WO2023032971A1 - Epoxy resin composition for compression molding and electronic component device - Google Patents

Abstract

An epoxy resin composition for compression molding which comprises an epoxy resin including a polycyclic structure and/or two or more cyclic structures, a hardener, and an inorganic filler, the content of the inorganic filler being 87.0 mass% or higher with respect to the whole epoxy resin composition for compression molding, the epoxy resin composition having a maximum particle diameter of 2.0 mm or less.

Description

EPOXY RESIN COMPOSITION FOR COMPRESSION MOLDING AND ELECTRONIC PARTS DEVICE

The present disclosure relates to an epoxy resin composition for compression molding and an electronic component device.

Conventionally, epoxy resin compositions have been widely used in the field of encapsulating electronic components such as transistors and ICs (Integrated Circuits). The reason for this is that the epoxy resin has a well-balanced electrical property, moisture resistance, heat resistance, mechanical property, adhesiveness to the insert product, and the like.

Transfer molding is the most common method for sealing electronic components using epoxy resin compositions. On the other hand, in transfer molding, the melted epoxy resin composition is pressurized to flow into the mold, and the flow may cause wire flow. In response to this, techniques for increasing the fluidity of the epoxy resin composition have been investigated, but there is still a problem in suppressing wire flow. Compression molding (compression molding) is known as an alternative molding method to transfer molding. In compression molding, an epoxy resin composition is put into a cavity of a mold and melted, and the mold is closed and pressurized to seal the element. According to compression molding, since the epoxy resin composition hardly flows, the occurrence of wire sweep can be suppressed.

As an epoxy resin composition for encapsulating a semiconductor element by compression molding, for example, Patent Document 1 discloses an epoxy resin, a curing agent, a curing accelerator, an inorganic filler, a fatty acid having a melting point of 70° C. or less, and a boiling point of 200° C. A particulate epoxy resin composition has been proposed which contains a silane coupling agent at a temperature of 100 μm to 3 mm and has a particle size distribution of 85% by mass or more in the range of 100 μm to 3 mm.

JP 2011-153173 A

By the way, when an epoxy resin composition is used as a sealing material for an electronic component device such as a semiconductor package, it is being studied to eliminate members such as heat sinks in order to reduce cost and size. However, if some members such as heat sinks are not used, the electronic component device is likely to warp. Therefore, an epoxy resin composition capable of suppressing warping of electronic component devices is desirable.

For example, by increasing the content of the inorganic filler in the epoxy resin composition, it is possible to suppress warping of the electronic component device. However, when the content of the inorganic filler is increased, wire sweep tends to occur, and it is difficult to simultaneously suppress warpage and wire sweep.

The present disclosure has been made in view of the above, and provides an epoxy resin composition for compression molding capable of suppressing warpage and wire flow in an electronic component device, and an electronic device comprising an element sealed with this composition. The object is to provide a component device.

Specific means for achieving the above object are as follows.
<1> an epoxy resin containing at least one of a polycyclic structure and two or more cyclic structures;
a curing agent;
an inorganic filler;
including
The content of the inorganic filler is 87.0% by mass or more with respect to the total amount of the epoxy resin composition for compression molding,
An epoxy resin composition for compression molding, wherein the maximum particle size of the epoxy resin composition for compression molding is 2.0 mm or less.
<2> The epoxy resin for compression molding according to <1>, wherein the epoxy resin contains at least one epoxy resin selected from the group consisting of naphthalene-type epoxy resins, dicyclopentadiene-type epoxy resins, and biphenylaralkyl-type epoxy resins. Composition.
<3> The epoxy resin composition for compression molding according to <1> or <2>, wherein the epoxy equivalent of the epoxy resin is 200 g/eq to 1000 g/eq.
<4> The epoxy resin composition for compression molding according to any one of <1> to <3>, wherein the inorganic filler contains alumina.
<5> The epoxy resin composition for compression molding according to <4>, wherein the alumina content of the inorganic filler is 40% by mass to 80% by mass.
<6> Any one of <1> to <5>, wherein the content of the epoxy resin containing at least one of the polycyclic structure and two or more ring structures relative to the entire epoxy resin is 5% by mass to 50% by mass 2. The epoxy resin composition for compression molding according to 1.
<7> An electronic component device comprising an element and a cured product of the epoxy resin composition for compression molding according to any one of <1> to <6> for encapsulating the element.

According to the present disclosure, it is possible to provide an epoxy resin composition for compression molding capable of suppressing warpage and wire flow in an electronic component device, and an electronic component device including an element sealed with this composition. .

DETAILED DESCRIPTION OF THE INVENTION Embodiments for carrying out the present invention will be described in detail below. However, the present invention is not limited to the following embodiments. In the following embodiments, the constituent elements (including element steps and the like) are not essential unless otherwise specified. The same applies to numerical values and their ranges, which do not limit the present invention.
In the present disclosure, the term "process" includes a process that is independent of other processes, and even if the purpose of the process is achieved even if it cannot be clearly distinguished from other processes. .
In the present disclosure, the numerical range indicated using "-" includes the numerical values before and after "-" as the minimum and maximum values, respectively.
In the numerical ranges described step by step in the present disclosure, the upper limit or lower limit of one numerical range may be replaced with the upper or lower limit of another numerical range described step by step. . Moreover, in the numerical ranges described in the present disclosure, the upper or lower limits of the numerical ranges may be replaced with the values shown in the examples.
In the present disclosure, each component may contain multiple types of applicable substances. When there are multiple types of substances corresponding to each component in the composition, the content rate or content of each component is the total content rate or content of the multiple types of substances present in the composition unless otherwise specified. means quantity.
A plurality of types of particles corresponding to each component in the present disclosure may be included. When multiple types of particles corresponding to each component are present in the composition, the particle size of each component means a value for a mixture of the multiple types of particles present in the composition, unless otherwise specified.

<Epoxy resin composition for compression molding>
The epoxy resin composition for compression molding of the present disclosure (hereinafter also referred to as "epoxy resin composition").
) contains an epoxy resin containing at least one of a polycyclic structure and two or more cyclic structures (hereinafter also referred to as a “specific epoxy resin”), a curing agent, and an inorganic filler, and an inorganic filler is 87.0% by mass or more based on the total amount of the epoxy resin composition for compression molding, and the maximum particle size of the epoxy resin composition for compression molding is 2.0 mm or less.

By using the epoxy resin composition of the present disclosure for element encapsulation, it is possible to suppress warpage and wire sweep in an electronic component device formed by encapsulating the element. The reason for this is presumed, for example, as follows. The present disclosure is not limited to the following assumptions.

The epoxy resin composition of the present disclosure contains a specific epoxy resin and has an inorganic filler content of 87.0% by mass or more relative to the total amount of the epoxy resin composition for compression molding. A rigid skeleton such as a polycyclic structure and two or more cyclic structures contained in a specific epoxy resin contributes to low thermal expansion and low shrinkage in a cured product when the epoxy resin composition is cured. When the content of the inorganic filler is at least a predetermined amount, it contributes to low thermal expansion and low shrinkage of the cured product. It is presumed that warping in the electronic component device is suitably suppressed by these. On the other hand, when the epoxy resin composition contains a specific epoxy resin and the inorganic filler content is equal to or higher than a predetermined amount, wire sweep is likely to occur.

However, when the maximum particle size of the epoxy resin composition is 2.0 mm or less, the solubility of the epoxy resin composition when heated is improved. It is presumed that this suppresses the occurrence of the aforementioned wire sweep.

As described above, by using the epoxy resin composition of the present disclosure for element encapsulation, it is possible to suppress warpage in an electronic component device formed by encapsulating an element. Even if a member such as a heat sink is eliminated for cost reduction, miniaturization, or the like, warpage of the electronic component device is preferably suppressed.

The maximum particle size of the epoxy resin composition is preferably 1.4 mm or less, more preferably 1.0 mm or less, from the viewpoint of more suitably suppressing the occurrence of wire sweep. Moreover, the maximum particle size of the epoxy resin composition may be 0.5 mm or more.

