Epoxy resin composition, cured product thereof, and disassembly method

Abstract

Provided are: an epoxy resin composition which has excellent adhesiveness, flexibility, and removability in a cured product despite being an epoxy resin composition; a cured product of the epoxy resin composition; and a disassembly method using a detachable adhesive material. An epoxy resin composition according to an embodiment of the present invention contains (A) an epoxy resin having a specific structure and an epoxy equivalent weight of 500-10,000 g / eq, (B) an epoxy resin having an epoxy equivalent weight of 100-300 g / eq, (C) a glycidyl ether group-containing compound having a molecular weight of less than 1000, and (D) thermally expandable particles. The glycidyl ether group-containing compound (C) has a specific structure containing a reversible bond.

Description

TECHNICAL FIELD

[0001] The present application relates to an epoxy resin composition, a cured product thereof, and a disassembly method using a disassembly adhesive.

[0002] This application claims priority based on Japanese Patent Application No. 2023-195047 filed on November 16, 2023, the contents of which are hereby incorporated by reference. BACKGROUND

[0003] The cured product obtained from an epoxy resin is excellent in heat resistance, mechanical strength, electrical properties, adhesiveness, and the like, and is an essential material in various fields such as electrical / electronics, paints, adhesives, and the like.

[0004] On the other hand, for a cured product using a thermosetting resin such as an epoxy resin, a low long-term reliability can be cited, and for example, if the cured product of the epoxy resin is oxidized and deteriorated, there is a case where a crack is generated.

[0005] In addition, the cured product obtained by once curing a thermosetting resin such as an epoxy resin cannot be dissolved in a solvent (insoluble), and in addition, does not melt even at a high temperature (infusible). Therefore, there is a lack of recyclability, reusability, and the cured product after use becomes a waste, and thus, it is a problem to achieve reduction of waste and reduction of environmental load.

[0006] Therefore, for a cured product using an epoxy resin or the like, it is required to solve the problems of long life and reduction of waste, and in order to solve these problems, it is considered to be effective to impart easy disassembly to the cured product.

[0007] For example, as a technology related to weight reduction of automobiles / airplanes and the like, high performance of an adhesive for a structural material is necessary. On the other hand, achievement of high adhesion performance also becomes a major factor in producing products that are difficult to recycle, and disassembly after use, reusability is limited. Against the background of the recent rise in environmental awareness, it has also become important to develop an adhesive that maintains high adhesion performance while being easily peeled off after use. Under such a background, development of an easy disassembly adhesive is actively being carried out. In general, in most cases, heat melting of a thermoplastic resin is utilized, but in recent years, a technology has also been proposed in which a heat-expandable material and a heat-decomposable compound are mixed in advance in a thermosetting resin, and mainly thermal energy is imparted after use, thereby reducing the adhesion force to peel off (for example, refer to Patent Documents 1 and 2).

[0008] PRIOR ART DOCUMENTS

[0009] PATENT DOCUMENTS

[0010] Patent Document 1: Japanese Patent Application Laid-Open No. 2003-286464

[0011] Patent Document 2: Japanese Patent Application Publication No. 2013-256557 Summary of the Invention

[0012] The problem that the invention aims to solve

[0013] However, in the technology of the aforementioned Patent Document 1, conventional epoxy resin compositions are basically used as adhesives. Therefore, it is difficult to fully exhibit the foaming caused by the thermally expanding material within the cured product (adhesive layer). As a result, sometimes the peelability is insufficient, or the adhesive layer cannot be cleanly removed due to its hardness and brittleness.

[0014] Furthermore, the technology in the aforementioned Patent Document 2 contains a thermally decomposable compound. Therefore, precise control of the heating temperature during the curing reaction is required, resulting in significant operational complexity. Especially when using a metal substrate with high thermal conductivity, the possibility of unpredictable overheating of the adhesive and subsequent adverse effects cannot be ruled out. Additionally, the disassembled adhesive is discarded, and although the substrate itself is recyclable, overall recyclability remains a challenge.

[0015] Therefore, the objective of this invention is to provide an epoxy resin composition and its cured product, as well as a disassembly method using a removable adhesive material, which provides an epoxy resin composition that, although a curable resin, has excellent adhesion, flexibility, and removability of the cured product.

[0016] Methods for solving problems

[0017] The inventors conducted in-depth research and found that by using a compound (C) containing a glycidyl ether group with a specific structure and an epoxy resin with a specific structure, and by incorporating thermally expandable particles into the resin composition, the aforementioned problems can be solved, thus completing the invention.

[0018] That is, the present invention includes the following methods.

[0019] [1] An epoxy resin composition, characterized in that it contains:

[0020] The epoxy resin (A) with an epoxy equivalent of 500~10,000 g / eq is represented by the following general formula (1).

[0021] Epoxy resin (B) with an epoxy equivalent of 100~300 g / eq

[0022] The following general formula (4) represents compounds (C) containing glycidyl ether groups with a molecular weight less than 1000, and

[0023] Thermally expandable particles (D),

[0024] [Chemistry 1]

[0025]

[0026] In formula (1), Ar is an independent structure containing an aromatic ring with an unsubstituted or substituent group.

[0027] X is a structural unit represented by the following general formula (2), and Y is a structural unit represented by the following general formula (3).

[0028] [Chemistry 2]

[0029]

[0030] In equations (2) and (3), Ar is the same as described above.

[0031] R1 and R2 are each independently a hydrogen atom, a methyl group, or an ethyl group.

[0032] R' is a divalent hydrocarbon group with 2 to 12 carbon atoms.

[0033] R3, R4, R7, and R8 are each independently a hydroxyl group, a glycidyl ether group, or a 2-methylglycidyl ether group.

[0034] R5, R6, R9, R 10 Each can be independently a hydrogen atom or a methyl group.

[0035] n1 is an integer between 4 and 16.

[0036] n² is the average value of the repeating units and ranges from 2 to 30.

[0037] R 11 R 12 Each is independently a glycidyl ether group or a 2-methylglycidyl ether group.

[0038] R 13 R 14 Each can be independently a hydroxyl, glycidyl ether, or 2-methylglycidyl ether group.

[0039] R 15 R 16 It can be a hydrogen atom or a methyl group.

[0040] m1, m2, p1, p2, and q are the average values ​​of repeated samples.

[0041] m1 and m2 are each independently between 0 and 25, and m1 + m2 ≥ 1.

[0042] p1 and p2 are each independently represented by a value between 0 and 5.

[0043] q is 0.5~5. The bond between X represented by the aforementioned general formula (2) and Y represented by the aforementioned general formula (3) can be random or block. The total number of each structural unit X and Y present in a molecule is represented by m1 and m2, respectively.

[0044] [Chemistry 3]

[0045]

[0046] In equation (4), m3 is an integer from 1 to 4. 1 For any of the structures represented by the following equation (5), Z 3 For any of the structures represented by the following formula (6), a molecule may have multiple structures, which may be the same or different.

[0047] [Chemistry 4]

[0048]

[0049] [The aromatic ring in formula (5) can be substituted or unsubstituted, and * indicates a bonding site. G is glycidyl or 2-methylglycidyl, and -OG on the naphthalene ring in the formula indicates that it can be bonded at any location.]

[0050] [Chemistry 5]

[0051]

[0052] (In formula (6), R' is a divalent hydrocarbon group with 2 to 12 carbon atoms, R” is independently a hydrogen atom, methyl or ethyl, n1 is an integer from 1 to 30, n2 is the average of the number of repetitions and is 0.5 to 8, and * indicates a bonding point.)

[0053] [2] The epoxy resin composition according to [1] includes a compound (I) that is reactive with the aforementioned compound (C) containing glycidyl ether group as an essential component.

[0054] [3] According to the epoxy resin composition of [2], wherein the compound (I) that is reactive with the aforementioned compound (C) containing glycidyl ether group is a compound containing hydroxyl group or a compound containing amine group.

[0055] [4] The epoxy resin composition according to any one of [1] to [3], wherein the concentration of reversible bonds in the compound (C) containing glycidyl ether group is 0.10 mmol / g or more relative to the total mass of the curable components in the aforementioned epoxy resin composition.

[0056] [5] The epoxy resin composition according to any one of [1] to [4], wherein the mass ratio (A): (B) of the aforementioned epoxy resin (A) to the aforementioned epoxy resin (B) is 90:10 to 10:90.

[0057] [6] The epoxy resin composition according to any one of [1] to [5], wherein the aforementioned thermally expandable particle (D) is at least one selected from the group consisting of thermally expandable microcapsules and expanded graphite.

[0058] [7] The epoxy resin composition according to any one of [1] to [6], wherein the proportion of the aforementioned thermally expandable particle (D) used is in the range of 3 to 40 parts by mass relative to a total of 100 parts by mass of the aforementioned epoxy resin (A) and the aforementioned epoxy resin (B).

[0059] [8] A cured product which is formed by curing any one of the epoxy resin compositions described in [2] to [7].

[0060] [9] A laminate having a substrate and a layer comprising the cured material described in [8].

[0061]

[10] A heat-resistant component comprising the cured product described in [8].

[0062]

[11] A detachable adhesive material comprising any one of the epoxy resin compositions described in [2] to [7].

[0063]

[12] A disassembly method, which is a disassembly method using the removable adhesive material described in

[11] , comprising:

[0064] The bonding process involves attaching the aforementioned detachable adhesive material to the surface of the object to be bonded, thereby bonding the material to the object.

[0065] The curing process involves curing the aforementioned removable adhesive material to obtain a cured product.

[0066] The heat treatment process involves subjecting the aforementioned cured material to heat dissociation of the reversible bonds contained in the aforementioned general formula (4) derived from the aforementioned compound (C) containing glycidyl ether groups, and to heat treatment that expands the aforementioned thermally expandable particles (D).

[0067] The disassembly process involves separating the aforementioned adhered material from the aforementioned cured material.

[0068]

[13] According to the disassembly method described in

[12] , the process further includes a cooling step of cooling the heat-treated solidified material to room temperature after the heat treatment step and before the disassembly step.

[0069] Invention Effects

[0070] According to the present invention, epoxy resin compositions with excellent adhesion, flexibility and disassembly properties of cured products can be provided. Detailed Implementation

[0071] Next, the methods for implementing the present invention will be described in detail. It should be understood that the present invention is not limited to the following embodiments, and design changes, modifications, etc., can be appropriately made based on the ordinary knowledge of those skilled in the art without departing from the spirit of the present invention.

[0072] (Epoxy resin composition)

[0073] The epoxy resin composition of one aspect (this embodiment) of the present invention is the following epoxy resin composition, characterized in that it contains: epoxy resin (A) with an epoxy equivalent of 500 to 10,000 g / eq represented by the above general formula (1), epoxy resin (B) with an epoxy equivalent of 100 to 300 g / eq, compound (C) containing glycidyl ether group with a molecular weight of less than 1000 represented by the above general formula (4), and thermally expandable particles (D).

[0074] The epoxy resin composition of this embodiment preferably further includes a compound (I) that is reactive with the aforementioned compound (C) containing glycidyl ether groups. The epoxy resin composition of this embodiment may also include, as needed, other epoxy resins besides the aforementioned epoxy resin (A), epoxy resin (B), and the aforementioned compound (C) containing glycidyl ether groups. Furthermore, the epoxy resin composition of this embodiment may also include, as needed, a curing accelerator, other thermosetting resins, thermoplastic resins, non-halogenated flame retardants, fillers not belonging to the aforementioned thermally expanding particles (D) of this embodiment, or a dispersion medium.

[0075] The following is a detailed explanation of each ingredient.

[0076] [Epoxy Resin (A)]

[0077] The epoxy resin (A) contained in the epoxy resin composition of this embodiment is an epoxy resin with an epoxy equivalent of 500 to 10,000 g / eq, represented by the following general formula (1).

[0078] [Chemistry 6]

[0079]

[0080] In formula (1), Ar is an independent structure containing an aromatic ring with an unsubstituted or substituent group.

[0081] X is a structural unit represented by the following general formula (2), and Y is a structural unit represented by the following general formula (3).

[0082] [Chemistry 7]

[0083]

[0084] In equations (2) and (3), Ar is the same as described above.

[0085] R1 and R2 are each independently a hydrogen atom, a methyl group, or an ethyl group.

[0086] R' is a divalent hydrocarbon group with 2 to 12 carbon atoms.

[0087] R3, R4, R7, and R8 are each independently a hydroxyl group, a glycidyl ether group, or a 2-methylglycidyl ether group.

[0088] R5, R6, R9, R 10 Each can be independently a hydrogen atom or a methyl group.

[0089] n1 is an integer between 4 and 16.

[0090] n² is the average value of the repeating units and ranges from 2 to 30.

[0091] R 11 R 12 Each is independently a glycidyl ether group or a 2-methylglycidyl ether group.

[0092] R 13 R 14 Each can be independently a hydroxyl, glycidyl ether, or 2-methylglycidyl ether group.

[0093] R 15 R 16 It can be a hydrogen atom or a methyl group.

[0094] m1, m2, p1, p2, and q are the average values ​​of repeated samples.

[0095] m1 and m2 are each independently between 0 and 25, and m1 + m2 ≥ 1.

[0096] p1 and p2 are each independently represented by a value between 0 and 5.

[0097] q is 0.5~5. The bond between X represented by the aforementioned general formula (2) and Y represented by the aforementioned general formula (3) can be random or block. The total number of each structural unit X and Y present in a molecule is represented by m1 and m2, respectively.

[0098] It is an epoxy resin containing structural unit X represented by general formula (2) and / or structural unit Y represented by general formula (3) in the above structure. Due to the presence of alkylene chains or polyether chains in each structural unit, the cured product exhibits high flexibility. In particular, based on the flexibility of the alkylene chains, when used as an adhesive, it can follow the thermal expansion of the substrate. In addition, the polyether chains have the effect of reducing the viscosity of the epoxy resin (A) itself. From this point of view, it helps to improve the coatability and processability of the epoxy resin composition.

[0099] In the aforementioned epoxy resin (A), structural units X and Y can be present individually, or both structural units X and Y can be present in a single molecule. In this case, X and Y can be block bonds or random bonds, and the total number of structural units X and Y contained in a single molecule is represented as m1 and m2, respectively.

[0100] Ar in general formula (1) representing the aforementioned epoxy resin (A), Ar in general formula (2) representing structural unit X, and Ar in general formula (3) representing structural unit Y are all structures containing an aromatic ring that is either unsubstituted or has a substituent. Furthermore, there is no particular limitation on the aromatic ring; examples include: benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, and fluorene ring.

[0101] Of these, Ar is preferably any structure represented by the following structural formula (ar).

[0102] [Chemistry 8]

[0103]

[0104] [The aromatic ring in formula (ar) may be substituted or unsubstituted; * indicates a bond site.]

[0105] Alternatively, the structure represented by the following formula can also be cited as Ar.

[0106] [Chemistry 9]

[0107]

[0108] (In the formula, the aromatic ring can be substituted or unsubstituted, n3=1~4, and * indicates the bonding site).

[0109] The aromatic ring of Ar can be substituted or unsubstituted. When Ar has substituents, preferred substituents include alkyl groups, halogen atoms, glycidyl ether groups, and 2-methylglycidyl ether groups. Unsubstituted substituents are preferred, as are alkyl groups, glycidyl ether groups, and 2-methylglycidyl ether groups. For each aromatic ring, substituents are preferably two or fewer, more preferably one or fewer, and particularly preferably unsubstituted.

[0110] As for the aforementioned Ar structure, the following structure is particularly preferred. * indicates a bonding point.

[0111] [Chemistry 10]

[0112]

[0113] The following structures are particularly preferred structures for Ar with substituents. * indicates a bond site.

[0114] [Chemistry 11]

[0115]

[0116] R is a hydrogen atom or a methyl group.

[0117] In the structural unit X represented by the aforementioned general formula (2), the repeating unit n1 is an integer from 4 to 16. When n1 is 4 or more, in addition to the increase in adhesive strength, the deformation mode of the cured material becomes elastic deformation. Furthermore, when n1 is 16 or less, the decrease in crosslinking density can be suppressed. Preferably, it is 4 to 15, and more preferably 6 to 12.

[0118] In the structural unit X represented by the aforementioned general formula (2), R 1 R 2 Each is independently a hydrogen atom, methyl or ethyl, R 3 R 4 Each is independently a hydroxyl, glycidyl ether, or 2-methylglycidyl ether group, R 5 R 6 Each can be a hydrogen atom or a methyl group independently.

[0119] Among these, as R 3 R 4 Preferably, hydroxyl group, R 5 R 6 Hydrogen atoms are preferred.

[0120] In the structural unit Y represented by the aforementioned general formula (3), n2 is the average value of the repeating units and is 2 to 30. If this range is met, the balance between the viscosity of the epoxy resin (A) and the crosslinking density of the resulting cured product becomes good, which is preferable. Preferably, it is 2 to 25, and more preferably 4 to 20.

[0121] In the structural unit Y represented by the aforementioned general formula (3), R' is a divalent hydrocarbon group with 2 to 12 carbon atoms. If this range is met, in addition to increased adhesive strength, the deformation mode of the cured material will become elastic deformation. Preferably, R' is a divalent hydrocarbon group with 2 to 6 carbon atoms.

[0122] As the aforementioned divalent hydrocarbon group, there are no particular limitations, and examples include: straight-chain or branched alkylene, alkenylene, ynylene, cycloalkylene, arylene, and arylalkylene (divalent groups having alkylene and arylene), etc.

[0123] Examples of alkylene groups include: methylene, ethylene, propyleneene, butylene, pentylene, hexylene, trimethylene, tetramethylene, pentamethylene, hexamethylene, etc. Examples of alkenylene groups include: vinylene, 1-methylvinylene, propenylene, butenylene, pentenylene, etc. Examples of ynynylene groups include: ethynylene, propynylene, butynylene, pentylene, hexynylene, etc. Examples of cycloalkylene groups include: cyclopropylene, cyclobutylene, cyclopentylene, cyclohexylene, etc. Examples of arylene groups include: phenylene, tolylene, xylene, naphthylene, etc.

[0124] Among these, from the viewpoint of balancing the ease of obtaining raw materials, the viscosity of the resulting epoxy resin (A), and the flexibility when made into a cured product, ethylene, propylene, and tetramethylene are preferred.

[0125] In the structural unit Y represented by the aforementioned general formula (3), R 7 R 8 Each is independently a hydroxyl, glycidyl ether, or 2-methylglycidyl ether group, R 9 R 10 Each can be independently a hydrogen atom or a methyl group. As R 7 R 8 Preferably, hydroxyl group is used as R. 9 R 10 Preferably, it contains hydrogen atoms.

[0126] As described above, the epoxy resin (A) used in this embodiment is the epoxy resin represented by the aforementioned general formula (1). In the aforementioned general formula (1), m1 and m2 are the repeated average values ​​of the aforementioned structural unit X and structural unit Y, respectively, each independently ranging from 0 to 25, and m1 + m2 ≥ 1.

[0127] In addition, R in the aforementioned general formula (1) 11 R 12 Each is independently a glycidyl ether group or a 2-methylglycidyl ether group, R 13 R 14 Each is independently a hydroxyl, glycidyl ether, or 2-methylglycidyl ether group, R 15 R 16 For hydrogen atoms or methyl groups, p1, p2, and q are repeated averages, where p1 and p2 are independently 0–5, and q is 0.5–5. Among these, R 11 R 12 Preferably, it is a glycidyl ether group, R 13 R14 Preferably, hydroxyl group, R 15 R 16 Hydrogen atoms are preferred. Furthermore, p1 and p2 are preferably 0 to 2, and q is preferably 0.5 to 2.

[0128] Furthermore, the epoxy equivalent of the epoxy resin (A) used in this embodiment is 500 to 10,000 g / eq. Within this range, it becomes an epoxy resin with an excellent balance between the flexibility and crosslinking density of the resulting cured product. From the viewpoint of ease of handling and a more balanced flexibility / crosslinking density, a range of 600 to 8,000 g / eq is preferred, and a range of 800 to 5,000 g / eq is more preferred.

[0129] In the epoxy resin (A) of this embodiment, a resin having both the aforementioned structural unit X and structural unit Y in one molecule can be exemplified by the following structural formula.

[0130] [Chemistry 12]

[0131]

[0132] [Chemistry 13]

[0133]

[0134] [Chemistry 14]

[0135]

[0136] [Chemistry 15]

[0137]

[0138] [Chemistry 16]

[0139]

[0140] [Chemistry 17]

[0141]

[0142] [Chemistry 18]

[0143]

[0144] [Chemistry 19]

[0145]

[0146] [Chemistry 20]

[0147]

[0148] [Chemistry 21]

[0149]

[0150] [Chemistry 22]

[0151]

[0152] [Chemistry 23]

[0153]

[0154] In the above structural formulas (A-1) to (A-12), ran represents random bonding, G is glycidyl group, R' represents a divalent hydrocarbon group with 2 to 12 carbon atoms, n1 is an integer from 4 to 16, n2 is the average value of the repeating unit and is 2 to 30, m1, m2, p1, p2, and q are the average values ​​of the repeating units, m1 and m2 are each independently 0.5 to 25, p1 and p2 are each independently 0 to 5, and q is 0.5 to 5. The repeating units within the repeating units can be the same or different.

