epoxy resin composition

Abstract

To provide a novel epoxy resin which can give a cured product excellent in heat resistance and mechanical characteristics and is useful as electronic materials or various composite materials, and to provide an epoxy resin composition thereof.SOLUTION: The epoxy resin has a fluorene structure to the 9-position of which two aromatic hydrocarbon groups are bonded, and groups represented by the following formula (1-1) are further bonded to each of the aromatic hydrocarbon groups one by one via an ether bond. [In the formula (1-1), R4 and R5 each represent an alkylene group; R6 represents an epoxy group, a vinyl group, or an ethyl group having both a hydroxyl group and an ether group or an ester group, provided that at least one R6 is an epoxy group; x represents an integer of 1-5; y represents an integer of 0-5; and z represents an integer of 1-50.]SELECTED DRAWING: None

Description

[Technical Field]

[0001] This disclosure relates to a novel epoxy resin and an epoxy resin composition containing the epoxy resin. More specifically, it relates to a novel epoxy resin that can provide a cured product with excellent heat resistance and mechanical properties, and an epoxy resin composition containing the epoxy resin. [Background technology]

[0002] Epoxy resins generally form cured products with excellent heat resistance, mechanical properties, and electrical properties, and are therefore widely used as adhesives, paints, laminates, molded products, and other electronic materials and various composite materials.

[0003] As such an epoxy resin, the 1,2-epoxy-4-(2-oxyranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol(trimethylolpropane) [for example, trade name "EHPE3150" (manufactured by Daicel Corporation)] is highly reactive and yields cured products with excellent heat resistance, weather resistance, and electrical properties. Therefore, it is used as a curing agent for electronic materials such as encapsulants and substrates for optoelectronic semiconductors, as well as for powder coatings and various composite materials such as glass fiber binders (for example, Patent Documents 1 and 2). [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 161973 / 1983 [Patent Document 2] Japanese Patent Publication No. 2014-156591 [Overview of the project] [Problems that the invention aims to solve]

[0005] The object of the present invention is to provide a novel epoxy resin that can yield a cured product with excellent heat resistance and mechanical properties, and is useful as an electronic material or various composite material. Another object of the invention disclosed herein is to provide an epoxy resin composition that contains the novel epoxy resin, can provide a cured product with excellent heat resistance and mechanical properties, and is useful as an electronic material or various composite material. [Means for solving the problem]

[0006] The inventors of this disclosure conducted diligent research to solve the above problems and, as a result, discovered that an epoxy resin obtained by adding 1,2-epoxy-4-(2-oxyranyl)cyclohexane to a specific initiator can yield a cured product with excellent heat resistance and mechanical properties, and is useful as an electronic material or various composite material, thus completing the invention of this disclosure.

[0007] In other words, the present invention provides an epoxy resin represented by the following formula (1). [ka]

[0008] [In formula (1), ring A represents an aromatic hydrocarbon ring, either identical or different. R 1 R represents a cyano group, halogen atom, or alkyl group, either identical or different. 2 j represents a hydrocarbon group, alkoxy group, cycloalkoxy group, aryloxy group, aralkyloxy group, alkylthio group, cycloalkylthio group, arylthio group, aralkylthio group, acyl group, alkoxycarbonyl group, hydroxyl group, halogen atom, nitro group, cyano group, or substituted amino group, either identical or different. j represents an integer from 0 to 4, either identical or different. k represents an integer of 0 or greater, either identical or different. R 3 This indicates a group that is the same or different and is represented by the following formula (1-1). [ka]

[0009] [In formula (1-1), R 4 R represents an alkylene group with 2 to 4 carbon atoms.5 represents an alkylene group having 3 to 6 carbon atoms. R 6 represents any one of the groups represented by the following formulas (1a) to (1c), and R in the formula (1-1) 6 at least one of which is a group represented by the formula (1a). x represents an integer of 0 to 5. y represents an integer of 0 to 5. z represents an integer of 1 to 50. When x is an integer of 2 or more, a plurality of R 4 may be the same or different. When y is an integer of 2 or more, a plurality of R 5 may be the same or different. When z is an integer of 2 or more, a plurality of R 6 may be the same or different.] [Chemical formula] [Chemical formula] [Chemical formula]

[0010] [In the formula (1c), R 7 represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkylcarbonyl group, or a substituted or unsubstituted arylcarbonyl group.]

[0011] In the epoxy resin, ring A may be a benzene ring.

[0012] In the epoxy resin, x may be 1.

[0013] In the epoxy resin, y may be 0.

[0014] Further, the invention of the present disclosure provides an epoxy resin composition containing the epoxy resin.

[0015] The epoxy resin composition may further contain a curing agent and a curing accelerator.

[0016] The epoxy resin composition may further contain a curing catalyst.

[0017] The epoxy resin composition may further contain epoxy compounds other than the epoxy resin represented by formula (1).

[0018] In the epoxy resin composition, the epoxy compound may be an alicyclic epoxy compound.

[0019] In the epoxy resin composition, the alicyclic epoxy compound may be a compound having a cyclohexene oxide group.

[0020] In the epoxy resin composition, the alicyclic epoxy compound may be a compound represented by the following formula (I). [ka] [In formula (I), X represents a single bond or a linking group (a divalent group having one or more atoms).]

[0021] The epoxy resin composition may also be a composite resin composition.

[0022] Furthermore, the present invention provides a cured product of the epoxy resin composition.

[0023] Furthermore, the present invention provides an electronic product comprising the cured product. [Effects of the Invention]

[0024] Because the epoxy resin of this disclosure has the above-described structure, curing an epoxy resin composition containing this epoxy resin can form a cured product with excellent heat resistance and mechanical properties. Therefore, the epoxy resin of this disclosure is extremely useful as an electronic material and various composite materials. [Brief explanation of the drawing]

[0025] [Figure 1] Figure 1 shows the 1H-NMR spectrum of the epoxy resin obtained in Example 1. [Modes for carrying out the invention]

[0026] <Epoxy resin> The epoxy resin of this disclosure (hereinafter sometimes referred to as "epoxy resin (A)") is represented by the following formula (1). [ka]

[0027] In formula (1), ring A is the same or different, representing an aromatic hydrocarbon ring. The aromatic hydrocarbon ring represented by ring A includes a benzene ring or a condensed polycyclic aromatic hydrocarbon ring. The condensed polycyclic aromatic hydrocarbon ring is a condensed bicyclic hydrocarbon ring (for example, an indene ring, a naphthalene ring, etc.). 8-20 A condensed bicyclic hydrocarbon ring, preferably C 10-16 Examples include condensed bicyclic hydrocarbon rings, condensed tricyclic hydrocarbon rings (e.g., anthracene rings, phenanthrene rings, etc.), and condensed dicyclic to tetracyclic hydrocarbon rings. Preferred aromatic hydrocarbon rings include benzene rings, naphthalene rings, and anthracene rings, with benzene rings and naphthalene rings being preferred, and benzene rings being more preferred. The two rings A substituted at the 9th position of fluorene may be different rings or the same ring.

[0028] Furthermore, if ring A is a fused polycyclic aromatic hydrocarbon ring, the substitution position of ring A at position 9 of fluorene is not particularly limited. For example, the naphthyl group substituted at position 9 of fluorene may be a 1-naphthyl group, a 2-naphthyl group, etc., and a 2-naphthyl group is particularly preferred.

[0029] In formula (1), R 1The group is the same or different, representing a cyano group, a halogen atom, or an alkyl group, with alkyl groups being preferred. Examples of halogen atoms include fluorine, chlorine, and bromine atoms. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, and tert-butyl groups. 1-6 Alkyl alkyl group (preferably C 1-4 Examples include alkyl groups, especially methyl groups. Furthermore, R substituted on the two benzene rings constituting fluorene (or the fluorene skeleton) is also used. 1 They may be the same or they may be different. Also, the R relative to the benzene ring constituting fluorene. 1 The bond position (substitution position) is not particularly limited.

[0030] In formula (1), j is the same or different integer between 0 and 4, preferably between 0 and 3, more preferably 0 or 1, and even more preferably 0. Note that if j is an integer of 2 or more, multiple R in formula (1) 1 These may be the same or different. Also, in the two benzene rings constituting fluorene, j may be the same or different.

