Hardening compound, hardening composition, and method for producing hardening composition

Abstract

Provided are: a curable composition containing a urethanation reaction product of a branched-chain polyolefin diol that includes a carbon-carbon double bond in a side chain thereof, at least one selected from an isocyanurate, an adduct, and a biuret of an aliphatic diisocyanate having a total of 6-10 carbon atoms, and a hydroxy saturated C1-C4 alkyl (meth)acrylate; a method for producing the same; a specific curable compound contained in the curable composition; etc.

Description

Cross - reference to related applications

[0001] This application claims the priority of Japanese Patent Application No. 2020 - 124356 and Japanese Patent Application No. 2020 - 203305, and these applications are incorporated by reference into the description of this application specification.

Technical Field

[0002] The present invention relates to a curable compound, a curable composition containing the curable compound, and a method for producing the curable composition.

Background Art

[0003] Conventionally, curable compositions that cure by light irradiation, moisture (humidity), etc. are known. As this type of curable composition, for example, a curable composition that cures by light irradiation, which contains a urethane acrylate (curable compound) synthesized from hydrogenated polybutadiene diol or hydrogenated polyisoprene diol and having a number - average molecular weight of 1,000 to 20,000, a monofunctional (meth) acrylate monomer, and an initiator having an absorption band at a wavelength of 380 nm or more, is known (for example, Patent Document 1). In the curable composition described in Patent Document 1, the content of the above initiator is 10 to 15 parts by mass with respect to a total of 100 parts by mass of the above curable compound and the above monomer.

[0004] The curable composition described in Patent Document 1 is used in the application of coating electronic circuits. For example, it is applied onto an electronic circuit and then irradiated with light, and cures by the reaction of the above curable compound and the above monomer. The curable composition described in Patent Document 1 can also cure with light from an LED light source and can have good moisture resistance and electrical insulation properties, etc.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, due to reasons such as the curable compound contained in the curable composition described in Patent Document 1 having no unsaturated bonds due to hydrogenation, the cured product obtained by curing the curable composition described in Patent Document 1 may not necessarily have its tackiness (micro-adhesiveness) on the surface suppressed. In this case, problems may occur such that foreign substances (for example, those that can reduce the electrical insulation of the cured product) adhere to the surface of the cured product, or marks where an object such as a packaging material comes into contact with the cured product remain on the surface of the cured product. Further, even if the surface tackiness of the cured product is suppressed, there is a problem that the cured product does not have appropriate stretchability. Therefore, there is a demand for a curable composition in which the surface tackiness of the cured product after curing is suppressed and the cured product has appropriate stretchability.

[0007] In view of the above problems, requirements, etc., an object of the present invention is to provide a curable compound and a curable composition capable of obtaining a cured product with suppressed surface tackiness and having appropriate stretchability.

[0008] Another object of the present invention is to provide a method for producing a curable composition for producing a curable composition containing the above-described curable compound.

Means for Solving the Problems

[0009] In order to solve the above problems, the curable compound according to the present invention is characterized by being represented by the following general formula (I).

Chemical formula

[0010] The curable composition according to the present invention contains a urethanization reaction product of a branched polyolefin diol having a carbon-carbon double bond in the side chain, at least one selected from isocyanurate, adduct, and biuret forms of an aliphatic diisocyanate having 6 to 10 carbon atoms in total, and a hydroxy-saturated C1-C4 alkyl (meth)acrylate.

[0011] The method for producing the curable composition according to the present invention is characterized by producing a curable composition containing a reaction product of the urethanization reaction by urethanization reaction in the presence of a branched polyolefin diol having a carbon-carbon double bond in the side chain, at least one selected from isocyanurate, adduct, and biuret forms of an aliphatic diisocyanate having 6 to 10 carbon atoms in total, and a hydroxy-saturated C1-C4 alkyl (meth)acrylate.

Brief Description of the Drawings

[0012]

Figure 1

Embodiments for Carrying Out the Invention

[0013] [Curable Compound] Hereinafter, an embodiment of the curable compound according to the present invention will be described.

[0014] The curable compound of this embodiment is represented by the following general formula (I).

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0015] The curable compound of this embodiment contains at least one of an acryloyl group of (meth)acrylate or an isocyanate group (-NCO) in the molecule. Specifically, as shown by Z in general formulas (II) and (III), the curable compound of this embodiment has at least one of a (meth)acryloyl group or an isocyanate group (-NCO) involved in the curing reaction in the molecule. Therefore, it can be cured by irradiation with light such as ultraviolet light and also by moisture (such as humidity) in the air. For example, by irradiation with light such as ultraviolet light, a polymerization reaction occurs between the above compounds by the (meth)acryloyl group. When the compounds polymerize with each other, polymerization (curing reaction) can proceed. Also, for example, a reaction occurs between the -NCOs of the above compounds through water (H2O) contained in the moisture in the air, and the compounds are bonded to each other. Polymerization (curing reaction) can also proceed by this bonding. Therefore, the curable compound of this embodiment can be sufficiently cured by light or moisture. The surface tackiness of the cured cured product is suppressed, and moreover, the cured product can have appropriate extensibility. When the curable compound of this embodiment contains both a (meth)acryloyl group and an isocyanate group (-NCO) in the molecule, the curable compound of this embodiment can be sufficiently cured by either light or moisture.

[0016] In general formula (I), X is a branched polyolefin structure containing a carbon-carbon double bond in the side chain. Such a polyolefin structure preferably has a main chain composed of saturated hydrocarbons (alkylene groups) and a side chain composed of a polyolefin structure containing a carbon-carbon double bond. Such a polyolefin structure preferably contains a carbon-carbon double bond at the tip of the side chain. Examples of such a branched polyolefin include polybutadiene (1,2-polybutadiene, 1,2-polybutadiene containing a 1,4 addition polymerization butadiene structure), polyisoprene (1,2-polyisoprene, 3,4-polyisoprene), and the like. Note that a part of the side chain in X may be composed of saturated hydrocarbons. In other words, a part of the plurality of side chains may be composed of saturated hydrocarbons (alkyl groups). Preferably, 5% or more (for example, particularly 10% or more) of the total number (number of moles) of the side chains in X contains a carbon-carbon double bond.

[0017] In the polyolefin structure in general formula (I), the molecular weight is preferably 1000 or more and 6000 or less. By having such a molecular weight of 1000 or more, a decrease in the mechanical properties of the cured product can be more effectively suppressed. Also, by having such a molecular weight of 6000 or less, phase separation of the cured product and non-uniformity can be more effectively suppressed. Note that the molecular weight in the polyolefin structure can be determined by the standard polystyrene conversion value measured by GPC (gel permeation chromatography) before synthesizing the curable compound of general formula (I).

[0018] In general formula (I), the two Ys each independently represent either general formula (II) or general formula (III). In general formula (I), the two Ys may have the same molecular structure as each other or different molecular structures from each other.