[0155] Among the above structural formulas, from the viewpoint that the resulting cured product has a better balance of physical properties, the epoxy resin represented by the aforementioned structural formulas (A-1), (A-2), (A-3), (A-5), (A-7), (A-8), and (A-9) is the most preferred.

[0156] Among the aforementioned epoxy resins (A), the epoxy resin having structural unit X can be exemplified by the resin represented by the following structural formula.

[0157] [Chemistry 24]

[0158]

[0159] [Chemistry 25]

[0160]

[0161] [Chemistry 26]

[0162]

[0163] [Chemistry 27]

[0164]

[0165] [Chemistry 28]

[0166]

[0167] [Chemistry 29]

[0168]

[0169] [Chemistry 30]

[0170]

[0171] [Chemistry 31]

[0172]

[0173] [Chemistry 32]

[0174]

[0175] [Chemistry 33]

[0176]

[0177] [Chemistry 34]

[0178]

[0179] [Chemistry 35]

[0180]

[0181] In the above structural formulas (A-13) to (A-24), G is a glycidyl group, n1 is an integer from 4 to 16, m1, p1, p2, and q are the average values ​​of the repeats, m1 is 0.5 to 25, p1 and p2 are each independently 0 to 5, and q is 0.5 to 5. The repeating units within the repeating units can be the same or different.

[0182] Among the above structural formulas, the epoxy resins represented by the aforementioned structural formulas (A-13), (A-14), (A-15), (A-17), (A-19), (A-20), and (A-21) are preferred from the perspective of having a better balance of physical properties of the resulting cured product.

[0183] Among the aforementioned epoxy resins (A), the epoxy resin having structural unit Y can be exemplified by the resin represented by the following structural formula.

[0184] [Chemistry 36]

[0185]

[0186] [Chemistry 37]

[0187]

[0188] [Chemistry 38]

[0189]

[0190] [Chemistry 39]

[0191]

[0192] [Chemistry 40]

[0193]

[0194] [Chemistry 41]

[0195]

[0196] [Chemistry 42]

[0197]

[0198] [Chemistry 43]

[0199]

[0200] [Chemistry 44]

[0201]

[0202] [Chemistry 45]

[0203]

[0204] [Chemistry 46]

[0205]

[0206] [Chemistry 47]

[0207]

[0208] In the above structural formulas (A-25) to (A-36), G is a glycidyl group, R' is a divalent hydrocarbon group with 2 to 12 carbon atoms, n2 is the average value of the repeating unit and is 2 to 30, m2, p1, p2, and q are the average values ​​of the repeating units, m2 is 0.5 to 25, p1 and p2 are each independently 0 to 5, and q is 0.5 to 5. The repeating units within the repeating units can be the same or different.

[0209] Among the above structural formulas, the epoxy resins represented by the aforementioned structural formulas (A-25), (A-26), (A-27), (A-29), (A-31), (A-32), and (A-33) are most preferred in terms of the superior physical property balance of the resulting cured product.

[0210] <Method for manufacturing epoxy resin (A)>

[0211] The method for manufacturing the epoxy resin (A) described in this embodiment is not particularly limited. For example, from the perspective of obtaining raw materials and facilitating the reaction, the following method is preferred: diglycidyl ether (a1) of a dihydroxy compound having an alkylene chain or a polyether chain is reacted with an aromatic hydroxy compound (a2) in a molar ratio (a1) / (a2) of 1 / 1.01 to 1 / 5.0 to obtain a hydroxy compound [equivalent to a precursor or intermediate of epoxy resin (A)], and then reacted with epihalool (a3).

[0212] Although the product obtained from the aforementioned reaction in which diglycidyl ether (a1) of a dihydroxy compound having an alkylene chain or a polyether chain reacts with an aromatic hydroxy compound (a2) to obtain a hydroxy compound contains unreacted aromatic hydroxy compound (a2), it can be directly supplied to the next step, namely the reaction with epihaloalcohol (a3), when synthesizing the epoxy resin (A) used in this embodiment. Alternatively, the unreacted aromatic hydroxy compound (a2) can be removed. However, from the viewpoint of balancing the toughness and flexibility of the cured product obtained from the epoxy resin composition of this embodiment containing the obtained epoxy resin (A), the presence rate of the aforementioned unreacted aromatic hydroxy compound (a2) in the hydroxy compound supplied to the next step is preferably in the range of 0.1% to 30% by mass.

[0213] The method for removing the unreacted aromatic hydroxyl compound (a2) is not particularly limited and can be carried out by various methods. Examples include column chromatography using polarity differences, distillation using boiling point differences, and alkaline aqueous solution extraction using differences in solubility in alkaline water. Among these, alkaline aqueous solution extraction is preferred from the perspective of efficiency, as it does not involve thermal degradation. In this case, organic solvents that do not mix with water, such as toluene or methyl isobutyl ketone, can be used as the organic solvent to dissolve the target compound. Furthermore, from the viewpoint of solubility in the target compound, methyl isobutyl ketone is particularly preferred.

[0214] The diglycidyl ether (a1) that is a dihydroxy compound having an alkylene chain or a polyether chain is not particularly limited. Examples of diglycidyl ethers having an alkylene chain include: 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,9-nonanediol diglycidyl ether, 1,11-undecanediol diglycidyl ether, 1,12-dodecanediol diglycidyl ether, 1,13-tridecanediol diglycidyl ether, 1,14-tetradecanediol diglycidyl ether, 1,15-pentadecanediol diglycidyl ether, 1,16-hexadecanediol diglycidyl ether, 2-methyl-1,11-undecanediol diglycidyl ether, 3-methyl-1,11-undecanediol diglycidyl ether, and 2,6,10-trimethyl-1,11-undecanediol diglycidyl ether. In addition, examples of diglycidyl ethers having polyether chains include: polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polytetramethylene glycol diglycidyl ether, polypentamethylene glycol diglycidyl ether, polyhexamethylene glycol diglycidyl ether, and polyheptamethylene glycol diglycidyl ether. These may contain organochlorine impurities generated during the glycidyl etherification of hydroxyl compounds, or may contain organochlorine compounds such as 1-chloromethyl-2-glycidyl ether (chloromethyl group) as shown in the following structure. These diglycidyl ethers can be used alone or in combination of two or more.

[0215] [Chemistry 48]

[0216]

[0217] Among these, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, 1,9-nonanediol diglycidyl ether, 1,12-dodecanediol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and polytetramethylene glycol diglycidyl ether are preferred in terms of the excellent balance between the resulting cured product's softness and heat resistance.

[0218] In addition, by reacting the aforementioned diglycidyl ether with an alkylene chain and the diglycidyl ether with a polyether chain simultaneously with an aromatic hydroxyl compound (a2), a hydroxyl compound having both structural unit X and structural unit Y can be obtained. By further reacting it with epihalool (a3), an epoxy resin (A) having both structural unit X and structural unit Y can be obtained.

[0219] The aforementioned aromatic hydroxyl compound (a2) is not particularly limited, and examples include: dihydroxybenzenes such as hydroquinone, resorcinol, and catechol; pyrogallol; trihydroxybenzenes such as 1,2,4-trihydroxybenzene and 1,3,5-trihydroxybenzene; triphenylmethane-type phenols such as 4,4',4"-trihydroxytriphenylmethane; dihydroxynaphthalenes such as 1,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, and 2,6-dihydroxynaphthalene; and 1,1'-methylenebis(2,7-naphthalenediol) obtained by coupling dihydroxynaphthalenes. Bis(2,2',7,7'-tetraol), 1,1'-oxybis(2,7-naphthyldiol) and other tetrafunctional phenols, bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane and 1,1-bis(4-hydroxyphenyl)-1-phenylethane and bis(4-hydroxyphenyl)sulfone and other bisphenols, 2,2'-biphenol, 4,4'-biphenol, (1,1'-biphenyl)-3,4-diol, 3,3'-dimethyl-(1,1'-biphenyl)-4,4'-diol, 3-methyl-( 1,1'-biphenyl)-4,4'-diol, 3,3',5,5'-tetramethylbiphenyl-2,2'-diol, 3,3',5,5'-tetramethylbiphenyl-4,4'-diol, 5-methyl-(1,1'-biphenyl)-3,4'-diol, 3'-methyl-(1,1'-biphenyl)-3,4'-diol, 4'-methyl-(1,1'-biphenyl)-3,4'-diol and other biphenyl phenols, addition polymers of phenols with dicyclopentadiene and addition polymers of phenols with terpenoids and other phenols containing alicyclic structures, naphthols such as bis(2-hydroxy-1-naphthyl)methane and bis(2-hydroxy-1-naphthyl)propane, phenols with The condensation reaction products of phenylene dimethyl chloride or biphenylene dimethyl chloride, namely the so-called Xylok-type phenolic resin, can be used alone or in combination with two or more. Furthermore, compounds with structures in which methyl, tert-butyl, or halogen atoms as substituents are substituted on the aromatic nucleus of the aforementioned compounds can also be cited. It should be noted that the aforementioned phenols containing alicyclic structures and the aforementioned Xylok-type phenolic resins can not only simultaneously contain two functional components, but also simultaneously contain three or more functional components. In this invention, they can be used directly, or they can be used after purification processes such as column chromatography to extract only the two functional components.

[0220] Among these, bisphenols are preferred in terms of their excellent balance between softness and toughness when cured, and bis(4-hydroxyphenyl)methane and 2,2-bis(4-hydroxyphenyl)propane are preferred, especially in terms of their significant ability to impart toughness. Furthermore, when the curing properties and heat resistance of the cured product are important, dihydroxynaphthalenes are preferred, especially 2,7-dihydroxynaphthalene, which significantly imparts rapid curing properties. Additionally, when the moisture resistance of the cured product is important, compounds containing alicyclic structures are preferred.

[0221] Regarding the reaction ratio of the diglycidyl ether (a1) of the aforementioned dihydroxy compound having alkylene chain and polyether chain to the aforementioned aromatic hydroxy compound (a2), from the viewpoint of reaction efficiency, it is preferable that (a1) / (a2) is 1 / 1.01 to 1 / 5.0 (molar ratio), and more preferably that (a1) / (a2) is 1 / 1.02 to 1 / 3.0 (molar ratio).

[0222] The reaction of the diglycidyl ether (a1) of the aforementioned dihydroxy compound having alkylene chain and polyether chain with the aforementioned aromatic hydroxy compound (a2) is preferably carried out in the presence of a catalyst. Various catalysts can be used as the aforementioned catalysts, such as: alkali (earth) metal hydroxides such as sodium hydroxide, potassium hydroxide, lithium hydroxide, and calcium hydroxide; alkali metal carbonates such as sodium carbonate and potassium carbonate; phosphorus compounds such as triphenylphosphine; chlorides, bromides, and iodides of tetramethylammonium, tetraethylammonium, tetrabutylammonium, and benzyltributylammonium; quaternary ammonium salts such as chlorides, bromides, and iodides of tetramethylphosphonium, tetraethylphosphonium, tetrabutylphosphonium, and benzyltributylphosphonium; triethylamine; N,N-dimethylbenzylamine; tertiary amines such as 1,8-diazabicyclo[5.4.0]undecene and 1,4-diazabicyclo[2.2.2]octane; and imidazoles such as 2-ethyl-4-methylimidazolium and 2-phenylimidazolium. Two or more catalysts can also be used in combination. From the viewpoint of rapid reaction and high impurity reduction, sodium hydroxide, potassium hydroxide, triphenylphosphine, and DMP-30 are preferred. The amount of these catalysts used is not particularly limited, but 0.0001 to 0.1 moles are preferred relative to 1 mole of the phenolic hydroxyl group in the aforementioned aromatic hydroxyl compound (a2). The form of these catalysts is also not particularly limited; they can be used in aqueous solution or solid form.

[0223] Furthermore, the reaction between the aforementioned diglycidyl ether (a1) of the dihydroxy compound having alkylene chains and polyether chains and the aforementioned aromatic hydroxy compound (a2) can be carried out in the absence of a solvent or in the presence of an organic solvent. Examples of usable organic solvents include: methyl cellosolve, ethyl cellosolve, toluene, xylene, methyl isobutyl ketone, dimethyl sulfoxide, propanol, butanol, etc. The amount of organic solvent used is typically 50-300% by mass relative to the total mass of the raw materials input, preferably 100-250% by mass. These organic solvents can be used alone or in combination. For rapid reaction, a solvent-free reaction is preferred; on the other hand, from the viewpoint of reducing impurities in the final product, dimethyl sulfoxide is preferred.

[0224] The reaction temperature for carrying out the aforementioned reaction is typically 50–180°C, and the reaction time is typically 1–30 hours. From the viewpoint of reducing impurities in the final product, the reaction temperature is preferably 100–160°C. Furthermore, if the obtained compound exhibits significant coloration, antioxidants or reducing agents can be added to suppress this. Antioxidants are not particularly limited, and examples include hindered phenolic compounds such as 2,6-dialkylphenol derivatives, divalent sulfur compounds, and phosphite compounds containing trivalent phosphorus atoms. Reducing agents are not particularly limited, and examples include hypophosphorous acid, phosphorous acid, thiosulfate, sulfurous acid, bisulfite, or their salts.

[0225] After the aforementioned reaction is complete, neutralization or washing can be performed until the pH of the reaction mixture reaches 3-7, preferably 5-7. Neutralization and washing can be carried out using conventional methods. For example, when using an alkaline catalyst, acidic substances such as hydrochloric acid, sodium dihydrogen phosphate, p-toluenesulfonic acid, or oxalic acid can be used as neutralizing agents. After neutralization or washing, if necessary, the solvent can be removed by distillation under reduced pressure and heating to concentrate the product and obtain the hydroxyl compound.

[0226] By combining the aforementioned glycidyl ether having an alkylene chain and a glycidyl ether having a polyether chain, a hydroxyl compound having both the aforementioned structural unit X and the aforementioned structural unit Y can be obtained. As a preferred structure at this time, compounds represented by the following structural formulas can be cited as examples.

[0227] [Chemistry 49]

[0228]

[0229] [Transformation 50]

[0230]

[0231] [Chemistry 51]

[0232]

[0233] [Chemistry 52]

[0234]

[0235] [Chemistry 53]

[0236]

[0237] [Chemistry 54]

[0238]

[0239] [Chemistry 55]

[0240]

[0241] [Chemistry 56]

[0242]

[0243] [Chemistry 57]

[0244]

[0245] [Chem.58]

[0246]

[0247] [Chemistry 59]

[0248]

[0249] [Transformation 60]

[0250]

[0251] In the above structural formulas, ran represents random bonding, R' is a divalent hydrocarbon group with 2 to 12 carbon atoms, n1 is an integer from 4 to 16, n2 is the average value of the repeating unit and is 2 to 30, and m1 and m2 are the average values ​​of the repeating units, each independently ranging from 0.5 to 25. The repeating units within each repeating unit can be the same or different.

[0252] Furthermore, by using the aforementioned glycidyl ether having an alkylene chain as a raw material, a hydroxyl compound having the aforementioned structural unit X can be obtained. As a preferred structure at this time, compounds represented by the following structural formulas can be cited as examples.

[0253] [Chemistry 61]

[0254]

[0255] [Chemistry 62]

[0256]

[0257] [Chemistry 63]

[0258]

[0259] [Chemistry 64]

[0260]

[0261] [Chemistry 65]

[0262]

[0263] [Chemistry 66]

[0264]

[0265] [Chemistry 67]

[0266]

[0267] [Chemistry 68]

[0268]

[0269] [Chemistry 69]

[0270]

[0271] [Chemistry 70]

[0272]

[0273] [Chemistry 71]

[0274]

[0275] [Chemistry 72]

[0276]

[0277] In the above structural formulas, n1 is an integer from 4 to 16, and m1 is the average value of the repeated values, which is from 0.5 to 25.

[0278] In addition, by using the aforementioned glycidyl ether having a polyether chain as a raw material, a hydroxyl compound having the aforementioned structural unit Y can be obtained. As a preferred structure at this time, for example, a compound represented by the following structural formula can be cited.

[0279] [Chemistry 73]

[0280]

[0281] [Chemistry 74]

[0282]

[0283] [Chemistry 75]

[0284]

[0285] [Chemistry 76]

[0286]

[0287] [Chemistry 77]

[0288]

[0289] [Chemistry 78]

[0290]

[0291] [Chemistry 79]

[0292]

[0293] [Chemistry 80]

[0294]

[0295] [Chemistry 81]

[0296]

[0297] [Chemistry 82]

[0298]

[0299] [Chemistry 83]

[0300]

[0301] [Chemistry 84]

[0302]

[0303] In the above structural formulas, R' is a divalent hydrocarbon group with 2 to 12 carbon atoms, n2 is the average value of the repeating unit and ranges from 2 to 30, and m2 is the average value of the repeating unit and ranges from 0.5 to 25. The repeating units within the repeating unit may be the same or different.

[0304] In the aforementioned method for manufacturing epoxy resin (A), the method for the glycidyl etherification reaction of the obtained precursor (intermediate) hydroxyl compound is not particularly limited, and examples include: reacting phenolic hydroxyl groups with epihaloalcohols, olefinizing phenolic hydroxyl groups, and oxidizing the carbon-carbon double bond of the olefin with an oxidizing agent. Among these, the method using epihaloalcohols (a3) ​​is preferred from the perspective of obtaining raw materials and ease of reaction.

[0305] One method for using epihalool (a3) ​​is as follows: For 1 mole of the aromatic hydroxyl group of the aforementioned hydroxyl compound, 0.3 to 100 moles of epihalool (a3) ​​are added, and for this mixture, a basic catalyst of 0.9 to 2.0 moles relative to 1 mole of the aromatic hydroxyl group of the hydroxyl compound is added either all at once or slowly, while the mixture is reacted at a temperature of 20 to 120°C for 0.5 to 10 hours. Regarding the amount of epihalool (a3) ​​added, the greater the excess of epihalool (a3), the closer the resulting epoxy resin is to its theoretical structure, and the formation of secondary hydroxyl groups generated from the reaction of unreacted aromatic hydroxyl groups with epoxy groups can be suppressed. From this viewpoint, a range of 2.5 to 100 equivalents is preferred. This alkaline catalyst can be used in the solid state or in its aqueous solution. When using the aqueous solution, it allows for the continuous distillation of water and epihalool (a3) ​​from the reaction mixture under reduced pressure or normal pressure while being continuously added, followed by separation to remove water and continuously return the epihalool (a3) ​​to the reaction mixture.

[0306] It should be noted that in industrial production, in the first batch of epoxy resin production, all epihaloalcohols (a3) ​​used are virgin epihaloalcohols. However, in subsequent batches, it is preferable to use epihaloalcohols (a3) ​​recovered from the crude reaction product in combination with virgin epihaloalcohols (a3) ​​in amounts equivalent to those consumed and lost in the reaction. The epihaloalcohol (a3) ​​used in this process is not particularly limited; examples include epichlorohydrin and epibromohydrin. Epichlorohydrin is preferred due to its easy availability.

[0307] Furthermore, there are no particular limitations on alkaline catalysts, and examples include alkaline earth metal hydroxides, alkali metal carbonates, and alkali metal hydroxides. Especially from the perspective of excellent catalytic activity in epoxy resin synthesis reactions, alkali metal hydroxides are preferred, such as sodium hydroxide and potassium hydroxide. These alkali metal hydroxides can be used in the form of an aqueous solution of approximately 10-55% by mass, or in a solid state.

[0308] Furthermore, the reaction rate in the synthesis of epoxy resins can be increased by using organic solvents in combination. There are no particular limitations on such organic solvents; examples include: ketones such as acetone and methyl ethyl ketone; alcohols such as methanol, ethanol, 1-propanol, isopropanol, 1-butanol, sec-butanol, and tert-butanol; cellosolves such as methyl cellosolves and ethyl cellosolves; ethers such as tetrahydrofuran, 1,4-dioxane, 1,3-dioxane, and diethoxyethane; and aprotic polar solvents such as acetonitrile, dimethyl sulfoxide, and dimethylformamide. These organic solvents can be used individually, or two or more can be used in combination to adjust polarity.

[0309] After washing the reaction products of these glycidylation reactions with water, the unreacted epihaloalcohols (a3) ​​and the organic solvents used are removed by distillation under heating and reduced pressure. Furthermore, to further prepare epoxy resins with low hydrolytic halogen content, the resulting epoxy resin can be dissolved again in organic solvents such as toluene, methyl isobutyl ketone, and methyl ethyl ketone, and an aqueous solution of alkali metal hydroxides such as sodium hydroxide and potassium hydroxide can be added for further reaction. In this case, phase transfer catalysts such as quaternary ammonium salts and crown ethers can be present to increase the reaction rate.

[0310] When using a phase transfer catalyst, the amount used is preferably in the range of 0.1 to 3.0% by mass relative to the epoxy resin used. After the reaction is complete, the generated salt is removed by filtration, washing with water, etc., and then solvents such as toluene and methyl isobutyl ketone are distilled off under heating and reduced pressure, thereby obtaining a high-purity epoxy resin.

