Epoxy resin composition, cured product, and electronic component device

Abstract

To provide an epoxy resin composition having excellent reflow resistance, a cured product thereof, and an electronic component device including the cured product.SOLUTION: The epoxy resin composition contains: an epoxy resin; a curing agent containing a compound having a constituent unit of formula (B1) and a constituent unit of formula (B2); an inorganic filler; and a silicone compound. In the formula (B1) and the formula (B2), R2-R5 each independently represent a C1-6 monovalent organic group.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This disclosure relates to epoxy resin compositions, cured products, and electronic component devices. [Background technology]

[0002] Epoxy resin compositions have long been widely used in the field of encapsulating electronic components such as transistors and ICs (Integrated Circuits). This is because epoxy resins offer a good balance of electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesion to inserts. Methods for encapsulating electronic components using epoxy resin compositions include transfer molding, injection molding, and compression molding.

[0003] With the recent miniaturization, weight reduction, and performance improvements of electronic devices, mounting density has increased, and electronic components are increasingly adopting surface-mount packages instead of conventional pin-insertion type packages. When mounting semiconductor devices to a circuit board, conventional pin-insertion type packages are soldered from the back of the circuit board after the pins are inserted, so the package is not directly exposed to high temperatures. However, with surface-mount type packages, the entire semiconductor device is processed in a solder bath or reflow machine, so it is directly exposed to soldering temperatures. As a result, if the package has absorbed moisture, the absorbed moisture expands rapidly during soldering, causing delamination of the adhesive interface, package cracks, etc., which reduces the reliability of the package during the mounting process.

[0004] As a countermeasure to the above problem, a method is known in which the content of inorganic filler in the element encapsulation molding material is increased in order to reduce moisture absorption inside the semiconductor device (see, for example, Patent Document 1).

[0005] Furthermore, a method for improving reflow resistance by reducing the elastic modulus of the cured product is known, which involves incorporating a silicone compound into an epoxy resin composition for semiconductor encapsulation (for example, Patent Document 2). [Prior art documents]

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] On the other hand, when the content of the inorganic filler is increased, the fluidity of the epoxy resin composition tends to decrease, which causes problems such as wire flow during semiconductor encapsulation. In addition, since the silicone compound tends to increase the water absorption when the epoxy resin composition is made into a cured product, the effect of improving the reflow resistance is limited.

[0008] In view of such a situation, the present disclosure relates to providing an epoxy resin composition having excellent reflow resistance, a cured product thereof, and an electronic component device including the cured product.

Means for Solving the Problems

[0009] The means for solving the above problems include the following aspects. <1> An epoxy resin composition containing an epoxy resin, a curing agent containing a structural unit of the following formula (B1) and a structural unit of formula (B2), an inorganic filler, and a silicone compound.

[0010]

Chemical Formula

[0011] In formula (B1) and formula (B2), R 2 ~R 5 each independently represents a monovalent organic group having 1 to 6 carbon atoms, X2 and X3 each independently represent an integer of 0 to 4, X4 and X5 each independently represent integers between 0 and 3. n1 represents a number from 1 to 10. n² represents a number between 1 and 10. The constituent units of formula (B2) exist separately from the constituent units of formula (B1). <2> The epoxy resin comprises at least one selected from the group consisting of biphenyl-type epoxy resins; aralkyl-type epoxy resins; and copolymer-type epoxy resins obtained by epoxidizing a novolac resin obtained by co-condensing a phenol compound, a naphthol compound, and an aldehyde compound under an acidic catalyst. <1> The epoxy resin composition described above. <3> The content of the compound having the constituent units of formula (B1) and formula (B2) relative to the total mass of the curing agent is 30% to 100% by mass. <1> or <2> The epoxy resin composition described above. <4> The inorganic filler content is 50% to 95% by volume relative to the total volume of the epoxy resin composition. <1> ~ <3> The epoxy resin composition described in any one of the following items. <5> The silicone compound has at least one group selected from the group consisting of epoxy groups and phenyl groups. <1> ~ <4> The epoxy resin composition described in any one of the following items. <6> The silicone compound has an epoxy group. <5> The epoxy resin composition described above. <7> The silicone compound has a phenyl group and a methyl group. <5> The epoxy resin composition described above. <8> The content of the silicone compound is 10% to 30% by mass relative to the epoxy resin. <1> ~ <7> The epoxy resin composition described in any one of the following items. <9> <1> ~ <8> A cured product of the epoxy resin composition described in any one of the items. <10> Dynamic viscoelasticity measurements show that the modulus of elasticity at 260°C is 830 MPa or less, under conditions of a heating rate of 10°C / min and a frequency of 1 Hz. <9> The cured product described above. <11> The water absorption rate after 168 hours in an atmosphere of 85°C and 85% relative humidity is 0.20% or less. <9> or <10> The cured product described above. <12> An element and a seal for the element. <9> ~ <11> An electronic component device comprising a cured product as described in any one of the items. [Effects of the Invention]

[0012] This disclosure provides an epoxy resin composition having excellent reflow resistance, a cured product thereof, and an electronic component device containing the cured product. [Modes for carrying out the invention]

[0013] The embodiments for carrying out the embodiments of this disclosure will be described in detail below. However, the embodiments of this disclosure are not limited to the embodiments described below. In the embodiments described below, the components (including elemental steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and do not limit the embodiments of this disclosure.

[0014] In this disclosure, the term "process" includes not only processes that are independent of other processes, but also processes that cannot be clearly distinguished from other processes, provided that the purpose of such process is achieved. In this disclosure, the numerical range indicated using "~" includes the numbers before and after "~" as the minimum and maximum values, respectively. In numerical ranges described in stages within this disclosure, the upper or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described in stages. Furthermore, in numerical ranges described within this disclosure, the upper or lower limit of that range may be replaced with the values ​​shown in the examples. In this disclosure, each component may contain multiple types of the corresponding substance. If multiple types of the substance corresponding to each component are present in the composition, the content or amount of each component means the total content or amount of the multiple types of substances present in the composition, unless otherwise specified. In this disclosure, each component may contain multiple types of particles. If multiple types of particles corresponding to each component are present in the composition, the particle size of each component refers to the value for a mixture of such multiple types of particles present in the composition, unless otherwise specified.

[0015] In this disclosure, if a silicone compound has an epoxy group, the silicone compound having an epoxy group shall not be included in the epoxy resin. In this disclosure, "resin component" in the epoxy resin composition means the component of the epoxy resin composition excluding the inorganic filler. In this disclosure, the content or percentage of each component in the epoxy resin composition means the content or percentage based on the amount excluding volatile components such as solvents, if such volatile components are present in the epoxy resin composition. "Volatile components" means components that volatilize when heated at 150°C for 1 hour.

[0016] Epoxy resin compositions The epoxy resin composition contains an epoxy resin, a curing agent containing a compound having the constituent units of (B1) and (B2) below (hereinafter also referred to as the "specific curing agent"), an inorganic filler, and a silicone compound.

[0017] [ka]

[0018] In equations (B1) and (B2), R 2 ~R 5 Each of these independently represents a monovalent organic group with 1 to 6 carbon atoms. X2 and X3 each independently represent integers from 0 to 4. X4 and X5 each independently represent integers between 0 and 3. n1 represents a number from 1 to 10. n² represents a number between 1 and 10. The constituent units of formula (B2) exist separately from the constituent units of formula (B1).

