Compound, polymer, curing agent, curable composition, and cured product

Abstract

This compound is represented by formula (1). (In formula (1): R2 and R3 are each a monovalent organic group; R4 is an m-valent organic group; m is an integer of 1 or more; when m = 1, at least two of X, Y, and Z are carbonyloxy bonds, with the remainder being an oxygen atom, -NR- (R is a substituent), or a sulfur atom; and when m = 2 or more, at least one of X, Y, and Z is a carbonyloxy bond, with the remainder being an oxygen atom, -NR- (R is a substituent), or a sulfur atom。)

Description

Compound, polymer, curing agent, curable composition and cured product

[0001] The present invention relates to a compound, a polymer, a curing agent, a curable composition, and a cured product.

[0002] Epoxy compounds are highly reactive and are used as intermediates in various reactions and as raw materials for introducing functional groups. Epoxy compounds are also used as materials that give cured products by reacting with curing agents.

[0003] For example, a known method for curing an epoxy compound involves reacting the epoxy compound with a compound having active hydrogen, such as an amine-based curing agent. In the reaction with the compound having active hydrogen, an active hydrogen group, such as an amino group, is added to the epoxy group of the epoxy compound, thereby opening the epoxy group and generating a hydroxyl group. As a result, the resulting cured product contains hydroxyl groups, which can increase moisture absorption and dielectric constant.

[0004] In response to this, a method of reacting an epoxy compound with an active ester compound has been investigated. In this reaction, no hydroxyl group is generated after the epoxy group of the epoxy compound is ring-opened, so that the moisture absorption and dielectric constant of the resulting cured product can be suppressed. Known active ester compounds include benzyl acetate, p-substituted phenyl acetate esters, methyl benzoate, and benzyl thioacetate (see Non-Patent Document 1).

[0005] Journal of the Chemical Society of Japan 1991 No. 11 Addition reactions of cyclic ethers with various esters

[0006] However, conventional active ester compounds do not yet have sufficient reactivity with epoxy compounds, and therefore, in order to react with epoxy compounds, the reaction temperature must be increased.

[0007] The present invention has been made in view of the above circumstances, and provides a compound, a polymer, a curing agent, a curable composition, and a cured product that can react with an epoxy compound at a low reaction temperature and can suppress the generation of hydroxyl groups, and that can cure the epoxy compound.

[0008] [1] A compound represented by the following formula (1): (In formula (1), R ２ and R ３ are each a monovalent organic group, R ４ is an m-valent organic group, m is an integer of 1 or more, when m = 1, two of X, Y, and Z are carbonyloxy bonds, and the remaining is an oxygen atom, -NR- (R is a substituent), or a sulfur atom, when m = 2 or more, at least one of X, Y, and Z is a carbonyloxy bond, and the remaining is an oxygen atom, -NR- (R is a substituent), or a sulfur atom. [2] The compound according to [1], wherein m is an integer of 2 or more, Z is a carbonyloxy bond, and X and Y are each an oxygen atom, -NR-, or a sulfur atom. [3] The compound according to [1], wherein m is an integer of 2 or more, X and Y are each a carbonyloxy bond, and Z is an oxygen atom, -NR-, or a sulfur atom. [4] A polymer having a structure represented by the following formula (2) or (3): (In formulas (2) and (3), R ２、 R ３ and R ６ are each a monovalent organic group, R ５ is a divalent organic group, R is a group constituting a repeating unit of the polymer, X and Y are each an oxygen atom, —NR— (R is a substituent) or a sulfur atom, and n is an integer of 2 or more.) [5] A polymer having a structure represented by the following formula (4) or (5): (In formulas (4) and (5), R ２、 R ３ and R ７ are each a monovalent organic group, R ８is a divalent organic group, R is a group constituting a repeating unit of a polymer, X is an oxygen atom, —NR— (R is a substituent) or a sulfur atom, and n is an integer of 2 or more.) [6] A curing agent for an epoxy compound, comprising the compound according to any one of [1] to [3] and / or the polymer according to [4] or [5]. [7] A curable composition comprising an epoxy compound and the curing agent according to [6]. [8] The curable composition according to [7], wherein the epoxy compound is an alicyclic epoxy compound. [9] A cured product of the curable composition according to [7] or [8].

[0009] According to the present invention, it is possible to provide a compound, a polymer, a curing agent, a curable composition, and a cured product that can react with an epoxy compound at a low reaction temperature and suppress the generation of hydroxyl groups.

[0010] Fig. 1 is a graph showing the DSC measurement results of Example 1, Example 2, and Reference Example 1. Fig. 2A is a graph showing the DSC measurement results of Compound F, and Fig. 2B is a graph showing the DSC measurement results of Compound H. Fig. 3 is a graph showing the DSC measurement results of TAB. Fig. 4 is a photograph of the heated product of Example 1. Fig. 5 is a graph showing the DSC measurement results for Compound H, where the type of epoxy compound was changed. Fig. 6 is a photograph of each curable composition after drying, taken from directly above the bottom of the vial.

[0011] The present inventors have found that an activated ester compound having a structure in which an acyloxy group is directly bonded to a carbon atom of a triazine ring, unlike conventional activated ester compounds, exhibits high reactivity with epoxy compounds, specifically, can undergo an addition reaction with the epoxy group of an epoxy compound even at a low reaction temperature.

[0012] In particular, it has been found that a polyfunctional active ester compound having two or more acyloxy groups directly bonded to carbon atoms of a triazine ring reacts with an epoxy compound at a lower reaction temperature. Such a polyfunctional active ester compound can cure an epoxy compound at a low reaction temperature, and is therefore suitable as, for example, a curing agent for an epoxy compound.

[0013] The compounds of the present invention will be specifically described below. In this specification, unless otherwise specified, the expression "to" means a numerical range including the lower and upper limits, which are the endpoints.

[0014] 1. Compound The compound of the present invention is an activated ester compound having, in one molecule, two or more structures in which an acyloxy group is bonded to a carbon atom constituting a 1,3,5-triazine ring. This activated ester compound can react with an epoxy compound at a low reaction temperature. The compound may be a low molecular weight compound or a high molecular weight compound.

[0015] The acyloxy group (R-CO-O-) refers to a functional group in which an acyl group (R-CO-) and an oxy group (-O-) are bonded (R in the R-CO-O- and R-CO- both represent substituents). A structure in which an acyloxy group is directly bonded to a carbon atom constituting a 1,3,5-triazine ring is represented, for example, by R-CO-O-* (* represents the bond site to the carbon atom constituting the triazine ring).

[0016] 1-1. Small Molecular Weight Compound One embodiment of the present invention relates to a compound represented by the following formula (1):

[0017] In formula (1), R ２ and R ３ are each a monovalent organic group. The monovalent organic group is a monovalent aliphatic group or a monovalent aromatic group, and the monovalent aliphatic group or monovalent aromatic group may contain elements other than C and H, such as N, O, F, Cl, Br, S, P, or Si.

[0018] A monovalent aliphatic group which may contain other elements refers to a residue obtained by removing one hydrogen atom from a carbon atom of an aliphatic compound, and the aliphatic compound also includes compounds in which multiple aliphatic chains are bonded via a linking group such as an ether bond, and saturated heterocycles. That is, the monovalent aliphatic group may be linear, branched, or cyclic, and includes not only residues consisting of C and H, but also residues containing elements other than C and H. Examples of monovalent aliphatic groups include linear alkyl groups having 1 to 18 carbon atoms such as methyl, ethyl, and propyl groups, branched alkyl groups having 3 to 10 carbon atoms such as isopropyl, sec-butyl, and isobutyl groups, cycloalkyl groups having 3 to 10 carbon atoms such as cyclohexyl groups, and heterocyclic groups such as tetrahydrofuran. These monovalent aliphatic groups may further have a substituent such as an aryl group or a halogen atom.

[0019] A monovalent aromatic group that may contain other elements refers to a residue obtained by removing one hydrogen atom from a carbon atom of an aromatic ring of an aromatic compound, and aromatic compounds also include compounds in which multiple aromatic rings are bonded or condensed, such as biphenyl and naphthalene. That is, monovalent aromatic groups include not only residues consisting of C and H, but also residues containing elements other than C and H. The number of carbon atoms in the monovalent aromatic group may be, for example, 5 to 20. Examples of the aromatic group include aryl groups such as a phenyl group and a naphthalene group, and heteroaryl groups such as a pyridinyl group. These monovalent aromatic groups may further have a substituent such as an alkyl group, an alkoxy group, or a halogen atom.

