JP6903941B2 - Urethane (meth) acrylate oligomer - Google Patents

Description

The present invention is excellent in scratch resistance, elastic modulus, weather resistance, chemical resistance, etc. after curing, and is also excellent in stretchability after curing to follow the deformation of three-dimensional processing. Urethane (meth) acrylate. The present invention relates to an oligomer and a curable composition using the same. The present invention also relates to a cured product, a laminate, and a cured film using the urethane (meth) acrylate oligomer and the curable composition.

The radical polymerization type curable composition is cured in a short time by irradiation with active energy rays, and has excellent chemical resistance, stain resistance, scratch resistance, abrasion resistance, weather resistance, heat resistance, etc. Since it is possible to provide a molded product, it is widely used in various surface processing fields and cast molded product applications. Among such curable compositions, from the viewpoint of curability and work efficiency, a curable composition containing a urethane (meth) acrylate oligomer is previously cured by an active energy ray to produce a cured product, and the cured product is used. A method is used in which three-dimensional processing is performed at room temperature or under heating conditions after surface processing or the like. In this case, the cured product has stretchability after curing to follow the deformation during three-dimensional processing. You will need it.

Patent Document 1 describes at least one selected from diisocyanate compounds, polyether diols, polyester diols, and polycarbonate diols as having excellent transparency, low curing shrinkage, light transmittance, recording film protection performance, and low viscosity. A curable composition of a urethane (meth) acrylate oligomer which is a reaction product of one kind of diol compound, an epoxy di (meth) acrylate compound, and a hydroxy group-containing (meth) acrylic acid ester is disclosed.

Patent Document 2 describes diisocyanate compounds, compounds having two hydroxyl groups in the molecule and a molecular weight of 50 to 500, and diepoxy compounds having a cyclic skeleton in the molecule, as those having excellent surface hardness and moldability. A curable composition of a urethane (meth) acrylate oligomer, which is a reaction product of an epoxy (meth) acrylate having two hydroxyl groups in the molecule, synthesized from a (meth) acrylic acid derivative is disclosed.

Patent Document 3 states that the cured film has excellent curability, flexibility, and elongation, and is a bifunctional compound containing a polyisocyanate, a polycarbonate diol, and two hydroxyl groups and two ethylenically unsaturated groups in the molecule. A curable composition of a urethane (meth) acrylate oligomer which is a reaction product of an epoxy (meth) acrylate is disclosed.

Patent Document 4 describes polyisocyanate having an alicyclic structure and a chain fat having 8 to 16 carbon atoms as having stretchability and excellent coating appearance, scratch resistance, stain resistance, and abrasion resistance. A curable composition of a group diol and a urethane (meth) acrylate oligomer which is a reaction product of a hydroxyalkyl (meth) acrylate is disclosed.

Patent Document 5 contains a polymer which is a reaction product obtained by adding α, β-unsaturated monocarboxylic acid to a glycidyl (meth) acrylate-based polymer, a polyfunctional isocyanate, and an ultraviolet absorber as active ingredients. Although a curable resin composition comprising a thermosetting reaction product of an active energy ray-curable resin composition is disclosed, UV curing and thermosetting are indispensable for this curable composition. Further, since the UV curable resin and the thermosetting resin exist independently, there is a problem that the process becomes complicated. Further, Patent Document 5 only improves the weather resistance by improving the cracks in the cured film due to UV curing. Further, Patent Document 5 requires that the ultraviolet absorbing unit has an ester bond. The ester bond is a unit introduced to improve the solubility with a general-purpose resin, but it becomes a factor of lowering chemical resistance and light resistance.

Japanese Unexamined Patent Publication No. 2004-35715 Japanese Unexamined Patent Publication No. 2010-275339 Japanese Unexamined Patent Publication No. 2008-127475 Japanese Unexamined Patent Publication No. 2014-214270 Japanese Unexamined Patent Publication No. 2000-109652

According to a detailed study by the present inventors, the curable compositions described in Patent Documents 1 to 5 have scratch resistance, elastic modulus, weather resistance, chemical resistance, and deformation in three-dimensional processing. A problem has been found in which one of the stretchability after curing is insufficient to follow up. That is, the subject of the present invention is urethane (meth) which is excellent in scratch resistance, elastic modulus, weather resistance, chemical resistance, etc., and also excellent in stretchability after curing to follow the deformation of three-dimensional processing. It is an object of the present invention to provide an acrylate oligomer, and a curable composition, a cured product, a laminate, and a cured film using the same.

As a result of diligent studies to solve the above problems, the present inventors include a urethane (meth) acrylate oligomer having a specific chemical structure obtained by using a specific raw material, and an organic solvent thereof. We have found that a curable composition can solve the above-mentioned problems, and have arrived at the present invention. Here, the present invention has succeeded in simplifying the process by converting the ultraviolet absorbing unit into urethane (meth) acrylate to have ultraviolet curability. Further, the above-mentioned Patent Document 5 does not attempt to improve the three-dimensional followability as in the present invention. Further, in the present invention, since it is urethane (meth) acrylated, an ester bond is not essential for the ultraviolet absorbing unit as in Patent Document 5. That is, the curable composition containing the compound used in the present invention, which does not have an ester bond, has further improved chemical resistance and light resistance.
That is, the gist of the present invention lies in the following [1] to [12].

[1] A urethane (meth) acrylate oligomer having a chemical structure represented by the following formula (1) and a chemical structure represented by the following formula (2).

(In formula (1), X ¹ is an aliphatic structure having a molecular weight of 500 or less, and n is an integer of 2 to 8.)

[2] The urethane (meth) acrylate oligomer according to [1], which has a weight average molecular weight (Mw) of 1,500 to 30,000.

[3] The structural unit derived from the compound (C) represented by the following formula (3) is 0.05 to 50 weight by weight with respect to the structural unit derived from all the polyol components used as the raw material of the urethane (meth) acrylate oligomer. The urethane (meth) acrylate oligomer according to [1] or [2], which contains%.

[4] A urethane (meth) acrylate oligomer in which the following compound (A), the following compound (B), and the following compound (C) are reacted to obtain a urethane prepolymer, and then the following compound (D) is reacted with the urethane (meth) acrylate oligomer. Production method.
Compound (A): Polyisocyanate compound (B): Aliphatic polyol compound (C) having a molecular weight of 500 or less: Polyol represented by the above formula (3)

Compound (D): Compound having a hydroxyl group and a (meth) acryloyl group

[5] Production of the urethane (meth) acrylate oligomer according to [4], wherein the compound (C) is used in an amount of 0.05 to 50% by weight based on the total polyol component used as a raw material of the urethane (meth) acrylate oligomer. Method.

[6] A curable composition containing the urethane (meth) acrylate oligomer according to any one of [1] to [3] and an organic solvent.

[7] The curable composition according to [6], wherein the solubility parameter of the organic solvent is 8.0 to 11.5.

[8] The curable composition according to [6] or [7], which has a solid content concentration of 5 to 90% by weight.

[9] A cured product obtained by curing the curable composition according to any one of [6] to [8].

[10] A laminate having a cured product of the curable composition according to any one of [6] to [8] on a substrate.

[11] A cured film obtained by stretching the cured product according to [9].

[12] A step of applying the urethane (meth) acrylate oligomer according to any one of [1] to [3] or the curable composition according to any one of [6] to [8] onto a substrate. A method for producing a cured film, which comprises a step of irradiating a curable composition with active energy rays to obtain a cured product and a step of stretching the cured product.

According to the present invention, it is excellent in weather resistance after curing, coating film appearance, stain resistance, scratch resistance, abrasion resistance, chemical resistance, etc., particularly scratch resistance, elastic modulus, weather resistance, chemical resistance, etc. Further, a urethane (meth) acrylate oligomer having excellent stretchability after curing for following the deformation of three-dimensional processing and a curable composition using the same are provided. Further, according to the present invention, a cured product, a laminate, and a cured film using the urethane (meth) acrylate oligomer or the curable composition are provided.

Hereinafter, embodiments of the present invention will be described in detail, but the following description is typical examples of embodiments of the present invention, and the present invention is not limited to these contents. In the present invention, "(meth) acrylate" is a general term for acrylate and methacrylate, and means one or both of acrylate and methacrylate. Regarding "(meth) acryloyl" and "(meth) acrylic" Is the same. Further, in the present invention, "~" is used to mean that the numerical values described before and after the value are included as the lower limit value and the upper limit value.

[Urethane (meth) acrylate oligomer]
The urethane (meth) acrylate oligomer of the present invention has a chemical structure represented by the following formula (1) and a chemical structure represented by the following formula (2).

(In formula (1), X ¹ is an aliphatic structure having a molecular weight of 500 or less, and n is an integer of 2 to 8.)

The urethane (meth) acrylate oligomer of the present invention and the curable composition of the present invention described later have a coating film appearance after curing, weather resistance, stain resistance, scratch resistance, abrasion resistance, chemical resistance, etc., particularly scratch resistance. It is excellent in adhesiveness, elastic modulus, weather resistance, and chemical resistance, and also excellent in stretchability after curing to follow the deformation of three-dimensional processing. In particular, the balance between weather resistance, abrasion resistance, stain resistance, elastic modulus, scratch resistance, and chemical resistance is remarkably superior to the curable compositions described in Patent Documents 1 to 5. It is a thing.

The reason why the curable composition of the present invention exerts the above-mentioned excellent effects is not clear, but it is considered that the stain resistance, abrasion resistance and elastic modulus are due to the following reasons. That is, the urethane of the present invention (meth) acrylate oligomer, by having X ¹ of the chemical structure of the formula (1), a urethane bond distance between intramolecular becomes shorter, strongly from urethane linkages between molecules It is considered that this is due to the formation of various hydrogen bonds and the hardness and rigidity of the cured film. Since the urethane (meth) acrylate oligomers described in Patent Documents 1 to 3 use high molecular weight diols having a long chain length, hydrogen bonds are formed but the amount of urethane bonds is low, so that the obtained cured film can be obtained. It is presumed that the hardness and rigidity are insufficient, and the stain resistance and abrasion resistance are insufficient.

The weather resistance is derived from the chemical structure having an ultraviolet absorbing ability represented by the formula (2), and the weather resistance can be maintained for a long period of time by incorporating this chemical structure into the molecular chain. It is estimated to be. Since Patent Documents 1 to 4 do not have the chemical structure represented by the formula (2), it is presumed that the weather resistance is inferior to that of the urethane (meth) acrylate of the present invention.

Further, regarding chemical resistance, the compound described in Patent Document 5 requires an ester bond with respect to the ultraviolet absorbing unit. Therefore, it is presumed that this structure has some influence on the chemical resistance, but the urethane (meth) acrylate of the present invention does not have such a structure and is excellent in chemical resistance.

In the urethane (meth) acrylate of the present invention, the chemical structure represented by the formula (1) (hereinafter, may be referred to as “chemical structure (1)”) is usually compound (A) as described below. Is formed by the reaction of the polyisocyanate of compound (B) with an aliphatic polyol having a molecular weight of 500 or less. Further, in the urethane (meth) acrylate of the present invention, the chemical structure represented by the formula (2) (hereinafter, may be referred to as “chemical structure (2)”) is usually different from the above compound (A). It is formed by reacting the product obtained by the reaction with the compound (B) with the polyol represented by the formula (3). Further, by reacting the obtained reactant with a compound having a hydroxyl group of compound (D) and a (meth) acryloyl group, a (meth) acryloyl group is introduced at the terminal, and the urethane (meth) acrylate of the present invention is introduced. Can be obtained.
That is, the chemical structure of the urethane (meth) acrylate of the present invention is the chemical structure derived from the (meth) acryloyl group in order from the end of the main chain, and the internal structure thereof is the chemical structure represented by the formula (1). , A compound having at least a chemical structure represented by the formula (2) and having a structure in which these are bonded in a random order.

