JP6520301B2 - Curable composition - Google Patents

Description

The present invention is excellent in the appearance of a coated film after curing, there is no tackiness when it is not cured, and the handling property is good, and it is excellent in abrasion resistance, contamination resistance after curing and after curing and drawing, and three dimensional The present invention relates to a urethane (meth) acrylate oligomer which is also excellent in stretchability after curing for following processing deformation and a curable composition using the same. The present invention also relates to a cured product and a laminate using the urethane (meth) acrylate oligomer and the curable composition, and a method for producing a cured film .

  A curable composition of radical polymerization type can be cured in a short time by irradiation of active energy rays, and can provide a film or molded article excellent in chemical resistance, stain resistance, weather resistance, heat resistance, etc. It is widely used in various surface processing fields and cast molded article applications. Among such curable compositions, from the viewpoint of curability and working efficiency, a cured product obtained by curing a curable composition containing a urethane (meth) acrylate oligomer in advance with active energy rays is manufactured, surface processing, etc. Is applied at room temperature or under heating conditions, and in this case, the cured product is required to have stretchability after curing to follow deformation during three-dimensional processing.

  Patent document 1 discloses urethane, which is a reactant of polyisocyanate, a diol having an alicyclic structure, and a hydroxyalkyl (meth) acrylate, as one having such stretchability and excellent stain resistance. Curable compositions of acrylate oligomers are disclosed.

  Patent Document 2 describes an active energy containing a diisocyanate compound, a diol compound having 1 to 5 carbon atoms, and a monohydroxy compound having a polymerizable functional group, as having good surface hardness and flexibility. Linear curable oligomers are disclosed.

JP, 2010-222568, A JP, 2011-042770, A

According to the detailed study of the present inventors, in the case of the curable composition described in Patent Document 1, particularly, the abrasion resistance is insufficient, and the coating film appearance, the abrasion resistance, and the contamination resistance It has been found that a curable composition which is sufficiently excellent in stretchability after curing and stain resistance after stretching has not been obtained. Moreover, in the active energy ray-curable oligomer described in Patent Document 2, although it has hardness and flexibility showing a degree of good bending resistance, it has stretchability that can follow deformation during three-dimensional processing. Was found to be insufficient. That is, the subject of the present invention is excellent in the appearance of a coated film after curing, there is no tackiness at the time of non-curing, and the handling property is good, and the abrasion resistance, the staining resistance after curing and after curing / stretching Urethane (meth) acrylate oligomers which are excellent and which are also excellent in stretchability after curing to follow deformation of three-dimensional processing, and curable products and laminates using the same and curable compositions using the same, And providing a method for producing a cured film .

The inventors of the present invention conducted intensive studies to solve the above problems, and as a result, a urethane (meth) acrylate oligomer obtained using a specific raw material, and a curable composition containing the same and an organic solvent are as described above. It has been found that the problem can be solved, and the present invention has been achieved. That is, the gist of the present invention resides in the following [1] to [10].

[1]
It is obtained by reacting at least the following compound (A), compound (B) and compound (C), and the urethane bond amount is 5.2 × 10 ^{−3 to} 10.0 × 10 ⁻³ eq / g, (meth) acryloylyl A composition comprising a urethane (meth) acrylate oligomer having a basis weight of 0.8 × 10 ^{−3 to} 3.0 × 10 ⁻³ eq / g and an organic solvent, and the content of the urethane (meth) acrylate oligomer being curable The curable composition which is 60 weight% or more with respect to the total of all the components except the organic solvent in it .
Compound (A): Polyisocyanate Compound (B): Linear aliphatic diol compound having 2 to 5 carbon atoms (C): Polyfunctional (meth) acrylate having a hydroxyl group

[2] The curable composition according to [1], wherein the weight average molecular weight (Mw) of the urethane (meth) acrylate oligomer is 1,500 to 30,000.

[3] The curable composition according to [1] or [2], which contains at least ethylene glycol as the compound (B).

[4] The urethane (meth) acrylate oligomer is obtained by reacting the compound (A) and the compound (B) to obtain a urethane prepolymer and then reacting the compound (C) with the urethane prepolymer. The curable composition according to any one of [1] to [3].

[5] The curable composition according to any one of [ 1] to [4], wherein the solubility parameter of the organic solvent is 8.0 to 11.5.

[6] The curable composition according to [ 1] to [5] , which has a solid content concentration of 5 to 90% by weight.

[7] A cured product obtained by irradiating the curable composition according to any one of [ 1] to [6] with an active energy ray.

[8] A laminate obtained by applying the curable composition according to any one of [ 1 ] to [ 6 ] on a substrate, and curing the composition by irradiating it with active energy rays.

[9] A step of applying the curable composition according to any one of [ 1] to [6] onto a substrate, a step of irradiating the curable composition with an active energy ray to obtain a cured product, A method for producing a cured film, which comprises the step of stretching the cured product.

[10] A step of applying the curable composition according to [6] or [7] onto a substrate, a step of irradiating the curable composition with an active energy ray to obtain a cured product, and stretching the cured product A method of producing a cured film, comprising the steps of:

According to the present invention, the appearance of the coated film after curing is excellent, there is no tackiness when it is not cured, the handling property is good, and the abrasion resistance, and the contamination resistance after curing and after curing and stretching are excellent. There are provided a urethane (meth) acrylate oligomer excellent also in the stretchability after curing for following the deformation of three-dimensional processing, and a curable composition using the same. Further, according to the present invention, a cured product, a laminate, and a method for producing a cured film using the urethane (meth) acrylate oligomer and the curable composition are provided.

Hereinafter, the embodiments of the present invention will be described in detail, but the following description is a representative example of the embodiments of the present invention, and the present invention is not limited to these contents. In the present invention, “(meth) acrylate” is a generic name of acrylate and methacrylate, and means either or both of acrylate and methacrylate, and “(meth) acryloyl” and “(meth) acrylic” The same is true. Moreover, in this invention, "-" is used in the meaning which includes the numerical value described before and after that as a lower limit and an upper limit.

[Urethane (meth) acrylate oligomer]
The urethane (meth) acrylate oligomer of the present invention is obtained by reacting at least the following compound (A), compound (B) and compound (C), and the urethane bond amount is 5.2 × 10 ^{−3 to} 10.0 × The amount of (meth) acryloyl group is 10 ^-3 eq / g and the amount of the (meth) acryloyl group is 0.8 × 10 ^{-3 to} 3.0 × 10 ^-3 eq / g.
Compound (A): Polyisocyanate Compound (B): Linear aliphatic diol compound having 2 to 5 carbon atoms (C): Polyfunctional (meth) acrylate having a hydroxyl group

  The urethane (meth) acrylate oligomer of the present invention and the curable composition of the present invention to be described later have no coating appearance after curing, no tackiness when uncured, and excellent handleability, and abrasion resistance, after curing and It has excellent stain resistance after curing and drawing, and stretchability after curing that can follow deformation during three-dimensional processing. In particular, the stretchability which is remarkably superior in handling property as compared with the curable compositions described in the above-mentioned Patent Documents 1 and 2 and which can follow the deformation at the time of three-dimensional processing is described in the above-mentioned Patent Document 2 It is significantly superior to the curable composition.

  The reason why the curable composition of the present invention exhibits the above-mentioned excellent effects is not clear, but the handling property is considered to be due to the following reasons. That is, the urethane (meth) acrylate oligomer of the present invention can be obtained by using a chain aliphatic diol having a short chain length (a chain aliphatic diol having 2 to 5 carbon atoms) as the compound (B) used as a raw material. It is considered that the distance between urethane bonds in the above becomes short, strong hydrogen bonds derived from urethane bonds are formed between molecules, and the hardness and rigidity of the uncured coating film are obtained. Although the same hydrogen bond is formed even with the urethane (meth) acrylate oligomers described in the above-mentioned Patent Documents 1 and 2, it is presumed that the hardness and the rigidity obtained are insufficient because the amount of the urethane bond is small. Ru.

  With regard to the stretchability after curing, it is considered that hydrogen bonds are relaxed at high temperature, and the stretchability (elongation of the cured product) is dominated by the crosslink density among (meth) acryloyl groups. The urethane (meth) acrylate oligomer described in Patent Document 2 is considered to be insufficient in stretchability because the amount of (meth) acryloyl group is higher than that of the urethane (meth) acrylate oligomer of the present invention.