Components that can be contained in the epoxy resin composition of the present disclosure are described in detail below.

[Specific epoxy resin]
The epoxy resin composition of the present disclosure includes an epoxy resin (specific epoxy resin) containing at least one of a polycyclic structure and two or more types of ring structures. The specific epoxy resin preferably has two or more epoxy groups in one molecule.

In the present disclosure, a polycyclic structure means a ring structure in which at least two ring structures within the polycyclic structure share one or more atoms. For example, the polycyclic structure may be fused rings or bridged fused rings, such as dicyclopentadiene type structures.
In the present disclosure, two or more types of ring structures refer to a single ring (e.g., one aliphatic ring, one aromatic ring, or one heterocyclic ring) and a ring assembly in which two or more rings are bonded with a single bond (e.g., , biphenyl group). Two or more types of ring structures may be two or more types of monocyclic rings, may be two or more types of ring assemblies, and may be a combination of a monocyclic ring such as a benzene ring and a ring assembly such as a biphenyl group. may
In addition, when an epoxy resin contains only one type of ring assembly such as a biphenyl group, it does not correspond to a specific epoxy resin.

The specific epoxy resin is at least one epoxy resin selected from the group consisting of naphthalene-type epoxy resins, dicyclopentadiene-type epoxy resins, and biphenylaralkyl-type epoxy resins, from the viewpoint of more preferably suppressing warping of electronic component devices. preferably included. The specific epoxy resin is more preferably at least one selected from the group consisting of naphthalene-type epoxy resins and dicyclopentadiene-type epoxy resins.

The naphthalene-type epoxy resin is not particularly limited as long as it has an epoxy group and a naphthalene ring structure. For example, it may be an epoxy resin in which two glycidyl ether groups are bonded to one naphthalene ring (e.g., 1,6-bis(glycidyloxy)naphthalene), and a plurality of naphthalene rings may be a connecting group (ether group, methylene group etc.), and at least two naphthalene rings may be epoxy resins in which one glycidyl ether group is bonded to each, and the naphthalene rings and benzene rings are alternately or randomly linked by a linking group (ether group, methylene group, etc.). It may be an epoxy resin in which one or more glycidyl ether groups are bonded to each of at least two naphthalene rings.

Examples of naphthalene-type epoxy resins include epoxy resins represented by the following general formulas (I) to (III).

In general formulas (I) to (III), R ¹ to R ³ each independently represent a substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms. p is an average value, and each p independently represents a number from 1 to 10. Each i independently represents an integer of 0 to 4, j independently represents an integer of 0 to 2, and k independently represents an integer of 0 to 2.
Examples of the substituted or unsubstituted monovalent hydrocarbon group having 1 to 12 carbon atoms for R ¹ to R ³ include an alkyl group and the like.
In general formula (I) or general formula (III), the glycidyloxy groups bonded to the naphthalene ring may be independently bonded to either one of the two benzene rings constituting the naphthalene ring.

The naphthalene type epoxy resin may be a copolymer type epoxy resin obtained by epoxidizing a novolac resin obtained from a naphthol compound, a phenol compound, and an aldehyde compound. For example, a compound having a naphthol skeleton and a compound having a phenol skeleton are used. It may be an epoxy resin obtained by glycidyl-etherifying the novolac-type phenol resin used. Examples of such copolymerized epoxy resins include epoxy resins represented by the following general formula (IV).

In general formula (IV), R ¹⁹ to R ²¹ each independently represent a monovalent organic group having 1 to 18 carbon atoms. i each independently represents an integer of 0 to 3; j independently represents an integer of 0 to 2; k independently represents an integer of 0 to 4; l and m are average values, numbers from 1 to 10, and (l+m) shows numbers from 2 to 20. The terminal of the epoxy resin represented by general formula (IV) is either one of the following formulas (IV-1) or (IV-2). In formulas (IV-1) and (IV-2), the definitions of i, j and k for R ¹⁹ to R ²¹ are the same as the definitions of i, j and k for R ¹⁹ to R ²¹ in formula (IV). is. n is 1 (when linked via a methylene group) or 0 (when not linked via a methylene group).
Among epoxy resins represented by general formula (IV), epoxy resins in which R ²¹ is a methyl group, i is 1, j is 0, and k is 0 are preferable.

Examples of the epoxy resin represented by the general formula (IV) include random copolymers containing l structural units and m structural units at random, alternating copolymers containing alternately, and copolymers containing regularly , a block copolymer containing in a block form, and the like. Any one of these may be used alone, or two or more may be used in combination.

The copolymerized epoxy resin may be a methoxynaphthalene/cresol formaldehyde cocondensed epoxy resin represented by the following general formula (V) containing the following two types of structural units in random, alternating or block order. good. In the following general formula (IV), n and m are each an average value and a number from 1 to 10, (n+m) is a number from 2 to 10, preferably n and m are each an average value, It is a number from 1 to 9, and (n+m) is a number from 2 to 10.

The dicyclopentadiene type epoxy resin is not particularly limited as long as it is an epoxy resin obtained by epoxidizing a compound having a dicyclopentadiene skeleton as a raw material. For example, an epoxy resin represented by the following general formula (VI) is preferred.

In general formula (VI), each R ¹⁶ independently represents a monovalent organic group having 1 to 18 carbon atoms. i each independently represents an integer of 0 to 3; n is the average value and represents a number from 0 to 10.

Examples of biphenyl aralkyl-type epoxy resins include epoxy resins made from phenolic compounds such as phenol and cresol, and phenolic resins synthesized from bis(methoxymethyl)biphenyl or derivatives thereof as raw materials. As such an epoxy resin, for example, an epoxy resin represented by general formula (VII) is preferable.

In general formula (VII), each R ³⁸ independently represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms. Each R ³⁷ independently represents a monovalent organic group having 1 to 18 carbon atoms. l each independently represents an integer of 0 to 3; n is the average value and is a number from 0 to 10.
Among the epoxy resins represented by the general formula (VII) below, epoxy resins in which l is 0 and R ³⁸ is a hydrogen atom are preferred.

The total content of naphthalene-type epoxy resin, dicyclopentadiene-type epoxy resin and biphenylaralkyl-type epoxy resin is preferably 50% by mass to 100% by mass, more preferably 70% by mass to It is more preferably 100% by mass, and even more preferably 90% to 100% by mass.

The epoxy equivalent of the specific epoxy resin is preferably 200 g/eq to 1000 g/eq, more preferably 200 g/eq to 500 g/eq, from the viewpoint of suitably reducing warpage of electronic component devices. The epoxy equivalent of a specific epoxy resin is a value measured by a method according to JIS K 7236:2009.

The epoxy resin composition of the present disclosure may or may not contain epoxy resins other than the specific epoxy resins described above (hereinafter also referred to as "other epoxy resins").

As other epoxy resins, specifically, phenol compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A and bisphenol F and aliphatic aldehyde compounds such as formaldehyde, acetaldehyde and propionaldehyde are mixed under an acidic catalyst. A novolac-type epoxy resin (phenol novolak-type epoxy resin, ortho-cresol novolak-type epoxy resin, etc.) obtained by epoxidizing a novolak resin obtained by condensation or co-condensation with; A triphenylmethane type epoxy resin obtained by epoxidizing a triphenylmethane type phenol resin obtained by condensation or co-condensation with an aromatic aldehyde compound in the presence of an acidic catalyst; diglycidyl ethers such as bisphenol A and bisphenol F; Diphenylmethane-type epoxy resins; biphenyl-type epoxy resins that are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; stilbene-type epoxy resins that are diglycidyl ethers of stilbene-based phenol compounds; sulfur atom-containing diglycidyl ethers such as bisphenol S Epoxy resins; Epoxy resins that are glycidyl ethers of alcohols such as butanediol, polyethylene glycol and polypropylene glycol; Glycidyl ester type epoxy resins that are glycidyl esters of polyvalent carboxylic acid compounds such as phthalic acid, isophthalic acid and tetrahydrophthalic acid; Glycidylamine-type epoxy resins obtained by substituting glycidyl groups for active hydrogens bonded to nitrogen atoms of aniline, diaminodiphenylmethane, isocyanuric acid, etc.; vinylcyclohexene diepoxides obtained by epoxidizing intramolecular olefin bonds; Alicyclic epoxy resins such as 4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate; para-xylylene-modified epoxy resins that are glycidyl ethers of para-xylylene-modified phenol resins; meta-xylylene-modified epoxy resins that are glycidyl ethers of meta-xylylene-modified phenol resins; terpene-modified epoxy resins that are glycidyl ethers of terpene-modified phenol resins; cyclopentadiene-modified epoxy resins that are glycidyl ethers of cyclopentadiene-modified phenol resins; non-type epoxy resins; trimethylolpropane-type epoxy resins; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with a peracid such as peracetic acid; aralkyl-type epoxy resins such as phenol aralkyl resins; Further examples of epoxy resins include epoxidized silicone resins and epoxidized acrylic resins. These other epoxy resins may be used singly or in combination of two or more.