[0311] [Epoxy Resin (B)]

[0312] The epoxy resin (B) contained in the epoxy resin of this embodiment is only required to have an epoxy equivalent in the range of 100 to 300 g / eq, and its structure is not limited. Examples include: liquid epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD ​​type epoxy resin, polyhydroxybenzene type epoxy resin, polyhydroxynaphthalene type epoxy resin, biphenyl type epoxy resin, tetramethylbiphenyl type epoxy resin, brominated epoxy resins such as brominated phenolic varnish type epoxy resin, solid bisphenol A type epoxy resin, phenolic varnish type epoxy resin, cresolic phenolic varnish type epoxy resin, triphenylmethane type epoxy resin, tetraphenylethane type epoxy resin, and dicyclopentadiene-phenolic resin. Reactive epoxy resins, phenolic aralkyl epoxy resins, phenylene ether epoxy resins, naphthylene ether epoxy resins, naphthol phenolic varnish epoxy resins, naphthol aralkyl epoxy resins, naphthol-phenol cocondensed phenolic varnish epoxy resins, naphthol-cresol cocondensed phenolic varnish epoxy resins, aromatic hydrocarbon formaldehyde resin modified phenolic resin epoxy resins, biphenyl modified phenolic varnish epoxy resins, etc., can be used alone or in combination of two or more types. It is preferable to select the appropriate type based on the target application, the physical properties of the cured product, etc.

[0313] Among these, epoxy resins with an epoxy equivalent of 100-300 g / eq are preferred, including bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD ​​type epoxy resin, polyhydroxybenzene type epoxy resin, polyhydroxynaphthalene type epoxy resin, biphenyl type epoxy resin, and tetramethylbiphenyl type epoxy resin. Epoxy resins with an epoxy equivalent of 100-300 g / eq are particularly preferred, especially those with an epoxy equivalent of 100-300 g / eq, such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, and bisphenol AD ​​type epoxy resin.

[0314] In this embodiment, the ratio of epoxy resin (A) to epoxy resin (B) is not particularly limited. From the viewpoint of facilitating phase separation in the cured product, the mass ratio (A):(B) of epoxy resin (A) is 90:10 to 10:90, preferably 80:20 to 20:80, and particularly preferably 70:30 to 30:70. By achieving a sea-island structure through phase separation in the cured product, both the adhesiveness and stress-relieving ability of the cured product can be achieved. In particular, it can exhibit high adhesive strength over a wide temperature range and has the effect of reducing the molding shrinkage rate of the resin composition before and after heat curing.

[0315] [Compounds containing glycidyl ether groups (C)]

[0316] The epoxy resin composition of this embodiment contains a compound (C) containing a glycidyl ether group, which is represented by the following general formula (4).

[0317] [Chemistry 85]

[0318]

[0319] In equation (4), m3 is an integer from 1 to 4. 1 For any of the structures represented by the following equation (5), Z 3 For any of the structures represented by the following formula (6), a molecule may have multiple structures, which may be the same or different.

[0320] [Chemistry 86]

[0321]

[0322] [The aromatic ring in formula (5) can be substituted or unsubstituted, and * indicates a bonding site. G is glycidyl or 2-methylglycidyl, and -OG on the naphthalene ring in the formula indicates that it can be bonded at any location.]

[0323] [Chemistry 87]

[0324]

[0325] (In formula (6), R' is a divalent hydrocarbon group with 2 to 12 carbon atoms, R” is independently a hydrogen atom, methyl or ethyl, n1 is an integer from 1 to 30, n2 is the average of the number of repetitions and is 0.5 to 8, and * indicates a bonding point.)

[0326] The compound containing glycidyl ether group in this embodiment is characterized in that it is formed by reversible bonding via a Diels-Alder reaction based on the maleimide structure and the furan structure.

[0327] With this configuration, compounds containing glycidyl ether groups are introduced into the cross-linked structure via a curing reaction based on these groups. Furthermore, due to the reversibility after curing, high molecular mobility is maintained even within the cured product. Consequently, when the cured product is exposed to high temperatures or subjected to impacts that cause cracking or shattering, the aforementioned reversible bonds are easily broken, exhibiting easy disintegration. Moreover, these reversible bonds can reversibly reform in low-temperature regions, including room temperature, resulting in excellent adhesion.

[0328] To introduce a furan-type addition structure (reversible bond) based on the aforementioned Diels-Alder reaction into a compound, from the perspective of ease of preparation, it is preferable to use a method using furan with reactive functional groups on the ring and maleimide with reactive functional groups. The specific reversible bond structure can be represented by the following chemical formula. A reversible bond can be introduced into the compound by bonding it to other structural units based on the R portion of the structure derived from maleimide and various reactive functional groups on the ring derived from furan.

[0329] [Chemistry 88]

[0330]

[0331] In the Diels-Alder reaction, a conjugated diene undergoes an addition reaction with a dienophile to form a 6-membered ring. The Diels-Alder reaction is an equilibrium reaction; therefore, at a predetermined temperature, a reverse Diels-Alder reaction occurs, resulting in dissociation (decrosslinking). When mechanical energy such as damage or external force is applied to the resulting cured product, the C-C bonds of the Diels-Alder reaction unit are preferentially cleaved because their bonding energy is lower than that of ordinary covalent bonds. Therefore, the cured product exhibits easy dissociation. Furthermore, in temperature regions below the dissociation temperature, the equilibrium of the C-C bonds in the Diels-Alder reaction unit shifts towards bonding, thus forming an adduct (Diels-Alder reaction unit) again.

[0332] Among reversible bonds based on the Diels-Alder reaction, for example, the Diels-Alder reaction units formed by anthracene and maleimide structures have dissociation temperatures as high as 250°C or higher, and do not dissociate at least around 200°C. On the other hand, reversible bonds based on the furan and maleimide structures undergo a reverse Diels-Alder reaction and dissociate (de-crosslinking) around 120°C. Therefore, the heating temperature required for the cured product to exhibit easy dissociation can be reduced, resulting in excellent easy dissociation for applications where high-temperature heating is not suitable.

[0333] The average molecular weight (Mw) of the aforementioned compound (C) containing glycidyl ether groups is less than 1000 from the viewpoint that it combines mechanical strength, flexibility and easy disassembly when made into a cured product.

[0334] In the aforementioned general formula (4), the terminal has a reversible bond formed by furan and maleimide. In the furan structure at the terminal of general formula (4), there is a Z-shaped structure represented by any of the aforementioned general formula (5). 1 The glycidyl ether group or 2-methylglycidyl ether group contributes to the curing reaction in the epoxy resin composition described later.

[0335] Z in the formula 1 The structural unit represented by the aforementioned general formula (5) has a glycidyl ether group or a 2-methylglycidyl ether group. Furthermore, from the viewpoint of ease of obtaining raw materials and reactivity, the structural unit of the following formula is preferred: G is a glycidyl group or a 2-methylglycidyl group.

[0336] [Chemistry 89]

[0337]

[0338] In the aforementioned general formula (6), R' is a divalent hydrocarbon group with 2 to 12 carbon atoms, R” is independently a hydrogen atom, methyl or ethyl, n1 is an integer from 1 to 30, and n2 is the average of the number of repetitions and is 0.5 to 8. Among these, from the viewpoint of ease of obtaining raw materials and the mechanical properties of the obtained solidified product, it is preferable that n1 is in the range of 1 to 15, n2 is in the range of 0.5 to 3, n3 is preferably an integer from 1 to 4, and R” is preferably a hydrogen atom.

[0339] Examples of compounds (C) containing glycidyl ether groups in this embodiment include, but are not limited to, the compounds shown below.

[0340] [Chemistry 90]

[0341]

[0342] The method for manufacturing the compound (C) containing a glycidyl ether group in this embodiment is not particularly limited. It can be manufactured stepwise using a known reaction according to the target structure. Alternatively, it can be obtained by appropriately combining commercially available products as raw materials. Representative synthetic methods are described below.

[0343] Regarding the compound represented by the aforementioned general formula (4), it has two reversible addition reaction units formed by the Diels-Alder reaction, which contain furan and maleimide structures, within the molecule, and can be obtained by using Z in general formula (4). 1 It is obtained by obtaining furan compounds with the structure of [missing information].

[0344] The so-called Diels-Alder reaction, in which conjugated dienes such as furan structures undergo addition reactions with diephiles such as maleimide structures to form a 6-membered ring, is an equilibrium reaction. At temperatures higher than those during the addition reaction, the addition reaction will dissociate and return to the original conjugated diene and diephile reaction, i.e., the reverse Diels-Alder reaction. These are well known.

[0345] As having the aforementioned Z 1The precursors of the furan compounds with the structure are furan compounds having hydroxyl groups, and examples include any of the compounds listed in the following formulas. The hydroxyl groups in the compounds can be formed into glycidyl ether groups, for example, by the known methods described in the examples.

[0346] [Chemistry 91]

[0347]

[0348] Among the above formulas, the compounds shown below in particular are especially preferred because they exhibit excellent reactivity and properties of the cured product, as well as the adhesiveness, flexibility, and disassembly of the resulting cured product.

[0349] [Chemistry 92]

[0350]

[0351] It should be noted that the structures of the aforementioned furan compounds each independently include structures having hydrogen atoms, halogen atoms, alkoxy groups, arylalkoxy groups, aryloxy groups, nitro groups, amide groups, alkoxycarbonyl groups, aryloxycarbonyl groups, cyano groups, alkyl groups, cycloalkyl groups, aralkyl groups, or aryl groups as substituents. Furthermore, in the structures of the compounds listed above, alkoxy groups, arylalkoxy groups, aryloxy groups, carboxyl groups, alkoxycarbonyl groups, aryloxycarbonyl groups, alkyl groups, cycloalkyl groups, aralkyl groups, and aryl groups also include groups with various substituents further bonded to their carbon atoms.

[0352] The Diels-Alder reaction can be performed using any known method. For example, a conjugated diene compound and a diephile compound can be mixed in equimolar amounts, with one component in excess as needed. The mixture can then be heated to melt or dissolved in a solvent, stirred at room temperature to 110°C for 1 to 24 hours, and obtained directly by filtration or solvent distillation without purification. Alternatively, it can be obtained by commonly used separation and purification methods such as recrystallization, reprecipitation, and chromatography. It should be noted that the phrase "equimolar amounts of the conjugated diene compound and the diephile compound" means that the conjugated diene structure of the conjugated diene compound and the ethylene structure of the diephile compound are in equimolar amounts. For example, in the case of the compound (C) containing a glycidyl ether group represented by the above general formula (4), the aforementioned furan compound, as a conjugated diene compound, has one conjugated diene structure in one molecule, and the aforementioned maleimide compound (bismaleimide), as a diephile compound, has two maleimide structures (ethylene structure) in one molecule. In this case, the above "equal molar amounts of the conjugated diene compound and the diephile compound" means that the aforementioned furan compound and the aforementioned maleimide compound (bismaleimide) have a molar ratio of 2:1.

[0353] Regarding the synthesis of sites other than reversible bonds, known methods can be used. For example, after reacting an aliphatic dihydroxy compound's diglycidyl ether or aliphatic divinyl ether with an aromatic hydroxy compound to obtain a compound with a terminal hydroxyl group, it is reacted with glycidoxyphenyl maleimide, thereby introducing a maleimide structure to the terminal. Then, as described above, it is subjected to a Diels-Alder reaction with a furan compound having a glycidyl ether group to obtain the compound represented by the aforementioned general formula (4).

[0354] Alternatively, after obtaining a compound with a hydroxyl group at the end, it is epoxidized to make the end a glycidyl ether group, and then reacted with hydroxyphenyl maleimide, thereby introducing a maleimide structure to the end. Then, as described above, it is reacted with a furan compound having a glycidyl ether group to perform a Diels-Alder reaction, thereby obtaining the compound represented by the aforementioned general formula (4).

[0355] Alternatively, an aromatic dihydroxy compound is reacted with a dihaloalkyl compound or a dihaloaralkyl compound to obtain a compound with a terminal haloalkyl group, and then reacted with hydroxyphenyl maleimide, thereby introducing a maleimide structure to the end. Then, as described above, a furan compound with a glycidyl ether group is subjected to a Diels-Alder reaction to obtain the compound represented by the aforementioned general formula (4).

[0356] The diglycidyl ethers used as the aforementioned aliphatic dihydroxy compounds are not particularly limited. Examples include 1,11-undecanediol diglycidyl ether, 1,12-dodecanediol diglycidyl ether, 1,13-tridecanediol diglycidyl ether, 1,14-tetradecanediol diglycidyl ether, 1,15-pentadecande ...

[0357] Among these, from the viewpoint of achieving an excellent balance between the softness and heat resistance of the resulting cured product, compounds with a structure in which glycidyl groups are attached to both ends of an alkylene chain having 12 to 14 carbon atoms via ether groups are preferred, and 1,12-dodecanediol diglycidyl ether, 1,13-tridecanediol, and 1,14-tetradecanediol diglycidyl ether are most preferred.

[0358] The aforementioned aliphatic divinyl ethers are not particularly limited. Examples include: polyethylene glycol divinyl ether, polypropylene glycol divinyl ether, polytetramethylene glycol divinyl ether, 1,3-butanediol divinyl ether, 1,4-butanediol divinyl ether, 1,6-hexanediol divinyl ether, 1,9-nonanediol divinyl ether, 1,10-decanediol divinyl ether, and other straight-chain alkylene divinyl ethers; branched-chain alkylene divinyl ethers such as neopentyl glycol divinyl ether; 1,4-cyclohexanediol divinyl ether, 1,4-cyclohexanediethanol divinyl ether, tricyclodecanediol divinyl ether, tricyclodecanediethanol divinyl ether, pentacyclopentadecanediethanol divinyl ether, pentacyclopentadecanediol divinyl ether, and other divinyl ethers containing cycloalkane structures; bisphenol A divinyl ether, bisphenol F divinyl ether, hydroquinone divinyl ether, etc. These can be used alone or in combination with two or more.

[0359] Among these, the best balance between the resulting cured product's softness and toughness is achieved with divinyl ethers that have a polyether structure or straight-chain alkylene chains with 4 to 10 carbon atoms. The most preferred materials are polyethylene glycol divinyl ether, polypropylene glycol divinyl ether, polytetramethylene glycol divinyl ether, 1,4-butanediol divinyl ether, 1,6-hexanediol divinyl ether, 1,9-nonanediol divinyl ether, and 1,10-decanediol divinyl ether.

[0360] The aforementioned aromatic hydroxyl compounds are not particularly limited, but examples include: dihydroxybenzenes such as hydroquinone, resorcinol, and catechol; pyrogallol; trihydroxybenzenes such as 1,2,4-trihydroxybenzene and 1,3,5-trihydroxybenzene; triphenylmethane-type phenols such as 4,4',4"-trihydroxytriphenylmethane; dihydroxynaphthalenes such as 1,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, and 2,6-dihydroxynaphthalene; and 1,1'-methylenebis(2,7-naphthalenediol) and 1,1'-dihydroxynaphthalene obtained by coupling dihydroxynaphthalenes. Naphthalene-2,2',7,7'-tetraol, 1,1'-oxybis(2,7-naphthyldiol) and other tetrafunctional phenols, bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane and 1,1-bis(4-hydroxyphenyl)-1-phenylethane and bis(4-hydroxyphenyl)sulfone and other bisphenols, 2,2'-biphenol, 4,4'-biphenol, (1,1'-biphenyl)-3,4-diol, 3,3'-dimethyl-(1,1'-biphenyl)-4,4'-diol, 3-methyl Biphenyls such as -(1,1'-biphenyl)-4,4'-diol, 3,3',5,5'-tetramethylbiphenyl-2,2'-diol, 3,3',5,5'-tetramethylbiphenyl-4,4'-diol, 5-methyl-(1,1'-biphenyl)-3,4'-diol, 3'-methyl-(1,1'-biphenyl)-3,4'-diol, and 4'-methyl-(1,1'-biphenyl)-3,4'-diol; addition polymers of phenols with dicyclopentadiene and addition polymers of phenols with terpene compounds; phenols containing alicyclic structures such as bis(2-hydroxy-1-naphthyl)methane and bis(2-hydroxy-1-naphthyl)propane; and naphthalenes such as bis(2-hydroxy-1-naphthyl)methane and bis(2-hydroxy-1-naphthyl)propane. Phenolic compounds, and the condensation reaction products of phenols with phenylene dimethyl chloride or biphenylene dimethyl chloride, are known as selenoform resins. These can be used alone or in combination with two or more types. Furthermore, examples include difunctional phenolic compounds with methyl, tert-butyl, or halogen atoms as substituents on the aromatic nuclei of the aforementioned compounds. It should be noted that the aforementioned phenols containing alicyclic structures and the aforementioned selenoform resins can not only simultaneously contain difunctional components but also simultaneously contain three or more functional components. They can be used directly, or, alternatively, purified through column chromatography or other purification processes to extract only the difunctional components for use.

[0361] Among these, bisphenols are preferred in terms of their excellent balance between softness and toughness when cured, and especially in terms of their significant ability to impart toughness, bis(4-hydroxyphenyl)methane and 2,2-bis(4-hydroxyphenyl)propane are preferred. Furthermore, when the moisture resistance of the cured product is important, phenols containing alicyclic structures are preferred.

[0362] Regarding the reaction ratio of the aforementioned aliphatic dihydroxy compound diglycidyl ether to the aforementioned aromatic hydroxy compound, it is preferable to react them in a range of 1 / 1.01 to 1 / 5.0 (molar ratio). From the viewpoint of achieving a good balance between the softness and heat resistance of the resulting cured product, (a1) / (a2) is preferably 1 / 1.02 to 1 / 3.0 (molar ratio).

[0363] The reaction of the aforementioned aliphatic dihydroxy compound diglycidyl ether with the aforementioned aromatic hydroxy compound is preferably carried out in the presence of a catalyst. Various catalysts can be used as the aforementioned catalyst, such as: alkali (earth) metal hydroxides such as sodium hydroxide, potassium hydroxide, lithium hydroxide, and calcium hydroxide; alkali metal carbonates such as sodium carbonate and potassium carbonate; phosphorus compounds such as triphenylphosphine; chlorides, bromides, and iodides of DMP-30, DMAP, tetramethylammonium, tetraethylammonium, tetrabutylammonium, and benzyltributylammonium; quaternary ammonium salts such as chlorides, bromides, and iodides of tetramethylphosphonium, tetraethylphosphonium, tetrabutylphosphonium, and benzyltributylphosphonium; triethylamine; N,N-dimethylbenzylamine; tertiary amines such as 1,8-diazabicyclo[5.4.0]undecene and 1,4-diazabicyclo[2.2.2]octane; and imidazoles such as 2-ethyl-4-methylimidazolium and 2-phenylimidazolium. Two or more catalysts can also be used in combination. From the viewpoint of rapid reaction and high impurity reduction, sodium hydroxide, potassium hydroxide, triphenylphosphine, and DMP-30 are preferred. The amount of these catalysts used is not particularly limited, but 0.0001 to 0.01 moles are preferred relative to 1 mole of the phenolic hydroxyl group of the aforementioned aromatic hydroxyl compounds. The form of these catalysts is also not particularly limited; they can be used in aqueous solution or solid form.

[0364] Furthermore, the reaction between the aforementioned aliphatic dihydroxy compound's diglycidyl ether and the aforementioned aromatic hydroxy compound can be carried out in the absence of a solvent or in the presence of an organic solvent. Examples of usable organic solvents include: methyl cellosolve, ethyl cellosolve, toluene, xylene, methyl isobutyl ketone, dimethyl sulfoxide, propanol, butanol, etc. The amount of organic solvent used is typically 50-300% by mass relative to the total mass of the input raw materials, preferably 100-250% by mass. These organic solvents can be used alone or in combination. For rapid reaction, a solvent-free reaction is preferred; on the other hand, from the viewpoint of reducing impurities in the final product, dimethyl sulfoxide is preferred.

[0365] The reaction temperature for carrying out the aforementioned reaction is typically 50–180°C, and the reaction time is typically 1–10 hours. From the viewpoint of reducing impurities in the final product, the reaction temperature is preferably 100–160°C. Furthermore, if the obtained compound exhibits significant coloration, antioxidants or reducing agents can be added to suppress this. Antioxidants are not particularly limited, and examples include hindered phenolic compounds such as 2,6-dialkylphenol derivatives, divalent sulfur compounds, and phosphite compounds containing trivalent phosphorus atoms. Reducing agents are not particularly limited, and examples include hypophosphorous acid, phosphorous acid, thiosulfate, sulfurous acid, bisulfite, or their salts.

[0366] After the aforementioned reaction is completed, neutralization or washing can be performed until the pH of the reaction mixture reaches 3-7, preferably 5-7. Neutralization and washing can be carried out using conventional methods. For example, when using an alkaline catalyst, acidic substances such as hydrochloric acid, sodium dihydrogen phosphate, p-toluenesulfonic acid, or oxalic acid can be used as neutralizing agents. After neutralization or washing, if necessary, the solvent can be removed by distillation under reduced pressure and heating to concentrate the product and obtain the compound.

