Epoxy resin composition and epoxy resin cured product

Abstract

To provide an epoxy resin composition capable of suppressing cracks and peeling due to thermal stress while suppressing deterioration of the mechanical and thermal properties inherent to epoxy resins.SOLUTION: According to the present invention, an epoxy resin composition including 100 pts.mass of an epoxy resin (A), 5-90 pts.mass of a compound (B) represented by formula (1), and 10-90 pts.mass of a curing agent (C) is provided.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an epoxy resin composition and a cured epoxy resin product. [Background technology]

[0002] Epoxy resins have been used in the fields of molding materials, adhesive materials, electronic parts, ink materials, etc., because of their excellent moldability, electrical properties, moisture resistance, heat resistance, mechanical properties, etc. Epoxy resins are also used as sealing materials for electronic part elements such as semiconductor devices.

[0003] For example, epoxy resin cured products used as sealing materials are required to be free from cracks and peeling caused by stresses such as thermal expansion and contraction, etc. In order to suppress cracks and peeling caused by thermal stress, the incorporation of various additives into epoxy resins has been considered (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2003-183348 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, there was a problem that the mechanical and thermal properties inherent to the epoxy resin were impaired by the incorporation of additives.

[0006] The present invention has been made in consideration of the above circumstances, and provides an epoxy resin composition that can suppress cracking and peeling due to thermal stress while suppressing deterioration of the mechanical properties and thermal properties inherent to epoxy resins. [Means for solving the problem]

[0007] According to the present invention, there is provided an epoxy resin composition comprising 100 parts by mass of an epoxy resin (A), 5 to 90 parts by mass of a compound (B) represented by the following formula (1), and 10 to 90 parts by mass of a curing agent (C).

[0008] As a result of extensive investigations, the present inventors have found that the above problems can be solved by using the above composition, which has led to the completion of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described in detail.

[0010] 1. Composition of epoxy resin composition An epoxy resin composition according to one embodiment of the present invention contains an epoxy resin (A), a compound (B), and a curing agent (C).

[0011] 1-1.Epoxy resin (A) The epoxy resin (A) means a compound other than the compound (B) having a plurality of epoxy groups (preferably a plurality of glycidyl groups). The number of epoxy groups in one molecule of the epoxy resin (A) is, for example, 2, 3, or 4, preferably 2 or 3, and more preferably 2. The epoxy equivalent of the epoxy resin (A) is, for example, 120 to 400 (g / eq), specifically, for example, 120, 140, 160, 180, 200, 220, 240, 260, 280, or 300 (g / eq), and may be within a range between any two of the numerical values ​​exemplified here. The epoxy equivalent can be measured according to JIS K 7236:2009.

[0012] From the viewpoint of handling, the epoxy resin (A) is preferably liquid at 25° C. The weight average molecular weight (Mw) of the epoxy resin (A) is, for example, 240 to 600, specifically, for example, 240, 280, 320, 360, 400, 440, 480, 520, 560, or 600, and may be within a range between any two of the numerical values ​​exemplified here. Mw can be measured by gel permeation chromatography (GPC).

[0013] It is preferable that the epoxy resin (A) does not have a reactive functional group selected from an amino group, a carboxy group, a phenolic hydroxyl group, and a thiol group, and is not a carboxylic acid anhydride. Such reactive functional groups are highly reactive with epoxy groups, and therefore react with the epoxy groups contained in the compound (B) to form bonds between the epoxy resin (A) and the compound (B), which tends to deteriorate the inherent mechanical and thermal properties of the epoxy resin.

[0014] In the epoxy resin composition of the present embodiment, it is assumed that the epoxy resin (A) and the compound (B) are bonded via the curing agent (C), and it is preferable that the epoxy resin (A) and the compound (B) do not react directly with each other. For example, it is preferable that the epoxy resin (A) and the compound (B) do not cure when heated at 120°C for 3 hours in the coexistence of the epoxy resin (A) and the compound (B) in the absence of the curing agent (C).

[0015] It is preferable that the epoxy resin (A) does not have an addition reaction moiety (hereinafter, "DA reaction addition moiety") formed by the Diels-Alder reaction of a conjugated diene structure and a dienophile structure, because such an addition reaction moiety is likely to deteriorate the inherent mechanical properties and thermal properties of the epoxy resin.