[0031] In formula (1), R 2 These represent, either identically or differently, a hydrocarbon group, alkoxy group, cycloalkoxy group, aryloxy group, aralkyloxy group, alkylthio group, cycloalkylthio group, arylthio group, aralkylthio group, acyl group, alkoxycarbonyl group, hydroxyl group, halogen atom, nitro group, cyano group, or substituted amino group. Note that R is substituted on the two rings A. 2 They may be the same or they may be different. Also, R for ring A 2 The bond position (substitution position) is not particularly limited.

[0032] Examples of hydrocarbon groups include alkyl groups (for example, methyl group, ethyl group, propyl group, isopropyl group, butyl group, s-butyl group, t-butyl group, etc.). 1-20 Alkyl alkyl group, preferably C 1-8Alkyl alkyl groups, more preferably C 1-6 Alkyl groups, etc.), cycloalkyl groups (such as cyclopentyl groups and cyclohexyl groups), etc. 5-10 Cycloalkyl groups, preferably C 5-8 Cycloalkyl groups, more preferably C 5-6 C (such as cycloalkyl groups), aryl groups [for example, phenyl groups, alkylphenyl groups (methylphenyl group (or tolyl group, 2-methylphenyl group, 3-methylphenyl group, etc.), dimethylphenyl group (xylyl group), etc.), naphthyl group, etc.)] 6-10 Aryl group, preferably C 6-8 [Aryl groups, especially phenyl groups, etc.], aralkyl groups (benzyl groups, phenethyl groups, etc. C 6-10 Aryl-C 1-4 Examples include alkyl groups, etc.

[0033] Examples of alkoxy groups include methoxy, ethoxy, propoxy, n-butoxy, isobutoxy, and tert-butoxy groups. 1-20 Alkoxy group, preferably C 1-8 Alkoxy group, more preferably C 1-6 Examples include alkoxy groups. Cycloalkoxy groups include C such as cyclohexyloxy groups. 5-10 Examples include cycloalkyloxy groups. Aryloxy groups include phenoxy groups and others. 6-10 Examples include aryloxy groups. Aralkyloxy groups include C such as the benzyloxy group. 6-10 Aryl-C 1-4 Examples include alkyloxy groups. Examples of alkylthio groups include methylthio group, ethylthio group, propylthio group, n-butylthio group, tert-butylthio group, etc. 1-20 Alkylthio group, preferably C 1-8 Alkylthio group, more preferably C 1-6 Examples include alkylthio groups. Cycloalkylthio groups include C such as cyclohexylthio groups. 5-10 Examples include cycloalkylthio groups. Arylthio groups include phenylthio groups and other C groups. 6-10Examples include arylthio groups. Examples of arylthio groups include the benzylthio group and other C groups. 6-10 Aryl-C 1-4 Examples include alkylthio groups. Examples of acyl groups include acetyl groups and other C groups. 1-6 Examples include acyl groups. Examples of alkoxycarbonyl groups include methoxycarbonyl groups and C 1-4 Examples include alkoxycarbonyl groups. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. Examples of substituted amino groups include N,N-dimethylamino groups and other N,N-diC groups. 1-6 Examples include alkylamino groups.

[0034] R 2 Preferably, the group is a hydrocarbon group, alkoxy group, cycloalkoxy group, aryloxy group, aralkyloxy group, acyl group, halogen atom, nitro group, cyano group, or substituted amino group; more preferably, a hydrocarbon group [e.g., alkyl group (e.g., C)]. 1-6 (Alkyl group), alkoxy group (C 1-4 These include alkoxy groups, halogen atoms (fluorine, chlorine, bromine, iodine, etc.), and others.

[0035] In formula (1), k is the same or different integers, representing 0 or 1 or more, preferably an integer from 0 to 8, more preferably an integer from 0 to 6, even more preferably an integer from 0 to 4, even more preferably an integer from 0 to 2, and even more preferably 0. Note that when k is an integer of 2 or more, multiple R in formula (1) 2 k may be the same or different. Also, in the two rings A, k may be the same or different.

[0036] In formula (1), R 3 R represents a group that is the same or different and is represented by the following formula (1-1). In the two rings A, R 3 They may be the same or they may be different. [ka]

[0037] In the above equation (1-1), R 4 R represents an alkylene group having 2 to 4 carbon atoms, such as an ethylene group, propylene group, trimethylene group, butylene group, tetramethylene group, etc., and ethylene groups and propylene groups are preferred due to their ease of manufacture. x represents an integer from 0 to 5, preferably an integer from 1 to 3, more preferably 1 or 2, and even more preferably 1. Note that when x is an integer of 2 or more, multiple R in formula (1-1) 4 They may be the same or they may be different.

[0038] In the above equation (1-1), R 5 represents an alkylene group having 3 to 6 carbon atoms, such as trimethylene, tetramethylene, pentamethylene, and hexamethylene. Tetramethylene and pentamethylene are preferred due to their ease of manufacture. y represents an integer from 0 to 5, preferably an integer from 0 to 3, more preferably 0 or 1, and even more preferably 0. When y is an integer of 2 or more, multiple R in formula (1-1) 5 They may be the same or they may be different.

[0039] In equation (1-1), z represents an integer between 1 and 50. The sum of z in equation (1) is an integer between 3 and 100.

[0040] In formula (1-1), R 6 R is a substituent on the cyclohexane ring shown in the formula, and represents one of the groups represented by the following formulas (1a) to (1c). 6 The bonding position is not particularly limited, but is usually the carbon atom at position 4 or 5, when the positions of the two carbon atoms of the cyclohexane ring bonded to the oxygen atom are designated as positions 1 and 2. Furthermore, if the epoxy resin (A) of this disclosure has multiple cyclohexane rings, the R in each cyclohexane ring 6 The bonding positions may be the same or different. [ka] [ka] [ka]

[0041] R in equation (1-1) 6 At least one of them is a group represented by formula (1a) (epoxy group). That is, the epoxy resin (A) of the present disclosure has at least one epoxy group in its molecule. Note that when z is an integer of 2 or more, multiple R in formula (1-1) 6 They may be the same or they may be different. Also, if the epoxy resin (A) of this disclosure has 2 or more R 6 If there is multiple R in formula (1), 6 They may be the same or they may be different.

[0042] In formula (1c), R 7 This represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkylcarbonyl group, or a substituted or unsubstituted arylcarbonyl group. Examples of alkyl groups include linear or branched alkyl groups having 1 to 20 carbon atoms, such as methyl group, ethyl group, n-propyl group, isopropyl group, butyl group, isobutyl group, s-butyl group, t-butyl group, pentyl group, hexyl group, octyl group, and 2-ethylhexyl group. Examples of alkylcarbonyl groups include alkylcarbonyl groups such as methylcarbonyl group (acetyl group), ethylcarbonyl group, n-propylcarbonyl group, isopropylcarbonyl group, n-butylcarbonyl group, isobutylcarbonyl group, s-butylcarbonyl group, and t-butylcarbonyl group. Examples of arylcarbonyl groups include benzoyl group and naphthoyl group.