[0019] In General Formula (II) and General Formula (III), each T independently represents a partial structure of an isocyanurate body, an adduct body, or a biuret body of an aliphatic diisocyanate having 6 to 10 carbon atoms in total. In other words, each T corresponds to a structure obtained by removing -NCO from the isocyanurate body, adduct body, or biuret body as described above. For example, the structure represented by General Formula (a) is the above-described isocyanurate body structure, the structure represented by General Formula (b) is the above-described adduct body structure, and the structures represented by General Formula (c) or (d) are biuret body structures. In the curable compound represented by General Formula (I), the plurality of Ts may be the same as each other or may be different from each other. Note that in General Formulas (a) to (d), the notation "Z or NHCOO-" described in parentheses is not included in T in General Formula (II) or (III).

[0020] The aliphatic diisocyanate having 6 to 10 carbon atoms in total before forming the above-described isocyanurate body structure, adduct body structure, or biuret body structure has isocyanate groups at both ends of a linear alkylene group having 4 to 8 carbon atoms. Since T contained in Y is composed of, for example, an isocyanurate body structure, an adduct body structure, or a biuret body structure of an aliphatic diisocyanate, it does not include either a benzene ring structure or a saturated cycloalkyl structure (a saturated structure in which the ring is composed only of carbon atoms). Since T is composed of an isocyanurate body structure, an adduct body structure, or a biuret body structure of an aliphatic diisocyanate, Y does not have a benzene ring structure. Since Y does not have a benzene ring structure, the weather resistance of the cured product after curing is improved.

[0021] Examples of the aliphatic diisocyanate having 6 to 10 carbon atoms in total include hexamethylene diisocyanate (HMDI).

[0022] The above-described isocyanurate body is a trimer of the above-described aliphatic diisocyanate. For example, the structure obtained by removing the terminal -NCO of such a trimer corresponds to the structure represented by General Formula (a).

[0023] The above adduct is a reaction product of the above aliphatic diisocyanate and a triol having 3 to 6 carbon atoms. For example, the structure obtained by removing the terminal -NCO from such a reaction product corresponds to the structure represented by the general formula (b). The triol having 3 to 6 carbon atoms contains only carbon (C), oxygen (O), and hydrogen (H) as elements. Examples of the triol having 3 to 6 carbon atoms include trimethylolpropane (CH3-CH2-C(CH2-OH)3), glycerin, and the like.

[0024] The above biuret is a reaction product of the above aliphatic diisocyanate and water or a tertiary alcohol. For example, the structure of the inner part rather than the terminal -NCO of such a reaction product corresponds to the structure represented by the general formula (c) or the general formula (d), respectively.

[0025] When Y is represented by the general formula (III), the two Ls in the general formula (III) are each independently a residue of a diol (glycol) which may contain an ether bond. Each L is preferably a glycol residue having 2 to 6 carbon atoms. L may be, for example, a residue of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol (such as 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, etc.), pentylene glycol (such as 1,2-pentanediol, 1,5-pentanediol, etc.), neopentyl glycol, or the like. Since L is a residue after the -OH groups of the diol compound have undergone a urethanization reaction with -NCO, for example, if L is a residue of dipropylene glycol, L is represented by -C3H6-O-C3H6-. L is preferably a residue of dipropylene glycol or neopentyl glycol in that the above curable compound has good solubility and the cured product can have good heat resistance. In general formula (III), the two Ls are each independent and may be the same as or different from each other. In other words, the plurality of Ls contained in the curable compound represented by general formula (I) may be the same as or different from each other.

[0026] In general formulas (II) and (III), the plurality of Zs each independently represent the molecular structure represented by the above general formula (α) or -NCO. Among the plurality of Zs in the curable compound represented by general formula (I), at least one may be the molecular structure represented by the above general formula (α) and at least one may be -NCO. In other words, the curable compound represented by general formula (I) may have at least one each of the molecular structure represented by general formula (α) and -NCO in the molecule. On the other hand, all of the plurality of Zs in the curable compound represented by general formula (I) may be the molecular structure represented by the above general formula (α), or all of the plurality of Zs may be -NCO.

[0027] The plurality of Zs represented by general formulas (II) and (III) are each independent in the curable compound represented by general formula (I) and may be the same as or different from each other. Since the two Ys represented by general formula (I) each contain a plurality of Zs (two Zs or four Zs), general formula (I) contains four or more and eight or less Zs. In general formula (I) including general formulas (II) and (III), the plurality of Zs are each defined independently.

[0028] In general formulas (a) to (d), R a1 ~R a3 、R b1 ~R b3 、R c 、R d1 ~R d3 、R e1 ~R e3 are organic groups containing at least carbon atoms. R a1 ~R a3 、R b1 ~R b3 、R c 、Rd1 ~R d3 、R e1 ~R e3 may contain a urea bond, a biuret bond, or an allophanate bond. R a1 ~R a3 、R b1 ~R b3 、R d1 ~R d3 、R e1 ~R e3 is preferably a saturated hydrocarbon having 4 to 8 carbon atoms, more preferably a straight-chain saturated hydrocarbon having 6 carbon atoms, but may contain a heteroatom (N, O, S, P, etc.) and may have a branched-chain structure. R c is preferably a saturated hydrocarbon having 4 to 8 carbon atoms, more preferably a branched-chain saturated hydrocarbon having 6 carbon atoms, but may contain a heteroatom (N, O, S, P, etc.) and may have a straight-chain structure.

[0029] In the general formula (α), the saturated hydrocarbon group of Q having 2 to 4 carbon atoms is preferably linear. In other words, Q is preferably a linear saturated hydrocarbon group having 2 to 4 carbon atoms. The number of carbon atoms of the saturated hydrocarbon group in Q is preferably 2.

[0030] As the molecular structure represented by the general formula (α), the one represented by the following formula (α-1) is preferable. By having the molecular structure represented by the following formula (α-1), it has an ethylene group with less steric hindrance, and has the advantage that the polymerization rate by irradiation with ultraviolet rays or the like is improved. When the number of carbon atoms of Q in the general formula (α) is 1 (that is, a methylene group), it tends to decompose slightly during curing. [Chemical formula]

[0031] Examples of the curable compound (compound for curing) represented by the general formula (I) include compounds represented by the following general formulas (I-A) to (I-G).

[0032] [Chemical formula] [However, R a1 , R a2 , R a3 is, independently of one another, a straight-chain saturated hydrocarbon having 4 to 8 carbon atoms, p is 15 or more and 300 or less, and M is H or CH3.]

[0033]

Chemical formula

[0034]

Chemical formula

[0035]

Chemical formula

[0036]

Chemical formula

[0037] [Chemical formula] [However, R b1 , R b2 , R b3 is independently a linear saturated hydrocarbon having 4 to 8 carbon atoms, p is 15 to 300, and M is H or CH3.]

[0038] When Y is represented by the general formula (III), the curable compound of this embodiment is represented by, for example, the following general formula (I-G).

[0039] [Chemical formula] [However, R a1 , R a2 , R a3 is independently a linear saturated hydrocarbon having 4 to 8 carbon atoms, X is as described above, and a plurality of Z (eight Zs) are as described above.]

[0040] [Curable composition] Next, an embodiment of the curable composition according to the present invention will be described. Since the curable composition of this embodiment contains the above curable compound, for the same reasons as described above, the surface tackiness of the cured product is suppressed, and moreover, the cured product can have appropriate extensibility.

