryloyl groups: 2), epoxidized soybean oil-modified (meth)acrylate (number of hydroxyl groups: 3.5, number of (meth)acryloyl groups: 3.5) are particularly preferred. As such a polyol-modified (meth)acrylate, commercially available products may be used. For example, products such as "ARONIX (registered trademark) M-926" manufactured by Toagosei Co., Ltd., and "EBECRYL 5848" manufactured by Daicel Allnex Co., Ltd. can be adopted. As described above, the component (B) also includes a compound that generates a hydroxyl group in the molecule by ring-opening.

[0061] ((Meth)acrylate component (C)) The curable component contained in the curable composition according to this embodiment can include a (meth)acrylate component (C) (hereinafter, may also be referred to as "component (C)") containing at least one (meth)acryloyl group. Here, the "(meth)acrylate component (C)" contains a (meth)acrylate having at least one (meth)acryloyl group (for example, monofunctional or higher (meth)acrylate (C1) and / or hydroxyl group-containing (meth)acrylate (C2) described later, etc.) in an amount of 10% by mass or more, preferably 30% by mass or more, more preferably 50% by mass or more based on the total mass of the component (C).

[0062] The curable composition according to this embodiment contains a curable component containing an isocyanate group, a hydroxyl group, and a (meth)acryloyl group. Among these, the (meth)acryloyl group may be contained in one or more components selected from component (A) and component (B), may be separately blended as component (C), or may be both. Thus, by containing three different functional groups, the curable composition according to this embodiment can be made into a dual-cure material capable of using both photocuring and thermocuring. Furthermore, by arbitrarily adjusting the numbers of the isocyanate group, hydroxyl group, and (meth)acryloyl group in the curable component, the composition after photocuring can be thermally cured at a lower temperature than before.

[0063] In one embodiment, the number of (meth)acryloyl groups in component (C) (hereinafter referred to as “(meth)acryloyl number (c)”) may be 1 to 20, may be 1 to 10, or may be 1 to 6. If the (meth)acryloyl group number (c) is within the above range, it becomes easier to balance photocuring and thermocuring, and the amount of energy during production is likely to decrease. When component (C) contains a monofunctional or higher (meth)acrylate (C1) and a hydroxyl group-containing (meth)acrylate (C2) described later, the (meth)acryloyl number (c) is the total value of the (meth)acryloyl numbers of (meth)acrylate (C1) and (C2).

[0064] Component (C) can contain a monofunctional or higher (meth)acrylate (C1) (hereinafter sometimes referred to as “component (C1)”) containing at least one (meth)acryloyl group in the molecule.

[0065] (Monofunctional or higher (meth)acrylate (C1)) As the monofunctional (meth)acrylate in the component (C1), for example, aliphatic (meth)acrylates such as methyl (meth)acrylate, ethyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, butoxyethyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, stearyl (meth)acrylate, behenyl (meth)acrylate; alicyclic (meth)acrylates such as cyclohexyl (meth)acrylate, cycloheptyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, isobornyl (meth)acrylate, etc. may be mentioned. These may be used alone or in combination of two or more.

[0066] Examples of the bifunctional (meth)acrylate include aliphatic (meth)acrylates such as ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, tetrapropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, glycerin di(meth)acrylate, tricyclodecane dimethanol (meth)acrylate, ethoxylated 2-methyl-1,3-propanediol di(meth)acrylate; alicyclic (meth)acrylates such as cyclohexane dimethanol (meth)acrylate, ethoxylated cyclohexane dimethanol (meth)acrylate, propoxylated cyclohexane dimethanol (meth)acrylate, ethoxylated propoxylated cyclohexane dimethanol (meth)acrylate, tricyclodecane dimethanol (meth)acrylate, ethoxylated tricyclodecane dimethanol (meth)acrylate, propoxylated tricyclodecane dimethanol (meth)acrylate, ethoxylated propoxylated tricyclodecane dimethanol (meth)acrylate, ethoxylated hydrogenated bisphenol A di(meth)acrylate, propoxylated hydrogenated bisphenol A di(meth)acrylate, ethoxylated propoxylated hydrogenated bisphenol A di(meth)acrylate. These may be used alone or in combination of two or more.