The other epoxy resin may contain at least one of a biphenyl-type epoxy resin and a sulfur atom-containing epoxy resin, or may contain both a biphenyl-type epoxy resin and a sulfur atom-containing epoxy resin.

The epoxy equivalent of other epoxy resins is not particularly limited. From the viewpoint of the balance of various properties such as moldability, reflow resistance and electrical reliability, the functional group equivalent weight of other epoxy resins is preferably 100 g/eq to 1000 g/eq, more preferably 150 g/eq to 500 g/eq. is more preferable. The epoxy equivalent of the epoxy resin is a value measured by a method according to JIS K 7236:2009.

When a specific epoxy resin or other epoxy resin is solid, its softening point or melting point is not particularly limited. From the standpoint of moldability and reflow resistance, the temperature is preferably 40°C to 180°C, and from the standpoint of handleability during preparation of the epoxy resin composition, it is more preferably 50°C to 130°C. The melting points of specific epoxy resins and other epoxy resins are values measured by differential scanning calorimetry (DSC). The softening points of specific epoxy resins and other epoxy resins are values measured by a method (ring and ball method) according to JIS K 7234:1986.

The content of the specific epoxy resin with respect to the total epoxy resin is preferably 5% by mass to 50% by mass, more preferably 10% by mass to 40% by mass, and 15% by mass to 30% by mass. is more preferred.

When the epoxy resin contains other epoxy resins, the content of the other epoxy resins relative to the total epoxy resin may be 50% by mass to 95% by mass, or may be 60% by mass to 90% by mass, It may be 70% by mass to 85% by mass.

When the other epoxy resin contains a biphenyl-type epoxy resin, the content of the biphenyl-type epoxy resin with respect to the total epoxy resin may be 45% by mass to 80% by mass, or 50% by mass to 75% by mass. It may be 55% by mass to 65% by mass.

When the other epoxy resin contains a sulfur atom-containing epoxy resin, the content of the sulfur atom-containing epoxy resin with respect to the entire epoxy resin may be 5% by mass to 30% by mass, or 10% by mass to 25% by mass. may be from 15% by mass to 20% by mass.

The total content of the specific epoxy resin and other epoxy resins in the epoxy resin composition is preferably 0.5% by mass to 50% by mass from the viewpoint of strength, viscosity, heat resistance, moldability, etc. More preferably, it is in the range of 30% by mass to 30% by mass.

[Curing agent]
The epoxy resin composition of the present disclosure contains a curing agent. Examples of curing agents include phenolic curing agents having phenolic hydroxyl groups in the molecule.

Phenol curing agents include, for example, phenolic resins and polyhydric phenol compounds having two or more phenolic hydroxyl groups in one molecule. Specifically, polyhydric phenol compounds such as resorcin, catechol, bisphenol A, bisphenol F, substituted or unsubstituted biphenol; phenol, m-cresol, p-cresol, xylenol, resorcin, catechol, bisphenol A, bisphenol F, At least one phenolic compound selected from the group consisting of phenolic compounds such as phenylphenol and aminophenol, and naphthol compounds such as α-naphthol, β-naphthol and dihydroxynaphthalene, and formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, salicylaldehyde, etc. novolac-type phenolic resin obtained by condensing or co-condensing with an aldehyde compound under an acidic catalyst; aralkyl-type phenolic resin such as; para-xylylene and/or meta-xylylene-modified phenolic resin; melamine-modified phenolic resin; terpene-modified phenolic resin; dicyclopentadiene-type naphthol resin; cyclopentadiene-modified phenolic resin; polycyclic aromatic ring-modified phenolic resin; biphenyl-type phenolic resin; triphenylmethane-type phenolic resins obtained by co-condensation; phenolic resins obtained by copolymerizing two or more of these. These phenol curing agents may be used singly or in combination of two or more.

The functional group equivalent of the curing agent (hydroxyl group equivalent in the case of a curing agent having a phenolic hydroxyl group in its molecule) is not particularly limited. From the viewpoint of the balance of various properties such as moldability, reflow resistance, and electrical reliability, it is preferably 70 g/eq to 1000 g/eq, more preferably 80 g/eq to 500 g/eq.

The functional group equivalent of the curing agent (hydroxyl group equivalent in the case of a curing agent having a phenolic hydroxyl group in its molecule) may be, for example, a value measured by a method according to JIS K 0070:1992.

When the curing agent is solid, its softening point or melting point is not particularly limited. From the viewpoint of moldability and reflow resistance, the temperature is preferably 40° C. to 180° C., and from the viewpoint of handleability during production 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 the value measured in the same manner as the melting point or softening point of the epoxy resin.

The equivalent ratio between the epoxy resin and the curing agent, that is, 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 the curing agent/number of epoxy groups in the epoxy resin) is not particularly limited. From the viewpoint of minimizing each unreacted amount, it is preferably set in the range of 0.5 to 2.0, more preferably in the range of 0.6 to 1.3. From the viewpoint of moldability and reflow resistance, it is more preferable to set the ratio in the range of 0.8 to 1.2.

[Curing accelerator]
The epoxy resin composition may contain a curing accelerator. The type of curing accelerator is not particularly limited, and can be selected according to the type of epoxy resin, desired properties of the epoxy resin composition, and the like.

From the viewpoint of curability and viscosity, the curing accelerator preferably contains a phosphonium compound. Specific examples of phosphonium compounds include triphenylphosphine, diphenyl(p-tolyl)phosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, tris(alkyl/alkoxyphenyl)phosphine, tris(dialkylphenyl)phosphine, tris(trialkylphenyl)phosphine, tris(tetraalkylphenyl)phosphine, tris(dialkoxyphenyl)phosphine, tris(trialkoxyphenyl)phosphine, tris(tetraalkoxyphenyl)phosphine, trialkylphosphine, dialkylarylphosphine, alkyldiaryl Tertiary phosphines such as phosphine, maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy- quinone compounds such as 5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone and phenyl-1,4-benzoquinone, and compounds having a π bond such as diazophenylmethane A compound having intramolecular polarization; the tertiary phosphine or the phosphine compound and 4-bromophenol, 3-bromophenol, 2-bromophenol, 4-chlorophenol, 3-chlorophenol, 2-chlorophenol, 4-iodide Phenol, 3-iodinated phenol, 2-iodinated phenol, 4-bromo-2-methylphenol, 4-bromo-3-methylphenol, 4-bromo-2,6-dimethylphenol, 4-bromo-3,5 -dimethylphenol, 4-bromo-2,6-di-tert-butylphenol, 4-chloro-1-naphthol, 1-bromo-2-naphthol, 6-bromo-2-naphthol, 4-bromo-4'-hydroxy A compound having intramolecular polarization obtained through a step of dehydrohalogenation after reacting a halogenated phenol compound such as biphenyl; Tetra-substituted phosphonium such as tetraphenylphosphonium; Tetra-substituted phosphonium and tetra-substituted borate without a phenyl group bonded to; a salt of a tetra-substituted phosphonium with an anion deprotonated from a phenolic compound, a salt of a tetra-substituted phosphonium with an anion deprotonated from a carboxylic acid compound, etc.