In the formula (1), X ¹ is not particularly limited as long as it has an aliphatic structure having a molecular weight of 500 or less, but is preferably an aliphatic structure having a molecular weight of 400 or less, and more preferably an aliphatic structure having a molecular weight of 300 or less. .. On the other hand, X ¹ preferably has an aliphatic structure having a molecular weight of 14 or more, and more preferably 28 or more. X ¹ corresponds to a residue having a hydroxyl group bonded to the aliphatic structure of compound (B) described later, and is a fat regardless of whether it is a linear aliphatic structure or a branched chain aliphatic structure. It may have a ring structure.

In the formula (1), n is an integer of 2 to 8, but n is preferably 2 to 6, and more preferably 2 to 4. Specifically, when the value of n is 2, the chemical structure represented by the formula (1) is the following formula (1-1), and when the value of n is 3, the formula (1) The chemical structure represented by is given by the following formula (1-2).

(In equations (1-1) and (1-2), X ¹ is synonymous with that in equation (1).)

The urethane (meth) acrylate oligomer of the present invention may have a chemical structure (1) and a chemical structure (2), and has a chemical structure (1) and a chemical structure as long as the effects of the present invention are not significantly impaired. It may have a chemical structure other than (2). Other chemical structures include chemical structures derived from other raw material compounds described below.

The urethane (meth) acrylate oligomer of the present invention has a chemical structure (1) of urethane (meth) in order to surely obtain the hardness and rigidity of the cured film derived from the high urethane bond amount based on the chemical structure (1). The acrylate oligomer preferably contains 5% by weight or more, and particularly preferably 10% by weight or more.
Further, in order to surely obtain excellent weather resistance based on the chemical structure (2), the chemical structure (2) is contained in the urethane (meth) acrylate oligomer in an amount of 0.1% by weight or more, particularly 0.5% by weight or more. Is preferable.
In order to obtain the effect of the chemical structure (1) and the effect of the chemical structure (2) in a well-balanced manner, the urethane (meth) acrylate oligomer of the present invention has a chemical structure (1) of 10 to 50 in the urethane (meth) acrylate oligomer. It is preferably contained in an amount of 0.5 to 30% by weight of the chemical structure (2).

Urethane (meth) acrylate oligomer of the present invention may be one having a chemical structure corresponding to the chemical structure (1) alone, having two or more of X ¹ and n is different from the chemical structure (1) It may be a thing.

[Weight average molecular weight (Mw)]
The weight average molecular weight (Mw) of the urethane (meth) acrylate oligomer is preferably 1,500 or more, more preferably 3,000 or more, while it is preferably 30,000 or less, preferably 25,000. It is more preferably less than or equal to 20,000 or less. When the weight average molecular weight of the urethane (meth) acrylate oligomer is at least the above lower limit value, the three-dimensional processability of the obtained cured film tends to be good. When the number average molecular weight of the urethane (meth) acrylate oligomer is not more than the above upper limit value, the stain resistance of the cured film obtained from the curable composition tends to be good. The weight average molecular weight of the urethane (meth) acrylate oligomer is related to the distance between the cross-linking points in the network structure of the urethane (meth) acrylate oligomer, and the three-dimensional processability and stain resistance of the cured film obtained by using the distance. The smaller the weight average molecular weight, the shorter the distance between the cross-linking points, and the larger the weight average molecular weight, the longer the distance between the cross-linking points. The reason why the weight average molecular weight affects the three-dimensional workability and stain resistance is that the elastic modulus decreases as the distance between the cross-linking points increases, the structure becomes flexible and stretchable, and the three-dimensional workability becomes better, while this distance increases. It is presumed that the shorter the mesh structure, the stronger the network structure and the higher the elastic modulus, and the better the scratch resistance, stain resistance, and abrasion resistance. The weight average molecular weight of the urethane (meth) acrylate oligomer can be determined by gel permeation chromatography measurement (GPC measurement), and a more detailed measurement method will be shown in the examples below.

[Compound (A)]
The compound (A) used for producing the urethane (meth) acrylate oligomer of the present invention is a polyisocyanate. Polyisocyanate is a compound having a total of two or more isocyanate groups and / or substituents containing an isocyanate group in one molecule. As the compound (A), one kind may be used, or two or more kinds may be used. In the present invention, isocyanate groups and substituents containing isocyanate groups may be collectively referred to as "isocyanate groups". Further, in compound (A), two or more isocyanate groups may be the same or different.

Examples of the substituent containing an isocyanate group include an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 1 to 5 carbon atoms, and an alkoxyl group having 1 to 5 carbon atoms, which contain one or more isocyanate groups. Among these, an alkyl group having 1 to 5 carbon atoms containing one or more isocyanate groups is preferable, and an alkyl group having 1 to 3 carbon atoms containing one or more isocyanate groups is particularly preferable.

The type of polyisocyanate is not particularly limited, and examples thereof include chain aliphatic polyisocyanates, aromatic polyisocyanates, and alicyclic polyisocyanates, and even if one of these is used, two or more of them can be combined. May be used. Among these, the compound (A) preferably contains an alicyclic polyisocyanate from the viewpoint of increasing the weather resistance and hardness of the obtained cured product.

A chain aliphatic polyisocyanate is a compound having a chain aliphatic structure and two or more isocyanate groups bonded thereto. The chain aliphatic polyisocyanate is preferable from the viewpoint of enhancing the weather resistance of the cured film obtained by curing the curable composition and imparting stretchability. The chain aliphatic structure of the chain aliphatic polyisocyanate is not particularly limited, but is preferably a linear or branched alkylene group having 1 to 6 carbon atoms. Examples of such chain aliphatic polyisocyanates include aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and diisocyanate diisocyanate, and aliphatic triisocyanates such as tris (isocyanate hexyl) isocyanurate. Isocyanate can be mentioned. These may be used alone or in combination of two or more.

Aromatic polyisocyanates are compounds having an aromatic structure and two or more isocyanate groups attached thereto. The aromatic structure of the aromatic polyisocyanate is not particularly limited, but is preferably an aromatic structure having 6 to 13 carbon atoms. Examples of such aromatic polyisocyanates include aromatic diisocyanates such as tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, m-phenylene diisocyanate, and naphthalene diisocyanate. Aromatic polyisocyanates are preferable from the viewpoint of increasing the mechanical strength of the cured film obtained by curing the curable composition, and examples of such aromatic polyisocyanates include tolylene diisocyanate and diphenylmethane diisocyanate. These may be used alone or in combination of two or more.

The alicyclic polyisocyanate is a compound having an alicyclic structure and two or more isocyanate groups. The alicyclic structure of the alicyclic polyisocyanate is not particularly limited, but is preferably 5 to 15 carbon atoms, and more preferably 6 or more carbon atoms. Further, the number of carbon atoms is more preferably 14 or less, and particularly preferably 13 or less carbon atoms. Further, the alicyclic structure is preferably a cycloalkylene group. Examples of the polyisocyanate having an alicyclic structure include diisocyanates having an alicyclic structure such as bis (isocyanatemethyl) cyclohexane, cyclohexanediisocyanate, bis (isocyanatecyclohexyl) methane, and isophorone diisocyanate, and tris (isocyanate isophorone) isocyanurate. Examples thereof include triisocyanates having an alicyclic structure of. Among these, it is preferable to contain isophorone diisocyanate.

[Compound (B)]
The compound (B) used for producing the urethane (meth) acrylate oligomer of the present invention is an aliphatic polyol having a molecular weight of 500 or less. An aliphatic polyol is a compound having an aliphatic structure and two or more hydroxyl groups bonded to the aliphatic structure. The aliphatic structure may be a linear aliphatic structure, a branched chain aliphatic structure, or an alicyclic structure. As the compound (B), one kind may be used, or two or more kinds may be used.

Examples of the compound (B) include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, and 1,8-. Linear fats such as octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,14-tetradecanediol, and 1,16-hexadecanediol. Diols having a group structure; propylene glycol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 1,2-pentane Diols having a branched chain aliphatic structure such as diols, 3-methyl-1,5-pentanediol and 1,8-nonanediol; branched chain aliphatic structures such as trimethylpropane, glycerin, sorbitol, mannitol and pentaerythritol. Compounds having a structure and three or more hydroxyl groups bonded thereto; diols having an alicyclic structure such as cyclopropanediol, cyclohexanediol, cyclohexanedimethanol, hydrogenated bisphenol A, tricyclodecanediol, and adamantyldiol can be mentioned. Be done. Among these, those having a linear aliphatic structure are preferable, and it is particularly preferable to use at least one selected from ethylene glycol, 1,4-butanediol, and 1,12-dodecanediol for scratch resistance after curing. , It is preferable because a curable composition having excellent abrasion resistance and stain resistance can be obtained. Among these, ethylene glycol is the most preferable in terms of stain resistance, and 1 in terms of scratch resistance and abrasion resistance. , 12-Dodecanediol is most preferred. Further, 1,4-butanediol is preferable in that a cured film having an excellent balance of stain resistance, scratch resistance and abrasion resistance can be obtained. In addition, in order to further improve the weather resistance after curing, it is necessary to introduce more compound (C) into the urethane (meth) acrylate oligomer. For that purpose, the compound (B) preferably contains a diol having a branched chain aliphatic structure. Among the diols having a branched chain aliphatic structure, propylene glycol, neopentyl glycol, 3-methyl-1,5-pentanediol and the like are more preferable from the viewpoint of solution transparency, and neopentyl glycol and 3-methyl-1 are preferable. , 5-Pentanediol and the like are particularly preferable.

In the present invention, the compound (B) is used in an amount of 3% by weight or more based on the total polyol component used as a raw material of the urethane (meth) acrylate oligomer, which is stain resistance, scratch resistance, and abrasion resistance after curing. It is preferable from the viewpoint of improving. Further, in order to further enhance this effect, the compound (B) is more preferably 5% by weight or more, further preferably 10% by weight or more, particularly preferably 20% by weight or more, and 30% by weight. The above is most preferable, and on the other hand, from the viewpoint of ensuring the content of the chemical structure (2), it is preferably 99.95% by weight or less, more preferably 90% by weight or less, and 80% by weight or less. Is particularly preferable. Among these, in particular, when a balance between stain resistance, scratch resistance, and abrasion resistance after curing is required, the compound (B) is preferably 3% by weight or more, preferably 4% by weight or more. It is more preferable, and it is particularly preferable that it is 5% by weight or more. Further, it is preferably 20% by weight or less, more preferably 10% by weight or less, particularly preferably 8% by weight or less, and most preferably 6% by weight or less. Further, in particular, when weather resistance after curing is more required, the compound (B) is 3% by weight based on all the polyol components used as a raw material of the urethane (meth) acrylate oligomer from the viewpoint of ensuring solution transparency. % Or more, more preferably 5% by weight or more, and particularly preferably 10% by weight or more. Further, since good weather resistance can be obtained when the compound (C) is introduced in a larger amount in the urethane (meth) acrylate oligomer, the compound (B) is used as a raw material for the urethane (meth) acrylate oligomer with respect to all the polyol components. , 50% by weight or less, more preferably 40% by weight or less, and particularly preferably 30% by weight or less.