[0041] The curable composition of this embodiment contains a branched polyolefin diol having a carbon-carbon double bond in the side chain (hereinafter also simply referred to as <Component A>), at least one selected from isocyanurate, adduct, and biuret forms of an aliphatic diisocyanate having a total carbon number of 6 to 10 (hereinafter also simply referred to as <Component B>), and a hydroxy-saturated C1-C4 alkyl (meth)acrylate (hereinafter also simply referred to as <Component C>), and is a urethanization reaction product.

[0042] Since the curable composition of the present embodiment contains the urethanization reaction product described above, it contains at least the curable compound represented by the above general formula (I). Further, the curable composition of the present embodiment contains, in addition to the curable compound represented by the above general formula (I), other products generated by the urethanization reaction. Further, the curable composition of the present embodiment also contains a trace amount of urethanization reaction catalyst compounded for the urethanization reaction. The urethanization reaction product will be described in detail later.

[0043] The curable composition of the present embodiment contains at least the curable compound represented by the above general formula (I) and can be cured at least by light irradiation. Also, it may be curable by moisture. Further, the curable composition of the present embodiment also contains other products generated by the above urethanization reaction, and such other products can also cause a curing reaction by light irradiation or moisture.

[0044] <Component A> Component A is a branched polyolefin diol containing a carbon-carbon double bond in the side chain. The polyolefin diol has hydroxy groups at both ends of the molecule. The olefin moiety does not contain polar groups such as ether groups and ester groups and is composed only of hydrocarbons. Component A is composed of a main chain and side chains. The main chain may contain saturated hydrocarbons or unsaturated hydrocarbons. The side chain of the olefin moiety contains a carbon-carbon double bond.

[0045] Examples of Component A include polybutadiene diol (1,2-polybutadiene diol, 1,2-polybutadiene diol containing a 1,4 addition polymerization butadiene structure), polyisoprene diol (1,2-polyisoprene diol, 3,4-polyisoprene diol). As Component A, polybutadiene diol (1,2-polybutadiene diol) is preferable in that it can impart sufficient mechanical flexibility to the cured product (film) after curing.

[0046] The molecular weight of Component A is preferably 1000 or more and 6000 or less.

[0047] <Component B> Component B is a polyisocyanate and is at least one selected from isocyanurate bodies, adduct bodies, and biuret bodies of aliphatic diisocyanates having 6 or more and 10 or less carbon atoms in total. Component B has 3 or 4 isocyanate groups in the molecule. Component B preferably has neither a benzene ring structure (aromatic ring structure) nor a saturated cycloalkyl structure (saturated structure in which the ring is composed only of carbon atoms) in the molecule.

[0048] The isocyanurate body as Component B is, for example, a trimer of hexamethylene diisocyanate (HMDI) described above and has 3 isocyanate groups in the molecule.

[0049] The adduct body as Component B is, for example, a reaction product of trimethylolpropane and an aliphatic diisocyanate having 6 or more and 10 or less carbon atoms in total (such as HMDI described above). Such an adduct body has 3 isocyanate groups in the molecule.

[0050] As Component B, in terms of the fact that the weather resistance after curing is good because it does not contain a benzene ring, and in terms of the good solubility in the diluent when a diluent coexists in the urethanization reaction, an adduct body obtained by reacting hexamethylene diisocyanate (HMDI) and trimethylolpropane, or an isocyanurate body (trimer) of hexamethylene diisocyanate (HMDI) is preferable.

[0051] <Component C> Component C is a C1-C4 saturated alkyl ester of (meth)acrylic acid, has one hydroxy group bonded to any carbon of the saturated hydrocarbon moiety having 1 to 4 carbon atoms, and has one (meth)acryloyl group. The notation "C1-C4 saturated alkyl" represents the number of carbon atoms (1 or more and 4 or less) of the hydrocarbon moiety ester-bonded to (meth)acrylic acid. Component C is preferably a hydroxy-saturated C2-C3 alkyl (meth)acrylate (the number of carbon atoms of the saturated hydrocarbon moiety is 2 or more and 3 or less). In this specification, the notation "(meth)acryl" means including both "acryl" and "methacryl".

[0052] Examples of Component C include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc. In terms of better polymerizability by light irradiation, Component C is preferably 2-hydroxyethyl (meth)acrylate, and more preferably 2-hydroxyethyl acrylate.

[0053] The molar ratio (B / A) of Component B to Component A in the urethanization reaction is preferably 2.0 or more, and more preferably 4.0 or more. Also, such a molar ratio (B / A) is preferably 8.0 or less. When such a molar ratio (B / A) is 2.0 or more, there is an advantage that the curability of the above curable compound and curable composition becomes better. When such a molar ratio (B / A) is 8.0 or less, there is an advantage that the storage stability of the above curable compound and curable composition becomes better.

[0054] In the urethanization reaction, the molar ratio of component C to component B (C / B) is preferably 0.2 or more, more preferably 0.4 or more. Further, such molar ratio (C / B) is preferably 1.2 or less, more preferably 1.0 or less. When such molar ratio (C / B) is 0.2 or more, there is an advantage that the photocurability of the above-mentioned curable compound and curable composition can be further enhanced. When such molar ratio (C / B) is 1.2 or less, there is an advantage that the moisture curability of the above-mentioned curable compound and curable composition can be further enhanced.

[0055] In the urethanization reaction, the molar ratio of component C to component A (C / A) is preferably 2.0 or more. Further, such molar ratio (C / A) is preferably 8.0 or less, more preferably 4.0 or less. When such molar ratio (C / A) is 2.0 or more, there is an advantage that the photocurability of the above-mentioned curable compound and curable composition can be further enhanced. When such molar ratio (C / A) is 8.0 or less, there is an advantage that the storage stability of the above-mentioned curable compound and curable composition becomes better.

[0056] As described above, by changing the blending molar ratio of each component to be subjected to the urethanization reaction, the curing reactivity of the curable compound represented by the general formula (I) described above can be adjusted. Specifically, by relatively increasing the blending amount of component C, the curing reactivity (polymerization reactivity) of the curable compound by light irradiation or the like can be enhanced. For example, by blending component A and component C in an amount such that all the isocyanate groups of component B undergo a urethanization reaction, and further blending component C in excess, a curable compound that cures (polymerizes) only by light irradiation or the like can be obtained. Further, by relatively increasing the blending amount of component B, the curing reactivity (reactivity between isocyanate groups) of the curable compound by moisture or the like can be enhanced. For example, by blending component B in an amount such that the isocyanate groups are in excess relative to the total amount of the hydroxy groups contained in component A and component C, a curable compound that cures even by moisture or the like can be obtained.

[0057] The curable composition of the present embodiment is not particularly limited as long as it contains the urethanization reaction product of the above-mentioned component A, component B, and component C. For example, the curable composition of the present embodiment may contain the urethanization reaction product of the above-mentioned component A, component B, and component C, and further the following component D. In other words, the above-mentioned urethanization reaction product may be obtained by reacting the above-mentioned component A, component B, and component C with the following component D. Further, the curable composition of the present embodiment may contain a urethanization reaction product obtained by reacting, in addition to the above-mentioned component A, component B, and component C, also a component A' similar to component A. Specifically, as such a component A', a branched polyolefin diol having a side chain composed only of saturated hydrocarbons may be employed, and a urethanization reaction product obtained by further reacting such a component A' may be contained.