  Furthermore, as for the contamination resistance after curing, the crosslinkability between molecules when curing the urethane (meth) acrylate oligomer is enhanced by the component (C) having a plurality of (meth) acryloyl groups, and the molecule It is thought that this is caused by the network becoming more robust. In particular, with regard to the contamination resistance after curing and drawing, the urethane bond relaxed by heating at the time of the drawing process is removed when the amount of urethane bond of the urethane (meth) acrylate oligomer of the present invention is high. It is presumed to be due to being reassembled into an ordered intermolecular network.

[Compound (A)]
The compound (A) used in the present invention is a polyisocyanate. The polyisocyanate is a compound having a total of two or more substituents containing an isocyanate group and / or an isocyanate group in one molecule. As the compound (A), one type may be used, or two or more types may be used. In the present invention, isocyanate groups and substituents containing isocyanate groups are collectively referred to as “
It may be called "isocyanate groups". In the compound (A), the isocyanate groups may be the same or different.

  As a substituent containing an isocyanate group, a C1-C5 alkyl group, a C1-C5 alkenyl group, or a C1-C5 alkoxyl group containing one or more isocyanate groups is mentioned, for example. Among these, a C1-C5 alkyl group is preferable, and especially a C1-C3 alkyl group is preferable.

  The type of the polyisocyanate is not particularly limited, and examples thereof include linear aliphatic polyisocyanates, aromatic polyisocyanates, alicyclic polyisocyanates, and the like, and even if one of these is used, a combination of two or more is used. You may use it. Among these, as the component (A), from the viewpoint of enhancing the weather resistance and hardness of the obtained cured product, it is preferable to contain an alicyclic polyisocyanate.

  The linear aliphatic polyisocyanate is a compound having a linear aliphatic structure and two or more isocyanate groups bonded thereto. The linear 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 linear aliphatic structure in the linear aliphatic polyisocyanate is not particularly limited, but is preferably a linear or branched alkylene group having 1 to 6 carbon atoms. Examples of such linear aliphatic polyisocyanates include aliphatic diisocyanates such as tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, dimer acid diisocyanate, and aliphatic tris such as tris (isocyanatohexyl) isocyanurate. And isocyanates. These may be used alone or in combination of two or more.

  The aromatic polyisocyanate is a compound having an aromatic structure and two or more isocyanate groups bonded thereto. The aromatic structure in 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. The aromatic polyisocyanate is preferable from the viewpoint of enhancing the mechanical strength of the cured film obtained by curing the curable composition, and examples of such aromatic polyisocyanate include tolylene diisocyanate and diphenylmethane diisocyanate. These may be used alone or in combination of two or more.

  Alicyclic polyisocyanate is a compound having an alicyclic structure and two or more isocyanate groups. Although the alicyclic structure in a compound (A) is not specifically limited, It is preferable that it is C5-C15, and it is more preferable that it is C6 or more. The carbon number is more preferably 14 or less, and particularly preferably 13 or less. Furthermore, as an alicyclic structure, a cycloalkylene group is preferable. Examples of polyisocyanates having an alicyclic structure include bis (isocyanatomethyl) cyclohexane, cyclohexane diisocyanate, bis (isocyanate cyclohexyl) methane, diisocyanates having an alicyclic structure such as isophorone diisocyanate, and tris (isocyanate isophorone) isocyanurate And triisocyanates having an alicyclic structure of Among these, it is preferable to contain isophorone diisocyanate.

[Compound (B)]
The compound (B) used in the present invention is a C2-C5 linear aliphatic diol. The chain structure in compound (B) may be linear or branched.

  As compound (B), for example, ethylene glycol, propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 1,2-butanediol, 1,3-butanediol, 1, 4- butanediol, 2, 3- butanediol, 1, 2- pentanediol, 1, 5- pentanediol etc. are mentioned. Among these, containing at least one of ethylene glycol and 1,4-butanediol can provide a curable composition excellent in stain resistance after curing, abrasion resistance, and handling property before curing. Among these, ethylene glycol is particularly preferred.

  In the present invention, the compound (B) is used in an amount of 40% by weight or more based on the total diol component used as a raw material of the urethane (meth) acrylate oligomer. From the viewpoint of improving the handling of Further, in order to further enhance this effect, the content of the compound (B) is more preferably 60% by weight or more, still more preferably 80% by weight or more, and particularly preferably 90% by weight or more. Is usually 100% by weight.

[Compound (C)]
The polyfunctional (meth) acrylate having a hydroxyl group of the compound (C) used in the present invention is a compound having one or more hydroxyl groups, two or more (meth) acryloyl groups and a hydrocarbon group. A polyfunctional (meth) acrylate having a hydroxyl group forms a good crosslinked structure by involving a plurality of (meth) acryloyl groups in a curing reaction when obtaining a cured film, and physical properties such as stain resistance and abrasion resistance Can be made good.

  As the compound (C), for example, bisphenol A diglycidyl ether diacrylate, 1,4-cyclohexane dimethanol diglycidyl ether diacrylate, ethylene glycol diglycidyl ether diacrylate, 1,4-butanediol diglycidyl ether diacrylate, 1,6-hexanediol diglycidyl ether diacrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate and the like.

  Among these, an alkylene group having 2 to 4 carbon atoms between a (meth) acryloyl group such as pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate and dipentaerythritol penta (meth) acrylate and a hydroxyl group Particularly preferred in view of the mechanical strength of the resulting cured film is a hydroxyalkyl poly (meth) acrylate having

  The molecular weight of the compound (C) is preferably 100 or more, and more preferably 200 or more. On the other hand, the molecular weight of the compound (C) is preferably 800 or less, more preferably 500 or less, from the viewpoint of the mechanical strength of the resulting cured film. In addition, when a compound (C) is said addition reaction substance or polymer, the said molecular weight means the number average molecular weight by gel permeation chromatography measurement (GPC measurement).

[Other raw material compounds]
In the raw material compounds of the urethane (meth) acrylate oligomer of the present invention, other raw material compounds other than the compound (A), the compound (B) and the compound (C) may be used within the range not significantly inhibiting the effects of the present invention. Good. As such other raw material compounds, for example, a chain aliphatic diol having 6 to 16 carbon atoms, a diol having an alicyclic structure, a polyalkylene glycol, a high molecular weight polyol other than these (hereinafter, “other high molecular weight These are referred to as "polyols"), hydroxyalkyl mono (meth) acrylates, chain extenders and the like.

  Examples of linear aliphatic diols having 6 to 16 carbon atoms include 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9. Nonanediol, 1-10 decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,14-tetracandiol, 1,16-hexadecanediol, 2,2,4-trimethyl-1,3 -Pentanediol, 2-methyl-1, 8-octanediol, etc. are mentioned. These may be used alone or in combination of two or more.

  Examples of the diol having an alicyclic structure include 1,4-cyclohexanedimethanol, hydrogenated bisphenol A and the like. These may be used alone or in combination of two or more.

  Examples of polyalkylene glycols include polyethylene glycol, polypropylene glycol, polytrimethylene glycol, polytetramethylene glycol and the like. These may be used alone or in combination of two or more.

  Examples of other high molecular weight polyols include polyether diols, polyester diols, polyether ester diols, polyolefin polyols, and silicone polyols. These may be used alone or in combination of two or more.

  As hydroxyalkyl mono (meth) acrylate, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, cyclohexane di Addition reaction product of methanol mono (meth) acrylate, 2-hydroxyethyl (meth) acrylate and caprolactone, addition reaction product of 4-hydroxybutyl (meth) acrylate and caprolactone, addition of glycidyl ether and (meth) acrylic acid Reactants, mono (meth) acrylates of glycols, etc. may be mentioned. Among these, the number of carbon atoms is 2 to 4 between the (meth) acryloyl group such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, etc. and the hydroxyl group The hydroxyalkyl mono (meth) acrylate which has the alkylene group of is preferable from the viewpoint of the mechanical strength of the cured film obtained. These may be used alone or in combination of two or more.

  A chain extender is a compound having two or more active hydrogens that react with isocyanate groups. Examples of chain extenders include low molecular weight diamine compounds having a number average molecular weight of less than 500, and the like, and, for example, aroma such as 2,4- or 2,6-tolylenediamine, xylylenediamine, 4,4'-diphenylmethanediamine, etc. Ethylenediamine, 1,2-propylenediamine, 1,6-hexanediamine, 2,2-dimethyl-1,3-propanediamine, 2-methyl-1,5-pentanediamine, 2,2,4- or Aliphatic diamines such as 2,4,4-trimethylhexanediamine, 2-butyl-2-ethyl-1,5-pentanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine; And 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, 4,4'-dicyclohexylmethane Amine, isopropylidene cyclohexyl-4,4'-diamine, 1,4-diaminocyclohexane, 1,3-bis-aminomethyl cyclohexane, alicyclic diamines such as tricyclodecane diamine. One of these may be used, or two or more may be used in combination.

