JP2019218500A - Active energy ray-curable resin composition, coating agent using the same and sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To have excellent adhesion to a substrate, elongation and strength when cured, no surface tack feeling, excellent chemical resistance, excellent processability and productivity, and particularly for decorative molding. Provided are an active energy ray-curable resin composition and a coating agent using the same, and a sheet suitable for the present invention. SOLUTION: The active energy ray curable containing urethane (meth) acrylate (A) which is a reaction product of an alicyclic structure-containing polyisocyanate (a1), a polyol (a2), and a hydroxyl group-containing (meth) acrylate (a3). In the resin composition, the polyol (a2) comprises a low molecular weight polyol (a2-1) having a number average molecular weight of 60 to 300 and a high molecular weight polyester-based polyol (a2-2) having a number average molecular weight of 500 to 20,000. It is assumed that the urethane bond concentration of the urethane (meth) acrylate (A) is 3.5 mmol / g or more. [Selection diagram] None

Description

  The present invention relates to an active energy ray-curable resin composition, and more particularly, for example, when used as a cured coating film, is excellent in adhesion to a substrate, elongation of the coating film, elastic modulus and strength, and further has a surface tackiness. Active energy ray-curable resin composition having no chemical resistance, excellent chemical resistance, and excellent workability, especially an active energy ray-curable resin composition suitable for decorative molding applications, and a coating agent using the same , As well as sheets.

  BACKGROUND ART Plastic substrates such as polycarbonate and polymethyl methacrylate are widely used in home electric appliances, in-vehicle products, liquid crystal display members, etc. because of their excellent optical properties such as processability, impact resistance, and transparency.

  However, since the surface of these plastic substrates is easily damaged, the surface of the plastic substrate may be coated with a hard coat agent in order to impart abrasion resistance. As the hard coating agent, an active energy ray-curable resin composition is often used because of its excellent adhesion to a plastic substrate and its high curing speed which contributes to improvement in productivity.

Further, the active energy ray-curable resin composition may be used when performing decorative molding for imparting design properties.
Conventionally, as a method of decorative molding, there is a method in which a pigment is kneaded into a thermoplastic resin and molded, or a paint is spray-coated on the surface of the molded resin product to decorate. However, these techniques are difficult to apply to molded articles having complicated shapes.
Accordingly, the decorative molding is performed by three-dimensional molding such as insert molding or in-mold molding using a mold, and more recently, TOM molding (Three Dimension Overlay Method (three-dimensional surface coating method)) that does not require a mold. By doing so, application of decorative molding to a molded article having a complicated shape is being studied.

In the active energy ray-curable resin composition used in three-dimensional molding and the like as described above, in particular, workability such that cracks do not occur even when molded into a complicated shape, followability to a mold, and elongation. Degree is required.
Further, when the active energy ray-curable resin composition is used as the outermost surface material of a molded product, the surface hardness and scratch resistance are required. In particular, a molded product that may come into contact with the fingers is required to have, in addition to the characteristics described above, suppression of surface tackiness and chemical resistance to sunscreen, hand cream, and the like.

Here, for example, Patent Literature 1 below discloses a decorative molded sheet having a skin layer made of a reaction cured product of a resin composition containing a polycarbonate-based polyurethane and a non-yellowing polyisocyanate. Patent Document 1 discloses that a molded article using the decorative molded sheet has a complicated surface shape and is excellent in abrasion resistance.
Further, for example, Patent Literature 2 below discloses a method for producing a decorative sheet composition and a molded product comprising a compound containing a furyl group, a polymerizable compound, and a polymerization initiator. Patent Literature 2 discloses that a decorative sheet using the above composition achieves both high hard coatability and moldability, which are compatible with various molding processes, at a high level.

JP 2014-128922 A JP 2017-193694 A

However, the resin composition disclosed in Patent Document 1 contains a polyisocyanate as a thermosetting agent, and it is necessary to apply heat or provide an aging period in order to complete the curing of the coating film. Therefore, productivity is poor.
Further, the composition disclosed in Patent Document 2 has excellent hard coat properties and chemical resistance, but does not have elongation that can be used in various molding methods. Will remain.

  The present invention has been made in view of such circumstances, and when cured, has excellent adhesiveness to a substrate, elongation, elasticity and strength, has no surface tackiness, and has excellent chemical resistance. Provided are an active energy ray-curable resin composition which is excellent in processability and productivity and is particularly suitable for decorative molding applications, a coating agent using the same, and a sheet.

  The present inventors have intensively studied to solve the above-mentioned problems. In the course of the research, the use of urethane (meth) acrylate as a main component of the active energy ray-curable resin composition was examined. And, as a material of the urethane (meth) acrylate, an alicyclic structure-containing polyisocyanate is used for an isocyanate used in the urethane reaction, and a polyol used in the urethane reaction is a low molecular weight polyol having a number average molecular weight of 300 or less, A mixture of a high molecular weight polyester-based polyol having a molecular weight of 500 or more was used, and the urethane bond concentration of the urethane (meth) acrylate was adjusted to a specific range. As a result, they have found that the active energy ray-curable resin composition can form a cured coating film having excellent adhesion to a substrate, elongation, elastic modulus, and strength, and further having no surface tackiness.

That is, the present invention provides an active energy ray containing a urethane (meth) acrylate (A) which is a reaction product of an alicyclic structure-containing polyisocyanate (a1), a polyol (a2), and a hydroxyl group-containing (meth) acrylate (a3). A curable resin composition,
The polyol (a2) contains a low molecular weight polyol (a2-1) having a number average molecular weight of 60 to 300 and a high molecular weight polyester-based polyol (a2-2) having a number average molecular weight of 500 to 20,000,
An active energy ray-curable resin composition in which the urethane (meth) acrylate (A) has a urethane bond concentration of 3.5 mmol / g or more is referred to as a first gist.

  Further, a second aspect of the present invention provides a coating agent containing the active energy ray-curable resin composition. Further, a third aspect of the present invention is a sheet including a cured product of the active energy ray-curable resin composition.

As described above, the active energy ray-curable resin composition of the present invention comprises a urethane (meth) which is a reaction product of an alicyclic structure-containing polyisocyanate (a1), a polyol (a2), and a hydroxyl group-containing (meth) acrylate (a3). ) Acrylate (A). Then, as the polyol (a2), a low molecular weight polyol (a2-1) having a number average molecular weight of 60 to 300 and a high molecular weight polyester polyol (a2-2) having a number average molecular weight of 500 to 20,000 are used in combination, and the urethane is used. The urethane bond concentration of the (meth) acrylate (A) is 3.5 mmol / g or more. For this reason, the cured coating film formed by the active energy ray-curable resin composition of the present invention, and the cured coating film formed by the coating agent containing the active energy ray-curable resin composition of the present invention, It has excellent effects such as excellent adhesion to the substrate, elongation, elasticity and strength, no surface tackiness, excellent chemical resistance, excellent workability and productivity, and especially excellent in decorative molding applications.
Since the above-described effects are exhibited, the active energy ray-curable resin composition of the present invention can be used as a coating agent for various substrates, a sheet for molding, a material for a protective layer thereof, and a hard film for decorative film. Useful as a coating material.

  In particular, the ratio of the alicyclic structure-containing polyisocyanate (a1) is 30% by weight or more based on the total of the alicyclic structure-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3). In this case, it is possible to obtain a cured coating film having a higher elastic modulus.