[0058] <Component D> Component D is a diol (glycol) having 10 or less carbon atoms and may contain an ether bond. Component D is preferably a glycol having 2 or more and 6 or less carbon atoms. Component D is preferably at least one selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol (such as 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, etc.), pentylene glycol (such as 1,2-pentanediol, 1,5-pentanediol, etc.), and neopentyl glycol. In terms of the point that the generated urethanization reaction product becomes more easily soluble in an alkyl (meth)acrylate monomer (described later), and the point that the cured product can have better moisture resistance and heat resistance, component D is preferably at least one of dipropylene glycol and neopentyl glycol.

[0059] In the urethanization reaction, the molar ratio (D / B) of component D to component B is preferably 0.3 or more, more preferably 0.5 or more. Also, such molar ratio (D / B) is preferably 0.8 or less, more preferably 0.7 or less. When such molar ratio (D / B) is 0.3 or more, there is an advantage that the elongation property of the cured product becomes better. When such molar ratio (D / B) is 0.8 or less, there are advantages that the moisture resistance of the cured product and the storage stability of the above-mentioned curable compound and curable composition become better.

[0060] Examples of the urethanization reaction product obtained by reacting component D as well include a curable compound represented by general formula (I-G) and a reaction product schematically represented as shown in FIG. 1. FIG. 1 schematically shows an example of a reaction product (curable compound) when Y in general formula (I) is represented by general formula (III).

[0061] Examples of the above-mentioned urethanization reaction product include compounds represented by the above-mentioned general formula (I) such as the above-mentioned general formula (I-A) to (I-G).

[0062] From another perspective, examples of the above-mentioned urethanization reaction product include a compound having only an isocyanate group as a reactive group, a compound having only a (meth)acryloyl group as a reactive group, and the like. From still another perspective, examples of the above-mentioned urethanization reaction product include a urethanization reaction product of component A and component B in which component C is not introduced into the molecule, a urethanization reaction product of component B and component C in which component A is not introduced into the molecule, and the like.

[0063] The curable composition of the present embodiment may further contain a compound that does not undergo a urethanization reaction. Such a compound may be a photopolymerizable monomer (described in detail later) that produces a polymerization reaction product by light irradiation. Examples of such a photopolymerizable monomer include a saturated cycloalkyl (meth)acrylate monomer having a saturated cyclic hydrocarbon structure and a (meth)acryloyl group in the molecule, or a saturated linear alkyl (meth)acrylate monomer having a saturated linear hydrocarbon structure and a (meth)acryloyl group in the molecule. Such a compound may be blended as a diluent before the urethanization reaction in order to reduce the viscosity in the urethanization reaction system, or may be blended (described in detail later) after the urethanization reaction in order to impart desired physical properties to the cured product after curing.

[0064] Note that the curable composition of the present embodiment may contain unreacted Component A, Component B, and Component C that did not undergo a urethanization reaction. Further, the curable composition of the present embodiment may contain a urethanization reaction catalyst blended for the promotion of the urethanization reaction. As described above, the curable composition of the present embodiment contains various reaction products and unreacted substances. Therefore, it can be said that it is approximately impractical to specify the molecular structure of all the contained compounds. In other words, it can be said that it is approximately impractical to directly specify the structure or properties of all the compounds contained in the curable composition of the present embodiment. However, since the molecular structure of the compound before the urethanization reaction is specified and the product by the urethanization reaction can be sufficiently predicted, it is sufficiently possible to predict the molecular structure of the reaction product.

[0065] The curable composition of the present embodiment may further contain a photopolymerizable monomer, an isocyanate monomer, a photopolymerization initiator, etc., added after the urethanization reaction. The curable composition of the present embodiment preferably does not contain a compound having a benzene ring (an aromatic hydrocarbon composed of six cyclic carbon atoms) in the molecule as a urethanization reaction product (curable compound), a photopolymerizable monomer, or an isocyanate monomer.

[0066] Examples of the photopolymerizable monomer include monofunctional photopolymerizable monomers. Examples of the monofunctional photopolymerizable monomers include alkyl (meth) acrylate monomers having a hydrocarbon group (alkyl group) with 18 or fewer carbon atoms. Specifically, examples of the monofunctional photopolymerizable monomers include saturated cycloalkyl (meth) acrylate monomers having a saturated cyclic hydrocarbon structure and one (meth) acryloyl group in the molecule, or saturated chain alkyl (meth) acrylate monomers having a saturated chain hydrocarbon structure and one (meth) acryloyl group in the molecule.

[0067] Specifically, the curable composition of the present embodiment may contain at least one of the above-mentioned saturated cycloalkyl (meth) acrylate monomer or the above-mentioned saturated chain alkyl (meth) acrylate monomer as a photopolymerizable monomer that does not undergo a urethanization reaction. These (meth) acrylate monomers are compounds that produce a polymerization reaction product by light irradiation.

[0068] The saturated cycloalkyl (meth) acrylate monomer is preferably a saturated alicyclic monomer having 8 to 15 carbon atoms in the molecule. The saturated cycloalkyl (meth) acrylate monomer preferably does not contain any of a benzene ring and polar groups such as an ether bond (-CH2-O-CH2-), -OH group, and -COOH group in the molecule. In the saturated cycloalkyl (meth) acrylate monomer, the saturated cycloalkyl structure may be a saturated hydrocarbon structure composed of 4 to 8 carbon atoms without containing a hetero atom. The saturated cycloalkyl (meth) acrylate monomer may be monocyclic, bicyclic, or polycyclic. The bicyclic or polycyclic saturated cycloalkyl structure may share 2 or more carbon atoms. In the case of a bicyclic or polycyclic saturated cycloalkyl (meth) acrylate monomer, at least one ring structure may be a saturated alkyl structure, for example, all ring structures may be saturated alkyl structures. In the saturated cycloalkyl (meth) acrylate monomer, a methyl group or an ethyl group may be further bonded to the carbon of the saturated cyclic hydrocarbon structure.

[0069] Specifically, examples of the saturated cycloalkyl (meth)acrylate monomer include isobornyl (meth)acrylate (containing a norbornane structure), dicyclopentadiene oxyethyl (meth)acrylate (containing a norbornane structure), dicyclopentanyl (meth)acrylate (containing a norbornane structure), dicyclopentenyl oxyethyl (meth)acrylate (containing a norbornane structure), adamantyl (meth)acrylate, etc. Among them, a saturated cycloalkyl (meth)acrylate monomer containing a norbornane structure is preferred. By including the saturated cycloalkyl (meth)acrylate monomer in the above curable composition, the moisture resistance of the cured product after curing can be improved.