[Compound (C)]
The compound (C) used for producing the urethane (meth) acrylate oligomer of the present invention is a polyol represented by the following formula (3).

In the present invention, it is preferable that the compound (C) is used in an amount of 0.05% by weight or more based on the total polyol component used as a raw material of the urethane (meth) acrylate oligomer from the viewpoint of improving the weather resistance after curing. Further, in order to further enhance this effect, the compound (C) is more preferably 0.1% by weight or more, further preferably 0.2% by weight or more, and more preferably 0.5% by weight or more. On the other hand, it is particularly preferable, from the viewpoint of ensuring the content of the chemical structure (1), it is preferably 50% by weight or less, more preferably 40% by weight or less, and particularly preferably 30% by weight or less. Further, among these, in particular, when a balance of stain resistance, scratch resistance, and abrasion resistance after curing is required, it is more preferably 0.1% by weight or more, and 0.2% by weight or more. Is more preferable, and 0.5% by weight or more is particularly preferable. Further, from the viewpoint of ensuring the content of the chemical structure (1) and ensuring the elastic modulus and stretchability after curing, the compound (C) is used with respect to all the polyol components used as the raw materials of the urethane (meth) acrylate oligomer. It is preferably 8% by weight or less, more preferably 5% by weight or less, and particularly preferably 3% by weight or less. Further, depending on the application, it is necessary to evaluate the weather resistance after curing under stricter conditions and provide a material having further improved weather resistance after curing. In that case, the compound (C) is preferably 10% by weight or more, more preferably 15% by weight or more, and more preferably 20% by weight, based on the total polyol component used as a raw material of the urethane (meth) acrylate oligomer. % Or more is particularly preferable. Further, from the viewpoint of ensuring the content of the chemical structure (1), it is preferably 50% by weight or less, more preferably 40% by weight or less, and particularly preferably 30% by weight or less.
That is, in the urethane (meth) acrylate oligomer of the present invention, the structural unit derived from the compound (C) is 0.05 with respect to the structural unit derived from all the polyol components used as the raw material of the urethane (meth) acrylate oligomer. It is preferably contained in an amount of about 50% by weight, particularly 0.1 to 40% by weight, particularly 0.2 to 30% by weight, and more preferably 0.5% by weight or more.

[Compound (D)]
The compound (D) is not particularly limited as long as it is a compound having a hydroxyl group and a (meth) acryloyl group. As the compound (D), one kind may be used, or two or more kinds may be used.

Examples of the compound (D) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, and cyclohexanedimethanol mono. Meta) acrylate, addition reaction product of 2-hydroxyethyl (meth) acrylate and caprolactone, addition reaction product of 4-hydroxybutyl (meth) acrylate and caprolactone, bisphenol A diglycidyl ether diacrylate, mono (meth) of glycol Examples thereof include acrylate, glycerin (meth) acrylate, glycerinji (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, and dipentaerythritol penta (meth) acrylate. Among these, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol A chain aliphatic structure or a cyclic aliphatic structure such as a hydroxyalkyl (meth) acrylate having an alkylene group having 2 to 4 carbon atoms between a (meth) acryloyl group such as a penta (meth) acrylate and a hydroxyl group, and a cyclic aliphatic structure, and the like. An epoxy (meth) obtained by reacting an epoxy compound selected from an epoxy compound having an aromatic structure with a compound having a (meth) acryloyl group and a carboxyl group (in the present invention, (meth) acrylic acid is contained). Examples include acrylate.

Among these, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol A machine for curing films from which hydroxyalkyl (meth) acrylates having an alkylene group having 2 to 4 carbon atoms between a (meth) acryloyl group such as penta (meth) acrylate and a hydroxyl group and epoxy (meth) acrylate can be obtained. An epoxy (meth) acrylate obtained by reacting an epoxy compound having a chain aliphatic structure having 2 to 12 carbon atoms with a compound having a (meth) acryloyl group and a carboxyl group is particularly preferable from the viewpoint of target strength. It is preferable in that the curability of the urethane (meth) acrylate oligomer can be improved. The chain aliphatic structure may be a linear aliphatic structure or a branched chain aliphatic structure.

Examples of the epoxy compound used for obtaining the epoxy (meth) acrylate having a chain aliphatic structure having 2 to 12 carbon atoms of the compound (D) include ethylene glycol diglycidyl ether and 1,3-propanediol diglycidyl ether. , 1,4-Butanediol diglycidyl ether, 1,5-pentanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,7-heptanediol diglycidyl ether, 1,8-octanediol diglycidyl ether , 1,9-Nonandiol diglycidyl ether, 1,10-decanediol diglycidyl ether, 1,11-undecanediol diglycidyl ether, 1,12-dodecanediol diglycidyl ether, etc. Epoxy compounds; branches of propylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 3-methyl-1,5-pentanediol diglycidyl ether, trimethylpropan triglycidyl ether, glycerin triglycidyl ether, pentaerythritol tetraglycidyl ether, etc. Examples thereof include an epoxy compound having a chain aliphatic structure.

Among these, epoxys having a chain aliphatic structure having 4 to 6 carbon atoms, such as 1,4-butanediol diglycidyl ether, 1,5-pentanediol diglycidyl ether, and 1,6-hexanediol diglycidyl ether. The compound is preferable from the viewpoint of curability of the urethane (meth) acrylate oligomer.

Examples of the compound having a (meth) acryloyl group and a carboxyl group used as a raw material of the compound (D) include (meth) acrylic acid; carboxymethyl (meth) acrylate, carboxyethyl (meth) acrylate, and carboxypropyl (meth). Carboxylalkyl (meth) acrylates such as acrylates and carboxypropyl (meth) acrylates; hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylates, hydroxypropyl (meth) acrylates and hydroxybutyl (meth) acrylates, and phthalic anhydride , Reactants with carboxylic acids anhydride such as succinic anhydride and maleic anhydride, and the like. These may be used alone or in combination of two or more. Among these, acrylic acid is particularly preferable from the viewpoint of curability of the urethane (meth) acrylate oligomer from which a compound having an acryloyl group can be obtained.

The epoxy (meth) acrylate of compound (D) is available as a commercial product. Examples of applicable commercial products include Kayarad (registered trademark) R-167 (manufactured by Nippon Kayaku Co., Ltd.), NK Oligo EA-5520, EA-5321 (manufactured by Shin-Nakamura Chemical Co., Ltd.) and the like.

In the present invention, the compound (D) is used in an amount of 2% by weight or more based on the total polyol component used as a raw material of the urethane (meth) acrylate oligomer, which is stain resistance, scratch resistance, and abrasion resistance after curing. It is preferable from the viewpoint of improving. Further, in order to further enhance this effect, the compound (D) is more preferably 4% by weight or more, further preferably 6% by weight or more, and particularly preferably 8% by weight or more. On the other hand, from the viewpoint of obtaining good stretchability after curing, the compound (D) is more preferably 4% by weight or more, more preferably 6% by weight, based on the total polyol component used as a raw material of the urethane (meth) acrylate oligomer. The above is more preferable, and 8% by weight or more is particularly preferable. Further, it is preferably 20% by weight or less, more preferably 18% by weight or less, further preferably 16% by weight or less, and particularly preferably 14% by weight or less. Further, in order to further improve the weather resistance after curing, the compound (D) is a urethane (meth) from the viewpoint of obtaining good weather resistance when a larger amount of the compound (C) is introduced into the urethane (meth) acrylate oligomer. It is more preferably 4% by weight or more, further preferably 6% by weight or more, and particularly preferably 8% by weight or more, based on the total polyol component used as a raw material of the acrylate oligomer. Further, it is preferably 20% by weight or less, more preferably 18% by weight or less, further preferably 16% by weight or less, and particularly preferably 14% by weight or less.

[Other raw material compounds]
In the raw material compound of the urethane (meth) acrylate oligomer of the present invention, other than the compound (A), the compound (B), the compound (C), and the compound (D) as long as the effect of the present invention is not significantly impaired. A raw material compound may be used. Examples of such other raw material compounds include polyols having an aromatic structure having a molecular weight of 500 or less, and high molecular weight polyols having a molecular weight of more than 500 (hereinafter, these polyols may be referred to as “other polyols”). , Chain extenders and the like.

Examples of the diol having an aromatic structure having a molecular weight of 500 or less include bishydroxyethoxybenzene, bishydroxyethyl terephthalate, and bisphenol A. These may be used alone or in combination of two or more.

Examples of the high molecular weight polyol having a molecular weight exceeding 500 include a polyether polyol, a polyester polyol, a polyether ester polyol, a polycarbonate polyol, a polyolefin polyol, and a silicon polyol. These may be used alone or in combination of two or more.

When the above polymer polyol is used, a polycarbonate polyol is preferable. This polycarbonate polyol is obtained, for example, by reacting at least one carbonate compound selected from the group consisting of alkylene carbonate, diaryl carbonate, and dialkyl carbonate with diols and / or polyether polyols. Examples of diols as raw materials for polycarbonate polyols include ethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, and 1,9. Examples thereof include −nonanediol, 1,4-cyclohexanedimethanol, 1,12-dodecanediol, diethylene glycol, dipropylene glycol, polybutadienediol and the like. Among these, it is preferable to contain at least one selected from 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol from the viewpoint of scratch resistance and abrasion resistance. Polycarbonate polyols are available as commercial products. Examples of applicable commercial products include Duranol (registered trademark) T4671, T4691, 5651, 6001 (manufactured by Asahi Kasei Corporation) and the like.

A chain extender is a compound having two or more active hydrogens that react with an isocyanate group. Examples of the chain extender include low molecular weight diamine compounds having a number average molecular weight of 500 or less, and examples thereof include aromatics such as 2,4- or 2,6-tolylene diamine, xylylene diamine, and 4,4'-diphenylmethanediamine. Group diamines; ethylene diamine, 1,2-propylene diamine, 1,6-hexanediamine, 2,2-dimethyl-1,3-propanediamine, 2-methyl-1,5-pentanediamine, 2,2,4-or An aliphatic diamine such as 2,4,4-trimethylhexanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonandiamine, 1,10-decanediamine; And 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, 4,4'-dicyclohexylmethanediamine, isopropyridenecyclohexyl-4,4'-diamine, 1,4-diaminocyclohexane, 1,3 -Alicyclic diamines such as bisaminomethylcyclohexane and tricyclodecanediamine can be mentioned. These may be used alone or in combination of two or more.

[Manufacturing method of urethane (meth) acrylate oligomer]
The method for producing the urethane (meth) acrylate oligomer of the present invention is not particularly limited, but usually, the compound (B) and the compound (C), and other polyols used as necessary, are converted into urethane in the compound (A). It can be produced by reacting and reacting the obtained product with the compound (D). In addition, the charging ratio of each raw material compound at that time is usually substantially the same as or the same as the composition of the target urethane (meth) acrylate oligomer.

More specifically, the compound (A) is usually reacted with the compound (B) and the compound (C), and other polyols used as needed, under conditions such that the isocyanate group becomes excessive. It can be produced by a method of obtaining a urethane prepolymer having an isocyanate terminal and then reacting the urethane prepolymer having the isocyanate terminal with the compound (D).