[0067] Examples of the (meth)acrylate having three or more functional groups include aliphatic (meth)acrylates such as trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, ethoxylated propoxylated trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, ethoxylated pentaerythritol tri(meth)acrylate, propoxylated pentaerythritol tri(meth)acrylate, ethoxylated propoxylated pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, propoxylated pentaerythritol tetra(meth)acrylate, ethoxylated propoxylated pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate and the like. These may be used alone or in combination of two or more. Among these, from the viewpoint of the strength of the coating film, it is preferable to contain a (meth)acrylate having two or more functional groups, and it may contain a trifunctional (meth)acrylate or a tetrafunctional (meth)acrylate.

[0068] (Hydroxyl group-containing (meth)acrylate (C2)) In one embodiment, component (C) can contain a hydroxyl group-containing (meth)acrylate (C2) (hereinafter, may also be referred to as "component (C2)") containing at least one (meth)acryloyl group and a hydroxyl group. Here, the number of hydroxyl groups contained in component (C2) is more than 0 and less than 2. The (meth)acrylate having two or more hydroxyl groups is contained in the aforementioned component (B2).

[0069] In one embodiment, the number of (meth)acryloyl groups in component (C2) is not particularly limited and may be 1 to 20, may be 1 to 10, or may be 1 to 6.

[0070] Examples of the component (C2) containing one (meth)acryloyl group and one hydroxyl group in the molecule include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; and hydroxy (meth)acrylate compounds such as (poly)alkylene glycol mono (meth)acrylates such as (poly)ethylene glycol mono (meth)acrylate and (poly)propylene glycol mono (meth)acrylate. These may be used alone or in combination of two or more.

[0071] Examples of the component (C2) containing two or more (meth)acryloyl groups and more than 0 and less than 1 hydroxyl group include glycerin-modified (meth)acrylate (number of hydroxyl groups: 0.5, number of (meth)acryloyl groups: 2.5), pentaerythritol triacrylate, and the like. These may be used alone or in combination of two or more.

[0072] In one embodiment, from the viewpoint of improving thermosetting properties, the component (C) preferably contains the component (C2). More preferably, it contains a hydroxyl group-containing (meth)acrylate containing two or more (meth)acryloyl groups and more than 0 and less than 1 hydroxyl group.

[0073] From the viewpoint of easily obtaining an environmentally friendly curable composition, the component (C2) may contain a biomass-derived component (hereinafter, the biomass-derived component (C2) is referred to as "component (C21)"). The component (C21) may contain the aforementioned component (B11) as a raw material. The biomass content of the component (C21) is preferably 10% or more, more preferably 20% or more, and even more preferably 30% or more. Commercially available products may be used as such a component (C21). For example, products such as "Aronix M-920" (plant-derived raw material glycerin-modified (meth)acrylate) manufactured by Toagosei Co., Ltd. can be adopted.

[0074] (Other Components) In one embodiment, the curable component may contain components other than the aforementioned components (A) to (C) (other components). Examples of other components include isocyanate components other than component (A), hydroxyl group components other than component (B), and the like.

[0075] Examples of the isocyanate component other than component (A) include isocyanate monomers and / or isocyanate derivatives having a number of isocyanate groups in the molecule of more than 0 and less than 2; (meth)acryloyl group-containing isocyanates other than component (A2) (the number of isocyanate groups in the molecule is more than 0 and less than 2), and the like. These may be used alone or in combination of two or more.

[0076] Examples of the hydroxyl group component other than component (B) include monohydric alcohols such as methanol and ethanol. These may be used alone or in combination of two or more.

[0077] In one embodiment, the isocyanate index (average isocyanate group equivalent weight / average hydroxyl group equivalent weight) of the curable component is preferably from 0.01 to 2.0, more preferably from 0.1 to 1.5, and even more preferably from 0.2 to 1.2. In a particularly preferred embodiment, the isocyanate index may be 1.0. By setting the isocyanate index within the above range, a curable composition with an excellent balance between photocuring and thermosetting is likely to be obtained. The isocyanate index refers to a value calculated based on all the isocyanate groups and all the hydroxyl groups contained in the curable component. When the curable component contains an isocyanate component other than the aforementioned component (A) and a hydroxyl group-containing component other than component (B) and component (C2), it is preferable to contain these components within a range that satisfies the aforementioned isocyanate index.

[0078] In one embodiment, the proportion of the biomass-derived component relative to the total mass of the curable component is preferably 10% or more, more preferably 20% or more, and even more preferably 30% or more. Further, from the viewpoint of making the curable composition more environmentally considerate, the proportion of the biomass component in the total mass of the curable component may be 100%.