[0019] The epoxy resin composition disclosed herein has excellent reflow resistance. The reason for this is not entirely clear, but it is thought that the combination of a specific curing agent and a silicone compound allows for a good reduction in elastic modulus while suppressing an increase in water absorption. The following details each component of the epoxy resin composition.

[0020] <Epoxy resin> The epoxy resin composition contains an epoxy resin. The type of epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule. The epoxy resin may be solid or liquid at 25°C and atmospheric pressure, but it is preferably solid. Specifically, novolac-type epoxy resins (phenol novolac-type epoxy resins, orthocresol novolac-type epoxy resins, etc.) are obtained by condensing or co-condensing a novolac resin obtained by condensing or co-condensing a novolac resin obtained by phenol compounds selected from the group consisting of phenol compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene, with an aliphatic aldehyde compound such as formaldehyde, acetaldehyde, or propionaldehyde, under an acidic catalyst; triphenylmethane-type epoxy resins are obtained by condensing or co-condensing a triphenylmethane-type phenol resin obtained by condensing or co-condensing the above phenol compound with an aromatic aldehyde compound such as benzaldehyde or salicylaldehyde, under an acidic catalyst; and novolac resins obtained by co-condensing a novolac resin obtained by co-condensing the above phenol compound and naphthol compound with an aldehyde compound under an acidic catalyst. Copolymer epoxy resins; diphenylmethane-type epoxy resins, which are diglycidyl ethers of bisphenol A, bisphenol F, etc.; biphenyl-type epoxy resins, which are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; stilbene-type epoxy resins, which are diglycidyl ethers of stilbene-based phenol compounds; sulfur atom-containing epoxy resins, which are diglycidyl ethers of bisphenol S, etc.; glycidyl ether-type epoxy resins, which are glycidyl ethers of alcohols such as butanediol, polyethylene glycol, and polypropylene glycol; glycidyl ester-type epoxy resins, which are glycidyl esters of polycarboxylic acid compounds such as phthalic acid, isophthalic acid, and tetrahydrophthalic acid; glycidylamine-type epoxy resins, in which the active hydrogen bonded to the nitrogen atom of aniline, diaminodiphenylmethane, isocyanuric acid, etc., is substituted with a glycidyl group; dicyclopentadiene-type epoxy resins, which are epoxidized from a co-condensation resin of dicyclopentadiene and a phenol compound.Alicyclic epoxy resins such as vinylcyclohexene diepoxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and 2-(3,4-epoxy)cyclohexyl-5,5-spiro(3,4-epoxy)cyclohexane-m-dioxane, which have epoxidized olefin bonds within the molecule; paraxylylene-modified epoxy resins, which are glycidyl ethers of paraxylylene-modified phenol resins; metaxylylene-modified epoxy resins, which are glycidyl ethers of metaxylylene-modified phenol resins; terpene-modified epoxy resins, which are glycidyl ethers of terpene-modified phenol resins; and dicyclopentadiene-modified phenol resins, which are glycidyl ethers of dicyclo Examples include pentadiene-modified epoxy resins; cyclopentadiene-modified epoxy resins, which are glycidyl ethers of cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified epoxy resins, which are glycidyl ethers of polycyclic aromatic ring-modified phenolic resins; naphthalene-type epoxy resins, which are glycidyl ethers of naphthalene ring-containing phenolic resins; halogenated phenol novolac-type epoxy resins; hydroquinone-type epoxy resins; trimethylolpropane-type epoxy resins; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; and aralkyl-type epoxy resins, which are epoxidized aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins. Furthermore, epoxidized acrylic resins can also be cited as epoxy resins. Epoxy resins may be used individually or in combination of two or more types.

[0021] Among the epoxy resins mentioned above, epoxy resins selected from the group consisting of biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, sulfur atom-containing epoxy resins, novolac-type epoxy resins, dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, copolymer-type epoxy resins, and aralkyl-type epoxy resins (these are referred to as "specific epoxy resins") from the viewpoint of balancing reflow resistance and fluidity. Specific epoxy resins may be used individually or in combination of two or more types.

[0022] When the epoxy resin contains a specific epoxy resin, from the viewpoint of exhibiting the performance of the specific epoxy resin, it is preferable that its total content be 30% by mass or more of the total epoxy resin, and more preferably 50% by mass or more.

[0023] Among specific epoxy resins, biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, and sulfur atom-containing epoxy resins are more preferred from the viewpoint of fluidity, and dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, and aralkyl-type epoxy resins are preferred from the viewpoint of heat resistance.

[0024] In one embodiment, the epoxy resin may include at least one selected from the group consisting of biphenyl-type epoxy resins; aralkyl-type epoxy resins; and copolymer-type epoxy resins obtained by epoxidizing a novolac resin obtained by co-condensing a phenol compound and a naphthol compound with an aldehyde compound under an acidic catalyst.

[0025] If the epoxy resin contains a biphenyl-type epoxy resin, the content of the biphenyl-type epoxy resin may be 20% to 100% by mass or 30% to 100% by mass relative to the total mass of the epoxy resin.

[0026] If the epoxy resin contains an aralkyl epoxy resin, the content of the aralkyl epoxy resin may be 50% to 100% by mass, 70% to 100% by mass, or 90% to 100% by mass, relative to the total mass of the epoxy resin.

[0027] When a copolymer epoxy resin obtained by epoxidizing a novolak resin obtained by co-condensing an epoxy resin with a phenolic compound and a naphthol compound and an aldehyde compound under an acidic catalyst is included, the content of the copolymer epoxy resin may be 50% to 100% by mass, 70% to 100% by mass, or 90% to 100% by mass based on the total mass of the epoxy resin.

[0028] Hereinafter, specific examples of preferable epoxy resins will be shown.

[0029] The biphenyl type epoxy resin is not particularly limited as long as it is an epoxy resin having a biphenyl skeleton. For example, an epoxy resin represented by the following general formula (II) is preferable. Among the epoxy resins represented by the following general formula (II), when the positions where oxygen atoms are substituted are the 4- and 4'-positions, the 3,3',5,5'-positions are methyl groups, and the other R 8 is a hydrogen atom, YX-4000 and YX-4000H (trade names of Mitsubishi Chemical Corporation), where all R 8 is a hydrogen atom, 4,4'-bis(2,3-epoxypropoxy)biphenyl where all R 8 is a hydrogen atom, and when all R 8 is a hydrogen atom and R 8 is a mixed product where the 3,3',5,5'-positions are methyl groups when the positions where oxygen atoms are substituted are the 4- and 4'-positions and the other R 8 is a hydrogen atom, such as YL-6121H (trade name of Mitsubishi Chemical Corporation), are commercially available.

[0030]

Chemical formula

[0031] In formula (II), R 8 represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an aromatic group having 4 to 18 carbon atoms, and they may all be the same or different from each other. n is an average value and represents a number from 0 to 10.

[0032] The copolymerized epoxy resin obtained by epoxidizing a novolac resin, which is obtained by co-condensing a naphthol compound and a phenol compound with an aldehyde compound under an acidic catalyst, is not particularly limited as long as it is an epoxy resin that uses compounds having a naphthol skeleton and compounds having a phenol skeleton as raw materials. For example, an epoxy resin obtained by glycidyl etherification of a novolac-type phenol resin using compounds having a naphthol skeleton and compounds having a phenol skeleton is preferred, and an epoxy resin represented by the following general formula (IX) is more preferred. Among the epoxy resins represented by the following general formula (IX), R 21 Products such as NC-7300 (Nippon Kayaku Co., Ltd., trade name), in which the group is a methyl group with i = 1, j = 0, and k = 0, are commercially available.