Among the above phosphonium compounds, a compound represented by the following general formula (I-1) (hereinafter also referred to as a specific curing accelerator) is preferable.

In formula (I-1), R ¹ to R ³ are each independently a hydrocarbon group having 1 to 18 carbon atoms, and two or more of R ¹ to R ³ are bonded to each other to form a cyclic structure. R ⁴ to R ⁷ each independently represent a hydrogen atom, a hydroxyl group, or a monovalent organic group having 1 to 18 carbon atoms, and two or more of R ⁴ to R ⁷ are bonded to each other A ring structure may be formed.

The “hydrocarbon group having 1 to 18 carbon atoms” described as R ¹ to R ³ in general formula (I-1) includes an aliphatic hydrocarbon group having 1 to 18 carbon atoms and an aliphatic hydrocarbon group having 6 to 18 carbon atoms. Contains some aromatic hydrocarbon groups.

From the viewpoint of viscosity, the aliphatic hydrocarbon group having 1 to 18 carbon atoms preferably has 1 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 4 to 6 carbon atoms.

The aliphatic hydrocarbon group having 1 to 18 carbon atoms may be a linear or branched aliphatic hydrocarbon group having 1 to 18 carbon atoms, or an alicyclic hydrocarbon group having 3 to 18 carbon atoms. good too. From the viewpoint of ease of production, it is preferably a straight-chain or branched aliphatic hydrocarbon group.

Specific examples of linear or branched aliphatic hydrocarbon groups having 1 to 18 carbon atoms include methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, t-butyl group, Alkyl groups such as pentyl group, hexyl group, octyl group, decyl group and dodecyl group, allyl group, vinyl group and the like are included. A linear or branched aliphatic hydrocarbon group may or may not have a substituent. Examples of substituents include alkoxy groups such as methoxy group, ethoxy group, butoxy group and t-butoxy group, aryl groups such as phenyl group and naphthyl group, hydroxyl group, amino group and halogen atom. A straight-chain or branched aliphatic hydrocarbon group may have two or more substituents, which may be the same or different. When the linear or branched aliphatic hydrocarbon group has a substituent, the total number of carbon atoms contained in the aliphatic hydrocarbon group and the substituent is preferably 1-18. From the viewpoint of curability, unsubstituted alkyl groups are preferred, and unsubstituted alkyl groups having 1 to 8 carbon atoms are more preferred, such as n-butyl, isobutyl, n-pentyl, n-hexyl and n-octyl. groups are more preferred.

Specific examples of alicyclic hydrocarbons having 3 to 18 carbon atoms include cycloalkyl groups such as cyclopentyl group, cyclohexyl group and cycloheptyl group, and cycloalkenyl groups such as cyclopentenyl group and cyclohexenyl group. The alicyclic hydrocarbon group may or may not have a substituent. Substituents include methyl group, ethyl group, butyl group, tert-
Alkyl groups such as butyl, alkoxy groups such as methoxy, ethoxy, butoxy and t-butoxy, aryl groups such as phenyl and naphthyl, hydroxyl, amino and halogen atoms. An alicyclic hydrocarbon group may have two or more substituents, in which case the substituents may be the same or different. When the alicyclic hydrocarbon group has a substituent, the total number of carbon atoms contained in the alicyclic hydrocarbon group and the substituent is preferably 3-18. When the alicyclic hydrocarbon group has a substituent, the position of the substituent is not particularly limited. From the viewpoint of curability, an unsubstituted cycloalkyl group is preferable, an unsubstituted cycloalkyl group having 4 to 10 carbon atoms is more preferable, and a cyclohexyl group, a cyclopentyl group and a cycloheptyl group are more preferable.

The aromatic hydrocarbon group having 6 to 18 carbon atoms preferably has 6 to 14 carbon atoms, more preferably 6 to 10 carbon atoms. The aromatic hydrocarbon group may or may not have a substituent. Examples of substituents include alkyl groups such as methyl group, ethyl group, butyl group and t-butyl group; alkoxy groups such as methoxy group, ethoxy group, butoxy group and t-butoxy group; and aryl groups such as phenyl group and naphthyl group. , a hydroxyl group, an amino group, a halogen atom, and the like. The aromatic hydrocarbon group may have two or more substituents, in which case the substituents may be the same or different. When the aromatic hydrocarbon group has a substituent, the total number of carbon atoms contained in the aromatic hydrocarbon group and the substituent is preferably 6-18. When the aromatic hydrocarbon group has a substituent, the position of the substituent is not particularly limited.

Specific examples of aromatic hydrocarbon groups having 6 to 18 carbon atoms include phenyl, 1-naphthyl, 2-naphthyl, tolyl, dimethylphenyl, ethylphenyl, butylphenyl and t-butyl. A phenyl group, a methoxyphenyl group, an ethoxyphenyl group, a butoxyphenyl group, and a t-butoxyphenyl group can be mentioned. The position of the substituent in these aromatic hydrocarbon groups may be any of the ortho position, meta position and para position. From the viewpoint of viscosity, an unsubstituted aryl group having 6 to 12 carbon atoms or 6 to 12 carbon atoms including substituents is preferable, and an unsubstituted aryl group having 6 to 10 carbon atoms or including substituents is preferred. Aryl groups of 6 to 10 are more preferred, and phenyl, p-tolyl and p-methoxyphenyl groups are even more preferred.

The term “two or more of R ¹ to R ³ may combine with each other to form a cyclic structure” described as R ¹ to R ³ in general formula (I-1) means that R ¹ to R ³ It means that two or three of them are combined to form one divalent or trivalent hydrocarbon group as a whole. Examples of R ¹ to R ³ in this case include alkylene groups such as ethylene, propylene, butylene, pentylene and hexylene which can form a cyclic structure by bonding with a phosphorus atom; alkenylene groups such as ethylene, propylene and butylenylene groups; Examples thereof include substituents capable of forming a ring structure by bonding with a phosphorus atom, such as aralkylene groups such as methylenephenylene groups, and arylene groups such as phenylene, naphthylene and anthracenylene groups. These substituents may be further substituted with alkyl groups, alkoxy groups, aryl groups, aryloxy groups, amino groups, hydroxyl groups, halogen atoms and the like.

The “monovalent organic group having 1 to 18 carbon atoms” described as R ⁴ to R ⁷ in general formula (I-1) above has 1 to 18 carbon atoms and is substituted or unsubstituted. It also includes aliphatic hydrocarbon groups, aromatic hydrocarbon groups, aliphatic hydrocarbon oxy groups, aromatic hydrocarbon oxy groups, acyl groups, hydrocarbon oxycarbonyl groups, and acyloxy groups.

Examples of the aliphatic hydrocarbon group and aromatic hydrocarbon group include those mentioned above as examples of the aliphatic hydrocarbon group and aromatic hydrocarbon group represented by R ¹ to R ³ .

Examples of the aliphatic hydrocarbonoxy group include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, an n-butoxy group, a 2-butoxy group, a t-butoxy group, a cyclopropyloxy group, a cyclohexyloxy group, and a cyclopentyloxy group. , an allyloxy group, an oxy group having a structure in which an oxygen atom is bonded to the above-mentioned aliphatic hydrocarbon groups such as a vinyloxy group, and these aliphatic hydrocarbon oxy groups are further alkyl groups, alkoxy groups, aryl groups, aryloxy groups, amino and those substituted with groups, hydroxyl groups, halogen atoms, and the like.

Examples of the aromatic hydrocarbon oxy group include a phenoxy group, a methylphenoxy group, an ethylphenoxy group, a methoxyphenoxy group, a butoxyphenoxy group, a phenoxyphenoxy group having a structure in which an oxygen atom is bonded to the above aromatic hydrocarbon group, such as a phenoxyphenoxy group. groups, and those in which these aromatic hydrocarbon oxy groups are further substituted with alkyl groups, alkoxy groups, aryl groups, aryloxy groups, amino groups, halogen atoms, and the like.