[0043] Examples of substituents that the above-mentioned alkyl groups, alkylcarbonyl groups, and arylcarbonyl groups may have include substituents having 0 to 20 carbon atoms (more preferably 0 to 10 carbon atoms). Examples of the above substituents include halogen atoms such as fluorine, chlorine, bromine, and iodine atoms; hydroxyl groups; alkoxy groups such as methoxy, ethoxy, propoxy, isopropyloxy, butoxy, and isobutyloxy groups (preferably C 1-6 Alkoxy group, more preferably C 1-4 Alkoxy group; alkenyloxy group such as allyloxy group (preferably C 2-6 Alkenyloxy group, more preferably C 2-4 Alkenyloxy group; phenoxy group, tolyloxy group, naphthyloxy group, etc., with C at the aromatic ring. 1-4 Alkyl alkyl group, C 2-4 Alkenyl group, halogen atom, C 1-4 An aryloxy group (preferably C) which may have substituents such as an alkoxy group. 6-14 Araryloxy group; Aralkyloxy group such as benzyloxy group, phenethyloxy group, etc. (preferably C 7-18 Aralkyloxy group); Acyloxy group such as acetyloxy group, propionyloxy group, (meth)acryloyloxy group, benzoyloxy group, etc. (preferably C 1-12 Acyloxy group; mercapto group; alkylthio group such as methylthio group, ethylthio group (preferably C 1-6 Alkylthio group, more preferably C 1-4 Alkylthio group; alkenylthio group such as allylthio group (preferably C 2-6 Alkenylthio group, more preferably C 2-4 Alkenylthio group; phenylthio group, tolthio group, naphthylthio group, etc., with C at the aromatic ring. 1-4 Alkyl alkyl group, C 2-4 Alkenyl group, halogen atom, C 1-4 An arylthio group (preferably C) which may have substituents such as an alkoxy group. 6-14 Aralkylthio groups such as benzylthio groups and phenethylthio groups (preferably C 7-18an aralkylthio group); a carboxy group; an alkoxycarbonyl group such as a methoxycarbonyl group, an ethoxycarbonyl group, a propoxycarbonyl group, or a butoxycarbonyl group (preferably a C 1-6 alkoxy-carbonyl group); an aryloxycarbonyl group such as a phenoxycarbonyl group, a tolyloxycarbonyl group, or a naphthyloxycarbonyl group (preferably a C 6-14 aryloxy-carbonyl group); an aralkyloxycarbonyl group such as a benzyloxycarbonyl group (preferably a C 7-18 aralkyloxy-carbonyl group); an amino group; a mono- or dialkylamino group such as a methylamino group, an ethylamino group, a dimethylamino group, or a diethylamino group (preferably a mono- or di-C 1-6 alkylamino group); an acylamino group such as an acetylamino group, a propionylamino group, or a benzoylamino group (preferably a C 1-11 acylamino group); an oxetanyl group-containing group such as an ethyloxetanyloxy group; an acyl group such as an acetyl group, a propionyl group, or a benzoyl group; an oxo group; a group in which two or more of these are bonded via a C 1-6 alkylene group, etc. may be mentioned.

[0044] In the epoxy resin (A) of the present disclosure, the ratio of the group (epoxy group) represented by the formula (1a) to the total amount (100 mol%) of R 6 is not particularly limited, but is preferably 40 mol% or more (for example, 40 to 100 mol%), more preferably 60 mol% or more, and still more preferably 80 mol% or more. If the above ratio is less than 40 mol%, the heat resistance and mechanical properties of the cured product may be insufficient. The above ratio can be calculated by, for example, 1 H-NMR spectrum measurement or oxirane oxygen concentration measurement.

[0045] As one embodiment of the epoxy resin (A) of the present disclosure, an epoxy resin which is a group in which ring A is a benzene ring, x is 1, and y is 0 is preferable.

[0046] The epoxy resin (A) of the present disclosure is not particularly limited, but is produced by subjecting a hydroxyl group-containing fluorene compound represented by the following formula (2) as an initiator (i.e., starting from the hydroxyl group (active hydrogen) of the compound), ring-opening polymerizing (cationic polymerizing) 1,2-epoxy-4-vinylcyclohexane (3-vinyl-7-oxabicyclo[4.1.0]heptane), and then epoxidizing with an oxidizing agent. [Chemical formula]

[0047] In the above formula (2), R 3a represents a group represented by the following formula (2-1), which may be the same or different. In the two rings A, R 3a may be the same or different. In the above formula (2), the definitions, examples, and preferred embodiments of the ring A, R 1 , R 2 , j, and k are the same as those of the ring A, R 1 , R 2 , j, and k in the above formula (1). [Chemical formula]

[0048] In the above formula (2-1), the definitions, examples, and preferred embodiments of R 4 , R 5 , x, and y are the same as those of R 4 , R 5 , x, and y in the above formula (1-1).

[0049] The hydroxyl group-containing fluorene compound represented by the formula (2) can be produced by a known method. For example, using a compound in which R 3a is a hydrogen atom in the above formula (2) as a starting material, and following the method described in, for example, JP-A-2009-155256, C such as ethylene oxide and propylene oxide 2-4By ring-opening addition polymerization of alkylene oxide, a hydroxyl group-containing fluorene compound represented by formula (2) can be produced, where x is an integer from 1 to 5 and y is 0 in formula (2-1). 1-4 Ring-opening polymerization of alkylene oxides may be carried out using different types of alkylene oxides, or different types of alkylene oxides may be polymerized stepwise. For example, by ring-opening polymerization of ethylene oxide followed by ring-opening polymerization of propylene oxide, x is an integer of 2 or more, and multiple R 4 This allows for the production of hydroxyl group-containing fluorene compounds represented by different formulas (2).

[0050] Furthermore, if necessary, a hydroxyl group-containing fluorene compound represented by formula (2) in which y in formula (2-1) is 0 can be produced by ring-opening addition polymerization of a lactone compound such as δ-valerolactone or ε-caprolactone to a hydroxyl group-containing fluorene compound represented by formula (2) in which y in formula (2-1) is 0, according to a conventional method.

[0051] Commercially available hydroxyl group-containing fluorene compounds represented by formula (2) can also be used. Examples of commercially available hydroxyl group-containing fluorene compounds represented by formula (2) include 9,9-bis[4-(2-hydroxyethoxy)phenyl]fluorene [trade name "BPEF", manufactured by Osaka Gas Chemical Co., Ltd.], 9,9-bis(4-hydroxyphenyl)fluorene [trade name "BPF", manufactured by Osaka Gas Chemical Co., Ltd.], and 9,9-bis(4-hydroxy-3-methylphenyl)fluorene [trade name "BCF", manufactured by Osaka Gas Chemical Co., Ltd.].

[0052] In particular, epoxy resin (A) is preferably an epoxy resin produced by ring-opening polymerization of 1,2-epoxy-4-vinylcyclohexane using a hydroxyl group-containing fluorene compound represented by formula (2) as an initiator in the presence of a cationic polymerization catalyst containing a fluorine atom, and then epoxidizing it with an oxidizing agent, from the viewpoint of mold release properties during molding.

[0053] The above-mentioned 1,2-epoxy-4-vinylcyclohexane can be produced by known or conventional methods and is not particularly limited, but for example, it can be obtained by partially epoxidizing 4-vinylcyclohexene, which is obtained by the dimerization reaction of butadiene, using an oxidizing agent such as peracetic acid. Alternatively, commercially available products (for example, trade name "Celoxide 2000" manufactured by Daicel Corporation) can be used as 1,2-epoxy-4-vinylcyclohexane.

[0054] The amount of 1,2-epoxy-4-vinylcyclohexane used can be appropriately selected depending on the desired degree of polymerization (z in formula (1-1)) of 1,2-epoxy-4-vinylcyclohexane in the epoxy resin (A). For example, it can be appropriately selected from a range of 1 to 20 equivalents, preferably 2 to 15 equivalents, and more preferably 3 to 10 equivalents, relative to the hydroxyl groups of the hydroxyl group-containing fluorene compound represented by formula (2).

[0055] Examples of cationic polymerization catalysts containing fluorine atoms include Brønsted acids and Lewis acids having fluorine atoms, and are not particularly limited, but examples include boron trifluoride, boron trifluoride etherate (e.g., diethyl ether complex of boron trifluoride), etc. The amount of cationic polymerization catalyst containing fluorine atoms used is not particularly limited, but can be appropriately selected from 0.01 to 10 parts by weight (more preferably 0.1 to 5 parts by weight) per 100 parts by weight of 1,2-epoxy-4-vinylcyclohexane.

[0056] The temperature (reaction temperature) for ring-opening polymerization of 1,2-epoxy-4-vinylcyclohexane is not particularly limited, but is preferably -70 to 200°C, and more preferably -30 to 100°C. The reaction time can be appropriately adjusted depending on the conversion rate of 1,2-epoxy-4-vinylcyclohexane, etc.

[0057] The ring-opening polymerization of 1,2-epoxy-4-vinylcyclohexane can also be carried out in a solvent. However, solvents containing active hydrogen cannot be used. Specifically, suitable solvents include ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; aromatic hydrocarbons such as benzene, toluene, and xylene; ethers such as diethyl ether; aliphatic hydrocarbons such as hexane and heptane; and esters such as ethyl acetate. Note that a single solvent may be used, or two or more solvents may be used in combination.