[Physical properties of urethane (meth) acrylate oligomer]
The urethane bond amount of the urethane (meth) acrylate oligomer is 5.2 × 10 ^{−3 to} 10.0 × 10 ⁻³ eq / g. The contamination resistance of the cured film and the handling property of the uncured film are improved when the amount of urethane bond is 5.2 × 10 ⁻³ or more, and the solution stability is 10.0 × 10 ⁻³ eq / g or less. Handleability is improved. Further, from the viewpoint of making these effects better, the urethane bond amount of the urethane (meth) acrylate oligomer is preferably 5.3 × 10 ⁻³ eq / g or more, and 5.5 × 10 ⁻ It is more preferably ³ eq / g or more, still more preferably 5.8 × 10 ⁻³ eq / g or more, and on the other hand, 9.0 × 10 ⁻³ eq / g or less, 8 It is more preferable that it is not more than 0 × 10 ⁻³ eq / g. In addition, said urethane bond amount can be controlled by adjusting the raw material mixture of a urethane (meth) acrylate oligomer.

  Further, in the present invention, the above urethane bond amount is calculated as follows. The urethane (meth) acrylate oligomer of the present invention is at least a polyisocyanate of compound (A), a linear aliphatic diol having 2 to 5 carbon atoms of compound (B), and a polyfunctional (meth) having a hydroxyl group of compound (C) An acrylate is used as a raw material, and it can be considered that the structural unit in the urethane (meth) acrylate oligomer obtained is that the raw material composition used is maintained as it is. From this, the total equivalent number of urethane bond number (isocyanate group (total value obtained by multiplying the number of moles of polyisocyanate by the number of moles of polyisocyanate group)) and total functional group reacting with isocyanate groups such as hydroxyl group and amino group The smaller one of the total equivalent number and the total equivalent number of the urethane (meth) acrylate oligomer is divided by the total amount of the components of the urethane (meth) acrylate oligomer (the total amount of each raw material component excluding the amount of the component added in excess). Calculated.

The (meth) acryloyl group content of the urethane (meth) acrylate oligomer is 0.8 × 10 ^{−3 to} 3.0 × 10 ⁻³ eq / g. When the (meth) acryloyl group content is 0.8 × 10 ⁻³ eq / g or more, the contamination resistance and abrasion resistance after curing improve, and when it is 3.0 × 10 ⁻³ eq / g or less, 3 Stretchability after curing that can follow deformation during dimensional processing is improved. Also, from the viewpoint of making these effects better, the amount of (meth) acryloyl group of the urethane (meth) acrylate oligomer is preferably 0.9 × 10 ⁻³ eq / g or more, 1.0 It is more preferable that it is ^10-3 eq / g or more, and it is preferable that it is 2.7 ^10-3 eq / g or less, and it is more preferable that it is 2.5 ^10-3 eq / g or less. preferable. In addition, said (meth) acryloyl group content can be controlled by adjusting the raw material combination of a urethane (meth) acrylate oligomer.

  Further, in the present invention, the amount of (meth) acryloyl group is calculated as follows. The urethane (meth) acrylate oligomer of the present invention is at least a polyisocyanate of compound (A), a linear aliphatic diol having 2 to 5 carbon atoms of compound (B), and a polyfunctional (meth) having a hydroxyl group of compound (C) An acrylate is used as a raw material, and it can be considered that the structural unit in the urethane (meth) acrylate oligomer obtained is that the raw material composition used is maintained as it is. From this, the number of (meth) acryloyl groups (total value of the number of moles of polyfunctional (meth) acrylates having hydroxyl groups excluding the amount of components added in excess times the number of (meth) acryloyl functional groups) is urethane It is calculated by dividing by the total amount of components of the (meth) acrylate oligomer (the total amount of each of the raw material components excluding the amount of the component added in excess) (not the preparation amount).

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 30,000
It is preferably the following, more preferably 19,000 or less, and still more preferably 8,000 or less. If the weight average molecular weight of the urethane (meth) acrylate oligomer is equal to or more than the above lower limit value, the three-dimensional processability of the resulting cured film tends to be favorable. When the number average molecular weight of the urethane (meth) acrylate oligomer is less than or equal to the above upper limit value,
The stain resistance of a 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 crosslinking points in the network structure and the three-dimensional processability and the stain resistance of the cured film obtained therefrom, and the smaller the weight average molecular weight, the crosslinking point The distance between them is short, and the distance between the crosslinking points tends to be longer as the weight average molecular weight is larger. The reason that the weight average molecular weight affects the three-dimensional processing suitability and the stain resistance is that the longer the distance between the crosslinking points, the softer and easier to stretch structure becomes, and the three-dimensional processing aptitude becomes better. It is estimated that the scratch resistance, the stain resistance and the wear resistance become better. 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 Examples described later.

[Method for producing urethane (meth) acrylate oligomer]
The urethane (meth) acrylate oligomer of the present invention can be produced by subjecting the compound (B) and the compound (C) to an addition reaction with the compound (A). In addition, the preparation 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.

These addition reactions can be performed using any of the known methods for producing urethane (meth) acrylate oligomers. Examples of such a method include the following methods (1) to (3).
(1) The compound (A) and the compound (B) are reacted under conditions such that the isocyanate group is excessive to obtain an isocyanate-terminated urethane prepolymer, and then the isocyanate-terminated urethane prepolymer And the compound (C). (2) A method in which all the raw material compounds are simultaneously added at once and reacted.
(3) The compound (A) and the compound (C) are reacted first to obtain a urethane (meth) acrylate prepolymer having a (meth) acryloyl group and an isocyanate group simultaneously in the molecule, which is obtained A method of reacting the compound (B) with the prepared prepolymer.

  Among these, according to the method (1), the urethane prepolymer is obtained by subjecting the compound (A) and the compound (B) to a urethanization reaction. The target urethane (meth) acrylate oligomer has a structure formed by causing a urethane prepolymer having an isocyanate group at an end to react with the compound (C). According to the method of (1), it is preferable because control of molecular weight is easy and a (meth) acryloyl group can be introduced to both ends and a cured film can be easily obtained.

  The amount of all isocyanate groups in the urethane (meth) acrylate oligomer and the amount of all functional groups that react with isocyanate groups such as hydroxyl and amino groups are usually theoretically equimolar. Therefore, the amounts of compound (A), compound (B), compound (C) and other raw material compounds used as raw materials are the amount of all isocyanate groups in the urethane (meth) acrylate oligomer and all functional groups that react therewith. The amount is an amount equivalent to 50 to 200 equivalent% in equivalent equivalents or equivalent% of the total functional group with respect to the isocyanate group.

  When producing a urethane (meth) acrylate oligomer, the amount of compound (C) used is 3 moles with respect to the total amount of compounds (C) and compounds containing functional groups that react with isocyanate groups in other raw materials % Or more is preferable, 5 mol% or more is more preferable, 70 mol% or less is preferable, 50 mol% or less is more preferable, and 30 mol% or less is particularly preferable. By this ratio, the molecular weight of the resulting urethane (meth) acrylate oligomer can be controlled. When the proportion of the compound (C) 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.

  Furthermore, when a chain extender is used, all polyols of the compound (B), the diol component other than the compound (B), and other polyol components (compounds having two or more alcoholic hydroxyl groups) and the chain extender The amount of the total polyol used is preferably 70 mol% or more, more preferably 80 mol% or more, and still more preferably 90 mol% or more based on the total amount of the combined compounds. It is particularly preferable to use 95 mol% or more. When the total amount of polyols is equal to or more than the above lower limit value, the liquid stability tends to be improved.

