Epoxy resin composition, 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 components, ink materials, etc., because of their excellent moldability, electrical properties, moisture resistance, heat resistance, mechanical properties, etc. Epoxy resins are also used as encapsulating materials for electronic component elements such as semiconductor devices.

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

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-183348 Summary of the Invention [Problem to be solved by the invention]

[0005] However, there was a problem that the intrinsic mechanical and thermal properties of epoxy resins were impaired by the addition of additives.

[0006] The present invention has been made in view 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 research, the present inventors have found that the above problems can be solved by using the above composition, and have thus completed the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments 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) refers to a compound other than the compound (B) that has multiple epoxy groups (preferably multiple 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 values ​​exemplified here. The epoxy equivalent can be measured according to JIS K 7236:2009.

[0012] From the viewpoint of ease 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 this 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 presence 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 referred to as "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 tends to deteriorate the mechanical and thermal properties inherent to the epoxy resin.

[0016] Preferred 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 triphenolmethane-type epoxy resins and alkyl-modified triphenolmethane-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] Examples of commercially available epoxy resins (A) are as follows: Biphenyl type epoxy resin: YX4000 (Mitsubishi Chemical) Bisphenol A epoxy resin: jER-828 (Mitsubishi Chemical) Bisphenol F epoxy resin: EPICLON 830 (DIC) Cresol novolac epoxy resin: EPICLON N-680 (DIC) Biphenylene skeleton-containing phenol aralkyl 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 addition reaction moiety dissociates when the cured epoxy resin material is exposed to high temperatures, thereby alleviating stress in the cured epoxy resin material and suppressing the occurrence of cracks and peeling in the cured epoxy resin material.

[0019] The content of compound (B) per 100 parts by mass of 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 compound (B) is too low, the stress relaxation effect is not fully exerted. If the content of compound (B) is too high, the mechanical properties and thermal properties tend to deteriorate significantly. Specific examples of this content include 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, and 90 parts by mass, and may be within a range between any two of the 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-, or -NR 2 - or -COO-, and R 2 is -CH3, -C2H5, or -(CH2) a A group represented by -CH(O)CH2 is present, Ar 1 is an unsubstituted phenyl group or a phenyl group substituted with 1 to 4 (e.g., 1, 2, 3, or 4) methyl or ethyl groups, a is an integer between 0 and 5 (e.g., 0, 1, 2, 3, 4, 5), b is an integer between 1 and 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 between 1 and 8 (e.g., 1, 2, 3, 4, 5, 6, 7, 8), and e is an integer between 1 and 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, or 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, compound (B) has two DA reaction adduct moieties, and therefore 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) to a Diels-Alder reaction with a dienophile compound represented by formula (4) or formula (5).

[0023] [ka]

[0024] [ka]

[0025] [ka]

[0026] The dissociation onset temperature of compound (B) is preferably 80 to 190°C. The dissociation onset temperature is the temperature at which dissociation of the DA addition reaction moiety of compound (B) begins, and can be measured by the method described in "3. Evaluation of Epoxy Resin Compositions" below. If the dissociation onset temperature is too low, mechanical properties and thermal properties are likely to deteriorate, while if the dissociation onset temperature is too high, the DA addition reaction moiety of compound (B) is not dissociated during a normal thermal cycle, making it difficult to achieve the stress relaxation effect. Specific examples of the dissociation onset temperature are 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, and 190°C, and may be within a range between any two of the values ​​exemplified here.

[0027] The 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, the compound (B) does not react with the epoxy group of the epoxy resin (A).

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

[0029] The content of curing agent (C) per 100 parts by mass of 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 curing agent (C) is too little or too much, the mechanical properties and thermal properties of the cured epoxy resin product tend to deteriorate. Specific examples of this content are 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, and 90 parts by mass, and may be within a range between any two of the values ​​exemplified here.

[0030] In particular, from the viewpoint of not significantly changing the physical properties of the epoxy resin (A) even when compound (B) is added, it is preferable that the curing agent (C) is contained in the composition so that the total epoxy equivalent of the epoxy resin (A) and compound (B) is close to the functional group equivalent of the curing agent (C). The value of {functional group equivalent of curing agent (C)} / {total epoxy equivalent of the epoxy resin (A) and compound (B)} is, for example, 0.8 to 1.2, specifically, for example, 0.8, 0.9, 1.0, 1.1, or 1.2, and may be within a range between any two of the 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 amine-based curing agents, phenol-based curing agents, acid anhydride-based curing agents, and polycarboxylic acid compounds.