[0020] Among these, R ２ and R ３ As each of these, a monovalent aliphatic group or a monovalent aromatic group is preferable, an alkyl group or an aryl group is preferable, an alkyl group having 3 or less carbon atoms such as a methyl group, an ethyl group, or a propyl group or a phenyl group is more preferable, and a methyl group is particularly preferable.

[0021] When m is an integer of 2 or more, a plurality of R ２ may be the same or different. ３ may be the same as or different from each other.

[0022] R in formula (1)４ is an m-valent organic group. The m-valent organic group is an m-valent aliphatic group or an m-valent aromatic group, and the m-valent aliphatic group or the m-valent aromatic group may contain an element other than C and H, such as N, O, F, Cl, Br, S, P, or Si.

[0023] An m-valent aliphatic group which may contain other elements refers to a residue obtained by removing m hydrogen atoms from different carbon atoms of an aliphatic compound, and the aliphatic compound also includes compounds in which multiple aliphatic chains are bonded via a linking group such as an ether bond, and saturated heterocyclic rings. The m-valent aliphatic group may be linear, branched, or cyclic, and includes not only residues consisting of C and H, but also residues containing elements other than C and H. Examples of the m-valent aliphatic group include linear alkyl residues having 1 to 18 carbon atoms such as methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, and octylene; branched alkyl residues having 3 to 10 carbon atoms such as isopropylene, sec-butylene, and isobutylene; cycloalkyl residues having 6 to 8 carbon atoms such as cyclohexylene; and heterocyclic residues such as piperazinyl. These m-valent aliphatic groups may further have the substituents described above.

[0024] The m-valent aromatic group, which may contain other elements, refers to a residue obtained by removing m hydrogen atoms from different carbon atoms in the aromatic ring of an aromatic compound, and the aromatic compound also includes compounds in which multiple aromatic rings are bonded or condensed, such as biphenyl and naphthalene. The m-valent aromatic group includes not only residues consisting of C and H, but also residues containing elements other than C and H. Examples of the m-valent aromatic group include residues of benzene, biphenyl, diphenyl ether, diphenyl sulfone, diphenyl ketone, naphthalene, etc., and residues of heterocyclic compounds such as pyridine pyrimidine. These m-valent aromatic groups may further have the above-mentioned substituents.

[0025] In formula (1), m is an integer of 1 or more. In particular, from the viewpoint of further enhancing the curability of the epoxy compound, m is preferably an integer of 2 or more, and more preferably an integer of 3 or more. The upper limit of m is, for example, 6.

[0026] When m = 1, two of X, Y, and Z are carbonyloxy bonds, and the remaining is an oxygen atom, -NR-, or sulfur atom, preferably an oxygen atom or sulfur atom, and more preferably an oxygen atom. When m = 2 or more, at least one of X, Y, and Z is a carbonyloxy bond, and the remaining is an oxygen atom, -NR-, or sulfur atom, preferably an oxygen atom or sulfur atom, and more preferably an oxygen atom. The remaining X, Y, and Z other than the carbonyloxy bond may all be oxygen atoms, all sulfur atoms, all -NR-, or a combination of two selected from oxygen atoms, sulfur atoms, and -NR-. The carbonyloxy bond is represented by *-O-C(=O)- (* is the site bonding to the carbon atom constituting the triazine ring).

[0027] R in —NR— is a hydrogen atom or a substituent, and is preferably a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an aryl group having 6 to 10 carbon atoms. When R is an alkyl group, R and R ２ , R ３ or R ４ may be bonded to each other to form a ring (for example, a nitrogen-containing aliphatic six-membered ring). ４ When m is an m-valent aliphatic group (for example, an alkyl group), and Z is -NR-, the Rs of two -NR- may be bonded to each other to form a ring (for example, a nitrogen-containing aliphatic six-membered ring). For example, when m is 2, R ４ is an alkylene group, and Z is —NR—, then —Z—R ４ -Z- may form a piperazinyl ring as shown in the following formula:

[0028] When m is 2 or more, for example, X may be a carbonyloxy bond, and Y and Z may each be an oxygen atom, —NR—, or a sulfur atom. Alternatively, X and Y may each be an oxygen atom, —NR—, or a sulfur atom, and Z may be a carbonyloxy bond (see formula (1A)). Alternatively, X and Y may each be a carbonyloxy bond, and Z may be an oxygen atom, —NR—, or a sulfur atom (see formula (1B)).

[0029] That is, the active ester compound may be a compound having, in the molecule, a plurality of structures in which one acyloxy group is bonded to a triazine ring (low molecular weight compound A), or may be a compound having, in the molecule, a plurality of structures in which two acyloxy groups are bonded to a triazine ring (low molecular weight compound B).

[0030] 1-1-1. Low Molecular Weight Compound A The compound represented by formula (1) may be a compound represented by formula (1A).

[0031] R in formula (1A) ２ ~R ４ , X and Y are R in formula (1) ２ ~R ４ , X, and Y. When m is an integer of 2 or more, a plurality of R ２ may be the same or different. ３ may be the same as or different from each other.

[0032] Among them, R ４ is preferably selected depending on the physical properties required for the cured product. For example, from the viewpoint of easily obtaining a cured product with high flexibility, the aliphatic groups described above are preferred. On the other hand, from the viewpoint of easily obtaining a cured product with high heat resistance and rigidity, the aromatic groups described above are preferred. ４ Various combinations of X and Y are possible. For example, from the viewpoint of lowering the activation energy of the reaction, it is considered effective to make either X or Y -NR-. Also, from the viewpoint of further increasing the reactivity, it is considered effective to make either X or Y -NR-. ４ An aromatic group is preferred as R. ２ or R ３Although it depends on the combination with, etc., the aromatic group is more preferably an aromatic group which may have an electron-withdrawing group, particularly preferably a group derived from an aromatic ring selected from the group consisting of benzene, naphthalene, diphenyl ether, hexafluoro-2,2-diphenylpropane, benzenesulfonic acid, chlorobenzene, bromobenzene, and iodobenzene, and most preferably a group derived from an aromatic ring selected from the group consisting of diphenyl ether and hexafluoro-2,2-diphenylpropane.

[0033] In formula (1A), m is an integer of 2 or greater. From the viewpoint of further enhancing the curability of the epoxy compound, m is preferably 2 or greater, and more preferably 3 or greater. The upper limit of m is not particularly limited, but can be, for example, 6 or less.

[0034] Preferred examples of the compound represented by formula (1A) include those in which m is an integer of 2 to 4 and R ４ is an aromatic group, and R ２ and R ３ are each an alkyl group or an aryl group, and X and Y are each an oxygen atom or a sulfur atom; m is an integer of 2 to 3, and R ４ is an aromatic group, and R ２ and R ３ are each an alkyl group having 3 or less carbon atoms, such as a methyl group, an ethyl group, or a propyl group, or a phenyl group, and X and Y are oxygen atoms; m is an integer of 2 to 3, and R ４ is a group derived from a benzene ring, and R ２ and R ３ is an alkyl group having 3 or less carbon atoms, such as a methyl group, an ethyl group, or a propyl group, and X and Y are oxygen atoms; ４ is a group derived from a benzene ring, and R ３ and R ４ Particularly preferred are compounds in which X is a methyl group and X and Y are oxygen atoms.

[0035] Specific examples of the compound represented by formula (1A) include the following:

[0036]

[0037] 1-1-2. Low Molecular Weight Compound B The compound represented by formula (1) may be a compound represented by formula (1B).

[0038] R in formula (1B) ２ ~R ４ and Z is R in formula (1). ２ ~R ４ and Z. When m is an integer of 2 or more, a plurality of R ２ may be the same or different. ３ may be the same as or different from each other.

[0039] In formula (1B), m is an integer of 2 or greater. The upper limit of m is not particularly limited, but can be, for example, 6 or less.