  In addition, said use raw material ratio becomes a standard at the time of manufacturing a urethane (meth) acrylate oligomer. In practice, 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 the urethane (meth) acrylate oligomer, an organic solvent can be used for the purpose of adjusting the viscosity. An organic solvent may be used individually by 1 type, and may mix and use 2 or more types. As the organic solvent, any of known organic solvents 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, and methyl isobutyl ketone, N-methyl pyrrolidone, dimethylformamide and the like. The organic solvent can be used usually in an amount of 300 parts by weight or less based on 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 the 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. It is more preferable that The upper limit of the total content is usually 100% by weight. When the total content of the urethane (meth) acrylate oligomer and the raw material compound thereof is equal to or more than the above lower limit value, the reaction rate becomes 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- Bismuth-based catalysts such as ethyl hexanate 9, etc. may be used alone, or two or more of them may be used as a mixture. Bismuth tris (2-ethylhexanate) is preferable from the viewpoint of environmental adaptability, catalytic activity, storage stability, etc. The amount of the catalyst used is usually 2 at the upper limit with respect to the total content of the raw material compounds. 1,000 ppm or less, preferably 1,000 ppm or less, and the lower limit is usually 10 ppm or more, preferably 30 ppm or more In addition, when it manufactures by the method of said (1), the said compound (A) and the compound (B) are made to react especially, the reaction which obtains a urethane prepolymer, and said compound (C) with respect to a urethane prepolymer. It is preferable to use the above-mentioned catalyst in both reactions in addition reaction of.

Moreover, when using the compound which contains a (meth) acryloyl group like a compound (C) in a reaction system at the time of manufacture of a urethane (meth) acrylate oligomer, it is preferable to use a polymerization inhibitor together. Examples of such polymerization inhibitors include phenols such as hydroquinone, methyl hydroquinone, hydroquinone monoethyl ether and dibutyl hydroxytoluene, amines such as phenothiazine and diphenylamine, copper salts such as copper dibutyldithiocarbamate, manganese acetate and the like Manganese salts, nitro compounds, nitroso compounds and the like can be mentioned. The polymerization inhibitors may be used alone or in combination of two or more. Among these, phenols are preferable as the polymerization inhibitor. The upper limit of the amount of polymerization inhibitor used is usually 3,000 ppm or less, preferably 1,000 pp, based on the total content of the raw material compounds.
It is m or less, particularly preferably 500 ppm or less, while the lower limit is usually 50 ppm or more, preferably 100 ppm or more.

  In the production of the urethane (meth) acrylate oligomer, the reaction temperature is preferably 20 ° C. or more, preferably 40 ° C. or more, and more preferably 60 ° C. or more. When the reaction temperature is equal to or higher than the above lower limit, the reaction rate is increased, and the production efficiency tends to be improved. Moreover, it is preferable that reaction temperature is 120 degrees C or less, and it is more preferable that it is 100 degrees C or less. It is preferable for the reaction temperature to be equal to or lower than the above upper limit because side reactions such as the alohanatization reaction are less likely to occur. 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 (C) is contained (meta It is preferable that the temperature is 70 ° C. or less from the viewpoint of preventing excessive reaction of the acryloyl group. The reaction time is usually 5 to 20 hours.

[Curable composition]
The curable composition of the present invention comprises 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 dissolved well, and as described later, when the urethane (meth) acrylate oligomer is irradiated with an active energy ray to be cured, the viscosity for forming a coating film And a uniform cured film can be obtained.

  As the organic solvent, any known organic solvent can be used as long as the effects of the present invention can be obtained. Preferably, the solubility parameter (hereinafter referred to as “SP value”) is an organic solvent having a value of 8.0 to 11.5. It is preferable from the viewpoint of the solubility of the urethane (meth) acrylate oligomer that the SP value is 8 or more, and it is preferable from the viewpoint of the transparency of the solution that the SP value is 11.5 or less. As the organic solvent in the above range, for example, toluene (SP value: 9.1), xylene (SP value: 9.1), ethyl acetate (SP value: 8.7), butyl acetate (SP value: 8.7) ), Cyclohexanone (SP value: 9.8), methyl ethyl ketone (SP value: 9.0), and methyl isobutyl ketone (SP value: 8.7), N-methylpyrrolidone (SP value: 11.2), etc. Be 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 147-154)". Further, the SP value is a physical property value determined by the content of a hydrophobic group or a hydrophilic group of a molecule, and when using a mixed solvent, it means a value as a mixture.

  The organic solvent can be used usually at a solid content concentration of 5 to 90% by weight of the curable composition, 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% by weight or less, and still more preferably 60% by weight or less. The term "solid content" as used herein means not only urethane acrylate (meth) acrylate oligomers but also all components excluding solvents, not only solid ones but also semi-solid and viscous liquids. Shall be included.

<Other ingredients>
The curable composition of the present invention may be further referred to as components other than the urethane (meth) acrylate oligomer and the organic solvent (in the present invention, "other components", to the extent that the effects of the present invention are not significantly impaired. May be contained. Other components include, for example, active energy ray reactive monomers, active energy ray curable oligomers (except for the urethane (meth) acrylate oligomer of the present invention), polymerization initiators, photosensitizers, epoxy compounds and others. An additive etc. are mentioned.

  In the curable composition of the present invention, the content of the urethane (meth) acrylate oligomer is 40% by weight or more based on the total amount of all the components except the solvent in the curable composition, such as the active energy ray reactive component. Is preferably 60% by weight or more. When the content of the urethane (meth) acrylate oligomer is at least the above lower limit, the curability is good, and the three-dimensional processability tends to be improved without excessively increasing the mechanical strength when forming a cured film. Because it is preferable. The upper limit of the content of the urethane (meth) acrylate oligomer is 100% by weight.

  In addition, in the curable composition of the present invention, the total content of the reactive energy ray reactive component including the urethane (meth) acrylate oligomer is excellent in the curing speed and surface curability as the composition, and the tack does not remain, etc. 60% by weight or more, more preferably 80% by weight or more, still more 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 effects of the present invention can be obtained. These active energy ray reactive monomers are used for the purpose of adjusting the hydrophilicity and hydrophobicity of the urethane (meth) acrylate oligomer, and the physical properties such as hardness and elongation of the cured film when the resulting composition is a cured film. Ru. The active energy ray-reactive monomer may be used alone or in combination of two or more.

Such active energy ray reactive monomers include, for example, vinyl ethers, (meth) acrylamides, and (meth) acrylates. Specifically, for example, styrene, α-methylstyrene, α-chlorostyrene Vinyl monomers such as vinyl toluene and divinyl benzene; vinyl acetate, vinyl butyrate, N-vinylformamide, N-vinylacetamide, N-vinyl-2-pyrrolidone, N-vinylcaprolactam, vinyl adipate and the like Ester monomers; vinyl ethers such as ethyl vinyl ether and phenyl vinyl ether; allyl compounds such as diallyl phthalate, trimethylolpropane diallyl ether and allyl glycidyl ether; (meth) acrylamide, N, N-dimethyl acrylamide N, N-dimethyl methacrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, N-t-butyl (meth) acrylamide, (meth) acryloyl morpholine (Meth) acrylamides such as methylene bis (meth) acrylamide; (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, n-butyl (meth) acrylate -(Meth) acrylic acid-i-butyl, (meth) acrylic acid-t-butyl, (meth) acrylic acid hexyl, (meth) acrylic acid 2-ethylhexyl, (meth) acrylic acid lauryl, (meth) acrylic acid Stearyl, tetrahydrofurfuryl (meth) acrylate, (meth) acid Morphyl lyllate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, glycidyl (meth) acrylate, dimethyl (meth) acrylate Aminoethyl, diethylaminoethyl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, tricyclodecane (meth) acrylate, dicyclopentenyl (meth) acrylate , (Meth) acrylic acid dicyclopentenyl oxyethyl, (meth) acrylic acid dicyclopentanyl, allyl (meth) acrylic acid, (meth) acrylic acid 2-ethoxyethyl (meth) acrylic acid, (meth) acrylic acid isobornyl (meth) Monofunctional (Meth) acres such as phenyl acrylate And ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate n = 5 to 14), propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, di (meth) Acrylic acid polypropylene glycol (n = 5 to 14), di (meth) acrylic acid-1,3-butylene glycol, di (meth) acrylic acid-1,4-butanediol, di (meth) acrylic acid polybutylene glycol n = 3 to 16), di (meth) acrylic acid ester (1-methyl butylene glycol) (n = 5 to 20), di (meth) acrylic acid 1, 6-hexanediol, di (meth) acrylic acid 1, 9-nonane diol, di (meth) acrylic acid Neopentyl glycol, hydroxypivalic acid neopentyl glycol di (meth) acrylic acid ester, di (meth) acrylic acid dicyclopentanediol, di (meth) acrylic acid tricyclodecane, bisphenol A diglycidyl ether diacrylate, 1,4 -Cyclohexanedimethanol diglycidyl ether diacrylate, ethylene glycol diglycidyl ether diacrylate, 1,4-butanediol diglycidyl ether diacrylate, 1,6-hexanediol diglycidyl ether diacrylate, trimethylolpropane triol Meta) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol Hexa (meth) acrylate, trimethylolpropane trioxyethyl (meth) acrylate, trimethylolpropane trioxypropyl (meth) acrylate, trimethylolpropane polyoxyethyl (meth) acrylate, trimethylolpropane polyoxypropyl (meth) acrylate, Tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (2-hydroxyethyl) i Cyanurate 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, propylene oxide added bisphenol F di (meth) acrylate, Polyfunctional (meth) acrylates such as tricyclodecanedimethanol di (meth) acrylate, bisphenol A epoxy di (meth) acrylate, and bisphenol F epoxy di (meth) acrylate.