  Further, based on the total of the alicyclic structure-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3), the alicyclic structure-containing polyisocyanate (a1) and the low molecular weight polyol (a2- When the total ratio of 1) is 40% by weight or more, the surface tackiness is further suppressed, and a cured coating film having excellent elastic modulus can be obtained.

  Furthermore, the ratio of the alicyclic structure-containing polyisocyanate (a1) is 30 to 60% by weight based on the total of the alicyclic structure-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3). %, The ratio of the low-molecular-weight polyol (a2-1) is 10 to 40% by weight, the ratio of the high-molecular-weight polyester-based polyol (a2-2) is 10 to 50% by weight, and the hydroxyl-containing ( When the proportion of the (meth) acrylate (a3) is 1 to 15% by weight, the surface tackiness is further suppressed, and a cured coating film having excellent elongation, elastic modulus and strength can be obtained.

  In addition, when the low-molecular-weight polyol (a2-1) has a branched structure, when a cured coating film is formed, association between urethane bonds is suppressed, and appropriate balance between crystallinity and flexibility is imparted. be able to.

  When the hydroxyl group-containing (meth) acrylate (a3) is a (meth) acrylate having one (meth) acryloyl group in the molecule, it imparts an appropriate cross-linked structure to the cured coating film and has an extensibility. Can be given.

  Next, embodiments of the present invention will be described in detail. However, the present invention is not limited to this embodiment.

  The active energy ray-curable resin composition (hereinafter sometimes abbreviated as “resin composition”) of the present invention is obtained using a specific urethane (meth) acrylate (A). The content of the urethane (meth) acrylate (A) in the resin composition (excluding the solvent) is usually at least 50% by weight, preferably at least 70% by weight, more preferably at least 90% by weight, It is more preferably at least 95% by weight. And in this invention, the case where the said resin composition consists only of the said urethane (meth) acrylate (A) except a solvent is also included. Hereinafter, details of the urethane (meth) acrylate (A) and each component material appropriately contained in the active energy ray-curable resin composition will be described.

<< Urethane (meth) acrylate (A) >>
The urethane (meth) acrylate (A) used in the present invention is a reaction product obtained by reacting an alicyclic structure-containing polyisocyanate (a1), a polyol (a2), and a hydroxyl group-containing (meth) acrylate (a3). Things. The polyol (a2) includes a low molecular weight polyol (a2-1) having a number average molecular weight of 60 to 300 and a high molecular weight polyester-based polyol (a2-2) having a number average molecular weight of 500 to 20,000.
That is, the urethane (meth) acrylate (A) used in the present invention has a structural unit derived from an alicyclic structure-containing polyisocyanate (a1), a structure derived from a low molecular weight polyol (a2-1) having a number average molecular weight of 60 to 300, and It is a compound having a unit, a structural unit derived from a high molecular weight polyester-based polyol (a2-2) having a number average molecular weight of 500 to 20,000, and a structural unit derived from a hydroxyl group-containing (meth) acrylate (a3).
From the viewpoint of the effects of the present invention, 50% by weight or more, particularly 80% by weight or more of the entire polyol (a2) is the low-molecular-weight polyol (a2-1) and the high-molecular-weight polyester-based polyol (a2-2). Preferably, all of the polyol (a2) comprises the low-molecular-weight polyol (a2-1) and the high-molecular-weight polyester-based polyol (a2-2).

The urethane bond concentration of the urethane (meth) acrylate (A) is 3.5 mmol / g or more. Preferably, the urethane bond concentration of the urethane (meth) acrylate (A) is 3.5 to 6 mmol / g, more preferably 4 to 5.5 mmol / g. The urethane bond concentration is a value obtained by calculating the ratio of urethane bonds [—NHC (（O) O—] in the urethane (meth) acrylate (A) from the composition of the urethane (meth) acrylate (A). is there. Specifically, the number of isocyanate functional groups of the alicyclic structure-containing polyisocyanate (a1) is N, the molar mass of the alicyclic structure-containing polyisocyanate (a1) is M (g / mol), and the alicyclic structure-containing polyisocyanate (a1) When the ratio of the alicyclic structure-containing polyisocyanate (a1) to the total of the polyol, the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3) is represented by P (% by weight), the urethane bond concentration is represented by the following formula: It can be obtained by (1).
(N × 1000 / M) × (P / 100) (1)
As described above, since the urethane bond concentration of the urethane (meth) acrylate (A) is high, a high elastic modulus is particularly given to the cured coating film formed by the active energy ray-curable resin composition of the present invention. Can be.

  In the present invention, (meth) acryl means acryl or methacryl, (meth) acryloyl means acryloyl or methacryloyl, and (meth) acrylate means acrylate or methacrylate.

[Alicyclic Structure-Containing Polyisocyanate (a1)]
Examples of the alicyclic structure-containing polyisocyanate (a1) include, for example, isophorone diisocyanate, norbornene diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, 1,4-bis (isocyanatomethyl) cyclohexane, hydrogenated diphenylmethane diisocyanate, and the like. Is raised.
These may be used alone or in combination of two or more.
Above all, from the viewpoint of elongation of the cured coating film, the alicyclic structure-containing polyisocyanate (a1) is preferably a diisocyanate. From the same viewpoint, isophorone diisocyanate, 1,4-bis (isocyanatomethyl) cyclohexane, and 1,3-bis (isocyanatomethyl) cyclohexane are more preferable, and 1,3-bis (isocyanatomethyl) is particularly preferable. Cyclohexane.

  In particular, the amount of the alicyclic ring is higher than the total amount of the alicyclic structure-containing polyisocyanate (a1), polyol (a2), and hydroxyl group-containing (meth) acrylate (a3), which are constituent materials of the urethane (meth) acrylate (A). When the proportion of the structure-containing polyisocyanate (a1) is 30% by weight or more, a cured coating film having more excellent elastic modulus can be obtained. The proportion of the alicyclic structure-containing polyisocyanate (a1) is preferably 30 to 60% by weight, more preferably 35 to 57% by weight, and further preferably 40 to 55% by weight.

[Polyol (a2)]
As described above, the polyol (a2) includes a low molecular weight polyol (a2-1) having a number average molecular weight of 60 to 300 and a high molecular weight polyester-based polyol (a2-2) having a number average molecular weight of 500 to 20,000. ) Are used in combination.

  The number average molecular weight of the low molecular weight polyol (a2-1) is preferably from 80 to 300, and more preferably from 100 to 200. The number average molecular weight of the high molecular weight polyester polyol (a2-2) is preferably from 500 to 10,000, more preferably from 600 to 3,000, and still more preferably from 700 to 2,200. By doing so, a higher elastic modulus and a higher elongation can be easily provided, and the physical properties can be finely adjusted.

  In the present invention, the number average molecular weight is a number average molecular weight calculated based on a hydroxyl value measured according to JIS K1557. Specifically, the hydroxyl value is measured, and is calculated as (56.1 × 1000 × valence) / hydroxyl value [mgKOH / g] by a terminal group quantification method. In the above formula, the valence is the number of hydroxyl groups in one molecule.