Examples of the acyl group include aliphatic hydrocarbon carbonyl groups such as formyl group, acetyl group, ethylcarbonyl group, butyryl group, cyclohexylcarbonyl group and allylcarbonyl group, and aromatic hydrocarbon carbonyl groups such as phenylcarbonyl group and methylphenylcarbonyl group. and the like, in which these aliphatic hydrocarbon carbonyl groups or aromatic hydrocarbon carbonyl groups are further substituted with an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, a halogen atom, or the like.

Examples of the hydrocarbon oxycarbonyl group include aliphatic hydrocarbon oxycarbonyl groups such as methoxycarbonyl group, ethoxycarbonyl group, butoxycarbonyl group, allyloxycarbonyl group and cyclohexyloxycarbonyl group, phenoxycarbonyl group, methylphenoxycarbonyl group and the like. aromatic hydrocarbon oxycarbonyl groups, these aliphatic hydrocarbon carbonyloxy groups or aromatic hydrocarbon carbonyloxy groups further substituted with alkyl groups, alkoxy groups, aryl groups, aryloxy groups, amino groups, halogen atoms, etc. things, etc.

Examples of the acyloxy group include aliphatic hydrocarbon carbonyloxy groups such as a methylcarbonyloxy group, an ethylcarbonyloxy group, a butylcarbonyloxy group, an allylcarbonyloxy group and a cyclohexylcarbonyloxy group, a phenylcarbonyloxy group and a methylphenylcarbonyloxy group. etc., these aliphatic hydrocarbon carbonyloxy groups or aromatic hydrocarbon carbonyloxy groups are further substituted with alkyl groups, alkoxy groups, aryl groups, aryloxy groups, amino groups, halogen atoms, etc. and the like.

The term “two or more of R ⁴ to R ⁷ may combine with each other to form a cyclic structure” described for R ⁴ to R ⁷ in the general formula (I-1) means that 2 to 4 It means that R ⁴ to R ⁷ may combine to form one divalent to tetravalent organic group as a whole. In this case, R ⁴ to R ⁷ include alkylene groups such as ethylene, propylene, butylene, pentylene and hexylene; alkenylene groups such as ethylene, propylene, butyleneylene; aralkylene groups such as methylenephenylene; and arylene groups such as phenylene, naphthylene and anthracenylene. Substituents capable of forming a cyclic structure such as groups, their oxy groups or dioxy groups are included. These substituents may be further substituted with alkyl groups, alkoxy groups, aryl groups, aryloxy groups, amino groups, hydroxyl groups, halogen atoms and the like.

R ⁴ to R ⁷ in general formula (I-1) are not particularly limited. For example, each independently selected from a hydrogen atom, a hydroxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted aryloxy group. preferable. Among them, from the viewpoint of availability of raw materials, a hydrogen atom, a hydroxyl group, an aryl group substituted with at least one selected from the group consisting of an unsubstituted or alkyl group and an alkoxy group, or a chain or cyclic alkyl group preferable. Aryl groups that are unsubstituted or substituted with at least one selected from the group consisting of an alkyl group and an alkoxy group include a phenyl group, p-tolyl group, m-tolyl group, o-tolyl group, p-methoxyphenyl group, and the like. is mentioned. Chain or cyclic alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, 2-butyl, t-butyl, octyl and cyclohexyl groups. From the viewpoint of curability, it is preferred that all of R ⁴ to R ⁷ are hydrogen atoms, or that at least one of R ⁴ to R ⁷ is a hydroxyl group and the rest are all hydrogen atoms.

More preferably, two or more of R ¹ to R ³ in general formula (I-1) are alkyl groups having 1 to 18 carbon atoms or cycloalkyl groups having 3 to 18 carbon atoms, and R ⁴ to R ⁷ are All are hydrogen atoms, or at least one is a hydroxyl group and the rest are all hydrogen atoms. More preferably, all of R ¹ to R ³ are alkyl groups having 1 to 18 carbon atoms or cycloalkyl groups having 3 to 18 carbon atoms, and all of R ⁴ to R ⁷ are hydrogen atoms, or at least one is a hydroxyl group. and the rest are all hydrogen atoms.

From the viewpoint of rapid curing, the specific curing accelerator is preferably a compound represented by the following general formula (I-2).

In formula (I-2), R ¹ to R ³ are each independently a hydrocarbon group having 1 to 18 carbon atoms, and two or more of R ¹ to R ³ are bonded to each other to form a cyclic structure. R ⁴ to R ⁶ each independently represent a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and two or more of R ⁴ to R ⁶ are bonded together to form a cyclic structure may be formed.

Specific examples of R ¹ to R ⁶ in general formula (I-2) are the same as specific examples of R ¹ to R ⁶ in general formula (I-1), and preferred ranges are also the same.

Specific examples of the specific curing accelerator include an addition reaction product of triphenylphosphine and 1,4-benzoquinone, an addition reaction product of tri-n-butylphosphine and 1,4-benzoquinone, and tricyclohexylphosphine and 1,4-benzoquinone. addition reaction product of dicyclohexylphenylphosphine and 1,4-benzoquinone, addition reaction product of cyclohexyldiphenylphosphine and 1,4-benzoquinone, addition reaction product of triisobutylphosphine and 1,4-benzoquinone, tricyclopentylphosphine and an addition reaction product of 1,4-benzoquinone.

A specific curing accelerator can be obtained, for example, as an adduct of a tertiary phosphine compound and a quinone compound.
Specific examples of the third phosphine compound include triphenylphosphine, tributylphosphine, dibutylphenylphosphine, butyldiphenylphosphine, ethyldiphenylphosphine, tris(4-methylphenyl)phosphine, tris(4-ethylphenyl)phosphine, tris(4 -propylphenyl)phosphine, tris(4-butylphenyl)phosphine, tris(isopropylphenyl)phosphine, tris(t-butylphenyl)phosphine, tris(2,4-dimethylphenyl)phosphine, tris(2,6-dimethylphenyl) ) phosphine, tris(2,4,6-trimethylphenyl)phosphine, tris(2,6-dimethyl-4-ethoxyphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(4-ethoxyphenyl)phosphine, etc. mentioned. From the viewpoint of moldability, triphenylphosphine and tributylphosphine are preferred.

Specific examples of quinone compounds include o-benzoquinone, p-benzoquinone, diphenoquinone, 1,4-naphthoquinone, and anthraquinone. From the viewpoint of moisture resistance and storage stability, p-benzoquinone is preferred.

The epoxy resin composition may contain a curing accelerator other than the phosphonium compound.
Specific examples of curing accelerators other than phosphonium compounds include 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) and 1,8-diazabicyclo[5.4.0]undecene-7 (DBU). Cyclic amidine compounds such as diazabicycloalkenes such as diazabicycloalkene, 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole; derivatives of the cyclic amidine compounds; the cyclic amidine compounds or the Phenol novolak salts of derivatives; These compounds include maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3- quinone compounds such as dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, and phenyl-1,4-benzoquinone; and compounds with π bonds such as diazophenylmethane. Cyclic amidiniums such as tetraphenylborate salt of DBU, tetraphenylborate salt of DBN, tetraphenylborate salt of 2-ethyl-4-methylimidazole, tetraphenylborate salt of N-methylmorpholine, etc. Compounds; tertiary amine compounds such as pyridine, triethylamine, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol; derivatives of the tertiary amine compounds; tetra-n-butylammonium acetate , tetra-n-butylammonium phosphate, tetraethylammonium acetate, tetra-n-hexylammonium benzoate, and ammonium salt compounds such as tetrapropylammonium hydroxide.

When the epoxy resin composition contains a specific curing accelerator as a curing accelerator, the content of the specific curing accelerator is preferably 30% by mass or more, more preferably 50% by mass or more, of the total curing accelerator. It is preferably 70% by mass or more, and more preferably 70% by mass or more. The content of the specific curing accelerator may be 100% by mass or less of the total curing accelerator.