[0079] <Photoinitiator> The curable composition according to the first embodiment further contains a photoinitiator. Examples of the photoinitiator include benzophenone, acetophenone benzyl, benzyldimethyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, dimethoxyacetophenone, dimethoxyphenylacetophenone, diethoxyacetophenone, diphenyldisulfite, methyl orthobenzoylbenzoate, ethyl 4-dimethylaminobenzoate (e.g., product name "KAYACURE (registered trademark) EPA" manufactured by Nippon Kayaku Co., Ltd., etc.), 2,4-diethylthioxanthone (e.g., product name "KAYACURE DETX" manufactured by Nippon Kayaku Co., Ltd., etc.), 2-methyl-1-[4-(methyl)phenyl]-2-morpholinopropanone-1 (e.g., product name "Irgacure (registered trademark) 907" manufactured by Ciba Geigy Ltd., etc.), 1-hydroxycyclohexyl phenyl ketone (e.g., product name "Omn184" manufactured by IGM, etc.), 2-amino-2-benzoyl-1-phenylalkane compounds such as 2-dimethylamino-2-(4-morpholino)benzoyl-1-phenylpropane, aminobenzene derivatives such as tetra(t-butylperoxycarbonyl)benzophenone, benzyl, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 4,4'-bis(diethylamino)benzophenone, imidazole compounds such as 2,2'-bis(2-chlorophenyl)-4,5,4',5'-tetraphenyl-1,2'-biimidazole (e.g., product name "B-CIM" manufactured by Hodogaya Chemical Co., Ltd., etc.), halomethylated triazine compounds such as 2,6-bis(trichloromethyl)-4-(4-methoxynaphthalen-1-yl)-1,3,5-triazine, and halomethyloxadiazole compounds such as 2-trichloromethyl-5-(2-benzofuran-2-yl-ethenyl)-1,3,4-oxadiazole. These may be used alone or in combination of two or more. Further, a photosensitizer may be added as necessary.

[0080] The content of the photoinitiator in the curable composition is preferably 0.5 to 12% by mass, more preferably 0.5 to 10% by mass, and still more preferably 0.5 to 8% by mass, based on the total mass of the curable composition. When the content of the photoinitiator is within the above range, the curable composition according to the present embodiment can be appropriately cured by ultraviolet rays or the like described later.

[0081] (Other additives) The curable composition according to the present embodiment may contain curable components and optional components (other additives) other than the photoinitiator. The other additives are not particularly limited, and any additives that can be blended into the photocurable composition and / or the thermosetting composition can be blended. For example, a radical polymerization initiator other than the photoinitiator, an ultraviolet absorber, a reaction accelerator, a light stabilizer, a surface conditioner, etc. may be blended.

[0082] ·Ultraviolet absorber As the ultraviolet absorber, known or commonly used ones can be used and are not particularly limited. For example, cyanoacrylate-based, dihydroxybenzophenone-based, benzotriazole-based, triazine-based, benzophenone-based ultraviolet absorbers can be mentioned.

[0083] Examples of the cyanoacrylate-based ultraviolet absorber include 2-ethylhexyl-2-cyano-3,3-diphenylacrylate, ethyl-2-cyano-3,3-diphenylacrylate, and the like. Examples of the dihydroxybenzophenone-based ultraviolet absorber include 2-hydroxy-4-methoxybenzophenone, (2,4-dihydroxyphenyl)-phenylmethane, hydroxymethoxybenzophenone sulfonic acid, 2-(2H-benzotriazol-2-yl)-4-methyl, 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl), 2-(5-chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methyl. Examples of benzotriazole-based ultraviolet absorbers include 2-(2H-benzotriazol-2-yl)-p-cresol, 2-(5-chloro-2H-benzotriazol-2-yl)-6-tert-butyl-4-methylphenol, 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol], and the like. Examples of triazine-based ultraviolet absorbers include 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[2-(2-ethylhexanolyloxy)ethoxy]phenol, 2-(4-((2-hydroxy-3-dodecyloxypropyl)oxy)-2-hydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(4-((2-hydroxy-3-tridecyloxypropyl)oxy)-2-hydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2-(4-((2-hydroxy-3-(2’ethyl)hexyl)oxy)-2-hydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine, 2,4-bis(2-hydroxy-4-butyloxyphenyl)-6-(2,4-bisbutyloxyphenyl)-1,3,5-triazine, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-hexyloxy, and the like. Examples of benzophenone-based ultraviolet absorbers include [2-hydroxy-4-(octyloxy)phenyl]phenylmethanone. The ultraviolet absorber may be used alone or in combination of two or more.