[0070] The saturated linear alkyl (meth)acrylate monomer is preferably a (meth)acrylate monomer having a saturated linear hydrocarbon with 8 to 15 carbon atoms in the molecule. The saturated linear alkyl (meth)acrylate monomer preferably does not contain any of a benzene ring and polar groups such as an ether bond (-CH2-O-CH2-), -OH group, and -COOH group in the molecule. In the saturated linear alkyl (meth)acrylate monomer, the saturated linear hydrocarbon structure may not contain atoms other than C and H and may be a saturated linear hydrocarbon structure composed of 7 to 11 carbon atoms. By including the saturated linear alkyl (meth)acrylate monomer in the above curable composition, the flexibility of the cured product obtained by curing the curable composition can be further improved.

[0071] In the saturated linear alkyl (meth)acrylate monomer, the saturated linear hydrocarbon structure may be linear or branched. In other words, the saturated linear hydrocarbon structure may be a saturated linear hydrocarbon structure or a saturated branched hydrocarbon structure. Further in other words, the saturated linear alkyl (meth)acrylate monomer may be a saturated linear alkyl (meth)acrylate monomer or a saturated branched alkyl (meth)acrylate monomer. As the saturated chain alkyl (meth)acrylate monomer, a saturated branched chain alkyl (meth)acrylate monomer is preferred in that it can more sufficiently dissolve the above urethanized reaction product in the curable composition. Thereby, a cured film closer to being uniform can be obtained with less influence from the substrate supporting the cured product, the thickness of the cured product, or the curing reaction conditions.

[0072] The hydrocarbon structure of the saturated straight chain alkyl (meth)acrylate monomer may be a saturated straight chain alkyl structure. Specifically, examples of the saturated straight chain alkyl (meth)acrylate monomer include n-heptyl (meth)acrylate, n-octyl (meth)acrylate, n-nonyl (meth)acrylate, n-decyl (meth)acrylate, tridecyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, and the like.

[0073] The hydrocarbon structure of the saturated branched chain alkyl (meth)acrylate monomer may be a saturated branched chain alkyl structure, and may be an iso structure, a sec structure, a neo structure, or a tert structure. Specifically, examples of the saturated branched chain alkyl (meth)acrylate monomer include isooctyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and the like. As the above saturated branched chain alkyl (meth)acrylate monomer, at least one of isononyl (meth)acrylate and isodecyl (meth)acrylate is preferred in terms of better solubility with the above urethanized reaction product and easier obtainment of a cured film closer to being uniform.

[0074] The above-mentioned monofunctional photopolymerizable monomers can be used singly or in combination of two or more. The curable composition of this embodiment preferably contains both the above-mentioned saturated cycloalkyl (meth)acrylate monomer and the above-mentioned saturated linear alkyl (meth)acrylate monomer as photopolymerizable monomers, and more preferably contains a saturated cycloalkyl (meth)acrylate monomer containing a norbornane structure and a saturated branched-chain alkyl (meth)acrylate monomer.

[0075] In the curable composition of this embodiment, the mass ratio (η / θ) of the saturated cycloalkyl (meth)acrylate monomer (η) to the saturated linear alkyl (meth)acrylate monomer (θ) is preferably 1 or more and 8 or less, more preferably 5 or less, and even more preferably 3 or less. When the saturated linear alkyl (meth)acrylate monomer is particularly a saturated branched-chain alkyl (meth)acrylate monomer, it is preferable that the mass ratio (η / θ) is within the above range. When the above mass ratio (η / θ) is 1 or more, the elongation property of the cured product becomes better, and when the above mass ratio (η / θ) is 8 or less, there is an advantage that the electrical performance (electrical insulation property) of the cured product becomes better. Therefore, when the above mass ratio (η / θ) is within the above range, there is an advantage that a cured product having better balance between electrical insulation performance and elongation performance can be obtained.

[0076] As the photopolymerizable monomer, a monomer that does not contain any of a benzene ring and polar groups such as an ether bond (-CH2-O-CH2-), -OH group, and -COOH group is preferable in terms of better weather resistance of the cured product after curing. In addition, the curable composition of the present embodiment may contain a polyfunctional photopolymerizable monomer. Examples of the polyfunctional (meth)acrylate monomer include neopentyl glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, dicyclopentanyl di(meth)acrylate, 1,6 - hexanediol di(meth)acrylate, polypropylene glycol di(meth)acrylate, ethylene oxide - modified bisphenol A di(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethylene oxide - modified trimethylolpropane tri(meth)acrylate, ethylene oxide - modified pentaerythritol tetra(meth)acrylate, tris[(meth)acryloxyethyl] isocyanurate, ethylene oxide - modified dipentaerythritol hexa(meth)acrylate, epoxy (meth)acrylate, and the like.

[0077] Examples of the isocyanate monomer include aromatic diisocyanate monomers, alicyclic diisocyanate monomers, aliphatic diisocyanate monomers, etc. These monomers may have 2 to 4 isocyanate groups in the molecule. Examples of the aromatic diisocyanate monomer include monomers such as tolylene diisocyanate, diphenylmethane diisocyanate, diphenylpropane diisocyanate, triphenylmethane diisocyanate, phenylene diisocyanate, xylylene diisocyanate, naphthalene diisocyanate, and tolidine diisocyanate. Examples of the alicyclic diisocyanate monomer include monomers such as hydrogenated tolylene diisocyanate, hydrogenated diphenylmethane diisocyanate, hydrogenated xylylene diisocyanate, cyclohexylene diisocyanate, 3 - isocyanatomethyl - 3,5,5 - trimethylcyclohexyl isocyanate (isophorone diisocyanate), 3 - isocyanatoethyl - 3,5,5 - trimethylcyclohexyl isocyanate, 3 - isocyanatoethyl - 3,5,5 - triethylcyclohexyl isocyanate, and the like. Examples of the aliphatic diisocyanate monomer include a hexamethylene diisocyanate monomer and the like. The isocyanate monomer may be an adduct, biuret, isocyanurate, or polymeric form of at least any one of the above monomers. These monomers can be used alone or in combination of two or more. As the isocyanate monomer, a monomer containing no benzene ring and no unsaturated bond is preferable in terms of better weather resistance of the cured product after curing.

[0078] The photopolymerization initiator is not particularly limited as long as it is a compound that generates radicals by irradiated light (such as ultraviolet rays). Examples of the photopolymerization initiator include acetophenone-based photoinitiators, benzoin-based photoinitiators, benzophenone-based photoinitiators, thioxanthone-based photoinitiators, acylphosphine oxide-based photoinitiators, and the like. Commercially available products can be used as the photopolymerization initiator.

[0079] The curable composition of the present embodiment may contain a photosensitizer, a polymerization inhibitor, an antioxidant, a dye (fluorescent dye), a pigment, etc., as necessary.

[0080] The curable composition of the present embodiment preferably contains 10% by mass or more of the compound represented by the general formula (I). Thereby, the cured product after curing can be more suppressed in surface tackiness and have appropriate stretchability. The curable compound of the present embodiment may contain 90% by mass or less of the compound represented by the general formula (I). The curable composition of the present embodiment may contain 10% by mass or more and 85% by mass or less of the above-mentioned photopolymerizable monomer that does not undergo urethanization reaction, such as an alkyl (meth)acrylate monomer. The curable composition of the present embodiment may contain 2% by mass or more and 20% by mass or less of an isocyanate monomer other than the above-mentioned curable compound.