Among these, in particular, in applications where coating properties of the composition of the present invention are required, (meth) acryloyl morpholine, tetrahydrofurfuryl (meth) acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate , Molecules such as trimethylcyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, tricyclodecane (meth) acrylate, dicyclopentenyl (meth) acrylate, isobornyl (meth) acrylate, (meth) acrylamide, etc. Monofunctional (meth) acrylates having a ring structure in the inside are preferable, and on the other hand, in applications where the mechanical strength of the resulting cured film is required, di (meth) acrylic acid-1,4-butanediol, ) Acrylic acid 1,6-hexanediol, di (meth) acrylic acid 1,9-nonanedi , Neopentyl glycol di (meth) acrylate, tricyclodecane di (meth) acrylate, 1,4-cyclohexanedimethanol diglycidyl ether diacrylate, ethylene glycol diglycidyl ether diacrylate, 1,4-butanediol Diglycidyl ether diacrylate, 1,6-hexanediol diglycidyl ether diacrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol tetra (meth) Preferred are polyfunctional (meth) acrylates such as acrylate, dipentaerythritol penta (meth) acrylate and dipentaerythritol hexa (meth) acrylate. In applications where stretchability of the cured film is required, polyethylene glycol di (meth) acrylate (n = 5 to 14), polypropylene glycol di (meth) acrylate (n = 5 to 14), di (meth) acrylic acid Polyether (meth) acrylates such as polybutylene glycol (n = 3 to 16) and di (meth) acrylic acid poly (1-methyl butylene glycol) (n = 5 to 20) are preferred.

  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 physical properties such as hardness and elongation of the obtained cured film. The content is preferably 50% by weight or less, more preferably 30% by weight or less, still more preferably 20% by weight or less, and still more preferably 10% by weight or less.

  The active energy ray curable oligomers may be used alone or in combination of two or more. As the active energy ray-curable oligomers, epoxy (meth) acrylate oligomers, and acrylic (meth) acrylate oligomers, polyester (meth) acrylate oligomers, polycarbonate (meth) acrylate oligomers, polybutadiene (meth) acrylate oligomers And polyether (meth) acrylates (except those described in the above-mentioned active energy ray reactive monomer). 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 resulting cured film. Is more preferably 30% by weight or less, still more preferably 20% by weight or less, and particularly preferably 10% by weight or less.

  The said polymerization initiator is mainly used for the purpose of improving the start efficiency of the polymerization reaction which advances with irradiation of active energy rays, such as an ultraviolet-ray and an electron beam. As the polymerization initiator, a photo radical polymerization initiator which is a compound having a property of generating radicals by light is generally used, and any known radical photo polymerization initiator can be used as long as the effects of the present invention can be obtained. It is. The polymerization initiators may be used alone or in combination of two or more. Furthermore, a photo radical polymerization initiator and a photosensitizer may be used in combination.

  As a radical photopolymerization initiator, for example, benzophenone, 2,4,6-trimethyl benzophenone, 4,4-bis (diethylamino) benzophenone, 4-phenyl benzophenone, methyl ortho benzoyl benzoate, thioxanthone, diethyl thioxanthone, isopropyl thioxanthone, chloro Thioxanthone, 2-ethylanthraquinone, t-butylanthraquinone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyl dimethyl ketal, 1-hydroxycyclohexyl phenyl ketone, benzoin methyl ether, benzoin ethyl Ether, benzoin isopropyl ether, benzoin isobutyl ether, methyl benzoyl formate, 2-methyl-1- [4- ( [Cylthio) phenyl] -2-morpholinopropan-1-one, 2,6-dimethylbenzoyldiphenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4, 4-trimethylpentyl phosphine oxide, bis (2,4,6-trimethylbenzoyl) phenyl phosphine oxide, and 2-hydroxy-1- [4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl]- Phenyl] -2-methyl-propan-1-one and the like.

Among these, benzophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2,4, 6 in that the curing rate is fast 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-hydroxycyclohexyl phenyl ketone, 2,4,6-trimethyl benzoyl diphenyl phosphine oxide, and 2-hydroxy-1- [4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] -phenyl ] -2-Methyl-propan-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 cationic light polymerization initiator is included as a polymerization initiator together with the above radicalized radical polymerization initiator. It may be done. As the photo cationic polymerization initiator, any known one can be used as long as the effects of the present invention are not significantly inhibited.

  The content of these polymerization initiators in the curable composition of the present invention is preferably 10 parts by weight or less, and 5 parts by weight or less, based on 100 parts by weight of the total of the active energy ray reactive components. It is more preferable that When the content of the photopolymerization initiator is less than or equal to the above upper limit value, it is preferable because the degradation of mechanical strength due to the initiator decomposition product hardly occurs.

  The photosensitizer can be used for the same purpose as the polymerization initiator. A photosensitizer may be used individually by 1 type, and may mix and use 2 or more types. As a photosensitizer, any of known photosensitizers can be used as long as the effects of the present invention can be obtained. As such photosensitizers, for example, ethanolamine, diethanolamine, triethanolamine, N-methyldiethanolamine, methyl 4-dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, amyl 4-dimethylaminobenzoate, And 4-dimethylaminoacetophenone and the like.

  In the curable composition of the present invention, the content of the photosensitizer is preferably 10 parts by weight or less, and 5 parts by weight or less, based on 100 parts by weight of the total of the active energy ray reactive components. It is more preferable that When the content of the photosensitizer is less than or equal to the above upper limit value, the reduction of the crosslink density is less likely to occur, which is preferable.

  The said additive is arbitrary in the range from which the effect of this invention is acquired, and the various material added to the composition used for the same use can be used as an additive. An additive may be used individually by 1 type, and may mix and use 2 or more types. As such additives, for example, glass fiber, glass bead, silica, alumina, calcium carbonate, mica, zinc oxide, titanium oxide, mica, talc, kaolin, metal oxide, metal fiber, iron, lead, metal powder Fillers, etc .; Carbon materials such as carbon fibers, carbon black, graphite, carbon nanotubes, fullerenes such as C60 (fillers, carbon materials may be collectively referred to as "inorganic component"); Agents, heat stabilizers, UV absorbers, hindered amine light stabilizers (HALS), anti-fingerprint agents, surface hydrophilizing agents, antistatic agents, slip agents, plasticizers, mold release agents, antifoam agents, leveling agents, Modifiers such as anti-settling agent, surfactant, thixotropy-imparting agent, lubricant, flame retardant, flame retardant aid, polymerization inhibitor, filler, silane coupling agent, etc .; pigment, dye, hue adjustment Colorants and the like; and, monomer and / or oligomer thereof, or a curing agent required for the synthesis of inorganic components, catalysts, curing accelerators like; and the like.

  In the curable composition of the present invention, the content of the additive is preferably 10 parts by weight or less and 5 parts by weight or less based on 100 parts by weight of the total of the active energy ray reactive components. Is more preferred. When the content of the additive is less than or equal to the above upper limit value, it is preferable because the decrease in the crosslink density is unlikely to cause a decrease in mechanical strength.

There is no limitation in particular as a method of making the curable composition of this invention contain arbitrary components, such as the above-mentioned additive, A conventionally well-known mixing, the dispersion | distribution method, etc. are mentioned. In addition, in order to disperse | distribute the said arbitrary component more reliably, it is preferable to perform a dispersion process using a disperser. Specifically, for example, two-roll, three-roll, bead mill, ball mill, sand mill, pebble mill, trom mill, sand grinder, segment barrier triter, planetary stirrer, high speed impeller disperser, high speed stone mill, high speed impact mill , A kneader, a homogenizer, an ultrasonic dispersion machine and the like.

  The viscosity of the curable composition of the present invention can be appropriately adjusted according to the application and usage mode of the curable composition, etc., but from the viewpoint of handleability, coatability, moldability, three-dimensional formability, etc. The viscosity at 25 ° C. in a viscometer (rotor 1 ° 34 ′ × R24) is preferably 10 mPa · s or more, more preferably 30 mPa · s or more, and 50,000 mPa · s or less 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 components, the blending ratio thereof, and the like.