[0040] Among them, preferred examples of the compound represented by formula (1B) are those in which m is an integer of 2 to 4 and R ２ and R ３ are each an alkyl group or an aryl group, R ４ is an aliphatic group or an aromatic group, and Z is an oxygen atom or a sulfur atom; m is an integer of 2 to 3, and R ２ and R ３ are each an alkyl group having 3 or less carbon atoms, such as a methyl group, an ethyl group, or a propyl group, or a phenyl group, and R ４ is an aliphatic group or an aromatic group, and Z is an oxygen atom; m is an integer of 2 to 3, and R ２ and R ３ is a phenyl group, and R ４ is an aromatic group and Z is an oxygen atom; ２ and R ３ is a phenyl group 、 R ４ Particularly preferred are compounds in which is an aromatic group and Z is an oxygen atom.

[0041] Specific examples of the compound represented by formula (1B) include the following:

[0042]

[0043] 1-2. Polymer Compounds Polymer compounds are polymers containing structural units having a structure in which an acyloxy group is directly bonded to a triazine ring. When such polymer compounds are used as curing agents for epoxy compounds, the physical properties of the main chain structure can be reflected in the physical properties of the cured product of a curable composition containing the epoxy compound. Furthermore, compared to low molecular weight compounds, such polymer compounds are more likely to impart flexibility and the like to the cured product by controlling the crosslink density. The polymer compound may be a polymer (polymer compound A) containing structural units having a structure in which one acyloxy group is bonded to a triazine ring, or a polymer (polymer compound B) containing structural units having a structure in which two acyloxy groups are bonded to a triazine ring.

[0044] 1-2-1. Polymer Compound A One embodiment of the present invention relates to a polymer containing a structure represented by formula (2) or (3).

[0045] R in formulas (2) and (3) ２ , R ３ and R ６ is R in formula (1). ２ or R ３ and R are synonymous with each other. In formula (3), R is a group constituting the repeating unit of the polymer, and is an aliphatic group or an aromatic group. The aliphatic group or aromatic group may contain elements other than C and H, such as N, O, F, Cl, Br, S, P, or Si. That is, R is derived from a polymer having a carboxy group in the repeating unit. There is no limit to the number of (COO-) groups in the repeating unit. Examples of such polymers include poly(meth)acrylic acid and polyamic acid. X in formulas (2) and (3) is synonymous with X in formula (1).

[0046] In formula (2), R ５ is a divalent organic group. The divalent organic group is R ４ In this case, m=2.

[0047] In formulas (2) and (3), n is an integer of 2 or more. n is preferably an integer of 2 to 10,000, and more preferably an integer of 10 to 100.

[0048] Specific examples of polymers containing the structure represented by formula (2) include the following:

[0049] Specific examples of the polymer containing the structure represented by formula (3) include the following:

[0050] 1-2-2. Polymer Compound B One embodiment of the present invention relates to a polymer containing a structure represented by formula (4) or (5).

[0051] R in formula (4) ７ is R in formula (1). ２ or R ３ R in formula (5) ２ and R ３ is R in formula (1). ２ and R ３ X in formulas (4) and (5) has the same meaning as X in formula (1). In formula (4), R ８ is a divalent organic group. The divalent organic group is R ４ In formula (5), m is defined as 2. R in formula (5) is a group constituting the repeating unit of the polymer and is an aliphatic or aromatic group. The aliphatic or aromatic group may contain elements other than C and H, such as N, O, F, Cl, Br, S, P, or Si. That is, -[R(X)]n- is derived from a polymer having active hydrogen atoms, such as hydroxyl groups or amino groups, in the repeating unit. There is no limit to the number of active hydrogen atoms in the repeating unit. Examples of such polymers include polyphenols (including phenol novolac, cresol novolac, etc.), polyamines, etc. Furthermore, -[R(X)]n- may be a polymer derived from the polymerization of vinyl groups. In formulas (4) and (5), n is an integer of 2 or greater. n is preferably an integer of 2 to 10,000, and more preferably an integer of 10 to 100.

[0052] Specific examples of the compound represented by formula (4) include the following:

[0053] Specific examples of the compound represented by formula (5) include the following:

[0054] 1-3. Synthesis Method The above-mentioned active ester compound can be synthesized, for example, by reacting a chlorotriazine compound with a carboxylic acid compound in the presence of a tertiary amine compound in an organic solvent.

[0055] Reaction scheme (A) can be used to synthesize a compound having a structure in which one acyloxy group is bonded to a triazine ring (e.g., a compound represented by formula (1A) or a polymer having a structure represented by formula (2) or (3)). Reaction scheme (B) can be used to synthesize a compound having a structure in which two or more acyloxy groups are bonded to a triazine ring (e.g., a compound represented by formula (1B) or a polymer having a structure represented by formula (4) or (5)). Each case will be explained below.

[0056] (1) Synthesis of a compound represented by formula (1A) and a polymer having a structure represented by formula (2) or (3) First, a chlorotriazine compound is prepared (see the raw materials in reaction scheme (A)).

[0057] A chlorotriazine compound is obtained by reacting some of the three chlorine atoms of cyanuric chloride (2,4,6-trichloro-1,3,5-triazine) with a compound having a functional group containing active hydrogen (e.g., an amine, alcohol, thiol, etc.; represented by R-XH in the above reaction scheme). Reaction scheme (A) uses a compound in which two of the three chlorine atoms have been substituted with functional groups.

[0058] Examples of chlorotriazine compounds in which two of the three chlorine atoms have been substituted with functional groups include 2-chloro-4,6-dimethoxy-1,3,5-triazine, 2-chloro-4,6-diethoxy-1,3,5-triazine, 2-chloro-4-ethoxy-6-methoxy-1,3,5-triazine, and 2-chloro-4,6-diphenoxy-1,3,5-triazine.

[0059] Next, the remaining chlorine atoms of the chlorotriazine compound are reacted with a carboxylic acid compound in the presence of a tertiary amine compound to be substituted with acyloxy groups (see reaction scheme (A)).

[0060] Specifically, when N-methylmorpholine is used as the tertiary amine compound, the chlorotriazine compound and N-methylmorpholine readily react at 0°C to form an intermediate, 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMT-MM), which is then reacted with a carboxylic acid compound, thereby introducing an acyloxy group.

[0061] In the reaction scheme (A), for convenience, the carboxylic acid compound is represented by R ４ Although only one chlorotriazine compound is shown, the compound represented by formula (1A) can be obtained by reacting a polycarboxylic acid with an equivalent amount of the chlorotriazine compound as a carboxy group.

[0062] The polycarboxylic acid can be a polycarboxylic acid having a number of carboxy groups corresponding to m in formula (2A). For example, when m = 2, a dicarboxylic acid can be used, and when m = 3, a tricarboxylic acid can be used. Examples of dicarboxylic acids include phthalic acid, isophthalic acid, terephthalic acid, biphenyldicarboxylic acid, naphthalenedicarboxylic acid, oxydibenzoic acid, thiodibenzoic acid, dithiodibenzoic acid, carbonyldibenzoic acid, sulfonyldibenzoic acid, methylenedibenzoic acid, isopropylidenedibenzoic acid, hexafluoroisopropylidenedibenzoic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedicarboxylic acid, and dodecanedicarboxylic acid. Examples of tricarboxylic acids include trimesic acid and tricarballylic acid. From the perspective of improving curability, it is particularly preferable to use a polycarboxylic acid with m = 3 or more.

[0063] Examples of tertiary amine compounds include N-methylmorpholine and pyridine. These tertiary amine compounds not only react well with chlorotriazine compounds but also activate carboxylic acid compounds. A tertiary amine compound for activating carboxylic acid compounds may be used in combination with these tertiary amine compounds. Examples of such tertiary amine compounds include triethylamine.

[0064] Examples of the organic solvent include ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; aprotic polar solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N-methylcaprolactam, N,N-dimethylimidazolidone, tetramethylurea, pyridine, and γ-butyrolactone; nonpolar solvents such as toluene, hexane, and heptane; ether solvents such as tetrahydrofuran, diglyme, dioxane, and trioxane; and mixed solvents thereof.