[0367] Regarding the reaction ratio of the aforementioned aliphatic divinyl ether to the aforementioned aromatic hydroxyl compound, it is preferable to react them in a range of 1 / 1.01 to 1 / 5.0 (molar ratio). From the viewpoint of achieving a good balance between the softness and heat resistance of the obtained cured product, (a1) / (a2) is preferably 1 / 1.02 to 1 / 3.0 (molar ratio).

[0368] The reaction between the aforementioned aliphatic dihydroxy compound's diglycidyl ether and the aforementioned aromatic hydroxy compound proceeds fully even without a catalyst, but from the viewpoint of selecting raw materials and increasing the reaction rate, a catalyst can be appropriately used. Examples of catalysts that can be used here include: inorganic acids such as sulfuric acid, hydrochloric acid, nitric acid, and phosphoric acid; organic acids such as toluenesulfonic acid, methanesulfonic acid, xylenesulfonic acid, trifluoromethanesulfonic acid, oxalic acid, formic acid, trichloroacetic acid, and trifluoroacetic acid; and Lewis acids such as aluminum chloride, ferric chloride, tin chloride, gallium chloride, titanium chloride, aluminum bromide, gallium bromide, boron trifluoride ether complexes, and boron trifluoride phenol complexes. The amount of catalyst used is typically in the range of 10 ppm to 1% by mass relative to the mass of the divinyl ether compound. In this case, it is preferable to select the type and amount of catalyst in a manner that does not induce a nucleation reaction of the vinyl group with the aromatic ring.

[0369] Furthermore, the reaction between the aforementioned aliphatic divinyl ether and the aforementioned aromatic hydroxyl compound can be carried out in the absence of a solvent or in the presence of an organic solvent. Examples of such solvents include: aromatic organic solvents such as benzene, toluene, and xylene; ketone organic solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; and alcohol organic solvents such as methanol, ethanol, isopropanol, and n-butanol. The amount of organic solvent used is typically 50-300% by mass relative to the total mass of the raw materials input, preferably 100-250% by mass. These organic solvents can be used alone or in combination.

[0370] The reaction temperature for carrying out the aforementioned reaction is typically 50–150°C, and the reaction time is typically 0.5–10 hours. To prevent the self-polymerization of the vinyl ether groups, it is preferable to carry out the reaction under an oxygen atmosphere.

[0371] After the aforementioned reaction is completed, if an organic solvent is used, it is removed under reduced pressure and heating. If a catalyst is used, it is deactivated as needed and removed by washing with water and filtration, thereby obtaining the compound.

[0372] The resulting compound with a terminal hydroxyl group is reacted with glycidyloxyphenylmaleimide, etc. Sodium hydroxide, potassium hydroxide, potassium carbonate, etc., can be used as catalysts, and toluene, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, acetonitrile, dimethylformamide, etc., can be used as solvents. The reaction temperature is room temperature to 200°C, and the reaction time is 1 to 24 hours. Afterwards, the catalyst can be removed by filtration, and the target compound can be obtained by extraction and solvent removal. The Diels-Alder reaction for this compound is as described above.

[0373] The aforementioned aliphatic hydroxyl compounds are not particularly limited, and examples include: 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, 1,11-undecanediol, 1,12-dodecanediol, 1,13-tridecanediol, 1,14-tetradecanediol, 1,15-pentadecanediol, 1,16-hexadecanediol, 2-methyl-1,11-undecanediol, 3-methyl-1,11-undecanediol, 2,6,10-trimethyl-1,11-undecanediol, polyethylene glycol, polypropylene glycol, polytetramethylenediol, polypentamethylenediol, polyhexamethylenediol, polyheptamethylenediol, etc., which can be used alone or in combination with two or more.

[0374] Among these, from the viewpoint of achieving an excellent balance between the softness and heat resistance of the resulting cured product, dihydroxy compounds with a polyether structure or a straight-chain alkylene chain having 12 to 14 carbon atoms are preferred, with polyethylene glycol, polypropylene glycol, polytetramethylene glycol, 1,12-dodecanediol, 1,13-tridecanediol, and 1,14-tetradecanediol being the most preferred.

[0375] The aforementioned dihaloalkyl compounds are not particularly limited, and examples include: 1,4-dichlorobutane, 1,5-dichloropentane, 1,6-dichlorohexane, 1,7-dichloroheptane, 1,8-dichlorooctane, 1,9-dichlorononane, 1,10-dichlorodecane, 1,11-dichloroundecane, 1,12-dichlorododecane, 1,4-dibromobutane, 1,5-dibromopentane, 1,6-dibromohexane, 1,7-dibromoheptane, 1,8-dibromooctane, 1,9-dibromononane, 1,10-dibromodecane, 1,11-dibromoundecane, 1,12-dibromododecane, etc. They can be used alone or in combination with two or more.

[0376] The aforementioned dihaloaryl compounds are not particularly limited, and examples include dichloroxylene, dichloromethylbiphenyl, dibromoxylene, and dibromomethylbiphenyl. They can be used alone or in combination with two or more.

[0377] Regarding the reaction ratio of the aforementioned aromatic dihydroxy compound with a dihaloalkyl compound or a dihaloaralkyl compound, it is preferable to react the compound in a range of 1 / 1.01 to 1 / 5.0 (molar ratio). From the viewpoint of achieving a good balance between the softness and heat resistance of the resulting cured product, (a1) / (a2) is preferably 1 / 1.02 to 1 / 3.0 (molar ratio).

[0378] The reaction of the aforementioned aromatic dihydroxy compound with a dihaloalkyl compound or a dihaloaralkyl compound is preferably carried out in the presence of a catalyst. Various catalysts can be used as the catalyst, such as alkali (earth) metal hydroxides like sodium hydroxide, potassium hydroxide, lithium hydroxide, and calcium hydroxide, and alkali metal carbonates like sodium carbonate and potassium carbonate. Two or more catalysts can also be used in combination. From the viewpoint of rapid reaction and high impurity reduction, sodium hydroxide, potassium hydroxide, and potassium carbonate are preferred. The amount of these catalysts used is not particularly limited, but 0.0001 to 10 moles are preferred relative to 1 mole of the phenolic hydroxyl group of the aforementioned aromatic dihydroxy compound. The form of these catalysts is also not particularly limited; they can be used in aqueous solution or in solid form.

[0379] Furthermore, the reaction of the aforementioned aromatic dihydroxy compounds with dihaloalkyl compounds or dihaloaralkyl compounds can be carried out in the absence of a solvent or in the presence of an organic solvent. Examples of usable organic solvents include toluene, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, acetonitrile, and dimethylformamide. The amount of organic solvent used is typically 50-300% by mass relative to the total mass of the raw materials input, preferably 100-1000% by mass. These organic solvents can be used alone or in combination.

[0380] The reaction temperature for carrying out the aforementioned reaction is typically room temperature to 150°C, and the reaction time is typically 1 to 24 hours. From the viewpoint of reducing impurities in the final product, the reaction temperature is preferably room temperature to 100°C.

[0381] The resulting compound with a terminal haloalkyl group is reacted with hydroxyphenyl maleimide, etc. Sodium hydroxide, potassium hydroxide, potassium carbonate, etc., can be used as catalysts, and toluene, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, acetonitrile, dimethylformamide, etc., can be used as solvents. The reaction temperature is room temperature to 200°C, and the reaction time is 1 to 24 hours. Afterwards, the catalyst can be removed by filtration, and the target compound can be obtained by extraction and solvent removal. The Diels-Alder reaction for this compound is as described above.

[0382] The diephilic intermediate prior to the Diels-Alder reaction can be represented by the following general formula (1)'.

[0383] [Chemistry 93]

[0384]

[0385] [In the formula, n and Z] 3 Same as above).

[0386] [Thermal Expansion Particles (D)]

[0387] The thermally expandable particles (D) contained in the epoxy resin composition of this embodiment can be either inorganic or organic. Examples of inorganic materials include thermally expandable graphite as disclosed in Japanese Patent Application Publication No. 2000-44219. Examples of organic thermally expandable particles include thermally expandable particles formed by microencapsulating a volatile expanding agent that is gaseous at a temperature below its softening point using a thermoplastic polymer as the outer shell.

[0388] Among these, from the viewpoint of excellent uniform dispersion and electrical insulation when used as an epoxy resin composition, thermally expandable microcapsules made of organic materials are preferred.

[0389] Furthermore, among these, from the viewpoint of the heat resistance, durability, and electrical conductivity of expandable particles, thermally expandable graphite is preferred.

[0390] Thermally expandable microcapsules

[0391] Methods for manufacturing the aforementioned thermally expandable microcapsules have been conventionally provided by Japanese Patent Publication No. 42-26524, but from the viewpoint of thermosetting the epoxy resin in this embodiment, heat resistance is preferred. Methods for manufacturing heat-resistant thermally expandable microcapsules include, for example, WO99 / 46320, WO99 / 43758, and Japanese Patent Application Publication No. 2002-226620.

[0392] That is, the preferred type of particle is one that does not expand thermally during the curing of epoxy resin but retains its original particle shape and expands thermally at high temperatures after use. From this point of view, it is preferable to use a thermally expandable microcapsule made of a polymer formed by polymerizing a nitrile monomer and a monomer having a carboxyl group as the outer shell polymer.

[0393] Furthermore, in order to impart heat resistance, monomers with amide groups and monomers with cyclic structures in the side chains are preferred.

[0394] As a method for obtaining the aforementioned heat-resistant, thermally expandable microcapsules, for example, the outer shell polymer can be prepared by appropriately incorporating a polymerization initiator into the above-mentioned components. Known polymerization initiators such as peroxides and azo compounds can be used. Examples include: azobisisobutyronitrile, benzoyl peroxide, lauroyl peroxide, diisopropyl peroxide dicarbonate, tert-butyl peroxide, and 2,2'-azobis(2,4-dimethylpentanonitrile). Oil-soluble polymerization initiators soluble in the polymerizable monomers used can be appropriately used. The glass transition temperature (Tg) of the polymer constituting the outer shell of the thermally expandable microcapsule is preferably 120°C or higher. The Tg of the polymer can be calculated from the Tg of each homopolymer constituting the monomer. Alternatively, it can be measured by differential scanning calorimetry (DSC) or the like.

[0395] The foaming agent contained within the microcapsules is a gaseous substance that becomes gaseous below the softening point of the outer shell polymer, and can be any known substance. Examples include: propane, propylene, butene, n-butane, isobutane, isopentane, neopentane, n-pentane, n-hexane, isohexane, heptane, octane, nonane, decane, petroleum ether, halides of methane, low-boiling-point liquids such as tetraalkylsilanes, and compounds such as AIBN that thermally decompose into a gaseous state upon heating. The appropriate foaming agent can be selected based on the desired temperature range for capsule foaming. The above-mentioned foaming agents can be used alone or in combination of two or more.

[0396] In addition, examples include fluorinated compounds such as HCF, HCFC, HFC, and HFE; commonly known as Freon, fluorocarbons, and fluoroethers. However, the use of these raises concerns about ozone layer depletion and global warming, and therefore should be avoided in today's society. In actual production, existing methods for manufacturing thermally expandable microcapsules are generally used. That is, inorganic particles such as silica, magnesium hydroxide, calcium phosphate, and aluminum hydroxide can be used as dispersants and stabilizers in aqueous solutions. Furthermore, condensation products of diethanolamine and aliphatic dicarboxylic acids, polyvinylpyrrolidone, methylcellulose, polyethylene oxide, polyvinyl alcohol, and various emulsifiers can be used as dispersants and stabilizers.

[0397] The average particle size of the thermally expandable microcapsules is 1 to 500 μm, preferably 3 to 100 μm, and more preferably 5 to 50 μm. The average particle size of the thermally expandable microcapsules can be determined, for example, by using a particle size distribution meter (LA-950, manufactured by HORIBA) to measure the volume average particle size.

[0398] Thermally expanding graphite

[0399] As a method for manufacturing the aforementioned thermally expandable graphite, Japanese Patent Application Laid-Open No. 2000-44219, etc., it is preferable to have heat resistance from the viewpoint of heat curing the epoxy resin in this embodiment. As a method for manufacturing heat-resistant thermally expandable graphite, Japanese Patent Application Laid-Open No. 2012-193053, etc., for example, can be provided.

[0400] For thermally expandable graphite, it is usually obtained by treating natural graphite, thermally decomposed graphite, and kish graphite with a mixture of concentrated sulfuric acid and a strong oxidizing agent (hereinafter referred to as acid treatment). After the formation of interlayer compounds in the graphite, it is washed with water, filtered, and dried. Common acid treatment methods are concentrated sulfuric acid-based methods such as concentrated sulfuric acid with nitric acid, concentrated sulfuric acid with potassium permanganate, concentrated sulfuric acid with perchloric acid, and concentrated sulfuric acid with hydrogen peroxide. In addition, methods using only fuming nitric acid are also known.

[0401] The thermally expandable graphite is selected based on the range of particle length and diameter. Therefore, commercially available expandable graphite is expressed in terms of particle size rather than length and diameter. Specifically, commercially available expandable graphite is graded using a sieve, and the characteristics of the expandable graphite product are indicated by information such as the percentage of particles passing through a certain mesh size, based on the sieve's mesh openings.

[0402] The preferred particle size of the thermally expandable graphite used in this system is 20 to 300 mesh, more preferably 30 to 200 mesh.

[0403] The aforementioned thermally expandable particle (D) can be directly mixed with the aforementioned epoxy resin (A) and epoxy resin (B), or a masterbatch made by dispersing the thermally expandable particle (D) in various resins at a high concentration can be used and mixed with the aforementioned epoxy resin (A) and epoxy resin (B).

[0404] Commercially available products can also be used as such thermally expandable particles (D). Examples of commercially available products include: Matsumoto Yushi Pharmaceutical Co., Ltd.'s microsphere (trade names: F-20D, F-30D, F-40D, FN-100D, FN-100MD, FN-100SD, FN-100SSD, FN-180D, FN-180SD, FN-180SSD, F-190D, F-260D); KUREHA's microsphere (trade names: H850D, H880D, S2340D, S2640D); Fuji Kogyo's expanded graphite (trade names: EXP-50S120K, EXP-50S150); Ito Graphite's expanded graphite (trade names: 953240L, 9550250); and AIR. WATER thermally expandable graphite (trade names: 50LTE-U, MZ-260, CA-60, SS-3, SS-3LA, etc.) is preferably selected from particles that do not thermally expand at the curing temperature of the epoxy resin composition but thermally expand at the heating temperature during disassembly.

[0405] From the viewpoint that the use ratio of the aforementioned thermally expandable particles (D) is such that they can expand sufficiently upon disassembly after use to exhibit a reduced adhesion effect without compromising the adhesion or the softness of the cured epoxy resin composition of this embodiment, it is preferable to use 3 to 40 parts by weight relative to a total of 100 parts by weight of the aforementioned epoxy resin (A) and the aforementioned epoxy resin (B), more preferably 5 to 30 parts by weight, even more preferably 6 to 20 parts by weight, and particularly preferably 7 to 15 parts by weight.

[0406] [Compound (I)]

[0407] The epoxy resin composition of this embodiment preferably further comprises a compound (I) that is reactive with the aforementioned compound (C) containing a glycidyl ether group. The compound (C) containing a glycidyl ether group of this embodiment can form an epoxy resin composition by combining it with the aforementioned compound (I). The epoxy resin composition is ideally suited for various electrical / electronic component applications such as adhesives, coatings, photoresists, printed wiring boards, and semiconductor sealing materials.

[0408] Compound (I) that reacts with the aforementioned compound (C) containing glycidyl ether groups can be exemplified by various known curing agents for epoxy resins, such as amine compounds, acid anhydrides, amide compounds, compounds containing phenolic hydroxyl groups, carboxylic acid compounds, and thiols. The curing agent can be appropriately selected based on the properties of the desired cured product; in particular, from the viewpoint of mechanical strength and adhesion to the substrate, compounds containing hydroxyl groups or amine groups are preferred.

[0409] Examples of the aforementioned amine compounds include: trimethylenediamine, ethylenediamine, N,N,N',N'-tetramethylethylenediamine, pentamethyldiethylenetriamine, trimethylenediamine, dipropylenediamine, N,N,N',N'-tetramethylpropylenediamine, tetramethyldiamine, pentamethyldiamine, hexamethylenediamine, trimethylhexamethylenediamine, N,N,N',N'-tetramethylhexamethylenediamine, N,N-dimethylcyclohexylamine, diethylenetriamine, and trimethylenediamine. Aliphatic amine compounds such as tetramethyltetramine, tetraethylenepentamine, dimethylaminopropylamine, diethylaminopropylamine, dibutylaminopropylamine, 1,4-diazabicyclo(2,2,2)octane (triethylenediamine), polyoxyethylenediamine, polyoxypropylenediamine, bis(2-dimethylaminoethyl) ether, dimethylaminoethoxyethoxyethanol, triethanolamine, dimethylaminohexanol, benzylmethylamine, dimethylbenzylamine, m-xylenediamine, α-methylbenzylmethylamine, etc.

[0410] Piperidine, piperazine, menthane diamine, isophorone diamine, methylmorpholine, ethylmorpholine, N,N',N”-tris(dimethylaminopropyl)hexahydro-triazine, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxospiro(5,5)undecane adduct, N-aminoethylpiperazine, trimethylaminoethylpiperazine, bis(4-aminocyclohexyl)methane, N,N'-dimethylpiperazine, 1,8-diazabicyclo-[5.4.0]-undecene (DBU) and other alicyclic and heterocyclic amine compounds;

[0411] Aromatic amine compounds such as o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, diaminodiphenylmethane, diaminodiphenyl sulfone, pyridine, and methylpyridine;

[0412] Modified amine compounds include epoxy addition polyamines, Michael addition polyamines, Mannich addition polyamines, thiourea addition polyamines, ketone-terminated polyamines, dicyandiamide, guanidine, organic acid hydrazides, diaminomaleonitrile, aminoimides, boron trifluoride-piperidine complexes, boron trifluoride-monoethylamine complexes, and other modified amine compounds.

[0413] Examples of the aforementioned acid anhydrides include: phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, maleic anhydride polypropylene glycol, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

[0414] Examples of compounds containing phenolic hydroxyl groups include: bis(4-hydroxyphenyl)methane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, and bis(4-hydroxyphenyl)sulfone, as well as bisphenols, phenolic varnish resins, cresol phenolic varnish resins, aromatic hydrocarbon formaldehyde resins modified with phenolic resins, dicyclopentadienylphenol addition-type resins, phenol aralkyl resins (Sylco resins), naphthol aralkyl resins, and trimethylolpropane resins. Tetraphenol ethane resin, naphthol phenolic varnish resin, naphthol-phenol co-condensed phenolic varnish resin, naphthol-cresol co-condensed phenolic varnish resin, biphenyl-modified phenolic resin (a polyphenol compound in which the phenolic nucleus is linked by dimethylene groups), biphenyl-modified naphthol resin (a polyphenol compound in which the phenolic nucleus is linked by dimethylene groups), aminotriazine-modified phenolic resin (a polyphenol compound in which the phenolic nucleus is linked by melamine, benzoguanamine, etc.), and alkoxy-containing aromatic ring-modified phenolic varnish resin (a polyphenol compound in which the phenolic nucleus and an alkoxy-containing aromatic ring are linked by formaldehyde), etc., are all polyphenolic compounds.

[0415] Examples of the aforementioned amide compounds include dicyandiamide and polyamidoamine. Examples of polyamidoamines include those obtained by reacting aliphatic dicarboxylic acids such as succinic acid, glutaric acid, adipic acid, pimelic acid, octanoic acid, and azelaic acid, fatty acids, and dimer acids with aliphatic polyamines or polyamines having polyoxyalkylene chains.

[0416] Examples of the aforementioned carboxylic acid compounds include carboxylic acid-terminated polyesters, polyacrylic acid, maleic acid-modified polypropylene glycol, and other carboxylic acid polymers.

[0417] As the aforementioned thiols, it is preferable that each molecule contains two or more thiols. Examples include: 3,3'-dithiodipropionic acid, trimethylolpropane tris(mercaptoacetate), pentaerythritol tetra(mercaptoacetate), ethylene glycol dimercaptoacetate, 1,4-bis(3-mercaptobutyryloxy)butane, tris[(3-mercaptopropionyloxy)-ethyl]-isocyanurate, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetra(3-mercaptopropionate), pentaerythritol tetra(3-mercaptobutyrylate), dipentaerythritol hexa(3-mercaptopropionate), 1,3,4,6-tetra(2-mercaptoethyl)glycourea, 4-butanedithiol, 1,6-hexanedithiol, 1,10-decanedithiol, etc.