When the epoxy resin composition contains a curing accelerator, the amount thereof is preferably 0.1 to 30 parts by mass, more preferably 1 to 15 parts by mass with respect to 100 parts by mass of the resin component. more preferred. When the amount of the curing accelerator is 0.1 parts by mass or more with respect to 100 parts by mass of the resin component, there is a tendency for satisfactory curing in a short period of time. When the amount of the curing accelerator is 30 parts by mass or less with respect to 100 parts by mass of the resin component, the curing speed is not too fast and a good molded article tends to be obtained.

[Inorganic filler]
The epoxy resin composition contains an inorganic filler.
The type of inorganic filler is not particularly limited. Specifically, fused silica, crystalline silica, glass, alumina, calcium carbonate, zirconium silicate, calcium silicate, silicon nitride, aluminum nitride, boron nitride, beryllia, zirconia, zircon, fosterite, steatite, spinel, mullite , titania, talc, clay, and mica. Inorganic fillers having a flame retardant effect may also be used. Inorganic fillers having a flame retardant effect include aluminum hydroxide, magnesium hydroxide, composite metal hydroxides such as composite hydroxides of magnesium and zinc, and zinc borate. Among them, fused silica is preferable from the viewpoint of reducing the coefficient of linear expansion, and alumina is preferable from the viewpoint of high thermal conductivity. An inorganic filler may be used individually by 1 type, or may be used in combination of 2 or more types. Examples of the state of the inorganic filler include powders, beads obtained by spheroidizing powders, fibers, and the like.

Note that "using a combination of two or more types of inorganic fillers" means, for example, when using two or more types of inorganic fillers having the same component but different average particle sizes, inorganic fillers having the same average particle size but different components are used. Examples include the case of using two or more types and the case of using two or more types of inorganic fillers having different average particle sizes and types.

In addition, the content of the inorganic filler is 87.0% by mass or more with respect to the entire epoxy resin composition, and from the viewpoint of suppressing warpage of the electronic component device and viscosity, it is 88.0% to 95.0% by mass. % by mass, more preferably 89.0% by mass to 94.0% by mass, even more preferably 90.0% by mass to 93.0% by mass, and 91.0% by mass to It may be 93.0% by mass.

When the inorganic filler contains alumina, the content of alumina is preferably 40% to 80% by mass, more preferably 50% to 80% by mass, and 60% by mass of the total inorganic filler. More preferably, it is up to 75% by mass.

The average particle size of the inorganic filler is not particularly limited. For example, the volume average particle size is preferably 0.2 μm to 80 μm, more preferably 0.5 μm to 70 μm. When the volume average particle size is 0.2 μm or more, the increase in viscosity of the epoxy resin composition tends to be more suppressed. When the volume average particle size is 80 μm or less, the filling property into narrow gaps tends to be further improved. The volume-average particle size of the inorganic filler can be measured as the volume-average particle size (D50) with a particle size distribution analyzer using a laser diffraction scattering method.

The volume average particle size of the inorganic filler in the epoxy resin composition or its cured product can be measured by a known method. For example, the inorganic filler is extracted from the epoxy resin composition or cured product using an organic solvent, nitric acid, aqua regia, etc., and sufficiently dispersed using an ultrasonic disperser or the like to prepare a dispersion. Using this dispersion, the volume average particle diameter of the inorganic filler can be measured from the volume-based particle size distribution measured by a laser diffraction scattering particle size distribution analyzer. Alternatively, the volume-average particle size of the inorganic filler can be measured from the volume-based particle size distribution obtained by embedding the cured product in a transparent epoxy resin or the like and polishing the resulting cross section with a scanning electron microscope. can be done. Furthermore, it is also possible to continuously observe a two-dimensional cross section of the cured product using an FIB device (focused ion beam SEM) or the like, and perform measurement by performing three-dimensional structural analysis.

The maximum particle size (also called cut point) of the inorganic filler is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of the inorganic filler is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

From the viewpoint of the kneadability of the epoxy resin composition, the particle shape of the inorganic filler is preferably spherical rather than square, and the particle size distribution of the inorganic filler is preferably distributed over a wide range.

When obtaining a cured product with high thermal conductivity, the inorganic filler preferably contains alumina, and more preferably contains alumina as a main component. The average particle size of alumina when the inorganic filler contains alumina is not particularly limited. For example, the volume average particle size of alumina is preferably 0.2 μm to 80 μm, more preferably 0.5 μm to 70 μm. When the volume average particle size is 0.2 μm or more, the increase in viscosity of the epoxy resin composition tends to be suppressed. When the volume average particle size is 80 µm or less, the filling property into narrow gaps tends to be improved.

The maximum particle size of alumina is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of alumina is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

In a preferred embodiment, alumina having a volume average particle size of 0.1 μm to 2.0 μm, preferably 0.2 μm to 1.5 μm, more preferably 0.3 μm to 1.0 μm, and a volume average particle size of 2.0 μm to 1.0 μm. Alumina of more than 0 μm and 75 μm or less, preferably 5.0 μm to 55 μm, more preferably 8.0 μm to 20 μm may be used together. By using two or more kinds of alumina having different average particle diameters together, there is a tendency that the filling property can be made suitable.

The shape of alumina is not particularly limited. From the viewpoint of the kneadability of the epoxy resin composition, the particle shape of alumina is preferably spherical.

When the inorganic filler contains alumina, the inorganic filler preferably contains silica in addition to alumina. When the inorganic filler contains silica, the viscosity tends to decrease, and the kneadability and fluidity tend to be improved. In particular, the combined use of fine silica suppresses the generation of burrs when the cured product is made. tend to be In particular, the inorganic filler may comprise finely divided silica, for example silica having a volume average particle size of 0.01 μm to 2.0 μm, more preferably 0.1 μm to 1.5 μm, even more preferably 0.2 μm to 1.0 μm. preferable. From the viewpoint of reducing the elastic modulus and linear expansion coefficient, the inorganic filler preferably contains silica having a large particle size.
The large particle size silica includes silica having a volume average particle size of preferably more than 2.0 μm and 75 μm or less, more preferably 5.0 μm to 55 μm, still more preferably 8.0 μm to 20 μm.

From the viewpoint of reflow resistance, suppression of viscosity increase, etc., the inorganic filler preferably contains silica, and may contain silica as a main component. The average particle size of silica when the inorganic filler contains silica is not particularly limited. For example, the volume average particle size of silica is preferably 0.2 μm to 80 μm, more preferably 0.5 μm to 70 μm. When the volume average particle size is 0.2 μm or more, the increase in viscosity of the epoxy resin composition tends to be suppressed. When the volume average particle size is 80 µm or less, the filling property into narrow gaps tends to be improved. In addition, the inorganic filler may contain fine silica particles, for example, silica having a volume average particle size of 0.01 μm to 2.0 μm, more preferably 0.1 μm to 1.5 μm, further preferably 0.2 μm to 1.0 μm. preferable. When the inorganic filler contains fine silica particles, it tends to improve filling properties in narrow spaces and suppress the generation of burrs when a cured product is obtained.

The maximum particle size of silica is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of silica is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

The shape of silica is not particularly limited. From the viewpoint of the kneadability of the epoxy resin composition, the particle shape of silica is preferably spherical.

When the inorganic filler contains silica, the silica content is not particularly limited, and may be 70% by mass to 100% by mass, or 80% by mass to 100% by mass, based on the total inorganic filler. may be from 90% by mass to 100% by mass. In addition, when silica is used in combination with alumina, the content of silica may be 20% by mass to 60% by mass, or may be 20% by mass to 50% by mass, relative to the total inorganic filler. , 25% by mass to 40% by mass.

[Various additives]
In addition to the components described above, the epoxy resin composition may contain various additives such as coupling agents, ion exchangers, mold release agents, flame retardants, colorants, stress relaxation agents, and the like exemplified below. The epoxy resin composition may contain various additives known in the art as necessary, in addition to the additives exemplified below.