[0016] Examples of the epoxy resin (A) include bifunctional or crystalline epoxy resins such as biphenyl-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, stilbene-type epoxy resins, and hydroquinone-type epoxy resins; novolac-type epoxy resins such as cresol novolac-type epoxy resins, phenol novolac-type epoxy resins, and naphthol novolac-type epoxy resins; phenol aralkyl-type epoxy resins such as phenylene skeleton-containing phenol aralkyl-type epoxy resins, biphenylene skeleton-containing phenol aralkyl-type epoxy resins, and phenylene skeleton-containing naphthol aralkyl-type epoxy resins; and trifunctional epoxy resins such as triphenol methane-type epoxy resins and alkyl-modified triphenol methane-type epoxy resins. Of these, biphenyl-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, cresol novolac-type epoxy resins, and biphenylene skeleton-containing phenol aralkyl-type epoxy resins are particularly preferred.

[0017] Commercially available examples of epoxy resin (A) are as follows: Biphenyl type epoxy resin: YX4000 (Mitsubishi Chemical) Bisphenol A epoxy resin: jER-828 (Mitsubishi Chemical) Bisphenol F type epoxy resin: EPICLON 830 (DIC) · Cresol novolac epoxy resin: EPICLON N-680 (DIC) Biphenylene skeleton-containing phenol aralkyl type epoxy resin: NC3000 (Nippon Kayaku)

[0018] 1-2. Compound (B) Compound (B) is a compound represented by the following formula (1). Compound (B) has a DA reaction adduct moiety. The DA reaction adduct moiety dissociates when the epoxy resin cured material is exposed to high temperatures, thereby relieving the stress of the epoxy resin cured material and suppressing the occurrence of cracks and peeling in the epoxy resin cured material.

[0019] The content of the compound (B) relative to 100 parts by mass of the epoxy resin (A) is 5 to 90 parts by mass, preferably 5 to 80 parts by mass, and more preferably 5 to 60 parts by mass. If the content of the compound (B) is too small, the effect of stress relaxation is not fully exerted. If the content of the compound (B) is too large, the deterioration of mechanical properties and thermal properties tends to become significant. Specifically, this content is, for example, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or 90 parts by mass, and may be within a range between any two of the numerical values ​​exemplified here.

[0020] [ka] (In formula (1), R 1 teeth,* 2 -(CH2) a -X-(CH2) b -* 1 , or * 2 -Ar 1 -(CH2) a -X-(CH2) b -* 1 and * 1 is the bond with the epoxy group, and * 2 is the bond to another group, X is -O-, -S-, -NR 2 - or -COO-, R 2 is -CH3, -C2H5, or -(CH2) a There is a group represented by -CH(O)CH2, Ar 1 is an unsubstituted phenyl group or a phenyl group substituted with 1 to 4 (e.g., 1, 2, 3, 4) methyl or ethyl groups, a is an integer from 0 to 5 (e.g., 0, 1, 2, 3, 4, 5), b is an integer from 1 to 5 (e.g., 1, 2, 3, 4, 5), Y is a direct bond or a group represented by formula (2), and * in formula (2) 3 and* 4 are R 1 and the bond with N.) [ka] (In formula (2), R 3 is -(CH2) d -, -[(CH2) d -O] e -(CH2) d -, -Ar 2 - or -Ar 3 -R 4 -Ar 3 - and d is an integer from 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, 8), e is an integer from 1 to 3 (e.g., 1, 2, 3), Ar 2 and Ar 3 are respectively an unsubstituted phenyl group, a phenyl group substituted with 1 to 4 (e.g., 1, 2, 3, 4) methyl or ethyl groups, an unsubstituted biphenyl group, and a biphenyl group substituted with 1 to 8 (e.g., 1, 2, 3, 4, 5, 6, 7, 8) methyl or ethyl groups, R 4 is -(CH2) f -, -O-, -S-, -SO-, -SO2-, -CO-, or -[(CH2) f -O] g -(CH2) f - is a group represented by f is an integer between 1 and 8 (e.g. 1, 2, 3, 4, 5, 6, 7, 8), and g is an integer between 1 and 3 (e.g. 1, 2, 3).