According to the above production method, a urethane prepolymer having an isocyanate terminal can be obtained by subjecting the compound (A) to the compound (B) and the compound (C), and other polyols used as needed, in a urethanization reaction. .. The target urethane (meth) acrylate oligomer can be obtained by reacting a urethane prepolymer having an isocyanate group at the terminal with compound (D). According to this production method, the molecular weight can be easily controlled, and the chemical structure represented by the above formula (2) can be introduced into the main clavicle, so that a cured film can be easily obtained. It is preferable for this.

The amount of total isocyanate groups in the urethane (meth) acrylate oligomer and the amount of total functional groups that react with isocyanate groups such as hydroxyl and amino groups are usually theoretically the same molar. However, when the compound (D) has two or more hydroxyl groups, it is preferable to use an excess amount of the compound (D) in order to avoid deterioration of the handleability due to the increase in viscosity due to the increase in molecular weight. .. Therefore, the amount of compound (A), compound (B), compound (C) and compound (D) used as a raw material and other raw material compounds is the amount of total isocyanate groups in the urethane (meth) acrylate oligomer and its reaction. The amount of the total functional groups to be added is an equal amount or an amount such that the equivalent% of the total functional groups with respect to the isocyanate group is 50 to 300 equivalent%.

When producing a urethane (meth) acrylate oligomer, the amount of compound (D) used is 2 mol with respect to the total amount of compound (D) and compounds containing functional groups that react with isocyanate groups in other raw materials. % Or more, more preferably 4 mol% or more, further preferably 5 mol% or more, particularly preferably 6 mol% or more, and most preferably 10 mol% or more. preferable. On the other hand, it is preferably 70 mol% or less, more preferably 50 mol% or less, further preferably 40 mol% or less, and particularly preferably 30 mol% or less. By setting the amount of compound (D) to be used within the above range, the molecular weight of the obtained urethane (meth) acrylate oligomer can be controlled. When the proportion of the compound (D) is large, the molecular weight of the urethane (meth) acrylate oligomer tends to be small, and when the proportion is small, the molecular weight tends to be large.

Further, when a chain extender is used, the total amount of the polyol used is 70 based on the total amount of the compound (B), the compound (C), and the compound including the other polyol components and the chain extender. It is preferably mol% or more, more preferably 80 mol% or more, further preferably 90 mol% or more, and particularly preferably 95 mol% or more.

The ratio of the raw materials used is a guideline for producing the urethane (meth) acrylate oligomer. Actually, it is preferable to finely adjust the raw material blending ratio within the above range according to the desired physical properties.

In the production of urethane (meth) acrylate oligomers, an organic solvent can be used for the purpose of adjusting the viscosity. As the organic solvent, one type may be used alone, or two or more types may be mixed and used. As the organic solvent, any known organic solvent can be used as long as the effects of the present invention can be obtained. Preferred organic solvents include toluene, xylene, ethyl acetate, butyl acetate, cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, N-methylpyrrolidone, dimethylformamide and the like. The organic solvent can usually be used in an amount of 300 parts by weight or less with respect to 100 parts by weight of the solid content in the reaction system.

In the production of the urethane (meth) acrylate oligomer, the total content of the urethane (meth) acrylate oligomer and its raw material compound produced is preferably 20% by weight or more, preferably 40% by weight or more, based on the total amount of the reaction system. More preferably. The upper limit of this total content is usually 100% by weight. When the total content of the urethane (meth) acrylate oligomer and its raw material compound is at least the above lower limit, the reaction rate tends to be high and the production efficiency tends to be improved, which is preferable.

A catalyst can be used in the production of the urethane (meth) acrylate oligomer. The catalyst can be selected from the range in which the effects of the present invention can be obtained, for example, tin-based catalysts such as dibutyltin laurate, dibutyltin dioctate, dioctyltin dilaurate, and dioctyltin dioctate; bismuth tris (2- Examples thereof include bismuth-based catalysts such as ethyl hexanoate). As the catalyst, one type may be used alone, or two or more types may be mixed and used. Of these, the catalyst is preferably dioctyltin dilaurate or bismuthtris (2-ethylhexanoate) from the viewpoint of environmental adaptability, catalytic activity, storage stability and the like. The upper limit of the amount of the catalyst used is usually 2,000 ppm or less, preferably 1,000 ppm or less, and the lower limit is usually 10 ppm or more, preferably 30 ppm or more, based on the total content of the raw material compounds. In the case of producing by the above method, particularly when the compound (A) and the compound (B) are reacted to obtain a urethane prepolymer, or when the compound (C) is reacted with the urethane prepolymer. It is preferable to use the catalyst in any of the reactions when the compound (D) is reacted with the urethane prepolymer.

When a compound containing a (meth) acryloyl group such as compound (D) is used in the reaction system during the production of the urethane (meth) acrylate oligomer, it is preferable to use a polymerization inhibitor in combination. Examples of such a polymerization inhibitor include phenols such as hydroquinone, methylhydroquinone, hydroquinone monoethyl ether and dibutylhydroxytoluene, amines such as phenothiazine and diphenylamine, copper salts such as copper dibutyldithiocarbamate, and manganese acetate. Examples thereof include manganese salts, nitro compounds and nitroso compounds. As the polymerization inhibitor, one type may be used alone, or two or more types may be mixed and used. Of these, phenols are preferable as the polymerization inhibitor. The upper limit of the amount of the polymerization inhibitor used is usually 3,000 ppm or less, preferably 1,000 ppm or less, particularly preferably 500 ppm or less, while the lower limit is usually 50 ppm or less with respect to the total content of the raw material compound. As mentioned above, it is preferably 100 ppm or more.

In the production of the urethane (meth) acrylate oligomer, the reaction temperature is preferably 20 ° C. or higher, preferably 40 ° C. or higher, and more preferably 60 ° C. or higher. When the reaction temperature is at least the above lower limit value, the reaction rate tends to be high and the production efficiency tends to be improved, which is preferable. The reaction temperature is preferably 120 ° C. or lower, more preferably 100 ° C. or lower. When the reaction temperature is not more than the above upper limit value, side reactions such as allophanation reaction are less likely to occur, which is preferable. When the reaction system contains an organic solvent, the reaction temperature is preferably equal to or lower than the boiling point of the organic solvent, and when a compound having a (meth) acryloyl group such as compound (D) is contained (meth). ) The temperature is preferably 70 ° C. or lower from the viewpoint of preventing the acryloyl group from reacting excessively. The reaction time is usually 5 to 20 hours.

[Curable composition]
The curable composition of the present invention contains at least the above-mentioned urethane (meth) acrylate oligomer of the present invention and an organic solvent.

[Organic solvent]
The curable composition of the present invention contains an organic solvent. By using an organic solvent, the urethane (meth) acrylate oligomer is satisfactorily dissolved, and as will be described later, the viscosity for forming a coating film when the urethane (meth) acrylate oligomer is irradiated with active energy rays and cured. Can be adjusted to obtain a uniform cured film.

As the organic solvent, any known organic solvent can be used as long as the effects of the present invention can be obtained. An organic solvent having a solubility parameter (hereinafter referred to as “SP value”) of 8.0 to 11.5 is preferable. An SP value of 8 or more is preferable from the viewpoint of solubility of the urethane (meth) acrylate oligomer, while a SP value of 11.5 or less is preferable from the viewpoint of solution transparency. Examples of the organic solvent in the above range include toluene (SP value: 9.1), xylene (SP value: 9.1), ethyl acetate (SP value: 8.7), and butyl acetate (SP value: 8.7). ), Cyclohexanone (SP value: 9.8), Methylethylketone (SP value: 9.0), Methylisobutylketone (SP value: 8.7), N-methylpyrrolidone (SP value: 11.2), Isopropyl alcohol (SP value: 11.2) SP value: 11.5) and the like. In the present invention, the SP value represents the solubility parameter, and the value is calculated by the method proposed by Fedors et al. Specifically, it is a value obtained by referring to "POLYMER ENGINEERING AND SCIENCE, FEBRUARY, 1974, Vol. 14, No. 2, ROBERT F. FEDORS. (Pages 147 to 154)". The SP value is a physical characteristic value determined by the content of the hydrophobic group or the hydrophilic group of the molecule, and when a mixed solvent is used, it means a value as a mixture.

The organic solvent can usually be used so that the solid content concentration of the curable composition is 5 to 90% by weight, and the solid content concentration is preferably 10% by weight or more, more preferably 15% by weight or more. On the other hand, it is preferably 80% by weight or less, more preferably 70 parts by weight or less, and further preferably 60% by weight or less. The "solid content" here means not only the urethane (meth) acrylate oligomer but also all the components except the organic solvent, and not only the solid state but also the semi-solid or viscous liquid material. It shall include.

[Other ingredients]
The curable composition of the present invention may be referred to as a component other than the urethane (meth) acrylate oligomer and the organic solvent (in the present invention, "other components", as long as the effect of the present invention is not significantly impaired. Yes.) May be contained. Other components include, for example, an active energy ray-reactive monomer, an active energy ray-curable oligomer (excluding the urethane (meth) acrylate oligomer of the present invention), a polymerization initiator, a photosensitizer, an epoxy compound, and other components. Additives and the like can be mentioned.

In the curable composition of the present invention, the content of the urethane (meth) acrylate oligomer is the total amount of all components (solid content) excluding the organic solvent in the curable composition, such as the active energy ray-reactive component (hereinafter, "" It is preferably 40% by weight or more, more preferably 60% by weight or more, based on the total amount of the composition. When the content of the urethane (meth) acrylate oligomer is at least the above lower limit value, the curability becomes good, and the mechanical strength of the cured film does not become too high, and the three-dimensional processability tends to improve. Therefore, it is preferable. The upper limit of the content of the urethane (meth) acrylate oligomer is 100% by weight.

Further, in the curable composition of the present invention, the total content of the active energy ray-reactive component containing the urethane (meth) acrylate oligomer is excellent in the curing rate and surface curability of the composition, and no tack remains. From this aspect, it is preferably 60% by weight or more, more preferably 80% by weight or more, further preferably 90% by weight or more, and 95% by weight or more, based on the total amount of the composition. Is particularly preferred. The upper limit of this content is 100% by weight.

As the active energy ray-reactive monomer, any known active energy ray-reactive monomer can be used as long as the effect of the present invention can be obtained. These active energy ray-reactive monomers are used for the purpose of adjusting the physical properties such as the hydrophobicity of the urethane (meth) acrylate oligomer and the hardness and elongation of the cured film when the obtained composition is used as the cured film. To. As the active energy ray-reactive monomer, one type may be used alone, or two or more types may be mixed and used.