[0033] (amine-based curing agent) Examples of amine-based curing agents 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. Aliphatic polyamines are particularly preferred as amine-based curing agents.

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

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

[0037] Examples of commercially available phenolic curing agents 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 polycarboxylic 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. Specific examples of this content include 0.1, 0.3, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 parts by mass, and may be within a range between any two of the values ​​exemplified here.

[0041] Examples of curing catalysts 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 optionally contain at least one additive selected from the group consisting of 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. The additives may be used singly or in combination of two or more. The content of the additive per 100 parts by mass of the epoxy resin (A) is, for example, 0 to 50 parts by mass, more preferably 0 to 20 parts by mass. Specific examples of the content may include 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, and 50 parts by mass, and may fall within a range between any two of the values ​​exemplified herein.

[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.

[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 a cured epoxy resin product. For example, the epoxy resin composition can be cured by heating or light irradiation.

[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. Specific examples of the curing temperature are 20, 40, 60, 80, 100, 120, 140, 160, 180, 200, 220, 240, 250, 260, 280, and 300°C, and may be within a range between any two of the values ​​exemplified here. Furthermore, the heating time during curing (curing time) is usually 10 to 1,440 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, light such as ultraviolet light, visible light, and infrared light can be used, with ultraviolet light being 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, ultra-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 applying the epoxy resin composition of the present invention onto a substrate or by pouring it into a mold.

[0049] The shape of the cured product of the present invention is not particularly limited, and examples thereof include a plate, sheet, and 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 a one-component type or a two-component type. In the case of a 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, improving storage stability. When in use, the first component and the second component are mixed to allow 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 that is inhibited from cracking and peeling due to thermal stress while suppressing deterioration of the mechanical properties and thermal properties that the epoxy resin originally has.

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

[0053] 1. Preparation of Compound (B) 1-1. Manufacturing Example 1 A reactor equipped with a stirrer, reflux condenser, thermometer, and nitrogen inlet was charged with 66.4 g (0.15 mol) of 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide (BMI-5100: manufactured by Daiwa Chemical Industry Co., Ltd.) and 92.5 g (0.60 mol) of furfuryl glycidyl ether. 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 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 A reactor equipped with a stirrer, reflux condenser, thermometer, and nitrogen inlet was charged with 18.9 g (0.10 mol) of 4-hydroxyphenylmaleimide, 3.22 g (0.01 mol) of tetrabutylammonium bromide, 80 g of 40% by weight aqueous sodium hydroxide solution, and 80 g of toluene. The mixture was heated to 60 °C while introducing nitrogen gas, and 46.3 g (0.50 mol) of epichlorohydrin was added dropwise and 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 over magnesium sulfate, and then concentrated. Next, the concentrated residue and 30.8 g (0.20 mol) of furfuryl glycidyl ether were charged to a reactor equipped with a stirrer, reflux condenser, thermometer, and nitrogen inlet. The mixture was heated to 80 °C while introducing nitrogen gas, and then 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 a 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 A reactor equipped with a stirrer, reflux condenser, thermometer, and nitrogen inlet tube was charged with 50.0 g (0.24 mol) of 9-(hydroxymethyl)anthracene, 7.74 g (0.024 mol) of tetrabutylammonium bromide, 200 g of 40% by mass aqueous sodium hydroxide solution, and 200 g of toluene. The temperature was raised to 60°C while introducing nitrogen gas, and 111.1 g (1.2 mol) of epichlorohydrin was added dropwise, followed by stirring for 2 hours. After completion of the reaction, 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: Daiwa Chemical Industry Co., Ltd.) were charged into a reaction apparatus equipped with a stirrer, reflux condenser, thermometer, and nitrogen inlet tube, and the temperature was raised to 180 ° C while introducing nitrogen gas, followed by stirring 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 to stand in an 80°C environment for 1 hour. Then, jER-828 and compound (B1) were mixed using a glass rod, and the mixture was left to stand 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) using 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 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 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 (PHENOLITE TD-2131); manufactured by DIC PPh3: Triphenylphosphine