[0058] Ring-opening polymerization of 1,2-epoxy-4-vinylcyclohexane using the hydroxyl group-containing fluorene compound represented by formula (2) above as an initiator produces a compound represented by formula (3) below (a resin having a vinyl group). This compound can be subjected to the next reaction (epoxidation) as is, or it can be purified before the next reaction. The purification method is not particularly limited, and known or conventional methods such as separation methods such as filtration, concentration, distillation, extraction, crystallization, recrystallization, column chromatography, or separation methods combining these can be used. [ka]

[0059] In equation (3) above, R 3b R represents a group that is the same or different and is represented by the following formula (3-1). In the two rings A, R 3b They may be the same or they may be different. In formula (3) above, ring A, R 1 , R 2 The definitions, examples, and preferred embodiments of rings A, R in formula (1) above are given by... 1 , R 2 It is the same as j and k. [ka]

[0060] In the above equation (3-1), R 4 , R 5The definitions, examples, and preferred embodiments of x, y, and z in formula (1-1) above are as follows: 4 , R 5 It is the same as x, y, and z.

[0061] The ring-opening polymerization described above can be carried out more specifically, for example, according to the method described in Japanese Patent Publication No. 60-161973.

[0062] Next, epoxy resin (A) (epoxy resin represented by formula (1)) is obtained by epoxidizing the vinyl group of the compound represented by formula (3) with an oxidizing agent.

[0063] The oxidizing agent used is not particularly limited to known or conventional oxidizing agents such as hydrogen peroxide or organic peracids, but examples of organic peracids include formic acid, peracetic acid, perbenzoic acid, and trifluoroperacetic acid. Among these, peracetic acid is preferred because it is industrially available at low cost and has high stability. The oxidizing agent can be used alone or in combination of two or more.

[0064] When reacting (epoxidizing) the compound represented by formula (3) with an organic peracid, known or conventional catalysts can also be used. Examples of such catalysts include alkalis such as sodium carbonate and acids such as sulfuric acid.

[0065] The above reaction (epoxidation) can be carried out by determining whether or not to use a solvent and adjusting the reaction temperature, depending on the equipment used and the physical properties of the raw materials.

[0066] The temperature at which the above reaction proceeds (reaction temperature) can be appropriately determined depending on the reactivity of the oxidizing agent used, and is not particularly limited. However, for example, when peracetic acid is used as the oxidizing agent, it is preferable to set the temperature to 0 to 70°C. If the reaction temperature is below 0°C, the reaction may proceed too slowly, while if the reaction temperature exceeds 70°C, decomposition of peracetic acid may occur more easily.

[0067] In the above reaction, a solvent may be used to reduce the viscosity of the raw materials or to stabilize the oxidizing agent by diluting it. When peracetic acid is used as the oxidizing agent, for example, aromatic hydrocarbons such as benzene, toluene, xylene, and ethylbenzene; ethers such as diethyl ether; esters such as ethyl acetate; and ketones such as acetone, methyl isobutyl ketone, and methyl ethyl ketone may be used as solvents.

[0068] The amount of oxidizing agent used relative to the vinyl groups of the compound represented by formula (3) in the above reaction (molar ratio) is not particularly limited, but for example, when using peracetic acid as the oxidizing agent, it is preferable to use an amount of 1 to 1.5 times the molar amount relative to the vinyl groups.

[0069] Through the above reaction, some or all of the vinyl groups of the compound represented by formula (3) are epoxidized and converted into the group represented by formula (1a) (epoxy group), thereby producing the epoxy resin represented by formula (1) (epoxy resin (A)). The group represented by formula (1c) in formula (1) is produced, for example, by the reaction (side reaction) of an organic acid (e.g., acetic acid) produced by the reaction of the vinyl group of the compound represented by formula (3) with an organic peracid, or by water, alcohol, etc., present in the system with the group represented by formula (1a). The proportion (ratio) of the groups represented by formulas (1a) to (1c) in formula (1) can be appropriately adjusted, for example, by the type of oxidizing agent, the amount of oxidizing agent used (molar ratio of oxidizing agent to vinyl group), and the reaction conditions.

[0070] The epoxy resin (A) obtained by the above reaction can be purified by known or conventional methods such as separation means such as filtration, concentration, distillation, extraction, crystallization, recrystallization, column chromatography, or separation means combining these.

[0071] The epoxy resin (A) may consist of one type of epoxy resin represented by formula (1), or it may consist of two or more types of epoxy resin represented by formula (1).

[0072] The weight-average molecular weight of epoxy resin (A) on a standard polystyrene basis is not particularly limited, but is preferably 300 to 100,000, and more preferably 1,000 to 10,000. If the weight-average molecular weight is less than 300, the mechanical properties and heat resistance of the cured product may be insufficient. On the other hand, if the weight-average molecular weight exceeds 100,000, the viscosity may increase, and the fluidity during molding may decrease. The weight-average molecular weight can be measured, for example, by gel permeation chromatography (GPC).

[0073] The epoxy equivalent of epoxy resin (A) is not particularly limited, but is preferably 50 to 1000, and more preferably 100 to 500. If the epoxy equivalent is less than 50, the cured product may become brittle. On the other hand, if the epoxy equivalent exceeds 1000, the mechanical properties of the cured product may be insufficient. The epoxy equivalent can be measured, for example, in accordance with JIS K7236:2001.

[0074] The epoxy resin (A) is not particularly limited, but may contain fluorine atoms. For example, when the above ring-opening polymerization is carried out in the presence of a cationic polymerization catalyst containing fluorine atoms, the resulting epoxy resin (A) tends to contain fluorine atoms. The fluorine atom content in epoxy resin (A) is not particularly limited, but is preferably 100 to 30,000 ppm, and more preferably 2,000 to 15,000 ppm. If the fluorine atom content is less than 100 ppm, the mold release properties of the cured product may be insufficient. On the other hand, if the fluorine atom content exceeds 30,000 ppm, delamination at the interface with metals or other resins may occur easily. The fluorine atom content can be measured, for example, by combustion ion chromatography. The form in which fluorine atoms are included in epoxy resin (A) is not particularly limited, but examples include being included as a constituent element of the epoxy resin, or being included as a constituent element of a component other than the epoxy resin (impurity, etc.). For example, it may be included in a form in which at least one hydrogen atom bonded to a carbon atom in the epoxy resin represented by formula (1) is substituted. The presence of CF bonds in the epoxy resin represented by formula (1) is, for example, 1 This can be confirmed by methods such as 1H-NMR spectroscopy.

[0075] <Epoxy resin composition> The epoxy resin composition of this disclosure is a curable resin composition containing epoxy resin (A) as an essential component, wherein epoxy resin (A) is an epoxy resin represented by the above formula (1). In addition to the above essential component, the epoxy resin composition of this disclosure may contain other components as needed. Furthermore, in the epoxy resin composition of this disclosure, epoxy resin (A) can be used alone or in combination of two or more types.

[0076] The content (amount) of epoxy resin (A) in the epoxy resin composition of this disclosure is not particularly limited, but is preferably 2 to 90% by weight, more preferably 4 to 80% by weight, and even more preferably 6 to 70% by weight, based on the total amount (100% by weight) of the epoxy resin composition. If the content of epoxy resin (A) is less than 2% by weight, the heat resistance and mechanical properties of the cured product may be insufficient. On the other hand, if the content of epoxy resin (A) exceeds 90% by weight, the viscosity may become too high, reducing the ease of handling.

[0077] The ratio of epoxy resin (A) to the total amount (100% by weight) of epoxy compound (epoxy resin) contained in the epoxy resin composition of this disclosure is not particularly limited, but is preferably 2% by weight or more (for example, 2 to 100% by weight), more preferably 4% by weight or more, and even more preferably 6% by weight or more. If the ratio of epoxy resin (A) is less than 2% by weight, the heat resistance and mechanical properties (strength, elongation, etc.) of the cured product tend to be insufficient.