[0021] Y in formula (1) is preferably a group represented by formula (2). In this case, since compound (B) has two DA reaction adducts, the effect of stress relaxation is remarkable. 3 -Ar 3 -R 4 -Ar 3 - is preferred.

[0022] Compound (B) can be obtained, for example, by subjecting a conjugated diene compound represented by formula (3) and a dienophile compound represented by formula (4) or formula (5) to a Diels-Alder reaction.

[0023] [ka]

[0024] [ka]

[0025] [ka]

[0026] The dissociation starting temperature of the compound (B) is preferably 80 to 190°C. The dissociation starting temperature is the temperature at which the dissociation of the DA addition reaction part of the compound (B) starts, and can be measured by the method described in "3. Evaluation of the epoxy resin composition" described later. If the dissociation starting temperature is too low, the mechanical properties and thermal properties are likely to deteriorate, and if the dissociation starting temperature is too high, the DA addition reaction part of the compound (B) is not dissociated during a normal thermal cycle, and the effect of stress relaxation is difficult to be exhibited. The dissociation starting temperature is specifically, for example, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, or 190°C, and may be within a range between any two of the numerical values ​​exemplified here.

[0027] Compound (B) does not have a reactive functional group selected from an amino group, a carboxy group, a phenolic hydroxyl group, and a thiol group, and is not a carboxylic acid anhydride, and therefore does not react with the epoxy groups of epoxy resin (A).

[0028] 1-3. Hardener (C) The curing agent (C) is a compound capable of reacting with a plurality of epoxy groups to link compounds having epoxy groups together. The curing agent (C) preferably has a plurality of reactive functional groups selected from amino groups, carboxy groups, phenolic hydroxyl groups, and thiol groups, or is a carboxylic anhydride. The curing agent (C) links epoxy resins (A) together, compounds (B) together, or epoxy resins (A) and compounds (B) together to form a high molecular weight compound, thereby curing the epoxy resin composition to form a cured epoxy resin.

[0029] The content of the curing agent (C) relative to 100 parts by mass of the epoxy resin (A) is 10 to 90 parts by mass, preferably 20 to 85 parts by mass, and more preferably 30 to 80 parts by mass. If the amount of the curing agent (C) is too small or too large, the mechanical properties and thermal properties of the epoxy resin cured product tend to deteriorate. Specifically, the content is, for example, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, or 90 parts by mass, and may be within a range between any two of the numerical values ​​exemplified here.

[0030] In particular, from the viewpoint of not significantly changing the various physical properties of the epoxy resin (A) even when compound (B) is blended, it is preferable that the curing agent (C) is contained in the composition so that the total value of the epoxy equivalents of the epoxy resin (A) and the compound (B) is close to the functional group equivalent of the curing agent (C). The value of {functional group equivalent of the curing agent (C)} / {total value of the epoxy equivalents of the epoxy resin (A) and the compound (B)} is, for example, 0.8 to 1.2, specifically, for example, 0.8, 0.9, 1.0, 1.1, 1.2, and may be within the range between any two of the numerical values ​​exemplified here.

[0031] The epoxy resin cured product obtained by curing the epoxy resin composition containing the epoxy resin (A), compound (B) and curing agent (C) in the above-mentioned ratio suppresses deterioration of the mechanical properties and thermal properties inherent to the epoxy resin, while suppressing cracking and peeling due to thermal stress.

[0032] The curing agent (C) is preferably at least one selected from an amine-based curing agent, a phenol-based curing agent, an acid anhydride-based curing agent, and a polyvalent carboxylic acid compound.

[0033] (Amine-based hardener) Examples of the amine-based curing agent include one or more selected from the group consisting of aliphatic polyamines such as diethylenetriamine (DETA), triethylenetetramine (TETA), and metaxylylenediamine (MXDA); aromatic polyamines such as diaminodiphenylmethane (DDM), m-phenylenediamine (MPDA), and diaminodiphenylsulfone (DDS); and polyamine compounds such as dicyandiamide (DICY) and organic acid dihydralazide. As the amine-based curing agent, aliphatic polyamines are particularly preferred.