[0065] The amount of the tertiary amine compound is preferably 1.0 to 1.2 molar equivalents relative to the carboxy group of the carboxylic acid compound. The amount of the tertiary amine compound includes both the tertiary amine compound for reacting with the chlorotriazine compound and the tertiary amine compound for activating the carboxylic acid. The amount of the carboxylic acid compound is preferably the same molar equivalent relative to the chloro group of the chlorotriazine compound. The temperature during the reaction between the chlorotriazine compound and the carboxylic acid compound is preferably, for example, −5 to 25° C.

[0066] When synthesizing a polymer having a structure represented by formula (2), for example, a chlorotriazine compound polymerized by polycondensation or the like may be used as a raw material. When synthesizing a polymer having a structure represented by formula (3), chlorotriazine may be reacted with a polymer having a carbonyl group in the side chain, such as polyacrylic acid, polymethacrylic acid, or polyamic acid.

[0067] (2) Synthesis of a compound represented by formula (1B) and a polymer having a structure represented by formula (4) or (5) First, a chlorotriazine compound in which one of the three chlorine atoms of cyanuric chloride is substituted with a functional group is prepared (see the raw materials in reaction scheme (B)).

[0068] Next, in the presence of a tertiary amine compound, the remaining two chlorine atoms of the chlorotriazine compound are each reacted with a carboxylic acid compound to be substituted with an acyloxy group (see reaction scheme (B)).

[0069] R in formulas (1) and (5) ２ or R ３Monocarboxylic acids can be used as the carboxylic acid compound that forms the side chain represented by the formula (I). The monocarboxylic acid may be an aliphatic or aromatic compound, or may be an unsaturated compound. Furthermore, other atoms may be bonded to the ring or on the ring. For example, saturated aliphatic monocarboxylic acids (e.g., formic acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, isovaleric acid, pivalic acid, lauric acid, myristic acid, palmitic acid, stearic acid), unsaturated aliphatic monocarboxylic acids or dicarboxylic acids (e.g., acrylic acid, propiolic acid, methacrylic acid, crotonic acid, isocrotonic acid, senecioic acid, tiglic acid, oleic acid, maleic acid, fumaric acid, citraconic acid, mesaconic acid), saturated or unsaturated carbocyclic carboxylic acids (e.g., camphoric acid, chrysanthemic acid), heterocyclic carboxylic acids (e.g., furancarboxylic acid, thiophenecarboxylic acid, pyrrolecarboxylic acid, pyrazinecarboxylic acid, nicotinic acid, isonicotinic acid, picolinic acid), aromatic carbocyclic carboxylic acids (e.g., benzoic acid, naphthalenecarboxylic acid, toluene acid), arylaliphatic saturated carboxylic acids, in particular arylpropionic acids (e.g., 2-phenylpropionic acid, 2-[4-(2-butyl)phenyl]propionic acid, 2-(3-benzoylphenyl)propionic acid, 2-(6-methoxy-2-phenyl)propionic acid, -naphthyl)propionic acid) or unsaturated acids (e.g., 2-phenylpropenoic acid, cinnamic acid), aliphatic or aromatic halogenated carboxylic acids (e.g., monofluoroacetic acid, difluoroacetic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monochloropropionic acid, α-bromopropionic acid, α-bromobutyric acid, trifluoroacetic acid, o-monofluorobenzoic acid, m-monofluorobenzoic acid, p-monofluorobenzoic acid, 2,3-difluorobenzoic acid, 2,4-difluorobenzoic acid, 2,5-difluorobenzoic acid, benzoic acid, 3,4-difluorobenzoic acid, 2,3,6-trifluorobenzoic acid, 2,4,5-trifluorobenzoic acid, 2,3,4,5-tetrafluorobenzoic acid, pentafluorobenzoic acid, α,α,α-trifluoro-o-toluic acid, α,α,α-trifluoro-m-toluic acid, α,α,α-trifluoro-p-toluic acid, o-monochlorobenzoic acid, m-monochlorobenzoic acid, p-monochlorobenzoic acid, 2,3-dichlorobenzoic acid, 2,4-dichlorobenzoic acid, 2,5-dichlorobenzoic acid, 2,6-dichlorobenzoic acid, 3,4-dichlorobenzoic acid, 3,5-dichlorobenzoic acid, 2,3,5-trichlorobenzoic acid, 2,3,6-trichlorobenzoic acid, 2-chloro-4,5-fluorobenzoic acid, 3-chloro-2,4,5-trifluorobenzoic acid, o-monobromobenzoic acid, m-monobromobenzoic acid, p-monobromobenzoic acid), etc.

[0070] The tertiary amine compound and organic solvent may be the same as those described above.

[0071] In addition, in Reaction Scheme (B), for convenience, a chlorotriazine compound having one chlorotriazine ring is shown. However, when synthesizing a compound represented by Formula (1B), a chlorotriazine compound having multiple chlorotriazine rings, which is obtained by reacting cyanuric chloride with a polyfunctional compound, may be used.

[0072] When synthesizing a polymer having a structure represented by formula (4), a dicarboxylic acid may be used as the carboxylic acid compound. For example, a dichlorotriazine compound and a dicarboxylic acid may be polycondensed in the presence of a tertiary amine. When synthesizing a polymer having a structure represented by formula (5), a chlorotriazine compound having a polymerizable reactive group such as a vinyl group introduced as a functional group may be used, or a chlorotriazine compound obtained by reacting cyanuric chloride with a polymer having an active hydrogen atom such as a hydroxy group or an amino group in a repeating unit may be used. For example, a chlorotriazine structure-containing polymer may be prepared by substituting one of the chlorine atoms of cyanuric chloride for the hydroxy group of phenol novolak or the like, and then the remaining chlorine atom of the chlorotriazine may be substituted with an acyloxy group.

[0073] Identification of the structure of the active ester compound １ H NMR measurement, １３ It can be measured by C NMR measurement, FT-IR measurement, and MS measurement.

[0074] ( １ H NMR measurement) １H NMR measurement can be performed using an NMR measurement device (e.g., JEOL JNM-ECZ600R / S1). Specifically, 20 mg of white powder and 0.5 mL of deuterated chloroform are added to a vial to prepare a sample for measurement, and measurement is performed under the conditions of a magnetic field strength of 600 MHz and an accumulation number of 8. The obtained results are normalized so that the resonance peak of tetramethylsilane in a deuterated solvent is 0.00 ppm.

[0075] ( １３ C NMR measurement) １３ C NMR measurement １ A sample is prepared in the same manner as in the H NMR measurement, and measurement is performed using the same apparatus under conditions of a magnetic field strength of 600 MHz and an accumulation count of 128. The obtained results are normalized so that the chloroform resonance peak is at 77.0 ppm. In the case of an active ester compound in which the X and Y atoms bonded to the triazine ring in the above formulas (1) to (6) are oxygen atoms and a hydrocarbon group is bonded to the oxygen atom, characteristic peaks derived from the triazine ring are observed at 171 and 174 ppm. In addition, one peak derived from the acyloxy group bonded to the triazine ring is observed between 160 and 170 ppm.

[0076] (FT-IR Measurement) Fourier transform infrared spectroscopy (FT-IR) measurement can be performed by the KBr method using an FT-IR device (e.g., FT / IR-4100 manufactured by JASCO). Specifically, 1.0 mg of the white powder and 100 mg of KBr powder are homogeneously mixed, then placed in a tablet press and tableted to prepare a measurement sample. Then, 25 measurements are performed with a resolution of 2 cm. －１ In the above formulas (1) to (6), in the case of an active ester compound in which the X and Y atoms bonded to the triazine ring are oxygen atoms and a hydrocarbon group is bonded to the oxygen atom, the spectrum is measured under the conditions of 1750 cm －１ The stretching vibration of the ester C=O is confirmed around 1360 cm －１ A strong peak due to triazine ring skeletal vibration is observed around this point.