[0078] [Other epoxy compounds] The epoxy resin composition of this disclosure may contain epoxy compounds other than epoxy resin (A) (sometimes referred to as "other epoxy compounds"), to the extent that they do not impair the effects of the invention of this disclosure. Other epoxy compounds mentioned above include, but are not limited to, known or commonly used epoxy compounds, such as aromatic epoxy compounds such as aromatic glycidyl ether epoxy compounds [e.g., bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, biphenol type epoxy compounds, phenol novolac type epoxy compounds, cresol novolac type epoxy compounds, cresol novolac type epoxy compounds of bisphenol A, naphthalene type epoxy compounds, epoxy compounds obtained from trisphenolmethane, etc.]; aliphatic epoxy compounds such as aliphatic glycidyl ether epoxy compounds [e.g., aliphatic polyglycidyl ethers, etc.]; (i) compounds having an epoxy group (alicyclic epoxy group) composed of two adjacent carbon atoms and an oxygen atom constituting an alicyclic ring (aliphatic hydrocarbon ring); (ii) compounds in which an epoxy group is directly bonded to an alicyclic ring by a single bond (excluding epoxy resin (A)); and (iii) alicyclic epoxy compounds such as hydrogenated aromatic glycidyl ether epoxy compounds. Note that other epoxy compounds can be used individually or in combination of two or more.

[0079] As the compound having the alicyclic epoxy group described above (i), any known or commonly used compound may be arbitrarily selected and used. Among these, the cyclohexene oxide group is preferred as the alicyclic epoxy group. That is, as the compound having the alicyclic epoxy group (i), a compound having a cyclohexene oxide group is preferred from the viewpoint of the transparency and heat resistance of the cured product, and in particular, a compound represented by the following formula (I) (alicyclic epoxy compound) is preferred. [ka]

[0080] In formula (I), X represents a single bond or a linking group (a divalent group having one or more atoms). Examples of such linking groups include divalent hydrocarbon groups, carbonyl groups, ether bonds, ester bonds, carbonate groups, amide groups, and groups formed by linking multiple such groups.

[0081] Examples of compounds in which X in formula (I) is a single bond include 3,4,3',4'-diepoxybicyclohexane.

[0082] Examples of the above-mentioned divalent hydrocarbon groups include linear or branched alkylene groups having 1 to 18 carbon atoms, and divalent alicyclic hydrocarbon groups. Examples of linear or branched alkylene groups having 1 to 18 carbon atoms include methylene groups, methylmethylene groups, dimethylmethylene groups, ethylene groups, propylene groups, and trimethylene groups. Examples of the above-mentioned divalent alicyclic hydrocarbon groups include divalent cycloalkylene groups (including cycloalkylidene groups) such as 1,2-cyclopentylene groups, 1,3-cyclopentylene groups, cyclopentylidene groups, 1,2-cyclohexylene groups, 1,3-cyclohexylene groups, 1,4-cyclohexylene groups, and cyclohexylidene groups.

[0083] The above-mentioned linking group X is particularly preferably a linking group containing an oxygen atom, specifically -CO-, -O-CO-O-, -COO-, -O-, -CONH-; a group in which multiple of these groups are linked; a group in which one or more of these groups are linked to one or more of a divalent hydrocarbon group. Examples of divalent hydrocarbon groups are those exemplified above.

[0084] Typical examples of alicyclic epoxy compounds represented by formula (I) above include the compounds represented by formulas (I-1) to (I-10) below. In formulas (I-5) and (I-7) below, l and m represent integers from 1 to 30, respectively. In formula (I-5) below, R is an alkylene group having 1 to 8 carbon atoms, and examples include linear or branched alkylene groups such as methylene, ethylene, propylene, isopropylene, butylene, isobutylene, s-butylene, pentylene, hexylene, heptylene, and octylene groups. Among these, linear or branched alkylene groups having 1 to 3 carbon atoms, such as methylene, ethylene, propylene, and isopropylene groups, are preferred. In formulas (I-9) and (I-10) below, n1 to n6 represent integers from 1 to 30, respectively. [ka] [ka]

[0085] (ii) Examples of compounds in which an epoxy group is directly bonded to an alicyclic ring by a single bond include the compound represented by the following formula (II). Specifically, examples of the above compound include 3,4-epoxycyclohexylmethyl(3,4-epoxy)cyclohexanecarboxylate represented by the above formula (I-1), trade name "Celoxide 2021P" (manufactured by Daicel Corporation). [ka]

[0086] In formula (II), R' represents a p-valent organic group. p represents an integer from 1 to 20. q represents an integer from 1 to 50, and the sum of q in formula (II) is an integer from 3 to 100. R'' represents R in formula (1-1) above. 6Similarly, it represents any of the groups represented by formulas (1a) to (1c) above. However, at least one of the R'' in formula (II) is the group represented by formula (1a). When p is 2 or greater, the q in each group in parentheses may be the same or different. Specific examples of the above compounds include the 1,2-epoxy-4-(2-oxyranyl)cyclohexane adduct of 2,2-bis(hydroxymethyl)-1-butanol(trimethyl-lpropane), trade name "EHPE3150" (manufactured by Daicel Corporation).

[0087] (iii) Examples of hydrogenated glycidyl ether epoxy compounds include hydrogenated compounds of bisphenol A type epoxy compounds such as 2,2-bis[4-(2,3-epoxypropoxy)cyclohexyl]propane and 2,2-bis[3,5-dimethyl-4-(2,3-epoxypropoxy)cyclohexyl]propane (hydrogenated bisphenol A type epoxy compounds); bis[o,o-(2,3-epoxypropoxy)cyclohexyl]methane, bis[o,p-(2,3-epoxypropoxy)cyclohexyl]methane, bis[p,p-(2,3-epoxypropoxy] Examples include hydrogenated compounds of bisphenol F type epoxy compounds such as [poxy)cyclohexyl]methane and bis[3,5-dimethyl-4-(2,3-epoxypropoxy)cyclohexyl]methane (hydrogenated bisphenol F type epoxy compounds); hydrogenated biphenol type epoxy compounds; hydrogenated phenol novolac type epoxy compounds; hydrogenated cresol novolac type epoxy compounds; hydrogenated cresol novolac type epoxy compounds of bisphenol A; hydrogenated naphthalene type epoxy compounds; and hydrogenated epoxy compounds of epoxy compounds obtained from trisphenolmethane.

[0088] The content (amount) of other epoxy compounds in the epoxy resin composition of this disclosure is not particularly limited, but is preferably less than 70% by weight (for example, 0% or more and less than 70% by weight) relative to the total amount (100% by weight) of epoxy compounds (epoxy resin) contained in the epoxy resin composition, and more preferably less than 60% by weight. If the content of other epoxy compounds is 70% by weight or more, the heat resistance and mechanical properties of the cured product may be insufficient. On the other hand, although the content (amount) of other epoxy compounds is not particularly limited, is preferably 10% by weight or more and more preferably 20% by weight or more, relative to the total amount (100% by weight) of epoxy compounds (epoxy resin) contained in the epoxy resin composition. If the content of other epoxy compounds is less than 20% by weight, the viscosity may become too high and handling may be impaired.

[0089] [Hardening agent] The epoxy resin composition of this disclosure may contain, in addition to the epoxy resin (A), a curing agent (hereinafter sometimes referred to as curing agent (B)). The curing agent (B) is a compound that reacts with a compound having an epoxy group, such as the epoxy resin (A), to cure the epoxy resin composition. As curing agent (B), any known or conventional curing agent for epoxy resins can be used, and is not particularly limited, but examples include acid anhydride-based curing agents, amine-based curing agents, imidazole-based curing agents, and polymercaptan-based curing agents. The curing agent (B) can be used alone or in combination of two or more types. Among these, an acid anhydride-based curing agent is preferred as curing agent (B).

[0090] Examples of the above-mentioned acid anhydride-based curing agents include acid anhydrides that are liquid at 25°C, such as methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, dodecenyl succinic anhydride, and methylendomethylenetetrahydrophthalic anhydride, as well as acid anhydrides that are solid at 25°C, such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and methylcyclohexendicarboxylic acid anhydride. These acid anhydride-based curing agents can be used individually or in combination of two or more types.

[0091] Commercially available products can also be used as the hardening agent (B). For example, commercially available acid anhydride-based hardening agents include the product names "Ricacid MH-700", "Ricacid MH-700F", and "Ricacid HH" (all manufactured by Shin Nippon Rika Co., Ltd.); and "HN-5500" (manufactured by Hitachi Chemical Co., Ltd.).