With respect to the total of the alicyclic structure-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3), which are constituent materials of the urethane (meth) acrylate (A), the low molecular weight polyol ( The ratio of a2-1) is preferably 10 to 40% by weight, more preferably 12 to 30% by weight, and still more preferably 14 to 25% by weight.
Further, based on the total of the alicyclic structure-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3), which are constituent materials of the urethane (meth) acrylate (A), The proportion of the polyester polyol (a2-2) is preferably from 10 to 50% by weight, more preferably from 15 to 45% by weight, and still more preferably from 20 to 40% by weight.
Furthermore, the alicyclic structure-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3), which are constituent materials of the urethane (meth) acrylate (A), are compared with the alicyclic ring. The total ratio of the structure-containing polyisocyanate (a1) and the low molecular weight polyol (a2-1) is preferably at least 40% by weight, more preferably 50 to 90% by weight, and still more preferably 55 to 80% by weight. By setting the content in such a range, the surface tackiness is suppressed, and a cured coating film having an excellent elastic modulus can be obtained.

  In particular, the ratio (a2-1 / a2-2) of the low-molecular-weight polyol (a2-1) to the high-molecular-weight polyester-based polyol (a2-2) is 20/80 to 80/20 by weight. However, it is preferable because a higher elastic modulus and a higher elongation can be easily imparted and physical properties can be finely adjusted. From the same viewpoint, the ratio (weight ratio) is more preferably (a2-1 / a2-2) = 22/78 to 70/30, and particularly preferably (a2-1 / a2-2) = 25. / 75 to 60/40.

Specific examples of the low molecular weight polyol (a2-1) include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, dimethylolpropane, neopentyl glycol, and 2,2-diethyl-1,3. -Propanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-tetramethylenediol, 1,3-tetramethylenediol, 2-methyl-1,3-trimethylenediol, 1,5 -Pentamethylenediol, 1,6-hexamethylenediol, 3-methyl-1,5-pentamethylenediol, 2,4-diethyl-1,5-pentamethylenediol, pentaerythritol diacrylate, 1,9-nonanediol , 2-Methyl-1,3-hexanediol , Aliphatic alcohols such as 2-methyl-1,8-octanediol, alicyclic diols such as 1,4-cyclohexanediol, cyclohexyl dimethanol and tricyclodecane dimethanol, bisphenols such as bisphenol A, xylitol And sugar alcohols such as sorbitol. These can be used alone or in combination of two or more.
Among these, those having a branched structure are preferable, and diols having an aliphatic chain having a branched structure are particularly preferable from the viewpoints of imparting appropriate crystallinity and flexibility in a cured coating film. Further, from the viewpoint of yellowing of the cured coating film, a compound having a structure containing no aromatic ring or unsaturated group is more preferable, and aliphatic diols are particularly preferable, and neopentyl glycol is more preferable.

  Examples of the high molecular weight polyester polyol (a2-2) include a condensation polymer of a polyhydric alcohol and a polycarboxylic acid; a ring-opening polymer of a cyclic ester (lactone); a polyhydric alcohol and a polycarboxylic acid. Examples of the reaction product include three kinds of components, an acid and a cyclic ester.

  Examples of the polyhydric alcohol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, 1,4-tetramethylene diol, 1,3-tetramethylene diol, and 2-methyl-1,3-trimethyl diol. Methylene diol, 1,5-pentamethylene diol, neopentyl glycol, 1,6-hexamethylene diol, 2-methyl-2,4-pentane diol, 3-methyl-1,5-pentamethylene diol, 2,4- Diethyl-1,5-pentamethylenediol, glycerin, trimethylolpropane, trimethylolethane, cyclohexanediols (such as 1,4-cyclohexanediol), tricyclodecane dimethanol, bisphenols (such as bisphenol A), sugar Alcohol ethers (xylitol and sorbitol), and the like.

  Examples of the polycarboxylic acid include aliphatic dicarboxylic acids such as malonic acid, maleic acid, fumaric acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and dodecandioic acid; -Alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid; aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, orthophthalic acid, 2,6-naphthalenedicarboxylic acid, paraphenylenedicarboxylic acid, and trimellitic acid.

  Examples of the cyclic ester include propiolactone, β-methyl-δ-valerolactone, ε-caprolactone, and the like.

  As the polyol (a2) as a whole, it is preferable to use a bifunctional polyol (having two hydroxyl groups) from the viewpoint that extensibility can be imparted when a cured coating film is formed. Further, a bifunctional polyol and a trifunctional polyol are used. A polyol (having three hydroxyl groups) may be used in combination.

[Hydroxy group-containing (meth) acrylate (a3)]
As the hydroxyl group-containing (meth) acrylate (a3), specifically, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl ( Hydroxyalkyl (meth) acrylate having an alkyl group of 1 to 16 (preferably 1 to 12) such as meth) acrylate and 6-hydroxyhexyl (meth) acrylate, 2-hydroxyethylacryloyl phosphate, 2- (meth) Acryloyloxyethyl-2-hydroxypropyl phthalate, caprolactone-modified 2-hydroxyethyl (meth) acrylate, dipropylene glycol (meth) acrylate, fatty acid-modified glycidyl (meth) acrylate, polyethylene glycol mono (meth ) Compounds having one (meth) acryloyl group such as acrylate, polypropylene glycol mono (meth) acrylate and 2-hydroxy-3- (meth) acryloyloxypropyl (meth) acrylate; glycerin di (meth) acrylate, 2- Compounds having two (meth) acryloyl groups such as hydroxy-3-acryloyl-oxypropyl methacrylate; pentaerythritol tri (meth) acrylate, caprolactone-modified pentaerythritol tri (meth) acrylate, ethylene oxide-modified pentaerythritol tri (meth) acrylate , Dipentaerythritol penta (meth) acrylate, caprolactone-modified dipentaerythritol penta (meth) acrylate, ethylene oxide-modified dipentaerythritol Penta (meth) acrylate, compounds having (meth) 3 or more acryloyl groups and succinic acid-modified pentaerythritol tri (meth) acrylate.
These may be used alone or in combination of two or more.

  Among these, a hydroxyl group-containing (meth) acrylate having one (meth) acryloyl group in the molecule is preferable because it can impart an appropriate cross-linked structure to the cured coating film and impart elongation, and more preferably. , Hydroxyalkyl (meth) acrylate, more preferably 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6 -Hydroxyhexyl (meth) acrylate and caprolactone-modified 2-hydroxyethyl (meth) acrylate, particularly preferably 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) in terms of excellent reactivity and versatility. Acrylate, 4-hydroxy Butyl (meth) acrylate, caprolactone-modified 2-hydroxyethyl (meth) acrylate.

  The hydroxyl group-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3), which are the constituent materials of the urethane (meth) acrylate (A), have a hydroxyl group-containing content. The proportion of the (meth) acrylate (a3) is preferably 1 to 15% by weight, more preferably 2 to 13% by weight, and still more preferably 2 to 10% by weight.

[Preparation of urethane (meth) acrylate (A)]
The urethane (meth) acrylate (A) used in the present invention includes, for example, the alicyclic structure-containing polyisocyanate (a1), low molecular weight polyol (a2-1), high molecular weight polyester-based polyol (a2-2), and hydroxyl group-containing. It can be produced by using (meth) acrylate (a3) and charging it into a reactor at once or separately and reacting it. The low molecular weight polyol (a2-1) and the high molecular weight polyester polyol (a2-2) The reaction product obtained by previously reacting the alicyclic structure-containing polyisocyanate (a1) with the hydroxyl group-containing (meth) acrylate (a3) can reduce the reaction stability and reduce by-products. Useful from the point of view.
In particular, after the alicyclic structure-containing polyisocyanate (a1) and the low molecular weight polyol (a2-1) are added and reacted in an organic solvent, the high molecular weight polyester-based polyol (a2-2) is further added and reacted. When the resultant reaction product is reacted with a hydroxyl group-containing (meth) acrylate (a3) to produce the desired urethane (meth) acrylate (A), the urethane (meth) acrylate (A) is favorably obtained. Can be manufactured.