[0418] When using these curing agents, only one type of curing agent can be used, or two or more types can be mixed. It should be noted that in applications such as underfill materials and general coatings, the aforementioned amine compounds, carboxylic acid compounds, and / or anhydride compounds are preferred. Furthermore, in applications such as adhesives and flexible wiring boards, amine compounds are preferred from the viewpoints of workability, curing properties, and long-term stability, with dicyandiamide being particularly preferred. Additionally, in applications such as semiconductor sealing materials, solid-state phenolic compounds are preferred from the viewpoint of the heat resistance of the cured product. Furthermore, in battery applications, aliphatic amines and thiols are preferred from the viewpoint of low-temperature curing.

[0419] Furthermore, from the viewpoint that the effects of the present invention can be further demonstrated, the compound (I) that is reactive with the aforementioned compound (C) containing a glycidyl ether group is preferably a compound containing a hydroxyl group or a compound containing an amine group that has a reversible bond.

[0420] Examples of compounds containing hydroxyl groups or amino groups that have reversible bonds include: compounds containing hydroxyl groups or amino groups formed by connecting structural units A' of one or more compounds containing hydroxyl groups or amino groups with structural units B' different from the aforementioned A' via A'-B'-A' and by bonding the aforementioned structural units A' and B' via reversible bonds.

[0421] As an example of the aforementioned reversible bond, a reversible bond identical to the reversible bond in compound (C) containing a glycidyl ether group in this embodiment can be cited.

[0422] [Other epoxy resins]

[0423] Furthermore, without compromising the effects of this embodiment, the epoxy resin composition of this embodiment may also be used in combination with other epoxy resins besides the aforementioned epoxy resin (A), epoxy resin (B), and compound (C) containing glycidyl ether groups. In this case, the total amount of epoxy resin (A), epoxy resin (B), and compound (C) containing glycidyl ether groups in the epoxy resin composition of this embodiment is preferably 30% by mass or more, and particularly preferably 40% by mass or more, among all epoxy resins.

[0424] As for other epoxy resins that can be used concurrently, there are no restrictions as long as they do not belong to epoxy resin (A), epoxy resin (B), or compounds containing glycidyl ether groups (C). Examples include: bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD ​​type epoxy resin, polyhydroxybenzene type epoxy resin, polyhydroxynaphthalene type epoxy resin, biphenyl type epoxy resin, tetramethylbiphenyl type epoxy resin, etc. (liquid epoxy resins); brominated epoxy resins such as brominated phenolic varnish type epoxy resin; solid bisphenol A type epoxy resin, phenolic varnish type epoxy resin, cresol phenolic varnish type epoxy resin, etc. Phenylmethane type epoxy resin, tetraphenylethane type epoxy resin, dicyclopentadiene-phenol addition reaction type epoxy resin, phenol aralkyl type epoxy resin, phenylene ether type epoxy resin, naphthylene ether type epoxy resin, naphthol phenolic varnish type epoxy resin, naphthol aralkyl type epoxy resin, naphthol-phenol cocondensed phenolic varnish type epoxy resin, naphthol-cresol cocondensed phenolic varnish type epoxy resin, aromatic hydrocarbon formaldehyde resin modified phenolic resin type epoxy resin, biphenyl modified phenolic varnish type epoxy resin, etc., can be used alone or in combination of two or more types. It is preferred to select the appropriate type based on the target application, the physical properties of the cured product, etc.

[0425] The concentration of reversible bonds in the epoxy resin composition of this embodiment is preferably 0.10 mmol / g or more relative to the total mass of the curable components in the epoxy resin composition. With this configuration, the adhesion, flexibility, and disintegration of the cured product obtained from the epoxy resin composition are all improved. The concentration of the aforementioned reversible bonds is more preferably 0.10 to 3.00 mmol / g, and even more preferably 0.15 to 2.00 mmol / g. Furthermore, in the case where the compound (C) containing glycidyl ether groups in this embodiment has multiple reversible bonds, or when the aforementioned compound containing hydroxyl groups with reversible bonds is used alone as a curing agent or in combination with other curing agents, the total concentration of these reversible bonds relative to the total mass of the curable components in the epoxy resin composition is preferably 0.10 mmol / g or more, more preferably 0.10 to 3.00 mmol / g, and even more preferably 0.15 to 2.00 mmol / g. It should be noted that the concentration of reversible bonds can be appropriately selected based on factors such as the glass transition temperature of the target cured product, defined by the tanδ peak of a dynamic viscoelasticity analyzer (DMA). For example, when using the glass transition temperature as a reference, if the glass transition temperature of the cured product is near room temperature, sufficient adhesiveness, flexibility, and disassembly properties are easily exhibited even at low concentrations within the preferred range. On the other hand, if the glass transition temperature of the target cured product exceeds 100°C as a standard, it is easy to exhibit functionality at high concentrations within the preferred range. However, in temperature regions exceeding the glass transition temperature measured by DMA, molecular mobility is generally high, and sufficient adhesiveness, flexibility, and disassembly properties are easily exhibited even at low concentrations of compounds (C) containing glycidyl ether groups. Therefore, the performance of adhesiveness, flexibility, and disassembly properties can be adjusted, for example, by appropriately adjusting the aging temperature for curing and the heating temperature for disassembly. Thus, the relationship between the glass transition temperature of the cured product and the concentration of reversible bonds is not limited to these.

[0426] The ratio of the total amount of glycidyl ether groups to the total amount of active groups that can react with the glycidyl ether groups in the epoxy resin composition of this embodiment is not particularly limited. From the viewpoint of good mechanical properties and other aspects of the obtained cured product, the amount of active groups that can react with the glycidyl ether groups is preferably 0.4 to 1.5 equivalents relative to 1 equivalent of the total amount of glycidyl ether groups in the resin composition.

[0427] [Curing Accelerator]

[0428] The epoxy resin composition of this embodiment may also include a curing accelerator. Various curing accelerators can be used as such accelerators, including, for example, urea compounds, phosphorus compounds, tertiary amines, imidazoles, imidazolines, organic acid metal salts, Lewis acids, and amine complexes. When used as an adhesive, urea compounds are preferred from the viewpoint of excellent workability and low-temperature curing properties, and 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) is particularly preferred. When used as a semiconductor sealing material, triphenylphosphine is preferred among phosphorus compounds from the viewpoint of excellent curability, heat resistance, electrical properties, and moisture resistance reliability, and 1,8-diazabicyclo-[5.4.0]-undecene is preferred among tertiary amines.

[0429] Examples of the aforementioned phosphorus compounds include: alkylphosphines such as ethylphosphine and butylphosphine, primary phosphines such as phenylphosphine; dialkylphosphines such as dimethylphosphine and dipropylphosphine; secondary phosphines such as diphenylphosphine and methylethylphosphine; and tertiary phosphines such as trimethylphosphine, triethylphosphine, and triphenylphosphine.

[0430] Examples of imidazoles mentioned above include: imidazole, 1-methylimidazolium, 2-methylimidazolium, 3-methylimidazolium, 4-methylimidazolium, 5-methylimidazolium, 1-ethylimidazolium, 2-ethylimidazolium, 3-ethylimidazolium, 4-ethylimidazolium, 5-ethylimidazolium, 1-n-propylimidazolium, 2-n-propylimidazolium, 1-isopropylimidazolium, 2-isopropylimidazolium, 1-n-butylimidazolium, 2-n-butylimidazolium, 1-isobutylimidazolium, 2-isobutylimidazolium, 2-undecyl-1H-imidazolium, 2-heptadecanyl-1H-imidazolium, 1,2-dimethylimidazolium, 1,3-dimethylimidazolium, 2,4-dimethylimidazolium, 2-ethyl-4-methylimidazolium, 1-phenylimidazolium, 2-phenyl-1H-imidazolium, 4-methyl-2 -Phenylacetyl-1H-imidazolium, 2-Phenylacetyl-4-methylimidazolium, 1-benzyl-2-methylimidazolium, 1-benzyl-2-phenylimidazolium, 1-cyanoethyl-2-methylimidazolium, 1-cyanoethyl-2-ethyl-4-methylimidazolium, 1-cyanoethyl-2-undecylimidazolium, 1-cyanoethyl-2-phenylimidazolium, 2-phenylimidazolium isocyanuric acid adduct, 2-methylimidazolium isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazolium, 2-phenyl-4-methyl-5-hydroxymethylimidazolium, 1-cyanoethyl-2-phenyl-4,5-di(2-cyanoethoxy)methylimidazolium, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 1-benzyl-2-phenylimidazolium hydrochloride, etc.

[0431] Examples of the aforementioned imidazoline compounds include 2-methylimidazoline and 2-phenylimidazoline.

[0432] Examples of the aforementioned urea compounds include p-chlorophenyl-N,N-dimethylurea, 3-phenyl-1,1-dimethylurea, 3-(3,4-dichlorophenyl)-N,N-dimethylurea, and N-(3-chloro-4-methylphenyl)-N',N'-dimethylurea.

[0433] [Other thermosetting resins, thermoplastic resins]

[0434] Furthermore, without hindering the effects of this embodiment, the epoxy resin composition of this embodiment may also be used in combination with other thermosetting resins and thermoplastic resins.

[0435] Other thermosetting resins include, for example, cyanate ester resins, resins having a benzoxazine structure, reactive ester resins, vinyl benzyl compounds, acrylic compounds, copolymers of styrene and maleic anhydride, etc. When using the aforementioned other thermosetting resins, there are no particular limitations on the amount used, as long as it does not hinder the effect of this embodiment; preferably, it is in the range of 1 to 50 parts by weight of 100 parts by weight of the epoxy resin composition.

[0436] Examples of the aforementioned cyanate ester resins include: bisphenol A type cyanate ester resin, bisphenol F type cyanate ester resin, bisphenol E type cyanate ester resin, bisphenol S type cyanate ester resin, bisphenol sulfide type cyanate ester resin, phenylene ether type cyanate ester resin, naphthylene ether type cyanate ester resin, biphenyl type cyanate ester resin, tetramethylbiphenyl type cyanate ester resin, polyhydroxynaphthalene type cyanate ester resin, phenol phenolic varnish type cyanate ester resin, cresol phenolic varnish type cyanate ester resin, triphenylmethane type cyanate ester resin, tetraphenylethane type cyanate ester resin, dicyclopentadiene-phenol addition reaction type cyanate ester resin, phenol aralkyl type cyanate ester resin, naphthol phenolic varnish type cyanate ester resin, naphthol aralkyl type cyanate ester resin, naphthol-phenol cocondensed phenolic varnish type cyanate ester resin, naphthol-cresol cocondensed phenolic varnish type cyanate ester resin, aromatic hydrocarbon formaldehyde resin modified phenolic resin type cyanate ester resin, biphenyl modified phenolic varnish type cyanate ester resin, anthracene type cyanate ester resin, etc. They can be used individually or in combination of two or more.

[0437] Among these cyanate resins, especially in terms of obtaining cured products with excellent heat resistance, bisphenol A type cyanate resin, bisphenol F type cyanate resin, bisphenol E type cyanate resin, polyhydroxynaphthalene type cyanate resin, naphthyl ether type cyanate resin, and phenolic varnish type cyanate resin are preferred. In terms of obtaining cured products with excellent dielectric properties, dicyclopentadiene-phenol addition reaction type cyanate resin is preferred.

[0438] There are no particular limitations on the type of resin that has a benzoxazine structure. Examples include: the reaction product of bisphenol F with formalin and aniline (Fa-type benzoxazine resin); the reaction product of diaminodiphenylmethane with formalin and phenol (Pd-type benzoxazine resin); the reaction product of bisphenol A with formalin and aniline; the reaction product of dihydroxydiphenyl ether with formalin and aniline; the reaction product of diaminodiphenyl ether with formalin and phenol; the reaction product of dicyclopentadiene-phenol addition-type resin with formalin and aniline; the reaction product of phenolphthalein with formalin and aniline; and the reaction product of diphenyl sulfide with formalin and aniline. These resins can be used individually or in combination of two or more.

[0439] There are no particular limitations on the aforementioned reactive ester resins, but compounds with two or more highly reactive ester groups per molecule, such as phenolic esters, thiophenol esters, N-hydroxyamine esters, and heterocyclic hydroxyl esters, are generally preferred. The aforementioned reactive ester resins are preferably obtained through a condensation reaction of carboxylic acid compounds and / or thiocarboxylic acid compounds with hydroxyl compounds and / or thiols. Particularly from the viewpoint of improving heat resistance, reactive ester resins obtained from carboxylic acid compounds or their halides with hydroxyl compounds are preferred, and reactive ester resins obtained from carboxylic acid compounds or their halides with phenolic compounds and / or naphthol compounds are more preferred. Examples of carboxylic acid compounds include, for example, benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid, etc., or their halides. Examples of phenolic or naphthol compounds include: hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, dihydroxydiphenyl ether, phenolphthalein, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthol, 1,6-dihydroxynaphthol, 2,6-dihydroxynaphthol, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucinol, pyroglucinol, dicyclopentadiene-phenol addition resin, etc.

[0440] As an active ester resin, the preferred active ester resins are those containing a dicyclopentadiene-phenol addition structure, active ester resins containing a naphthalene structure, active ester resins that are acetylated derivatives of phenolic varnishes, and active ester resins that are benzoyl derivatives of phenolic varnishes. From the viewpoint of superior improvement in peel strength, active ester resins containing a dicyclopentadiene-phenol addition structure and active ester resins containing a naphthalene structure are more preferred.

[0441] Furthermore, it can also be used in combination with various phenolic varnish resins, addition polymerization resins of alicyclic dienes such as dicyclopentadiene and phenolic compounds, modified phenolic varnish resins of compounds containing phenolic hydroxyl groups and aromatic compounds containing alkoxy groups, phenolic aralkyl resins (Sylco resins), naphthol aralkyl resins, trimethylolmethane resins, tetraphenol ethane resins, biphenyl-modified phenolic resins, biphenyl-modified naphthol resins, aminotriazine-modified phenolic resins, and various vinyl polymers.

[0442] More specifically, the aforementioned phenolic varnish resins can be exemplified as polymers obtained by reacting compounds containing phenolic hydroxyl groups, such as phenol, phenylphenol, resorcinol, biphenyl, bisphenol A, bisphenol F, naphthol, and dihydroxynaphthalene, with aldehyde compounds under acid catalytic conditions.

[0443] Examples of the aforementioned vinyl polymers include: homopolymers or copolymers of vinyl compounds such as polyhydroxystyrene, polystyrene, polyvinylnaphthalene, polyvinylanthracene, polyvinylcarbazole, polyindene, polyacenaphthene, polynorbornene, polycyclodecene, polytetracyclododecene, polynortricyclene, and poly(meth)acrylate.

[0444] Thermoplastic resins are resins that can be melted and molded by heating. Specific examples include: polyethylene resin, polypropylene resin, polystyrene resin, rubber-modified polystyrene resin, acrylonitrile-butadiene-styrene (ABS) resin, acrylonitrile-styrene (AS) resin, polymethyl methacrylate resin, acrylic resin, polyvinyl chloride resin, polyvinylidene chloride resin, polyethylene terephthalate resin, ethylene vinyl alcohol resin, cellulose acetate resin, ionomer resin, polyacrylonitrile resin, polyamide resin, polyacetal resin, polybutylene terephthalate resin, polylactic acid resin, polyphenylene ether resin, modified polyphenylene ether resin, polycarbonate resin, polysulfone resin, polyphenylene sulfide resin, polyetherimide resin, polyethersulfone resin, polyarylate resin, thermoplastic polyimide resin, polyamide-imide resin, polyetheretherketone resin, polyketone resin, liquid crystal polyester resin, fluoropolymer resin, syndiotactic polystyrene resin, and cyclic polyolefin resin, etc. These thermoplastic resins can be used in combination with one or more.

[0445] When using these other resins, the ratio of the compound (C) containing glycidyl ether groups in this embodiment to other resins can be set arbitrarily according to the application. From the perspective of excellent adhesion, softness and disassembly when the cured product is made, the ratio of other resins is preferably 0.5 to 100 parts by mass relative to 100 parts by mass of the compound (C) containing glycidyl ether groups in this embodiment.

[0446] [Non-halogen flame retardants]

[0447] When used in applications requiring high flame retardancy of the epoxy resin composition of this embodiment, a non-halogenated flame retardant that does not substantially contain halogen atoms may also be used.

[0448] Examples of non-halogenated flame retardants include phosphorus-based flame retardants, nitrogen-based flame retardants, organosilicon-based flame retardants, inorganic flame retardants, and organometallic salt-based flame retardants. There are no restrictions on their use; they can be used alone, or multiple flame retardants of the same system can be used together. In addition, flame retardants of different systems can be used in combination.

[0449] The aforementioned phosphorus-based flame retardants can be either inorganic or organic. Examples of inorganic compounds include: red phosphorus, monoammonium phosphate, diammonium phosphate, triammonium phosphate, ammonium polyphosphate, and other ammonium phosphates, as well as inorganic nitrogen- and phosphorus-containing compounds such as phosphoramides.

[0450] In addition, for the purpose of preventing hydrolysis, it is preferable to perform surface treatment on the aforementioned red phosphorus. Examples of surface treatment methods include: (i) coating treatment with inorganic compounds such as magnesium hydroxide, aluminum hydroxide, zinc hydroxide, titanium hydroxide, bismuth oxide, bismuth hydroxide, bismuth nitrate, or mixtures thereof; (ii) coating treatment with a mixture of inorganic compounds such as magnesium hydroxide, aluminum hydroxide, zinc hydroxide, and titanium hydroxide and thermosetting resins such as phenolic resin; and (iii) double coating treatment with thermosetting resins such as phenolic resin on a film of inorganic compounds such as magnesium hydroxide, aluminum hydroxide, zinc hydroxide, and titanium hydroxide.

[0451] Regarding the aforementioned organophosphorus compounds, in addition to general organophosphorus compounds such as phosphate esters, phosphonic acids, hypophosphonic acids, phosphine oxides, phosphine compounds, and organic nitrogen- and phosphorus-containing compounds, examples include: cyclic organophosphorus compounds such as 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, and 10-(2,7-dihydroxynaphthyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, as well as derivatives obtained by reacting them with compounds such as epoxy resins and phenolic resins.

[0452] The amount of these phosphorus-based flame retardants can be appropriately selected based on the type of phosphorus-based flame retardant, other components of the resin composition, and the desired degree of flame retardancy. Furthermore, for example, in 100 parts by weight of a resin composition containing all components such as non-halogenated flame retardants, fillers, and additives, if red phosphorus is used as the non-halogenated flame retardant, it is preferable to use 0.1 to 2.0 parts by weight; if an organophosphorus compound is used, it is also preferable to use 0.1 to 10.0 parts by weight, and more preferably 0.5 to 6.0 parts by weight.

[0453] In addition, when using the aforementioned phosphorus-based flame retardant, it is also possible to use hydrotalcite, magnesium hydroxide, boron compounds, zirconium oxide, black dye, calcium carbonate, zeolite, zinc molybdate, activated carbon, etc., in conjunction with the phosphorus-based flame retardant.

[0454] Examples of nitrogen-based flame retardants include triazine compounds, cyanuric acid compounds, isocyanuric acid compounds, and phenothiazine compounds, with triazine compounds, cyanuric acid compounds, and isocyanuric acid compounds being preferred.

[0455] Regarding the aforementioned triazine compounds, in addition to melamine, acetylguanidine, benzoguanidine, mellon, succinylguanidine, ethylenedimelamine, polyphosphate melamine, triguanidine, etc., examples include: (1) aminotriazine sulfate compounds such as amidine sulfate melamine, mellon sulfate, succinylguanidine, etc.; (2) co-condensates of phenols such as phenol, cresol, xylenol, butylphenol, nonylphenol, etc., with melamines such as melamine, benzoguanidine, acetylguanidine, methylguanidine, etc., and formaldehyde; (3) mixtures of phenolic resins such as the co-condensate of (2) and phenol-formaldehyde condensate; and (4) triazine compounds obtained by further modifying (2) and (3) with tung oil, isomerized linseed oil, etc.

[0456] Examples of the aforementioned cyanuric acid compounds include cyanuric acid and melamine cyanurate.

[0457] The amount of the aforementioned nitrogen-based flame retardant can be appropriately selected based on the type of nitrogen-based flame retardant, other components of the resin composition, and the desired degree of flame retardancy. Furthermore, for example, in 100 parts by weight of a resin composition containing a non-halogenated flame retardant and all other components such as fillers and additives, it is preferable to use 0.05 to 10 parts by weight, and more preferably 0.1 to 5 parts by weight.

[0458] In addition, when using the aforementioned nitrogen-based flame retardants, metal hydroxides, molybdenum compounds, etc., can also be used in combination.

[0459] The aforementioned silicone-based flame retardants can be used without particular restriction as long as they are organic compounds containing silicon atoms, such as silicone oil, silicone rubber, and silicone resin. The amount of the aforementioned silicone-based flame retardant can be appropriately selected based on the type of silicone-based flame retardant, other components of the resin composition, and the desired degree of flame retardancy. For example, in 100 parts by weight of a resin composition containing a non-halogenated flame retardant and all other components such as fillers and additives, it is preferable to use 0.05 to 20 parts by weight. Furthermore, when using the aforementioned silicone-based flame retardant, molybdenum compounds, alumina, etc., can be used in combination.