[0081] [Method for Producing Curable Composition] Subsequently, an embodiment of the method for producing a curable composition according to the present invention will be described. According to the method for producing a curable composition of this embodiment, a curable composition containing the above-described curable compound can be obtained.

[0082] In the method for producing a curable composition of this embodiment, a branched polyolefin diol having a carbon-carbon double bond in the side chain (the above A component), at least one selected from isocyanurate bodies, adduct bodies, and biuret bodies of aliphatic diisocyanates having 6 to 10 carbon atoms in total (the above B component), and hydroxy-saturated C1-C4 alkyl (meth)acrylate (the above C component), a curable composition containing a reaction product of the urethanization reaction is produced by a urethanization reaction in the presence thereof.

[0083] Specifically, the method for producing a curable composition of this embodiment includes a reaction step of synthesizing a urethanization reaction product containing the above-described curable compound by a urethanization reaction in the presence of at least the above A component, B component, C component, and a urethanization reaction catalyst. The method for producing a curable composition of this embodiment further includes an addition step of adding a photopolymerizable monomer, an isocyanate monomer, and a photopolymerization initiator after the reaction step.

[0084] Regarding the A component, B component, C component, urethanization reaction catalyst, and D component that can be further used in the above production method, they are as described above.

[0085] In the above production method, after mixing the above components and replacing the air in the reaction vessel with nitrogen to prevent reaction with moisture, the reaction step is usually carried out.

[0086] In the reaction step, general reaction conditions suitable for the urethanization reaction can be adopted. Preferably, in the reaction step, the urethanization reaction is carried out by maintaining a temperature of 50 to 70°C for 0.5 to 3 hours.

[0087] In the reaction process, the ratio (molar ratio) of the blending amounts of the preferable components A, B, and C, and the component D to be reacted as necessary is as described above.

[0088] In the reaction process, a compound that does not participate in the urethanization reaction and generates a polymerization reaction product by light irradiation may be further coexisted. Examples of such a compound include the above-described photopolymerizable monomer.

[0089] In the addition process, after the urethanization reaction, the above-described photopolymerizable monomer, isocyanate monomer, and photopolymerization initiator may be further added. Since the photopolymerizable monomer and isocyanate monomer to be further added have a low viscosity, they serve as a solvent for diluting the above-described curable compound, while they themselves are cured by light or moisture, so they also serve to more sufficiently cure the cured product. The more the photopolymerizable monomer and isocyanate monomer are further blended, the lower the viscosity of the curable composition for curing becomes, and the process of applying the curable composition can be simplified.

[0090] In the addition process, a photosensitizer, a polymerization inhibitor, an antioxidant, dyes such as fluorescent dyes, pigments, etc. may be further blended as necessary.

[0091] The curable composition containing the curable compound of the present embodiment can be cured by irradiation with light such as ultraviolet rays, for example, and used as a cured product. Also, for example, it can be cured by moisture (humidity) in the air and used as a cured product. Specifically, after applying the above-described curable composition to an electronic circuit to be coated, the composition may be cured by irradiating it with light such as ultraviolet rays to form a cured coating film. Furthermore, by leaving it in the air for several hours to several days, the curing reaction due to moisture in the air can also be advanced. Note that the curable composition containing the curable compound of the present embodiment is preferably cured by both the curing reaction by light and the curing reaction by moisture, but it may be cured by either one of the curing reactions.

[0092] As the light irradiated to promote the curing reaction, ultraviolet rays can be used. As the light source, a high-pressure mercury lamp, a metal halide lamp, a xenon lamp, a chemical lamp, an LED lamp, etc. can be used. As the irradiation intensity, for example, 10~10,000 mW / cm 2 can be adopted.

[0093] The temperature of the air for promoting the curing reaction by moisture is preferably 20~40°C, and the humidity of the air is preferably 40~90 RH%.

[0094] Examples of the object to be coated with the above curable composition include electronic circuits or terminals on mounting substrates used in precision equipment, electronic circuits or terminals on mounting substrates mounted on automobiles, bicycles, railways, airplanes, ships, etc., electronic circuits or terminals on mounting substrates used in mobile devices (mobile phones, digital cameras, digital video cameras, etc.), electronic circuits or terminals on substrates used in outdoor equipment (water heaters, outdoor air conditioners, etc.), or electronic circuits or terminals on mounting substrates used in water-related equipment such as washing machines, warm water washing toilet seats, and dishwashers.

[0095] The curable compound, curable composition, and method for producing the composition of the present embodiment are as exemplified above, but the present invention is not limited to the curable compound, curable composition, and method for producing the composition exemplified above. That is, various forms used in general curable compounds, curable compositions, and methods for producing the compositions can be adopted as long as the effects of the present invention are not impaired.

[0096] The matters disclosed by this specification include the following. (1-1) The curable compound represented by the above general formula (I). (1-2) In general formula (I), two Ys each independently represent either general formula (II) or general formula (III), and in general formulas (II) and (III), each T represents general formula (a), the curable compound described in the above (1-1). (1-3) In general formula (I), two Ys represent general formula (III), and in general formula (III), each T represents general formula (a), the curable compound described in the above (1-1). (1-4) General formula (I) is at least one selected from the group consisting of the above general formulas (I-A), (I-B), (I-C), (I-D), (I-E), (I-F), and (I-G), the curable compound described in the above (1-1). (2-1) A branched polyolefin diol containing a carbon-carbon double bond in the side chain, At least one selected from isocyanurate, adduct, and biuret forms of an aliphatic diisocyanate having 6 to 10 carbon atoms in total, A hydroxy-saturated C1-C4 alkyl (meth)acrylate, A curable composition containing a urethanization reaction product thereof. (2-2) The curable composition according to the above (2-1), wherein the urethanization reaction product is further a urethanization reaction product with a diol compound. (2-3) The urethanization reaction product, A saturated cycloalkyl (meth)acrylate monomer having a saturated cyclic hydrocarbon structure and a (meth)acryloyl group in the molecule, A saturated linear alkyl (meth)acrylate monomer having a saturated linear hydrocarbon structure and a (meth)acryloyl group in the molecule, A curable composition according to the above (2-1) or (2-2), containing the same. (2-4) The curable composition according to the above (2-3), wherein the mass ratio of the saturated cycloalkyl (meth)acrylate monomer to the saturated linear alkyl (meth)acrylate monomer is 1 or more and 8 or less. (2-5) The curable composition according to any one of (2-2) to (2-4) above, wherein the diol compound is a glycol (diol) having 2 to 6 carbon atoms. (2-6) The saturated cycloalkyl (meth) acrylate monomer contains a norbornane structure in the molecule. The curable composition according to any one of (2-3) to (2-5) above, wherein the saturated linear alkyl (meth) acrylate monomer contains a saturated branched-chain alkyl structure in the molecule. (2-7) The polybutadiene diol as the polyolefin diol, The isocyanurate form of the aliphatic diisocyanate having 6 to 10 carbon atoms in total, The hydroxyethyl (meth) acrylate as the hydroxy-saturated C1-C4 alkyl (meth) acrylate, The curable composition according to any one of (2-1) to (2-6) above, containing the urethanization reaction product of. (3-1) A branched polyolefin diol having a carbon-carbon double bond in the side chain, At least one selected from the isocyanurate form, adduct form, and biuret form of an aliphatic diisocyanate having 6 to 10 carbon atoms in total, A hydroxy-saturated C1-C4 alkyl (meth) acrylate, A method for producing a curable composition, which produces a curable composition containing the reaction product of the urethanization reaction by the urethanization reaction in the presence of. (3-2) The method for producing a curable composition according to (3-1) above, wherein the urethanization reaction is further carried out in the presence of a diol compound. (3-3) The polybutadiene diol as the polyolefin diol, The isocyanurate form of the aliphatic diisocyanate having 6 to 10 carbon atoms in total, Hydroxyethyl (meth)acrylate as the hydroxy-saturated C1-C4 alkyl (meth)acrylate, and A method for producing a curable composition containing a reaction product of the urethanization reaction by the urethanization reaction in the presence of , the method for producing a curable composition according to (3-1) or (3-2) above. (3-4) During or after the urethanization reaction, A saturated cycloalkyl (meth)acrylate monomer having a saturated cyclic hydrocarbon structure and a (meth)acryloyl group in the molecule, and A method for producing a curable composition according to any one of (3-1) to (3-3) above, further comprising at least one of a saturated linear alkyl (meth)acrylate monomer having a saturated linear hydrocarbon structure and a (meth)acryloyl group in the molecule. [Examples]