Examples of such active energy ray-reactive monomers include vinyl ethers, (meth) acrylamides, and (meth) acrylates, and specific examples thereof include styrene, α-methylstyrene, and α-chlorostyrene. , Vinyl toluene, divinylbenzene and other aromatic vinyl monomers; vinyl acetate, butyrate vinyl, N-vinylformamide, N-vinylacetamide, N-vinyl-2-pyrrolidone, N-vinylcaprolactam, divinyl adipate and other vinyl Ester monomers; Vinyl ethers such as ethyl vinyl ether and phenyl vinyl ether; Allyl compounds such as diallyl phthalate, trimethylpropandiallyl ether and allyl glycidyl ether; (meth) acrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylic Amid, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N-t-butyl (meth) acrylamide, (meth) acrylic morpholine, methylenebis (meth) acrylamide, etc. (Meta) acrylamides; (meth) acrylic acid, methyl (meth) acrylic acid, ethyl (meth) acrylic acid, propyl (meth) acrylic acid, (meth) acrylic acid-n-butyl, (meth) acrylic acid- i-butyl, (meth) acrylate-t-butyl, (meth) acrylate hexyl, (meth) acrylate-2-ethylhexyl, (meth) acrylate lauryl, (meth) acrylate stearyl, (meth) acrylate Tetrahydrofurfuryl, morpholyl (meth) acrylate, -2-hydroxyethyl (meth) acrylate, -2-hydroxypropyl (meth) acrylate, -4-hydroxybutyl (meth) acrylate, glycidyl (meth) acrylate , (Meta) dimethylaminoethyl acrylate, (meth) diethylaminoethyl acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, tricyclodecane (meth) acrylate, ( Dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentanyl (meth) acrylate, allyl (meth) acrylate, -2-ethoxyethyl (meth) acrylate, (meth) Monofunctional (meth) ac of isobornyl acrylate, phenyl (meth) acrylate, etc. Relate; and di (meth) acrylate ethylene glycol, di (meth) acrylate diethylene glycol, di (meth) acrylate triethylene glycol, di (meth) acrylate tetraethylene glycol, di (meth) acrylate polyethylene glycol ( n = 5-14), propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, di (meth) Polypropylene glycol acrylate (n = 5-14), di (meth) acrylate-1,3-butylene glycol, di (meth) acrylate-1,4-butanediol, di (meth) polybutylene acrylate (polybutylene glycol di (meth)) n = 3 to 16), poly (1-methylbutylene glycol) di (meth) acrylic acid (n = 5 to 20), di (meth) acrylic acid-1,6-hexanediol, di (meth) acrylic acid- 1,9-Nonandiol, neopentyl glycol di (meth) acrylate, neopentyl glycol hydroxypivalate di (meth) acrylic acid ester, dicyclopentanediol di (meth) acrylate, tricyclo di (meth) acrylate Decane, bisphenol A diglycidyl ether di (meth) acrylate, 1,4-cyclohexanedimethanol diglycidyl ether di (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, 1,4-butanediol diglycidyl ether di (Meta) Acrylate, 1,6-Hexanediol Diglycidyl Ether Di (Meta) Acrylate, Trimethylol Propanetri (Meta) Acrylate, Pentaerythritol Tri (Meta) Acrylate, Pentaerythritol Tetra (Meta) Acrylate, Ditrimethylol Propantetra (meth) Meta) Acrylate, Dipentaerythritol Tetra (Meta) Acrylate, Dipentaerythritol Penta (Meta) Acrylate, Dipentaerythritol Hexa (Meta) Acrylate, Trimethylol Propanetrioxyethyl (Meta) Acrylate, Trimethylol Propanetrioxypropyl (Meta) ) Acrylate, Trimethylol Propanepolyoxyethyl (meth) Acrylate, Trimethylol Propanepolyoxypropyl (Meta) Acrylate, Tris (2-Hydroxyethyl) Isocyanurate Tri (Meta) Acrylate Rate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate, ethylene oxide-added bisphenol A di (meth) acrylate, ethylene oxide-added bisphenol F di (meth) acrylate, propylene oxide-added bisphenol A di (meth) acrylate, Examples thereof include polyfunctional (meth) acrylates such as propylene oxide-added bisphenol F di (meth) acrylate, tricyclodecanedimethanol di (meth) acrylate, bisphenol A epoxy di (meth) acrylate, and bisphenol F epoxy di (meth) acrylate.

Among these, particularly in applications where the composition of the present invention is required to have coatability, (meth) acryloylmorpholin, tetrahydrofurfuryl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate. , (Meta) trimethylcyclohexyl acrylate, (meth) phenoxyethyl acrylate, (meth) tricyclodecane acrylate, dicyclopentenyl (meth) acrylate, isobornyl (meth) acrylate, (meth) acrylamide, etc. Monofunctional (meth) acrylate having a ring structure inside is preferable, while di (meth) acrylic acid-1,4-butanediol and di (meth) acrylic are used in applications where the mechanical strength of the obtained cured film is required. Acid-1,6-hexanediol, di (meth) acrylate-1,9-nonanediol, di (meth) acrylate neopentylglycol, di (meth) acrylate tricyclodecane, 1,4-cyclohexanedimethanol Diglycidyl ether di (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, 1,4-butanediol diglycidyl ether di (meth) acrylate, 1,6-hexanediol diglycidyl ether di (meth) acrylate, Trimethylol propantri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) Polyfunctional (meth) acrylates such as acrylates are preferable, and in applications where the stretchability of the obtained cured film is required, polyethylene glycol di (meth) acrylate (n = 5-14), polypropylene glycol di (meth) acrylate (meth) Polyethers such as n = 5-14), polybutylene glycol di (meth) acrylate (n = 3-16), polypoly (meth) acrylate (1-methylbutylene glycol) (n = 5-20) Meta) acrylates are preferable.

In the curable composition of the present invention, the content of the active energy ray-reactive monomer is relative to the total amount of the composition from the viewpoint of adjusting the viscosity of the composition and adjusting the physical properties such as hardness and elongation of the obtained cured film. It is preferably 50% by weight or less, more preferably 30% by weight or less, further preferably 20% by weight or less, and particularly preferably 10% by weight or less.

Examples of the active energy ray-curable oligomer include epoxy (meth) acrylate-based oligomers, acrylic (meth) acrylate-based oligomers, polyester (meth) acrylate-based oligomers, polycarbonate (meth) acrylate-based oligomers, and polybutadiene (meth) acrylate-based oligomers. Polyether (meth) acrylates (excluding those described in the active energy ray-reactive monomer) can be mentioned. As the active energy ray-curable oligomer, one type may be used alone, or two or more types may be mixed and used.

In the curable composition of the present invention, the content of the active energy ray-reactive oligomer is 50% by weight or less based on the total amount of the composition from the viewpoint of adjusting physical properties such as hardness and elongation of the obtained cured film. It is preferably 30% by weight or less, more preferably 20% by weight or less, and particularly preferably 10% by weight or less.

The polymerization initiator is mainly used for the purpose of improving the initiation efficiency of a polymerization reaction that proceeds by irradiation with active energy rays such as ultraviolet rays and electron beams. As the polymerization initiator, a photoradical polymerization initiator which is a compound having a property of generating radicals by light is generally used, and any known photoradical polymerization initiator can be used as long as the effects of the present invention can be obtained. Is. As the polymerization initiator, one type may be used alone, or two or more types may be mixed and used. Further, a photoradical polymerization initiator and a photosensitizer may be used in combination.

Examples of the photoradical polymerization initiator include benzophenone, 2,4,6-trimethylbenzophenone, 4,4-bis (diethylamino) benzophenone, 4-phenylbenzophenone, methyl orthobenzoylbenzoate, thioxanthone, diethylthioxanthone, isopropylthioxanthone, and chloro. Thioxanthone, 2-ethylanthraquinone, t-butylanthraquinone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 1-hydroxycyclohexylphenylketone, benzoinmethylether, benzoinethyl Ether, benzoin isopropyl ether, benzoin isobutyl ether, methylbenzoylformate, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one, 2,6-dimethylbenzoyldiphenylphosphenyl oxide, 2 , 4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, and 2- Examples thereof include hydroxy-1- [4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl] -2-methyl-propan-1-one.

Among these, benzophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenylketone, 2,4,6 are available because the curing rate is high and the crosslink density can be sufficiently increased. -Trimethylbenzoyldiphenylphosphine oxide and 2-hydroxy-1- [4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl] -2-methyl-propan-1-one Preferably, 1-hydroxycyclohexylphenylketone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and 2-hydroxy-1- [4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl ] -2-Methyl-Propane-1-one is more preferred.

When the curable composition contains a compound having a cationically polymerizable group such as an epoxy group together with a radically polymerizable group, a photocationic polymerization initiator is included as the polymerization initiator together with the above-mentioned photoradical polymerization initiator. It may be. As the photocationic polymerization initiator, any known photocationic polymerization initiator can be used as long as the effect of the present invention is not significantly impaired.

The content of these polymerization initiators in the curable composition of the present invention is preferably 10 parts by weight or less, preferably 5 parts by weight or less, based on 100 parts by weight of the total of the active energy ray-reactive components. More preferably. When the content of the polymerization initiator is not more than the above upper limit value, the mechanical strength is unlikely to be lowered by the decomposition product of the initiator, which is preferable.

The photosensitizer can be used for the same purpose as the polymerization initiator. As the photosensitizer, any known photosensitizer can be used as long as the effects of the present invention can be obtained. Examples of such a photosensitizer include ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, and amyl 4-dimethylaminobenzoate. And 4-dimethylaminoacetophenone and the like. As the photosensitizer, one type may be used alone, or two or more types may be mixed and used.

In the curable composition of the present invention, the content of the photosensitizer is preferably 10 parts by weight or less, preferably 5 parts by weight or less, based on 100 parts by weight of the total of the active energy ray-reactive components. Is more preferable. When the content of the photosensitizer is not more than the above upper limit value, the mechanical strength is less likely to decrease due to the decrease in the crosslink density, which is preferable.

The additive is arbitrary as long as the effects of the present invention can be obtained, and various materials added to the composition used for the same purpose can be used as the additive. As the additive, one type may be used alone, or two or more types may be mixed and used. Examples of such additives include glass fibers, glass beads, silica, alumina, calcium carbonate, mica, zinc oxide, titanium oxide, talc, kaolin, metal oxides, metal fibers, iron, lead, metal powder and the like. Fillers: Carbon materials such as carbon fibers, carbon black, graphite, carbon nanotubes, and fullerenes such as C60 (fillers and carbon materials may be collectively referred to as "inorganic components"); antioxidants, Heat stabilizer, UV absorber, hindered amine light stabilizer (HALS), fingerprint resistant agent, surface hydrophilic agent, antistatic agent, slippering agent, plasticizing agent, mold release agent, defoaming agent, leveling agent, sedimentation prevention Modifiers such as agents, surfactants, thixotropy-imparting agents, lubricants, flame retardants, flame retardant aids, polymerization inhibitors, fillers, silane coupling agents; colorants such as pigments, dyes, hue adjusters, etc. ; And curing agents, catalysts, curing accelerators, etc. necessary for the synthesis of monomers and / or oligomers thereof, or inorganic components; and the like.

In the curable composition of the present invention, the content of the additive is preferably 10 parts by weight or less, preferably 5 parts by weight or less, based on 100 parts by weight of the total of the active energy ray-reactive components. Is more preferable. When the content of the additive is not more than the above upper limit value, the mechanical strength is less likely to decrease due to the decrease in the crosslink density, which is preferable.

The method for incorporating an optional component such as the above-mentioned additive into the curable composition of the present invention is not particularly limited, and examples thereof include conventionally known mixing and dispersing methods. In addition, in order to disperse the arbitrary component more reliably, it is preferable to carry out the dispersion treatment using a disperser. Specifically, for example, two-roll, three-roll, bead mill, ball mill, sand mill, pebble mill, ultrasonic mill, sand grinder, seg barrier traitor, planetary stirrer, high-speed impeller disperser, high-speed stone mill, high-speed impact mill. , A method of processing with a kneader, a homogenizer, an ultrasonic disperser, or the like.