[0033] [ka]

[0034] In formula (IX), R 19 ~R 21 represents a monovalent organic group having 1 to 18 carbon atoms (preferably an alkyl group or aryl group), and each may be the same or different. i is an integer from 0 to 3, j is an integer from 0 to 2, and k is an integer from 0 to 4. l and m are average values, greater than 0 and less than or equal to 10, and (l+m) is a number greater than 0 and less than or equal to 10. The end of the epoxy resin represented by formula (IX) is the following formula (IX-1) or (IX-2). In formulas (IX-1) and (IX-2), R 19 ~R 21 The definitions of i, j and k are given by R in equation (IX). 19 ~R 21 The definitions of i, j, and k are the same. n is either 1 (when bonded via a methylene group) or 0 (when not bonded via a methylene group).

[0035] [ka]

[0036] Examples of epoxy resins represented by the above general formula (IX) include random copolymers containing l constituent units and m constituent units randomly, alternating copolymers containing units alternately, copolymers containing units regularly, and block copolymers containing units in a block-like manner. Any one of these may be used alone, or two or more may be used in combination.

[0037] As a copolymer epoxy resin, Epiclon HP-5000 (DIC Corporation, trade name), represented by the following general formula, is also preferred, as it is a methoxynaphthalene-cresol-formaldehyde cocondensation epoxy resin containing the following two structural units in a random, alternating, or block order. In the following general formula, n and m are each average values, numbers greater than 0 and less than or equal to 10, and (n+m) represents a number greater than 0 and less than or equal to 10. Preferably, n and m are each average values, numbers from 1 to 9, and (n+m) represents a number from 2 to 10.

[0038] [ka]

[0039] The aralkyl epoxy resin is not particularly limited as long as it is an epoxy resin made from a phenol resin synthesized from at least one compound selected from the group consisting of phenol compounds such as phenol and cresol and naphthol compounds such as naphthol and dimethylnaphthol, and dimethoxyparaxylene, bis(methoxymethyl)biphenyl, or derivatives thereof. For example, an epoxy resin obtained by glycidyl etherification of a phenol resin synthesized from at least one compound selected from the group consisting of phenol compounds such as phenol and cresol and naphthol compounds such as naphthol and dimethylnaphthol, and dimethoxyparaxylene, bis(methoxymethyl)biphenyl, or derivatives thereof is preferred, and epoxy resins represented by the following general formulas (X) and (XI) are more preferred.

[0040] Among the epoxy resins represented by the following general formula (X), i is 0 and R 38NC-3000S (Nippon Kayaku Co., Ltd., product name) has a hydrogen atom, i is 0, and R 38 Epoxy resins in which hydrogen atoms and all R of general formula (II) 8 Efficiency-based epoxy resins, such as CER-3000 (Nippon Kayaku Co., Ltd., trade name), which are mixed with an epoxy resin in which the θ is a hydrogen atom in a mass ratio of 80:20, are commercially available. In addition, among epoxy resins represented by the general formula (XI) below, ESN-175 (Nippon Steel Chemical & Material Co., Ltd., trade name), in which l is 0, j is 0, and k is 0, are commercially available.

[0041] [ka]

[0042] In equations (X) and (XI), R 38 R represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms (preferably an alkyl group or aryl group), and each of these may be the same or different. 37 , R 39 ~R 41 'i' represents a monovalent organic group with 1 to 18 carbon atoms, and each group may be identical or different. 'i' is an independent integer between 0 and 3, 'j' is an independent integer between 0 and 2, 'k' is an independent integer between 0 and 4, and 'l' is an independent integer between 0 and 6. 'n' is the average value, and each number is an independent number between 0 and 10.

[0043] The epoxy equivalent of the epoxy resin is not particularly limited. From the viewpoint of balancing various properties such as moldability, reflow resistance, and electrical reliability, the epoxy equivalent of the epoxy resin is preferably 100 g / eq to 1000 g / eq, more preferably 150 g / eq to 500 g / eq, and even more preferably 160 g / eq to 300 g / eq. The epoxy equivalent of the epoxy resin shall be the value measured by the method in accordance with JIS K 7236:2009.

[0044] When the epoxy resin is solid, its softening point or melting point is not particularly limited. From the viewpoint of moldability and reflow resistance, the softening point or melting point of the epoxy resin is preferably 40°C to 180°C, and from the viewpoint of ease of handling during the preparation of the epoxy resin composition, it is more preferably 50°C to 130°C. The melting point of the epoxy resin shall be the value measured by differential scanning calorimetry (DSC), and the softening point of the epoxy resin shall be the value measured by the method (ring-ball method) in accordance with JIS K 7234:1986.

[0045] The epoxy resin content in the epoxy resin composition is preferably 0.5% to 50% by mass, and more preferably 2% to 30% by mass, from the viewpoint of strength, fluidity, heat resistance, moldability, etc.

[0046] <Hardening agent> The epoxy resin composition contains a curing agent (i.e., a specific curing agent) that includes a compound having the constituent units of formula (B1) and formula (B2) below.

[0047] [ka]

[0048] In equations (B1) and (B2), R 2 ~R 5 Each of these independently represents a monovalent organic group with 1 to 6 carbon atoms. X2 and X3 each independently represent integers from 0 to 4. X4 and X5 each independently represent integers between 0 and 3. n1 represents a number from 1 to 10. n² represents a number between 1 and 10. The constituent units of formula (B2) exist separately from the constituent units of formula (B1).

[0049] Hereinafter, the constituent units of formula (B1) will also be referred to as (B1) units, and the constituent units of formula (B2) will also be referred to as (B2) units. The specific curing agent has n1 (B1) units and n2 (B2) units. The statement "The constituent units of formula (B2) exist separately from the constituent units of formula (B1)" means that the (B2) unit is not a part of the (B1) unit, but rather a constituent unit based on a polymerization component separate from the components that form the (B1) unit. The linking method between the (B1) units and the (B2) units is not particularly limited. If the specific curing agent has multiple (B1) units and multiple (B2) units, the linking method between the (B1) units and the (B2) units may be, for example, block copolymerization or random copolymerization, with block copolymerization being preferred.

[0050] The specific curing agent is preferably a compound represented by the following formula (B).

[0051] [ka]

[0052] In formula (B), R 1 ~R 5 Each of these independently represents a monovalent organic group with 1 to 6 carbon atoms. X1 to X3 each independently represent an integer from 0 to 4. X4 and X5 each independently represent integers between 0 and 3. n1 represents a number from 1 to 10. n2 represents a number between 1 and 10.

[0053] In equations (B1), (B2), and (B), R 1 ~R 5 Each of these is independently a monovalent organic group having 1 to 6 carbon atoms, and preferably a monovalent organic group having 1 to 3 carbon atoms. 1 ~R 5 Examples of monovalent organic groups having 1 to 6 carbon atoms represented by include methyl group, ethyl group, n-propyl group, n-butyl group, pentyl group, hexyl group, isopropyl group, isobutyl group, and t-butyl group.

[0054] In formulas (B1), (B2), and (B), X1 to X3 are each independently preferably 0 to 2, more preferably 0 or 1, and even more preferably 0.

[0055] In formulas (B1), (B2), and (B), X4 and X5 are each independently preferably 0 to 2, more preferably 0 or 1, and even more preferably 0.