[0034] Examples of commercially available amine-based curing agents are as follows: Aliphatic polyamines: jER Cure ST12 (Mitsubishi Chemical), Adeka Hardener EH-6019 (ADEKA)

[0035] (Phenol-based hardener) Examples of phenol-based curing agents include novolac resins obtained by condensing or co-condensing phenols such as phenol novolac resins and cresol novolac resins with formaldehyde or ketones under an acid catalyst; phenol aralkyl resins having a phenylene skeleton synthesized from the above-mentioned phenols and dimethoxyparaxylene or bis(methoxymethyl)biphenyl; phenol aralkyl resins such as phenol aralkyl resins having a biphenylene skeleton; and phenol resins having a trisphenylmethane skeleton. The phenol-based curing agent preferably contains one or more resins selected from the group consisting of biphenyl aralkyl type phenol resins and triphenylmethane type phenol resins.

[0036] As the phenol-based hardener, cresol novolac resin and phenol aralkyl resin having a biphenylene skeleton are particularly preferred.

[0037] Examples of commercially available phenolic hardeners are as follows: Cresol novolac type: PHENOLITE TD-2131 (DIC) Biphenyl aralkyl type: KAYAHARD GPH-65 (Nippon Kayaku)

[0038] (Acid anhydride curing agent) Examples of the acid anhydride curing agent include one or more selected from the group consisting of alicyclic acid anhydrides such as hexahydrophthalic anhydride (HHPA), methyltetrahydrophthalic anhydride (MTHPA), and maleic anhydride; and aromatic acid anhydrides such as trimellitic anhydride (TMA), pyromellitic anhydride (PMDA), benzophenonetetracarboxylic acid (BTDA), and phthalic anhydride.

[0039] (Polycarboxylic acid compound) Examples of polyvalent carboxylic acid compounds include phthalic acid, hydroxyisophthalic acid, succinic acid, sebacic acid, maleic acid, dodecenylsuccinic acid, chlorendic acid, pyromellitic acid, trimellitic acid, hexahydrophthalic acid, methylhexahydrophthalic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, and methylnadic acid.

[0040] 1-4.Curing catalyst The epoxy resin composition of the present invention may contain a curing catalyst. By containing a curing catalyst, the curing time of the epoxy resin composition can be shortened. The content of the curing catalyst relative to 100 parts by mass of the epoxy resin (A) is 0.1 to 5 parts by mass, preferably 0.3 to 4.5 parts by mass, and more preferably 0.5 to 4.0 parts by mass. Specifically, the content is, for example, 0.1, 0.3, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, or 5.0 parts by mass, and may be within a range between any two of the numerical values ​​exemplified here.

[0041] Examples of the curing catalyst include 1,8-diazabicyclo[5.4.0]undecene-7 (DBU) or a salt thereof; 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) or a salt thereof; tertiary amines such as benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and N,N-dimethylcyclohexylamine; and phosphines such as triphenylphosphine and tris(dimethoxy)phosphine.

[0042] 1-5.Additives The epoxy resin composition of the present invention may contain at least one additive selected from ultraviolet absorbers, antioxidants, preservatives, rust inhibitors, pigments, tackifiers, surface lubricants, gloss agents, water repellents, photosensitizers, organic and inorganic fibers, plasticizers, conductive fillers, inorganic fillers, flame retardants, antistatic agents, foam stabilizers, mold release agents, colorants, and foaming agents, as necessary. The additives may be used alone or in combination of two or more. The content of the additive relative to 100 parts by mass of the epoxy resin (A) is, for example, 0 to 50 parts by mass, and more preferably 0 to 20 parts by mass. Specifically, the content may be, for example, 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50 parts by mass, and may be within a range between any two of the numerical values ​​exemplified here.