  Then, in order to obtain the urethane (meth) acrylate (A) in good yield, an alicyclic structure-containing polyisocyanate (a1), a low molecular weight polyol (a2-1), a high molecular weight polyester-based polyol (a2-2), and a hydroxyl group-containing The molar ratio of the (meth) acrylate (a3) is preferably as follows.

  Known reaction means can be used for the reaction of the alicyclic structure-containing polyisocyanate (a1), low molecular weight polyol (a2-1), and high molecular weight polyester-based polyol (a2-2). At this time, for example, the isocyanate group in the alicyclic structure-containing polyisocyanate (a1) and the hydroxyl group in the polyol (the hydroxyl group in the low molecular weight polyol (a2-1) and the hydroxyl group in the high molecular weight polyester polyol (a2-2)) (Total) is usually about 2: 1 to 20:19 in terms of molar ratio of isocyanate group: hydroxyl group, whereby a terminal isocyanate group-containing urethane (meth) acrylate having an isocyanate group remaining can be obtained. Then, an addition reaction of the terminal isocyanate group with the hydroxyl group-containing (meth) acrylate (a3) becomes possible.

  A reaction product obtained by previously reacting the alicyclic structure-containing polyisocyanate (a1), the low-molecular-weight polyol (a2-1), and the high-molecular-weight polyester-based polyol (a2-2), and a hydroxyl group-containing (meth) Known reaction means can be used for the addition reaction with the acrylate (a3).

  The reaction molar ratio between the reaction product and the hydroxyl group-containing (meth) acrylate (a3) is, for example, such that the isocyanate group-containing polyisocyanate (a1) has two isocyanate groups and the hydroxyl group-containing (meth) acrylate (a3) has a hydroxyl group. Is one, the reaction product: hydroxyl group-containing (meth) acrylate (a3) is about 1: 2, the alicyclic structure-containing polyisocyanate (a1) has three isocyanate groups, and the hydroxyl group-containing ( When the number of hydroxyl groups of the (meth) acrylate (a3) is one, the ratio of reaction product: hydroxyl group-containing (meth) acrylate (a3) is about 1: 3.

  In the addition reaction between the reaction product and the hydroxyl group-containing (meth) acrylate (a3), the residual isocyanate group content of the reaction system is preferably 0.3% by weight or less, more preferably 0.1% by weight or less. By terminating the reaction at a certain point, unreacted components can be reduced, and urethane (meth) acrylate (A) can be obtained with good reproducibility.

  Regarding the reaction conditions, for example, the reaction temperature is preferably set in the range of about 30 to 80 ° C. in order to obtain urethane (meth) acrylate (A) with good yield, but the reaction heat can be controlled. Therefore, it is appropriate to carry out the reaction at 60 to 70 ° C., and the reaction time is usually 2 to 10 hours, preferably 3 to 8 hours.

Reaction of the alicyclic structure-containing polyisocyanate (a1), low-molecular-weight polyol (a2-1), and high-molecular-weight polyester-based polyol (a2-2), and the reaction product and a hydroxyl group-containing (meth) acrylate (a3) )), It is preferable to use a catalyst for the purpose of accelerating the reaction. Examples of the catalyst include dibutyltin dilaurate, dibutyltin diacetate, trimethyltin hydroxide, tetra-n-butyltin, and bisacetyl. Organometallic compounds such as zinc acetonate, zirconium tris (acetylacetonate) ethyl acetoacetate, zirconium tetraacetylacetonate, tin octenoate, zinc hexanoate, zinc octenoate, zinc stearate, zirconium 2-ethylhexanoate, naphthene Cobaltate, stannous chloride, Metal salts such as stannic chloride and potassium acetate, triethylamine, triethylenediamine, benzyldiethylamine, 1,4-diazabicyclo [2,2,2] octane, 1,8-diazabicyclo [5,4,0] -7-undecene , N, N, N ', N'-tetramethyl-1,3-butanediamine, amine catalysts such as N-methylmorpholine, N-ethylmorpholine, bismuth nitrate, bismuth bromide, bismuth iodide, bismuth sulfide, etc. Besides, organic bismuth compounds such as dibutyl bismuth dilaurate and dioctyl bismuth dilaurate, bismuth 2-ethylhexanoate, bismuth naphthenate, bismuth isodecanoate, bismuth neodecanoate, bismuth laurate, bismuth maleate, Bismuth stearate, bismuth oleate, linoleic acid Bismuth-based catalysts such as bismuth salts, bismuth acetate salts, bismuth livines neodecanoate, bismuth disalicylate salts, bismuth organic acid salts such as bismuth digallate salts and the like, among which dibutyltin dilaurate, 1,8- Diazabicyclo [5,4,0] -7-undecene is preferred.
These may be used alone or in combination of two or more.

  The amount of the catalyst is usually 5 to 1,000 ppm, preferably 10 to 500 ppm, more preferably 20 to 200 ppm, based on the total amount of the reaction components.

In the above reaction, it is preferable to further use a polymerization inhibitor. As the polymerization inhibitor, known general inhibitors used as polymerization inhibitors can be used. For example, p-benzoquinone, naphthoquinone, tolquinone, 2,5-diphenyl-p-benzoquinone, hydroquinone, 2,2 Quinones such as 5-di-t-butylhydroquinone, methylhydroquinone and mono-t-butylhydroquinone; aromatics such as 4-methoxyphenol and 2,6-di-tert-butylcresol; pt-butylcatechol And the like. Among them, aromatics are preferable, and 4-methoxyphenol and 2,6-di-tert-butylcresol are particularly preferable.
These may be used alone or in combination of two or more.

In the above reaction, as described above, it is preferable to use an organic solvent. Examples of the organic solvent include acetone, methyl isobutyl ketone, methyl ethyl ketone, ketones such as cyclohexanone, cellosolves such as ethyl cellosolve, aromatics such as toluene and xylene, and acetates such as methyl acetate, ethyl acetate and butyl acetate. And the like. These organic solvents may be used alone or in combination of two or more.
The content of the organic solvent in the active energy ray-curable resin composition of the present invention is usually 1 to 90% by weight, preferably 10 to 80% by weight, more preferably 20 to 70% by weight, and further preferably 30 to 70% by weight. ６０60% by weight. That is, if the content of the organic solvent is too small, there is a possibility that the handling property may be impaired due to extremely high viscosity, and if the content of the organic solvent is too large, the reaction rate is reduced and the productivity is adversely affected. This is because there is a fear.

  The number of ethylenically unsaturated groups contained in the urethane (meth) acrylate (A) is preferably 1 to 10, more preferably 1 to 6, and particularly preferably 1 to 3.

  The weight average molecular weight of the urethane (meth) acrylate (A) is preferably from 3,000 to 100,000, more preferably from 5,000 to 50,000, particularly preferably from 10,000 to 40,000, particularly preferably Is preferably 15,000 to 30,000. If the weight average molecular weight of the urethane (meth) acrylate (A) is too small, the concentration of ethylenically unsaturated groups in the cured coating film becomes relatively large, and the extensibility of the coating film is obtained when the cured coating film is formed. If the weight average molecular weight of the urethane (meth) acrylate (A) is too large, the viscosity tends to be high and the reaction control tends to be difficult, and the concentration of ethylenically unsaturated groups in the cured coating film tends to be low. Since the crosslinked density is relatively small and the crosslinked density is low, the elasticity of the cured coating film tends to be low although the extensibility of the cured coating film is obtained.