[0056] In equations (B1), (B2), and (B), n1 and n2 are the average number of repetitions of the structural units in parentheses, respectively.

[0057] The hydroxyl equivalent of the specific curing agent is preferably 130 g / eq to 200 g / eq, and more preferably 150 g / eq to 180 g / eq. The hydroxyl equivalent of the specific curing agent is measured by the method described below.

[0058] When the specific curing agent is a solid, its softening point or melting point is not particularly limited, but from the viewpoint of moldability and reflow resistance, it is preferably 40°C to 180°C, and from the viewpoint of ease of handling during the manufacture of the epoxy resin composition, it is more preferably 50°C to 130°C. From the viewpoint of improving fluidity and reducing the high-temperature modulus of the cured epoxy resin composition, thereby improving reflow resistance, the softening point or melting point of the specific curing agent is preferably 50°C to 100°C, more preferably 50°C to 75°C, and even more preferably 50°C to 70°C.

[0059] The specific hardening agents may be used individually or in combination of two or more types. In addition to the specified curing agent, other curing agents may be used in combination. The content of the specified curing agent relative to the total mass of the curing agent is preferably 30% to 100% by mass, more preferably 40% to 100% by mass, may be 50% to 100% by mass, or 70% to 100% by mass.

[0060] Other curing agents besides the specified curing agent include phenol curing agents (compounds having a phenolic hydroxyl group in their molecule; excluding the specified curing agent), amine curing agents, acid anhydride curing agents, polymercaptan curing agents, polyaminoamide curing agents, isocyanate curing agents, and blocked isocyanate curing agents. From the viewpoint of improving heat resistance, a phenol curing agent is preferred. The curing agent may be solid or liquid at 25°C and atmospheric pressure, but it is preferably solid.

[0061] Specifically, as phenol curing agents, polyhydric phenol compounds such as resorcinol, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenols; novolac-type phenolic resins obtained by condensing or co-condensing at least one phenolic compound selected from the group consisting of phenol compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, aminophenol, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene, with aldehyde compounds such as formaldehyde, acetaldehyde, and propionaldehyde under an acidic catalyst; and those synthesized from the above phenolic compounds with dimethoxyp-xylene, bis(methoxymethyl)biphenyl, etc. Examples include aralkyl-type phenolic resins (excluding specific curing agents) such as phenol aralkyl resins and naphthol aralkyl resins; paraxylylene and / or metaxylylene-modified phenolic resins; melamine-modified phenolic resins; terpene-modified phenolic resins; dicyclopentadiene-type phenolic resins and dicyclopentadiene-type naphthol resins synthesized by copolymerization of the above phenolic compounds and dicyclopentadiene; cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified phenolic resins; biphenyl-type phenolic resins; triphenylmethane-type phenolic resins obtained by condensation or co-condensation of the above phenolic compounds and aromatic aldehyde compounds such as benzaldehyde and salicylaldehyde under an acidic catalyst; and phenolic resins obtained by copolymerizing two or more of these. The phenolic curing agent may be used alone or in combination of two or more.

[0062] Among phenol curing agents, at least one selected from the group consisting of aralkyl-type phenol resins, dicyclopentadiene-type phenol resins, triphenylmethane-type phenol resins, copolymerized phenol resins of benzaldehyde-type phenol resins and aralkyl-type phenol resins, and novolac-type phenol resins is preferred from the viewpoint of reflow resistance. These phenol curing agents may be used individually or in combination of two or more types.

[0063] In one embodiment, a specific curing agent and an aralkyl-type phenolic resin may be used in combination as the curing agent. The mixing ratio of the two (specific curing agent: aralkyl-type phenolic resin) may be 30:70 to 70:30, or 40:60 to 60:40. In this case, the ratio of the total amount of the specific curing agent and the aralkyl-type phenolic resin to the total amount of curing agent is preferably 60% by mass or more, more preferably 70% by mass or more, and even more preferably 80% by mass or more.

[0064] Examples of aralkyl-type phenolic resins include phenolic aralkyl resins synthesized from phenolic compounds and dimethoxyp-xylene, bis(methoxymethyl)biphenyl, etc., and naphthol aralkyl resins. Aalkyl-type phenolic resins may be further copolymerized with other phenolic resins. Examples of copolymerized aralkyl-type phenolic resins include copolymerized phenolic resins of benzaldehyde-type phenolic resin and aralkyl-type phenolic resin, and copolymerized phenolic resins of salicylaldehyde-type phenolic resin and aralkyl-type phenolic resin.

[0065] The aralkyl-type phenolic resin is not particularly limited as long as it is synthesized from at least one compound selected from the group consisting of phenol compounds and naphthol compounds, and dimethoxyp-xylene, bis(methoxymethyl)biphenyl, or derivatives thereof. For example, phenolic resins represented by the following general formulas (XII) to (XIV) are preferred.

[0066] [ka]

[0067] In equations (XII) to (XIV), R 23 R represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and these may all be the same or different. 22 , R 24 , R 25 and R 28 R represents a monovalent organic group having 1 to 18 carbon atoms, and each of them may be identical or different. 26 and R 27 '' represents a hydroxyl group or a monovalent organic group having 1 to 18 carbon atoms, and each of these may be the same or different. 'i' is an independent integer between 0 and 3, 'j' is an independent integer between 0 and 2, 'k' is an independent integer between 0 and 4, and 'p' is an independent integer between 0 and 4. 'n' is the average value, and each of these is an independent number between 0 and 10.

[0068] Among the phenolic resins represented by the above general formula (XII), i is 0 and R 23 MEH-7851 (Meiwa Chemicals Co., Ltd., product name), which consists entirely of hydrogen atoms, is available commercially.

[0069] Among the phenolic resins represented by the above general formula (XIII), XL-225, XLC (Mitsui Chemicals, Inc., trade name), MEH-7800SS (Meiwa Kasei Co., Ltd., trade name), etc., in which i is 0 and k is 0, are available commercially.

[0070] Among the phenolic resins represented by the above general formula (XIV), SN-170 (Nippon Steel Chemical & Material Co., Ltd., product name) has j = 0, k = 0, and p = 0, while R has j = 0, k = 1. 27 SN-395 (Nippon Steel Chemical & Material Co., Ltd., product name), which has a hydroxyl group and p is 0, is available as a commercially available product.

[0071] The functional group equivalents of curing agents other than the specified curing agent (hydroxyl group equivalents in the case of phenol curing agents, and active hydrogen equivalents in the case of amine curing agents) are not particularly limited. From the viewpoint of balancing various properties such as moldability, reflow resistance, and electrical reliability, the functional group equivalents of curing agents other than the specified curing agent are preferably 70 g / eq to 1000 g / eq, and more preferably 80 g / eq to 500 g / eq.

[0072] In the case of phenolic curing agents, the hydroxyl group equivalent refers to the value calculated based on the hydroxyl value measured in accordance with JIS K0070:1992. In the case of amine-based curing agents, the active hydrogen equivalent refers to the value calculated based on the amine value measured in accordance with JIS K7237:1995.

[0073] If the curing agent is solid, its softening point or melting point is not particularly limited. From the viewpoint of moldability and reflow resistance, the softening point or melting point of the curing agent is preferably 40°C to 180°C, and from the viewpoint of handling during the manufacture of the epoxy resin composition, it is more preferably 50°C to 130°C. The melting point or softening point of the curing agent shall be a value measured in the same manner as the melting point or softening point of the epoxy resin.