[0043] 1-6.Solvent The epoxy resin composition of the present invention may contain a solvent. Examples of the solvent include aromatic hydrocarbons such as benzene, toluene, and xylene; aliphatic hydrocarbons such as n-pentane, n-hexane, n-heptane, and n-octane; alicyclic hydrocarbons such as cyclopentane, cyclohexane, cycloheptane, and cyclooctane; ethers such as diethyl ether, diisopropyl ether, 1,2-dimethoxyethane, dibutyl ether, tetrahydrofuran, dioxane, anisole, phenylethyl ether, and diphenyl ether; halogenated hydrocarbons such as chloroform, carbon tetrachloride, 1,2-dichloroethane, and chlorobenzene; esters such as ethyl acetate, propyl acetate, butyl acetate, and methyl propionate; ketones such as acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, and cyclohexanone; amides such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone; nitriles such as acetonitrile and benzonitrile; and sulfoxides such as dimethyl sulfoxide and sulfolane. The solvent may be used alone or in combination of two or more kinds.

[0044] The content of the solvent in the epoxy resin composition of the present invention is usually 70% by mass or less, preferably 30% by mass or less, and more preferably 20% by mass or less.

[0045] 2. Method of using the epoxy resin composition The epoxy resin composition of the present invention can be cured to form an epoxy resin cured product. In one example, the epoxy resin composition can be cured by heating or irradiating with light.

[0046] In the case of thermal curing, the heating temperature during curing (curing temperature) is usually 20 to 300°C, preferably 40 to 250°C, and more preferably 60 to 200°C. Specifically, the curing temperature is, for example, 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220, 240, 250, 260, 280, or 300°C, and may be within a range between any two of the numerical values ​​exemplified here. The heating time during curing (curing time) is usually 10 to 1440 minutes, preferably 30 to 900 minutes, and more preferably 60 to 480 minutes. The heating can also be performed in multiple stages.

[0047] In the case of photocuring, examples of light include ultraviolet light, visible light, and infrared light, and ultraviolet light is preferred. The exposure dose is preferably 1 to 10,000 mJ / cm. 2 , more preferably 10 to 3000 mJ / cm 2 Examples of light sources include low pressure mercury lamps, high pressure mercury lamps, extra high pressure mercury lamps, carbon arc lamps, xenon lamps, metal halide lamps, chemical lamps, black light fluorescent lamps, and electrodeless UV lamps.

[0048] The curing reaction can be carried out by coating the epoxy resin composition of the present invention on a substrate, or by pouring the composition into a mold.

[0049] The shape of the cured product of the present invention is not particularly limited, and examples thereof include a plate, a sheet, and a film. The thickness of these is, for example, usually 0.01 to 1000 mm, preferably 0.1 to 100 mm, and more preferably 0.1 to 5 mm.

[0050] The epoxy resin composition may be of one-component type or two-component type. In the case of the two-component type, it is preferable that the first component contains the epoxy resin (A) and the compound (B), and the second component contains the curing agent (C). In this case, the curing agent (C) does not react with the epoxy resin (A) or the compound (B) during storage, so that the storage stability is improved. During use, the first component and the second component are mixed to cause the curing agent (C) to react with the epoxy resin (A) and the compound (B).

[0051] By using the epoxy resin composition of the present invention, it is possible to form a cured epoxy resin product in which deterioration of the mechanical properties and thermal properties inherent to the epoxy resin is suppressed, while cracking and peeling due to thermal stress are suppressed.

[0052] Since the epoxy resin composition of the present invention has the above-mentioned properties, it can be used for applications such as electronic materials, binders, coating materials, adhesives, etc. Specific examples of the epoxy resin composition include substrates for electronic components such as semiconductor packages, build-up films, solder resist inks, underfill materials, solid sealing materials for packages, binders for paving, binders for carbon fiber reinforced plastics (CFRP), cationic electrodeposition coating agents, heavy-duty anticorrosive coatings, powder coatings, adhesives for infrastructure repair / reinforcement, and general household / industrial adhesives. The epoxy resin composition of the present invention is suitable for these applications. EXAMPLES

[0053] 1. Preparation of compound (B) 1-1. Manufacturing Example 1 In a reaction apparatus equipped with a stirrer, reflux condenser, thermometer, and nitrogen inlet tube, 66.4 g (0.15 mol) of 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide (BMI-5100: manufactured by Daiwa Kasei Kogyo Co., Ltd.) and 92.5 g (0.60 mol) of furfuryl glycidyl ether were charged, and the temperature was raised to 80°C while introducing nitrogen gas, and then the mixture was stirred for 2 hours. After cooling to room temperature, the mixture was diluted with a mixed solvent of ethyl acetate:hexane = 3:1, and then purified by silica gel chromatography to obtain compound (B1) represented by formula (6).