  The weight-average molecular weight is a weight-average molecular weight in terms of standard polystyrene molecular weight. A high-performance liquid chromatograph (“ACQUITY APC system” manufactured by Waters) has one column: ACQUITY APC XT 450, ACQUITY APC XT 200 And ACQUITY APC XT 45 are used in series.

The viscosity of the urethane (meth) acrylate (A) is adjusted by the content of the organic solvent described above, and is preferably 10 to 100,000 mPa · s at 20 ° C. It is more preferably from 100 to 50,000 mPa · s, and still more preferably from 1,000 to 25,000 mPa · s. If the viscosity is too low, the coatability tends to decrease, and if the viscosity is too high, handling becomes difficult or the coatability tends to decrease.
In addition, the said viscosity is measured using a B-type viscometer.

《Other materials》
The active energy ray-curable resin composition of the present invention preferably further contains a photopolymerization initiator in order to impart curability.

  The photopolymerization initiator is not particularly limited as long as it generates a radical by the action of light. For example, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl Ketal, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxy-cyclohexyl-phenyl-ketone, 1- [4- (2-hydroxyethoxy) -phenyl] -2- Hydroxy-2-methyl-1-propan-1-one, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl ) Butanone, 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone Benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether and benzoin isobutyl ether; benzophenone, methyl o-benzoyl benzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyl -Diphenyl sulfide, 3,3 ', 4,4'-tetra (t-butylperoxycarbonyl) benzophenone, 2,4,6-trimethylbenzophenone, 4-benzoyl-N, N-dimethyl-N- [2- ( 1-oxo-2-propenyloxy) ethyl] benzophenones such as benzenemethanaminium bromide and (4-benzoylbenzyl) trimethylammonium chloride; 2-isopropylthioxanthone, 4-isopropylthioxanthate , 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2- (3-dimethylamino-2-hydroxy) -3,4-dimethyl-9H-thioxanthone-9-one Thioxanthones such as mesochloride; 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide, bis (2,4 Acylphosphone oxides such as 6-trimethylbenzoyl) -phenylphosphine oxide; and the like. These photopolymerization initiators may be used alone or in combination of two or more.

  Further, as an auxiliary for the photopolymerization initiator, triethanolamine, triisopropanolamine, 4,4′-dimethylaminobenzophenone (Michler's ketone), 4,4′-diethylaminobenzophenone, 2-dimethylaminoethylbenzoic acid, Ethyl dimethylaminobenzoate, (n-butoxy) ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2,4-diethylthioxanthone, 2,4- It is also possible to use diisopropylthioxanthone or the like in combination. These auxiliaries may be used alone or in combination of two or more.

  The content of the photopolymerization initiator is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the specific urethane (meth) acrylate (A). Parts by weight, more preferably 1 to 7.5 parts by weight. If the content is too small, curing tends to be poor and a coating film tends to be hardly formed. If the content is too large, yellowing of the cured coating film tends to occur and coloring problems tend to occur.

  Further, in addition to the specific urethane (meth) acrylate (A) and the above-mentioned photopolymerization initiator, the active energy ray-curable resin composition of the present invention contains an antioxidant, a flame retardant, an antistatic agent, and a filler. , A leveling agent, a stabilizer, a reinforcing agent, a matting agent, and the like. Further, as the cross-linking agent, a compound having an action of causing cross-linking by heat, specifically, an epoxy compound, an azilysine compound, a melamine compound, an isocyanate compound, a chelate compound or the like can be used.

<< Active energy ray-curable resin composition >>
The active energy ray-curable resin composition of the present invention is produced by blending various additives such as a photopolymerization initiator in a predetermined blending amount with the specific urethane (meth) acrylate (A) and mixing. can do.

  The active energy ray-curable resin composition can be prepared by heating and mixing the above components at room temperature (25 ° C. ± 10 ° C.) or in a temperature range of room temperature to 60 ° C. in some cases. Preferably, the components other than the photopolymerization initiator are preliminarily mixed (0.5 to 30 hours) at room temperature or in a heated state in the above temperature range, and then mixed with the photopolymerization initiator to obtain the active energy. It is to prepare a line-curable resin composition.

The thus obtained active energy ray-curable resin composition preferably has a viscosity of 10 to 100,000 mPa · s at 20 ° C., more preferably 100 to 50,000 mPa · s, and Preferably, it is 1,000 to 25,000 mPa · s. If the viscosity is too low, the coatability tends to decrease, and if the viscosity is too high, handling becomes difficult or the coatability tends to decrease.
In addition, the said viscosity is measured using a B-type viscometer.

《Coating agent, sheet》
The active energy ray-curable resin composition of the present invention is used, for example, for a coating agent.

  Further, the active energy ray-curable resin composition can be used as a sheet, and after coating on a base material to form a coating film, the coating film is cured by irradiating with an active energy ray, and is peeled off. Thus, a sheet can be manufactured.

  In the present invention, the “sheet” conceptually includes a sheet and a film.

  Substrates on which the active energy ray-curable resin composition of the present invention is applied include polyolefin resins, polyester resins, polycarbonate resins, acrylic resins, acrylonitrile butadiene styrene copolymer (ABS), polystyrene Metals (aluminum, copper, etc.), such as plastic bases such as base resins and their molded products (films, sheets, cups, etc.), composite bases thereof, or composite bases of the above materials mixed with glass fibers and inorganic substances. Base materials such as iron, SUS, zinc, magnesium, and alloys thereof, and a base material provided with a primer layer on a base material such as glass.

  Examples of the method for applying the active energy ray-curable resin composition of the present invention include a wet coating method such as spraying, showering, dipping, roll, spinning, and screen printing. What is necessary is just to apply to a base material.

  Examples of active energy rays used for curing the active energy ray-curable resin composition applied on the substrate include far ultraviolet rays, ultraviolet rays, near ultraviolet rays, light rays such as infrared rays, X-rays, γ-rays and the like. In addition to the above electromagnetic waves, electron beams, proton beams, neutron beams and the like can be used, but curing by ultraviolet irradiation is advantageous from the viewpoints of curing speed, availability of an irradiation device, and price. When electron beam irradiation is performed, curing can be performed without using the above-mentioned photopolymerization initiator.

When curing the active energy ray-curable resin composition of the present invention by ultraviolet irradiation, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a xenon lamp, a chemical that emits light in a wavelength range of 150 to 450 nm is used. Irradiation with ultraviolet rays of usually 30 to 3,000 mJ / cm ² (preferably 100 to 1,500 mJ / cm ² ) may be performed using a lamp, an electrodeless discharge lamp, an LED, or the like.
After the ultraviolet irradiation, if necessary, heating may be performed to complete the curing. The heating conditions at that time include, for example, a temperature of 120 to 200 ° C.

  The coating thickness (thickness after curing) is usually 0.5 to 100 μm, and is preferably 0.5 to 100 μm, in consideration of light transmission so that the photopolymerization initiator reacts uniformly as an ultraviolet-curable coating film. Is 0.7 to 30 μm, more preferably 1 to 10 μm.

