Active energy ray-curable resin composition

Abstract

The present invention provides a cured film surface showing excellent tack-free properties. As a solution, an active energy ray-curable resin composition characterized by containing (A) urethane acrylate having a polytetramethylene ether skeleton and / or a polytrimethylene ether skeleton, (B) at least one photopolymerization initiator selected from the group consisting of benzophenone derivatives, methylbenzoylformate derivatives, and α-hydroxyacetophenone derivatives, (C) fumed silica, and (D) a reactive diluent having a (meth)acryl group, wherein the content of the fumed silica (C) is 4 mass parts or more when the total of the (A) component and the (D) component is 100 mass parts, and the surface tack of a cured film obtained by curing in the presence of air with 365 nm LED light is 20 gf / cm 2 The following.

Description

Technical Field

[0001] This invention relates to active energy ray-curable resin compositions. Background Technology

[0002] Previously, active energy ray-cured resin compositions were widely used in coating applications and cured liquid gasket (CIPG) applications because they could cure in a short time.

[0003] In active energy ray-curable resin compositions used in the aforementioned applications, when the cured surface is exposed to air (oxygen) during photocuring, oxygen inhibition occurs, resulting in an uncured or sticky surface. Particularly in active energy ray-curable resin compositions used for coating or CIPG applications, a tack-free cured surface is required to prevent stains from adhering to the cured surface and substrate adhesion.

[0004] As such active energy ray-curable resin compositions, a photocurable composition containing a specific component, an elastomer (A), a monomer having a (meth)acryloyl group (B), a photopolymerization initiator (C), etc., has been proposed (see, for example, Patent Document 1).

[0005] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2022-174718 Summary of the Invention

[0006] The problem that the invention aims to solve However, the photocurable composition described in Patent Document 1 does not exhibit sufficient non-stickiness. The photocurable composition described in Patent Document 1 uses a metal halide lamp with strong curing power for curing (see paragraph 0074 of Patent Document 1), and therefore cannot exhibit practically usable non-stickiness when cured using a narrow wavelength light source with low energy levels, such as an LED, resulting in insufficient non-stickiness.

[0007] Therefore, it is desirable to develop active energy ray-cured resin compositions that exhibit excellent non-stickiness on the surface of the cured film.

[0008] The purpose of this invention is to provide an active energy ray-cured resin composition that exhibits excellent non-stickiness on the surface of the cured film.

[0009] Technical solutions for solving the problem The inventors of this invention conducted repeated and in-depth research and discovered that the above-mentioned objective can be achieved using the following active energy ray-curable resin composition, thereby completing this invention. The above-mentioned active energy ray-curable resin composition contains specific components (A) to (D). When the total mass of components (A) and (D) is 100 parts by mass, the content of fumed silica as component (C) is 4 parts by mass or more. The surface viscosity of the cured film obtained by curing with 365 nm LED light in the presence of air is 20 gf / cm². 2 the following.

[0010] That is, the present invention relates to the following active energy ray-curable resin composition.

[0011] 1. An active energy ray-curable resin composition, characterized in that it contains the following components (A), (B), (C), and (D), (A) Uratrix acrylates having a polytetramethylene ether backbone and / or a polytrimethylene ether backbone, (B) At least one photopolymerization initiator selected from benzophenone derivatives, methyl benzoate derivatives, and α-hydroxyacetophenone derivatives. (C) Fumed silica, (D) Reactive diluents with (meth)acryloyl groups, When the total of component (A) and component (D) is 100 parts by mass, the content of fumed silica (C) is 4 parts by mass or more. The surface viscosity of the cured film obtained by curing with 365 nm LED light in the presence of air was 20 gf / cm. 2 the following.

[0012] 2. The active energy ray-curable resin composition as described in item 1, wherein the polytetramethylene ether backbone of component (A) is polytetramethylene ether.

[0013] 3. The active energy ray-curable resin composition as described in item 1 or 2, wherein the backbone of the polyisocyanate in component (A) is derived from an aliphatic polyisocyanate.

[0014] 4. The active energy ray-curable resin composition as described in item 1 or 2, wherein the backbone of the polyisocyanate of component (A) is derived from isophorone diisocyanate derivatives and / or 4,4'-methylene bis(cyclohexyl isocyanate) derivatives.

[0015] 5. The active energy ray-curable resin composition according to any one of items 1 to 4, wherein the above-mentioned (D) component, when the total of the above-mentioned (D) component is 100% by mass, contains 10% by mass and less than 100% by mass of a reactive diluent having an SP value of 9.1 or less calculated by the Fedors formula.

[0016] 6. The active energy ray curable resin composition according to any one of items 1 to 4, wherein the (D) component contains 0% or more and less than 10% by mass of a reactive diluent having a (meth)acrylyl group with an SP value of 9.1 or less calculated by Fedors formula when the total (D) component is 100% by mass, and the (C) component contains methacryl-modified fumed silica.

[0017] Invention Effects The cured film surface of the active energy ray-curable resin composition of the present invention exhibits excellent non-stickiness. Detailed Implementation

[0018] The present invention will now be described in detail.

[0019] 1. Active energy ray-curable resin composition The active energy ray-curable resin composition of the present invention is an active energy ray-curable resin composition containing the following components (A), (B), (C), and (D), wherein (A) is an urethane acrylate having a polytetramethylene ether backbone and / or a polytrimethylene ether backbone, (B) is at least one photopolymerization initiator selected from benzophenone derivatives, methyl benzoylformate, and α-hydroxyacetophenone derivatives, (C) is fumed silica, and (D) is a reactive diluent having (meth)acryloyl groups. When the total of components (A) and (D) is 100 parts by mass, the content of fumed silica (C) is 4 parts by mass or more, and the surface tack of the cured film obtained by curing with 365 nm LED light in the presence of air is 20 gf / cm. 2 The active energy ray curable resin composition having the above characteristics contains the above-mentioned specific components (A) to (D), and the content of (C) fumed silica is 4 parts by mass or more when the total of components (A) and (D) is 100 parts by mass. The cured film surface can exhibit excellent non-stickiness.