[0074] The equivalent ratio of epoxy resin to curing agent, i.e., the ratio of the number of functional groups in the curing agent to the number of epoxy groups in the epoxy resin (number of functional groups in curing agent / number of epoxy groups in epoxy resin), is not particularly limited. In relation to minimizing unreacted components, the equivalent ratio of epoxy resin to curing agent is preferably set in the range of 0.5 to 2.0, and more preferably in the range of 0.6 to 1.3. From the viewpoint of moldability and reflow resistance, it is even more preferable that the equivalent ratio of epoxy resin to curing agent is set in the range of 0.8 to 1.2.

[0075] <Inorganic filler> The epoxy resin composition contains an inorganic filler. The material of the inorganic filler is not particularly limited. Specific examples of inorganic fillers include silica such as fused silica and crystalline silica, glass, alumina, calcium carbonate, zirconium silicate, calcium silicate, silicon nitride, aluminum nitride, boron nitride, magnesium oxide, silicon carbide, beryllia, zirconia, zircon, fossilite, steatite, spinel, mullite, titania, talc, clay, and mica. Inorganic fillers with flame-retardant properties may also be used. Examples of inorganic fillers with flame-retardant properties include aluminum hydroxide, magnesium hydroxide, composite metal hydroxides such as magnesium-zinc composite hydroxides, and zinc borate. Among inorganic fillers, silica such as fused silica is preferred from the viewpoint of reducing the coefficient of thermal expansion, and alumina is preferred from the viewpoint of high thermal conductivity.

[0076] The shape of the inorganic filler is not particularly limited, but a spherical shape is preferred from the viewpoint of filling properties and mold wear resistance.

[0077] Inorganic fillers may be used individually or in combination of two or more types. "Using two or more inorganic fillers in combination" includes, for example, using two or more inorganic fillers with the same components but different average particle sizes, using two or more inorganic fillers with the same average particle size but different components, and using two or more inorganic fillers with different average particle sizes and types.

[0078] When the inorganic filler is particulate, its average particle size is not particularly limited. For example, the overall volume-average particle size of the inorganic filler is preferably 80 μm or less, but may also be 50 μm or less, 40 μm or less, 30 μm or less, or 20 μm or less. Furthermore, the overall volume-average particle size of the inorganic filler is preferably 0.1 μm or more, more preferably 0.2 μm or more, and even more preferably 0.3 μm or more. When the volume-average particle size of the inorganic filler is 0.1 μm or more, the increase in viscosity of the epoxy resin composition tends to be suppressed. When the volume-average particle size of the inorganic filler is 80 μm or less, the ability to fill narrow gaps tends to be further improved. The volume-average particle size of the inorganic filler can be measured as the particle size (D50) when the cumulative amount from the small diameter side reaches 50% in the volume-based particle size distribution measured by a laser diffraction scattering particle size distribution analyzer (e.g., LA920, manufactured by Horiba, Ltd.).

[0079] From the viewpoint of improving the ability to fill narrow gaps, it is preferable that the maximum particle size of the inorganic filler is controlled. The maximum particle size of the inorganic filler may be adjusted as appropriate, and from the viewpoint of filling ability, it is preferably 105 μm or less, more preferably 75 μm or less, and may also be 60 μm or less, or 40 μm or less. The maximum particle size is defined as the particle size (D90) at which the cumulative amount from the smallest diameter side reaches 90% in the volume-based particle size distribution measured by a laser diffraction scattering particle size distribution analyzer (for example, Horiba, Ltd., product name: LA920).

[0080] The content of the inorganic filler is not particularly limited. The inorganic filler content is preferably 50% by volume or more, more preferably 60% by volume or more, even more preferably 70% by volume or more, particularly preferably 75% by volume or more, and most preferably 80% by volume or more, relative to the total volume of the epoxy resin composition. By setting the inorganic filler content to 50% by volume or more of the total epoxy resin composition, it tends to be possible to suitably improve properties such as the coefficient of thermal expansion, thermal conductivity, and elastic modulus of the cured product. Furthermore, the inorganic filler content is preferably 95% by volume or less, more preferably 90% by volume or less, and even more preferably 87% by volume or less, relative to the total volume of the epoxy resin composition. When the inorganic filler content is 95% by volume or less of the total epoxy resin composition, the increase in viscosity of the epoxy resin composition is suppressed, the fluidity is further improved, and the moldability tends to be better. From the above viewpoint, the inorganic filler content is preferably 50% to 95% by volume, more preferably 60% to 95% by volume, even more preferably 70% to 95% by volume, particularly preferably 75% to 90% by volume, and most preferably 80% to 87% by volume, based on the total volume of the epoxy resin composition.

[0081] The inorganic filler content in the cured epoxy resin composition can be measured as follows: First, the total mass of the cured material is measured. The cured material is then fired at 400°C for 2 hours, and then at 700°C for 3 hours to evaporate the resin components, and the mass of the remaining inorganic filler is measured. The volume is calculated from the obtained masses and their respective specific gravities, and the ratio of the volume of inorganic filler to the total volume of the cured material is obtained as the inorganic filler content.

[0082] <Silicone compounds> The epoxy resin composition contains a silicone compound. "Silicone compound" refers to a compound having a main chain formed by siloxane bonds. The silicone compound may be solid or liquid at 25°C. When using an epoxy resin that is solid at 25°C, the silicone compound is preferably solid at 25°C, and more preferably a silicone resin that is solid at 25°C.

[0083] The silicone compound may have groups such as methyl groups, phenyl groups, and epoxy groups from the viewpoint of improving compatibility with resins and reflow resistance. In one embodiment, it is preferable that the silicone compound includes a silicone compound having at least one selected from the group consisting of epoxy groups and phenyl groups.

[0084] In one embodiment, the silicone compound has an epoxy group. When the silicone compound has an epoxy group, it is thought that the silicone compound participates in curing and contributes to curability and a low modulus of elasticity, thus resulting in excellent reflow resistance of the cured product. From the viewpoint of reflow resistance, the epoxy equivalent (molecular weight per epoxy group) of the silicone compound having epoxy groups is preferably 500 g / eq or more, more preferably 800 g / eq or more, and even more preferably 1,000 g / eq or more. From the viewpoint of fluidity, the epoxy equivalent is preferably 100,000 g / eq or less, more preferably 50,000 g / eq or less, and even more preferably 10,000 g / eq or less. From the above viewpoints, the epoxy equivalent is preferably 500 g / eq to 100,000 g / eq, more preferably 800 g / eq to 50,000 g / eq, and even more preferably 1,000 g / eq to 10,000 g / eq.

[0085] The position of the epoxy group in a silicone compound containing an epoxy group is not particularly limited. For example, the epoxy group may be located at the end (one or both ends) of the main chain formed by the siloxane bond, on a side chain, or both. The epoxy group in the silicone compound may be an alicyclic epoxy group.

[0086] In one embodiment, the silicone compound has phenyl and methyl groups. Such a silicone compound has appropriate compatibility with epoxy resins, and tends to have a good balance of stress relaxation, fluidity, and moldability. Furthermore, it is thought that the elastic modulus of the cured product can be suitably suppressed, resulting in suitable reflow resistance.