  After forming a coating film using an active energy ray-curable resin composition, when curing the same, if an organic solvent remains in the resin composition, the organic solvent is dried and then cured. Is preferred. The drying conditions are preferably at a temperature of 40 to 120 ° C for 1 to 20 minutes, more preferably at a temperature of 50 to 100 ° C for 2 to 10 minutes.

The active energy ray-curable resin composition of the present invention has high processability such that cracks do not occur even when molded into a complicated shape, high conformability to a mold, high elongation, and high adhesion to a substrate. Further, since it has no surface tackiness and excellent chemical resistance (resistance to sunscreen and hand cream, etc.), it is excellent as a material for forming a molded product that may come into contact with fingers. In particular, it is suitable for decorative molding.
Due to these characteristics, for example, a hard coat agent applied to the surface of a plastic part or the like, or a surface layer portion of a mobile phone such as a smartphone, an interior / exterior part for a vehicle, a sign pole, a barber apparatus, an amusement apparatus, or the like. And the like.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples as long as the gist is not exceeded.
In the examples, “parts” and “%” mean on a weight basis.
The weight average molecular weight, number average molecular weight, and viscosity were measured according to the methods described above.

[Example 1]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 250 g (1.29 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and neopentyl glycol (the present invention) (A2-1)) {molecular weight: 104} 120.7 g (1.16 mol), 500 g of ethyl acetate as a diluting solvent were charged and heated at 50 ° C. After dissolving neopentyl glycol (corresponding to (a2-1) of the present invention), 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 70 ° C. When the residual isocyanate group becomes 1.2% or less, bifunctional polyester polyol (corresponding to (a2-2) of the present invention) {Composition: adipic acid, isophthalic acid, 3-methyl-1,5-pentane Methylene diol, a hydroxyl value of 63 mgKOH / g, and a number average molecular weight of 1,780６114 g (0.06 mol) were added and reacted at 70 ° C. When the residual isocyanate group became 0.6% or less, the mixture was cooled to 60 ° C., and 15.0 g (0.13 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) was added as a polymerization inhibitor. , 6-di-tert-butylcresol (0.4 g) was further charged and reacted at 60 ° C., and the reaction was terminated when the residual isocyanate group became 0.1% or less, and the urethane acrylate compound (A-1) Was obtained (weight average molecular weight of A-1: 23,950, solution viscosity: 13,300 mPa · s / 20 ° C.).
To 100 parts of the urethane acrylate compound (A-1) in the above solution, 4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by IGM Resins, "Omnirad 184")) was further mixed. Thus, an active energy ray-curable resin composition was obtained.

[Example 2]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 218 g (1.12 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and neopentyl glycol (the present invention) (Corresponding to (a2-1)) {molecular weight: 104} 87.5 g (0.84 mol), 500 g of ethyl acetate as a diluting solvent were charged, and the mixture was heated at 50 ° C. After dissolving neopentyl glycol (corresponding to (a2-1) of the present invention), 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 70 ° C. When the remaining isocyanate groups become 2.9% or less, bifunctional polyester polyol (corresponding to (a2-2) of the present invention) {Composition: adipic acid, isophthalic acid, 1,6-hexamethylenediol, hydroxyl group A value of 121 mgKOH / g and a number average molecular weight of 927 to 173 g (0.19 mol) were added, and the mixture was reacted at 70 ° C. When the residual isocyanate group became 0.8% or less, the mixture was cooled to 60 ° C., and 21.7 g (0.19 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) was used as a polymerization inhibitor. , 6-di-tert-butylcresol (0.4 g) was further charged and reacted at 60 ° C., and the reaction was terminated when the residual isocyanate group became 0.1% or less, and the urethane acrylate compound (A-2) Was obtained (weight average molecular weight of A-2: 19,000, solution viscosity: 8,000 mPa · s / 20 ° C.).
To 100 parts of the urethane acrylate compound (A-2) in the above solution, 4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by IGM Resins, "Omnirad 184")) was further mixed. Thus, an active energy ray-curable resin composition was obtained.

[Example 3]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 203 g (1.04 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and neopentyl glycol (the present invention) (Corresponding to (a2-1)) {molecular weight: 104} 87 g (0.84 mol), 500 g of ethyl acetate as a diluting solvent were charged, and the mixture was heated at 50 ° C. After dissolving neopentyl glycol (corresponding to (a2-1) of the present invention), 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 70 ° C. When the remaining isocyanate groups become 2.2% or less, a bifunctional polyester polyol (corresponding to (a2-2) of the present invention) {Composition: adipic acid, isophthalic acid, 3-methyl-1,5-pentane Methylene diol, a hydroxyl value of 63 mgKOH / g, and a number average molecular weight of 1,780 to 185 g (0.10 mol) were added and reacted at 70 ° C. When the residual isocyanate group became 0.9% or less, the mixture was cooled to 60 ° C., and 24.6 g (0.21 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) was used as a polymerization inhibitor. , 6-di-tert-butylcresol (0.4 g) was further charged and reacted at 60 ° C. When the remaining isocyanate groups became 0.1% or less, the reaction was terminated, and the urethane acrylate compound (A-3) Was obtained (weight average molecular weight of A-3: 15,700, solution viscosity: 5,100 mPa · s / 20 ° C.).
To 100 parts of the urethane acrylate compound (A-3) in the above solution, 4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by IGM Resins, "Omnirad 184")) was further mixed. Thus, an active energy ray-curable resin composition was obtained.

[Example 4]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 216 g (1.11 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and neopentyl glycol (the present invention) (A2-1)) {molecular weight: 104} 96.7 g (0.93 mol), 500 g of ethyl acetate as a diluting solvent were charged and heated at 50 ° C. After dissolving neopentyl glycol (corresponding to (a2-1) of the present invention), 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 70 ° C. When the residual isocyanate group becomes 1.9% or less, bifunctional polyester polyol (corresponding to (a2-2) of the present invention) {Composition: adipic acid, isophthalic acid, 3-methyl-1,5-pentane Methylene diol, a hydroxyl value of 63 mgKOH / g, and a number average molecular weight of 1,780 to 165 g (0.09 mol) were added and reacted at 70 ° C. When the residual isocyanate group became 0.8% or less, the mixture was cooled to 60 ° C., and 21.9 g (0.19 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) was added as a polymerization inhibitor. , 6-di-tert-butylcresol (0.4 g) was further charged and reacted at 60 ° C. When the remaining isocyanate groups became 0.1% or less, the reaction was terminated, and the urethane acrylate compound (A-4) Was obtained (weight average molecular weight of A-4: 17,700, solution viscosity: 6,300 mPa · s / 20 ° C.).
To 100 parts of the urethane acrylate compound (A-4) in the above solution, 4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by IGM Resins, "Omnirad 184")) was further mixed. Thus, an active energy ray-curable resin composition was obtained.

[Example 5]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 236 g (1.21 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and neopentyl glycol (the present invention) (Corresponding to (a2-1)) {molecular weight: 104} 111 g (1.06 mol), 500 g of butyl acetate as a diluting solvent were charged, and the mixture was heated at 50 ° C. After dissolving neopentyl glycol (corresponding to (a2-1) of the present invention), 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 70 ° C. When the residual isocyanate group becomes 1.5% or less, bifunctional polyester polyol (corresponding to (a2-2) of the present invention) {Composition: adipic acid, isophthalic acid, 3-methyl-1,5-pentane Methylene diol, a hydroxyl value of 63 mgKOH / g, and a number average molecular weight of 1,780 to 136 g (0.08 mol) were added and reacted at 70 ° C. When the residual isocyanate group became 0.7% or less, the mixture was cooled to 60 ° C., and 17.6 g (0.15 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) was added as a polymerization inhibitor. , 6-di-tert-butylcresol (0.4 g) was further charged and reacted at 60 ° C. When the remaining isocyanate groups became 0.1% or less, the reaction was terminated and the urethane acrylate compound (A-5) Was obtained (weight average molecular weight of A-5: 22,400, solution viscosity: 20,900 mPa · s / 20 ° C.).
To 100 parts of the urethane acrylate compound (A-5) in the above solution, 4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone ("Omnirad 184", manufactured by IGM Resins)) was further mixed. Thus, an active energy ray-curable resin composition was obtained.