[0020] In recent years, non-stick coating technology has achieved non-stick properties by combining multifunctional acrylates, high-melting-point materials, and high-Tg materials. However, the cured products obtained by these technologies have high hardness, making them unsuitable for applications requiring flexibility, such as conformal coatings and CIPG.

[0021] The active energy ray-curable resin composition of the present invention contains the specific components (A) to (D) described above, and the content of fumed silica (C) is 4 parts by mass or more when the total mass of components (A) and (D) is 100 parts by mass. The cured film surface exhibits excellent non-stickiness, eliminating the need for strong curing metal halide lamps; curing can be performed using light sources with weak curing effects, such as LED lamps, and a sufficiently non-sticky cured surface can be obtained. The active energy ray-curable resin composition of the present invention particularly benefits the cured product by containing component (D), which imparts flexibility, and further enhances its excellent non-stickiness by also containing the aforementioned components (A) to (C).

[0022] Furthermore, since the active energy ray curable resin composition of the present invention has the above-described structure, it does not require the use of (meth)acrylate monomers with high glass transition temperatures. Therefore, the cured film exhibits excellent flexibility and low-temperature properties.

[0023] The active energy ray-curable resin composition of the present invention will be described in detail below.

[0024] The surface tack of the cured film obtained by curing the active energy radiation-curable resin composition of the present invention with 365 nm LED light in the presence of air is 20 gf / cm. 2 The following applies if the surface tack of the cured film exceeds 20 gf / cm. 2 Otherwise, sufficient non-stickiness cannot be exhibited. The preferred surface tack is 18 gf / cm³. 2 Below, 15 gf / cm is preferred. 2 Below, 10 gf / cm is preferred. 2 The following is a preferred option: 8 gf / cm 2 The optimal value is 5 gf / cm. 2 The next optimal value is 2 gf / cm. 2 The following is a summary of the points below. Additionally, the lower limit of the surface viscosity mentioned above is not specifically limited; the lower the better, for example, 0.1 gf / cm³. 2 0.5 gf / cm 2 1gf / cm 2 2 gf / cm 2 3 gf / cm 2 wait.

[0025] The surface tack of the cured active energy ray-curable resin composition of the present invention was measured by the following method.

[0026] Surface tack of the cured film An active energy radiation-curable resin composition was dropped onto a polyethylene terephthalate (PET) film, and a liquid film with a width of 50 mm and a thickness of 0.5 mm was prepared using a film applicator. The liquid film was then irradiated with an intensity of 300 mW / cm² in the presence of air. 2 Cumulative light intensity 18000 mJ / cm 2 A cured film was prepared by irradiating the film with 365 nm LED light. The cured film was then fixed in place, and a 24 mm diameter stainless steel cylinder was pressed against its surface with a force of 1.1 kgf for 1 minute. The cylinder was then lifted vertically at a speed of 5 mm / min to peel it off the cured film. The maximum force (gf) applied during peeling was measured and divided by the surface area of ​​the cylinder's contact surface (12 x 12 x π = 452 mm²). 2 ), from which the surface viscosity value (gf / cm) can be calculated. 2 ).

[0027] The components constituting the active energy ray-curable resin composition of the present invention will be described in detail below.

[0028] (A) Ingredients (A) The component is an urethane acrylate having a polytetramethylene ether backbone and / or a polytrimethylene ether backbone.

[0029] As for the aforementioned urethane acrylates with a polytetramethylene ether backbone, there is no particular limitation as long as the structure has at least one polytetramethylene ether backbone. In addition to the polytetramethylene ether backbone, it may also have a polyamide backbone, a polyester backbone, or other backbones, as long as it does not impair the effect of the present invention. Furthermore, the structure may also have functional groups such as hydroxyl groups.

[0030] The polytetramethylene ether skeleton described above can be specifically listed as the skeleton shown in formula (1) below. In equation (1), A 1 ~A 8 "Same" or "different" indicates alkyl groups such as hydrogen, methyl, ethyl, propyl (n-propyl, isopropyl), butyl (n-butyl, isobutyl, sec-butyl, tert-butyl), n-pentyl, etc.; halogen groups such as chlorine, bromine, fluorine, etc.; and hydroxyl, carboxyl, amino, cyano, nitro, etc. Additionally, n represents an integer greater than 1, and * indicates a valence bond.

[0031] In the above formula (1), A 1 ~A 8 Whether the functional groups are the same or different, the preferred functional group is one that does not contain active hydrogen, more preferably hydrogen or a hydrocarbon group, and even more preferably hydrogen.

[0032] In the above formula (1), n ​​is preferably a natural number from 1 to 60, more preferably a natural number from 3 to 56, even more preferably a natural number from 9 to 42, particularly preferably a natural number from 9 to 28, and most preferably a natural number from 9 to 14.

[0033] The molecular weight of the polyol constituting component (A) is not particularly limited, but is preferably 200 to 4,000, more preferably 250 to 3,000, even more preferably 650 to 2,000, and most preferably 650 to 1,000. By having the molecular weight of the constituting polyol within the above range, viscosity can be reduced.

[0034] As the polyether used to form the aforementioned polytetramethylene ether backbone, polytetramethylene ether glycol or a polytetramethylene ether glycol derivative is preferred. Among these, polytetramethylene ether glycol is preferred from the viewpoint that the surface of the film cured by the active energy ray-curable resin composition exhibits superior non-stickiness.