[0077] (MS Measurement) Mass spectrometry (MS) is performed using atmospheric pressure chemical ionization (APCI) and field desorption mass spectrometry (FD-MS). For APCI, the white powder is dissolved in a solvent (acetone) and the sample solution is adjusted to a sample concentration of 10 mg / mL. The sample solution is then filtered and analyzed using a mass analyzer (e.g., Advion CMS expression) under the conditions of mobile phase: acetone, nebulizer gas: nitrogen, and "low temperature, low fragmentation." For FD-MS, the white powder is dissolved in tetrahydrofuran and the sample solution is adjusted to a sample concentration of 2 mg / mL. The sample solution is then filtered, and mass spectrometry can be performed using a mass spectrometer (e.g., a JEOL GC-TOFMS JMS-T100GCV) under the following conditions: measurement mode: eiFI FD+, cathode (emitter applied) voltage: -10 kV, detector voltage: 2.4 kV, and emitter current: 0 mA to 40 mA (increasing rate of 51.2 mA / min). Polyfunctional active ester compounds have large molecular weights, and in MS analysis, a peak corresponding to the molecular weight may not be obtained; however, the corresponding triazine oleate is detected as a fragment peak. For example, in the above formulas (1) to (6), if the X and Y atoms bonded to the triazine ring are oxygen atoms and an active ester compound in which a methyl group is bonded to the oxygen atom (an active ester compound in which a methoxy group is bonded to the triazine ring) has an m / z of 158 [2,4-dimethoxy-6-hydroxy-1,3,5-triazine + 1] ＋ The peaks due to

[0078] The above compounds can crosslink epoxy compounds by reacting with them even at low reaction temperatures, and therefore can be preferably used as curing agents for epoxy compounds.

[0079] 2. Curable Composition The curable composition according to one embodiment of the present invention contains an epoxy compound and a curing agent. The curable composition has the property of curing (solidifying) under specific conditions and is usually in the form of a liquid or varnish.

[0080] 2-1. Epoxy Compounds Epoxy compounds are compounds having two or more epoxy groups per molecule. The epoxy compound is not particularly limited and may be an alicyclic epoxy compound, a glycidyl-type epoxy compound including glycidyl ether, glycidyl amine, or glycidyl ester, or an internal epoxide. The glycidyl-type epoxy compound may be composed solely of aliphatic rings or may also contain an aromatic ring. In particular, alicyclic epoxy compounds are preferred in terms of the excellent balance of physical properties of the resulting cured product. The epoxy compound may be a low-molecular-weight compound or a high-molecular-weight compound. When the epoxy compound is a high-molecular-weight compound, it is sufficient that it has an epoxy group at the terminal or one or more epoxy groups in the repeating units constituting the polymer. Epoxy compounds may be used alone or in combination of two or more.

[0081] Alicyclic epoxy compounds are compounds obtained by epoxidizing unsaturated hydrocarbon compounds such as cyclohexene and cyclopentene ring-containing compounds with an oxidizing agent. Here, the term "alicyclic epoxy compounds" is used in a broad sense to include not only compounds with a cyclic skeleton but also compounds with epoxy groups introduced into the interior or terminal of a linear skeleton by oxidation of unsaturated groups. Examples of alicyclic epoxy compounds include 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-1-methylcyclohexyl-3,4-epoxy-1-methylhexanecarboxylate, 6-methyl-3,4-epoxycyclohexylmethyl-6-methyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxy-3-methylcyclohexylmethyl-3,4-epoxy-3-methylcyclohexanecarboxylate, 3,4-epoxy-5-methylcyclohexylmethyl-3,4-epoxy-5-methylcyclohexanecarboxylate, bis(3,4-epoxycyclohexylmethyl)adipate, methylenebis(3,4-epoxycyclohexane), propane-2,2-diyl-bis(3,4-epoxycyclohexane), 2,2-bis(3,4-epoxycyclohexyl)propane, dicyclopentadiene diepoxane, and the like. ide, 1,2:5,6-diepoxyhexahydroindan, dodecahydro-2,6:3,5-dimethano-2H-oxireno[3',4']cyclopenta[1',2':6,7]naphtho[2,3-b]oxirene, dodecahydro-2,6-methano-2H-oxireno[3',4']cyclopenta[1',2':6,7]naphtho[2,3-b]oxirene, ethylene bis(3,4-epoxycyclohexanecarboxylate), 1-epoxyethyl- Examples include 3,4-epoxycyclohexane, 1,2-epoxy-2-epoxyethylcyclohexane, 1,7-octadiene diepoxide, 2,3-epoxy-6,7-epoxyoctane, 1,3-bis[2-(7-oxabicyclo[4.1.0]heptan-3-yl)ethyl]-1,1,3,3-tetramethyldisiloxane, and 2,2'-(2,2,3,3,4,4,5,5-octafluorohexane-1,6-diyl)bis(oxirane).

[0082] Glycidyl epoxy compounds are compounds obtained by adding epichlorohydrin to compounds containing active hydrogen, such as phenols, amines, and carboxylic acids. When the functional group containing active hydrogen is a hydroxy group, the compound becomes a glycidyl ether compound; when it is an amino group, the compound becomes a glycidyl amine compound; and when it is a carboxy group, the compound becomes a glycidyl ester compound. There are no restrictions on the main skeleton. Examples of compounds containing hydroxy groups include aromatic structures such as bisphenol A, bisphenol F, bisphenol E, resorcinol, hydroquinone, catechol, tris(4-hydroxyphenyl)methane, phenol novolac, cresol novolac, and naphthol; structures consisting solely of aliphatic groups, such as hydrogenated bisphenol A, 1,2-dihydroxycyclohexane, and 1,3-dihydroxycyclohexane; linear or branched aliphatic polyhydric alcohols, and structures in which these are bonded directly or via ether groups. While the above compounds are compounds containing hydroxy groups, compounds containing amino or carboxy groups instead of hydroxy groups may also be used. Compounds with heterocyclic structures, such as isocyanuric acid, may also be used.

[0083] Internal epoxides are compounds that have an epoxy group other than at the molecular terminals, and can be obtained by a method of synthesizing by bonding an aliphatic compound with a compound having an internal epoxy group, or by a method of bonding an aliphatic compound with an unsaturated aliphatic compound having a carbon-carbon double bond within the molecule, and then bonding the internal carbon-carbon double bond with oxygen to introduce an epoxy group. Examples of internal epoxides include epoxidized linseed oil (product name: Adeka Cizer O-180A, manufactured by ADEKA Corporation), epoxidized rapeseed fatty acid isobutyl (product name: Adeka Cizer D-55, manufactured by ADEKA Corporation), and epoxidized fatty acid ester (product name: EpoCizer W-121, manufactured by DIC Corporation).

[0084] Among these, alicyclic epoxy compounds are particularly preferred as epoxy compounds to be combined with active ester compounds. Alicyclic epoxy compounds generally have lower reactivity than glycidyl-type epoxy compounds. Therefore, in order to cure an alicyclic epoxy compound, a higher reaction temperature is usually required than in the case of a glycidyl-type epoxy compound. In contrast, the above-mentioned active ester compounds have high reactivity, so they can react with alicyclic epoxy compounds at low temperatures, similar to the case of a glycidyl-type epoxy compound.

[0085] Furthermore, the reaction between an alicyclic epoxy compound and an active ester compound is more likely to be completed at a lower temperature than the reaction between other epoxy compounds and an active ester compound, and the reaction time can be shortened. The reason for this is not clear, but is presumed to be as follows.

[0086] For example, an example of reacting an epoxy compound with an active ester compound in the presence of an auxiliary will be described. When a glycidyl-based epoxy compound is used, the auxiliary not only reacts with the active ester compound but also with the glycidyl-based epoxy compound. On the other hand, when an alicyclic epoxy compound is used, the auxiliary reacts with the active ester compound but not with the alicyclic epoxy compound. As such, the reaction mechanisms differ between the use of an alicyclic epoxy compound and the use of a glycidyl-based epoxy compound, and the reaction scheme is simpler when an alicyclic epoxy compound is used than when a glycidyl-based epoxy compound is used. Therefore, the reaction between the alicyclic epoxy compound and the active ester compound is more likely to be completed at a lower temperature, allowing for a shorter reaction time.

[0087] 2-2. Curing Agent The curing agent includes a compound represented by the above formula (1) or a polymer having a structure represented by any one of formulas (2) to (5).

[0088] When any of the above compounds or polymers is used, the epoxy compound can be cured at a lower temperature than conventional active ester compounds. From the viewpoint of curing the epoxy compound at a lower temperature, the curing agent preferably contains a compound represented by formula (1A) or (1B), and more preferably contains a compound represented by formula (1A). Furthermore, from the viewpoint of more easily improving the physical properties of the cured product and more easily adjusting the crosslink density of the cured product, the curing agent preferably contains a polymer having a structure represented by any of formulas (2) to (5). The curing agents may be used alone or in combination of two or more.