  The coating method of the curable composition of the present invention includes 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, a lip coater method, Although 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, among them, a bar coater method and a gravure coater method are preferable.

  The curable composition of the present invention preferably has a tensile modulus of 2,000 to 6,000 MPa measured using this. Excellent hardness can be obtained when the tensile modulus is 2,000 to 6,000 MPa. A tensile elastic modulus of 2,000 MPa or more is preferable from the viewpoints of abrasion resistance, contamination resistance, abrasion resistance, and the like. On the other hand, it is preferable from the viewpoint of three-dimensional processability that it is 6,000 MPa or less. The tensile elastic modulus is more preferably 2,500 to 5,500 MPa, and still more preferably 3,000 to 5,000 MPa from the viewpoint of making the above-mentioned effect better. In addition, the film forming method and the measuring method at the time of measuring this tensile elasticity modulus are as having shown the Example shown below.

[Cured product / laminate]
A cured product can be obtained by irradiating the above-mentioned curable composition of the present invention with an active energy ray (hereinafter sometimes referred to as "the cured product of the present invention"). As an active energy ray used when hardening a curable composition, an infrared ray, a visible ray, an ultraviolet ray, an X ray, an electron beam, an alpha ray, a beta ray, a gamma ray etc. are mentioned. It is preferable to use an electron beam or ultraviolet light from the viewpoint of apparatus cost and productivity, and as a light source, an electron beam irradiation apparatus, 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 Laser, He-Cd laser, solid-state laser, xenon lamp, high frequency induction mercury lamp, sunlight and the like are preferable.

The irradiation amount of the active energy ray can be appropriately selected according to the type of the active energy ray. For example, when hardening by electron beam irradiation, it is preferable that the irradiation amount is 1-15 Mrad. Moreover, when it harden | cures by ultraviolet irradiation, it is preferable that it is 50-1,500 mJ / cm < ² >.

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

  The thickness of the cured film of the present invention can be appropriately determined depending on the intended application, 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. If the film thickness is more than the above lower limit value, the designability and functionality after three-dimensional processing tends to be good, while if the film thickness is less than the above upper limit, the internal curing property and the three-dimensional processability Tend to be good.

  Moreover, a laminated body can be obtained by forming the above-mentioned hardened | cured material on a base material (Hereafter, it may be called "the laminated body of this invention."). The laminate of the present invention is not particularly limited as long as it has a layer comprising the cured product of the present invention, and a layer other than the substrate and the cured product of the present invention is between the substrate and the cured product of the present invention You may have, It may have on the outer side. Further, the laminate may have a plurality of layers of the base material and the cured product of the present invention.

  As a method of obtaining a laminate having a plurality of cured products, a method in which all the layers are laminated in an uncured state and then cured by active energy rays, or after the lower layer is cured or semi-cured by active energy rays A known method such as a method of applying the upper layer and curing again with active energy rays, a method of applying the respective layers to a release film or a base film, and then bonding the layers together in an uncured or semicured state is applied. Although possible, it is preferable to use a method of curing with active energy rays after laminating in an uncured state from the viewpoint of enhancing the adhesion between layers. As a method of laminating in an uncured state, a known method such as sequential application in which the upper layer is applied after laminating the lower layer or simultaneous multilayer application in which two or more layers are simultaneously applied from the multiple slits is applied Although it is possible, it is not this limitation.

  Examples of the substrate include polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyolefins such as polypropylene and polyethylene, various plastics such as nylon, polycarbonate and (meth) acrylic resin, glass, metals and the like. Among these, polyethylene terephthalate is preferred. The shape of the substrate may be flat such as a film or sheet, or may be formed into various shapes.

  The laminate of the present invention is particularly preferably produced as a cured film by the following method. A preferred method for producing a cured film comprises the steps of applying the curable composition of the present invention onto a substrate, irradiating the curable composition with active energy rays to obtain a cured product, and stretching the cured product. By passing through. The urethane (meth) acrylate oligomer of the present invention exhibits good stretchability in the step of stretching the above-mentioned cured product since it has stretchability after curing which can follow deformation during three-dimensional processing. It also has particularly good suitability to deformation during three-dimensional processing of the resulting cured film.

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

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

  Hereinafter, the present invention will be more specifically described based on examples, but the present invention is not limited at all by the following examples. The values of various manufacturing 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 value of the upper limit or the lower limit described above The range defined by the values of the following examples or the combination of the values of the examples may be used.

[Method of measuring physical properties and characteristics]
The physical property of the urethane (meth) acrylate oligomer and a cured film in the following examples and comparative examples, and the measurement and evaluation method of characteristics are as follows.

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

<Physical properties of cured film>
2-1) Evaluation of handling property (uncured) After coating a curable resin on a polyethylene terephthalate film with a bar coater to form a coated film, the coated film obtained by drying at 120 ° C. for 30 seconds The handling property before curing was evaluated using the degree of sticking (blocking resistance) at the time of film superposition. The coating was allowed to stand at 23 ° C. and 55% relative humidity for 12 hours or more. Next, a polyethylene terephthalate film (untreated type) is overlaid on the surface of the coated film, and a load of 1 kg / cm ² is applied at 23 ° C. and 55% relative humidity for 12 hours, and the coated surface and the untreated surface of the polyethylene terephthalate film Was blocked. After unloading, the ratio of the area in which blocking occurred to the total area applied was visually evaluated according to the following criteria.
○: No blocking part ○-: Blocking area ratio ≦ 10%
Δ: 10% <blocking area ratio ≦ 30%
Δ-: 30% <blocking area ratio ≦ 50%
×: 50% <blocking area ratio

2-2) Evaluation of Coating Film Appearance (After Curing) The coating film appearance of the cured film laminated on the polyethylene terephthalate obtained by the film forming method I described later was visually evaluated according to the following criteria.
:: uniform film thickness, no abnormality such as foreign matter, wrinkles or skin on the coated film surface is observed Δ: foreign matter, wrinkles, or dirt on the coated film surface when the angle of the laminate is changed or fixation is performed by applying light Abnormality such as Yuzu skin is seen x: Abnormality such as foreign matter, wrinkles, or yuzu skin is observed on the coating film surface

2-3) The film forming method cured film laminated on a polyethylene terephthalate obtained by the I evaluating later abrasion resistance, haze value measured before the scratch test was H _1. On the other hand, the weight of 200 gf (per 4 cm ² area) is placed on a dry cloth (cotton--for dyeing fastness test according to JIS L 0803) under an atmosphere of 23 ° C. and 55% RH, and the polyethylene terephthalate obtained by the above film forming method I the cured film surface that is laminated on at Gakushin abrasion tester (manufactured by Toyo Seiki) 50 rubbed back and forth, the haze values measured immediately after the H _2. The difference between H ₂ and H ₁ (ΔH (ΔH = H ₂ -H ₁ )) was determined and evaluated based on the following criteria. In the above, the haze value was measured according to JIS K7105 using a haze meter ("HAZE METER HM-65W" manufactured by Murakami Color Research Laboratory Co., Ltd.).
○: ΔH ≦ 2.5
−-: 2.5 <ΔH ≦ 4.5
Δ: 4.5 <ΔH ≦ 6.5
Δ-: 6.5 <ΔH ≦ 8.5
×: 8.5 <ΔH

2-4) Evaluation of stain resistance (after curing) Using a cured film obtained by the film forming method I or film forming method III described later and a stretched film after curing, a sunscreen cream (Nivea SUN Protect Face manufactured by Nivea Kao Corporation) The essence milk) (hereinafter referred to as "contaminant") was brought into contact and allowed to stand, and then the degree of contamination after wiping off the contaminant with water-containing absorbent cotton was visually evaluated. The evaluation film and its contact conditions and evaluation criteria are as follows.
(1) 0.005 g / cm ² is brought into contact with the cured film obtained by the film forming method I, and allowed to stand at 80 ° C. for 1 hour (2) 0 film after curing obtained by the film forming method III .005 g / cm ² are brought into contact, and allowed to stand at 23 ° C. for 4 hours (3) After curing, the stretched film obtained by the film forming method III is brought into contact with 0.005 g / cm ² The evaluation criteria are as follows.
:: no contamination is present −: (pollution area ratio) ≦ 10%
Δ: 10% <(contaminated part area ratio) ≦ 30%
Δ-: 30% <(contaminated area ratio) ≦ 50%
×: 50% <(% of contaminated area)

2-5) Evaluation of elastic modulus (after curing) The cured film of film forming method II described later is cut into a width of 10 mm, and a temperature of 23 ° C. using a Tensilon tensile tester (“RTC-1210A” manufactured by Orientec Co., Ltd.) The tensile modulus of elasticity was measured by conducting a tensile test under the conditions of a humidity of 55% RH, a tensile speed of 50 mm / min and a distance between chucks of 50 mm. 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 the tensile test under the above conditions is extended, and 100 The stress converted at% elongation was taken as the tensile modulus. When the pressure was 2,000 to 6,000 MPa, it was evaluated that the mechanical strength was good.