[0054] [ka]

[0055] 1-2. Manufacturing Example 2 Compound (B2) represented by formula (7) was obtained in the same manner as in Production Example 1, except that 40.2 g (0.15 mol) of m-phenylene bismaleimide (BMI-3000: manufactured by Daiwa Chemical Industry Co., Ltd.) was used instead of 0.15 mol of 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide.

[0056] [ka]

[0057] 1-3. Manufacturing Example 3 Compound (B3) represented by formula (8) was obtained in the same manner as in Production Example 1, except that 33.0 g (0.15 mol) of 1,2-bis(maleimido)ethane was used instead of 0.15 mol of 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide.

[0058] [ka]

[0059] 1-4. Manufacturing Example 4 18.9g (0.10mol) of 4-hydroxyphenylmaleimide, 3.22g (0.01mol) of tetrabutylammonium bromide, 80g of 40% by mass sodium hydroxide aqueous solution, and 80g of toluene were charged into a reactor equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen inlet tube, and the temperature was raised to 60°C while introducing nitrogen gas, and 46.3g (0.50mol) of epichlorohydrin was added dropwise, and the mixture was stirred for 2 hours. After the reaction was completed, the aqueous layer was separated, and the organic layer was washed three times with ion-exchanged water, dried with magnesium sulfate, and then concentrated. Next, 30.8g (0.20mol) of the concentrated residue and furfuryl glycidyl ether were charged into a reactor equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen inlet tube, and the temperature was raised to 80°C while introducing nitrogen gas, and then the mixture was stirred for 2 hours. After cooling to room temperature, the mixture was diluted with a mixed solvent of ethyl acetate:hexane=3:1, and then purified by silica gel chromatography to obtain compound (B4) represented by formula (9).

[0060] [ka]

[0061] 1-5. Manufacturing Example 5 Comparative compound 1 represented by formula (10) was obtained in the same manner as in Production Example 1, except that 58.9 g (0.60 mol) of furfuryl alcohol was used instead of 0.60 mol of furfuryl glycidyl ether.

[0062] [ka]

[0063] 1-6. Manufacturing Example 6 50.0g (0.24mol) of 9-(hydroxymethyl)anthracene, 7.74g (0.024mol) of tetrabutylammonium bromide, 200g of 40% by mass aqueous sodium hydroxide solution, and 200g of toluene were charged into a reaction apparatus equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen inlet tube, and the temperature was raised to 60°C while introducing nitrogen gas, and 111.1g (1.2mol) of epichlorohydrin was added dropwise, followed by stirring for 2 hours. After the reaction was completed, the aqueous layer was separated, and the organic layer was washed three times with ion-exchanged water, dried over magnesium sulfate, and then concentrated. Next, the concentrated residue and 26.6 g (0.06 mol) of 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide (BMI-5100: manufactured by Daiwa Kasei Kogyo Co., Ltd.) were charged into a reaction apparatus equipped with a stirrer, a reflux condenser, a thermometer, and a nitrogen inlet tube, and the temperature was raised to 180°C while introducing nitrogen gas, and then the mixture was stirred for 2 hours. After cooling to room temperature, the mixture was diluted with ethyl acetate and purified by silica gel chromatography to obtain comparative compound 2 represented by formula (11).

[0064] [ka]

[0065] 2. Preparation of epoxy resin composition 2-1. Example 1 100 parts by mass of epoxy resin (A) (jER-828: manufactured by Mitsubishi Chemical) and 10 parts by mass of compound (B1) were placed in a container and left for 1 hour in an 80°C environment. Then, jER-828 and compound (B1) were mixed using a glass rod and left until the temperature of the mixture reached 25°C. Then, the mixture of jER-828 and compound (B1) was mixed with 52 parts by mass of curing agent (C) (ST-12: manufactured by DIC) in a mixer (ARE-310: manufactured by Thinky) for 2 minutes to obtain an epoxy resin composition.