[viscosity]
The viscosity of the curable composition of the present invention can be appropriately adjusted according to the use and mode of use of the curable composition, but from the viewpoint of handleability, coatability, moldability, three-dimensional formability, etc., the E-type The viscosity of the viscometer (rotor 1 ° 34'x R24) at 25 ° C. is preferably 5 mPa · s or more, more preferably 10 mPa · s or more, and 50,000 mPa · s or less. It is preferably 10,000 mPa · s or less, more preferably 5,000 mPa · s or less, and particularly preferably 2,000 mPa · s or less. The viscosity of the curable composition can be adjusted, for example, by the content of the urethane (meth) acrylate oligomer according to the present invention, the type of the above-mentioned optional component, the blending ratio thereof, and the like.

[Coating method]
Examples of the coating method of the curable composition of the present invention include a bar coater method, an applicator method, a curtain flow coater method, a roll coater method, a spray method, a gravure coater method, a comma coater method, a reverse roll coater method, and a lip coater method. Known methods such as a die coater method, a slot die coater method, an air knife coater method, and a dip coater method can be applied, and among them, the bar coater method and the gravure coater method are preferable.

[Cured product / laminated body]
A cured product can be obtained by irradiating the above-mentioned curable composition of the present invention with active energy rays (hereinafter, may be referred to as "cured product of the present invention"). Examples of the active energy ray used for curing the curable composition include infrared rays, visible rays, ultraviolet rays, X-rays, electron beams, α rays, β rays, and γ rays. From the viewpoint of equipment cost and productivity, it is preferable to use an electron beam or ultraviolet rays, and the light source is an electron beam irradiation device, an ultra-high pressure mercury lamp, a high pressure mercury lamp, a medium pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, Ar. Lasers, He-Cd lasers, solid-state lasers, xenon lamps, high-frequency induction mercury lamps, sunlight and the like are suitable.

The irradiation amount of the active energy ray can be appropriately selected according to the type of the active energy ray. For example, when it is cured by electron beam irradiation, the irradiation amount is preferably 1 to 15 Mrad. Further, when it is cured by irradiation with ultraviolet rays, it is preferably ^{50 to 1,500 mJ / cm 2.}

When curing, it may be under any atmosphere of air or an inert gas such as nitrogen or argon. Further, irradiation may be performed in a closed space between the film or glass and the metal mold.

In the present invention, the thickness of the cured film is appropriately determined according to the intended use, but the lower limit is preferably 1 μm, more preferably 2 μm. The upper limit is preferably 100 μm, more preferably 50 μm, and particularly preferably 20 μm. When the film thickness is equal to or more than the above lower limit value, the appearance of design and functionality after three-dimensional processing tends to be good, while when the film thickness is equal to or less than the above upper limit value, internal curability and three-dimensional processing suitability tend to be good. Tends to be good.

Further, a laminate can be obtained by curing the curable composition of the present invention on a substrate (hereinafter, may be referred to as "laminate of the present invention"). The laminate of the present invention is not particularly limited as long as the cured product of the present invention is formed on the base material, and layers other than the base material and the cured product of the present invention are placed between the base material and the cured product of the present invention. It may be held in or outside it. Further, the laminated body may have a plurality of layers of a base material and a cured product of the present invention.

As a method of obtaining a laminate having a plurality of layers of cured products, a method of laminating all the layers in an uncured state and then curing with an active energy ray, a method of curing the lower layer with an active energy ray, or after semi-curing. A known method such as a method of applying an upper layer and curing it again with active energy rays, a method of applying each layer to a release film or a base film, and then laminating the layers in an uncured or semi-cured state is applied. Although it is possible, from the viewpoint of enhancing the adhesion between layers, a method of laminating in an uncured state and then curing with active energy rays is preferable. As a method of laminating in an uncured state, a known method such as sequential coating in which the lower layer is applied and then the upper layer is applied in layers, or simultaneous multi-layer coating in which two or more layers are applied in layers at the same time from multiple slits is applied. It is possible, but not limited to this.

Examples of the base material include polyesters such as polyethylene terephthalate and polybutylene terephthalate; polyolefins such as polypropylene and polyethylene; and various plastics such as nylon, polycarbonate and (meth) acrylic resin, glass and metals. Of these, polyethylene terephthalate is preferable. Further, the shape of these base materials may be a flat one such as a film shape or a sheet shape, or may be molded into various shapes.

In the present invention, since the obtained cured product is excellent in stretchability, it is preferable to stretch the cured product to obtain a cured film, and in particular, it is preferable to produce a cured film by the following method. A preferred method for producing a cured film is a step of applying the curable composition of the present invention onto a substrate, a step of irradiating the curable composition with active energy rays to obtain a cured product, and a step of stretching the cured product. It is due to going through. Since the urethane (meth) acrylate oligomer of the present invention has a stretchability after curing that can follow the deformation during three-dimensional processing, it exhibits good stretchability in the step of stretching the cured product. , The obtained cured film has particularly good suitability for deformation during three-dimensional processing.

In the present invention, in the above-mentioned method for producing a cured film, each of the step of applying the curable composition on the substrate and the step of irradiating the curable composition with active energy rays to obtain a cured product , Can be performed under the above-mentioned conditions. Further, in the method for producing a cured film, the step of stretching the cured product can be usually heated and stretched under the conditions of 60 to 200 ° C., preferably 100 to 180 ° C. As this stretching method, a known method can be used, and for example, any method such as insert molding, in-mold molding, overlay molding, blow molding, vacuum forming and the like can be used.

The urethane (meth) acrylate oligomer of the present invention, the cured product obtained by using the curable composition, and the laminate can be suitably used as a coating substitute film. For example, it can be effectively applied to various materials such as interior / exterior building materials, automobiles, home appliances, and information and electronic materials. In particular, the cured film of the present invention is useful as a decorative film using this as a top coat layer.

Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to the following Examples. The values of various production conditions and evaluation results in the following examples have meanings as preferable values of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the above-mentioned upper limit or lower limit value. , The range specified by the combination of the values of the following examples or the values of the examples may be used.

[Measurement method of physical properties / characteristics]
The methods for measuring and evaluating the physical properties and characteristics of the urethane (meth) acrylate oligomer and the cured film in the following Examples and Comparative Examples are as follows.

<Physical characteristics of urethane (meth) acrylate oligomer>
1-1) Weight average molecular weight (Mw), number average molecular weight (Mn) of urethane (meth) acrylate oligomer
GPC (Tosoh's "HLC-8120 GPC") using tetrahydrofuran (THF) as the solvent, polystyrene as the standard sample, and TSKgel superH1000 + H2000 + H3000 as the column, at a liquid feeding rate of 0.5 mL / min and a column oven temperature of 40 ° C. , The weight average molecular weight and the number average molecular weight (GPC measurement value) of the urethane (meth) acrylate oligomer were measured.

<Physical characteristics of cured film>
2-1) Evaluation of coating film appearance The coating film appearance of the cured film laminated on the polyethylene terephthalate obtained by the film forming methods I and III described later was visually evaluated according to the following criteria.
◯: With a uniform film thickness, no abnormalities such as foreign matter, wrinkles, and loose skin are seen on the coating film surface. Δ: Foreign matter, wrinkles, and wrinkles on the coating film surface when the angle of the laminate is changed or when staring at it with light. Abnormalities such as loose skin are seen. ×: Abnormalities such as foreign matter, wrinkles, and loose skin are seen on the coating film surface.

_{2-2) Evaluation of scratch resistance The haze value measured before the scratch resistance test was set to H 1} for the cured film laminated on the polyethylene terephthalate obtained by the film forming methods I and III described later. On the other hand, in an atmosphere of 23 ° C. and 55% RH, ^{a weight of 200 gf (per area of 4 cm 2} ) was placed on steel wool # 0000, and the cured film surface laminated on the polyethylene terephthalate obtained by the above film forming method I was studied. The haze value measured immediately after rubbing 15 times with a vibration and abrasion tester (manufactured by Toyo Seiki Co., Ltd.) was defined as H ₂ . The difference between H ₂ and H ₁ (ΔH (ΔH = H _2- H ₁ )) was determined and evaluated according to the following criteria. In the above, the haze value was measured using a haze meter (“HAZE METER HM-65W” manufactured by Murakami Color Technology Research Institute Co., Ltd.) in accordance with JIS K7105.
◯: ΔH ≦ 2.0
X: 2.0 <ΔH

2-3) Evaluation of elastic modulus A cured film of the film forming method II described later is cut into a width of 10 mm, and a Tensilon tensile tester (“RTC-1210A” manufactured by Orientec Co., Ltd.) is used to heat the temperature at 23 ° C and the humidity at 55%. A tensile test was performed under the conditions of RH, a tensile speed of 50 mm / min, and a distance between chucks of 50 mm, and the tensile elastic modulus was measured. More specifically, the straight line connecting the stress at 0% elongation and the stress at 0.5% elongation of the stress-strain curve (SS curve) obtained by performing a tensile test under the above conditions is extended to 100. The stress converted at the time of% elongation was taken as the elastic modulus. The elastic modulus is preferably 20% or more.

2-4) Evaluation of stretchability The cured film of the film forming method II described later was cut into a width of 10 mm, and a Tensilon tensile tester (“MX2-500N” manufactured by Imada Co., Ltd.) was used at room temperature and a tensile speed of 50 mm /. The elongation at break was measured by stretching under the condition that the distance between chucks was 50 mm, and the evaluation was performed according to the following criteria.
⊚: Elongation 200% or more ○: Elongation 100% or more and less than 200% ×: Elongation less than 100%

2-5) Evaluation of weather resistance (* 1) A spectrocolorimeter (manufactured by Konica Minolta Co., Ltd., product name "Spectrophoto") was used for the cured film laminated on the polyethylene terephthalate obtained by the film forming method I described later. _{Color tones L 0} , a ₀ , and b ₀ were measured using a meter CM-5 "). Next, using a xenon weather meter (manufactured by Suga Test Instruments Co., Ltd., product name "Super xenon Weather Meter SX2D-75"), it was irradiated for 20 hours (illumination 58 mW / cm ² , temperature 40 ° C, humidity 20%). In a dark state, a total of 24 hours (temperature 40 ° C., humidity 20%) was set as one cycle, and an accelerated light resistance test for 1008 hours (42 cycles) was performed, and the cured film after the test was visually observed. _{The color tones L 1} , a ₁ , and b ₁ were measured while evaluating according to the following criteria. From the result, the degree of change ΔE value was calculated by the following formula and evaluated according to the following criteria.
ΔE = √ {(L _{1 −} L ₀ ) ² + (a _{1 −} a ₀ ) ² + (b ₁ − b ₀ ) ² }
<ΔE>
◯: ΔE is less than 1.0 Δ: ΔE is 1.0 or more and less than 1.2 ×: ΔE is 1.2 or more <Appearance>
○: No change ×: Change

2-6) Evaluation of weather resistance (* 2) A spectrocolorimeter (manufactured by Konica Minolta Co., Ltd., product name "Spectrophoto") was used for the cured film laminated on polyethylene terephthalate obtained by the film forming method III described later. _{The color tone b 0} was measured using the meter CM-5 "). Next, using a metal weather meter (manufactured by Daipla Wintes Co., Ltd., product name "Daipla Metal Weather KU-R4Ci-W") ^{under irradiation with an irradiation intensity of 80 mW / cm 2} , the following (1) and (2) , (3) is the accelerated light resistance of 72 hours (6 cycles), 168 hours (14 cycles), 192 hours (16 cycles) or 672 hours (56 cycles), with a total of 12 hours of 4 hours each as one cycle. test performed, as well as evaluated according to the following criteria by performing a visual observation of the cured film after the test was measured tone b _1. From the result, the degree of change Δb value was calculated by the following formula and evaluated according to the following criteria.
(1) Temperature 63 ° C, humidity 70%
(2) Temperature 70 ° C, humidity 90%
(3) Temperature 30 ° C, humidity 98% (with shower for 10 seconds before and after (3))
Δb = b ₁ −b ₀
<Δb>
◯: Δb is less than 3.0 ×: Δb is 3.0 or more <Appearance>
○: No change ×: Change

2-7) Evaluation of chemical resistance The cured film laminated on the polyethylene terephthalate obtained by the film forming methods I and III described later was impregnated with ethanol under an atmosphere of 23 ° C. and 55% RH under a load of 500 g. The evaluation was made based on the number of times that the gold cloth (S618-92: manufactured by Toyobo STC) was worn by a Gakushin wear tester, the coating film swelled and peeled off, and the surface of the base material became visible.
◯: 10 times or more
×: Less than 10 times

[Raw materials / solvents]
The raw materials and solvents used in the following Examples and Comparative Examples and their abbreviations are as follows.