[0460] Examples of inorganic flame retardants include: metal hydroxides, metal oxides, metal carbonate compounds, metal powders, boron compounds, and low-melting-point glasses.

[0461] Examples of the aforementioned metal hydroxides include: aluminum hydroxide, magnesium hydroxide, dolomite, hydrotalcite, calcium hydroxide, barium hydroxide, zirconium hydroxide, etc.

[0462] Examples of the aforementioned metal oxides include: zinc molybdate, molybdenum trioxide, zinc stannate, tin oxide, aluminum oxide, iron oxide, titanium oxide, manganese oxide, zirconium oxide, zinc oxide, molybdenum oxide, cobalt oxide, bismuth oxide, chromium oxide, nickel oxide, copper oxide, and tungsten oxide.

[0463] Examples of the aforementioned metal carbonate compounds include: zinc carbonate, magnesium carbonate, calcium carbonate, barium carbonate, basic magnesium carbonate, aluminum carbonate, iron carbonate, cobalt carbonate, and titanium carbonate.

[0464] Examples of the aforementioned metal powders include: aluminum, iron, titanium, manganese, zinc, molybdenum, cobalt, bismuth, chromium, nickel, copper, tungsten, and tin.

[0465] Examples of the aforementioned boron compounds include zinc borate, zinc metaborate, barium metaborate, boric acid, and borax.

[0466] Examples of low-melting-point glasses mentioned above include: Cepree (Bokusui-Brown), hydrated glasses (SiO2-MgO-H2O), PbO-B2O3 series, ZnO-P2O5-MgO series, P2O5-B2O3-PbO-MgO series, P-Sn-OF series, PbO-V2O5-TeO2 series, Al2O3-H2O series, lead borosilicate series, and other glassy compounds.

[0467] The amount of the aforementioned inorganic flame retardant can be appropriately selected based on the type of inorganic flame retardant, other components of the resin composition, and the desired degree of flame retardancy. Furthermore, for example, in 100 parts by weight of a resin composition containing a non-halogenated flame retardant and all other components such as fillers and additives, it is preferable to use 0.05 to 20 parts by weight, and more preferably 0.5 to 15 parts by weight.

[0468] Examples of organometallic salt flame retardants include: ferrocene, acetylacetone metal complexes, organometallic carbonyl compounds, organocobalt salts, organosulfonic acid metal salts, and compounds formed by ionic or coordinate bonding of metal atoms with aromatic or heterocyclic compounds.

[0469] The amount of the aforementioned organometallic salt flame retardant can be appropriately selected based on the type of organometallic salt flame retardant, other components of the resin composition, and the desired degree of flame retardancy. Furthermore, for example, in 100 parts by weight of a resin composition containing a non-halogenated flame retardant and all other components such as fillers and additives, it is preferable to use a range of 0.005 parts by weight to 10 parts by weight.

[0470] [filler]

[0471] The epoxy resin composition of this embodiment may also contain fillers that are not part of the aforementioned thermally expandable particles (D) of this embodiment. Examples of fillers include inorganic fillers and organic fillers. Examples of inorganic fillers include, for instance, inorganic microparticles.

[0472] As inorganic microparticles, for example, those with excellent heat resistance include alumina, magnesium oxide, titanium dioxide, zirconium oxide, and silica (quartz, fumed silica, settled silica, silicic anhydride, fused silica, crystalline silica, ultrafine amorphous silica, etc.); those with excellent thermal conductivity include boron nitride, aluminum nitride, alumina, titanium oxide, magnesium oxide, zinc oxide, silica, and diamond; those with excellent electrical conductivity include metal fillers and / or metal-coated fillers using elemental metals or alloys (e.g., iron, copper, magnesium, aluminum, gold, silver, platinum, zinc, manganese, stainless steel, etc.); and those with excellent barrier properties include mica, clay, kaolin, talc, zeolite, wollastonite, chlorite, potassium titanate, and magnesium sulfate. Sepiolite, vermiculite, aluminum borate, calcium carbonate, titanium dioxide, barium sulfate, zinc oxide, and magnesium hydroxide; high-refractive-index inorganic particles include barium titanate, zirconium oxide, and titanium dioxide; photocatalytic inorganic particles include photocatalytic metals such as titanium, cerium, zinc, copper, aluminum, tin, indium, phosphorus, carbon, sulfur, ruthenium, nickel, iron, cobalt, silver, molybdenum, strontium, chromium, barium, and lead, as well as their compounds and oxides; high-wear-resistance inorganic particles include metals such as silicon dioxide, aluminum oxide, zirconium oxide, and magnesium oxide, as well as their compounds and oxides; high-conductivity inorganic particles include metals such as silver and copper, tin oxide, and indium oxide; high-insulation inorganic particles include silicon dioxide; and high-UV-shielding inorganic particles include titanium dioxide and zinc oxide. These inorganic particles can be selected appropriately according to the application, and can be used individually or in combination. In addition to the properties mentioned in the examples, the aforementioned inorganic particles also possess various other properties, so they can be selected appropriately based on their intended use.

[0473] For example, when using silica as an inorganic microparticle, there are no particular limitations; known silica microparticles such as powdered silica and colloidal silica can be used. Examples of commercially available powdered silica microparticles include: AEROSIL 50 and 200 manufactured by AEROSIL Co., Ltd. (Japan); SHIELDEX H31, H32, H51, H52, H121, and H122 manufactured by Asahi Glass Co., Ltd.; E220A and E220 manufactured by Nippon Silica Industry Co., Ltd.; SYLYSIA 470 manufactured by Fuji SYLYSIA Co., Ltd.; and SG FLAKE manufactured by Nippon Sheet Glass Co., Ltd.

[0474] In addition, commercially available colloidal silica products include, for example, Nissan Chemical Industries, Ltd.'s methanol silica sol, IPA-ST, MEK-ST, NBA-ST, XBA-ST, DMAC-ST, ST-UP, ST-OUP, ST-20, ST-40, ST-C, ST-N, ST-O, ST-50, ST-OL, etc.

[0475] Surface-modified silica microparticles can also be used. Examples include silica microparticles obtained by surface treatment of the aforementioned silica microparticles with a reactive silane coupling agent having a hydrophobic group, and silica microparticles obtained by modification with a compound having a (meth)acryloyl group. Examples of commercially available powdered silica modified with a compound having a (meth)acryloyl group include AEROSIL RM50 and R711 manufactured by AEROSIL Co., Ltd. of Japan. Examples of commercially available colloidal silica modified with a compound having a (meth)acryloyl group include MIBK-SD manufactured by Nissan Chemical Industries, Ltd.

[0476] The shape of the aforementioned silica particles is not particularly limited, and spherical, hollow, porous, rod-shaped, plate-shaped, fibrous, or irregularly shaped silica particles can be used. In addition, the primary particle size is preferably in the range of 5 to 200 nm.

[0477] As titanium dioxide microparticles, not only extender pigments can be used, but also ultraviolet light-responsive photocatalysts, such as anatase titanium dioxide, rutile titanium dioxide, and brookite titanium dioxide. Furthermore, particles designed to respond to visible light by doping the crystal structure of titanium dioxide with different elements can also be used. Suitable elements for doping titanium dioxide include anionic elements such as nitrogen, sulfur, carbon, fluorine, and phosphorus, and cationic elements such as chromium, iron, cobalt, and manganese. In terms of form, they can be powders, sols or slurries dispersed in organic solvents or water. Examples of commercially available powdered titanium dioxide microparticles include AEROSIL P-25 manufactured by AEROSIL Co., Ltd. of Japan and ATM-100 manufactured by TAYCA Co., Ltd. Examples of commercially available slurry-type titanium dioxide microparticles include TAYCA Co., Ltd. TKD-701.

[0478] [Fibrous matrix]

[0479] The epoxy resin composition of this embodiment may further contain a fibrous matrix. The aforementioned fibrous matrix is ​​not particularly limited, but is preferably a fibrous matrix used for fiber-reinforced resins, including inorganic fibers and organic fibers.

[0480] In addition to inorganic fibers such as carbon fiber, glass fiber, boron fiber, alumina fiber, and silicon carbide fiber, other examples of inorganic fibers include: carbon fiber, activated carbon fiber, graphite fiber, tungsten carbide fiber, silicon carbide fiber, ceramic fiber, natural fiber, mineral fibers such as basalt, boron nitride fiber, boron carbide fiber, and metal fiber. Examples of metal fibers include: aluminum fiber, copper fiber, brass fiber, stainless steel fiber, and steel fiber.

[0481] Examples of organic fibers include: synthetic fibers made of resins such as polybenzoxazole, aromatic polyamide, PBO (poly(p-phenylenebenzoxazole)), polyphenylene sulfide, polyester, acrylic acid, polyamide, polyolefin, polyvinyl alcohol, and polyarylate; natural fibers such as cellulose, pulp, cotton, wool, and silk; and regenerated fibers such as proteins, polypeptides, and alginic acid.

[0482] Carbon fiber and glass fiber are preferred due to their wide range of industrial applications. One type or multiple types may be used simultaneously.

[0483] The aforementioned fibrous matrix can be an aggregate of fibers, which can be continuous or discontinuous, and can be woven or nonwoven. Alternatively, it can be a fiber bundle formed by neatly arranging fibers in one direction, or a sheet formed by arranging fiber bundles. Furthermore, it can be a three-dimensional shape formed by giving the aggregate of fibers thickness.

[0484] [Dispersion medium]

[0485] To adjust the amount of solids and viscosity of the resin composition, a dispersion medium can be used in the epoxy resin composition of this embodiment. As a dispersion medium, any liquid medium that does not impair the effects of this embodiment is acceptable; examples include various organic solvents and liquid organic polymers.

[0486] Examples of organic solvents mentioned above include ketones such as acetone, methyl ethyl ketone (MEK), and methyl isobutyl ketone (MIBK); cyclic ethers such as tetrahydrofuran (THF) and dioxolane; esters such as methyl acetate, ethyl acetate, and butyl acetate; aromatics such as toluene and xylene; alcohols such as carbitol, cellosolve, methanol, isopropanol, butanol, and propylene glycol monomethyl ether. These solvents can be used individually or in combination. Furthermore, from the perspectives of volatility and solvent recovery during coating, methyl ethyl ketone is preferred.

[0487] The aforementioned liquid organic polymers are liquid organic polymers that do not directly contribute to the curing reaction. Examples include: acrylic polymers (FLOWLEN WK-20: Kyoeisha), amine salts of specially modified phosphate esters (HIPLAAD ED-251: Kusunoki Kasei), and modified acrylic block copolymers (DISPERBYK 2000: BYK Chemicals).

[0488] [Other coordination compounds]

[0489] The resin composition of this embodiment may also contain other complexes. Examples include: catalysts, polymerization initiators, inorganic pigments, organic pigments, extender pigments, clay minerals, waxes, surfactants, stabilizers, flow modifiers, coupling agents, dyes, leveling agents, rheology control agents, ultraviolet absorbers, antioxidants, flame retardants, plasticizers, reactive diluents, etc.

[0490] By curing the resin composition of this embodiment, a cured product can be obtained. Curing can be performed at room temperature or by heating. In the case of heat curing, curing can be performed by a single heating step or through multiple heating stages.

[0491] Alternatively, the epoxy resin composition of this embodiment can also be cured using active energy rays. In this case, a photocationic polymerization initiator can be used as the polymerization initiator. Visible light, ultraviolet light, X-rays, electron beams, etc., can be used as the active energy rays.

[0492] Examples of photocationic polymerization initiators include aryl-sulfonium salts and aryl-iodonium salts. Specifically, arylsulfonium hexafluorophosphate, arylsulfonium hexafluoroantimonate, arylsulfonium tetra(pentafluoro)borate, and tri(alkylphenyl)sulfonium hexafluorophosphate can be used. Photocationic polymerization initiators can be used alone or in combination of two or more.

[0493] [Preparation method of epoxy resin composition]

[0494] The epoxy resin composition of this embodiment can be prepared simply by uniformly mixing the aforementioned components, and the method is not particularly limited. For example, it can be prepared by uniformly mixing using a pot mill, ball mill, bead mill, roller mill, homogenizer, ultramill, homogenizer, universal mixer, Banbury mixer, kneader, etc.

[0495] Regarding the epoxy resin composition of this embodiment, the epoxy resin (A) of this embodiment, the epoxy resin (B) of this embodiment, the compound (C) containing glycidyl ether groups of this embodiment, the thermally expanding particles (D) of this embodiment, and a compound (I) that is reactive with the compound (C) containing glycidyl ether groups as needed, as well as a curing agent, filler, fibrous matrix, dispersion medium, and resin other than the aforementioned compounds, which can be used together as needed, are dissolved in a dispersion medium such as an organic solvent. After dissolution, the solvent is removed by distillation, and the epoxy resin composition is obtained by vacuum drying using a vacuum oven or the like. Furthermore, the epoxy resin composition of this embodiment can be a composition in which the aforementioned constituent materials are uniformly mixed. In this case, it is preferable to use a mixer or the like for uniform mixing. The proportions of each constituent material can be appropriately adjusted according to the desired mechanical strength, heat resistance, and other properties of the cured product. Furthermore, the mixing order of the specific constituent materials in the preparation of the epoxy resin composition is not particularly limited.

[0496] (cured material)

[0497] The cured product of this embodiment is obtained by curing a compound (I) that is reactive with the aforementioned compound (C) containing a glycidyl ether group using the compound (C) of this embodiment. The curing method can be appropriately selected from known methods depending on the properties of the compound (I) that is reactive with the aforementioned compound (C) containing a glycidyl ether group.

[0498] The cured product of this embodiment is cured by the compound (C) containing glycidyl ether group of this embodiment as described above, and thus exhibits an appropriate crosslinking density, thereby maintaining good mechanical strength.

[0499] The structure of the obtained solidified material can be confirmed by infrared absorption (IR) spectroscopy such as Fourier transform infrared spectroscopy (FT-IR), elemental analysis, X-ray scattering, etc.

[0500] As described above, the cured product of one embodiment of this invention can be obtained by using the compound (C) containing glycidyl ether groups of this embodiment as a component of the epoxy resin composition. Alternatively, an intermediate of the compound (C) containing glycidyl ether groups, namely the aforementioned conjugated diene intermediate, can be used in combination with a compound that can undergo an addition reaction via the Diels-Alder reaction. During the curing process, the compound (C) containing glycidyl ether groups is formed (while being synthesized in situ), and a cured product is formed.

[0501] For example, if the compound represented by formula (4)', a furan having a glycidyl ether group, and a compound (I) that is reactive with the aforementioned compound (C) containing a glycidyl ether group are used as necessary raw materials for a curing reaction, then during the curing reaction, the compound (C) containing a glycidyl ether group represented by formula (4) can be obtained, and a cured product can be obtained as the curing reaction proceeds. The maleimide with a glycidyl ether group that can be used at this time is the same as that described above.

[0502] The epoxy resin composition of this embodiment and the cured product made from the epoxy resin composition have adhesiveness, flexibility and deconstructability, and can be used for the following applications.

[0503] The cured resin of this embodiment can be laminated with a substrate to form a laminate. As the substrate for the laminate, any suitable inorganic material such as metal or glass, or an organic material such as plastic or wood, can be used depending on the application. The shape of the laminate can be flat, sheet-like, or a three-dimensional structure, or even a three-dimensional shape. It can also be any shape corresponding to the purpose, such as a shape with curvature on the entire surface or a portion thereof. Furthermore, there are no limitations on the hardness or thickness of the substrate. Additionally, a multilayer laminate can be formed by laminating a first substrate, a layer formed from the cured epoxy resin composition of this embodiment, and a second substrate in that order. The epoxy resin composition of this embodiment has excellent adhesive properties, and therefore can be suitable as an adhesive for bonding the first substrate and the second substrate. Alternatively, the cured resin of this embodiment can be used as a substrate, and the cured product of this embodiment can be further laminated.

[0504] Furthermore, the cured resin of this embodiment can alleviate stress, making it particularly suitable for bonding different types of materials. For example, even in laminates of different types of materials, such as a metal and / or metal oxide substrate and a plastic layer as the second substrate, the adhesive strength can be maintained by the stress-relieving ability of the cured resin of this embodiment.

[0505] In a laminate formed by stacking the cured product of this embodiment with a substrate, the layer containing the cured product can be formed by directly coating and molding the substrate, or by stacking pre-formed layers. In the case of direct coating, the coating method is not particularly limited, and examples include: spraying, spin coating, dipping, roller coating, scraper coating, doctor blade coating, curtain coating, slot coating, screen printing, inkjet printing, etc. In the case of direct molding, examples include: in-mold molding, insert molding, vacuum molding, extrusion lamination molding, compression molding, etc. When stacking pre-formed compositions, uncured or semi-cured composition layers can be stacked and then cured, or a layer containing a cured product formed by fully curing the composition can be stacked on the substrate. Furthermore, the cured product of this embodiment can be laminated by coating a precursor that can become a substrate and then curing it, or the precursor that can become a substrate or the composition of this embodiment can be bonded in an uncured or semi-cured state and then cured. There are no particular limitations on the precursors that can be used as substrates; various epoxy resin compositions are examples.

[0506] The cured product obtained using the epoxy resin composition of this embodiment exhibits particularly high adhesion to metals and / or metal oxides, and therefore can be used particularly well as a primer for metals. Examples of metals include copper, aluminum, gold, silver, iron, platinum, chromium, nickel, tin, titanium, zinc, various alloys, and materials composed of these metals. Examples of metal oxides include individual oxides and / or composite oxides of these metals. In particular, it exhibits excellent adhesion to iron, copper, and aluminum, and therefore can be used well as an adhesive for iron, copper, and aluminum.

[0507] The epoxy resin composition of this embodiment is suitable for use as an adhesive for structural components in the automotive, tram, civil engineering, electronic equipment, aircraft, and aerospace industries. For example, even when used for bonding different raw materials such as metals and non-metals, this adhesive maintains high adhesion regardless of temperature variations and is less prone to peeling. In addition to its structural component applications, this adhesive can also be used for general office applications, medical applications, carbon fiber applications, battery units or modules or housings, and can also be used as an adhesive for bonding optical components, bonding optical discs, mounting printed circuit boards, die bonding, semiconductor adhesives such as underfills, BGA reinforcement underfills, and mounting adhesives for anisotropic conductive films and anisotropic conductive pastes.

[0508] In this embodiment, when the epoxy resin composition has a fibrous matrix and the fibrous matrix is ​​a reinforcing fiber, the epoxy resin composition containing the fibrous matrix can be used as a fiber-reinforcing resin. Regarding the method of containing the fibrous matrix in the composition, there are no particular limitations as long as it does not impair the effects of the present invention. Examples include methods such as compounding, coating, impregnation, injection, and pressing to combine the fibrous matrix with the composition. The appropriate method can be selected based on the morphology of the fibers and the intended use of the fiber-reinforcing resin.

[0509] There are no particular limitations on the method for molding fiber-reinforced resin. For sheet-like products, extrusion molding is generally used. Alternatively, planar pressing can also be used. Other methods include extrusion molding, blow molding, compression molding, vacuum forming, and injection molding. For film-like products, in addition to melt extrusion, solution casting can be used. Examples of melt molding methods include blown film forming, casting, extrusion lamination, calendering, sheet forming, fiber forming, blow molding, injection molding, rotational molding, and coating molding. Furthermore, for resins cured with active energy rays, various curing methods utilizing active energy rays can be used to manufacture cured products. In particular, when thermosetting resins are the main component of the matrix resin, methods such as prepreg molding of the molding material and pressing or pressurizing and heating in an autoclave can be used. In addition, examples include: Resin Transfer Molding (RTM), Vacuum Assist Resin Transfer Molding (VaRTM), Lamination Molding, and Hand Lay-up Molding.

[0510] The epoxy resin composition of this embodiment has excellent adhesion, flexibility, and disassembly properties when used in its cured form, making it suitable for use in large housings, engine housings, internal casting materials, gears, pulleys, and other molding materials. These can be cured resin products alone or cured products reinforced with fibers such as glass chips.

[0511] Fiber-reinforced resins can be formed in an uncured or semi-cured state known as prepreg. Alternatively, the product can be circulated in the prepreg state and then undergo final curing to form a cured product. In the case of forming a laminate, by forming the prepreg and then layering other layers before final curing, a tightly bonded laminate can be formed, which is therefore preferred. The mass ratio of the composition used in this process to the fibrous matrix is ​​not particularly limited, but it is generally preferred to prepare the prepreg with a resin content of 20-60% by mass.

[0512] The cured product of this embodiment has excellent adhesion, flexibility, and disassembly properties, making it suitable for use as a heat-resistant material and electronic material. In particular, it is suitable for use in semiconductor sealing materials, circuit boards, build-up films, build-up substrates, adhesives, and photoresist materials. Additionally, it is suitable as a matrix resin for fiber-reinforced resins, and is especially suitable as a high-heat-resistant prepreg. The resulting heat-resistant components and electronic components can be suitable for a variety of applications, including, but not limited to, industrial machinery parts, general machinery parts, automotive / railway / vehicle parts, aerospace-related parts, electronic / electrical parts, building materials, container / packaging components, consumer goods, sports / leisure products, and wind power generation housing components.