[0035] As for the aforementioned urethane acrylates with a polytrimethylene ether backbone, there is no particular limitation as long as the structure has at least one polytrimethylene ether backbone. In addition to the polytrimethylene ether backbone, it may also have a polyamide backbone, a polyester backbone, or other backbones, as long as it does not impair the effect of the present invention. In addition, the structure may also have functional groups such as hydroxyl groups.

[0036] The above-mentioned polytrimethylene ether skeleton can be specifically listed as the skeleton shown in formula (2) below. In equation (2), B 1 ~B 6 "Same" or "different" indicates alkyl groups such as hydrogen, methyl, ethyl, propyl (n-propyl, isopropyl), butyl (n-butyl, isobutyl, sec-butyl, tert-butyl), n-pentyl, etc.; halogen groups such as chlorine, bromine, fluorine, etc.; and hydroxyl, carboxyl, amino, cyano, nitro, etc. Additionally, n represents an integer greater than 1, and * indicates a valence bond.

[0037] In the above formula (2), B 1 ~B 6 Whether the groups are the same or different, it is preferred to indicate functional groups that do not contain active hydrogen, more preferably to indicate hydrogen or hydrocarbon groups, and even more preferably to indicate hydrogen.

[0038] In the above formula (2), n is preferably a natural number from 1 to 70, more preferably a natural number from 4 to 69, even more preferably a natural number from 11 to 52, particularly preferably a natural number from 11 to 39, and most preferably a natural number from 11 to 20.

[0039] Examples of polyethers used to form the aforementioned polytrimethylene ether backbone include polytrimethylene glycol and polytrimethylene glycol derivatives. Among these, polytrimethylene glycol is preferred from the viewpoint that the surface of the film cured by the active energy ray-curable resin composition exhibits superior non-stickiness.

[0040] The above component (A) may have a polytetramethylene ether backbone and a polytrimethylene ether backbone separately, or it may have both.

[0041] The urethane acrylate of component (A) has a polyisocyanate backbone, which, together with the aforementioned polytetramethylene ether backbone and / or polytrimethylene ether backbone, constitutes component (A). The polyisocyanate backbone constituting component (A) is preferably an aliphatic polyisocyanate backbone derived from an aliphatic polyisocyanate. By using an aliphatic polyisocyanate backbone, the flexibility of the cured film of the active energy ray-curable resin composition is improved, and yellowing of the film can be suppressed.

[0042] Examples of aliphatic polyisocyanate skeletons include isophorone diisocyanate skeletons derived from isophorone diisocyanate derivatives and 4,4'-methylene bis(cyclohexyl isocyanate) skeletons derived from 4,4'-methylene bis(cyclohexyl isocyanate) derivatives. Among these, the 4,4'-methylene bis(cyclohexyl isocyanate) skeleton is preferred.

[0043] (A) The component may have one of the above-mentioned polyisocyanate skeletons alone, or may have two or more of the above-mentioned polyisocyanate skeletons mixed together.

[0044] When the active energy ray-curable resin composition is 100% by mass, the content of component (A) is preferably 1-50% by mass, more preferably 4-50% by mass, even more preferably 4-40% by mass, even more preferably 4-35% by mass, even more preferably 9-30% by mass, and even more preferably 11-27% by mass. When the lower limit of the content of component (A) is within the above range, the surface of the cured film of the active energy ray-curable resin composition exhibits superior non-stickiness. When the upper limit of the content of component (A) is within the above range, the viscosity of the active energy ray-curable resin composition becomes a suitable viscosity, and the coatability is further improved.

[0045] Relative to the total of component (A) and component (D) described later, the content of component (A) is preferably 1 to 50% by mass, more preferably 5 to 50% by mass, even more preferably 5 to 40% by mass, even more preferably 5 to 35% by mass, even more preferably 10 to 30% by mass, and even more preferably 12 to 28% by mass. When the lower limit of the content of component (A) is within the above range, the surface of the cured film of the active energy ray-curable resin composition exhibits superior non-stickiness. When the upper limit of the content of component (A) is within the above range, the viscosity of the active energy ray-curable resin composition becomes a suitable viscosity, and the coatability is further improved.

[0046] The number of functional groups in component (A) is preferably 1.5 to 2.5, more preferably 1.8 to 2.2, even more preferably 1.9 to 2.1, and most preferably 2.0. When the lower limit of the number of functional groups in component (A) is within the above range, the surface of the cured film of the active energy ray-curable resin composition exhibits superior non-stickiness. When the upper limit of the number of functional groups in component (A) is within the above range, the elongation of the active energy ray-curable resin composition is further improved.

[0047] The concentration of the (meth)acryloyl functional group in component (A) is not particularly limited, but is preferably 0.125–2.000 mmol / g, more preferably 0.125–0.500 mmol / g, even more preferably 0.153–0.280 mmol / g, and most preferably 0.180–0.220 mmol / g. When the lower limit of the functional group concentration of component (A) is within the above range, the viscosity of the active energy ray-curable resin composition becomes a suitable viscosity, and the coatability is further improved. When the upper limit of the number of functional groups in component (A) is within the above range, the elongation of the active energy ray-curable resin composition is further improved.

[0048] The synthesis method of the urethane acrylate as component (A) can use existing known methods without particular limitation. For example, an oligomer formed by combining a hydroxyl compound having a (meth)acryloyl group with a diisocyanate compound at both ends of a polyol can be used, or an oligomer combining an isocyanate compound having a (meth)acryloyl group can be used.

[0049] (B) Components (B) is at least one photopolymerization initiator selected from benzophenone derivatives, methyl benzoate derivatives, and α-hydroxyacetophenone derivatives. By containing the above-mentioned component (B), free radicals can be generated using light, effectively initiating free radical polymerization.

[0050] Specific examples of benzophenone derivatives include: benzophenone, 4-methylbenzophenone, 4-phenylbenzophenone, and 4-(p-tolylthio)benzophenone.