[0087] From the viewpoint of low elastic modulus of the cured product, the content of the silicone compound is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 15% by mass or more, relative to the total mass of the epoxy resin. From the viewpoint of low water absorption of the cured product, the content of the silicone compound is preferably 35% by mass or less, more preferably 30% by mass or less, and even more preferably 25% by mass or less, relative to the epoxy resin. From the above viewpoints, the content of the silicone compound is preferably 5% to 35% by mass, more preferably 10% to 30% by mass, and even more preferably 15% to 25% by mass, relative to the epoxy resin. It has been found that the epoxy resin composition of this disclosure suppresses the increase in water absorption even when a relatively large amount of silicone compound is blended.

[0088] <Various additives> In addition to the components described above, the epoxy resin composition may contain various additives such as curing accelerators, coupling agents, ion exchangers, mold release agents, flame retardants, colorants, and stress relievers. The epoxy resin composition may also contain, as necessary, various additives commonly used in the art, in addition to the additives exemplified below.

[0089] (Curing accelerator) The epoxy resin composition may contain a curing accelerator. The type of curing accelerator is not particularly limited and may include diazabicycloalkenes such as 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) and 1,8-diazabicyclo[5.4.0]undecene-7 (DBU), cyclic amidine compounds such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, and 2-heptadecylimidazole; derivatives of the cyclic amidine compounds; phenol novolac salts of the cyclic amidine compounds or their derivatives; and quinone compounds such as maleic anhydride, 1,4-benzoquinone, 2,5-tholquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, and phenyl-1,4-benzoquinone. Compounds having intramolecular polarization formed by adding compounds with π bonds, such as diazophenylmethane; cyclic amidinium compounds such as tetraphenylborate salt of DBU, tetraphenylborate salt of DBN, tetraphenylborate salt of 2-ethyl-4-methylimidazole, and tetraphenylborate salt of N-methylmorpholine; tertiary amine compounds such as pyridine, triethylamine, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; derivatives of the above tertiary amine compounds; ammonium salt compounds such as tetra-n-butylammonium acetate, tetra-n-butylammonium phosphate, tetraethylammonium acetate, tetra-n-hexylammonium benzoate, and tetrapropylammonium hydroxide;Organic phosphines such as primary phosphines like ethylphosphine and phenylphosphine, secondary phosphines like dimethylphosphine and diphenylphosphine, triphenylphosphine, diphenyl(p-tolyl)phosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, tris(alkylalkoxyphenyl)phosphine, tris(dialkylphenyl)phosphine, tris(trialkylphenyl)phosphine, tris(tetraalkylphenyl)phosphine, tris(dialkoxyphenyl)phosphine, tris(trialkoxyphenyl)phosphine, tris(tetraalkoxyphenyl)phosphine, trialkylphosphine, dialkylarylphosphine, alkyldiarylphosphine, trinaphthylphosphine, tris(benzyl)phosphine, and other tertiary phosphines; phosphine compounds such as complexes of the above organic phosphines with organoborons; and the above organic phosphines or the above phosphine compounds with maleic anhydride, 1,4-benzoquinone, 2,5-tholquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone Compounds having intramolecular polarization obtained by adding compounds having π bonds, such as quinone compounds like 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, anthraquinone, and diazophenylmethane; and the aforementioned organophosphine or phosphine compound with 4-bromophenol, 3-bromophenol, 2-bromophenol, 4-chlorophenol, 3-chlorophenol, 2-chlorophenol, and 4-iodide pheno Compounds having intramolecular polarization obtained by reacting halogenated phenol compounds such as 3-iodidephenol, 2-iodidephenol, 4-bromo-2-methylphenol, 4-bromo-3-methylphenol, 4-bromo-2,6-dimethylphenol, 4-bromo-3,5-dimethylphenol, 4-bromo-2,6-di-t-butylphenol, 4-chloro-1-naphthol, 1-bromo-2-naphthol, 6-bromo-2-naphthol, and 4-bromo-4'-hydroxybiphenyl, followed by a dehalogenation step;Examples include tetrasubstituted phosphonium compounds such as tetraphenylphosphonium, tetraphenylborate salts of tetrasubstituted phosphoniums such as tetraphenylphosphonium tetra-p-tolylborate, and salts of tetrasubstituted phosphoniums with phenolic compounds; phosphobetaine compounds; and adducts of phosphonium compounds with silane compounds. The curing accelerator may be used alone or in combination of two or more types.

[0090] Particularly suitable curing accelerators include triphenylphosphine, and adducts of triphenylphosphine and quinone compounds.

[0091] The curing accelerator content is preferably 0.1 to 30 parts by mass, and more preferably 1 to 15 parts by mass, per 100 parts by mass of the resin component. When the amount of curing accelerator is 0.1 parts by mass or more per 100 parts by mass of the resin component, curing tends to occur well in a short time. When the amount of curing accelerator is 30 parts by mass or less per 100 parts by mass of the resin component, the curing speed is not too fast, and a good molded product tends to be obtained.

[0092] (Coupling agent) The epoxy resin composition may contain a coupling agent. The type of coupling agent is not particularly limited, and known coupling agents can be used. Examples of coupling agents include silane coupling agents, titanium coupling agents, aluminum chelate compounds, and aluminum / zirconium compounds. One type of coupling agent may be used alone, or two or more types may be used in combination.

[0093] Examples of silane coupling agents include silane compounds such as epoxysilanes, mercaptosilanes, aminosilanes, alkylsilanes, ureidosilanes, and vinylsilanes. Specifically, examples include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, octenyltrimethoxysilane, glycidoxyoctyltrimethoxysilane, and methacryloxyoctyltrimethoxysilane.

[0094] Examples of titanium coupling agents include isopropyl triisostearoyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, isopropyl tri(N-aminoethyl-aminoethyl) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl phosphite) titanate, bis(dioctyl pyrophosphate) oxyacetate titanate, bis(dioctyl pyrophosphate) ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacrylate isostearoyl titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl isostearoyl diacrylic titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, and tetraisopropyl bis(dioctyl phosphite) titanate.

[0095] When the epoxy resin composition contains a coupling agent, the amount of the coupling agent is preferably 0.05 to 20 parts by mass, more preferably 0.1 to 15 parts by mass, per 100 parts by mass of the inorganic filler. When the amount of the coupling agent is 0.05 parts by mass or more per 100 parts by mass of the inorganic filler, the adhesiveness to the metal member tends to improve. When the amount of the coupling agent is 20 parts by mass or less per 100 parts by mass of the inorganic filler, the moldability tends to improve.

[0096] (Ion exchanger) The epoxy resin composition may contain an ion exchanger. In particular, when the epoxy resin composition of the present disclosure is used as a sealing molding material, from the viewpoint of improving the moisture resistance and high-temperature storage characteristics of an electronic component device including the element to be sealed, it is preferable that the epoxy resin composition contains an ion exchanger. The ion exchanger is not particularly limited, and conventionally known ones can be used. Specifically, hydrotalcite compounds, and hydrous oxides of at least one element selected from the group consisting of magnesium, aluminum, titanium, zirconium, and bismuth can be mentioned. The ion exchanger may be used alone or in combination of two or more. Among them, hydrotalcite represented by the following general formula (A) is preferable.

[0097] Mg (1-X) Al X (OH)2(CO3) X / 2 ·mH2O ……(A) (0 < X ≦ 0.5, m is a positive number)

[0098] When the epoxy resin composition contains an ion exchanger, its content is not particularly limited as long as it is sufficient to capture ions such as halogen ions. For example, it is preferably 0.1 to 30 parts by mass, more preferably 1 to 10 parts by mass, per 100 parts by mass of the resin component.