[0084] ·Light stabilizer As the light stabilizer, known or commonly used ones can be used and are not particularly limited. For example, 2,2,6,6-tetraalkyl-4-piperidyl esters (such as 2,2,6,6-tetramethyl-4-piperidyl esters), 4-alkoxy-2,2,6,6-tetraalkylpiperidines [for example, 4-(C1-10 alkoxy)-2,2,6,6-piperidine such as 4-methoxy-2,2,6,6-tetramethylpiperidine; 4-(C6-10 aryloxy)-2,2,6,6-piperidine such as 4-phenoxy-2,2,6,6-tetramethylpiperidine; 4-(C6-10 aryl)-(C1-4 alkyl)-2,2,6,6-tetramethylpiperidine such as 4-benzyloxy-2,2,6,6-tetramethylpiperidine, etc.], bis(2,2,6,6-tetraalkyl-4-piperidyloxy)alkanes [for example, bis(2,2,6,6-tetramethyl-4-piperidyloxy)(C2-6 alkane) such as 1,2-bis(2,2,6,6-tetramethyl-4-piperidyloxy)ethane, etc.], tetrakis(1,2,2,6,6-pentamethyl-4-piperidyl)butane-1,2,3,4-tetracarboxylate; bis(1,2,2,6,6-pentamethyl-4-piperidyl)sebacate; the reaction product of tetramethyl 1,2,3,4-butanetetracarboxylate with 1,2,2,6,6-pentamethyl-4-piperidinol and β,β,β’,β’-tetramethyl-2,4,8,10-tetraoxaspiro[5.5]undecane-3,9-diol, etc. are mentioned. In addition, the light stabilizer may be used alone or in combination of two or more kinds.

[0085] ·Reaction accelerator As the reaction accelerator, known or commonly used ones can be used and are not particularly limited. For example, 1,8-diazabicyclo[5.4.0]undecene-7 (DBU) or its salts (e.g., phenol salt, octylate, p-toluenesulfonate, formate, tetraphenylborate salt, etc.); 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) or its salts (e.g., phenol salt, octylate, p-toluenesulfonate, formate, tetraphenylborate salt, etc.); tertiary amines such as benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, N,N-dimethylcyclohexylamine, etc.; imidazoles such as 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, etc.; phosphate esters; phosphines such as triphenylphosphine, tris(dimethoxy)phosphine, etc.; phosphonium compounds such as tetraphenylphosphonium tetra(p-tolyl)borate; organometallic salts such as zinc octylate, tin octylate, zinc stearate, etc.; metal chelates such as aluminum acetylacetone complex, etc. The reaction accelerator may be used alone or in combination of two or more.

[0086] <Method for producing curable composition> The curable composition according to the first embodiment can be produced by mixing the aforementioned curable component, a photopolymerization initiator, and, if necessary, the aforementioned other additives. As the mixing means, known or commonly used means, for example, various mixers such as a dissolver, a homogenizer, etc., a kneader, a roll, a bead mill, a self-revolving and revolving stirring device, etc. can be used. Conditions such as the temperature and rotation speed during mixing are not particularly limited and can be set as appropriate.

[0087] The curable composition according to the first embodiment can be cured with less thermal energy than before by using photopolymerization and thermal curing in combination. Such a curable composition can be suitably used, for example, as an impregnating resin, an adhesive layer composition, and a topcoat layer composition for decorative boards and decorative papers. Of course, the use of the curable composition is not limited to these for decorative boards and decorative papers.

[0088] [Cured product] The second embodiment in the present disclosure is the cured product of the curable composition according to the first embodiment. The curable composition according to the first embodiment can be made into a cured product by the combined use of light irradiation and heating. Note that the cured product according to the second embodiment includes both those obtained by irradiating the aforementioned curable composition with ultraviolet rays or active energy rays described later to promote the curing reaction, and those obtained by thermally curing after photocuring to achieve complete curing. Also, the "semi-cured product" in a state where the curable composition is irradiated with light or heated until it loses fluidity is also included in the cured product of the present embodiment.

[0089] The cured product according to the present embodiment can be obtained as a cured coating film, for example, by applying the curable composition according to the first embodiment to an object such as a substrate and then performing photocuring and / or thermosetting.