(Compound (A))
-IPDI: Isophorone diisocyanate (Product name "VESTANAT IPDI" manufactured by Evonik Degussa Japan)

(Compound (B))
・ 1,4-BD: 1,4-butanediol ・ 3MPD: 3-methyl-1,5-pentanediol

(Compound (C))
-T-33: Polypoly represented by the following formula (3) (Product name "Dinesorb T-33" manufactured by Daiwa Kasei Co., Ltd.)

(Compound (D): Compound having a hydroxyl group and a (meth) acryloyl group)
-R-167: 1,6-hexanediol diglycidyl ether diacrylate (Nippon Kayaku Co., Ltd. "Kayarad (registered trademark) R-167")
-HEA: 2-Hydroxyethyl acrylate (trade name "HEA" manufactured by Osaka Organic Co., Ltd.)

(Other polyols)
-T-35: Polypoly represented by the following formula (4) (Product name "Dinesorb T-35" manufactured by Daiwa Kasei Co., Ltd.)

-T4691: Polycarbonate polyol ("Duranol (registered trademark) T4691" manufactured by Asahi Kasei Corporation)
1,4-butanediol / 1,6-hexanediol = 9/1 (weight ratio)
Number average molecular weight: 1,000
Hydroxy group value: 119.4 mgKOH / g
-PL208: Polycaprolactone polyol ("Plaxel (registered trademark) 208" manufactured by Daicel Chemical Co., Ltd.)
Number average molecular weight: 800
Hydroxy group value: 132.3 mgKOH / g

(Organic solvent)
-MEK: Methyl ethyl ketone (SP value: 9.0)

(Polyfunctional acrylate)
V-300: A mixture containing 40 to 45% by weight of pentaerythritol triacrylate and 35 to 40% by weight of pentaerythritol tetraacrylate as other compounds (catalog value) (Osaka Organic Co., Ltd. "Viscoat (registered trademark) 300"")

(Other active energy ray-reactive monomers)
・ GMA: Glycidyl methacrylate ・ MMA: Methyl methacrylate ・ AA: Acrylic acid

(Photoradical polymerization initiator)
-Irg184: 1-Hydroxy-cyclohexyl-phenyl-ketone (BASF's "Irgacure (registered trademark) 184")

[Example 1]
In a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer, 86.3 g of IPDI and 16.7 g of 1,4-BD were placed, and 258 g of methyl ethyl ketone and bismuth tris (2-ethylhexa) were added. Noate) 0.02 g was added and reacted for 2 hours while heating at 80 ° C. in an oil bath. Then, 155 g of T4691 was added dropwise and the reaction was carried out for 5 hours, then 5.69 g of T-33 and 5.69 g of methyl ethyl ketone were added and the reaction was carried out for 5 hours. After completion of the urethanization reaction, the mixture was cooled to 60 ° C., 0.06 g of bismuth tris (2-ethylhexanoate) and 0.15 g of methyl hydroquinone were further added, and 36.1 g of R-167 was added dropwise to start the reaction. It was. The reaction was carried out in an oil bath at 70 ° C. for 10 hours, and after confirming the end point of the urethanization reaction by the disappearance of the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, 36.3 g of methyl ethyl ketone was added. , A curable composition was obtained. The weight average molecular weight and the number average molecular weight of the urethane acrylate oligomer in the obtained curable composition were measured by the method of 1-1) above. The results obtained are shown in Table-1.

[Example 2]
In a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer, 86.3 g of IPDI and 16.9 g of 1,4-BD were placed, and 261 g of methyl ethyl ketone and bismuth tris (2-ethylhexa) were added. Noate) 0.03 g was added and reacted for 2 hours while heating at 80 ° C. in an oil bath. Then, 158 g of T4691 was added dropwise and the reaction was carried out for 5 hours, then 2.56 g of T-33 and 2.56 g of methyl ethyl ketone were added and the reaction was carried out for 5 hours. After completion of the urethanization reaction, the mixture was cooled to 60 ° C., 0.08 g of bismuth tris (2-ethylhexanoate) and 0.15 g of methyl hydroquinone were further added, and 36.7 g of R-167 was added dropwise to start the reaction. It was. The reaction was carried out in an oil bath at 70 ° C. for 10 hours, and after confirming the end point of the urethanization reaction by the disappearance of the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, 36.4 g of methyl ethyl ketone was added. , A curable composition was obtained. The weight average molecular weight and the number average molecular weight of the urethane acrylate oligomer in the obtained curable composition were measured by the method of 1-1) above. The results obtained are shown in Table-1.

[Comparative Example 4]
In a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer, 84.2 g of IPDI and 16.3 g of 1,4-BD were placed, and 252 g of methyl ethyl ketone and bismuth tris (2-ethylhexa) were added. Noate) 0.02 g was added and reacted for 2 hours while heating at 80 ° C. in an oil bath. Then, 151 g of T4691 was added dropwise and the reaction was carried out for 5 hours, then 12.8 g of T-35 and 12.8 g of methyl ethyl ketone were added and the reaction was carried out for 5 hours. After completion of the urethanization reaction, the mixture was cooled to 60 ° C., 0.06 g of bismuth tris (2-ethylhexanoate) and 0.14 g of methyl hydroquinone were further added, and 35.2 g of R-167 was added dropwise to start the reaction. It was. The reaction was carried out in an oil bath at 70 ° C. for 10 hours, and after confirming the end point of the urethanization reaction by the disappearance of the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, 35.2 g of methyl ethyl ketone was added. , A curable composition was obtained. The weight average molecular weight and the number average molecular weight of the urethane acrylate oligomer in the obtained curable composition were measured by the method of 1-1) above. The results obtained are shown in Table-1.

[Comparative Example 5]
In a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer, 86.3 g of IPDI and 16.7 g of 1,4-BD were placed, and 261 g of methyl ethyl ketone and bismuth tris (2-ethylhexa) were added. Noate) 0.03 g was added and reacted for 2 hours while heating at 80 ° C. in an oil bath. Then, 155 g of T4691 was added dropwise and the reaction was carried out for 5 hours, then 2.56 g of T-35 and 2.56 g of methyl ethyl ketone were added and the reaction was carried out for 5 hours. After completion of the urethanization reaction, the mixture was cooled to 60 ° C., 0.08 g of bismuth tris (2-ethylhexanoate) and 0.15 g of methyl hydroquinone were further added, and 36.1 g of R-167 was added dropwise to start the reaction. It was. The reaction was carried out in an oil bath at 70 ° C. for 10 hours, and after confirming the end point of the urethanization reaction by the disappearance of the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, 36.4 g of methyl ethyl ketone was added. , A curable composition was obtained. The weight average molecular weight and the number average molecular weight of the urethane acrylate oligomer in the obtained curable composition were measured by the method of 1-1) above. The results obtained are shown in Table-1.

[Example 3]
In a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer, 148.4 g of IPDI and 47.3 g of 3MPD were put, and 195.7 g of methyl ethyl ketone and 0.06 g of dioctyl tindilaurate were put. The reaction was carried out for 2 hours while heating at 80 ° C. in an oil bath. Then, 69.7 g of T-33, 69.8 g of methyl ethyl ketone, and 0.11 g of dioctyltin dilaurate were added, and the reaction was carried out for 5 hours. After completion of the urethanization reaction, the mixture was cooled to 60 ° C., 0.24 g of dioctyltin dilaurate and 0.15 g of methylhydroquinone were further added, and 34.1 g of HEA and 34.5 g of methyl ethyl ketone were added dropwise to start the reaction. The reaction was carried out in an oil bath at 70 ° C. for 10 hours, and after confirming the end point of the urethanization reaction by the disappearance of the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, 15 g of Irg184 and methyl ethyl ketone were added. 15 g was added to obtain a curable composition. The weight average molecular weight and the number average molecular weight of the urethane acrylate oligomer in the obtained curable composition were measured by the method of 1-1) above. The results obtained are shown in Table-2.

[Example 4]
In a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer, 133.7 g of IPDI and 35.53 g of 3MPD were put, and 169.3 g of methyl ethyl ketone and 0.05 g of dioctyl tindilaurate were put. The reaction was carried out for 2 hours while heating at 80 ° C. in an oil bath. The reaction was carried out for 5 hours by adding 104.7 g of T-33, 104.8 g of methyl ethyl ketone and 0.09 g of dioctyltin dilaurate. After completion of the urethanization reaction, the mixture was cooled to 60 ° C., 0.16 g of dioctyltin dilaurate and 0.15 g of methylhydroquinone were further added, and 25.6 g of HEA and 25.9 g of methyl ethyl ketone were added dropwise to start the reaction. The reaction was carried out for 10 hours while heating to 70 ° C. in an oil bath, and after confirming the end point of the urethanization reaction by the disappearance of the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, 700 g of V-300 was added. 50 g of Irg184 and 750 g of methyl ethyl ketone were added to obtain a curable composition. The weight average molecular weight and the number average molecular weight of the urethane acrylate oligomer in the obtained curable composition were measured by the method of 1-1) above. The results obtained are shown in Table-2.

[Comparative Example 1]
Put 67.3 g of IPDI, 179 g of methyl ethyl ketone, and 0.03 g of bismuth tris (2-ethylhexanoate) in a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer in an oil bath. The reaction was carried out for 2 hours while heating at 80 ° C. Then, 201 g of PL208 was added dropwise and the reaction was carried out for 5 hours. After completion of the urethanization reaction, the mixture was cooled to 60 ° C., 0.06 g of bismuth tris (2-ethylhexanoate) and 0.15 g of methyl hydroquinone were further added, and 12.2 g of HEA was added dropwise to start the reaction. The reaction was carried out for 10 hours while heating to 70 ° C. in an oil bath, and after confirming the end point of the urethanization reaction by the disappearance of the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, 121 g of methyl ethyl ketone was added and cured. A sex composition was obtained. The weight average molecular weight and the number average molecular weight of the urethane acrylate oligomer in the obtained curable composition were measured by the method of 1-1) above. The results obtained are shown in Table 3.