[0513] The adhesive, due to its excellent flexibility after curing, can be suitable for use as an adhesive for structural components in the automotive, tram, civil engineering, electronic equipment, aircraft, and aerospace industries. For example, even when bonding different raw materials such as metals and non-metals, the adhesive of this embodiment can maintain high adhesion regardless of temperature changes and is less prone to peeling. Furthermore, in addition to its use in structural components, the adhesive of this embodiment can also be used as an adhesive for general office applications, medical applications, carbon fiber applications, battery units or modules or housings, etc. Examples include adhesives for bonding optical components, adhesives for bonding optical discs, adhesives for mounting printed circuit boards, chip bonding adhesives, semiconductor adhesives such as underfills, underfills for BGA reinforcement, and adhesives for mounting anisotropic conductive films and anisotropic conductive pastes.

[0514] Alternatively, an easy-to-disassemble adhesive material that exhibits the excellent disassembly properties of the cured product of this embodiment and includes the epoxy resin composition of this embodiment can be used. The aforementioned easy-to-disassemble adhesive material is preferably the epoxy resin composition of this embodiment. A disassembly method using the easy-to-disassemble adhesive material of this embodiment includes, for example: a bonding step, in which the aforementioned easy-to-disassemble adhesive material is attached to the surface of the adherend and bonded to the adherend; a curing step, in which the aforementioned easy-to-disassemble adhesive material is cured to obtain a cured product; a heat treatment step, in which the cured product is subjected to heat treatment to thermally dissociate the reversible bonds contained in the aforementioned general formula (4) derived from the aforementioned compound (C) containing glycidyl ether groups and to expand the aforementioned thermally expandable particles (D); and a disassembly step, in which the adherend and the cured product are separated.

[0515] In addition, the disassembly method using the easily disassembleable adhesive material of this embodiment includes, for example: a bonding step, in which the aforementioned easily disassembleable adhesive material is attached to the surface of the adherend and bonded to the adherend; a curing step, in which the aforementioned easily disassembleable adhesive material is cured to obtain a cured product; a heat treatment step, in which the cured product is subjected to heat treatment to thermally dissociate the reversible bonds contained in the aforementioned general formula (4) derived from the aforementioned compound (C) containing glycidyl ether group and to expand the aforementioned thermally expandable particles (D); a cooling step, in which the heat-treated cured product is cooled to room temperature; and a disassembly step, in which the adherend and the cured product are disassembled.

[0516] The following are examples of representative products.

[0517] 1. Semiconductor sealing materials

[0518] As a method for obtaining a semiconductor sealing material from the resin composition of this embodiment, one example is to use an extruder, kneader, roller, etc., to fully melt and mix the aforementioned resin composition, curing accelerator, and inorganic filler, etc., until homogeneous. In this case, fused silica is typically used as the inorganic filler. However, when used as a high thermal conductivity semiconductor sealing material for power transistors and power ICs, highly filled materials such as crystalline silica, alumina, or silicon nitride, or fused silica, crystalline silica, alumina, or silicon nitride, which have higher thermal conductivity than fused silica, can be used. Regarding the filling rate, it is preferable to use an inorganic filler in the range of 30 to 95% by mass relative to 100 parts by mass of the epoxy resin composition. More preferably, it is 70 parts by mass or more, and even more preferably 80 parts by mass or more, to improve flame retardancy, moisture resistance, resistance to weld cracking, and reduce the coefficient of linear expansion.

[0519] 2. Semiconductor devices

[0520] As a semiconductor encapsulation molding method for obtaining a semiconductor device from the epoxy resin composition of this embodiment, examples include: casting the above-mentioned semiconductor sealing material, or molding it using a transfer molding machine, injection molding machine, etc., and then heating it at 50~250°C for 2~10 hours.

[0521] 3. Printed Circuit Board

[0522] As a method for obtaining a printed circuit board from the composition of this embodiment, an example is a method of laminating the above-mentioned prepreg by conventional methods, appropriately overlapping copper foils, and heating and pressing at 170 to 300°C for 10 minutes to 3 hours under a pressure of 1 to 10 MPa.

[0523] 4. Flexible substrate

[0524] As a method for manufacturing a flexible substrate from the crosslinked resin composition of this embodiment, a method comprising the following three steps can be cited. The first step is to coat an electrical insulating film with a crosslinked resin composition containing resin components, organic solvents, etc., using a coating machine such as a reverse roller coater or a comma coater; the second step is to heat the electrical insulating film coated with the crosslinked resin composition at 60 to 170°C for 1 to 15 minutes using a heating machine, so that the solvent evaporates from the electrical insulating film and the crosslinked resin composition is B-stage; the third step is to hot-press a metal foil (preferably 2 to 200 N / cm, and preferably 40 to 200°C) onto an adhesive using a heating roller or the like. It should be noted that if sufficient bonding performance can be obtained through the above three processes, it is acceptable to stop here. However, if complete bonding performance is required, it is preferable to perform post-curing at 100-200°C for 1-24 hours. The thickness of the finally cured resin composition layer is preferably in the range of 5-100 μm.

[0525] 5. Addition layer substrate

[0526] The method for obtaining an augmentation substrate from the composition of this embodiment can be exemplified by the following steps. First, using a spraying method, curtain coating method, or similar method, the above-mentioned composition, appropriately formulated with rubber, filler, etc., is applied to a circuit board on which circuits are formed, and then cured (step 1). Then, after opening holes such as predetermined through-holes as needed, the surface is treated with a roughening agent, washed with hot water to form an uneven surface, and then plated with metal such as copper (step 2). This operation is repeated sequentially as needed to alternately add layers to form a resin insulating layer and a conductor layer with a predetermined circuit pattern (step 3). It should be noted that the opening of the through-holes is performed after the outermost resin insulating layer is formed. In addition, the augmentation substrate of this embodiment can also be manufactured by heating and pressing a resin-coated copper foil, which is formed by semi-curing the resin composition on a copper foil, onto a wiring board on which circuits are formed at 170~300°C to form a roughened surface, thus eliminating the plating process.

[0527] 6. Extension membrane

[0528] As a method for obtaining a laminated film from the composition of this embodiment, it can be manufactured by coating the above composition onto the surface of a support film (Y) serving as a substrate, and then drying it with an organic solvent by heating or blowing hot air to form a layer (X) of the composition.

[0529] As the organic solvent used herein, ketones such as acetone, methyl ethyl ketone, and cyclohexanone are preferred, as are ethyl acetate, butyl acetate, cellolytic acetate, propylene glycol monomethyl ether acetate, carbitol acetate, cellolytic agents, carbitols such as butyl carbitol, aromatic hydrocarbons such as toluene and xylene, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. In addition, it is preferred to use it at a ratio of 30 to 60% by mass of non-volatile components.

[0530] The thickness of the formed layer (X) is typically greater than or equal to the thickness of the conductor layer. The conductor layer of the circuit board typically has a thickness in the range of 5 to 70 μm; therefore, the resin composition layer preferably has a thickness of 10 to 100 μm. It should be noted that the layer (X) of the composition described above in this embodiment can also be protected by the protective film described later. By using a protective film, dirt and other contaminants, as well as damage, can be prevented from adhering to the surface of the resin composition layer.

[0531] Examples of the aforementioned support and protective films include: polyolefins such as polyethylene, polypropylene, and polyvinyl chloride; polyesters such as polyethylene terephthalate (hereinafter sometimes referred to as "PET") and polyethylene naphthalate; polycarbonate; polyimide; and metal foils such as release paper, copper foil, and aluminum foil. It should be noted that, in addition to matte treatment and corona treatment, a release treatment can also be applied to the support and protective films. The thickness of the support film is not particularly limited, typically ranging from 10 to 150 μm, preferably in the range of 25 to 50 μm. Furthermore, the thickness of the protective film is preferably set to 1 to 40 μm.

[0532] The aforementioned support film (Y) is peeled off after being laminated onto the circuit board or after forming an insulating layer through heat curing. If the support film (Y) is peeled off after the epoxy resin composition layer constituting the laminate has been heat-cured, it is possible to prevent the adhesion of dirt or other contaminants during the curing process. In the case of peeling off after curing, the support film is typically subjected to a pre-molding treatment.

[0533] The build-up film obtained as described above can be used to manufacture multilayer printed circuit boards. For example, when the layers (X) are protected by a protective film, after peeling them off, the layers (X) are laminated onto one or both sides of the circuit board in direct contact with the circuit board, for example, by vacuum lamination. The lamination method can be intermittent or continuous using rollers. Additionally, if necessary, the build-up film and the circuit board can be heated (preheated) before lamination. Regarding the lamination conditions, it is preferable to set the lamination temperature to 70~140°C and the lamination pressure to 1~11 kgf / cm². 2 (9.8×10 4 ~107.9×10 4 N / m 2It is preferable to perform lamination under reduced pressure, with the air pressure below 20 mmHg (26.7 hPa).

[0534] 7. Conductive paste

[0535] As a method for obtaining conductive paste from the epoxy resin composition of this embodiment, a method of dispersing conductive particles in the composition can be cited as an example. The conductive paste described above can be made into a circuit connection paste resin composition or an anisotropic conductive adhesive, depending on the type of conductive particles used.

[0536] Example

[0537] Next, the present invention will be specifically described through examples and comparative examples. Unless otherwise specified, "parts" and "%" are mass measurements. The present invention is not limited thereto.

[0538] 1 H and 13 C-NMR, FD-MS, and GPC were determined under the following conditions.

[0539] 1 H-NMR: "JNM-ECA600" manufactured by JEOL RESONANCE

[0540] Magnetic field strength: 600 MHz

[0541] Total number of times: 32

[0542] Solvent: DMSO-d6

[0543] Sample concentration: 30% by mass

[0544] 13 C-NMR: JEOL RESONANCE "JNM-ECA600"

[0545] Magnetic field strength: 150 MHz

[0546] Total number of times: 320

[0547] Solvent: DMSO-d6

[0548] Sample concentration: 30% by mass

[0549] FD-MS: JMS-T100GC AccuTOF manufactured by Nippon Electronics Co., Ltd.

[0550] Measurement range: m / z = 50.00~2000.00

[0551] Rate of change: 25.6 mA / min

[0552] Final current value: 40mA

[0553] Cathode voltage: -10kV

[0554] GPC: "HLC-8320GPC" manufactured by Tosoh Corporation

[0555] Column: "TSK-GEL G2000HXL" + "TSK-GEL G3000HXL" + "TSK-GELG4000HXL" manufactured by Tosoh Corporation

[0556] Detector: RI (Differential Refractometer)

[0557] Measurement conditions: 40℃

[0558] Mobile phase: Tetrahydrofuran

[0559] Flow rate: 1 ml / min

[0560] Standards: Tosoh Corporation's "PStQuick A", "PStQuick B", "PStQuick E", and "PStQuick F"

[0561] The epoxy equivalent of the synthesized epoxy resin was determined according to JIS K7236, and the epoxy equivalent (g / eq) was calculated.

[0562] As a method for calculating the number of repeating units, examples can be shown of calculations based on the analytical results of various appropriate instruments such as GPC molecular weight determination, FD-MS, and NMR.

[0563] Synthesis example 1

[0564] In a flask equipped with a thermometer, cooling tube, and stirrer, 420 g (2.0 equivalents) of 1,12-dodecanediol diglycidyl ether (manufactured by Yokkaichi Synthetic Co., Ltd.: epoxy equivalent 210 g / eq) and 240 g (2.1 equivalents) of bisphenol A (hydroxyl equivalent 114 g / eq) were added. After heating to 140°C over 30 minutes, 6.6 g of a 20% sodium hydroxide aqueous solution was added. The temperature was then increased to 150°C over 30 minutes, and the reaction was carried out at 150°C for 16 hours. Afterward, a neutralization amount of sodium phosphate was added to obtain 646 g of the hydroxyl compound (Ph-1). This hydroxyl compound (Ph-1) showed a peak at M+=771 in mass spectrometry, corresponding to the theoretical structure with m=1 in the following structural formula (Ph-1), thus confirming the presence of a hydroxyl compound as the target. The hydroxyl equivalent of this hydroxyl compound (Ph-1), calculated by GPC, is 2053 g / eq, and the average value of the repeating unit m is 6.9.

[0565] [Chemistry 94]

[0566]

[0567] Synthesis example 2

[0568] The 420 g (2.0 equivalent) of 1,12-dodecanediol diglycidyl ether (epoxide equivalent 210 g / eq) in Synthesis Example 1 was replaced with 472 g (2.0 equivalent) of 1,15-pentadecanediol diglycidyl ether (epoxide equivalent 236 g / eq), but the reaction was carried out in the same manner as in Synthesis Example 1, yielding 697 g of the hydroxyl compound (Ph-2). This hydroxyl compound (Ph-2) showed a peak at M+=813 in mass spectrometry, corresponding to the theoretical structure with m=1 in the following structural formula (Ph-2), thus confirming the presence of a hydroxyl compound as the target. The hydroxyl equivalent of this hydroxyl compound (Ph-2) calculated by GPC was 2226 g / eq, and the average value of the repeating unit m was 6.8.

[0569] [Chemistry 95]

[0570]

[0571] Synthesis example 3

[0572] The 420 g (2.0 equivalent) of 1,12-dodecanediol diglycidyl ether (epoxy equivalent 210 g / eq) in Synthesis Example 1 was replaced with 380 g (2.0 equivalent) of 1,9-nonanediol diglycidyl ether (epoxy equivalent 190 g / eq), but the reaction was carried out in the same manner as in Synthesis Example 1, yielding 607 g of the hydroxyl compound (Ph-3). This hydroxyl compound (Ph-3) showed a peak at M+=729 in mass spectrometry, corresponding to the theoretical structure with m=1 in the following structural formula (Ph-3), thus confirming the presence of a hydroxyl compound as the target. The hydroxyl equivalent of this hydroxyl compound (Ph-3) calculated by GPC was 1989 g / eq, and the average value of the repeating unit m was 7.2.

[0573] [Chemistry 96]

[0574]

[0575] Synthesis example 4

[0576] The 420 g (2.0 equivalents) of 1,12-dodecanediol diglycidyl ether (manufactured by Yokkaichi Synthesis Co., Ltd.: epoxy equivalent 210 g / eq) and 240 g (2.1 equivalents) of bisphenol A (hydroxyl equivalent 114 g / eq) in Synthesis Example 1 were replaced with 962 g (2.0 equivalents) of polypropylene glycol diglycidyl ether (manufactured by Nagase ChemteX "DENACOL EX-931": epoxy equivalent 481 g / eq) and 274 g (2.4 equivalents) of bisphenol A (hydroxyl equivalent 114 g / eq). Otherwise, the reaction was carried out in the same manner as in Synthesis Example 1 to obtain 1211 g of hydroxy compound (Ph-4). This hydroxyl compound (Ph-4) showed a peak at M+=1226 in mass spectrometry, corresponding to the theoretical structure of the following structural formula (Ph-4) with m=1 and n2=11, thus confirming the presence of a hydroxyl group as the target compound. The hydroxyl equivalent of this hydroxyl compound (Ph-4) calculated by GPC is 1582 g / eq, and the average value of the repeating unit m is 3.3.

[0577] [Chemistry 97]

[0578]

[0579] Synthesis example 5

[0580] The 420 g (2.0 equivalents) of 1,12-dodecanediol diglycidyl ether (manufactured by Yokkaichi Synthesis Co., Ltd.: epoxy equivalent 210 g / eq) and 240 g (2.1 equivalents) of bisphenol A (hydroxyl equivalent 114 g / eq) in Synthesis Example 1 were replaced with 890 g (2.0 equivalents) of polytetramethylene glycol diglycidyl ether (manufactured by Nagase ChemteX "DENACOL EX-991L": epoxy equivalent 445 g / eq) and 274 g (2.4 equivalents) of bisphenol A (hydroxyl equivalent 114 g / eq). Otherwise, the reaction was carried out in the same manner as in Synthesis Example 1 to obtain 1140 g of hydroxy compound (Ph-5). This hydroxyl compound (Ph-5) showed a peak at M+=1380 in mass spectrometry, corresponding to the theoretical structure of the following structural formula (Ph-5) with m=1 and n2=11, thus confirming the presence of a hydroxyl group as the target compound. The hydroxyl equivalent of this hydroxyl compound (Ph-5) calculated by GPC is 2520 g / eq, and the average value of the repeating unit m is 5.1.

[0581] [Chem. 98]

[0582]

[0583] Synthesis example 6

[0584] The 420 g (2.0 mol) of 1,12-dodecanediol diglycidyl ether (manufactured by Yokkaichi Synthetic Co., Ltd.: epoxy equivalent 210 g / eq) and 240 g (2.1 mol) of bisphenol A (hydroxyl equivalent 114 g / eq) in Synthesis Example 1 were replaced with 126.2 g (0.39 mol) of 1,6-hexanediol diglycidyl ether (Sakamoto Pharmaceutical Co., Ltd. "SR-16H": epoxy equivalent 160 g / eq), 78.1 g (0.08 mol) of polypropylene glycol diglycidyl ether (manufactured by Nagase ChemteX "DENACOL EX-931": epoxy equivalent 481 g / eq), and 114.6 g (0.50 mol) of bisphenol A (hydroxyl equivalent 114 g / eq). Otherwise, the reaction was carried out in the same manner as in Synthesis Example 1 to obtain 317 g of hydroxy compound (Ph-6). This hydroxyl compound (Ph-6) showed a peak at M+=1684 in mass spectrometry, corresponding to the theoretical structure of the following structural formula (Ph-6) with m1=1, m2=1, n2=11, thus confirming the presence of a hydroxyl group as the target compound. The hydroxyl equivalent of this hydroxyl compound (Ph-6) calculated by GPC is 1597 g / eq.

[0585] [Chemistry 99]

[0586]

[0587] Synthesis Example 7

[0588] The 420 g (2.0 mol) of 1,12-dodecanediol diglycidyl ether (manufactured by Yokkaichi Synthetic Co., Ltd.: epoxy equivalent 210 g / eq) and 240 g (2.1 mol) of bisphenol A (hydroxyl equivalent 114 g / eq) in Synthesis Example 1 were replaced with 136 g (0.43 mol) of 1,6-hexanediol diglycidyl ether (Sakamoto Pharmaceutical Co., Ltd. "SR-16H": epoxy equivalent 160 g / eq), 66 g (0.07 mol) of polytetramethylenediol diglycidyl ether (manufactured by Nagase ChemteX "DENACOL EX-991L": epoxy equivalent 445 g / eq) and 119.7 g (0.53 mol) of bisphenol A (hydroxyl equivalent 114 g / eq). Otherwise, the reaction was carried out in the same manner as in Synthesis Example 1 to obtain 318 g of hydroxy compound (Ph-7). This hydroxyl compound (Ph-7) showed a peak at M+=1839 in mass spectrometry, corresponding to the theoretical structure of the following structural formula (Ph-7) with m1=1, m2=1, n2=11, thus confirming the presence of a hydroxyl group as the target compound. The hydroxyl equivalent of this hydroxyl compound (Ph-7) calculated by GPC is 1896 g / eq.

[0589] [Chemistry 100]

[0590]

[0591] Synthesis example 8

[0592] In a flask equipped with a thermometer, dropping funnel, cooling tube, and stirrer, 205.3 g of the hydroxyl compound (Ph-1) obtained in Synthesis Example 1, 647.5 g (7.0 mol) of epichlorohydrin, and 150 g of n-butanol were added and dissolved while purging with nitrogen. The temperature was then raised to 65°C, and the pressure was reduced to azeotropic pressure. 10.6 g (0.13 mol) of a 49% sodium hydroxide aqueous solution was added dropwise over 5 hours. The mixture was then stirred continuously under the same conditions for 0.5 hours. During this time, the distillate from the azeotropic distillation was separated using a Dean-Stark trap, removing the aqueous layer and returning the oil layer to the reaction system while the reaction continued. Unreacted epichlorohydrin was then distilled off by vacuum distillation. The resulting crude epoxy resin was dissolved in 200 g of methyl isobutyl ketone and 100 g of n-butanol. Then, 15.0 g of a 10% sodium hydroxide aqueous solution was added to the solution, and the reaction was carried out at 80°C for 2 hours. The solution was then washed three times with 100 g of water until the pH of the washing solution became neutral. Next, the system was dehydrated by azeotropic distillation, and after precision filtration, the solvent was removed under reduced pressure to obtain 235 g of epoxy resin (Ep-1). The epoxy equivalent of the obtained epoxy resin (Ep-1) was 2320 g / eq. The epoxy resin showed a peak at M+=883 in mass spectrometry, corresponding to the theoretical structure of the following structural formula (Ep-1) with m=1, q=1, p1=0, p2=0, thus confirming the presence of the target epoxy resin (Ep-1).