[0099] (Release agent) The epoxy resin composition may contain a release agent to obtain good release properties from the mold during molding. The release agent is not particularly limited, and conventionally known ones can be used. Specifically, examples include carnauba wax, higher fatty acids such as montanic acid and stearic acid, higher fatty acid metal salts, ester waxes such as montanic acid esters, and polyolefin waxes such as oxidized polyethylene and non-oxidized polyethylene. The release agent may be used alone or in combination of two or more types.

[0100] When an epoxy resin composition contains a release agent, the amount is preferably 0.01 to 10 parts by mass, and more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the resin component. When the amount of release agent is 0.01 parts by mass or more per 100 parts by mass of the resin component, sufficient release properties tend to be obtained. When the amount of release agent is 10 parts by mass or less per 100 parts by mass of the resin component, good adhesion and curing properties tend to be obtained.

[0101] (Flame retardant) The epoxy resin composition may contain a flame retardant. The flame retardant is not particularly limited, and conventionally known ones can be used. Specifically, examples include organic or inorganic compounds containing halogen atoms, antimony atoms, nitrogen atoms, or phosphorus atoms, and metal hydroxides. The flame retardant may be used alone or in combination of two or more types.

[0102] If the epoxy resin composition contains a flame retardant, the amount is not particularly limited as long as it is sufficient to obtain the desired flame retardant effect. For example, the amount of flame retardant is preferably 1 to 30 parts by mass, and more preferably 2 to 20 parts by mass, per 100 parts by mass of the resin component.

[0103] (Coloring agent) The epoxy resin composition may further contain a coloring agent. Examples of known coloring agents include carbon black, organic dyes, organic pigments, titanium dioxide, red lead, and red iron oxide. The amount of coloring agent can be appropriately selected depending on the purpose. The coloring agent may be used alone or in combination of two or more types.

[0104] (Stress reliever) The epoxy resin composition may contain stress-relieving agents other than silicone compounds. The inclusion of stress-relieving agents can further reduce package warping and cracking. Examples of commonly used stress-relieving agents (flexible agents) include thermoplastic elastomers such as styrene, olefin, urethane, polyester, polyether, polyamide, and polybutadiene; rubber particles such as NR (natural rubber), NBR (acrylonitrile-butadiene rubber), acrylic rubber, and urethane rubber; and rubber particles having a core-shell structure such as methyl methacrylate-styrene-butadiene copolymer (MBS) and methyl methacrylate-butyl acrylate copolymer. Stress-relieving agents may be used individually or in combination of two or more.

[0105] [Method for preparing epoxy resin compositions] The method for preparing the epoxy resin composition is not particularly limited. A common method involves thoroughly mixing each component using a mixer, then melt-kneading it using a mixing roll, extruder, etc., followed by cooling and pulverization. More specifically, for example, the above-mentioned components are stirred and mixed, then kneaded using a kneader, roll, extruder, etc., which have been preheated to 70°C to 140°C, followed by cooling and pulverization.

[0106] The epoxy resin composition may be solid or liquid at 25°C and atmospheric pressure, but it is preferably solid. The shape of the epoxy resin composition when it is solid is not particularly limited, and examples include powder, granules, and tablets. When the epoxy resin composition is in tablet form, the dimensions and mass should preferably be such that they are suitable for the packaging molding conditions, from the viewpoint of ease of handling.

[0107] Cured epoxy resin composition In one aspect of this disclosure, the cured product is a cured product of the epoxy resin composition described above.

[0108] [Module of elasticity] From the viewpoint of reflow resistance, the elastic modulus of the cured epoxy resin composition at 260°C, as measured by dynamic viscoelasticity measurement, is preferably 830 MPa or less, more preferably 800 MPa or less, even more preferably 750 MPa or less, and particularly preferably 680 MPa or less. Furthermore, from the viewpoint of curability of the molded product, the elastic modulus is preferably 100 MPa or more. From the above viewpoints, the elastic modulus is preferably 100 MPa to 830 MPa, more preferably 100 MPa to 800 MPa, even more preferably 100 MPa to 750 MPa, and particularly preferably 100 MPa to 680 MPa.

[0109] The modulus of elasticity is measured using a viscoelasticity measuring device (e.g., RSA-3, TA Instruments) in three-point bending mode under conditions of a heating rate of 10°C / min and a frequency of 1 Hz. When measuring the elastic modulus of a cured epoxy resin composition before curing, the cured product shall be prepared by molding at 175°C for 90 seconds, followed by post-curing at 175°C for 5 hours, and then measuring the elastic modulus. Specifically, the elastic modulus can be measured by the method described in the examples.

[0110] [Water absorption rate] A lower water absorption rate is preferable for the cured epoxy resin composition. When measured under the following conditions, the water absorption rate of the cured product is preferably 0.20% by mass or less, and more preferably 0.17% by mass or less. The cured material is treated at 85°C and 85% relative humidity for 168 hours, and the water absorption rate is calculated from the increase in mass relative to the mass before water absorption based on the following formula. Water absorption rate (mass %) = {(mass after water absorption - mass before water absorption) / mass before water absorption} × 100 When measuring the water absorption rate of a cured epoxy resin composition before curing, the cured product should be prepared by molding at 175°C for 90 seconds, followed by a 5-hour curing period, and then measuring the water absorption rate. Specifically, the water absorption rate can be measured by the method described in the examples.

[0111] ≪Electronic Components and Equipment≫ An electronic component device according to one aspect of the present disclosure comprises an element and a cured product of the aforementioned epoxy resin composition for sealing the element. Examples of electronic component devices include those in which elements (active elements such as semiconductor chips, transistors, diodes, and thyristors, and passive elements such as capacitors, resistors, and coils) are mounted on support members such as lead frames, pre-wired tape carriers, wiring boards, glass, silicon wafers, and organic substrates, and the resulting element section is sealed with an epoxy resin composition. More specifically, common resin-encapsulated ICs such as DIP (Dual Inline Package), PLCC (Plastic Leaded Chip Carrier), QFP (Quad Flat Package), SOP (Small Outline Package), SOJ (Small Outline J-lead package), TSOP (Thin Small Outline Package), and TQFP (Thin Quad Flat Package) have a structure in which elements are fixed on a lead frame, the terminal parts of the elements such as bonding pads are connected to the lead parts by wire bonding, bumps, etc., and then sealed using an epoxy resin composition by transfer molding, etc.; TCP (Tape Carrier Package) has a structure in which elements connected to a tape carrier by bumps are sealed with an epoxy resin composition; and COB (Chip On) has a structure in which elements connected to wiring formed on a support member by wire bonding, flip-chip bonding, solder, etc., are sealed with an epoxy resin composition. Examples of such modules include boards, hybrid ICs, and multi-chip modules; BGAs (Ball Grid Arrays), CSPs (Chip Size Packages), and MCPs (Multi Chip Packages) which have a structure in which elements are mounted on the surface of a support member having terminals for connecting to a printed circuit board formed on its back surface, the elements are connected to the wiring formed on the support member by bumps or wire bonding, and then the elements are sealed with an epoxy resin composition. Furthermore, epoxy resin compositions can also be suitably used in printed circuit boards.

[0112] Methods for encapsulating electronic components using epoxy resin compositions include low-pressure transfer molding, injection molding, and compression molding. [Examples]

[0113] The embodiments of the present disclosure will now be described in detail with reference to examples, but the embodiments of the present disclosure are not limited to these examples.