[0092] The content (amount) of curing agent (B) in the epoxy resin composition of this disclosure is not particularly limited, but is preferably 50 to 200 parts by weight, and more preferably 70 to 150 parts by weight, per 100 parts by weight of the total amount of epoxy group-containing compounds contained in the epoxy resin composition. More specifically, it is preferable to use curing agent (B) in a ratio of 0.5 to 1.5 equivalents per equivalent of epoxy groups in all epoxy group-containing compounds contained in the epoxy resin composition of this disclosure. If the content of curing agent (B) is less than 50 parts by weight, curing may not proceed sufficiently, resulting in insufficient toughness of the cured product or reduced resistance to yellowing of the cured product. On the other hand, if the content of curing agent (B) exceeds 200 parts by weight, curing may similarly be insufficient, and the cured product may become discolored and its hue may deteriorate.

[0093] [Curing accelerator] The epoxy resin composition of this disclosure may further contain a curing accelerator (hereinafter sometimes referred to as curing accelerator (C)). The curing accelerator (C) is a compound that has the function of accelerating the curing rate when a compound having an epoxy group, such as an epoxy resin (A), is cured by a curing agent (B). As the curing accelerator (C), known or conventional curing accelerators can be used, for example, 1,8-diazabicyclo[5.4.0]undecene-7 (DBU) or its salts (e.g., phenol salt, octyl salt, p-toluenesulfonate, formate, tetraphenylborate salt); 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) or its salts (e.g., phenol salt, octyl salt, p-toluenesulfonate, formate, tetraphenylborate salt); benzyl dimethyl Examples include tertiary amines such as ethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and N,N-dimethylcyclohexylamine; imidazoles such as 2-ethyl-4-methylimidazole and 1-cyanoethyl-2-ethyl-4-methylimidazole; phosphines such as phosphate esters and triphenylphosphine; phosphonium compounds such as tetraphenylphosphonium tetra(p-tolyl)borate; organometallic salts such as zinc octate and tin octate; and metal chelates. Curing accelerators can be used individually or in combination of two or more types.

[0094] Furthermore, commercially available products such as "U-CAT SA 506," "U-CAT SA 102," "U-CAT 5003," "U-CAT 18X," and "12XD" (development product) (all manufactured by Sunapro Co., Ltd.); "TPP-K" and "TPP-MK" (both manufactured by Hokko Chemical Industry Co., Ltd.); and "PX-4ET" (manufactured by Nippon Chemical Industrial Co., Ltd.) can also be used as curing accelerators.

[0095] The content (amount) of the curing accelerator (C) in the epoxy resin composition of this disclosure is not particularly limited, but is preferably 0.1 to 8 parts by weight, and more preferably 0.3 to 5 parts by weight, per 100 parts by weight of the total amount of epoxy group-containing compounds contained in the epoxy resin composition. If the content of curing accelerator (C) is less than 0.1 parts by weight, curing may be insufficient. On the other hand, if the content of curing accelerator (C) exceeds 8 parts by weight, the shelf life may be poor, or the cured product may become discolored and its hue may deteriorate.

[0096] [Curing catalyst] The epoxy resin composition of this disclosure may contain a curing catalyst (hereinafter sometimes referred to as curing catalyst (D)) instead of the curing agent (B) described above. Similar to the case in which curing agent (B) is used, by using curing catalyst (D), the curing reaction of a compound having epoxy groups, such as epoxy resin (A), can be advanced and a cured product can be obtained. The curing catalyst (D) is not particularly limited, but for example, a cationic catalyst (cationic polymerization initiator) that generates cationic species by ultraviolet irradiation or heat treatment and initiates polymerization can be used.

[0097] Examples of cationic catalysts that generate cation species upon ultraviolet irradiation include hexafluoroantimonate salts, pentafluorohydroxyantimonate salts, hexafluorophosphate salts, and hexafluoroalzenate salts. These cationic catalysts can be used individually or in combination of two or more. Commercially available cationic catalysts such as "UVACURE1590" (manufactured by Daicel Cytec Co., Ltd.), "CD-1010", "CD-1011", and "CD-1012" (all manufactured by Sartomer, USA), "Irgacure 264" (manufactured by Ciba Japan Co., Ltd.), and "CIT-1682" (manufactured by Nippon Soda Co., Ltd.) can also be preferably used.

[0098] Cationic catalysts that generate cation species by heat treatment include, for example, aryldiazonium salts, aryliodonium salts, arylsulfonium salts, and allene-ion complexes. These cationic catalysts can be used individually or in combination of two or more. Commercially available cationic catalysts such as "PP-33," "CP-66," and "CP-77" (all manufactured by ADEKA Corporation), "FC-509" (manufactured by 3M), "UVE1014" (manufactured by GE), "San-Aid SI-60L," "San-Aid SI-80L," "San-Aid SI-100L," "San-Aid SI-110L," and "San-Aid SI-150L" (all manufactured by Sanshin Chemical Industry Co., Ltd.), and "CG-24-61" (manufactured by Chiba Japan Co., Ltd.) can be preferably used. As the above-mentioned cationic catalyst, compounds of chelates of metals such as aluminum and titanium with acetoacetic acid or diketones and silanols such as triphenylsilanol, or compounds of chelates of metals such as aluminum and titanium with acetoacetic acid or diketones and phenols such as bisphenol S can also be used.

[0099] The amount (content) of the curing catalyst (D) used is not particularly limited, but is preferably 0.01 to 15 parts by weight, more preferably 0.01 to 12 parts by weight, even more preferably 0.05 to 10 parts by weight, and most preferably 0.1 to 10 parts by weight, relative to the total amount (100 parts by weight) of the epoxy group-containing compounds contained in the epoxy resin composition. By using the curing catalyst (D) within the above range, a cured product with excellent heat resistance and light resistance can be obtained.

[0100] [Additives] The epoxy resin composition of this disclosure may contain various additives in addition to the components described above, as long as they do not impair the effects of the invention of this disclosure. For example, including compounds having hydroxyl groups such as ethylene glycol, diethylene glycol, propylene glycol, and glycerin as additives can slow down the reaction. In addition, conventional additives such as defoamers, leveling agents, silane coupling agents such as γ-glycidoxypropyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane, surfactants, inorganic fillers such as silica and alumina, flame retardants, colorants, antioxidants, ultraviolet absorbers, ion adsorbents, pigments, phosphors (for example, inorganic phosphors such as YAG-based phosphors and silicate-based phosphors), and mold release agents can be used, as long as they do not impair viscosity or transparency.

[0101] The epoxy resin compositions of this disclosure are not particularly limited, but can be prepared by blending and kneading the above-mentioned components while heating as needed. The kneading method is not particularly limited, and known or conventional kneading means such as various mixers such as dissolvers and homogenizers, kneaders, rolls, bead mills, and self-rotating agitators can be used.

[0102] The epoxy resin composition of this disclosure is preferably liquid at room temperature (25°C) in terms of handling and processability, and preferably has a viscosity (25°C) of 100,000 mPa·s or less (for example, 200 to 100,000 mPa·s), and more preferably 50,000 mPa·s or less (for example, 200 to 50,000 mPa·s). The glass transition temperature is preferably 120 to 200°C, and more preferably 130 to 180°C. The viscosity can be measured by the measurement method described in the examples.

[0103] Furthermore, a B-staged epoxy resin composition (an epoxy resin composition in a B-stage state) can also be obtained by further heating the epoxy resin composition and reacting a portion of the epoxy group-containing compounds in the epoxy resin composition.

[0104] <Cured product> By curing the epoxy resin composition of this disclosure (or the epoxy resin composition in the B-stage state) by heating, a cured product (sometimes referred to as "the cured product of this disclosure") with excellent heat resistance and mechanical properties (especially strength and elongation) can be obtained. The heating temperature during curing (curing temperature) is not particularly limited, but is preferably 45 to 200°C, more preferably 100 to 190°C, and even more preferably 100 to 180°C. The heating time during curing (curing time) is not particularly limited, but is preferably 30 to 600 minutes, more preferably 45 to 540 minutes, and even more preferably 60 to 480 minutes. If the curing temperature and curing time are lower than the lower limit of the above range, curing will be insufficient, and conversely, if they are higher than the upper limit of the above range, decomposition of the resin components may occur, so neither is desirable. The curing conditions depend on various conditions, but can be appropriately adjusted by shortening the curing time when the curing temperature is high, and lengthening the curing time when the curing temperature is low. Furthermore, while the heat curing process may be carried out in a single step, it may also be carried out by gradually increasing the temperature to prevent cracking during the curing process due to heat generation.