[0051] Specific examples of methyl benzoylcarbamate derivatives include: methyl benzoylcarbamate, ethyl benzoylcarbamate, methyl 2-methylbenzoylcarbamate, methyl 3-methylbenzoylcarbamate, methyl 4-methylbenzoylcarbamate, etc.

[0052] Specific examples of α-hydroxyacetophenone derivatives include: 2-hydroxy-2-methylphenylacetone, 1-hydroxycyclohexylphenyl ketone, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylphenylacetone, 2,2'-dihydroxy-2,2'-dimethyl-1,1'-[methylenebis(4,1-phenylene)]bis(prop-1-one), etc.

[0053] Of the above, from the viewpoint of being able to more effectively initiate polymerization, benzophenone derivatives and α-hydroxyacetophenone derivatives are preferred, and benzophenone derivatives are more preferred.

[0054] The above-mentioned component (B) can be used alone or in combination of two or more.

[0055] The content of component (B) is preferably 0.1 to 15 parts by mass relative to the total of 100 parts by mass of component (A) and component (D) described later, more preferably 0.5 to 10 parts by mass, and even more preferably 1 to 5 parts by mass. By keeping the content of component (B) within the above range, the hardness of the cured active energy ray-curable resin composition can be appropriately adjusted, and the surface of the cured film can exhibit better non-stickiness.

[0056] (C) Components (C) The component is fumed silica.

[0057] In this invention, when the total of component (A) and component (D) described later is 100 parts by mass, the content of component (C) is 4 parts by mass or more. If the content of component (C) is less than 4 parts by mass, the non-stickiness of the film surface after curing the active energy ray curable resin composition decreases. The content of component (C) is preferably 4.5 parts by mass or more, more preferably 5 parts by mass or more, and even more preferably 7 parts by mass or more. In addition, there is no particular upper limit to the content of component (C), and when the total of components (A) and (D) is 100 parts by mass, it can be 20 parts by mass, 15 parts by mass, or 10 parts by mass.

[0058] There are no particular limitations on the fumed silica; known fumed silica such as hydrophilic fumed silica with a large number of hydrophilic silanol groups (Si-OH) on its surface, and hydrophobic fumed silica with silanol groups on its surface capped by alkylsilanes and / or dimethylpolysiloxanes can be used.

[0059] The surface of fumed silica can be modified. Examples of such modifications include methacrylamide modification and amino modification. Among these, methacrylamide modification is preferred in that it enables the cured film surface of the active energy ray-curable resin composition to exhibit superior non-stickiness.

[0060] The average primary particle size of the fumed silica is preferably 5 nm to 50 μm. By using such fumed silica, the active energy ray-curable resin composition of the present invention can be endowed with good thixotropic properties and excellent coatability. In addition, the active energy ray-curable resin composition of the present invention can be made transparent, and sufficient curing properties can be obtained even when irradiated with ultraviolet light or the like.

[0061] (D) Component Component (D) is a reactive diluent having a (meth)acryloyl group. By containing component (D) above, the cured product of the active energy ray-curable resin composition becomes soft. Therefore, the active energy ray-curable resin composition of the present invention exhibits excellent non-stickiness on the film surface despite the softness of the cured product.

[0062] (D) Components containing (meth)acryloyl groups are not particularly limited as long as they function as reactive diluents. Examples of such reactive diluents include monofunctional (meth)acrylate monomers with one unsaturated bond in the molecule.

[0063] Furthermore, in this specification, "reactive diluent" refers to a diluent with a viscosity of 2000 mPa·s or less at 23°C. The viscosity of component (D) is preferably 1000 mPa·s or less, more preferably 500 mPa·s or less, even more preferably 300 mPa·s or less, particularly preferably 200 mPa·s or less, and most preferably 100 mPa·s or less. By ensuring that the upper limit of the viscosity of component (D) is within the above range, the viscosity of the active energy ray-curable resin composition becomes a suitable viscosity, further improving its coatability.

[0064] Specific examples of the aforementioned monofunctional (meth)acrylate monomers include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, hexyl methacrylate, 2-ethylhexyl methacrylate, 1-ethylheptyl methacrylate, nonyl methacrylate, isononyl methacrylate, 1-butylpentyl methacrylate, lauryl methacrylate, octadecyl methacrylate, etc. (meth)acrylate chain alkyl esters, or isobornyl methacrylate, cyclohexyl methacrylate, dicyclopentenyl methacrylate, dicyclopentyl methacrylate, phenoxy polyethylene glycol (meth)acrylate, nonylphenoxy polyethylene glycol (meth)acrylate, tetrahydrofurfuryl methacrylate, phenoxy methacrylate, phenoxy methacrylate, phenoxy ethyl methacrylate, etc. (Meth)acrylates with cyclic structures, such as alkylphenoxy acrylate and alkylphenoxyethyl methacrylate; hydroxyalkyl methacrylates with hydroxyl groups, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, and 2-hydroxylauryl (meth)acrylate, or 2-hydroxy-3-phenoxypropyl acrylate; and mono(meth)acrylates of oligo or polyoxyalkylene glycols, such as diethylene glycol mono(meth)acrylate, triethylene glycol mono(meth)acrylate, polyethylene glycol mono(meth)acrylate, dipropylene glycol mono(meth)acrylate, trimethylene glycol mono(meth)acrylate, and polypropylene glycol (meth)acrylate. These can be used alone or in combination with two or more.

[0065] Among these, at least one of the following is preferred: (meth)acrylate monomers having a non-cyclic (linear or branched) hydrocarbon structure; (meth)acrylate monomers having a cyclic structure such as an aromatic backbone; (meth)acrylate monomers having an aromatic backbone and modified with ethylene oxide; and (meth)acrylate monomers having heterocycles such as tetrahydrofuran in their molecules. From the viewpoint that the cured product of an active energy ray-curable resin composition becomes more flexible, (meth)acrylate monomers having a non-cyclic (linear or branched) hydrocarbon structure in their molecules are particularly preferred.