[0089] From the viewpoint of enhancing the reactivity with epoxy compounds, among the above-mentioned active ester compounds, active ester compounds in which X and Y are —O— or —S— in the above formulas (1) to (5) are preferred. ２ and R ３ Preferably, at least one of R is an alkyl group or an aryl group. ２ and R ３ It is more preferable that at least one of R is an alkyl group having 3 or less carbon atoms, such as a methyl group, an ethyl group, or a propyl group, or a phenyl group. ２ and R ３ It is more preferable that at least one of the groups is a methyl group.

[0090] Thus, the reactivity of an active ester compound depends on the structure of the active ester compound, particularly R １ The reactivity of the above-mentioned active ester compound with the epoxy compound depends to some extent on the structures of R, X and Y. １ The reaction rate largely depends on the electron-withdrawing property of the compound and the stability of the 1,3,5-triazine-2-olate that is eliminated. For example, in the above reaction scheme, the lower the electron donating ability of X and Y of the active ester compound, the less likely it is that the electron density of the triazine ring will increase, and therefore the resulting 1,3,5-triazine-2-olate will be more likely to be stabilized and its reactivity will be more likely to increase. ２ , R ３The lower the electron donating property of X and Y, the lower the electron donating property of X and Y, and thus the reactivity is likely to be further increased. Specifically, when X and Y are -O- or -S-, the electron donating property of X and Y is lower than when they are -NR-, and therefore the reactivity of the active ester compound with the epoxy compound is likely to be higher. In other words, the reactivity of the active ester compound depends on X and Y.

[0091] Therefore, R ２ or R ３ Even if different, R １ If the active ester compounds have the same X and Y to some extent, they will exhibit the same reactivity. Also, if a low molecular weight compound exhibits a certain level of reactivity, the corresponding high molecular weight compound (polymer compound) will also exhibit almost the same reactivity. In other words, if the R of the active ester compound ２ or R ３ Even if R has a complex structure or a polymer structure, the R of the active ester compound １ When X and Y (particularly X and Y) are equivalent, they exhibit similar reactivity (reaction temperature).

[0092] The content of the curing agent in the curable composition is not particularly limited, but the equivalent ratio of the molar equivalent of the triazine ester group of the curing agent to the molar equivalent of the epoxy group of the epoxy compound is preferably 0.5 to 1.5, and more preferably 0.8 to 1.4.

[0093] 2-3. Other Components The curable composition may further contain an auxiliary (co-catalyst) such as a tertiary amine or an ammonium salt, as needed. However, by including an active ester compound, the curable composition can cure an epoxy compound without a co-catalyst. Therefore, the content of the auxiliary can be reduced or eliminated compared to conventional compositions. This is expected to improve the storage stability of the composition.

[0094] The auxiliary is not particularly limited as long as it promotes the reaction between the epoxy compound and the active ester compound, but is typically a curing accelerator such as a nucleophilic catalyst. Examples of curing accelerators include phosphorus-based curing accelerators, amine-based curing accelerators, and imidazole-based curing accelerators. Among these, amine-based curing accelerators are preferred from the viewpoint of further enhancing the reactivity between the active ester compound and the epoxy compound. Among the amine-based curing accelerators, those having a heterocyclic structure such as pyridine or pyrimidine are preferred, those having a pyridine structure are more preferred, and 4-dimethylaminopyridine is even more preferred.

[0095] The content of the auxiliary agent can be 5% by mass or less based on the epoxy compound.

[0096] 2-4. Uses of the Curable Composition The epoxy polymer obtained from the curable composition does not generate active hydrogen and therefore has excellent dielectric properties. Therefore, it can be used in electronic materials such as semiconductor package substrates, printed wiring boards, build-up films, and semiconductor encapsulation materials. It can also be used in other applications such as adhesives and paints.

[0097] 3. Method for Producing Curable Composition The curable composition can be produced by any method, for example, by dissolving and mixing the epoxy compound, the active ester compound, and, if necessary, the auxiliary and other components in a solvent, and then removing the solvent.

[0098] Here, the curable composition obtained by the above-mentioned production method is in the form of a varnish, and from the viewpoints of workability and storage stability, it is preferable that the varnish remains uniform even after the solvent is distilled off. Therefore, in order to obtain a uniform varnish, it is desirable to further increase the compatibility between the active ester compound and the epoxy compound.

[0099] In order to enhance the compatibility between the active ester compound and the epoxy compound, it is preferable to heat the active ester compound and the epoxy compound to a temperature equal to or higher than the reaction initiation temperature when producing a curable composition, thereby partially reacting them. This can further enhance the compatibility between the active ester compound and the epoxy compound, thereby more effectively preventing the precipitation of solids when, for example, distilling off the solvent. According to the above production method, a more highly compatible and uniform curable composition can be obtained, and therefore separation of the components of the curable composition can be more effectively prevented even when stored for a long period of time.

[0100] The heating temperature for partially reacting the active ester compound with the epoxy compound need only be equal to or higher than the temperature at which the epoxy compound and the active ester compound react. When the reaction temperature measured by DSC described below is Tp, the heating temperature is preferably, for example, Tp-30°C or higher and Tp+30°C or lower. A temperature of Tp-30°C or higher can further enhance the compatibility between the epoxy compound and the active ester compound. A temperature of Tp+30°C or lower can prevent the epoxy compound from curing too much and the composition from becoming gelatinous (gelation). Note that high heating temperatures tend to cause gelation, so if the heating temperature is high, gelation can be prevented by shortening the heating time. The heating temperature can be, for example, 70°C or higher and 190°C or lower.

[0101] The reaction temperature Tp can be measured by the following method: The epoxy compound and active ester compound to be used are mixed in a mortar until homogeneous. The resulting composition is subjected to DSC measurement, and the temperature is raised from 0°C to 200°C at a rate of 10°C / min. The peak top temperature of the first exothermic peak observed is read and taken as the reaction temperature Tp.

[0102] As described above, the active ester compound has a low reaction temperature with the epoxy compound, and therefore can react with the epoxy compound even at a low temperature at which the solvent does not volatilize, making the above method particularly effective.

[0103] 4. Cured Product The cured product of the curable composition does not contain hydroxyl groups that are generated upon ring-opening of the epoxy group of the active ester compound because the epoxy compound is cured by the active ester compound. Therefore, increases in moisture absorption and dielectric constant can be suppressed. Therefore, the curable composition can be used in various applications such as paints, adhesives, and electronic component materials.

[0104] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0105] 1. Synthesis of Active Ester Compound (Synthesis of Compound F) 200 mL of tetrahydrofuran (THF) (dehydrated) and 12.6 g (0.072 mol, 249 parts by mass) of 2-chloro-4,6-dimethoxy-1,3,5-triazine were added to a 500 mL three-neck flask equipped with a 200 mL dropping funnel, a calcium chloride tube, a magnetic stirrer, and a thermometer, and the mixture was dissolved at a temperature of 25°C. The mixture was then cooled to 0°C to obtain a first solution. 50 mL of THF (dehydrated) and 8.69 g (0.086 mol, 172 parts by mass) of N-methylmorpholine were added to a separate beaker and dissolved to obtain a second solution. The second solution was added dropwise to and mixed with the first solution, taking care not to allow the temperature of the first solution to exceed 5°C, to obtain a mixed solution. Next, 70 mL of THF (dehydrated) and 5.06 g (0.024 mol, 100 parts by mass) of 1,3,5-benzenetricarboxylic acid were added to another beaker and dissolved to obtain a third solution. The third solution was added dropwise to the mixed solution so that the temperature of the mixed solution did not exceed 5°C, obtaining a reaction solution. The reaction solution was stirred for 1 hour while maintaining the temperature at 0°C. After stirring, the reaction solution was filtered to remove precipitated salts. The filtrate was transferred to a separatory funnel and washed three times with 120 mL of 10% saline solution adjusted to pH 2 with hydrochloric acid. The filtrate was further washed once with 100 mL of saturated saline, and the washed filtrate was separated into an Erlenmeyer flask. An appropriate amount of magnesium sulfate was added to the mixture to dehydrate it, and then filtered. The solvent was removed from the filtrate using an evaporator, and the residue was dried under reduced pressure in a desiccator at 25° C. for 21 hours to obtain 8.12 g of a white powder (compound F) in a yield of 51.4%.