[Comparative Example 2]
In a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer, 86.2 g of IPDI and 17.1 g of 1,4-BD were placed, and 263 g of methyl ethyl ketone and bismuth tris (2-ethylhexa) were added. Noate) 0.03 g was added and reacted for 2 hours while heating at 80 ° C. in an oil bath. Then, 160 g of T4691 was added dropwise and the reaction was carried out for 5 hours. After completion of the urethanization reaction, the mixture was cooled to 60 ° C., 0.06 g of bismuth tris (2-ethylhexanoate) and 0.15 g of methyl hydroquinone were further added, and 37.2 g of R-167 was added dropwise to start the reaction. It was. The reaction was carried out for 10 hours while heating to 70 ° C. in an oil bath, and after confirming the end point of the urethanization reaction by the disappearance of the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, T-35 was added to 13. 4 g and 37 g of methyl ethyl ketone were added to obtain a curable composition. The weight average molecular weight and the number average molecular weight of the urethane acrylate oligomer in the obtained curable composition were measured by the method of 1-1) above. The results obtained are shown in Table 3.

[Comparative Example 3]
In a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer, 86.2 g of IPDI and 17.1 g of 1,4-BD were placed, and 263 g of methyl ethyl ketone and bismuth tris (2-ethylhexa) were added. Noate) 0.03 g was added and reacted for 2 hours while heating at 80 ° C. in an oil bath. Then, 160 g of T4691 was added dropwise and the reaction was carried out for 5 hours. After completion of the urethanization reaction, the mixture was cooled to 60 ° C., 0.06 g of bismuth tris (2-ethylhexanoate) and 0.15 g of methyl hydroquinone were further added, and 37.2 g of R-167 was added dropwise to start the reaction. It was. The reaction was carried out for 10 hours while heating to 70 ° C. in an oil bath, and after confirming the end point of the urethanization reaction by the disappearance of the peak derived from the isocyanate (NCO) group in the infrared absorption spectrum, 37 g of methyl ethyl ketone was added and cured. A sex composition was obtained. The weight average molecular weight and the number average molecular weight of the urethane acrylate oligomer in the obtained curable composition were measured by the method of 1-1) above. The results obtained are shown in Table 3.

[Comparative Example 6]
175 parts by weight of GMA, 75 parts by weight of MMA, 1.3 parts by weight of dodecyl mercaptan, 1000 parts by weight of butyl acetate and 2, in a four-necked flask equipped with a stirrer, a reflux condenser, a dropping funnel, and a thermometer. After charging 7.5 parts by weight of 2'-azobisisobutyronitrile (hereinafter referred to as AIBN), the temperature is raised under a nitrogen stream for about 1 hour until the temperature inside the system reaches about 90 ° C. for 1 hour. I kept it warm. Next, from a dropping funnel in which a mixed solution consisting of 525 parts by weight of GMA, 225 parts by weight of MMA, 3.7 parts by weight of dodecyl mercaptan and 22.5 parts by weight of AIBN was charged in advance, the mixed solution was mixed under a nitrogen stream in about 2 hours. After dropping into the water and keeping the temperature at the same temperature for 3 hours, 10 parts by weight of AIBN was charged and kept warm for 1 hour. Then, the temperature was raised to 120 ° C. and kept warm for 2 hours. After cooling to 60 ° C., the nitrogen introduction pipe is replaced with an air introduction pipe, and 355 parts by weight of AA, 2.0 parts by weight of methquinone and 5.4 parts by weight of triphenylphosphine are charged and mixed, and then 110 ° C. under air bubbling. The temperature was raised to. After keeping the temperature at the same temperature for 8 hours, 1.4 parts by weight of methquinone was charged, cooled, and ethyl acetate was added so that the non-volatile content became 50% to obtain a polymer solution.
The weight average molecular weight and the number average molecular weight of the polymer in the obtained polymer solution were measured by the method of 1-1) above. The results obtained are shown in Table 3.

(Film formation method I)
The curable trees obtained in Examples 1 and 2 and Comparative Examples 1 to 5 were coated on a polyethylene terephthalate film with a bar coater to form a coating film, and then dried at 60 ° C. for 1 minute to form an electron beam. Using an irradiation device (CB175, manufactured by Eye Graphic Co., Ltd.), the dry coating film is irradiated with an electron beam under the conditions of an acceleration voltage of 165 kV and an irradiation dose of 5 Mrad, and further cured at 23 ° C. for one day to form a cured film. A laminated body in which a cured film having a thickness of about 8 μm was laminated on polyethylene terephthalate was obtained. The physical properties of the obtained cured film of the laminate were evaluated in 2-1), 2-2) and 2-5). These results are shown in Table 1 and Table 3.

(Film formation method II)
The curable compositions obtained in Examples 1 and 2 and Comparative Examples 1 to 5 were coated on a polyethylene terephthalate film with a bar coater to form a coating film, and then pre-dried at 23 ° C. for 5 minutes. After that, it is dried at 60 ° C. for 1 minute, and the dry coating film is irradiated with an electron beam under the conditions of an acceleration voltage of 165 kV and an irradiation dose of 5 Mrad using an electron beam irradiation device (CB175, manufactured by Eye Graphic), and further at 23 ° C. After curing for one day to form a cured film, the cured film was peeled off from the polyethylene terephthalate film to obtain a cured film having a thickness of about 30 μm. The obtained cured film was evaluated for the physical properties of 2-3) and 2-4). These results are shown in Table 1 and Table 3.

(Film formation method III)
The curable tree product obtained in Examples 3 and 4 was coated on a polyethylene terephthalate film with a bar coater to form a coating film, and then dried at 60 ° C. for 1 minute. Using an ultraviolet irradiation device (US5-X1802-X1202, manufactured by Iwasaki Electric Co., Ltd.), a 160 W high-pressure mercury lamp is used to irradiate the ^{dry coating with ultraviolet rays with an integrated irradiation amount of 1000 mJ / cm 2} (wavelength 315 to 380 nm), and further 23. A cured film was formed by curing at ° C. for 1 day to obtain a laminated body in which a cured film having a thickness of about 5 μm was laminated on polyethylene terephthalate. The physical properties of the obtained cured film of the laminated body were evaluated in 2-1), 2-2) and 2-6). These results are shown in Table-2.

(Film formation method IV)
200 parts by weight (100 parts by weight of solid content) of the curable tree obtained in Comparative Example 6, 10 parts by weight of T-35, 1,6-hexanediisocyanate trimer (trade name: Coronate HX, Nippon Polyurethane Industry Co., Ltd.) A curable composition containing 5 parts by weight of a photopolymerization initiator (trade name: Irgacure 184, manufactured by BASF) was heated at 60 ° C. for 5 minutes and then heated at 23 ° C. for 24 hours. After being left to stand, it was heated at 150 ° C. for 30 seconds, and then irradiated with ultraviolet rays under the conditions of 120 w / cm, 6 lamps, a lamp height of 10 cm, and a conveyor speed of 15 m / min, respectively (film forming method I) and (film forming method). A cured film was obtained in the same manner as in II) and (Film formation method III), and the physical properties of 2-1), 2-2), 2-3), 2-4) and 2-6) were evaluated. However, the elastic modulus and stretchability could not be evaluated because they were brittle. These results are shown in Table-1.

In addition, in order to compare with the weather resistance evaluation results of Examples 3 and 4 2-6), the polyethylene terephthalate film (PET base material) on which the coating film was not formed was evaluated in 2-6). The results are shown in Table 2 as Reference Example 1.

Comparative Example 3 is an example in which the compound (C) was not used, but the weather resistance was poor and the ΔE value increased significantly as compared with Examples 1 and 2. Further, in Comparative Example 2, the compound (C) was mixed after completion of the reaction without incorporating the compound (C) into the molecule, but the weather resistance was poor and the ΔE value increased significantly as compared with Comparative Example 4. Further, Comparative Example 1 is an example in which the compound (B) is not used, but the elastic modulus is low and the scratch resistance is poor. Further, Comparative Examples 4 and 5 are examples in which a chemical structure different from the chemical structure (2) is introduced, but with respect to Examples 1 and 2 in which the chemical structure (1) and the chemical structure (2) are introduced. The chemical resistance (ethanol rubbing resistance) was poor.
Further, Comparative Example 6 is an example similar to the technique described in JP-A-2000-109652 described in the background technique, that is, even if a conventional composition is formed by a conventional film forming method, the present invention is used. This is an example in which it is confirmed that the same effect as that of the invention cannot be obtained.
On the other hand, the urethane (meth) acrylate oligomers of Examples 1 to 4 in which the chemical structure (1) and the chemical structure (2) were introduced by using the compound (B) and the compound (C) in combination were evaluated in any of the evaluations. Good results were also obtained.

The urethane (meth) acrylate oligomer of the present invention, the cured product obtained by using the curable composition, and the laminate can be suitably used as a coating substitute film. For example, it can be effectively applied to various materials such as interior / exterior building materials, automobiles, home appliances, and information and electronic materials. In particular, the cured film of the present invention is useful as a decorative film using this as a top coat layer.

Claims (12)

Formula (1) in the chemical structure and formula represented a chemical structure represented by (2) possess a linear aliphatic structure, either branched aliphatic structures or alicyclic structures, 1 One or more urethane containing monomolecular polyol structure (meth) acrylate oligomer.

(In formula (1), X ¹ is an aliphatic structure having a molecular weight of 500 or less, and n is an integer of 2 to 8.) The urethane (meth) acrylate oligomer according to claim 1, which has a weight average molecular weight (Mw) of 1,500 to 30,000. The structural unit derived from the compound (C) represented by the following formula (3) is contained in an amount of 0.05 to 50% by weight based on the structural unit derived from all the polyol components used as the raw material of the urethane (meth) acrylate oligomer. , The urethane (meth) acrylate oligomer according to claim 1 or 2.

A linear aliphatic structure and a branched chain in which the following compound (A), the following compound (B), and the following compound (C) are reacted to obtain a urethane prepolymer, and then the following compound (D) is reacted with the urethane prepolymer. A method for producing a urethane (meth) acrylate oligomer containing one or more monomolecular polyol structures having either an aliphatic structure or an alicyclic structure.
Compound (A): a polyisocyanate compound (B): a molecular weight of 500 or less of an aliphatic polyol compound (C): polyol represented by the following formula (3)

Compound (D): Compound having a hydroxyl group and a (meth) acryloyl group The method for producing a urethane (meth) acrylate oligomer according to claim 4, wherein the compound (C) is used in an amount of 0.05 to 50% by weight based on all the polyol components used as a raw material of the urethane (meth) acrylate oligomer. A curable composition containing the urethane (meth) acrylate oligomer according to any one of claims 1 to 3 and an organic solvent. The curable composition according to claim 6, wherein the solubility parameter of the organic solvent is 8.0 to 11.5. The curable composition according to claim 6 or 7, wherein the solid content concentration is 5 to 90% by weight. A cured product obtained by curing the curable composition according to any one of claims 6 to 8. A laminate having a cured product of the curable composition according to any one of claims 6 to 8 on a substrate. A cured film obtained by stretching the cured product according to claim 9. A step of applying the urethane (meth) acrylate oligomer according to any one of claims 1 to 3 or the curable composition according to any one of claims 6 to 8 onto a substrate, the curable composition. A method for producing a cured film, which comprises a step of irradiating an object with active energy rays to obtain a cured product and a step of stretching the cured product.