[0066] Examples of (meth)acrylate monomers having a noncyclic (straight-chain or branched-chain) hydrocarbon structure include n-butyl (meth)acrylate, n-octyl (meth)acrylate, lauryl (meth)acrylate, and isodecanyl (meth)acrylate. Examples of (meth)acrylates having an aromatic backbone and modified with ethylene oxide include phenoxy polyethylene glycol (meth)acrylate and nonylphenoxy polyethylene glycol (meth)acrylate. Examples of (meth)acrylate monomers having a cyclic structure such as an aromatic backbone include phenoxy ethyl (meth)acrylate.

[0067] Among these, phenoxy polyethylene glycol (meth)acrylate and isodecyl (meth)acrylate are particularly preferred.

[0068] The SP value of component (D), calculated using the Fedor's formula, is preferably 9.1 or less, more preferably 9.0 or less, even more preferably 8.9 or less, and particularly preferably 8.8 or less. When the lower limit of the SP value of component (D) is within the above range, the surface of the film after curing the active energy ray-curable resin composition exhibits superior non-stickiness. Furthermore, the lower limit of the above SP value is not particularly limited, and for example, it is 8.0, 8.3, 8.7, etc.

[0069] Furthermore, the SP value of component (D), calculated using the Fedors formula, can exceed 9.1. Even when the SP value exceeds 9.1, when component (C) contains methacrylamide-modified fumed silica, the surface of the cured film of the active energy ray-curable resin composition exhibits superior non-stickiness. The lower limit of the SP value of component (D) is, for example, 9.2, 9.3, 9.4, 9.5, etc. The upper limit of the SP value of component (D) is, for example, 11.0, 10.8, 10.5, 10.3, 10.2, etc.

[0070] When the total content of component (D) is 100% by mass, component (D) preferably contains 10% by mass and 100% by mass of a reactive diluent having a (meth)acryloyl group and an SP value of 9.1 or less calculated by Fedors formula. When the content of the reactive diluent having a (meth)acryloyl group and an SP value of 9.1 or less is within the above-mentioned range, the surface of the cured film of the active energy ray-curable resin composition exhibits superior non-stickiness. Furthermore, the higher the content of the reactive diluent having a (meth)acryloyl group and an SP value of 9.1 or less relative to the total content of component (D), the superior non-stickiness is exhibited, which is advantageous. Moreover, when component (D) contains a reactive diluent having a (meth)acryloyl group and an SP value of 9.1 or less calculated by Fedors formula within the above-mentioned content range, the remaining portion of component (D) may be a reactive diluent having a (meth)acryloyl group and an SP value exceeding 9.1 calculated by Fedors formula.

[0071] When component (D) contains 0% to less than 10% by mass of a reactive diluent with a (meth)acrylyl group and an SP value of 9.1 or less calculated by Fedors formula, when component (D) is 100% by mass, component (C) is preferably methacryl-modified fumed silica. In this case, by making component (C) methacryl-modified fumed silica, the surface of the cured film of the active energy ray-curable resin composition can exhibit superior non-stickiness. Furthermore, when component (C) contains methacryl-modified fumed silica, and component (D) contains a reactive diluent with a (meth)acrylyl group and an SP value of 9.1 or less calculated by Fedors formula within the above range, the remaining portion of component (D) can be a reactive diluent with a (meth)acrylyl group and an SP value exceeding 9.1 calculated by Fedors formula.

[0072] The glass transition temperature (Tg) of component (D) is preferably -80 to 15°C, more preferably -70 to 10°C, even more preferably -70 to 0°C, even more preferably -70 to -10°C, and even more preferably -70 to -20°C. By ensuring that the glass transition temperature of component (D) is within the above range, the cured product obtained by curing the active energy ray-curable resin composition of the present invention exhibits moderate flexibility, making it suitable for coating applications or CIPG applications.

[0073] Of 100% by mass of the total of components (A) and (D), the content of component (D) is preferably 50 to 99% by mass, more preferably 60 to 95% by mass, and even more preferably 70 to 90% by mass. By keeping the content of component (D) within the above range, the hardness and viscosity of the cured active energy ray-curable resin composition can be appropriately adjusted.

[0074] Other ingredients The active energy ray-curable resin composition of the present invention may be appropriately supplemented with polymerization inhibitors, adhesion promoters, leveling agents, defoamers, antioxidants, flame retardants, etc., depending on its purpose.

[0075] The glass transition temperature (Tg) of the cured product after curing the active energy ray-curable resin composition of the present invention is preferably -50 to 30°C, more preferably -40 to 10°C, and even more preferably -40 to 0°C. With the glass transition temperature within the above range, the cured product exhibits moderate flexibility, making it suitable for coating applications or CIPG applications. By having the above-described structure, the active energy ray-curable resin composition of the present invention not only provides flexibility but also exhibits excellent non-stickiness on the surface of the cured film.

[0076] In addition, the glass transition temperature (Tg) of the cured product in this specification is determined by the following method.

[0077] Methods for determining the glass transition temperature (Tg) of cured products An active energy radiation-curable resin composition was dropped onto a polyethylene terephthalate (PET) film after demolding, and a liquid film with a width of 50 mm and a thickness of 0.5 mm was formed using a coating applicator. The liquid film was then irradiated with an intensity of 300 mW / cm² in the presence of air. 2 Cumulative light intensity 18000 mJ / cm 2 A cured film was prepared by irradiating the film with 365 nm LED light. The cured film was then cut into strips of 4 mm × 32 mm to prepare test pieces. The dynamic viscoelasticity was measured using these test pieces, and the temperature at which the tanδ peak was displayed was taken as the glass transition temperature (Tg) of the cured product. The dynamic viscoelasticity was measured in tensile mode at a frequency of 1 Hz and a temperature increase rate of 5 °C / min from -80 to 130 °C.