[Example 6]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 233 g (1.20 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and neopentyl glycol (the present invention) (A2-1)) {molecular weight: 104} 93.6 g (0.90 mol), 500 g of ethyl acetate as a diluting solvent were charged, and the mixture was heated at 50 ° C. After dissolving neopentyl glycol (corresponding to (a2-1) of the present invention), 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 70 ° C. When the residual isocyanate group becomes 3.1% or less, bifunctional polyester polyol (corresponding to (a2-2) of the present invention) {Composition: adipic acid, isophthalic acid, 1,6-hexamethylenediol, hydroxyl group A value of 121 mgKOH / g and a number average molecular weight of 927 to 139 g (0.15 mol) were added, and the mixture was reacted at 70 ° C. When the residual isocyanate group became 1.3% or less, the mixture was cooled to 60 ° C., and 34.8 g (0.30 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) was used as a polymerization inhibitor. , 6-di-tert-butylcresol (0.4 g) was further charged and reacted at 60 ° C. When the remaining isocyanate groups became 0.1% or less, the reaction was terminated, and the urethane acrylate compound (A-6) Was obtained (weight average molecular weight of A-6: 10,940, solution viscosity: 2,200 mPa · s / 20 ° C.).
To 100 parts of the urethane acrylate compound (A-6) in the above solution, 4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone (“Omnirad 184”, manufactured by IGM Resins)) was further mixed. Thus, an active energy ray-curable resin composition was obtained.

[Comparative Example 1]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 181 g (0.93 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and neopentyl glycol (the present invention) (A2-1)) Molecular weight: 104 48.7 g (0.47 mol), 300 g of butyl acetate as a diluting solvent were charged, and the mixture was heated at 50 ° C. After dissolving neopentyl glycol (corresponding to (a2-1) of the present invention), 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 70 ° C. When the residual isocyanate group becomes 7.4% or less, bifunctional polyester polyol (corresponding to (a2-2) of the present invention) {Composition: adipic acid, isophthalic acid, 3-methyl-1,5-pentane Methylene diol, a hydroxyl value of 63 mgKOH / g, and a number average molecular weight of 1,780 to 415 g (0.23 mol) were added and reacted at 70 ° C. When the residual isocyanate group became 2.1% or less, the mixture was cooled to 60 ° C., and 55.1 g (0.47 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) was added as a polymerization inhibitor. , 6-di-tert-butylcresol (0.4 g) was further charged and reacted at 60 ° C. When the remaining isocyanate groups became 0.1% or less, the reaction was terminated and the urethane acrylate compound (A′-1) )) (Weight average molecular weight of A′-1: 13,200, solution viscosity: 7,000 mPa · s / 20 ° C.).
4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by IGM Resins, "Omnirad 184")) is further mixed with 100 parts of the urethane acrylate compound (A'-1) in the above solution. Thus, an active energy ray-curable resin composition was obtained.

[Comparative Example 2]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 227 g (1.17 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and neopentyl glycol (the present invention) (A2-1)) {molecular weight: 104} 81.2 g (0.78 mol), 300 g of ethyl acetate as a diluting solvent were charged, and the mixture was heated at 50 ° C. After dissolving neopentyl glycol (corresponding to (a2-1) of the present invention), 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 70 ° C. When the residual isocyanate group becomes 5.4% or less, bifunctional polyester polyol (corresponding to (a2-2) of the present invention) {Composition: adipic acid, isophthalic acid, 3-methyl-1,5-pentane Methylene diol, a hydroxyl value of 63 mgKOH / g, and a number average molecular weight of 1,780 to 346 g (0.19 mol) were added, and the mixture was reacted at 70 ° C. When the residual isocyanate group became 1.7% or less, the mixture was cooled to 60 ° C., and 45.9 g (0.40 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) was used as a polymerization inhibitor. , 6-di-tert-butylcresol (0.4 g) was further charged and reacted at 60 ° C., and when the remaining isocyanate groups became 0.1% or less, the reaction was terminated and the urethane acrylate compound (A′-2) ) Was obtained (weight average molecular weight of A'-2: 13,300, solution viscosity: 9,000 mPa · s / 20 ° C.).
To 100 parts of the urethane acrylate compound (A'-2) in the above solution, 4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by IGM Resins, "Omnilad 184")) was further mixed. Thus, an active energy ray-curable resin composition was obtained.

[Comparative Example 3]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 162 g (0.84 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and a bifunctional polyester polyol ( (Corresponding to (a2-2) of the present invention) Composition: adipic acid, isophthalic acid, 3-methyl-1,5-pentamethylenediol, hydroxyl value 63 mgKOH / g, number average molecular weight 1,780１，739 g (0.42 Mol), and 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 60 ° C. When the residual isocyanate groups become 3.9% or less, 98.4 g (0.85 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) and 2,6-di- 0.4 g of tert-butylcresol was further charged and reacted at 60 ° C., and when the remaining isocyanate groups became 0.1% or less, the reaction was terminated to obtain a urethane acrylate compound (A′-3) ( A'-3 weight average molecular weight: 10,000, viscosity: 50,000 mPa · s / 60 ° C).
4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by IGM Resins, "Omnirad 184")) is further mixed with 100 parts of the urethane acrylate compound (A'-3) in the above solution. Thus, an active energy ray-curable resin composition was obtained.

[Comparative Example 4]
In a flask equipped with an internal thermometer, a stirrer, and a condenser, 418 g (2.15 mol) of 1,3-bis (isocyanatomethyl) cyclohexane (corresponding to (a1) of the present invention) and neopentyl glycol (the present invention) 179 g (1.72 mol) of molecular weight: 104, and 300 g of ethyl acetate as a diluting solvent were charged and heated at 70 ° C. After dissolving neopentyl glycol (corresponding to (a2-1) of the present invention), 0.1 g of dibutyltin dilaurate was added as a reaction catalyst and reacted at 70 ° C. When the residual isocyanate group became 4.0% or less, the mixture was cooled to 60 ° C., and 102 g (0.88 mol) of 2-hydroxyethyl acrylate (corresponding to (a3) of the present invention) was used. Further, 0.4 g of -di-tert-butylcresol was charged and reacted at 60 ° C. When the remaining isocyanate groups became 0.1% or less, the reaction was terminated, and the urethane acrylate compound (A'-4) A 30% solution of ethyl acetate was obtained (weight average molecular weight of A'-4: 3,900, solution viscosity: 10,000 mPa · s / 20 ° C.).
4 parts of a photopolymerization initiator (1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by IGM Resins, "Omnirad 184")) is further mixed with 100 parts of the urethane acrylate compound (A'-4) in the solution. Thus, an active energy ray-curable resin composition was obtained.