[0066] 2-2. Examples 2 to 9, Comparative Examples 1 to 3, and Reference Examples 1 to 3 The epoxy resin compositions of Examples 2 to 9, Comparative Examples 1 to 3, and Reference Examples 1 to 3 were obtained in the same manner as in Example 1, except that the blending compositions were changed as shown in Tables 1 and 2. In Example 5 and Reference Example 2, the curing agent (C) was heated at 80° C. for 30 minutes before being charged into the mixer.

[0067] [Table 1]

[0068] [Table 2]

[0069] Details of the components in the table are as follows: jER-828: Bisphenol A type epoxy resin; manufactured by Mitsubishi Chemical EPICLON830: Bisphenol F type epoxy resin; manufactured by DIC ST12: Aliphatic polyamine curing agent (jER Cure ST12); manufactured by Mitsubishi Chemical TD-2131: Cresol novolac type hardener (PHENOLITETD-2131); manufactured by DIC PPh3: Triphenylphosphine

[0070] 3. Evaluation of epoxy resin composition Various evaluations were carried out on the epoxy resin compositions of Examples, Comparative Examples, and Reference Examples. The results are shown in Tables 1 and 2.

[0071] As shown in Tables 1 and 2, the Examples had higher glass transition temperatures than the Comparative Examples, and had values ​​close to those of the Reference Examples not containing compound (B). The Examples also had comparable tensile modulus, maximum tensile stress, shear adhesive strength, and storage modulus to the Reference Examples. Furthermore, the Examples had better results in the thermal cycle test than the Reference Examples. From the above, it was found that the Examples of the present invention can suppress cracking and peeling due to thermal stress while suppressing deterioration of the inherent mechanical properties and thermal properties of epoxy resins.

[0072] The details of the evaluation are as follows: [Glass transition temperature / dissociation onset temperature] The epoxy resin composition to be evaluated was poured into a mold treated with a fluorine-based mold release agent, heated at 80°C for 3 hours, and then heated and cured at 120°C for a further 3 hours to prepare dumbbell test pieces.

[0073] The test piece was sealed in a simple sealed pan, and the temperature was raised from 30°C to 200°C at a rate of 10°C / min under a nitrogen stream using a differential scanning calorimeter (DSC), and the heat change was measured. A graph of "endothermic heat amount" vs. "temperature" was drawn, and the characteristic inflection observed at this time was taken as the glass transition. The glass transition temperature was a value obtained from the DSC curve by the midpoint method. The dissociation onset temperature was the extrapolated onset temperature of the endothermic peak that appeared at a temperature higher than the glass transition temperature.

[0074] [Tensile modulus of elasticity / maximum tensile stress] The epoxy resin composition to be evaluated was poured into a mold treated with a fluorine-based mold release agent, heated at 80°C for 3 hours, and then heated and cured at 120°C for a further 3 hours to prepare dumbbell test pieces.

[0075] The obtained test pieces were subjected to measurement of tensile modulus and maximum tensile stress under the following conditions in accordance with JIS-K7161. Sample size: Dumbbell size 1BA Test speed: 1.0mm / min ·Measurement environment: temperature 25℃ Number of measurements: 3 times, average value calculated

[0076] [Shear adhesive strength] The epoxy resin composition to be evaluated was applied to a SUS plate having a width of 25 mm, a length of 100 mm, and a thickness of 1.0 mm to obtain a SUS plate coated with a curable composition. Then, another SUS plate having a width of 25 mm, a length of 100 mm, and a thickness of 1.0 mm was attached to the side of the SUS plate coated with the epoxy resin composition, to which the curable composition was applied, so that the pasting area was 25 mm x 12.5 mm and the thickness of the cured product was 0.20 mm, and the plate was fixed with a clip. Then, the plate was heated at 80°C for 3 hours, and then heated at 120°C for 3 hours to obtain a test piece. The shear adhesive strength of the obtained test piece was measured according to JIS K 6850:1999 using a universal tensile tester (tensile speed 2.0 mm / min., test environment temperature 25°C).