(coupling agent)
When the epoxy resin composition contains an inorganic filler, it may contain a coupling agent in order to enhance the adhesion between the resin component and the inorganic filler. Coupling agents include known coupling agents such as silane-based compounds such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, and vinylsilane, titanium-based compounds, aluminum chelate compounds, and aluminum/zirconium-based compounds. .

When the epoxy resin composition contains a coupling agent, the amount of the coupling agent is preferably 0.05 to 5 parts by mass, more preferably 0.1 to 2 parts by mass with respect to 100 parts by mass of the inorganic filler. 0.5 parts by mass is more preferred. When the amount of the coupling agent is 0.05 parts by mass or more with respect to 100 parts by mass of the inorganic filler, the adhesion to the frame tends to be further improved. When the amount of the coupling agent is 5 parts by mass or less with respect to 100 parts by mass of the inorganic filler, the moldability of the package tends to be further improved.

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

Mg _(1-X) Al _X (OH) ₂ (CO ₃ ) _X/2 ·mH ₂ O (A)
(0<X≤0.5, m is a positive number)

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 15 parts by mass, based on 100 parts by mass of the resin component.

(Release agent)
The epoxy resin composition may contain a mold release agent from the viewpoint of obtaining good releasability from the mold during molding. The release agent is not particularly limited, and conventionally known agents can be used. Specific 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.

When the epoxy resin composition contains a release agent, the amount thereof is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, based on 100 parts by mass of the resin component. When the amount of the release agent is 0.01 parts by mass or more with respect to 100 parts by mass of the resin component, there is a tendency that sufficient releasability can be obtained. When the amount is 15 parts by mass or less, better adhesion tends to be obtained.

Among them, the epoxy resin composition contains a release agent, and the content of the release agent is preferably more than 0% by mass and 2.0% by mass or less with respect to the total mass of the epoxy resin composition, and 0% by mass. % and 1.5 mass % or less, and more preferably 0 mass % or less and 1.2 mass % or less. By containing the releasing agent at the above-mentioned content, it tends to be possible to suppress a significant decrease in appearance, adhesive strength, and laser marking properties, compared to the case where the release agent is contained in a larger amount than the above-mentioned content. Further, according to the epoxy resin composition of the present disclosure, even when the release agent content is within the above range, it tends to be possible to maintain good releasability.

(Flame retardants)
The epoxy resin composition may contain a flame retardant. The flame retardant is not particularly limited, and conventionally known ones can be used. Specific examples include organic or inorganic compounds containing halogen atoms, antimony atoms, nitrogen atoms or phosphorus atoms, and metal hydroxides. A flame retardant may be used individually by 1 type, or may be used in combination of 2 or more type.

When the epoxy resin composition contains a flame retardant, its amount is not particularly limited as long as it is sufficient to obtain the desired flame retardant effect. For example, it is preferably 1 part by mass to 300 parts by mass, more preferably 2 parts by mass to 150 parts by mass, based on 100 parts by mass of the resin component.

(coloring agent)
The epoxy resin composition may further contain a colorant. Examples of coloring agents include known coloring agents such as carbon black, organic dyes, organic pigments, titanium oxide, red lead, and red iron oxide. The content of the coloring agent can be appropriately selected according to the purpose and the like. A coloring agent may be used individually by 1 type, or may be used in combination of 2 or more type.

(Stress relaxation agent)
The epoxy resin composition may contain stress relieving agents such as silicone oil and silicone rubber particles. By containing the stress relaxation agent, it is possible to further reduce the warpage deformation of the package and the occurrence of package cracks. Examples of the stress relaxation agent include commonly used known stress relaxation agents (flexible agents). Specifically, silicone-based, styrene-based, olefin-based, urethane-based, polyester-based, polyether-based, polyamide-based, polybutadiene-based thermoplastic elastomers, NR (natural rubber), NBR (acrylonitrile-butadiene rubber), acrylic Rubber particles such as rubber, urethane rubber, and silicone powder, core-shell such as methyl methacrylate-styrene-butadiene copolymer (MBS), methyl methacrylate-silicone copolymer, and methyl methacrylate-butyl acrylate copolymer Structured rubber particles and the like can be mentioned. A stress relaxation agent may be used individually by 1 type, or may be used in combination of 2 or more type. Among them, a silicone-based stress relieving agent is preferable. Examples of silicone-based stress relieving agents include those having epoxy groups, those having amino groups, and those modified with polyethers.

(Method for preparing epoxy resin composition)
The method for preparing the epoxy resin composition is not particularly limited. As a general method, there can be mentioned a method of thoroughly mixing components in predetermined amounts with a mixer or the like, melt-kneading the mixture with a mixing roll, an extruder or the like, cooling, and pulverizing. More specifically, for example, predetermined amounts of the components described above are uniformly stirred and mixed, kneaded with a kneader, roll, extruder, or the like preheated to 70° C. to 140° C., cooled, and pulverized. can be mentioned.
Furthermore, the particulate epoxy resin composition obtained by pulverization is sieved through a sieve with an opening of 2.0 mm, and the pulverized material that has passed through the sieve is collected to obtain an epoxy resin composition having a maximum particle size of 2.0 mm or less. A resin composition can be obtained. The maximum particle size of the epoxy resin composition can be adjusted by changing the mesh size of the sieve used.

<Electronic parts equipment>
An electronic component device that is an embodiment of the present disclosure includes an element and a cured product of the epoxy resin composition described above that seals the element.
As an electronic component device, elements (active elements such as semiconductor chips, transistors, diodes, thyristors, capacitors, resistors, etc.) , passive elements such as coils, etc.) are sealed with an epoxy resin composition.
More specifically, an element is fixed on a lead frame, and the terminal portion of the element such as a bonding pad and the lead portion are connected by wire bonding, bumps, or the like, and then sealed with an epoxy resin composition. 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), TQFP (Thin Quad Flat Package), etc.; TCP (Tape Carrier Package) having a structure in which elements connected by bumps are sealed with an epoxy resin composition; COB (Chip On Board) modules, hybrid ICs, multi-chip modules, etc., having a structure sealed with a composition; elements are mounted on the surface of a support member having terminals for wiring board connection formed on the back surface, and bumps or wire bonding is performed. BGA (Ball Grid Array), CSP (Chip Size Package), MCP (Multi Chip Package), etc., having a structure in which the element is connected to the wiring formed on the support member by means of the method, and then the element is sealed with an epoxy resin composition. are mentioned. Also, the epoxy resin composition can be suitably used in printed wiring boards.

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[Preparation of epoxy resin composition]
Epoxy resin compositions were prepared by mixing the following materials according to the composition shown in Table 1 and kneading the mixture at a kneading temperature of 100° C. using a twin-screw kneader. The particulate epoxy resin composition obtained by pulverizing the above epoxy resin composition is sieved through a sieve with an opening of 1.0 mm, and the pulverized material that has passed through the sieve is collected to obtain a maximum particle size of 1. An epoxy resin composition having a thickness of 0 mm or less was obtained for each of Examples and Comparative Examples.
In addition, "-" in the following table means that the component is not blended.