  Using the active energy ray-curable resin composition thus obtained, a sample for evaluation was prepared as described below, and the sample was evaluated for elongation, elastic modulus, strength, surface tack evaluation, and chemical resistance. Was evaluated as follows. The results are shown in Table 1 below. Table 1 below shows the material composition (%) of urethane acrylate compounds (A-1 to A-6, A'-1 to A'-4), which are components of the active energy ray-curable resin composition. (Use ratio of each material corresponding to each of a1, a2-1, a2-2, and a3 of the present invention), and the composition of the urethane acrylate compound, the urethane bond in the urethane acrylate compound [-NHC (= The value (urethane bond concentration (mmol / g)) of the ratio of O) O-] calculated according to the above formula (1) is also shown.

[Preparation of evaluation sample]
The active energy ray-curable resin composition is applied to a release polyethylene terephthalate (PET) film with an applicator, dried at 60 ° C. for 30 minutes with a drier, and then exposed to 18 cm of high pressure mercury lamp (80 W). At a conveyor speed of 3.4 m / min from the height of the substrate, irradiation of ultraviolet rays (integrated irradiation amount: 800 mJ / cm ² ) was performed to obtain a cured coating film (film thickness: 100 μm). Next, the cured coating film was punched out with a dumbbell to prepare a strip-shaped sample having a width of 15 mm and a length of 75 mm, and then the cured coating film was peeled off from the PET film to obtain a sample piece for evaluation.

<Elongation>
Using a tensile tester “AG-X” (manufactured by Shimadzu Corporation), the sample was subjected to a tensile test at a temperature of 23 ° C. and a humidity of 50% in accordance with JIS K 7127. The elongation at the breaking point of the coating film was measured at a tensile speed of 10 mm / min and evaluated according to the following criteria.
A: 200% or more.
・ ・ ・: 100% or more and less than 200%.
X: Less than 100%.

<Elastic modulus>
Using a tensile tester “AG-X” (manufactured by Shimadzu Corporation), the sample was subjected to a tensile test at a temperature of 23 ° C. and a humidity of 50% in accordance with JIS K 7127. The tensile speed was 10 mm / min, and the elastic modulus was measured in the range of 1% to 2% of the displacement of the stretching deformation of the coating film, and evaluated according to the following criteria.
・ ・ ・: 20 (N / mm ² ) or more.
・ ・ ・: 10 (N / mm ² ) or more and less than 20 (N / mm ² ).
×: Less than 10 (N / mm ² ).

<Strength>
Using a tensile tester “AG-X” (manufactured by Shimadzu Corporation), the sample was subjected to a tensile test at a temperature of 23 ° C. and a humidity of 50% in accordance with JIS K 7127. The tensile speed was 10 mm / min, and the strength at the breaking point of the coating film was measured and evaluated according to the following criteria.
◎: 15 (N / mm ² ) or more.
・ ・ ・: 5 (N / mm ² ) or more and less than 15 (N / mm ² ).
×: Less than 5 (N / mm ² ).

<Surface tack evaluation>
The presence or absence of tack on the surface of the sample was evaluated by finger touch according to the following criteria.
・ ・ ・: No tack is felt.
・ ・ ・: When the finger is pressed strongly, a slight tack is felt.
×: Tack is felt when a finger is pressed.

<Chemical resistance (i)>
Wes containing ethanol (manufactured by Nippon Paper Crecia Co., Ltd., "Kimwipe") with a weight of 500 g was pressed against the surface of the sample, and reciprocated 10 times in this state. Thereafter, the state of the sample surface was visually evaluated according to the following criteria.
・ ・ ・: There is no change on the sample surface.
Δ: The sample surface is slightly cloudy or scratched.
X: The sample surface is cloudy.

<Chemical resistance (ii)>
0.02 g / cm ² of a sunscreen (manufactured by Johnson & Johnson, “Neutrogena SPF45”) was applied to the surface of the sample, wiped off after standing at 40 ° C. for 1 hour, and the state of the sample surface was visually evaluated.
・ ・ ・: There is no change on the sample surface.
Δ: The coating film surface is slightly cloudy or scratched.
X: The coating film surface is clouded.

  From the above results, in all of the examples, the elongation, the elastic modulus, and the strength were all high, and further, high evaluation was obtained in the surface tack evaluation and the chemical resistance.

  On the other hand, the active energy ray-curable resin compositions of Comparative Examples 1 to 3 have a low urethane bond concentration of the urethane acrylate compound, and have an effect on the elastic modulus of the cured body of the resin composition. The results were inferior in surface tack evaluation and chemical resistance to sunscreen. In addition, the cured coating film of the active energy ray-curable resin composition of Comparative Example 4 was inferior in elongation and chemical resistance to ethanol.

The active energy ray-curable resin composition of the present invention has high processability such that cracks do not occur even when molded into a complicated shape, high conformability to a mold, high elongation, and high adhesion to a substrate. Further, since it has no surface tackiness and excellent chemical resistance (resistance to sunscreen and hand cream, etc.), it is excellent as a material for forming a molded product that may come into contact with fingers. In particular, it is suitable for decorative molding.
Due to these characteristics, for example, a hard coat agent applied to the surface of a plastic part or the like, or a surface layer portion of a mobile phone such as a smartphone, an interior / exterior part for a vehicle, a sign pole, a barber apparatus, an amusement apparatus, or the like. And the like. In addition, it can also be used for other applications utilizing the above characteristics.

Claims (8)

An active energy ray-curable resin composition containing a urethane (meth) acrylate (A) which is a reaction product of an alicyclic structure-containing polyisocyanate (a1), a polyol (a2), and a hydroxyl group-containing (meth) acrylate (a3). So,
The polyol (a2) contains a low molecular weight polyol (a2-1) having a number average molecular weight of 60 to 300 and a high molecular weight polyester-based polyol (a2-2) having a number average molecular weight of 500 to 20,000,
An active energy ray-curable resin composition, wherein the urethane (meth) acrylate (A) has a urethane bond concentration of 3.5 mmol / g or more.   The proportion of the alicyclic structure-containing polyisocyanate (a1) is 30% by weight or more based on the total of the alicyclic structure-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3). The active energy ray-curable resin composition according to claim 1, wherein:   Based on the total of the alicyclic structure-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3), the alicyclic structure-containing polyisocyanate (a1) and the low molecular weight polyol (a2-1) The active energy ray-curable resin composition according to claim 1 or 2, wherein a total ratio of the resin is 40% by weight or more.   The ratio of the alicyclic structure-containing polyisocyanate (a1) is 30 to 60% by weight based on the total of the alicyclic structure-containing polyisocyanate (a1), the polyol (a2), and the hydroxyl group-containing (meth) acrylate (a3). The ratio of the low-molecular-weight polyol (a2-1) is 10 to 40% by weight, the ratio of the high-molecular-weight polyester-based polyol (a2-2) is 10 to 50% by weight, and the hydroxyl-containing (meth) The active energy ray-curable resin composition according to any one of claims 1 to 3, wherein the proportion of the acrylate (a3) is 1 to 15% by weight.   The active energy ray-curable resin composition according to any one of claims 1 to 4, wherein the low molecular weight polyol (a2-1) has a branched structure.   The active energy according to any one of claims 1 to 5, wherein the hydroxyl group-containing (meth) acrylate (a3) is a (meth) acrylate having one (meth) acryloyl group in a molecule. A line-curable resin composition.   A coating agent comprising the active energy ray-curable resin composition according to claim 1.   A sheet comprising a cured product of the active energy ray-curable resin composition according to claim 1.