[0097] Next, the present invention will be described in more detail by experimental examples, but the present invention is not limited thereto.

[0098] As follows, (A) to (C) were mixed, and (D) and (E) were further mixed as necessary to carry out a urethanization reaction to produce a curable composition containing a curable compound represented by the general formula (I).

[0099] [Raw materials in the reaction process] [Component (A)] (A-1) A branched polyolefin diol having a carbon-carbon double bond in the side chain · 1,2-Polybutadiene diol (average molecular weight 3,000) Product name: "NISSO-PB G-3000", manufactured by Nippon Soda Co., Ltd. : Hydroxyl value (KOHmg / g = 29.5) (A-2) A branched polyolefin diol having a carbon-carbon double bond in the main chain and the side chain respectively · 1,2-Polybutadiene diol containing a 1,4-addition polymerization butadiene structure (average molecular weight 2,800) 1,4-addition polymerization / 1,2-addition polymerization = 8 / 2 (molar ratio) Product name: "Poly bd R45TH", manufactured by Idemitsu Kosan Co., Ltd. : Hydroxyl value (KOHmg / g = 46.6) (A’) Similar component of the above (A-1) (side chain is a saturated hydrocarbon group) · Hydrogenated polybutadiene diol (average molecular weight 3,100) Product name: "NISSO-PB GI-3000", manufactured by Nippon Soda Co., Ltd. : Hydroxyl value (KOHmg / g = 29.3) (Component B) Derivative of aliphatic diisocyanate with 6 to 10 carbon atoms in total · Isocyanurate derivative of hexamethylene diisocyanate (HMDI) (trifunctional) Product name: "DURANATE TPA-100: Isocyanate group content 23%", manufactured by Asahi Kasei Corporation (Used only in Example 8) Product name: "Coronate HXLV: Isocyanate group content 23.2%", manufactured by Tosoh Corporation (Component C) Hydroxy-saturated C1-C4 alkyl (meth)acrylate · 2-Hydroxyethyl acrylate (commercially available product) (Component D) Diol compound · Dipropylene glycol (commercially available product) (Others) · Photopolymerizable monomer a (reaction solvent / diluent) (isobornyl acrylate, commercially available product) · Photopolymerizable monomer b (reaction solvent / diluent) (isononyl acrylate, commercially available product) · Urethanization reaction catalyst (dibutyltin dilaurate, commercially available product)

[0100] <Raw materials in the addition process> · Photopolymerizable monomer a (isobornyl acrylate, commercially available product) · Photopolymerizable monomer b (isononyl acrylate, commercially available product) · Photopolymerizable monomer c (lauryl acrylate, commercially available product) · Photopolymerizable monomer d (isodecyl acrylate, commercially available product) · Photopolymerizable monomer e (trimethylolpropane triacrylate, commercially available product), trifunctional with crosslinking property · Polyfunctional isocyanate a Isocyanurate derivative of hexamethylene diisocyanate (HMDI) Product name: "DURANATE TPA-100", manufactured by Asahi Kasei Corporation · Polyfunctional isocyanate b Isocyanurate derivative of hexamethylene diisocyanate (HMDI) Product name: "CORONATE HXLV", manufactured by Tosoh Corporation · Photoinitiator, product name: "IRGACURE 907", manufactured by IGM Resins · Photosensitizer (2,4-diethylthioxanthone) Product name: "KAYACURE DETX-S", manufactured by Nippon Kayaku Co., Ltd. · Fluorescent dye, product name: "Tinopal OB", manufactured by BASF Japan Ltd.

[0101] (Example 1) Using the compounding amounts shown in Table 1, in the presence of the above (A) to (D), etc., and a reaction solvent and a catalyst, a urethanization reaction was carried out at 60°C for 1 hour to perform the reaction process. Next, using the compounding amounts shown in Table 1, the above raw materials were added to and mixed with the composition after the reaction process to perform the addition process. In this way, a curable composition containing a curable compound represented by the general formula (I) was produced.

[0102] (Examples 2 to 9, Comparative Examples 1 and 2) A curable composition was produced in the same manner as in Example 1, except that the compounding amounts shown in Table 1 and Table 2 were changed. In each reaction process of Examples 3 to 9, the relative molar ratio of component (B) was set to 6.0. However, it was confirmed that gelation occurred during the reaction. Therefore, in order to suppress such gelation, in the actual reaction process, the above relative molar ratio was set to 8.0, etc.

[0103] When the product of the reaction steps of Examples 1 to 3 above was analyzed by FT-IR, it was confirmed that the compound represented by General Formula (I) containing General Formula (a) was synthesized.

[0104] The compounding compositions for producing the curable compositions (curable compounds) of the respective examples are shown in Tables 1 and 2. In each table, the numerical values in parentheses indicate the relative molar ratios of the molecules of the respective components. Such molar ratios were calculated based on the hydroxyl value of component (A) (or component (A')). In all the examples, component B in an amount such that the isocyanate groups were in excess with respect to the total amount of the hydroxyl groups contained in components A and C was blended. Thereby, a curable composition that cures not only by light irradiation but also by moisture was produced.

[0105] [Table 1]

[0106] [Table 2]

[0107] The respective curable compositions produced in the examples and comparative examples were evaluated as follows. Specifically, the surface tackiness, elongation rate, and volume resistivity of the cured products (cured films) obtained by curing the produced curable compositions were examined. Generally, the higher the volume resistivity, the more sufficient the curing has progressed.