[0078] The method for manufacturing the active energy ray-curable resin composition of the present invention is not particularly limited and can be manufactured using conventional methods. For example, it can be manufactured by mixing the above-mentioned components (A) to (D) and other components as needed using a temperature-adjustable mixer such as a planetary mixer, a twin-shaft mixer, a high-shear mixer, a butterfly mixer, or a rotation-revolution mixer.

[0079] The embodiments of the present invention have been described above, but the present invention is not limited to such examples in any way, and can of course be implemented in various ways without departing from the spirit of the present invention.

[0080] Example The present invention will now be described in more detail with reference to embodiments and comparative examples. However, the present invention is not limited to these embodiments.

[0081] Furthermore, the raw materials used in the examples and comparative examples are as follows.

[0082] (A) Ingredients (A) The urethane acrylates (A-1) to (A-19) of components (A) were synthesized according to the following steps. The liquid temperature of the polyol (a1) was adjusted to 60-70°C. Polyisocyanate (a2) and bismuth catalyst (manufactured by Nitto Kasei Corporation, product name: NEOSTANN U-600) were added to it, and the reaction was carried out at 100°C to obtain intermediate (a3). Then, 2-acryloyloxyethyl isocyanate (Karenz AOI manufactured by Resonac Corporation) and bismuth catalyst were added as (meth)acrylate esterifying agents, and the reaction was further carried out to obtain the desired urethane acrylate.

[0083] The feeding ratio of polyol (a1) to polyisocyanate (a2) was such that the hydroxyl value of intermediate (a3) ​​was 0.206 mmol / g. Furthermore, the feeding amount of 2-acryloyloxyethyl isocyanate was such that the concentration of the (meth)acryloyl functional group of the urethane acrylate was 0.200 mmol / g or less.

[0084] • (A-1): urethane acrylate (polyether), a1 = polytetramethylene glycol (manufactured by Mitsubishi Chemical Corporation, product name: PTMG-1000) (molecular weight 1,000), a2 = 4,4'-methylene dicyclohexyl diisocyanate (H 12 MDI (manufactured by Covestro, product name: Desmodur W), with a (meth)acryloyl functional group concentration of 0.200 mmol / g. • (A-2): urethane acrylate (polyether), a1 = modified polytetramethylene glycol (manufactured by Hodogaya Chemical Co., Ltd., product name: PTG-L1000) (molecular weight 1,000), a2 = 4,4'-methylene dicyclohexyl diisocyanate (manufactured by Covestro, product name: Desmodur W), (meth)acryloyl functional group concentration 0.200 mmol / g • (A-3): urethane acrylate (polyether), a1 = polytrimethylene glycol (manufactured by Austin Chemical Company, product name: Velvetol H1000) (molecular weight 1,000), a2 = 4,4'-methylene dicyclohexyl diisocyanate (manufactured by Covestro, product name: Desmodur W), (meth)acryloyl functional group concentration 0.200 mmol / g • (A-4): urethane acrylate (polyether), a1 = polypropylene glycol (manufactured by AGC, product name: EXCENOL 1020) (molecular weight 1,000), a2 = 4,4'-methylene dicyclohexyl diisocyanate (manufactured by Covestro, product name: Desmodur W), (meth)acryloyl functional group concentration 0.200 mmol / g • (A-5): A polyester polyol composed of urethane acrylate (polyester), a1=3-methyl-1,5-pentanediol and adipic acid (manufactured by Kuraray, product name: Kuraray Polyol P1010) (molecular weight 1,000), a2=4,4'-methylene dicyclohexyl diisocyanate (manufactured by Covestro, product name: Desmodur W), and a (meth)acryloyl functional group concentration of 0.200 mmol / g. • (A-6): urethane acrylate (conjugated diene), a1 = terminal hydroxyl-modified polybutadiene (manufactured by Cray Valley, product name: Krasol LBHP2000) (molecular weight 1,000), a2 = 4,4'-methylene dicyclohexyl diisocyanate (manufactured by Covestro, product name: Desmodur W), (meth)acryloyl functional group concentration 0.200 mmol / g • (A-7): Polycarbonate acrylate, polycarbonate polyol composed of a1=3-methyl-1,5-pentanediol and 1,6-hexanediol (manufactured by Kuraray, product name: Kuraray Polyol C-1090) (molecular weight 1,000), a2=4,4'-methylene dicyclohexyl diisocyanate (manufactured by Covestro, product name: Desmodur W), and a (meth)acryloyl functional group concentration of 0.200 mmol / g. • (A-8): Teleclaw type acrylic polymer (acryloyl-terminated polyacrylate), manufactured by Kaneka Corporation, product name XMAP RC100C • (A-9): Teleclaw-type acrylic polymer (terminated acryloyl-modified polyisobutylene), manufactured by Kaneka Corporation, product name EPION EP400V • (A-10)~(A-13): Same as (A-1) except that the molecular weight of a1 is set to 650, 2,000, 3,000 or 4,000 respectively.

[0085] • (A-14) to (A-18): The same as (A-1) except that the hydroxyl value of intermediate (a3) ​​is set to 0.281 mmol / g, 0.481 mmol / g, 1.903 mmol / g, 0.158 mmol / g or 0.132 mmol / g, respectively, and the functional group concentration of (meth)acryloyl group is set to 0.270 mmol / g, 0.450 mmol / g, 1.500 mmol / g, 0.155 mmol / g or 0.130 mmol / g, respectively.

[0086] • (A-19): Same as (A-1) except that a2 is set as isophorone diisocyanate (IPDI) (manufactured by Covestro, product name: Desmodur I).