[0090] The method of applying the curable composition is not particularly limited, and a conventionally known method can be adopted. For example, coating methods, casting methods, etc. can be mentioned.

[0091] (Photocuring) Photocuring is preferably performed by irradiating active energy rays such as ultraviolet rays or electron beams. As the light source for ultraviolet irradiation, for example, high-pressure mercury lamps, ultra-high-pressure mercury lamps, carbon arc lamps, xenon lamps, metal halide lamps, etc. are used. The irradiation time of ultraviolet rays can be arbitrarily adjusted between several seconds and several tens of seconds depending on the type of light source, the distance between the light source and the coating surface, and other conditions. On the other hand, in the case of electron beam irradiation, for example, it is preferable to use an electron beam having an energy in the range of 50 to 1000 KeV and an irradiation dose of 2 to 5 Mrad. Usually, an irradiation source with a lamp output of about 80 to 300 W / cm is used.

[0092] (Thermosetting) After photo-curing, it is preferably further thermally cured. The temperature during thermal curing is not particularly limited as long as it can cure the curable composition, but from the viewpoint of reducing thermal energy during production, room temperature is preferable, and from the viewpoint of working speed, heating is preferable.

[0093] The thickness of the cured coating film is not particularly limited and can be arbitrarily adjusted according to the application. For example, it may be adjusted in the range of 0.5 to 1,000 μm, preferably 2 to 500 μm.

[0094] The object (coating object) to which the curable composition is applied is not particularly limited. For example, plastic articles such as polyethylene terephthalate (PET), polycarbonate, polymethacrylate, vinyl chloride resin, etc., those obtained by vapor-depositing metal on the plastic surface of the above articles, various articles such as glass, wood, metal plates, paper, etc. may be mentioned. The coating surface may be subjected to a release treatment.

[0095] [Laminate] The third embodiment of the present disclosure is a laminate including one or more layers selected from the curable composition according to the first embodiment and the cured product according to the second embodiment. Such a laminate is not particularly limited, but is preferably decorative paper or a decorative board. Hereinafter, as an aspect of the laminate, details of decorative paper and decorative boards will be described.

[0096] [Decorative paper] When the laminate according to the third embodiment is decorative paper, the decorative paper is obtained by impregnating a porous base paper with the curable composition according to the first embodiment and then curing it. Note that a pattern layer for enhancing the design or a top coat layer for enhancing the smoothness may be provided on the surface of the decorative paper. That is, the decorative paper according to the present embodiment may be a multilayer body having a layer containing the curable composition and / or cured product according to the present embodiment.

[0097] As the porous base paper, a fibrous sheet-like material such as paper with good water absorbency that can be impregnated with the curable composition may be used. For example, tissue paper, titanium paper, high-quality paper, bleached or unbleached kraft paper, etc. can be used. Among these, it is preferable to adopt titanium paper, which is excellent in both printability and resin impregnation suitability.

[0098] <Decorative board> By further attaching the decorative paper obtained above to the base material, a decorative board can be obtained.

[0099] FIG. 1 is a cross-sectional view showing an example of a decorative board 100 including a decorative paper 10 containing a curable composition and / or a cured product according to this embodiment as an impregnating resin, and a base material 20. The decorative paper 10 in the decorative board 100 of FIG. 1 includes a porous base paper 1, a top coat layer 2, and an adhesive layer 3. The porous base paper 1 is impregnated with the curable composition and / or the cured product according to this embodiment. Also, in the decorative paper 10 of FIG. 1, the top coat layer 2 and the adhesive layer 3 are also composed of the curable composition and / or the cured product according to this embodiment. Such a decorative board 100 is obtained, for example, by coating one surface of the base material 20 with the curable composition according to this embodiment by an arbitrary method, then laminating the porous base paper 1, and impregnating the porous base paper 1 with the curable composition. Thereby, the adhesive layer 3 can also be laminated on one surface (the surface on the base material 20 side) of the porous base paper 1. Then, the curable composition according to this embodiment is further coated on the other surface of the porous base paper 1 to laminate the top coat layer 2. After covering the surface of the top coat layer 2 with a resin film (such as a PET film), ultraviolet rays or active energy rays are irradiated from the resin film side to cure the top coat layer 2. Then, the resin film is peeled off and further thermally cured to cure the impregnating resin and the adhesive layer 3. Thereby, the decorative paper 10 and the base material 20 can be integrated to obtain the decorative board 100.