[0108] <Curing treatment> Each composition was coated on a tin plate of 0.3×130×180 mm (for surface tackiness evaluation / volume resistance measurement) or a 50-μm-thick PET film subjected to a release treatment (for elongation rate measurement) so that the thickness of the cured product after curing would be 100 μm. Then, ultraviolet rays were irradiated with a 500-W UV lamp so that the integrated light amount would be 3000 mJ / cm 2 of light intensity. Further, it was left standing in a thermo-hygrostat set at 40°C / 90% RH for 72 hours to apply a curing treatment by moisture.

[0109] <Surface tackiness of the cured product (cured film)> After obtaining a cured film on a tin plate by the above method, a 50-μm-thick PET film (not subjected to release treatment) cut into a size of 10 mm square was overlaid on the cured film. Subsequently, at room temperature, it was arranged so that the PET film was on the lower side and the tin plate was on the upper side, and it was confirmed whether the PET film would fall within 30 seconds. When the PET film fell, it was judged that there was no surface tackiness, and when it did not fall, it was judged that there was surface tackiness.

[0110] <Elongation rate of the cured product (cured film)> After obtaining a cured film on a 50-μm-thick PET film by the above method, punching was performed in the shape of dumbbell No. 2 specified in JIS K6251 using a Thomson blade. Then, the cured film was peeled off from the PET film, and a tensile test was performed at room temperature by the method specified in the above JIS regulations. The tensile speed was set at 300 mm / min, and the elongation rate was calculated as a percentage by the formula elongation rate = (increase in the length of the cured film at break) / (original length of the cured film).

[0111] <Volume resistivity> On each cured product cured as described above, a paste-like silver conductive paint was applied in a circular shape (diameter 30 mm). It was dried at 60°C for 30 minutes to form the upper electrode. On the other hand, the tin plate arranged on the opposite side of each cured product was used as the lower electrode. At room temperature, a voltage of DC100V was applied, and the resistance value after 60 seconds was determined. Then, the resistance value was multiplied by the electrode area and divided by the thickness of the cured product (cured film) to obtain the volume resistivity.

[0112] The evaluation results of each cured product after curing are shown in Table 1 and Table 2. As can be understood from the evaluation results shown in Table 1 and Table 2, the cured products obtained by curing the curable compositions of each example were suppressed in surface tackiness and had appropriate stretchability compared to the cured products of the compositions of the comparative examples. Incidentally, an appropriate elongation rate is, for example, about 30 to 150%. If the elongation rate is too large, since it flows at high temperatures, problems such as a decrease in solder resistance may occur. On the other hand, if the elongation rate is too small, in thermal cycling conditions (repeated conditions of high temperature and low temperature), the cured product may not be able to absorb the shrinkage difference with the substrate, and problems such as cracks occurring in the cured product may occur.

[0113] Incidentally, Comparative Example 2 is an example in which a crosslinkable trifunctional acrylate monomer was blended into the composition to obtain a cured product. The cured product obtained by promoting the crosslinking reaction in this way has surface tackiness and an elongation rate that is excessively small. Conventionally, in order to reduce the surface tackiness of a cured product, a method of blending a polyfunctional acrylate monomer into the pre-cured composition to increase the crosslink density during curing has been adopted. According to such a method, when trimethylolpropane triacrylate as in Comparative Example 2 was used as the polyfunctional acrylate monomer, not only did the elongation rate of the cured product become too low (the cured product became too hard), but the surface tackiness could not be reduced either. On the other hand, in the cured products obtained by curing the compositions of the respective examples, it was possible to achieve both suppression of surface tackiness and appropriate elongation. The compositions of the respective examples contain the curable compound of the above general formula (I), and the curable compound contains the above component (A). Component (A) is considered to be able to make the physical properties of the cured product flexible in terms of molecular structure. Therefore, even if it is sufficiently cured to reduce the surface tackiness of the cured product, it is considered that the cured product has appropriate elongation due to the flexible physical properties of component (A).

Industrial Applicability

[0114] The curable compound and curable composition of the present invention are, for example, applied to an electronic circuit and then cured by light irradiation or moisture (humidity) in the air to become a cured product, and are preferably used for coating the electronic circuit with the cured product. The curable composition of the present invention is preferably used, for example, as a curable composition for an insulating film.

Claims

1. A curable compound represented by the following general formula (I). 【Chemical 1】 [In the general formula (I), X represents a branched polyolefin structure having a carbon-carbon double bond in the side chain, two Ys each independently represent either of the following general formula (II) or the following general formula (III), and in the general formulas (II) and (III), each T independently represents any of the following general formulas (a) to (d), at least one of the plurality of Zs is a molecular structure represented by the following general formula (α) and at least one is —NCO, and in the general formula (III), two Ls each independently represent a diol residue.] [Chemical 2] 【Chemical Formula 3】 【Chemical 4】 [In general formula (a), R ａ１ , R ａ２ , R ａ３ each independently represents an organic group. ] 【Chemical Formula 5】 [In general formula (b), R ｂ１ , R ｂ２ , R ｂ３ , R ｃ each independently represents an organic group. ] 【Chemical Formula 6】 [In general formula (c), R ｄ１ , R ｄ２ , R ｄ３ each independently represents an organic group. ] 【Chemical Formula 7】 [In general formula (d), R ｅ１ , R ｅ２ , R ｅ３ each independently represents an organic group. ] 【Chemical 8】 In general formula (α), Q represents a saturated hydrocarbon group having 2 to 4 carbon atoms, and M represents H or CH ３ .]

2. A branched polyolefin diol having a carbon-carbon double bond in the side chain, at least one selected from isocyanurate, adduct, and biuret forms of an aliphatic diisocyanate having 6 to 10 carbon atoms in total, Hydroxy-saturated C １ ~C ４ alkyl (meth)acrylate, and and a urethanization reaction product thereof, wherein the urethanization reaction product has an isocyanate group, a curable composition.

3. The curable composition according to claim 2, wherein the urethanization reaction product is further a urethanization reaction product with a diol compound.

4. The urethanization reaction product, a saturated cycloalkyl (meth)acrylate monomer having a saturated cyclic hydrocarbon structure and a (meth)acryloyl group in the molecule, a saturated linear alkyl (meth)acrylate monomer having a saturated linear hydrocarbon structure and a (meth)acryloyl group in the molecule, The curable composition according to claim 2 or 3, comprising.

5. The curable composition according to claim 4, wherein the mass ratio of the saturated cycloalkyl (meth)acrylate monomer to the saturated linear alkyl (meth)acrylate monomer is 1 or more and 8 or less.

6. A branched polyolefin diol having a carbon-carbon double bond in the side chain, at least one selected from isocyanurate, adduct, and biuret forms of an aliphatic diisocyanate having 6 to 10 carbon atoms in total, Hydroxy-saturated C １ ~C ４ alkyl (meth)acrylate, and A method for producing a curable composition, which comprises a reaction product of the urethanization reaction having an isocyanate group in the molecule by a urethanization reaction in the presence of.

7. The method for producing a curable composition according to claim 6, wherein the urethanization reaction is carried out in the presence of a diol compound.

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