[0105] The degree of hardening of the cured product of this disclosure is preferably 90% or more, more preferably 95% or more, and even more preferably 97% or more. If the degree of hardening of the cured product of this disclosure is less than 90%, the heat resistance and mechanical properties may be insufficient. Furthermore, the degree of curing of the cured product of this disclosure can be calculated by measuring the heat generated by the epoxy resin composition of this disclosure and the heat generated by the cured product of this disclosure using DSC, and using the following formula. Degree of curing (%) = [1 - (Heat generation from cured material / Heat generation from epoxy resin composition)] × 100 The degree of hardening described above can be measured more specifically by the measurement method described in the examples.

[0106] The glass transition temperature (Tg) of the cured product of this disclosure (for example, a cured product with a degree of hardening of 90% or more) is preferably 100°C or higher (for example, 100 to 250°C), and more preferably 140°C or higher (for example, 140 to 250°C). If the glass transition temperature is less than 100°C, the heat resistance of the cured product may be insufficient depending on the application. The glass transition temperature of the cured product can be measured by various thermal analyses (DSC (differential scanning calorimeter), TMA (thermomechanical analyzer), etc.) or dynamic viscoelasticity measurements, and more specifically, by the measurement methods described in the examples.

[0107] The coefficient of linear expansion (α1) of the cured product of this disclosure (e.g., a cured product with a degree of hardening of 90% or more) below the glass transition temperature is preferably 40 to 100 ppm / °C, and more preferably 70 to 95 ppm / °C. Furthermore, the coefficient of linear expansion (α2) of the cured product of this disclosure (e.g., a cured product with a degree of hardening of 90% or more) above the glass transition temperature is preferably 90 to 170 ppm / °C, and more preferably 90 to 160 ppm / °C. The coefficients of linear expansion α1 and α2 of the cured product can be measured using TMA or the like, and more specifically, by the measurement method described in the examples.

[0108] The 5% weight loss temperature (T) of the cured product of this disclosure (e.g., a cured product with a degree of curing of 90% or more) d5 The temperature is not particularly limited, but is preferably 330°C or higher (for example, 330-450°C), more preferably 340°C or higher, and even more preferably 350°C or higher. A 5% weight loss temperature of 330°C or higher tends to further improve the heat resistance of the cured product.

[0109] The flexural strength of the cured product of this disclosure (for example, a cured product with a degree of hardening of 90% or more) is not particularly limited, but is preferably 40 MPa or more (for example, 40 to 200 MPa), and more preferably 70 MPa or more (for example, 40 to 200 MPa). Furthermore, the flexural modulus of the cured product of this disclosure (for example, a cured product with a degree of hardening of 90% or more) is not particularly limited, but is preferably 1500 MPa or more (for example, 1500 to 2000 MPa), and more preferably 1800 MPa or more. Furthermore, the flexural elongation of the cured product of this disclosure (for example, a cured product with a degree of hardening of 90% or more) is not particularly limited, but is preferably 2.0% or more (for example, 2.0 to 20%), and more preferably 2.5% or more (for example, 2.5 to 20%). The bending strength, bending modulus, and bending elongation of the above-mentioned cured material can be measured, for example, in accordance with JIS K6911 (for example, under conditions of a bending speed of 2 mm / min), and more specifically, they can be measured by the measurement method described in the examples.

[0110] The epoxy resin composition of this disclosure can be cured to form a cured product (cured product of this disclosure) with excellent heat resistance and mechanical properties, and can therefore be suitably used as an electronic material or various composite material.

[0111] In other words, the epoxy resin composition and its cured product (cured product of the disclosure) are useful as a wide range of electrical and electronic materials, such as insulating materials between layers of electronic components, solder resists and coverlays for printed circuit boards, semiconductor encapsulating materials, color filters, printing inks, encapsulants (such as semiconductor encapsulants), paints, coatings, and adhesives. They can also be used in fields such as molding materials, adhesives, paints, electrical insulating materials, laminates, coatings, inks, paints, sealants, resists, composite materials, substrates, sheets, films, optical elements, optical lenses, optical components, stereolithography, electronic paper, touch panels, solar cell substrates, optical waveguides, light guide plates, and holographic memory.

[0112] Furthermore, various composite materials obtained by blending the epoxy resin composition of this disclosure with various inorganic fillers, organic fillers, reinforcing fibers, etc., can also be used as the above-mentioned electrical and electronic materials.

[0113] Examples of inorganic fillers include calcium carbonate, magnesium carbonate, clay, kaolin, calcium phosphate, hydroxyapatite, mica, talc, silica, quartz powder, glass powder, diatomaceous earth, nepheline sinite, cristobalite, wollastonite, aluminum hydroxide, iron oxide, zinc oxide, titanium dioxide, alumina, calcium sulfate, barium sulfate, dolomite, silicon carbide, silicon nitride, boron nitride, metal powder, graphite, carbon black, silver hydroxyapatite, silver zeolite, etc. Examples of organic fillers include granular materials of various polymers such as cross-linked polymethyl methacrylate. These can be used individually or in combination of two or more.

[0114] Examples of reinforcing fibers include carbon fiber, glass fiber, aramid fiber, boron fiber, graphite fiber, silicon carbide fiber, high-strength polyethylene fiber, tungsten carbide fiber, and poly(p-phenylenebenzoxazole) fiber (PBO fiber). These can be used individually or in combination of two or more types.

[0115] Each aspect disclosed herein can be combined with any other features disclosed herein. [Examples]

[0116] The invention of this disclosure will be described in more detail below based on examples, but each configuration and combination thereof in each embodiment is merely an example, and additions, omissions, substitutions, and other modifications can be made as appropriate without departing from the spirit of the invention of this disclosure. This disclosure is not limited by the embodiments, but is limited only by the claims. The units of the blending amounts of each component of the epoxy resin composition in Table 1 are parts by weight.

[0117] Products 1 ¹H-NMR spectra were measured using a JNM-ECZ400S (manufactured by JEOL Ltd.), with deuterated chloroform as the solvent and at a temperature of 20°C.

[0118] Furthermore, the weight-average molecular weight (Mw) of the product was measured by gel permeation chromatography (GPC) using an HLC-8420GPC (manufactured by Tosoh Corporation), with THF as the solvent, measurement conditions at 40°C, flow rate of 0.350 mL / min, and molecular weight calculated on a standard polystyrene basis.

[0119] Comparative Example 1 [Manufacturing of epoxy resin using trimethylolpropane as an initiator] At room temperature under a nitrogen atmosphere, 50.0 g (0.373 mol) of trimethylolpropane [manufactured by Tokyo Chemical Industry Co., Ltd.], 694.2 g (5.59 mol) of 1,2-epoxy-4-vinylcyclohexane [manufactured by Daicel Corporation], and 282.3 g of ethyl acetate were added to a 2 L glass reactor and stirred. Next, the temperature was raised to 50°C and the trimethylolpropane was dissolved. After dissolution, 88.1 g (net weight: 13.2 g) of ethyl acetate solution (15%) of boron trifluoride diethyl ether complex [manufactured by Stella Chemifa Co., Ltd.] was added dropwise over 4 hours. After addition, the mixture was stirred for 1 hour to complete the reaction. Then the temperature was lowered to 45°C, and 387 g of ethyl acetate and 558 g of water were added and the mixture was washed with water. After washing with water, the organic layer was separated. 250 g of the separated organic layer (solid content concentration 51.31%) was heated to 60°C, and 277.6 g (1.06 mol) of ethyl acetate solution (29%) of peracetic acid was added dropwise over 2 hours under a nitrogen atmosphere. After addition, the mixture was stirred for 5 hours until the reaction was complete, then the temperature was lowered to 45°C and washed with water. The resulting organic layer was separated, and ethyl acetate was removed using an evaporator to obtain 140 g of the target product (EHPE3150). The softening point, measured according to the ring-and-sphere method of JIS K2207, was 76°C.