[0114] [Preparation of epoxy resin composition] The following ingredients were prepared. • Epoxy resin 1: Methoxynaphthalene-cresolformaldehyde co-condensation epoxy resin (HP-5000 (product name), DIC Corporation, epoxy equivalent 250g / eq, softening point 58℃) • Epoxy resin 2: Biphenyl-type epoxy resin (YX-4000 (product name), Mitsubishi Chemical Corporation, epoxy equivalent 180g / eq~192g / eq, melting point 105℃) • Epoxy resin 3: Aalkyl type epoxy resin (NC-3000 (product name), Nippon Kayaku Co., Ltd., epoxy equivalent 265g / eq~285g / eq, softening point 53℃~63℃) • Hardening agent 1: A compound in formula (B) where x1 to x5 are all 0, n1 is 1 to 10, and n2 is 1 to 10 (MEHC-7841 (trade name), Meiwa Kasei Co., Ltd., hydroxyl group equivalent 164 g / eq to 168 g / eq, softening point 58°C to 65°C) • Hardener 2: Aralkyl-type phenolic resin (MEH-7800 (product name), Meiwa Kasei Co., Ltd., hydroxyl group equivalent 167g / eq~180g / eq, softening point 61℃~90℃) • Hardener 3: Phenol novolac type phenolic resin (H-4 (product name), Meiwa Kasei Co., Ltd., hydroxyl group equivalent 103g / eq~107g / eq, softening point 67℃~75℃) • Curing accelerator: Additive of triphenylphosphine and 1,4-benzoquinone • Coupling agent 1: 3-glycidoxypropyltrimethoxysilane • Coupling agent 2: N-phenyl-3-aminopropyltrimethoxysilane • Release agent: Carnauba wax Pigment: Carbon Black • Ion exchanger: Hydrotalcite compound • Silicone compound 1: Epoxy group-containing silicone resin (DOWSIL® AY42-119 (product name), Dow-Toray Industries, Ltd., epoxy equivalent 1150 g / mol ~ 2150 g / mol) • Silicone compound 2: Silicone resin containing methyl and phenyl groups (KR-480 (product name), Shin-Etsu Chemical Co., Ltd.) • Inorganic filler 1: Spherical silica (volume average particle size 19.0 μm) • Inorganic filler 2: Spherical silica (volume average particle size 0.5 μm)

[0115] Each component shown in Table 1 was blended in the amounts shown in the table (units are parts by mass unless otherwise specified), thoroughly mixed in a mixer, and then melt-kneaded using a twin-shaft kneader under conditions where the average temperature of the kneading section was approximately 100°C. Next, after the molten material was cooled, the solidified material was pulverized into a powder to prepare the desired powdered epoxy resin composition. In the table, blank spaces indicate that the component was not included.

[0116] [Measurement of elastic modulus] An epoxy resin composition was molded at 175°C for 90 seconds, followed by post-curing at 175°C for 5 hours to produce a cured material measuring 50 mm in length, 5 mm in width, and 2 mm in thickness. The viscoelasticity was then measured using an RSA-3 viscoelasticity analyzer (TA Instruments) in three-point bending mode at a heating rate of 10°C / min and a frequency of 1 Hz. The modulus of elasticity (MPa) at 260°C was read from the measurement results.

[0117] [Measurement of water absorption rate] An epoxy resin composition was molded at 175°C for 90 seconds, followed by post-curing at 175°C for 5 hours to produce a cured product. A test specimen with a diameter of 50 mm and a thickness of 3 mm was prepared and treated at 85°C and 85% relative humidity for 168 hours. The water absorption rate was calculated from the increase in mass relative to the mass before water absorption based on the following formula. Water absorption rate (mass %) = {(mass after water absorption - mass before water absorption) / mass before water absorption} × 100

[0118] [Evaluation of reflow resistance] An epoxy resin composition was molded at 175°C for 90 seconds, followed by 5 hours of post-curing to produce a cured product. A QFN package of a PPF lead frame (surface roughened type) was molded and reflow-treated under MSL1 conditions (85°C, 85% relative humidity, 168 hours), and the delamination rate (percentage of delamination area) after reflow was calculated. Reflow resistance was evaluated as follows. AA: Peeling rate 0%~10% A: Peeling rate is more than 10% but less than or equal to 20% B: Peeling rate is more than 20% and less than 30% C: Peeling rate is more than 30% but less than 100% D: Peeling rate is 100%

[0119] [Table 1]

[0120] As shown in the table, each embodiment achieved both a low modulus of elasticity and a low absorption rate, and the peeling rate due to reflow treatment was also lower compared to the comparative example.

Claims

1. It contains an epoxy resin, a curing agent containing a compound having the constituent units of formula (B1) and formula (B2) below, an inorganic filler, and a silicone compound that is solid at 25°C. The content of the compound having the constituent units of formula (B1) and formula (B2) relative to the total mass of the curing agent is 50% to 100% by mass. An epoxy resin composition in which the content of the silicone compound in the epoxy resin is 5% by mass to 25% by mass. 【Chemistry 1】 In equations (B1) and (B2), R ２ ~R ５ Each of these independently represents a monovalent organic group with 1 to 6 carbon atoms. X2 and X3 each independently represent integers from 0 to 4. X4 and X5 each independently represent integers from 0 to 3. n1 represents a number between 1 and 10. n² represents a number between 1 and 10. The constituent units of formula (B2) exist separately from the constituent units of formula (B1).

2. The epoxy resin composition according to claim 1, wherein the epoxy resin comprises at least one selected from the group consisting of biphenyl-type epoxy resins; aralkyl-type epoxy resins; and copolymer-type epoxy resins obtained by epoxidizing a novolac resin obtained by co-condensing a phenol compound and a naphthol compound with an aldehyde compound under an acidic catalyst.

3. The epoxy resin composition according to claim 1 or claim 2, wherein the content of the compound having the constituent units of formula (B1) and formula (B2) is 70% to 100% by mass with respect to the total mass of the curing agent.

4. The epoxy resin composition according to any one of claims 1 to 3, wherein the content of the inorganic filler is 50% to 95% by volume relative to the total volume of the epoxy resin composition.

5. The epoxy resin composition according to any one of claims 1 to 4, wherein the content of the inorganic filler is 80% to 95% by volume relative to the total volume of the epoxy resin composition.

6. The epoxy resin composition according to any one of claims 1 to 5, wherein the silicone compound has at least one group selected from the group consisting of epoxy groups and phenyl groups.

7. The epoxy resin composition according to claim 6, wherein the silicone compound has an epoxy group.

8. The epoxy resin composition according to claim 6, wherein the silicone compound has a phenyl group and a methyl group.

9. The epoxy resin composition according to any one of claims 1 to 8, wherein the content of the silicone compound is 10% to 25% by mass relative to the epoxy resin.

10. A cured product of the epoxy resin composition according to any one of claims 1 to 9.

11. The cured product according to claim 10, wherein the modulus of elasticity at 260°C, measured by dynamic viscoelasticity measurement under the conditions of a heating rate of 10°C / min and a frequency of 1 Hz, is 830 MPa or less.

12. The cured product according to claim 10 or claim 11, wherein the water absorption rate after 168 hours in an atmosphere of 85°C and 85% relative humidity is 0.20% or less.

13. An electronic component device comprising an element and a cured material according to any one of claims 10 to 12 for sealing the element.

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