[0070] 3. Evaluation of epoxy resin compositions The epoxy resin compositions of the Examples, Comparative Examples, and Reference Examples were subjected to various evaluations. 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, with values ​​close to those of the Reference Examples which did not contain 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 also 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 mechanical and thermal properties inherent to 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 hermetic pan and measured for thermal change using a differential scanning calorimeter (DSC) by heating from 30°C to 200°C at a rate of 10°C / min under a nitrogen stream. A graph of "endothermic heat generation" versus "temperature" was plotted, and the characteristic inflection observed at this time was taken as the glass transition temperature. The glass transition temperature was determined by the midpoint method from the DSC curve. The dissociation onset temperature was determined by the extrapolation onset temperature of the endothermic peak that appeared above the glass transition temperature.

[0074] [Tensile modulus / 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 tensile modulus and maximum tensile stress of the obtained test piece were measured in accordance with JIS-K7161 under the following conditions. Sample size: Dumbbell size 1BA Test speed: 1.0mm / min ·Measurement environment: temperature 25℃ Measurement count: 3 times, calculated from the average value

[0076] [Shear adhesive strength] The epoxy resin composition to be evaluated was applied to a 25 mm wide x 100 mm long x 1.0 mm thick stainless steel plate to obtain a SUS plate coated with a curable composition. Another 25 mm wide x 100 mm long x 1.0 mm thick SUS plate was then attached to the curable composition side of the epoxy resin composition-coated SUS plate, resulting in an adhesive area of ​​25 mm x 12.5 mm and a cured product thickness of 0.20 mm, and secured in place with clips. The plate was then heated at 80°C for 3 hours and then at 120°C for another 3 hours to obtain a test specimen. The shear adhesive strength of the resulting test specimen was measured using a universal tensile tester according to JIS K 6850:1999 (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 a further 3 hours to prepare test specimens measuring 5.0 cm in length, 1.0 cm in width, and 1.0 mm in thickness. The storage modulus of the resulting test specimens was measured under the following conditions using a dynamic viscoelasticity measuring device RSA3 (manufactured by TA Instruments). The storage modulus values ​​listed in the table are those 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 25mm wide x 100mm long x 1.0mm thick stainless steel plate to obtain a curable composition-coated SUS plate. Another 25mm wide x 100mm long x 1.0mm thick SUS plate was then attached to the curable composition-coated side of the epoxy resin composition-coated SUS plate, resulting in an attachment area of ​​25mm x 12.5mm and a cured product thickness of 0.20mm. The SUS plate was then secured in place with clips. The specimen was then heated at 80°C for 3 hours and then at 120°C for 3 hours to obtain a test specimen. The resulting specimen was then left in a 25°C environment for 24 hours. After 150 cycles of -40°C x 30 minutes and 200°C x 30 minutes using a thermal shock tester TSA-71L-A (manufactured by Espec), the specimen was visually inspected for peeling. The test was performed three times for each curable composition, and the values ​​in the table indicate the number of times peeling occurred.

Claims

1. 100 parts by mass of epoxy resin (A), 5 to 90 parts by mass of a compound (B) represented by the following formula (1), 15.0 to 75.0 parts by mass of a curing agent (C); An epoxy resin composition comprising: The epoxy resin composition has a foaming agent content of 0 part by mass relative to 100 parts by mass of the epoxy resin (A). 【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—, or —NR ２ - 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 phenylene group or a phenylene group substituted with 1 to 4 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), and * in formula (2) ３ and * ４ are respectively 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, and e is an integer from 1 to 3; Ar ２ and Ar ３ are respectively an unsubstituted phenylene group, a phenylene group substituted with 1 to 4 methyl groups or ethyl groups, an unsubstituted biphenyldiyl group, or a biphenyldiyl group substituted with 1 to 8 methyl groups 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. 3. The epoxy resin composition according to claim 2, R in the 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. A cured epoxy resin product obtained by curing the epoxy resin composition according to any one of claims 1 to 4.

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