[0087] (A) The urethane acrylate (A-20) of component (A) is synthesized by the following steps. The liquid temperature of the polyol (a1) is adjusted to 70–80 °C. Polyisocyanate (a2) is added to it and reacted at 70–80 °C to obtain intermediate (a3). Then, 2-hydroxyethyl acrylate (2HEA) and a bismuth catalyst are added as (meth)acrylate esterifying agents, and the reaction is further carried out to obtain the desired urethane acrylate.

[0088] The feeding ratio of polyol (a1) to polyisocyanate (a2) was such that the isocyanate group concentration of intermediate (a3) ​​was 0.206 mmol / g. Furthermore, the feeding amount of 2-hydroxyethyl acrylate (2HEA) was such that the concentration of the (meth)acryloyl functional group of the urethane acrylate was 0.200 mmol / g or less.

[0089] • (A-20): urethane acrylate (polyether), a1 = polytetramethylene glycol (manufactured by Mitsubishi Chemical Corporation, product name: PTMG-1000), a2 = 4,4'-methylene dicyclohexyl diisocyanate (manufactured by Covestro, product name: Desmodur W) (B) Components • (B-1): Benzophenone, manufactured by IGM Resins, product name Omnirad BP flakes • (B-2): 4-Methylbenzophenone, manufactured by IGM Resins, product name Omnirad 4MBP • (B-3): 4-Phenylacetone, manufactured by IGM Resins, product name Omnirad 4PBZ • (B-4): Methyl benzoylformate, manufactured by IGM Resins, product name Omnirad MBF • (B-5): 1-Hydroxycyclohexylphenyl ketone, manufactured by IGM Resins, product name Omnirad-184 • (B-6): 2-Hydroxy-2-methylphenylacetone, manufactured by IGM Resins, product name Omnirad-1173 • (B-7): 2,2-Dimethoxy-2-phenylacetophenone, manufactured by IGM Resins, product name Omnirad-651 • (B-8): 2-Benzyl-2-(dimethylamino)-4'-morpholinophenylbutanone, manufactured by IGM Resins, product name Omnirad-369 • (B-9): 2-Methyl-4'-(methylthio)-2-morpholinophenylacetone, manufactured by IGM Resins, product name Omnirad-907 • (B-10): Diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide, manufactured by IGM Resins, product name Omnirad-TPO (C) Components • (C-1): Hydrophilic fumed silica, manufactured by Tokuyama Corporation, product name Reolosil QS-20L • (C-2): Hydrophobic fumed silica, manufactured by Tokuyama Corporation, product name Reolosil MT-10 • (C-3): Methacrylamide-modified fumed silica, manufactured by Evonik, product name Aerosil R711 • (C-4): Calcium carbonate, manufactured by MARUO CALCIUM, product name Kalfine M-200 • (C-5): Zirconia microparticles, manufactured by Nippon Shokubai Co., Ltd., product name Zircostar HR-101 • (C-6): Halloysite, manufactured by FIMATEC, product name Dragonite HP-A (D) Component • (D-1): Aliphatic reactive diluent, linear C4, manufactured by Mitsubishi Chemical Corporation, product name butyl acrylate, SP value obtained by Fedors formula 8.82, Tg -55℃ • (D-2): Aliphatic reactive diluent, linear C8, manufactured by Osaka Organic Chemical Industry Co., Ltd., product name NOAA (n-octyl acrylate), SP value obtained by Fedors formula 8.74, Tg -65℃ • (D-3): Aliphatic reactive diluent, linear C12, manufactured by Osaka Organic Chemical Industry Co., Ltd., product name LA (laurate acrylate), SP value obtained by Fedors formula 8.70, Tg -23℃ • (D-4): Aliphatic reactive diluent, branched C8, manufactured by Mitsubishi Chemical Corporation, product name: 2-ethylhexyl acrylate, SP value obtained by Fedors formula: 8.62, Tg: -70℃ • (D-5): Aliphatic reactive diluent, branched C10, manufactured by Osaka Organic Chemicals Co., Ltd., product name IDAA (isodecyl acrylate), SP value obtained by Fedors formula: 8.61, Tg: -62℃ • (D-6): Polyether-based reactive diluent, manufactured by Kyoei Co., Ltd., product name: Light Acrylate EC-A (ethoxylated diethylene glycol acrylate), SP value obtained by Fedors formula: 9.08, Tg: -70℃ • (D-7): Alicyclic reactive diluent, manufactured by Osaka Organic Chemical Industry Co., Ltd., product name Viscoat #155, CHA (cyclohexyl acrylate), SP value obtained by Fedors formula 9.26, Tg -15℃ • (D-8): Heterocyclic reactive diluent, manufactured by Osaka Organic Chemicals Co., Ltd., product name Viscoat #150, THFA (tetrahydrofurfuryl acrylate), SP value obtained by Fedors formula 9.54, Tg -12℃ • (D-9): Contains aromatic reactive diluent, aromatic system, manufactured by Osaka Organic Chemical Industry Co., Ltd., product name Viscoat #160, BZA (benzyl acrylate), SP value obtained by Fedors formula 10.14, Tg 6℃ • (D-10): Contains aromatic reactive diluents, ether-based, manufactured by Kyoei Co., Ltd., product name: LightAcrylate PO-A (phenoxyethyl acrylate), SP value obtained by Fedors formula: 10.12, Tg: -22℃ (Examples and Comparative Examples) The above raw materials are added to a mixing mill equipped with a heating device in the proportions shown in Tables 1 to 6. The mixture is stirred and mixed at 20–60°C for 15–60 minutes to produce an active energy radiation-curable resin composition.

[0090] (Evaluation Method) The following evaluation was performed on the embodiments and comparative examples.