[0100] As the base material 20, a plate-shaped base material is preferable, and for example, an inorganic base material, a wood base material, an organic base material, etc. can be adopted. Examples of the inorganic base material include cement boards, volcanic glass multi-layer boards, calcium silicate boards, magnesium silicate boards, magnesium oxide boards, and the like. Examples of the wood base material include plywood, insulation boards, MDF (Medium Density Fiberboard), hard boards, particle boards, oriented strand boards, and the like. Examples of the organic base material include plastic boards such as thermosetting resins or thermoplastic resins. Specifically, for example, phenolic resin boards, polycarbonate boards, acrylic resin boards, rigid vinyl chloride boards, flexible vinyl chloride boards, polypropylene resin boards, polystyrene resin boards, polyethylene terephthalate (PET) resin boards, and the like can be mentioned. Among these, from the viewpoint of easily obtaining a decorative board with excellent non-combustibility and excellent strength, an inorganic base material is preferable.

[0101] The thickness of the base material 20 is not particularly limited, but from the viewpoints of the strength of the base material and ease of handling, 20 μm to 25 mm is preferable.

[0102] As described above, the decorative paper and the decorative board containing the curable composition according to the present embodiment can cure the impregnated resin by using both photocuring and thermocuring, and thus can be manufactured with less thermal energy than in the past.

Examples

[0103] Hereinafter, the present invention will be described in detail with reference to examples, but the present invention is not limited to the following description.

[0104] [Materials] The materials used in the examples and comparative examples are as follows. The details of each component are described in Table 1. <Component (A)> · Component (A11-1): Biomass-derived 1,5-pentamethylene diisocyanate derivative (manufactured by Mitsui Chemicals, Inc., product name "Stabio D-370N"). · Component (A11-2): Biomass-derived 1,5-pentamethylene diisocyanate derivative (manufactured by Mitsui Chemicals, Inc., product name "Stabio D-376N"). · Component (A2-1): Isocyanate group-containing acrylate (manufactured by Daicel Ornex Co., Ltd., product name "EBECRYL 4141"). <Component (B)> · Component (B11-1): Plant-derived glycerin (manufactured by Sakamoto Yakuhin Kogyo Co., Ltd., product name "R-PG"). · Component (B21-1): Sorbitol-modified acrylate (manufactured by Toagosei Co., Ltd., product name "Aronix M-926"). · Component (B21-2): Soybean oil-modified epoxy acrylate (manufactured by Daicel Ornex Co., Ltd., product name "EBECRYL 5848"). <Component (C)> · Component (C21-1): Glycerin-modified acrylate (manufactured by Toagosei Co., Ltd., product name "Aronix M-920"). <Photoinitiator> · 1-Hydroxycyclohexyl phenyl ketone (manufactured by IGM, product name "Omn184"). <Reaction accelerator> · 1,8-Diazabicyclo[5.4.0]undecene-7 (DBU).

[0105]

Table 1

[0106] [Examples 1 to 3 and Comparative Examples 1 to 4] Using the above materials, each component was mixed at the compositions and content ratios shown in Table 2 to obtain a curable composition. For the obtained curable composition, curability and adhesion were evaluated under the following conditions. The results are shown in Table 2.