[0106] (Identification) The white powder was subjected to the following measurements to identify its structure.

[0107] ( １ H NMR measurement, １３ C NMR measurement) １ H NMR measurements were performed using an NMR device (JNM-ECZ600R / S1 manufactured by JEOL). More specifically, 20 mg of the white powder and 0.5 mL of deuterated chloroform were added to a vial to prepare a sample for measurement, and measurements were performed under the following conditions: magnetic field strength: 600 MHz, number of accumulations: 8. The results obtained were normalized so that the resonance peak of tetramethylsilane in a deuterated solvent was 0.00 ppm. １３ C NMR measurement １ Samples were prepared in the same manner as in the H NMR measurements, and measurements were performed using the same instrument under the conditions of magnetic field strength: 600 MHz, and number of accumulations: 128. The results were normalized so that the chloroform resonance peak was at 77.0 ppm. In each measurement, the chemical shift delta δ was expressed in ppm. The coupling constant J was expressed in hertz (Hz). The notations d and t represent d (doublet) and t (triplet), respectively.

[0108] (FT-IR Measurement) Fourier transform infrared spectroscopy (FT-IR) measurement was carried out by the KBr method using an FT-IR device (FT / IR-4100 manufactured by JASCO). More specifically, 1.0 mg of the white powder and 100 mg of KBr powder were homogeneously mixed, then placed in a tablet press and tableted to prepare a measurement sample. Thereafter, 25 integration times and a resolution of 2 cm were used. －１ The spectrum was measured under the following conditions.

[0109] (MS Measurement) Mass spectrometry (MS: Mass Spectrometry) was carried out by field desorption mass spectrometry (FD-MS: Field Desorption-Mass Spectroscopy). For FD-MS, the white powder was dissolved in tetrahydrofuran, and the sample solution was adjusted so that the sample concentration was 2 mg / mL. The sample solution was then filtered, and using a mass spectrometer (JEOL GC-TOFMS JMS-T100GCV), the measurement mode was eiFI FD+, the cathode (emitter applied) voltage was -10 kV, the detector voltage was 2.4 kV, and the emitter current was 0 mA to 40 mA (51.2 mA / min increase rate).

[0110] (Results) White powder １ H NMR measurement results, １３ The C NMR measurement results, FT-IR measurement results, and MS measurement results are as follows. １ H NMR (600MHz, DMSO-d6, TMS): δ = 8.67 (s, 3H), 3.91 (s, 6H) １３ C NMR (150 MHz, DMSO-d6): δ = 173.5 (triazine), 168.5 (triazine), 166.4 (triazine), 157.5 (C=O), 133.8 (phenyl group), 132.4 (phenyl group), 130.9 (phenyl group), 55.7 (CH ３ ) FT-IR (KBr, cm －１ ): 3069 (Ar-H stretching vibration), 2954 (CH ３ stretching vibration), 1722 (C═O stretching vibration), 1600 (benzene ring skeletal vibration), 1540 (triazine ring skeletal vibration), 1241 (phenyl group skeletal vibration), 1099 (phenyl group skeletal vibration) MS: m / z 628.14 [M+H ＋ ] ＋ From these analytical results, it was confirmed that the white powder (compound F) was a triazine compound represented by the following formula:

[0111] (Synthesis of Compound H) Into a 50 mL three-neck flask equipped with a 50 mL dropping funnel, a magnetic stirrer, and a thermometer, 20 mL of THF (dehydrated), 1.93 g (0.010 mol, 150 parts by mass) of 2-chloro-4,6-di(p-methoxybenzenethio)-1,3,5-triazine, and 1.29 g of 4,4'-dicarboxydiphenyl ether (0.005 mol, 100 parts by mass) were added and dissolved at a temperature of 25°C, followed by cooling to 0°C to obtain a first solution. Into a separate beaker, 50 mL of THF (dehydrated) and 1.52 g (0.015 mol, 118 parts by mass) of N-methylmorpholine were added and dissolved to obtain a second solution. The second solution was added dropwise to and mixed with the first solution, ensuring that the temperature of the first solution did not exceed 5°C, to obtain a mixed solution. The reaction solution was stirred for 1 hour while maintaining the temperature at 0°C, and then stirred for 1 hour at 25°C. After stirring, the reaction solution was filtered to remove precipitated salts. The solvent was removed from the filtrate using an evaporator, and 20 mL of chloroform was added to the residue to dissolve it. The solution was transferred to a separatory funnel and washed twice with 20 mL of water. The resulting organic layer was dried over anhydrous magnesium sulfate, and the solid was filtered off and the solvent was removed using an evaporator to obtain a yellow-white powder (Compound H) in a yield of 84.1%.

[0112] (Synthesis of Compounds G, and I to U) Compounds G and I to Q were synthesized in the same manner as compound H, except that the types and amounts of raw materials were changed. Compounds R to U were synthesized in the same manner as compound F, except that the types and amounts of raw materials were changed.

[0113] (TAB: triacetoxybenzene)

[0114] (Synthesis of Reference Compound) 150 mL of THF (dehydrated) and 7.5 g (0.043 mol, 144 parts by mass) of 2-chloro-4,6-dimethoxy-1,3,5-triazine were added to a 500 mL three-neck flask equipped with a 200 mL dropping funnel, a calcium chloride tube, a magnetic stirrer, and a thermometer. The mixture was dissolved at a temperature of 25°C and then cooled to 0°C to obtain a first solution. 50 mL of THF (dehydrated), 5.2 g (0.043 mol, 100 parts by mass) of benzoic acid, and 5.15 g (0.051 mol, 99 parts by mass) of N-methylmorpholine were added to a separate beaker and dissolved to obtain a second solution. The second solution was added dropwise to and mixed with the first solution, ensuring that the temperature of the first solution did not exceed 5°C, to obtain a reaction solution. The reaction solution was stirred for 1 hour while maintaining the temperature at 0°C. After stirring, the reaction solution was filtered while maintaining the temperature at 0°C to remove precipitated salts. The filtrate was transferred to a separatory funnel and washed three times with 200 mL of 10% saline solution adjusted to pH 2 with hydrochloric acid. Finally, it was washed once with 200 mL of saturated saline solution, and the filtrate after washing was separated into an Erlenmeyer flask. An appropriate amount of magnesium sulfate was added to the filtrate for dehydration, followed by filtration. The solvent was removed from the filtrate using an evaporator, and the filtrate was dried under reduced pressure in a desiccator at 25°C for 96 hours, yielding 8.70 g of white powder (2,4-dimethoxy-6-benzoyloxy-1,3,5-triazine, reference compound) in a yield of 78.4%.

[0115] 2. Evaluation of Active Ester Compounds (Example 1) Compound F was added to epoxy compound I (jER828 manufactured by Mitsubishi Chemical) so that the molar equivalent of the ester group in compound F was the same as that of the epoxy group in epoxy compound I. Furthermore, dimethylaminopyridine (DMAP) was added as an auxiliary agent in an amount corresponding to 1% by mass of the entire composition (2.1 parts by mass relative to the epoxy compound), and the mixture was mixed in a mortar until uniform, thereby obtaining a composition.

[0116] (1) Evaluation of reactivity 10 mg of the obtained composition was placed in an aluminum pan, and the temperature was raised from 0°C to 200°C at a rate of 10°C / min under a nitrogen stream using a differential scanning calorimeter (DSC 3+ manufactured by METTLER TOLEDO). The peak top temperature of the first exothermic peak observed was read and used as the reaction temperature. The reaction temperature was 110°C.

[0117] (2) Sensory evaluation of heated product The obtained composition was poured into a silicone mold and heated in a thermostatic bath at 130°C for 1 hour. The obtained heated product was evaluated for hardening by sensory evaluation according to the following criteria: A: No deformation due to pressing, and the surface is not sticky (hardened) B: No deformation due to pressing, but the surface is sticky (insufficient hardening) C: Deformation due to pressing, and the surface is sticky (insufficient hardening)

[0118] Example 2 A composition was obtained in the same manner as in Example 1, except that DMAP was not added, and then the reaction temperature and the cured product were subjected to sensory evaluation. The reaction temperature was 123°C.