[0593] [Chemistry 101]

[0594]

[0595] Synthesis example 9

[0596] The 205.3 g of hydroxyl compound (Ph-1) in Synthesis Example 8 was replaced with 222.6 g of hydroxyl compound (Ph-2), and the reaction was carried out in the same manner as in Synthesis Example 8 to obtain 251 g of epoxy resin (Ep-2). The epoxy equivalent of the obtained epoxy resin (Ep-2) was 2510 g / eq. The epoxy resin showed a peak at M+=925 in mass spectrometry, which corresponds to the theoretical structure of the following structural formula (Ep-2) with m=1, p1=0, p2=0, q=1, thus confirming that the epoxy resin (Ep-2) contains the target compound.

[0597] [Chemistry 102]

[0598]

[0599] Synthesis example 10

[0600] The 205.3 g of hydroxyl compound (Ph-1) in Synthesis Example 8 was replaced with 198.9 g of hydroxyl compound (Ph-3), and the reaction was carried out in the same manner as in Synthesis Example 8 to obtain 229 g of epoxy resin (Ep-3). The epoxy equivalent of the obtained epoxy resin (Ep-3) was 2250 g / eq. The epoxy resin showed a peak at M+=841 in mass spectrometry, which corresponds to the theoretical structure of the following structural formula (Ep-3) with m=1, p1=0, p2=0, q=1, thus confirming that the epoxy resin (Ep-3) contains the target compound.

[0601] [Chemistry 103]

[0602]

[0603] Synthesis example 11

[0604] The 205.3 g of hydroxyl compound (Ph-1) in Synthesis Example 8 was replaced with 158.2 g of hydroxyl compound (Ph-4), and the reaction was carried out in the same manner as in Synthesis Example 8 to obtain 193 g of epoxy resin (Ep-4). The epoxy equivalent of the obtained epoxy resin (Ep-4) was 1802 g / eq. The epoxy resin showed a peak at M+=1336 in mass spectrometry, which corresponds to the theoretical structure of the following structural formula (Ep-4) with m=1, n2=11, p1=0, p2=0, q=1, thus confirming that the epoxy resin (Ep-4) contains the target compound.

[0605] [Chemistry 104]

[0606]

[0607] Synthesis example 12

[0608] The 205.3 g of hydroxyl compound (Ph-1) in Synthesis Example 8 was replaced with 252.0 g of hydroxyl compound (Ph-5), and the reaction was carried out in the same manner as in Synthesis Example 8 to obtain 277 g of epoxy resin (Ep-5). The epoxy equivalent of the obtained epoxy resin (Ep-5) was 2834 g / eq. The epoxy resin showed a peak at M+=1492 in mass spectrometry, which corresponds to the theoretical structure of the following structural formula (Ep-5) with m=1, n2=11, p1=0, p2=0, q=1, thus confirming that the epoxy resin (Ep-5) contains the target compound.

[0609] [Chemistry 105]

[0610]

[0611] Synthesis example 13

[0612] The 205.3 g of hydroxyl compound (Ph-1) in Synthesis Example 8 was replaced with 198.4 g of hydroxyl compound (Ph-6), and the reaction was carried out in the same manner as in Synthesis Example 8 to obtain 229 g of epoxy resin (Ep-6). The epoxy equivalent of the obtained epoxy resin (Ep-6) was 2244 g / eq. The epoxy resin showed a peak at M+=1796 in mass spectrometry, which corresponds to the theoretical structure of the following structural formula (Ep-6) with m1=1, m2=2, n2=11, p1=0, p2=0, q=1, thus confirming that the epoxy resin (Ep-6) contains the target compound.

[0613] [Chemistry 106]

[0614]

[0615] Synthesis example 14

[0616] The 205.3 g of hydroxyl compound (Ph-1) in Synthesis Example 8 was replaced with 191.4 g of hydroxyl compound (Ph-7), and the reaction was carried out in the same manner as in Synthesis Example 8 to obtain 223 g of epoxy resin (Ep-7). The epoxy equivalent of the obtained epoxy resin (Ep-7) was 2167 g / eq. The epoxy resin showed a peak at M+=1951 in mass spectrometry, which corresponds to the theoretical structure of the following structural formula (Ep-7) with m1=1, m2=2, n2=11, p1=0, p2=0, q=1, thus confirming that the epoxy resin (Ep-7) contains the target compound.

[0617] [Chemistry 107]

[0618]

[0619] Synthesis Example 15

[0620] In a flask equipped with a thermometer and a stirrer, 117 g (0.5 mol) of resorcinol diglycidyl ether (Nagase ChemteX "DENACOL EX-201": epoxy equivalent 117 g / eq) and 189 g (1.0 mol) of 4-hydroxyphenyl maleimide were added. The mixture was heated to 140 °C over 30 minutes, followed by the addition of 15 g of a 4% sodium hydroxide aqueous solution. The temperature was then increased to 150 °C over 30 minutes, and the reaction was carried out at 150 °C for 15 hours. Finally, a neutralization amount of sodium phosphate was added to yield 296 g of maleimide compound (M-1).

[0621] [Chemistry 108]

[0622]

[0623] Synthesis example 16

[0624] 101 g (0.5 mol) of 1,4-butanediol diglycidyl ether and 189 g (1.0 mol) of 4-hydroxyphenylmaleimide were added to a flask equipped with a thermometer and a stirrer. The mixture was heated to 140 °C over 30 minutes, followed by the addition of 15 g of a 4% sodium hydroxide aqueous solution. The temperature was then increased to 150 °C over 30 minutes, and the reaction was carried out at 150 °C for 20 hours. Finally, a neutralization amount of sodium phosphate was added to yield 285 g of maleimide compound (M-2).

[0625] [Chemistry 109]

[0626]

[0627] Synthesis Example 17

[0628] In a flask equipped with a thermometer and a stirrer, 135 g (0.5 mol) of 1,6-hexanediol diglycidyl ether (Nagase ChemteX "DENACOL EX-212L": epoxy equivalent 135 g / eq) and 189 g (1.0 mol) of 4-hydroxyphenyl maleimide were added. The mixture was heated to 140 °C over 30 minutes, followed by the addition of 15 g of a 4% sodium hydroxide aqueous solution. The temperature was then increased to 150 °C over 30 minutes, and the reaction was carried out at 150 °C for 20 hours. Finally, a neutralization amount of sodium phosphate was added to yield 314 g of maleimide compound (M-3).

[0629] [Chemical 110]

[0630]

[0631] Synthesis Example 18

[0632] In a flask equipped with a thermometer, cooling tube, and stirrer, 101 g (0.5 mol) of 1,3-dibromopropane, 189 g (1.0 mol) of 4-hydroxyphenylmaleimide, 1430 g of dehydrated acetone, and 552 g of micronized potassium carbonate were added. After purging with nitrogen, the mixture was reacted at 55 °C for 24 hours. The mixture was cooled to room temperature and filtered. 2100 g of toluene was added, and the insoluble matter was removed by filtration. 2100 g of water was added, and the mixture was separated three times. After dehydrating the organic layer with sodium sulfate, the toluene was removed by vacuum distillation through an evaporator to obtain 202 g of maleimide compound (M-4).

[0633] [Chemistry 111]

[0634]

[0635] Synthesis example 19

[0636] In a flask equipped with a thermometer, cooling tube, and stirrer, 164 g (0.5 mol) of 1,12-dibromododecane, 189 g (1.0 mol) of 4-hydroxyphenylmaleimide, 1430 g of dehydrated acetone, and 552 g of micronized potassium carbonate were added. After purging with nitrogen, the mixture was reacted at 55 °C for 24 hours. The mixture was cooled to room temperature and filtered. 2100 g of toluene was added, and the insoluble matter was removed by filtration. 2100 g of water was added, and the mixture was separated three times. After dehydrating the organic layer with sodium sulfate, the toluene was removed by vacuum distillation through an evaporator to obtain 231 g of maleimide compound (M-5).

[0637] [Chemistry 112]

[0638]

[0639] Synthesis example 20

[0640] In a flask equipped with a thermometer, stirrer, and cooling tube, 300.3 g of the maleimide compound (M-1) obtained in Synthesis Example 15, 154.2 g of furfuryl glycidyl ether (prepared by Sigma-Aldrich), and 400 g of tetrahydrofuran were added. After nitrogen purging, the mixture was reacted at 60 °C for 12 hours. Subsequently, the tetrahydrofuran was removed by vacuum distillation to give 432 g of a compound containing a glycidyl ether group (D-1). This compound containing a glycidyl ether group showed a peak at M+=909 in mass spectrometry, thus confirming the presence of the target compound (D-1). Furthermore, the epoxy equivalent was 478 g / eq.

[0641] [Chemistry 113]

[0642]

[0643] Synthesis Example 21

[0644] The 300.3 g of maleimide compound (M-1) in Synthesis Example 20 was replaced with 290.3 g of maleimide compound (M-2), but the reaction was otherwise carried out in the same manner as in Synthesis Example 20, yielding 422 g of compound (D-2) containing a glycidyl ether group. This compound containing a glycidyl ether group showed a peak of M+=889 in mass spectrometry, thus confirming the presence of the target compound (D-2) containing a glycidyl ether group. Furthermore, the epoxy equivalent was 468 g / eq.

[0645] [Chemistry 114]

[0646]

[0647] Synthesis example 22

[0648] The 300.3 g of maleimide compound (M-1) in Synthesis Example 20 was replaced with 304.3 g of maleimide compound (M-3), but the reaction was carried out in the same manner as in Synthesis Example 20, yielding 436 g of compound containing glycidyl ether groups (D-3). This compound containing glycidyl ether groups showed a peak at M+=917 in mass spectrometry, thus confirming the presence of the target compound (D-3) containing glycidyl ether groups. Furthermore, the epoxy equivalent was 483 g / eq.

[0649] [Chemistry 115]

[0650]

[0651] Synthesis example 23

[0652] The 300.3 g of maleimide compound (M-1) in Synthesis Example 20 was replaced with 209.2 g of maleimide compound (M-4), but the reaction was carried out in the same manner as in Synthesis Example 20, yielding 345 g of compound (D-4) containing a glycidyl ether group. This compound containing a glycidyl ether group showed a peak at M+=727 in mass spectrometry, thus confirming the presence of the target compound (D-4) containing a glycidyl ether group. Furthermore, the epoxy equivalent was 383 g / eq.

[0653] [Chemistry 116]

[0654]

[0655] Synthesis example 24

[0656] The 300.3 g of maleimide compound (M-1) in Synthesis Example 20 was replaced with 272.3 g of maleimide compound (M-5), but the reaction was carried out in the same manner as in Synthesis Example 20, yielding 405 g of compound containing a glycidyl ether group (D-5). This compound containing a glycidyl ether group showed a peak at M+=853 in mass spectrometry, thus confirming the presence of the target compound (D-5). Furthermore, the epoxy equivalent was 431 g / eq.

[0657] [Chemistry 117]

[0658]

[0659] Preparation of compositions and cured products of Examples 1 to 30 and Comparative Examples 1 to 6

[0660] According to the formulations in Tables 1 and 2 (the numbers in the tables are based on mass), each compound was uniformly mixed using a mixer (THINKY Co., Ltd. "Awatori Rentaro ARV-200") to obtain a curable resin composition. This curable resin composition was then sandwiched between an aluminum mirror panel (Engineering Test Service Co., Ltd. "JIS H4000 A1050P") using silicone tubes as spacers, and cured under predetermined conditions to obtain a cured product with a thickness of 0.7 mm.

[0661] <Elongation at break>

[0662] The cured material was punched into dumbbell shapes using a punching blade (JIS K 7161-2-1BA) and used as test pieces. Tensile tests were performed on these test pieces using a tensile testing machine (Autograph AG-IS, manufactured by Shimadzu Corporation) according to JIS K 7162-2, and the elongation at the breaking point was evaluated by measuring the ambient temperature of 23°C (test speed: 2 mm / min).

[0663] <Evaluation of Adhesion and Disassembly>

[0664] According to the formulations in Tables 1 and 2 (the numbers in the tables are based on mass), each compound was uniformly mixed using a mixer (THINKY Awatori Rentaro ARV-200, manufactured by THINKY Co., Ltd.) to obtain a curable resin composition. This resin composition was applied to one of two cold-rolled steel sheets (SPCC-SD, manufactured by TP Giken Co., Ltd., 1.0 mm × 25 mm × 100 mm), with glass beads (J-80, manufactured by Potters-Ballotini Co., Ltd.) added as spacers, and the other SPCC-SD sheet was then bonded together (bonding area: 25 mm × 12.5 mm). The sheets were then heated and cured according to the temperatures specified in Tables 1 and 2 to obtain shear test specimens. Tensile shear tests were performed using these specimens to evaluate the adhesion. The tests were conducted according to JIS K 6850, comparing the maximum point stress at an ambient temperature of 23°C.

[0665] • Initial adhesion: The test pieces were sheared without special treatment.

[0666] • Adhesion after heating: The test piece was heated at 200°C for 30 minutes using a heating dryer, and then the substrate was cooled to room temperature before a shear test was performed.

[0667] • Disassemblyability evaluation: The rate of strength reduction is calculated by "(initial bond strength - bond strength after heating) / initial bond strength × 100".

[0668] • Reproducibility evaluation of disassembly: The standard deviation of “adhesive strength after heating” is evaluated using the following criteria.

[0669] A: Standard deviation less than 0.5 MPa (extremely good reproducibility)

[0670] B: Standard deviation is above 0.5 MPa and less than 1.5 MPa (good reproducibility)

[0671] C: Standard deviation above 1.5 MPa (poor reproducibility)

[0672] - The strength reduction rate is less than 10%, therefore no evaluation was conducted (no disassembly function).

[0673] The maximum point stress in the measured environment at 23℃ was compared.

[0674] <Structural Periodicity>

[0675] The cured resin was cross-sectioned using an ultrathin slicer to observe its structure periodically. The observation method employed scanning electron microscopy (SEM) to clearly distinguish surface morphology through comparative analysis.

[0676] SEM

[0677] Model used: JSM-7800F (Japan Electronics Manufacturing Co., Ltd.)

[0678] Accelerating voltage: 5kV

[0679] [Table 1]

[0680]

[0681] [Table 2]

[0682]

[0683] It should be noted that the coordination compounds shown in the table are as follows.

[0684] E-850S: Bisphenol A type liquid epoxy resin (manufactured by DIC Corporation, epoxy equivalent 188g / eq)

[0685] DICY: Dicyandiamide (“DICY7” manufactured by Mitsubishi Chemical Corporation)

[0686] DCMU: 3-(3,4-dichlorophenyl)-1,1-dimethylurea ("B-605-IM" manufactured by DIC Co., Ltd.)

[0687] DTA: Diethylenetriamine (manufactured by Kanto Chemical)

[0688] F-260D, F-190D: Thermally Expandable Capsules (Matsumoto Oils & Fats Pharmaceutical Co., Ltd.)

[0689] 953240L: Thermally Expanded Graphite (Ito Graphite Industry)

[0690] EXP 50S150: Thermally Expanded Graphite (Fuji Graphite Industry)

[0691] Examples 1 through 30 demonstrated good results in terms of flexibility, initial adhesion, strength reduction rate upon additional heating, and reproducibility of disassembly functionality. In this system, the expanding material expands upon heating, leading to damage to the adhesive layer and a reduction in the adhesive area at the adhesive layer / substrate interface. Therefore, it exhibits easy disassembly not only during heating but also after returning to room temperature.

[0692] Furthermore, the phase-separated structure of this system suggests the possibility that reversible bond units exist non-uniformly within the adhesive layer. The non-uniform existence of reversible bond structures within the soft marine phase enhances the dissociation effect based on the reverse Diels-Alder reaction upon heating. Consequently, it is speculated that heating induces softening and embrittlement of the adhesive layer, further promoting the expansion of the capsule, thus improving the reproducibility of disassembly.

[0693] Comparative Examples 1 and 4 did not contain any expanding material in their compositions, and therefore did not exhibit disintegration function. Although reversible bond dissociation (reverse Diels-Alder reaction) occurred upon heating, the bonds were re-formed (Diels-Alder reaction) due to the cooling process to room temperature, and therefore it was considered that disintegration under room temperature conditions was not exhibited.

[0694] In Comparative Examples 2 and 5, the bonding strength was highly uneven when the adhered materials were additionally heated, resulting in a lack of reproducibility in achieving the disassembly function. Since Comparative Examples 2 and 5 do not contain reversible bonds, it is speculated that the function is not fully realized solely through the effect of the expanding material.

[0695] Comparative Examples 3 and 6 resulted in very low flexibility and initial adhesion of the cured products. It is believed that in the examples, both flexibility and adhesion could be achieved through the phase separation structure formed by epoxy resin (A) and epoxy resin (B), but Comparative Examples 3 and 6 did not exhibit a phase separation structure, and therefore did not exhibit flexibility and adhesion.

Claims

1. An epoxy resin composition, characterized in that, contain: The epoxy resin (A) represented by the following general formula (1) has an epoxy equivalent of 500~10,000 g / eq. Epoxy resin (B) with an epoxy equivalent of 100~300 g / eq The following general formula (4) represents compounds (C) containing glycidyl ether groups with a molecular weight less than 1000, and Thermally expandable particles (D), [Chemistry 1] In formula (1), Ar is an independent structure containing an aromatic ring, either unsubstituted or substituent. X is a structural unit represented by the following general formula (2), and Y is a structural unit represented by the following general formula (3). [Chemistry 2] In equations (2) and (3), Ar is the same as described above. R1 and R2 are each independently a hydrogen atom, a methyl group, or an ethyl group. R' is a divalent hydrocarbon group with 2 to 12 carbon atoms. R3, R4, R7, and R8 are each independently a hydroxyl group, a glycidyl ether group, or a 2-methylglycidyl ether group. R5, R6, R9, R 10 Each can be independently a hydrogen atom or a methyl group. n1 is an integer between 4 and 16. n² is the average value of the repeating units and ranges from 2 to 30. R 11 R 12 Each is independently a glycidyl ether group or a 2-methylglycidyl ether group. R 13 R 14 Each can be independently a hydroxyl, glycidyl ether, or 2-methylglycidyl ether group. R 15 R 16 It can be a hydrogen atom or a methyl group. m1, m2, p1, p2, and q are the average values ​​of repeated samples. m1 and m2 are each independently between 0 and 25, and m1 + m2 ≥ 1. p1 and p2 are each independently represented by a value between 0 and 5. q is 0.5~5, wherein the bond between X represented by general formula (2) and Y represented by general formula (3) can be random or block, and the total number of each structural unit X and Y present in a molecule is represented by m1 and m2, respectively. [Chemistry 3] In equation (4), m3 is an integer from 1 to 4, Z 1 For any of the structures represented by the following equation (5), Z 3 For any of the structures represented by the following formula (6), a molecule may have multiple structures, which may be the same or different. [Chemistry 4] In formula (5), the aromatic ring can be substituted or unsubstituted, * indicates a bonding site, G is glycidyl or 2-methylglycidyl, and -OG on the naphthalene ring indicates that it can be bonded at any location. [Chemistry 5] In formula (6), R' is a divalent hydrocarbon group with 2 to 12 carbon atoms, R” is a hydrogen atom, methyl or ethyl, n1 is an integer from 1 to 30, n2 is the average of the number of repetitions and is 0.5 to 8, and * represents the bonding point.

2. The epoxy resin composition according to claim 1, wherein compound (I) which is reactive with the compound (C) containing a glycidyl ether group is an essential component.

3. The epoxy resin composition according to claim 2, wherein, The compound (I) that is reactive with the compound (C) containing a glycidyl ether group is a compound containing a hydroxyl group or a compound containing an amino group.

4. The epoxy resin composition according to claim 1 or 2, wherein, The concentration of reversible bonds in the compound (C) containing glycidyl ether groups is 0.10 mmol / g or more relative to the total mass of the curable components in the epoxy resin composition.

5. The epoxy resin composition according to claim 1 or 2, wherein, The mass ratio (A):(B) of the epoxy resin (A) to the epoxy resin (B) is 90:10 to 10:

90.

6. The epoxy resin composition according to claim 1 or 2, wherein, The thermally expandable particle (D) is at least one selected from the group consisting of thermally expandable microcapsules and expanded graphite.

7. The epoxy resin composition according to claim 1 or 2, wherein, The proportion of the thermally expandable particle (D) used is in the range of 3 to 40 parts by mass relative to a total of 100 parts by mass of the epoxy resin (A) and the epoxy resin (B).

8. A cured product formed by curing the epoxy resin composition of claim 2.

9. A laminate having a substrate and a layer comprising the cured material of claim 8.

10. A heat-resistant component comprising the cured product of claim 8.

11. A removable adhesive material comprising the epoxy resin composition of claim 2.

12. A disassembly method, comprising using the removable adhesive material of claim 11, comprising: The bonding process involves attaching the removable adhesive material to the surface of the substrate to bond it together. The curing process involves curing the removable adhesive material to obtain a cured product. The heat treatment process involves subjecting the cured material to heat treatment that causes the reversible bonds contained in the general formula (4) derived from the compound (C) containing the glycidyl ether group to thermal dissociation and causes the thermally expandable particles (D) to expand. The disassembly process involves separating the adhered material from the cured material.

13. The disassembly method according to claim 12, wherein, After the heat treatment process and before the disassembly process, a cooling process is further included to cool the heat-treated solidified material to room temperature.

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