[0091] Surface tack of the cured film An active energy radiation-curable resin composition was dropped onto a polyethylene terephthalate (PET) film, and a liquid film with a width of 50 mm and a thickness of 0.5 mm was prepared using a coating applicator. The liquid film was then irradiated with an intensity of 300 mW / cm² in the presence of air. 2 Cumulative light intensity 18000 mJ / cm 2 A cured film was prepared by irradiating the film with 365 nm LED light. The cured film was then fixed in place, and a 24 mm diameter stainless steel cylinder was pressed against its surface with a force of 1.1 kgf for 1 minute. Next, the cylinder was lifted vertically at a speed of 5 mm / min to peel it off the cured film. The maximum force (gf) applied during peeling was measured and divided by the surface area of ​​the cylinder's contact surface (12 x 12 x π = 452 mm²). 2 ), from which the surface viscosity value (gf / cm) can be calculated. 2 ).

[0092] Glass transition temperature (Tg) of the cured product An active energy radiation-curable resin composition was dropped onto a polyethylene terephthalate (PET) film after demolding, and a liquid film with a width of 50 mm and a thickness of 0.5 mm was formed using a coating applicator. The liquid film was then irradiated with an intensity of 300 mW / cm² in the presence of air. 2 Cumulative light intensity 18000 mJ / cm 2 A cured film was prepared by irradiating the film with 365 nm LED light. The cured film was then cut into strips of 45 mm × 32 mm to prepare test pieces. The dynamic viscoelasticity was measured using these test pieces, and the temperature at which the tanδ peak was displayed was taken as the glass transition temperature (Tg) of the cured product. The dynamic viscoelasticity was measured in tensile mode at a frequency of 1 Hz and a temperature increase rate of 5 °C / min from -80 to 130 °C.

[0093] Method for determining the elongation of cured products An active energy radiation-curable resin composition was applied to a release PET film adhered to a glass plate in an area of ​​approximately 100 mm x 100 mm with a thickness of 1 mm. The applied resin composition was then subjected to an illuminance of 100 mW / cm². 2A cured film was prepared by irradiating the film with 365 nm LED light for 100 seconds. Dumbbell-shaped pieces (No. 3) were punched out from the cured film to form test specimens. The elongation at break of the dumbbell test specimens was determined based on JIS K 6251:2007 Vulcanized rubber and thermoplastic rubber—Determination of tensile properties. The test conditions were 23°C and a tensile speed of 500 mm / min.

[0094] Evaluation methods for coating properties An active energy ray-curable resin composition was filled into a UV barrier syringe (PSY-10EU-OR) manufactured by Musashi Engineering Co., Ltd., and degassed using a vacuum-type rotary mixer. Then, a floating scraper piston (FLP-10E) manufactured by Musashi Engineering Co., Ltd. was embedded into the syringe. A plastic needle (20 gauge, PN-20G-B) manufactured by Musashi Engineering Co., Ltd. was then attached to the tip of the syringe. The syringe filled with the resin composition was dispensed using a pneumatic pulse digital dispensing machine (ML-6000X) manufactured by Musashi Engineering Co., Ltd. Dispensing performance was evaluated according to the following criteria, based on the dispensing pressure required by the digital dispensing machine during dispensing.

[0095] 5: It can be discharged at a discharge pressure of less than 200 kPa.

[0096] 4. It can be discharged at a discharge pressure of more than 200 kPa and less than 250 kPa.

[0097] 3: It can be discharged at a discharge pressure of more than 250 kPa and less than 300 kPa.

[0098] 2: It can be discharged at a discharge pressure of more than 300 kPa and less than 350 kPa.

[0099] 1: Unable to be ejected at an ejection pressure of 350 kPa.

[0100] The results are shown in Tables 1-6. In addition, in Tables 1-6, the values ​​of the combination are expressed as parts by mass, with the total of components (A) and (D) being 100 parts by mass.

[0101] [Table 1] [Table 2] [Table 3] [Table 4] [Table 5] [Table 6]

Claims

1. An active energy ray-curable resin composition, characterized in that: It contains the following components: (A), (B), (C), and (D). (A) Uratrix acrylates having a polytetramethylene ether backbone and / or a polytrimethylene ether backbone, (B) At least one photopolymerization initiator selected from benzophenone derivatives, methyl benzoate derivatives, and α-hydroxyacetophenone derivatives. (C) Fumed silica, (D) Reactive diluents with (meth)acryloyl groups, When the total amount of component (A) and component (D) is 100 parts by mass, the content of fumed silica (C) is 4 parts by mass or more. The surface viscosity of the cured film obtained by LED light curing at 365 nm in the presence of air was 20 gf / cm. 2 the following.

2. The active energy ray-curable resin composition as described in claim 1, characterized in that: The polytetramethylene ether skeleton of component (A) is polytetramethylene ether.

3. The active energy ray-curable resin composition as described in claim 1, characterized in that: The polyisocyanate skeleton of component (A) is derived from aliphatic polyisocyanates.

4. The active energy ray-curable resin composition as described in claim 1, characterized in that: The polyisocyanate skeleton of component (A) is derived from isophorone diisocyanate derivatives and / or 4,4'-methylene bis(cyclohexyl isocyanate) derivatives.

5. The active energy ray-curable resin composition as described in claim 1, characterized in that: When the total mass percentage of component (D) is 100%, it contains 10% to 100% of a reactive diluent having an SP value of 9.1 or less calculated by Fedors formula.

6. The active energy ray-curable resin composition according to claim 1, characterized in that: The (D) component, when the total (D) component is 100% by mass, contains 0% by mass and less than 10% by mass of a reactive diluent having a (meth)acryloyl group with an SP value of 9.1 or less calculated by Fedors formula, and the (C) component contains methacryloyl-modified fumed silica.

Images