[0119] Example 3 A composition was obtained in the same manner as in Example 1, except that epoxy compound II (Celloxide 2021P manufactured by Daicel Corporation, an epoxy compound represented by the following formula) was used instead of epoxy compound I (jER828 manufactured by Mitsubishi Chemical Corporation), and then the composition was evaluated in the same manner.

[0120] Examples 4, 6, 10 to 20, 22 Compositions were obtained in the same manner as in Example 1 except that the compounds shown in Table 1 were used instead of Compound F, and then the same evaluations were carried out.

[0121] Examples 5 and 7 Compositions were obtained in the same manner as in Example 2, except that the compounds shown in Table 1 were used instead of Compound F, and then the same evaluations were carried out.

[0122] Example 8 A composition was obtained in the same manner as in Example 3, except that the compound shown in Table 1 was used instead of compound F, and then the same evaluation was carried out.

[0123] Example 9 A composition was obtained in the same manner as in Example 8, except that DMAP was not added, and then the same evaluation was carried out.

[0124] Example 21 A composition was obtained in the same manner as in Example 1, except that epoxy compound III (EPICLON 830 (Bis-F) manufactured by DIC Corporation) was used instead of epoxy compound I (jER828 manufactured by Mitsubishi Chemical Corporation) and compound T was used instead of compound F, and then the same evaluation was carried out.

[0125] Comparative Example 1 A composition was obtained in the same manner as in Example 1 except that TAB (triacetoxybenzene) was used instead of Compound F, and then the composition was evaluated in the same manner.

[0126] Comparative Example 2 A composition was obtained in the same manner as in Example 3, except that TAB (triacetoxybenzene) was used instead of Compound F, and then the composition was evaluated in the same manner.

[0127] Reference Example 1 A composition was obtained in the same manner as in Example 1, except that a reference compound was used instead of Compound 1. The reaction temperature was 132°C.

[0128] (Evaluation Results) The evaluation results of Examples 1 to 22 and Comparative Examples 1 and 2 are shown in Table 1.

[0129] (Discussion) (1) Reactivity As shown in Table 1, compounds F to U (Examples 1 to 22) have lower peak temperatures than TAB (Comparative Examples 1 and 2), and are found to react with epoxy compounds at lower temperatures.

[0130] FIG. 1 is a graph showing the results of DSC measurement. For comparison, the results of DSC measurement for Compound 2 are also shown. As shown in FIG. 1, it can be seen that Compound F (Example 1) reacts with the epoxy compound at an even lower reaction temperature than the reference compound (Reference Example 1). This indicates that Compound F exhibits even higher reactivity than the reference compound. It can also be seen that Compound F exhibits good reactivity even without the use of the co-catalyst DMAP (Example 2).

[0131] Fig. 2A is a graph showing the DSC measurement results of compound F, Fig. 2B is a graph showing the DSC measurement results of compound H, and Fig. 3 is a graph showing the DSC measurement results of TAB. Each figure shows the results of 1) the compound alone, 2) the case where the compound was reacted with a bisphenol A epoxy compound, and 3) the case where the compound was reacted with a bisphenol A epoxy compound in the presence of DMAP. Comparing the case of 3), TAB has a reaction peak around 170°C (see Fig. 3), whereas compound H has a reaction peak around 130°C and compound F has a reaction peak around 110°C (see Figs. 2A and 2B), indicating that the reaction temperatures are low in both cases.

[0132] (2) Curability As shown in Table 1, the sensory evaluation of the heated products of Examples 1 to 22 was A, confirming that cured products were obtained.

[0133] Fig. 4 shows a photograph of the heated product of Example 1. As shown in Fig. 4, the sensory evaluation of the obtained heated product was A, and it was confirmed that a cured product was obtained.

[0134] From the above results, it was confirmed that the compound of the present invention can cure glycidyl ether type epoxy base resins and alicyclic epoxy base resins.

[0135] (3) Differences Depending on the Type of Epoxy Compound Figure 5 is a graph showing the results of DSC measurement of compound H (Examples 6 and 8) with different types of epoxy compounds. As shown in Figure 5, the reaction temperature when reacted with epoxy compound II (alicyclic epoxy compound) is almost the same as the reaction temperature when reacted with epoxy compound I (glycidyl-based epoxy compound). It is also clear that the peak end position when reacted with epoxy compound II (alicyclic epoxy compound) is shifted to a lower temperature than the peak end position when reacted with epoxy compound I (glycidyl-based epoxy compound). These findings indicate that the reaction time can be further shortened by combining an alicyclic epoxy compound with an active ester compound.

[0136] 3. Compatibility Study 3-1. Preparation of Curable Composition 100 parts by mass of dimethylacetamide (DMAc) was placed in a vial, followed by 10 parts by mass of compound F (reaction temperature Tp = 110°C), 8.1 parts by mass of epoxy compound I, and 0.2 parts by mass of DMAP. The mixture was ultrasonically dispersed at a temperature of just under 50°C for 1 hour, but none of the components dissolved. The resulting composition was then heated under the temperatures and times specified in conditions 1 to 5 to form a homogeneous solution. Condition 1: 100°C, 30 minutes; Condition 2: 100°C, 60 minutes; Condition 3: 100°C, 120 minutes; Condition 4: 100°C, 180 minutes; Condition 5: 80°C, 120 minutes. The solution was then dried under reduced pressure at 40°C for 16 hours, and the state after drying for 2 hours was photographed and visually observed.

[0137] 3-2. Evaluation Figure 6 is a photograph of the state of each curable composition after drying, taken from directly above the bottom of the vial. As shown in Figure 6, after 2 hours of drying, slight solid precipitates were observed under conditions 1, 2, and 5, whereas no solid precipitates were observed under conditions 3 and 4. In particular, under condition 4, no solid precipitates were observed even after 16 hours of drying. These findings indicate that heating at a temperature equal to or higher than the reaction temperature for a predetermined period of time further enhances the compatibility between the epoxy compound and the active ester compound.

[0138] This application claims priority based on Japanese Patent Application No. 2023-223596, filed December 28, 2023. The contents of the specification and drawings of that application are incorporated herein by reference in their entirety.

[0139] The compound and polymer of the present invention can react with an epoxy compound at a low reaction temperature and can suppress the generation of hydroxyl groups, and therefore can be preferably used as a curing agent for an epoxy compound.

Claims

1. A compound represented by the following formula (1). (In formula (1), R ２ and R ３ are each a monovalent organic group, R ４ is an m-valent organic group, m is an integer of 1 or more, when m = 1, two of X, Y and Z are carbonyloxy bonds, and the rest are an oxygen atom, -NR- (R is a substituent) or a sulfur atom, when m = 2 or more, at least one of X, Y and Z is a carbonyloxy bond, and the rest are an oxygen atom, -NR- (R is a substituent) or a sulfur atom) 2. The compound according to claim 1, wherein m is an integer of 2 or more, Z is a carbonyloxy bond, and X and Y are each an oxygen atom, -NR- or a sulfur atom.

3. The compound according to claim 1, wherein m is an integer of 2 or more, X and Y are each a carbonyloxy bond, and Z is an oxygen atom, -NR- or a sulfur atom.

4. A polymer having a structure represented by the following formula (2) or (3). (In formula (2) and (3), R ２、 R ３ and R ６ are each a monovalent organic group, R ５ is a divalent organic group, R is a group constituting the repeating unit of the polymer, X and Y are each an oxygen atom, —NR— (R is a substituent) or a sulfur atom, and n is an integer of 2 or more.) 5. A polymer having a structure represented by the following formula (4) or (5). (In formula (4) and (5), R ２、 R ３ and R ７ are each a monovalent organic group, R ８ is a divalent organic group, R is a group constituting the repeating unit of the polymer, X is an oxygen atom, —NR— (R is a substituent) or a sulfur atom, and n is an integer of 2 or more.) 6. A curing agent for an epoxy compound, comprising the compound according to any one of claims 1 to 3 and / or the polymer according to claim 4 or 5.

7. A curable composition comprising an epoxy compound and the curing agent according to claim 6.

8. The curable composition according to claim 7, wherein the epoxy compound is an alicyclic epoxy compound.

9. A cured product of the curable composition according to claim 8.

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