(Epoxy resin)
Epoxy resin 1: epoxy resin having a biphenyl skeleton (epoxy equivalent: 196 g/eq, equivalent to other epoxy resins)
Epoxy resin 2: an epoxy resin in which a plurality of naphthalene rings are bonded by ether groups, and one glycidyl ether group is bonded to each of two terminal naphthalene rings (epoxy equivalent: 250 g/eq, corresponding to a specific epoxy resin)
Epoxy resin 3: a sulfur atom-containing epoxy resin that is a diglycidyl ether of bisphenol S (epoxy equivalent: 245 g/eq, equivalent to other epoxy resins)

(curing agent)
・Curing agent: Triphenylmethane type phenolic resin (Hydroxyl equivalent 104 g/eq)
(Curing accelerator)
・Curing accelerator: addition reaction product (coupling agent) of triphenylphosphine and 1,4-benzoquinone
・Coupling agent 1: 3-methacryloxypropyltrimethoxysilane ・Coupling agent 2: 3-mercaptopropyltrimethoxysilane (ion trap agent)
・Magnesium, aluminum hydroxide, carbonate, hydrate (additive)
・Releasing agent: Montan acid ester wax ・Coloring agent: Carbon black (stress relaxation agent)
· Stress relaxation agent 1: a silicone-based stress relaxation agent having an epoxy group · Stress relaxation agent 2: a stress relaxation agent (inorganic filler) containing the following structural units
・ Inorganic filler 1: Fine particle silica (average particle size 0.5 μm)
・ Inorganic filler 2: Large particle silica (average particle size 10 μm)
・Inorganic filler 3: Alumina/silica = mixture with a volume ratio of 9/1 (average particle size: 10 μm)

[Evaluation of epoxy resin composition]
The properties of the epoxy resin compositions prepared in Examples and Comparative Examples were evaluated by the following property tests. Table 1 shows the results.

(1) Spiral flow (SF)
Using a spiral flow measurement mold according to EMMI-1-66, the epoxy resin composition was molded under the conditions of a mold temperature of 150 ° C., a molding pressure of 6.9 MPa, and a curing time of 180 seconds, and the flow distance (cm) asked for

(2) Gel time (GT)
The gel time of the epoxy resin composition was measured using a curastometer (JSR Trading Co., Ltd.) with a sample volume of 1.5 ml at 160°C. The gel time (seconds) was defined as the time at which the torque started to rise in the obtained chart.

(3) Glass transition temperature (Tg), CTE1 (α1) and CTE2 (α2)
Using the epoxy resin composition, a molded product of 4 mm×4 mm×20 mm was obtained with a transfer molding machine under conditions of a mold temperature of 175° C., a curing time of 90 seconds, and a molding pressure of 6.9 MPa. The obtained molding was completely cured at 175° C. for 6 hours, and the coefficient of linear expansion (CTE) was measured using a thermomechanical analyzer (TMA4000SE, NETZSCH). The measurement temperature range was 30° C. to 260° C., and the heating rate was 10° C./min.
The average value of CTE in the range of 40°C to 80°C was defined as α1, and the average value of CTE in the range of 230°C to 250°C was defined as α2.
The intersection point of the tangent line to the CTE in the range of 40° C. to 80° C. and the tangent line to the CTE in the range of 230° C. to 250° C. was taken as the glass transition temperature (Tg).

(4) Room temperature elastic modulus and high temperature elastic modulus Using an epoxy resin composition, using a transfer molding machine, mold temperature 175 ° C., curing time 90 seconds, molding pressure 6.9 MPa length 50 mm × width 5 mm × thickness 2 mm. was obtained. The obtained molding was completely cured at 175° C. for 6 hours to obtain a cured product. Then, using a viscoelasticity measuring device RSA-3 (TA Instruments), the elastic modulus was measured in a three-point bending mode at a heating rate of 10° C./min and a frequency of 1 Hz. From the measurement results, the elastic modulus at room temperature (25° C.) (room temperature elastic modulus) and the elastic modulus at 260° C. (high temperature elastic modulus) were obtained.

(5) Hot hardness The epoxy resin composition is molded with a transfer molding machine under the conditions of a mold temperature of 175 ° C., a curing time of 90 seconds, and a molding pressure of 6.9 MPa. , HD-1120 (Type D)) was used to measure the hot hardness at 175°C.

(6) Viscosity at 140°C The epoxy resin composition is heated and melted, and a rheometer AR2000 (manufactured by TA Instruments) is used with a 40 mm parallel plate at a shear rate of 32.5/sec to 140°C. was measured.

(7) Molding Shrinkage Using an epoxy resin composition, a molded product (equivalent to a cured product before post-curing) was molded using a transfer molding machine under the conditions of a mold temperature of 175° C., a curing time of 90 seconds, and a molding pressure of 6.9 MPa. Obtained. The obtained molding was completely cured at 175° C. for 6 hours to obtain a cured product (corresponding to a cured product after post-curing). Mold shrinkage before and after post-curing was obtained based on the following formula.
Mold shrinkage rate (%) = {(length of cured product before post-curing - length of cured product after post-curing) / (length of cured product before post-curing)} x 100
The length of the cured product is the length of any one side of the rectangular cured product.

(8) Thermal conductivity Using a compression molding machine with an epoxy resin composition, a semiconductor element was sealed under the conditions of a mold temperature of 175 ° C. to 180 ° C., a molding pressure of 7 MPa, and a curing time of 150 seconds, and the thermal conductivity was evaluated. A test piece for The thermal conductivity of the specimen was then measured by the Xenon flash (Xe-flash) method.

As shown in Table 1, by using the epoxy resin compositions of Examples 1 to 4, the values of α1 and α2 are smaller than when the epoxy resin compositions of Comparative Examples 1 and 2 are used, and molding is possible. Shrinkage values also tended to be low. Therefore, by manufacturing an electronic component device using the epoxy resin compositions of Examples 1 to 4, it was possible to suppress warpage in the electronic component device.

[Evaluation of solubility]
An epoxy resin composition was prepared with the composition of Example 1 shown in Table 1. A particulate epoxy resin composition obtained by pulverizing the prepared epoxy resin composition was used as an epoxy resin composition of Comparative Example 3. The epoxy resin composition of Comparative Example 3 was not sieved, and the maximum particle size of the composition exceeded 2.0 mm. Using the epoxy resin compositions of Examples 1 to 4 having a maximum particle size of 1.0 mm or less and the epoxy resin composition of Comparative Example 3, the solubility was evaluated as follows.
First, an aluminum cup (Φ5.5 cm) was placed on a hot plate, and then 5 g of each of the epoxy resin compositions of Examples 1 to 4 and Comparative Example 3 was spread horizontally in the cup. After that, the cup covered with the epoxy resin composition was heated at 175° C. for 3 minutes, and the appearance of the epoxy resin composition after heating was confirmed, and the degree of dissolution of the epoxy resin composition was confirmed. In Examples 1 to 4, the uniformity was higher than in Comparative Example 3, and the entirety was dissolved, and almost no undissolved residue was observed. From this, it was presumed that the use of the epoxy resin compositions of Examples 1 to 4 could suppress the wire sweep.

The disclosure of Japanese Patent Application No. 2021-143465 filed on September 2, 2021 is incorporated herein by reference in its entirety.
All publications, patent applications and technical standards mentioned herein are to the same extent as if each individual publication, patent application and technical standard were specifically and individually noted to be incorporated by reference. incorporated herein by reference.

Claims (7)

an epoxy resin containing at least one of a polycyclic structure and two or more cyclic structures;
a curing agent;
an inorganic filler;
including
The content of the inorganic filler is 87.0% by mass or more with respect to the total amount of the epoxy resin composition for compression molding,
An epoxy resin composition for compression molding, wherein the maximum particle size of the epoxy resin composition for compression molding is 2.0 mm or less. The epoxy resin composition for compression molding according to claim 1, wherein the epoxy resin contains at least one epoxy resin selected from the group consisting of naphthalene-type epoxy resins, dicyclopentadiene-type epoxy resins, and biphenylaralkyl-type epoxy resins. The epoxy resin composition for compression molding according to claim 1 or claim 2, wherein the epoxy equivalent of the epoxy resin is 200 g/eq to 1000 g/eq. The epoxy resin composition for compression molding according to any one of claims 1 to 3, wherein the inorganic filler contains alumina. The epoxy resin composition for compression molding according to claim 4, wherein the content of the alumina with respect to the total inorganic filler is 40% by mass to 80% by mass. 6. The content of the epoxy resin containing at least one of the polycyclic structure and two or more ring structures relative to the entire epoxy resin is 5% by mass to 50% by mass. Epoxy resin composition for compression molding. An electronic component device comprising an element and a cured product of the epoxy resin composition for compression molding according to any one of claims 1 to 6, which seals the element.