[0077] [Storage modulus] The epoxy resin composition to be evaluated was poured into a mold treated with a fluorine-based mold release agent, heated at 80°C for 3 hours, and then heat-cured at 120°C for another 3 hours to prepare a test piece having a length of 5.0 cm, a width of 1.0 cm, and a thickness of 1.0 mm. The storage modulus of the obtained test piece was measured under the following conditions using a dynamic viscoelasticity measuring device RSA3 (manufactured by TA Instruments). The storage modulus value shown in the table is the storage modulus value at 200°C. Heating rate: 5℃ / min Frequency: 1.0Hz Measurement temperature range: 30~300℃

[0078] [Cold-heat cycle test] The epoxy resin composition to be evaluated was applied to a SUS plate having a width of 25 mm, a length of 100 mm, and a thickness of 1.0 mm to obtain a SUS plate coated with a curable composition. Then, another SUS plate having a width of 25 mm, a length of 100 mm, and a thickness of 1.0 mm was attached to the side of the SUS plate coated with the epoxy resin composition so that the area of ​​attachment was 25 mm x 12.5 mm and the thickness of the cured product was 0.20 mm, and the plate was fixed with a clip. Then, the plate was heated at 80°C for 3 hours, and then heated at 120°C for 3 hours to obtain a test piece. The obtained test piece was left in a 25°C environment for 24 hours, and the test piece was visually checked for peeling after 150 cycles of -40°C x 30 minutes and 200°C x 30 minutes were repeated using a thermal shock device TSA-71L-A (manufactured by Espec). The test was performed three times for the same curable composition, and the numbers in the table indicate the number of times peeling occurred.

Claims

1. 100 parts by mass of epoxy resin (A); A compound (B) represented by the following formula (1) in an amount of 5 to 90 parts by mass, 10 to 90 parts by mass of a curing agent (C); 1. An epoxy resin composition comprising: 【Chemistry 1】 (In formula (1), R １ teeth,* ２ - (CH ２ ) ａ -X-(CH ２ ) ｂ -* １ , or * ２ -Ar １ - (CH ２ ) ａ -X-(CH ２ ) ｂ -* １ and * １ is the bond with the epoxy group, and * ２ is the bond to another group, X is -O-, -S-, -NR ２ is a group represented by - or -COO-, and R ２ is -CH ３ , -C ２ H ５ , or -(CH ２ ) ａ -CH(O)CH ２ There is a group represented by Ar １ is an unsubstituted phenyl group or a phenyl group substituted with one to four methyl or ethyl groups, a is an integer from 0 to 5, b is an integer from 1 to 5, Y is a direct bond or a group represented by formula (2), ３ and * ４ are R １ and the bond with N. 【Chemistry 2】 (In formula (2), R ３ is -(CH ２ ) ｄ -, - [(CH ２ ) ｄ -O] ｅ - (CH ２ ) ｄ -, -Ar ２ - or -Ar ３ -R ４ -Ar ３ - and d is an integer from 1 to 8, e is an integer from 1 to 3, Ar ２ and Ar ３ are respectively an unsubstituted phenyl group, a phenyl group substituted with 1 to 4 methyl or ethyl groups, an unsubstituted biphenyl group, or a biphenyl group substituted with 1 to 8 methyl or ethyl groups, R ４ is -(CH ２ ) ｆ -, -O-, -S-, -SO-, -SO ２ -, -CO-, or -[(CH ２ ) ｆ -O] ｇ - (CH ２ ) ｆ - is a group represented by f is an integer from 1 to 8, and g is an integer from 1 to 3.

2. 2. The epoxy resin composition according to claim 1, An epoxy resin composition, wherein Y in the formula (1) is a group represented by formula (2).

3. The epoxy resin composition according to claim 2, R in the above formula (2) ３ is -Ar ３ -R ４ -Ar ３ - Epoxy resin composition.

4. The epoxy resin composition according to any one of claims 1 to 3, The epoxy resin composition, wherein the curing agent is at least one selected from an amine-based curing agent, a phenol-based curing agent, an acid anhydride-based curing agent, and a polycarboxylic acid compound.

5. The epoxy resin composition according to any one of claims 1 to 4, The epoxy resin composition comprises 5 to 80 parts by mass of the compound (B) relative to 100 parts by mass of the epoxy resin (A).

6. 6. An epoxy resin cured product obtained by curing the epoxy resin composition according to claim 1.

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