[0107] <Curability and adhesion evaluation> On the surface of a base PET film (thickness 100 μm), the curable composition was applied at 100 g / m 2It was coated. Then, a porous base paper (impregnated titanium base paper, manufactured by KJ Special Paper Co., Ltd.) was laminated, and the curable composition was impregnated into the porous base paper to obtain a paper layer. On the paper layer, the curable composition was further coated at 100 g / m 2 After coating, the outermost surface was covered with a protective PET film (thickness: 100 μm), and a laminate was obtained by laminating in the order of a base PET film / adhesive layer (curable composition) / paper layer / top coat layer (curable composition) / protective PET film. (Photo-curing evaluation) Ultraviolet rays were irradiated from the protective PET film side of the obtained laminate (light source: high-pressure mercury lamp, irradiation conditions: 2 kw, 4 m, 2 passes. Integrated light quantity: 800 mJ / cm 2 ) to cause photo-curing. Then, the protective PET film was peeled off, and the curability of the top coat layer was evaluated according to the following evaluation criterion 1. Also, the paper layer was peeled off, and the curability of the paper layer and the curability of the adhesive layer were evaluated according to evaluation criterion 2. (Evaluation criterion 1) A: There was no tack when touching the top coat layer with a finger. B: There was tack when touching the top coat layer with a finger. (Evaluation criterion 2) A: The base PET film and the paper layer were adhered (the paper layer and the adhesive layer were cured). B: The base PET film and the paper layer were not adhered (the paper layer and the adhesive layer were not cured). (Photo-curing and heat-curing evaluation) After the obtained laminate was photo-cured under the same conditions as above, it was put into an oven at 80 °C, and the time until all layers were cured was measured. After the heat-curing was completed, the protective PET film was peeled off, and the curability of the top coat layer was evaluated according to the above evaluation criterion 1. Also, the paper layer was peeled off, and the curability of the paper layer and the curability of the adhesive layer were evaluated according to the above evaluation criterion 2. Furthermore, the curability in photo-curing and heat-curing was evaluated according to the following evaluation criterion 3. (Evaluation criterion 3) Pass: All of the top coat layer, the paper layer, and the adhesive layer were cured, and the time required for heat-curing was less than 30 minutes. Non - compliance: Any one of the top - coat layer, paper layer, or adhesive layer was not cured, or although all layers were cured, the time required for thermosetting was 30 minutes or more. (Adhesion evaluation) After the above - mentioned photocuring and thermosetting, the peelability when peeling the paper layer from the base PET film was evaluated in five grades. Regarding "0 evaluation" as the uncured state and "5 evaluation" as the most adhered (difficult to peel), the peelability between the paper layer and the base PET film was evaluated as 0, 1, 2, 3, 4, 5, and 4 or more was regarded as qualified.

[0108]

Table 2

[0109] As shown in Table 2, in Examples 1 - 4 that satisfied the composition of the curable composition according to the first embodiment, all of the top - coat layer, paper layer, and adhesive layer were cured by photocuring and thermosetting. Furthermore, the time required for thermosetting was also less than 30 minutes. On the other hand, for the curable compositions of Comparative Examples 1 - 3 that did not contain component (B), although the top - coat layer was cured by photocuring, the paper layer and the adhesive layer did not cure even after heating for 60 minutes or more. Also, for the curable composition of Comparative Example 4 that did not contain a (meth)acryloyl group, although the paper layer and the adhesive layer were cured by photocuring and thermosetting, the top - coat layer did not cure. It is considered that in order to completely cure the curable composition of Comparative Example 4, it is necessary to perform hot pressing or thermosetting under higher - temperature conditions. From the above results, it was found that the curable composition according to the first embodiment can be cured with less thermal energy than before. Furthermore, as shown in Examples 1 - 4, by adopting materials derived from biomass, it is also possible to obtain a curable composition that is environmentally friendly with less petroleum - derived components. Such curable compositions and / or cured products can be suitably used as impregnating resins for decorative papers and decorative boards. They can also be suitably used as curable compositions for adhesive layers and top - coat layers.

Explanation of symbols

[0110] 1: Porous base paper 2: Top - coat layer 3: Adjacent layer 10: Cosmetic paper 20: Substrate 100: Cosmetic board

Claims

1. A curable composition comprising a curable component and a photoinitiator, wherein the curable component comprises at least one (meth)acryloyl group-containing polyisocyanate component (A2) containing at least two isocyanate groups and at least one (meth)acryloyl group, and one or more selected from a polyol component (B1) containing at least two hydroxyl groups, and a (meth)acryloyl group-containing polyol component (B2) containing at least two hydroxyl groups and at least one (meth)acryloyl group.

2. The curable composition according to Claim 1, wherein the proportion of the biomass-derived component relative to the total mass of the curable component is 10% by mass or more.

3. The curable composition according to Claim 1 or 2, wherein the curable component further comprises a (meth)acrylate component (C) containing at least one (meth)acryloyl group.

4. The curable composition according to Claim 1 or 2, wherein the average hydroxyl equivalent of the component (B1) is 30 to 5,000.

5. The curable composition according to Claim 1 or 2, wherein the isocyanate index (average isocyanate group equivalent / average hydroxyl group equivalent) of the curable component is 0.01 to 2.

0.

6. A cured product of the curable composition according to Claim 1.

7. A laminate comprising one or more layers selected from the curable composition according to Claim 1 and the cured product according to Claim 6.

8. The laminate according to Claim 7, which is a resin-impregnated decorative paper or a resin-impregnated decorative board.

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