2-6) Evaluation of Stretchability (After Curing) The cured film of film forming method II described later was cut into a width of 10 mm, and a temperature of 140 using a Tensilon tensile tester (“MX2-500N” manufactured by IMADA CO., LTD.) C., tensile speed 40 mm / min, distance between chucks 40 mm, elongation at break was measured, and evaluated based on the following criteria.
:: elongation 100% or more ○: elongation 60% or more and less than 100% ×: elongation less than 60%

[Raw materials and solvents]
Raw materials and solvents used in Examples and Comparative Examples below and their abbreviations are as follows. (Compound (A): Polyisocyanate)
IPDI: Isophorone diisocyanate (manufactured by Evonik Degussa Japan Co., Ltd., trade name "VESTANAT IPDI")

(Compound (B): linear aliphatic diol having 2 to 5 carbon atoms)
EG: ethylene glycol

(For comparison with compound (B): linear aliphatic diol having 6 carbon atoms)
1,6-HD: 1,6-hexanediol

(Compound (C): Multifunctional (Meth) Acrylate Having a Hydroxyl Group)
V-300: Osaka Organic Co., Ltd. trade name Biscoat (registered trademark) 300 (a mixture of 40 to 45% by weight of pentaerythritol triacrylate and 35 to 40% by weight of pentaerythritol tetraacrylate (catalog value) (OH value: 120 mg KOH / g) )
In addition, OH number equivalent: OH group equivalent (molecular weight per one hydroxyl group) 468 is calculated from 120 mg KOH / g, and all components consist of pentaerythritol triacrylate (PET3A) and pentaerythritol tetraacrylate (PET4A). It calculated with PET4A = 298 / (468-298) = 64/36 (weight ratio).

(For comparison with compound (C): monofunctional (meth) acrylate having a hydroxyl group)
HEA: 2-hydroxyethyl acrylate

(Organic solvent)
MEK: methyl ethyl ketone (SP value: 9.0)
IPA: isopropyl alcohol (SP value: 11.5)

Example 1
In a four-necked flask fitted with a stirrer, reflux condenser, dropping funnel and thermometer, put 163 g of IPDI, 40 g of ethylene glycol, further add 203 g of methyl ethyl ketone and 0.02 g of bismuth tris (2-ethylhexanoate) The reaction was carried out for 9 hours while heating to 80 ° C. in an oil bath. After completion of the reaction, the reaction solution is cooled to 60 ° C., and then 0.25 g of bismuth tris (2-ethylhexanoate), 0.15 g of methyl hydroquinone and 96 g of methyl ethyl ketone are added, and 96 g of V-300 (PET 3A: 61 g / PET 4 A: 35 g) The reaction was started dropwise. The reaction is carried out while heating to 70 ° C. in an oil bath for 10 hours, and after confirming the end point of the reaction by disappearance of the peak derived from isocyanate (NCO) group in the infrared absorption spectrum, 400 g of methyl ethyl ketone is added and a curable resin is obtained. The composition was obtained. About the urethane acrylate oligomer in the obtained curable composition, the weight average molecular weight and number average molecular weight were measured by the method of said 1-1). The obtained results are shown in Table 1.

(Calculation of urethane bond amount)
The amount of urethane bonds of the above urethane acrylate oligomer was calculated using the following values. -The number of moles of IPDI: 0.73 moles (= 163 g (charged amount of IPDI) / 222 (molecular weight of IPDI))
-Mol number of EG: 0.64 mol (= 40 g (charged amount of EG) / 62 (molecular weight of EG))-Mol number of PET 3 A: 0.20 mol (= 61 g (charged amount of PET 3 A) / 298 (PET 3 A) Molecular weight of)))
-Number of isocyanate groups: 1.47 eq (= 0.73 moles (number of moles of IPDI) x 2 (number of functional groups of isocyanate groups)
Number of hydroxyl groups: 1.49 eq (= 0.64 moles (number of moles of EG) × 2 (number of hydroxyl functional groups) +0.20 (number of moles of PET 3A) × 1 (number of hydroxyl functional groups)

Since PET3A is not included in the constituent component of the urethane (meth) acrylate oligomer in the number of excess hydroxyl groups (0.02 eq (= 1.49 eq-1.47 eq)), PET3A: 0.18 mol for calculation of the amount of urethane bond It was calculated using ((0.20 eq-0.02 eq) / number of hydroxyl functional groups: 1).
(Urethane bond amount)
= 1.47 eq (the smaller of the total equivalent number of isocyanate groups and the total equivalent number of all functional groups that react with isocyanate groups such as hydroxyl and amino groups) / (163 g + 40 g + 0.18 mol × 298)
5.8 5.8 × 10 ^-3 eq / g

(Calculation of (meth) acryloyl group amount)
The amount of (meth) acryloyl groups of the above urethane acrylate oligomer was calculated as follows.
((Meth) acryloyl group amount)
= 0.18 eq (0.20 mol (number of moles of hydroxyalkyl poly (meth) acrylate excluding the amount of components added in excess))-0.02 mol x 3 (number of (meth) acryloyl groups) / (163 ( Amount of components of IPDI) + 40 (amount of components of EG) + 0.18 mol × 298 (amount of components of PET 3A))
2.1 2.1 × 10 ^-3 eq / g

(Film forming method I)
A curable resin is coated on a polyethylene terephthalate film by a bar coater to form a coating, and then dried at 120 ° C. for 30 seconds, and accelerated using an electron beam irradiation apparatus (CB175, manufactured by Eye Graphic Co.) The dried coating is irradiated with an electron beam at a voltage of 165 kV and an irradiation dose of 5 Mrad, and further cured at 23 ° C. for 1 day to form a cured film, and a cured film of about 5 μm thickness is laminated on polyethylene terephthalate. I got a membrane. The physical properties of the above 2-2) to 2-4) were evaluated for the obtained cured film. These results are shown in Table 1.

(Film forming method II)
The curable composition is coated on a polyethylene terephthalate film by a bar coater to form a coating, and then dried at 120 ° C. for 30 seconds, and an accelerating voltage is applied using an electron beam irradiation apparatus (CB175, manufactured by Eye Graphic Co.) The dried coating is irradiated with an electron beam under the conditions of 165 kV and an irradiation dose of 5 Mrad, and further cured at 23 ° C. for 1 day to form a cured film, and then the cured film is peeled from the polyethylene terephthalate film to cure about 30 μm thick I got a membrane. The physical properties of the above-mentioned 2-5) and 2-6) were evaluated for the obtained cured film. These results are shown in Table 1.

(Film forming method III)
The cured film of the above-mentioned film forming method I is cut into a width of 10 mm, and a temperature of 140 ° C., a tensile speed of 40 mm / minute, and a distance between chucks of 40 mm using a Tensilon tensile tester The film was stretched by 20 mm (50% elongation) under the following conditions to obtain a stretched film after curing. The physical property evaluation of said 2-4 was performed about the obtained stretched film after hardening. The results are shown in Table 1.

Example 2
In a four-necked flask equipped with a stirrer, reflux condenser, dropping funnel and thermometer, put 184 g of IPDI, 45 g of ethylene glycol, 230 g of methyl ethyl ketone, and 0.02 g of bismuth tris (2-ethylhexanoate). The reaction was carried out for 9 hours while heating to 80 ° C. in an oil bath. After completion of the reaction, the reaction solution is cooled to 60 ° C., and then 0.25 g of bismuth tris (2-ethylhexanoate), 0.15 g of methyl hydroquinone and 70 g of methyl ethyl ketone are added, 11 g of HEA and 59 g of V-300 (PET 3A: 38 g /) PET4A: 21 g) was added dropwise to initiate the reaction. The reaction is carried out while heating to 70 ° C. in an oil bath for 10 hours, and after confirming the end point of the reaction by disappearance of the peak derived from isocyanate (NCO) group in the infrared absorption spectrum, 400 g of methyl ethyl ketone is added to make the curable composition I got a thing.