[0120] Example 1 [Manufacturing of epoxy resin using bisphenoxyethanol fluorene as an initiator] At room temperature under a nitrogen atmosphere, 30.0 g (0.068 mol) of bisphenoxyethanol fluorene [manufactured by Osaka Gas Chemical Co., Ltd.], 127.4 g (1.026 mol) of 1,2-epoxy-4-vinylcyclohexane [manufactured by Daicel Corporation], and 59.7 g of ethyl acetate were added to a 2 L glass reactor and stirred. Next, the temperature was raised to 50°C and the bisphenoxyethanol fluorene was dissolved. After dissolution, 16.2 g (net weight: 2.43 g) of ethyl acetate solution (15%) of boron trifluoride diethyl ether complex [manufactured by Stella Chemifa Co., Ltd.] was added dropwise over 1 hour. After addition, the mixture was stirred for 1 hour until the reaction was complete, then the temperature was lowered to 45°C, and 84.0 g of ethyl acetate and 118.1 g of water were added and washed with water. After washing with water, the organic layer was separated. 294.1 g of the separated organic layer was heated to 60°C, and 333.7 g (1.23 mol) of ethyl acetate solution (28%) of peracetic acid was added dropwise over 2 hours under a nitrogen atmosphere. After addition, the mixture was stirred for 5 hours until the reaction was complete, then the temperature was lowered to 45°C and washed with water. The resulting organic layer was separated, and ethyl acetate was removed using an evaporator to obtain 170 g of the target product (epoxy resin (1)). The softening point, measured according to the ring-and-sphere method of JIS K2207, was 82°C. The epoxy resin (1) obtained 1 The 1H-NMR spectrum is shown in Figure 1. Peaks attributed to the fluorene skeleton and phenyl group were observed at chemical shift (δ) 7.8–6.7 ppm (16H), and peaks attributed to the epoxy group were observed at 2.7 ppm (2H) and 2.5 ppm (1H). The weight-average molecular weight of epoxy resin (1), measured by GPC and converted to standard polystyrene, was 1256.

[0121] Example 2, Comparative Examples 2 and 3 According to the composition shown in Table 1, each epoxy resin and curing catalyst was mixed together, and the mixture was uniformly blended using a self-rotating stirring device (product name "Awatori Rentaro AR-250", manufactured by Shinky Co., Ltd.), and then degassed to obtain the epoxy resin composition. The epoxy resin composition obtained above was poured into a molding machine and cured by heating under the curing conditions shown in Table 1 to produce a cured product.

[0122] [evaluation] The epoxy resin compositions and cured products obtained in Example 2, Comparative Examples 2 and 3 were evaluated as follows.

[0123] [viscosity] The viscosity (mPa·s) of the epoxy resin compositions obtained in Example 2 and Comparative Examples 2 and 3 at 25°C was measured using an E-type viscometer (model "VISCOMETER TV-22", manufactured by Toki Sangyo Co., Ltd.). The results are shown in Table 1.

[0124] [Cure degree] The degree of curing (%) was measured using the epoxy resin compositions and cured products obtained in Example 2, Comparative Examples 2 and 3. The results are shown in Table 1. The degree of curing (%) was calculated by comparing the amount of heat generated before curing with the residual heat generated after curing, measured at a heating rate of 5°C / min using a differential scanning calorimetry device (DSC6200, manufactured by Hitachi High-Tech Science Corporation).

[0125] [Heat resistance (TMA)] The glass transition temperature (Tg(TMA)) of the cured products obtained in Example 2 and Comparative Examples 2 and 3 was determined using a TMA measuring device (TMA / SS100, manufactured by SII Nanotechnology Co., Ltd.) in accordance with JIS K7197. The thermal expansion coefficient was measured in a nitrogen atmosphere at a heating rate of 5°C / min within the measurement temperature range of 30 to 300°C. The glass transition point was then determined by drawing tangents to the curves before and after the measurement and finding the intersection of these tangents. The results are shown in Table 1. Furthermore, the coefficient of linear expansion of the cured products obtained in Example 2 and Comparative Examples 2 and 3 was determined by taking α1 as the slope of the straight line on the lower temperature side of the glass transition temperature and α2 as the slope of the straight line on the higher temperature side of the glass transition temperature. The results are shown in Table 1.

[0126] [Heat resistance (Tg-DTA)] The thermal decomposition temperature (5% weight loss temperature (T)) of the cured products obtained in Example 2, Comparative Examples 2 and 3 d5The temperature was measured using a differential thermogravimetric / thermogravimetric analyzer (TG / DTA) [manufactured by Seiko Instruments Inc.]. The measurement was performed by heating the sample from 25°C to 400°C at a heating rate of 10°C / min under nitrogen flow. The results are shown in Table 1.

[0127] [Bendability] Using the cured materials (4 mm thick x 10 mm wide x 80 mm long) obtained in Example 2 and Comparative Examples 2 and 3 as samples, a three-point bending test was performed using a Tensilon universal testing machine (manufactured by Orientec Co., Ltd.) under the conditions of edge span: 67 mm and bending speed: 2 mm / min. The bending strength, bending modulus of elasticity, and bending elongation of the cured materials were measured. The results are shown in Table 1.

[0128] [Table 1]

[0129] Compared to Comparative Example 2, which did not contain epoxy resin (1), and Comparative Example 3, which contained 45 parts by weight of EHPE3150 instead of epoxy resin (1), Example 2 showed an increased glass transition temperature (Tg), no decrease in flexural modulus, and a significant improvement in flexural strength and flexural elongation (especially flexural elongation). As described above, it can be seen that the epoxy resin composition containing the epoxy resin of this disclosure provides a cured product that exhibits superior heat resistance and / or mechanical properties compared to the comparative epoxy resin composition containing EHPE3150.

[0130] The components listed in Table 1 are as follows: [Epoxy compounds] Celoxide 2021P: Product name "Celoxide 2021P" (3,4-epoxycyclohexylmethyl(3,4-epoxy)cyclohexanecarboxylate, manufactured by Daicel Corporation) EHPE3150: Epoxy resin produced in Comparative Example 1 Epoxy resin (1): Epoxy resin produced in Example 1 [Curing catalyst] SI-100L: Product name "San-Aid SI-100L" (manufactured by Sanshin Chemical Industry Co., Ltd.)

Claims

1. It contains the following epoxy resin and epoxy compound, An epoxy resin composition in which the content of the epoxy compound is 55% by weight or more and less than 70% by weight relative to the total of the epoxy resin and the epoxy compound. Epoxy resin: An epoxy resin represented by the following formula (1), with a weight-average molecular weight of 1,000 to 10,000 on a standard polystyrene basis. 【Chemistry 1】 [In formula (1), ring A represents an aromatic hydrocarbon ring, either identical or different. R １ R represents a cyano group, a halogen atom, or an alkyl group, either identical or different. ２ is the same or different, representing a hydrocarbon group, alkoxy group, cycloalkoxy group, aryloxy group, aralkyloxy group, alkylthio group, cycloalkylthio group, arylthio group, aralkylthio group, acyl group, alkoxycarbonyl group, hydroxyl group, halogen atom, nitro group, cyano group, or substituted amino group. j is the same or different, representing an integer from 0 to 4. k is the same or different, representing an integer of 0 or more. R ３ This indicates a group that is the same or different and is represented by the following formula (1-1). 【Chemistry 2】 [In formula (1-1), R ４ R represents an alkylene group with 2 to 4 carbon atoms. ５ R represents an alkylene group with 3 to 6 carbon atoms. ６ The formula is (1a) below 【Transformation 3】 This shows the base represented by . x represents 1. y represents 0. z represents an integer from 3 to 10. Epoxy compounds: Compounds represented by the following formula (I). 【Chemistry 4】 [In formula (I), X represents a single bond or a linking group (a divalent group having one or more atoms).]

2. The epoxy resin composition according to claim 1, wherein ring A in formula (1) is a benzene ring.

3. Furthermore, the epoxy resin composition according to claim 1 or 2 further contains a curing agent and a curing accelerator.

4. Furthermore, the epoxy resin composition according to claim 1 or 2 further contains a curing catalyst.

5. The epoxy resin composition according to any one of claims 1 to 4, which is a composite resin composition.

6. A cured product of the epoxy resin composition according to any one of claims 1 to 5.

7. An electronic product comprising the cured product described in claim 6.

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