  About the urethane acrylate oligomer in the obtained curable composition, it carried out similarly to Example 1, measured the weight average molecular weight and number average molecular weight, and computed the amount of urethane bond and the amount of (meth) acryloyl groups. Further, the curable composition was formed into a film in the same manner as in Example 1 to evaluate the physical properties of the above 2-1) to 2-6). These results are shown in Table 1.

[Example 3]
In a four-necked flask fitted with a stirrer, reflux condenser, dropping funnel and thermometer, put 190 g of IPDI, 50 g of ethylene glycol, further add 240 g of methyl ethyl ketone and 0.02 g of bismuth tris (2-ethylhexanoate) The reaction was carried out for 9 hours while heating to 80 ° C. in an oil bath. After completion of the reaction, the reaction solution is cooled to 60 ° C., and then 0.25 g of bismuth tris (2-ethylhexanoate), 0.15 g of methyl hydroquinone and 60 g of methyl ethyl ketone are added, and 60 g of V-300 (PET 3A: 38 g / PET 4 A: 22 g) The reaction was started dropwise. The reaction is carried out while heating to 70 ° C. in an oil bath for 10 hours, and after confirming the end of the reaction by disappearance of the peak derived from isocyanate (NCO) group in the infrared absorption spectrum, 200 g of methyl ethyl ketone and 200 g of isopropyl alcohol are added , A curable composition was obtained.

  About the urethane acrylate oligomer in the obtained curable composition, it carried out similarly to Example 1, measured the weight average molecular weight and number average molecular weight, and computed the amount of urethane bond and the amount of (meth) acryloyl groups. In addition, the curable composition was formed into a film in the same manner as in Example 1 to evaluate the physical properties of the above 2-1) to 2-6). These results are shown in Table 1.

Comparative Example 1
In a four-necked flask fitted with a stirrer, reflux condenser, dropping funnel and thermometer, put 140 g of IPDI, 31 g of ethylene glycol, further add 170 g of methyl ethyl ketone and 0.02 g of bismuth tris (2-ethylhexanoate) The reaction was carried out for 9 hours while heating to 80 ° C. in an oil bath. After completion of the reaction, the reaction solution is cooled to 60 ° C., and then 0.25 g of bismuth tris (2-ethylhexanoate), 0.15 g of methyl hydroquinone and 130 g of methyl ethyl ketone are added, and 130 g of V-300 (PET 3A: 83 g / PET 4 A: 47 g) The reaction was started dropwise. The reaction is carried out while heating to 70 ° C. in an oil bath for 10 hours, and after confirming the end point of the reaction by disappearance of the peak derived from isocyanate (NCO) group in the infrared absorption spectrum, 400 g of methyl ethyl ketone is added to make the curable composition I got a thing.

  About the urethane acrylate oligomer in the obtained curable composition, it carried out similarly to Example 1, measured the weight average molecular weight and number average molecular weight, and computed the amount of urethane bond and the amount of (meth) acryloyl groups. In addition, the curable composition was formed into a film in the same manner as in Example 1 to evaluate the physical properties of the above 2-1) to 2-6). These results are shown in Table 1.

Comparative Example 2
In a four-necked flask fitted with a stirrer, reflux condenser, dropping funnel and thermometer, put 214 g of IPDI, 51 g of ethylene glycol, further add 265 g of methyl ethyl ketone and 0.03 g of bismuth tris (2-ethylhexanoate) The reaction was carried out for 9 hours while heating to 80 ° C. in an oil bath. After completion of the reaction, the reaction solution was cooled to 60 ° C., 0.06 g of bismuth tris (2-ethylhexanoate), 0.15 g of methyl hydroquinone and 35 g of methyl ethyl ketone were further added, and 35 g of HEA was dropped to start the reaction. The reaction is carried out while heating to 70 ° C. in an oil bath for 10 hours, and after confirming the end point of the reaction by disappearance of the peak derived from isocyanate (NCO) group in the infrared absorption spectrum, 400 g of methyl ethyl ketone is added to make the curable composition I got a thing.

  About the urethane acrylate oligomer in the obtained curable composition, it carried out similarly to Example 1, measured the weight average molecular weight and number average molecular weight, and computed the amount of urethane bond and the amount of (meth) acryloyl groups. Further, the curable composition was formed into a film in the same manner as in Example 1 to evaluate the physical properties of the above 2-1) to 2-6). These results are shown in Table 1.

Comparative Example 3
In a four-necked flask equipped with a stirrer, reflux condenser, dropping funnel, and thermometer, 142 g of IPDI, 65 g of 1,6-hexanediol, further add 207 g of methyl ethyl ketone, bismuth tris (2-ethylhexanoate) 0.02 g was added and reacted for 9 hours while heating to 80 ° C. in an oil bath. After completion of the reaction, the reaction solution is cooled to 60 ° C., and then 0.25 g of bismuth tris (2-ethylhexanoate), 0.15 g of methyl hydroquinone and 93 g of methyl ethyl ketone are added, and 93 g of V-300 (PET 3A: 59 g / PET 4 A: 34 g) The reaction was started dropwise. The reaction is carried out while heating to 70 ° C. in an oil bath for 10 hours, and after confirming the end point of the reaction by disappearance of the peak derived from isocyanate (NCO) group in the infrared absorption spectrum, 400 g of methyl ethyl ketone is added to make the curable composition I got a thing.

  About the urethane acrylate oligomer in the obtained curable composition, it carried out similarly to Example 1, measured the weight average molecular weight and number average molecular weight, and computed the amount of urethane bond and the amount of (meth) acryloyl groups. In addition, the curable composition was formed into a film in the same manner as in Example 1 to evaluate the physical properties of the above 2-1) to 2-6). These results are shown in Table 1.

[Evaluation results]
From the results shown in Table 1, the following can be understood when Examples 1 to 3 and Comparative Examples 1 to 3 are compared. First, Comparative Example 1 is an example in which the value is smaller than the urethane bond amount in the urethane (meth) acrylate oligomer of the present invention, and the value of the (meth) acryloyl group amount is large. In comparison, the handling properties (when uncured) and the stretchability were poor. Moreover, although the comparative example 2 is an example which does not use a compound (C) but uses "HEA" instead, abrasion resistance and contamination resistance after hardening are compared with Examples 1-3. It was bad. Furthermore, Comparative Example 3 is an example using a smaller one than the urethane bond amount in the urethane (meth) acrylate oligomer of the present invention, but compared with Examples 1 to 3, the handling property (when uncured) ), Stain resistance after stretching and curing were poor.

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

Claims (9)

It is obtained by reacting at least the following compound (A), compound (B) and compound (C), and the urethane bond amount is 5.2 × 10 ^{−3 to} 10.0 × 10 ⁻³ eq / g, (meth) acryloylyl A composition comprising a urethane (meth) acrylate oligomer having a basis weight of 0.8 × 10 ^{−3 to} 3.0 × 10 ⁻³ eq / g and an organic solvent, and the content of the urethane (meth) acrylate oligomer being curable The curable composition which is 60 weight% or more with respect to the total of all the components except the organic solvent in it .
Compound (A): Polyisocyanate Compound (B): Linear aliphatic diol compound having 2 to 5 carbon atoms (C): Polyfunctional (meth) acrylate having a hydroxyl group The curable composition according to claim 1, wherein the weight average molecular weight (Mw) of the urethane (meth) acrylate oligomer is 1,500 to 30,000. The curable composition according to claim 1, wherein the compound (B) contains at least ethylene glycol. The urethane (meth) acrylate oligomer is obtained by reacting the compound (A) and the compound (B) to obtain a urethane prepolymer and then reacting the compound (C) with the urethane prepolymer. The curable composition according to any one of Items 1 to 3. The curable composition according to any one of claims 1 to 4 , wherein the solubility parameter of the organic solvent is 8.0 to 11.5. The curable composition according to any one of claims 1 to 5 , wherein the solid concentration is 5 to 90% by weight. A cured product obtained by irradiating the curable composition according to any one of claims 1 to 6 with an active energy ray. A laminate obtained by applying the curable composition according to any one of claims 1 to 6 on a substrate and irradiating it with active energy rays to cure it. A step of applying the curable composition according to any one of claims 1 to 6 on a substrate, a step of irradiating the curable composition with an active energy ray to obtain a cured product, and stretching the cured product A method of producing a cured film, comprising the steps of: