Resin composition and electronic component device

Abstract

This resin composition contains an epoxy resin, an active ester compound that serves as a curing agent, a high dielectric inorganic filler, and a cyclic carbodiimide compound.

Description

Resin composition and electronic component device

[0001] The present disclosure relates to a resin composition and an electronic component device.

[0002] In recent years, with the demand for electronic devices to be more highly functional and lighter, thinner, shorter, and smaller, the integration and even higher density of electronic components have progressed, and the semiconductor packages used in these electronic devices have become smaller than ever before.Furthermore, the radio waves used for communication in electronic devices have become higher in frequency.

[0003] As semiconductor packages (PKGs) become smaller and more functional, development of antenna-in-packages (AiPs), which are PKGs with antenna functionality, is also underway. Examples of materials for encapsulating antennas include resin compositions containing a curable resin, a curing agent, and an inorganic filler. By using a composition that produces a cured product with a high dielectric constant as the resin composition, it is possible to reduce the size of the AiP.

[0004] In order to reduce the size of semiconductor packages and accommodate high frequencies, high-dielectric resin compositions containing high-dielectric inorganic fillers such as barium titanate have been proposed (see, for example, Patent Documents 1 to 3).

[0005] JP 2015-036410 A JP 2017-057268 A JP 2018-141052 A

[0006] Materials with high dielectric constants generally also have high dielectric dissipation factors. When materials with high dielectric dissipation factors are used, transmission signals are converted into heat due to transmission loss, which can lead to reduced communication efficiency. The amount of transmission loss that occurs when radio waves transmitted for communication are converted into heat in a dielectric is expressed as the product of the square root of the frequency, the relative dielectric constant, and the dielectric dissipation factor. In other words, the transmission signal is more likely to be converted into heat in proportion to its frequency. In particular, in AiP, radio waves used for communication are becoming higher in frequency to accommodate the increasing number of channels associated with the diversification of information. Therefore, resin compositions are required to have both a high dielectric constant and a low dielectric dissipation factor in the cured product after molding.

[0007] From the viewpoint of reducing the dielectric loss tangent of the cured product after molding, it has been considered to use an active ester compound as a curing agent. However, it has become clear that the crosslink density of the cured product of an epoxy resin and an active ester compound is low, resulting in a decrease in strength.

[0008] An object of the present disclosure is to provide a resin composition that, when cured, has both a high dielectric constant and a low dielectric loss tangent and is also excellent in strength, and an electronic component device using the same.

[0009] Specific means for solving the above problems include the following aspects. <1> A resin composition containing an epoxy resin, an active ester compound as a curing agent, a high-dielectric inorganic filler, and a cyclic carbodiimide compound. <2> The resin composition according to <1>, wherein the content of the cyclic carbodiimide compound is 1 part by mass or more per 100 parts by mass of the epoxy resin. <3> The resin composition according to <1> or <2>, wherein the content of the cyclic carbodiimide compound is 50 parts by mass or less per 100 parts by mass of the epoxy resin. <4> The resin composition according to any one of <1> to <3>, wherein the ratio of the total number of functional group equivalents of the entire curing agent and the number of imide group equivalents of the cyclic carbodiimide compound to the number of epoxy group equivalents of the epoxy resin [(number of functional group equivalents of the entire curing agent + number of imide group equivalents of the cyclic carbodiimide compound) / number of epoxy group equivalents of the epoxy resin] is 0.51 to 2.20. <5> The resin composition according to any one of <1> to <4>, wherein the high-dielectric inorganic filler includes a titanium-based inorganic filler. <6> The resin composition according to any one of <1> to <5>, further including at least one selected from the group consisting of a curing accelerator, a coupling agent, an ion exchanger, a release agent, a flame retardant, a colorant, and a stress relaxation agent. <7> The resin composition according to any one of <1> to <6>, which is used for a high-frequency device. <8> The resin composition according to any one of <1> to <6>, which is used for an antenna-in-package. <9> An electronic component device comprising: a support member; an electronic component arranged on the support member; and a cured product of the resin composition according to any one of <1> to <9> that encapsulates the electronic component. <10> The electronic component device according to <9>, wherein the electronic component includes an antenna.

[0010] According to the present disclosure, there are provided a resin composition which, when cured, has both a high dielectric constant and a low dielectric loss tangent and excellent strength, and an electronic component device using the same.

[0011] In the present 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 as long as the purpose of the process is achieved. In the present disclosure, numerical ranges indicated using "to" include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In numerical ranges described in stages in the present disclosure, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another staged numerical range. Furthermore, in numerical ranges described in the present disclosure, the upper or lower limit value of that numerical range may be replaced with a value shown in the examples. In the present disclosure, each component may contain multiple corresponding substances. When multiple substances 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 substances present in the composition, unless otherwise specified. In the present disclosure, each component may contain multiple types of particles. When multiple types of particles corresponding to each component are present in the composition, the particle size of each component means the value for a mixture of the multiple types of particles present in the composition, unless otherwise specified.

[0012] Hereinafter, embodiments for carrying out the present disclosure will be described in detail. However, the present disclosure is not limited to the following embodiments. In the following embodiments, components (including element steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and do not limit the present disclosure.

[0013] The resin composition according to an embodiment of the present disclosure contains an epoxy resin, an active ester compound as a curing agent, a highly dielectric inorganic filler, and a cyclic carbodiimide compound. The reason why the cured product has a high dielectric constant, a low dielectric loss tangent, and excellent strength when configured as described above is not clear, but is presumed to be as follows.

[0014] The resin composition of the present disclosure contains a high-dielectric inorganic filler, which increases the dielectric constant of the cured product. However, the use of a high-dielectric inorganic filler tends to increase not only the dielectric constant but also the dielectric dissipation factor. In contrast, the resin composition of the present disclosure uses an active ester compound, which reduces the dielectric dissipation factor of the cured product. However, a cured product of an epoxy resin and an active ester compound exhibits low crosslink density and reduced strength. Therefore, the resin composition of the present disclosure contains a cyclic carbodiimide compound. Because secondary hydroxyl groups are not generated in the curing reaction between an epoxy resin and an active ester compound, it is thought that the cyclic carbodiimide compound does not react and does not contribute to the strength of the cured product. However, in fact, the strength of the cured product is improved. The reason for this is thought to be that not only the curing reaction between the epoxy resin and the active ester compound but also self-polymerization between the epoxy resins proceeds, which generates secondary hydroxyl groups, and the cyclic carbodiimide compound reacts with these secondary hydroxyl groups. In particular, the carbodiimide compound contains a cyclic structure, which increases the strength of the cured product. Furthermore, it has been revealed that the inclusion of a cyclic carbodiimide compound further reduces the dielectric dissipation factor of the cured product. The reason for this is thought to be that secondary hydroxyl groups generated by self-polymerization of the epoxy resin are consumed in the reaction with the cyclic carbodiimide compound, further reducing the hydroxyl groups that contribute to an increase in the dielectric loss tangent.

[0015] (Epoxy Resin) The type of epoxy resin is not particularly limited as long as it has an epoxy group in the molecule. Specific examples of epoxy resins include novolac epoxy resins (phenol novolac epoxy resins, orthocresol novolac epoxy resins, etc.) obtained by epoxidizing novolac resins obtained by condensing or co-condensing, under an acidic catalyst, at least one phenolic compound selected from the group consisting of phenolic compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, etc., and naphthol compounds such as α-naphthol, β-naphthol, dihydroxynaphthalene, etc., with an aliphatic aldehyde compound such as formaldehyde, acetaldehyde, propionaldehyde, etc.; triphenylmethane epoxy resins obtained by epoxidizing triphenylmethane phenolic resins obtained by condensing or co-condensing, under an acidic catalyst, the above-mentioned phenolic compound with an aromatic aldehyde compound such as benzaldehyde, salicylaldehyde, etc.; and copolymers obtained by epoxidizing novolac resins obtained by co-condensing, under an acidic catalyst, the above-mentioned phenolic compound and naphthol compound with an aldehyde compound. biphenyl-type epoxy resins which are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; biphenyl skeleton-type epoxy resins such as biphenylaralkyl-type epoxy resins; stilbene-type epoxy resins which are diglycidyl ethers of stilbene-based phenolic compounds; sulfur-containing epoxy resins which are diglycidyl ethers of bisphenol S; 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 acids such as phthalic acid, isophthalic acid, and tetrahydrophthalic acid; glycidylamine-type epoxy resins in which active hydrogen atoms bonded to nitrogen atoms of aniline, diaminodiphenylmethane, isocyanuric acid, etc. are substituted with glycidyl groups; dicyclopentadiene-type epoxy resins obtained by epoxidizing a co-condensation resin of dicyclopentadiene and a phenolic 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 are obtained by epoxidizing an olefin bond in the molecule; paraxylylene-modified epoxy resins, which are glycidyl ethers of paraxylylene-modified phenolic resins; metaxylylene-modified epoxy resins, which are glycidyl ethers of metaxylylene-modified phenolic resins; terpene-modified epoxy resins, which are glycidyl ethers of terpene-modified phenolic resins; and dicyclopentadiene-modified epoxy resins, which are glycidyl ethers of dicyclopentadiene-modified phenolic resins. Examples of the epoxy resin include 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 obtained by epoxidizing aralkyl-type phenolic resins, such as phenol aralkyl resins and naphthol aralkyl resins. Epoxidized acrylic resins are also included as epoxy resins. These epoxy resins may be used alone or in combination of two or more.

[0016] The epoxy equivalent (molecular weight / number of epoxy groups) of the epoxy resin is not particularly limited. From the viewpoint of a balance of 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, and more preferably 150 g / eq to 500 g / eq. The epoxy equivalent of the epoxy resin is a value measured by a method in accordance with JIS K 7236:2009.

[0017] When the epoxy resin is solid, the softening point or melting point of the epoxy resin is not particularly limited. The softening point or melting point of the epoxy resin is preferably 40°C to 180°C from the viewpoint of moldability and reflow resistance, and more preferably 50°C to 130°C from the viewpoint of handleability during preparation of the resin composition. The melting point or softening point of the epoxy resin is a value measured by differential scanning calorimetry (DSC) or a method in accordance with JIS K 7234:1986 (ring and ball method).

[0018] The mass proportion of the epoxy resin in the total amount of the resin composition is preferably 0.5 mass % to 30 mass %, more preferably 2 mass % to 20 mass %, and even more preferably 3.5 mass % to 13 mass %, from the viewpoints of strength, fluidity, heat resistance, moldability, etc.

[0019] (Curing Agent) The resin composition contains an active ester compound as a curing agent. The active ester compound may be used alone or in combination of two or more. Here, the active ester compound refers to a compound that has one or more ester groups that react with epoxy groups in one molecule and has the ability to cure epoxy resins.

[0020] When an active ester compound is used, the dielectric loss tangent of the cured product can be kept lower than when a phenolic or amine curing agent is used as the curing agent. The reason for this is presumed to be as follows: In the reaction between an epoxy resin and a phenolic or amine curing agent, secondary hydroxyl groups are generated. In contrast, in the reaction between an epoxy resin and an active ester compound, ester groups are generated instead of secondary hydroxyl groups. Since ester groups have lower polarity than secondary hydroxyl groups, a resin composition containing an active ester compound as a curing agent can keep the dielectric loss tangent of the cured product lower than a resin composition containing only a curing agent that generates secondary hydroxyl groups. Furthermore, while polar groups in a cured product increase the water absorption of the cured product, using an active ester compound as a curing agent can reduce the concentration of polar groups in the cured product, thereby suppressing the water absorption of the cured product. Furthermore, suppressing the water absorption of the cured product, in other words, reducing the polar molecule H ２By reducing the O content, the dielectric loss tangent of the cured product can be further reduced.

[0021] The type of active ester compound is not particularly limited as long as it has one or more ester groups in the molecule that react with an epoxy group. Examples of the active ester compound include phenol ester compounds, thiophenol ester compounds, N-hydroxyamine ester compounds, and esterified products of heterocyclic hydroxy compounds.

[0022] Examples of active ester compounds include ester compounds obtained from at least one of an aliphatic carboxylic acid and an aromatic carboxylic acid and at least one of an aliphatic hydroxy compound and an aromatic hydroxy compound. Ester compounds using an aliphatic compound as a polycondensation component tend to have excellent compatibility with epoxy resins due to the presence of an aliphatic chain. Ester compounds using an aromatic compound as a polycondensation component tend to have excellent heat resistance due to the presence of an aromatic ring.

[0023] Specific examples of active ester compounds include aromatic esters obtained by the condensation reaction of an aromatic carboxylic acid with a phenolic hydroxyl group. Among these, aromatic esters obtained by the condensation reaction of an aromatic carboxylic acid with a phenolic hydroxyl group using a mixture of raw materials: an aromatic carboxylic acid component in which 2 to 4 hydrogen atoms on the aromatic ring of benzene, naphthalene, biphenyl, diphenylpropane, diphenylmethane, diphenyl ether, diphenylsulfonic acid, etc. are substituted with carboxy groups; a monohydric phenol in which one hydrogen atom on the aromatic ring is substituted with a hydroxyl group; and a polyhydric phenol in which 2 to 4 hydrogen atoms on the aromatic ring are substituted with hydroxyl groups. That is, aromatic esters having structural units derived from the aromatic carboxylic acid component, structural units derived from the monohydric phenol, and structural units derived from the polyhydric phenol are preferred.

[0024] Specific examples of the active ester compound include an active ester resin having a structure obtained by reacting a phenolic resin having a molecular structure in which phenolic compounds are bonded via alicyclic hydrocarbon groups with an aromatic dicarboxylic acid or a halide thereof, and an aromatic monohydroxy compound, as described in JP 2012-246367 A. As the active ester resin, a compound represented by the following structural formula (1) is preferred.

[0025]

[0026] In structural formula (1), R １ represents an alkyl group having 1 to 4 carbon atoms; X represents an unsubstituted benzene ring, an unsubstituted naphthalene ring, a benzene ring or naphthalene ring substituted with an alkyl group having 1 to 4 carbon atoms, or a biphenyl group; Y represents a benzene ring, a naphthalene ring, or a benzene ring or naphthalene ring substituted with an alkyl group having 1 to 4 carbon atoms; k is 0 or 1; and n represents the average number of repetitions and is 0.25 to 1.5.

[0027] Specific examples of the compound represented by structural formula (1) include the following exemplary compounds (1-1) to (1-10): In the structural formula, t-Bu is a tert-butyl group.

[0028]

[0029]

[0030] Other specific examples of the active ester compound include a compound represented by the following structural formula (2) and a compound represented by the following structural formula (3), which are described in JP 2014-114352 A.

[0031]

[0032] In structural formula (2), R １ and R ２are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms; Z is an ester-forming structural moiety (z1) selected from the group consisting of an unsubstituted benzoyl group, an unsubstituted naphthoyl group, a benzoyl group or naphthoyl group substituted with an alkyl group having 1 to 4 carbon atoms, and an acyl group having 2 to 6 carbon atoms, or a hydrogen atom (z2); and at least one of Z is an ester-forming structural moiety (z1).

[0033] In structural formula (3), R １ and R ２ are each independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms; Z is an ester-forming structural moiety (z1) selected from the group consisting of an unsubstituted benzoyl group, an unsubstituted naphthoyl group, a benzoyl group or naphthoyl group substituted with an alkyl group having 1 to 4 carbon atoms, and an acyl group having 2 to 6 carbon atoms, or a hydrogen atom (z2); and at least one of Z is an ester-forming structural moiety (z1).

[0034] Specific examples of the compound represented by structural formula (2) include the following exemplary compounds (2-1) to (2-6).

[0035]

[0036] Specific examples of the compound represented by structural formula (3) include the following exemplary compounds (3-1) to (3-6).

[0037]

[0038] Commercially available products of the active ester compound may be used. Examples of commercially available active ester compounds include active ester compounds containing a dicyclopentadiene-type diphenol structure such as "EXB9451," "EXB9460," "EXB9460S," and "HPC-8000-65T" (manufactured by DIC Corporation); active ester compounds containing an aromatic structure such as "EXB9416-70BK," "EXB-8," and "EXB-9425" (manufactured by DIC Corporation); active ester compounds containing an acetylated phenol novolac such as "DC808" (manufactured by Mitsubishi Chemical Corporation); and active ester compounds containing a benzoylated phenol novolac such as "YLH1026" (manufactured by Mitsubishi Chemical Corporation).

[0039] The ester equivalent (molecular weight / number of ester groups) of the active ester compound is not particularly limited. From the viewpoint of a balance of various properties such as moldability, reflow resistance, and electrical reliability, it is preferably 150 g / eq to 400 g / eq, more preferably 170 g / eq to 300 g / eq, and even more preferably 200 g / eq to 250 g / eq. The ester equivalent of the active ester compound is a value measured by a method in accordance with JIS K 0070:1992.

[0040] The equivalent ratio (ester group / epoxy group) between the epoxy resin and the active ester compound is preferably 0.9 or more, more preferably 0.95 or more, and even more preferably 0.97 or more, from the viewpoint of keeping the dielectric loss tangent of the cured product low. The equivalent ratio (ester group / epoxy group) between the epoxy resin and the active ester compound is preferably 1.1 or less, more preferably 1.05 or less, and even more preferably 1.03 or less, from the viewpoint of keeping the unreacted active ester compound low.

[0041] The resin composition may contain a curing agent other than the active ester compound. The type of the other curing agent is not particularly limited and can be selected depending on the desired properties of the resin composition. Examples of the other curing agent include a phenol curing agent, an amine curing agent, an acid anhydride curing agent, a polymercaptan curing agent, a polyaminoamide curing agent, an isocyanate curing agent, and a blocked isocyanate curing agent. One type of the other curing agent may be used alone, or two or more types may be used in combination.

[0042] Specific examples of the phenolic curing agent include polyhydric phenolic compounds such as resorcinol, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenols; novolak-type phenolic resins obtained by condensing or co-condensing at least one phenolic compound selected from the group consisting of phenolic compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, and aminophenol, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene, with an aldehyde compound such as formaldehyde, acetaldehyde, and propionaldehyde, under an acidic catalyst; and resins synthesized from the above phenolic compounds and dimethoxyparaxylene, bis(methoxymethyl)biphenyl, or the like. Examples of the phenolic curing agent include aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins; paraxylylene-modified phenolic resins and 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-mentioned phenolic compounds with 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-mentioned phenolic compounds with aromatic aldehyde compounds such as benzaldehyde and salicylaldehyde under an acidic catalyst; and phenolic resins obtained by copolymerization of two or more of these. These phenolic curing agents may be used alone or in combination of two or more.

[0043] The functional group equivalent of the other curing agent (hydroxyl group equivalent in the case of a phenolic curing agent) 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 of the other curing agent is preferably 70 g / eq to 1000 g / eq, and more preferably 80 g / eq to 500 g / eq. The functional group equivalent of the other curing agent (hydroxyl group equivalent in the case of a phenolic curing agent) is a value measured by a method in accordance with JIS K 0070:1992.

[0044] The softening point or melting point of the curing agent 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 handleability during production of the resin composition, it is more preferably 50°C to 130°C. The melting point or softening point of the curing agent is a value measured in the same manner as the melting point or softening point of the epoxy resin.

[0045] The equivalent ratio between the epoxy resin and the curing agent (all curing agents when multiple curing agents are used), i.e., the ratio of the number of functional groups in the curing agent to the number of functional groups in the epoxy resin (number of functional groups in the curing agent / number of functional groups in the epoxy resin), is not particularly limited. From the viewpoint of minimizing unreacted components, 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 even more preferably set in the range of 0.8 to 1.2.

[0046] The mass proportion of the active ester compound in the total amount of the active ester compound and other curing agents is preferably 80 mass % or more, more preferably 85 mass % or more, and even more preferably 90 mass % or more, from the viewpoint of keeping the dielectric loss tangent of the cured product low.

[0047] The total mass proportion of the epoxy resin and the active ester compound in the total amount of the epoxy resin and the curing agent is preferably 80 mass % or more, more preferably 85 mass % or more, and even more preferably 90 mass % or more, from the viewpoint of keeping the dielectric loss tangent of the cured product low.

[0048] (Cyclic Carbodiimide Compound) A cyclic carbodiimide compound is a compound having one or more carbodiimide groups (-N=C=N-) in the molecule, and having a cyclic structure in which two nitrogen atoms constituting the carbodiimide group are linked by a linking group. One type of cyclic carbodiimide compound may be used alone, or two or more types may be used in combination.

[0049] From the viewpoint of improving the strength of the resin composition when it is cured, the cyclic carbodiimide compound preferably contains two or more carbodiimide groups in the molecule.

[0050] The cyclic carbodiimide compound may have one cyclic structure or two or more cyclic structures. When the compound has two or more cyclic structures, the two rings may share two or more atoms, such as a bicyclo structure or a tricyclo structure, or the two rings may share one atom, such as a spiro structure. Furthermore, the atoms constituting the cyclic structure may have a cyclic group as a substituent, thereby resulting in a structure having two or more cyclic structures.

[0051] Examples of the cyclic carbodiimide compound include compounds represented by the following general formula (1).

[0052]

[0053] In general formula (1), X is a divalent or higher linking group. When X is a trivalent or higher linking group, it may be bonded to a polymer or to another cyclic structure. The linking group represented by X contains carbon atoms and hydrogen atoms, and may further contain heteroatoms. Examples of heteroatoms include oxygen atoms, nitrogen atoms, sulfur atoms, and phosphorus atoms.

[0054] The number of atoms (membership) of the cyclic structure comprising the carbodiimide group and X is not particularly limited, and is, for example, preferably 8 to 50, more preferably 10 to 30, and even more preferably 10 to 20. The number of members here does not include the number of atoms of substituents.

[0055] Specific examples of the linking group represented by X include an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, a combination of these, or a combination of these with a hetero atom.

[0056] Examples of the aliphatic hydrocarbon group represented by X include an alkylene group having 1 to 20 carbon atoms, an alkanetriyl group having 1 to 20 carbon atoms, and an alkanetetrayl group having 1 to 20 carbon atoms. The aliphatic hydrocarbon group may have a substituent. Examples of the substituent include an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

[0057] Examples of the alicyclic hydrocarbon group represented by X include a cycloalkylene group having 3 to 20 carbon atoms, a cycloalkanetriyl group having 3 to 20 carbon atoms, and a cycloalkanetetrayl group having 3 to 20 carbon atoms. The alicyclic hydrocarbon group may have a substituent. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

[0058] Examples of the aromatic hydrocarbon group include an arylene group having 5 to 15 carbon atoms, an arenetriyl group having 5 to 15 carbon atoms, and an arenetetrayl group having 5 to 15 carbon atoms. The aromatic hydrocarbon group may have a substituent. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group.

[0059] The molecular weight of the cyclic carbodiimide compound is preferably 100 to 3,000, more preferably 100 to 2,500, and even more preferably 250 to 2,500.

[0060] The imide equivalent of the cyclic carbodiimide compound is preferably 25 to 500, more preferably 25 to 325, and even more preferably 62 to 325.

[0061] The cyclic carbodiimide compound may be solid or liquid at room temperature (25°C). When the cyclic carbodiimide compound is solid, it may be in any shape, and may be particulate. When the cyclic carbodiimide compound is particulate, the average particle size of the particles is preferably 200 μm or less, more preferably 100 μm or less, even more preferably 20 μm or less, particularly preferably 10 μm or less, and extremely preferably 8 μm or less. Furthermore, the average particle size of the cyclic carbodiimide compound is preferably 0.1 μm or more, more preferably 0.5 μm or more, and even more preferably 0.8 μm or more.

[0062] In the present disclosure, the average particle size of a cyclic carbodiimide compound refers to the volume average particle size, specifically the particle size (D50) at which the cumulative total from the smallest particle size side reaches 50% in a volume-based particle size distribution curve obtained by a laser diffraction scattering method.

[0063] When the cyclic carbodiimide compound is in the form of particles, the maximum particle size (Dmax) of the particles is preferably 2 mm or less, more preferably 800 μm or less, even more preferably 100 μm or less, and particularly preferably 50 μm or less. The maximum particle size (Dmax) of the cyclic carbodiimide compound is preferably 1 μm or more, more preferably 3 μm or more, and even more preferably 5 μm or more.

[0064] In the present disclosure, the maximum particle size (Dmax) of the cyclic carbodiimide compound refers to the maximum particle size on a volume-based particle size distribution curve determined by a laser diffraction scattering method.

[0065] When the cyclic carbodiimide compound has a spiro structure, examples of the cyclic carbodiimide compound include compounds represented by the following general formula (2).

[0066]

[0067] In the formula, X is a tetravalent group represented by the following formula (3): １ ~Ar ４are each independently an ortho-phenylene group or a 1,2-naphthalene-diyl group which may have a substituent. Examples of the substituent include an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 15 carbon atoms, a halogen atom, a nitro group, an amide group, a hydroxyl group, an ester group, an ether group, and an aldehyde group. １ ~Ar ４ may contain a heteroatom to form a heterocyclic structure. Examples of the heteroatom include an oxygen atom, a nitrogen atom, a sulfur atom, and a phosphorus atom.

[0068]

[0069] Specific examples of the compound represented by formula (2) include the following compounds.

[0070]

[0071] These cyclic carbodiimide compounds can be produced by well-known methods described in various literatures, patent publications, and the like.

[0072] Commercially available cyclic carbodiimide compounds include TCC-FP10M (Teijin Limited, trade name).

[0073] The content of the cyclic carbodiimide compound in the resin composition is not particularly limited, and is, for example, preferably 0.05% by mass to 20% by mass of the entire resin composition, more preferably 0.1% by mass to 20% by mass, even more preferably 0.2% by mass to 15% by mass, and particularly preferably 0.5% by mass to 10% by mass.

[0074] The content of the cyclic carbodiimide compound per 100 parts by mass of the epoxy resin is not particularly limited, and from the viewpoint of increasing the strength of the cured product, it is preferably 1 part by mass or more, more preferably 3 parts by mass or more, even more preferably 5 parts by mass or more, and particularly preferably 10 parts by mass or more.

[0075] Furthermore, from the viewpoint of suppressing a decrease in hardness immediately after molding, the content of the cyclic carbodiimide compound per 100 parts by mass of the epoxy resin is preferably 50 parts by mass or less, more preferably 45 parts by mass or less, even more preferably 40 parts by mass or less, and particularly preferably 30 parts by mass or less.

[0076] The ratio of the total number of functional group equivalents of the entire curing agent and the number of imide group equivalents of the cyclic carbodiimide compound to the number of epoxy group equivalents of the epoxy resin [(number of functional group equivalents of the entire curing agent + number of imide group equivalents of the cyclic carbodiimide compound) / number of epoxy group equivalents of the epoxy resin] is preferably 0.51 to 2.20, more preferably 0.61 to 1.50, even more preferably 0.81 to 1.40, and particularly preferably 1.01 to 1.20.

[0077] (Inorganic Filler) The resin composition contains a high-dielectric inorganic filler. A high-dielectric inorganic filler refers to an inorganic filler having a relative dielectric constant of 8 or more at 10 GHz. One type of high-dielectric inorganic filler may be used alone, or two or more types may be used in combination. The high-dielectric inorganic filler preferably has a relative dielectric constant of 8 to 100 at 10 GHz.

[0078] In the present disclosure, the relative dielectric constant of the inorganic filler at 10 GHz is a value measured by the following method. A resin composition consisting of 100 parts by mass of an epoxy resin (biphenyl aralkyl epoxy resin, epoxy equivalent 274 g / eq), 74.8 parts by mass of a phenolic curing agent (phenolic aralkyl resin, hydroxyl group equivalent 205 g / eq), and 2 parts by mass of a 1,4-benzoquinone adduct of triphenylphosphine, an inorganic filler, and methyl ethyl ketone (MEK) was mixed, and the resin composition was dissolved in MEK to prepare a varnish (75% by mass of the resin composition and inorganic filler in total). Varnishes with inorganic filler contents of 10%, 20%, and 30% by volume, based on the solid content excluding the solvent, were prepared. The resulting varnish was applied to a substrate, and the substrate was dried at 100°C for 10 minutes, after which the resin film was peeled off from the substrate. The obtained resin film is compression molded under the conditions of a mold temperature of 175 ° C, a molding pressure of 6.9 MPa, and a curing time of 600 seconds to obtain a cured product for measurement. The dielectric constant of each obtained cured product for measurement at 10 GHz is measured, and a graph is created in which the inorganic filler content is plotted on the horizontal axis and the measured dielectric constant is plotted on the vertical axis. From the obtained graph, a linear approximation is performed using the least squares method, and the dielectric constant when the inorganic filler content is 100% by volume is calculated by extrapolation, and this is defined as the "dielectric constant of the entire inorganic filler."

[0079] From the viewpoint of high dielectric constant, the high dielectric inorganic filler preferably contains a titanium-based inorganic filler containing titanium element. Examples of titanium-based inorganic fillers include barium titanate, calcium titanate, strontium titanate, zinc titanate zirconate, and titanium oxide. Among these, barium titanate, calcium titanate, and strontium titanate are preferred. Among these, calcium titanate is preferred from the viewpoint of low dielectric loss tangent.

[0080] The average particle size of the highly dielectric inorganic filler is preferably 0.1 μm to 100 μm, and more preferably 0.5 μm to 30 μm.

[0081] The average particle size of the highly dielectric inorganic filler can be measured as follows: The resin composition is placed in a crucible and left at 800°C for 4 hours to be incinerated. The particle size distribution of the resulting ash is determined using a laser diffraction / scattering particle size distribution analyzer (e.g., HORIBA, Ltd., LA920), and the average particle size of the inorganic filler can be determined from the particle size distribution as the volume average particle size (D50).

[0082] The highly dielectric inorganic filler may have one peak or two or more peaks in the particle size distribution. When the particle size distribution has two or more peaks, it is preferable that the peaks are at 1.0 μm or less and 1.5 μm or more, respectively, from the viewpoint of improving flowability.

[0083] The shape of the highly dielectric inorganic filler is not particularly limited, and examples thereof include spherical, elliptical, irregular, etc. The highly dielectric inorganic filler may also be crushed.

[0084] The resin composition may contain fillers other than the high-dielectric inorganic filler. The type of other filler is not particularly limited. Specific examples of the material of the other filler include inorganic materials such as 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. An inorganic filler having a flame-retardant effect may also be used. Examples of inorganic fillers having a flame-retardant effect include aluminum hydroxide, magnesium hydroxide, composite metal hydroxides such as magnesium-zinc composite hydroxide, and zinc borate. One type of the other filler may be used alone, or two or more types may be used in combination.

[0085] Among these, the other filler preferably contains at least one selected from the group consisting of silica particles and alumina particles, from the viewpoints of being spherical, capable of improving the filling rate, having a dielectric loss tangent lower than that of the specific inorganic filler, and being able to control the dielectric properties of the composite material. The other filler may contain only one of silica particles and alumina particles, or may contain both silica particles and alumina particles. When the other filler contains at least one selected from the group consisting of silica particles and alumina particles, the total content of the silica particles and alumina particles is preferably 10% by volume to 90% by volume, more preferably 20% by volume to 80% by volume, and even more preferably 35% by volume to 60% by volume, based on the total inorganic filler.

[0086] The other filler preferably contains alumina particles, from the viewpoint of increasing the fluidity of the resin composition and reducing the dielectric loss tangent of the composite material. When the other filler contains alumina particles, the content of the alumina particles is preferably 10% by volume to 90% by volume, more preferably 20% by volume to 80% by volume, and even more preferably 35% by volume to 60% by volume, based on the total volume of the inorganic filler.

[0087] The volume average particle size of the other filler is not particularly limited. The volume average particle size of the other filler is preferably 0.2 μm to 100 μm, and more preferably 0.5 μm to 50 μm. When the volume average particle size of the other filler is 0.2 μm or more, the increase in viscosity of the resin composition tends to be further suppressed. When the volume average particle size of the other filler is 100 μm or less, the filling property of the resin composition tends to be further improved.

[0088] The average particle size of the other inorganic filler can be determined by placing the resin composition in a crucible and leaving it at 800°C for 4 hours to incinerate it. The resulting ash is observed with an SEM, separated by shape, and the particle size distribution is determined from the observed image. The volume average particle size of the other filler can then be determined from the particle size distribution as the volume average particle size (D50). The other filler may be a mixture of two or more fillers with different volume average particle sizes.

[0089] The shape of the other filler is not particularly limited, and examples thereof include spherical, elliptical, and irregular shapes. The other filler may also be crushed. From the viewpoint of improving the fluidity of the resin composition, the shape of the other filler is preferably spherical.

[0090] From the viewpoint of controlling the fluidity and strength of the cured product of the resin composition, the total content of the inorganic filler contained in the resin composition is preferably 40% by volume to 90% by volume of the total resin composition, more preferably 40% by volume to 85% by volume, even more preferably 45% by volume to 85% by volume, particularly preferably 50% by volume to 82% by volume, and extremely preferably 55% by volume to 80% by volume.

[0091] The content (volume %) of inorganic filler in a resin composition can be determined by the following method. A thin slice sample of the cured resin composition is imaged using a scanning electron microscope (SEM). An arbitrary area S is identified in the SEM image, and the total area A of the inorganic fillers contained in area S is determined. The total area A of the inorganic fillers is divided by area S to convert it to a percentage (%), and this value is used as the content (volume %) of inorganic filler in the resin composition. Area S is set to an area sufficiently large compared to the size of the inorganic filler. For example, it is set to a size that contains 100 or more inorganic fillers. Area S may be the sum of multiple cross sections. The inorganic filler may have a bias in its presence in the direction of gravity when the resin composition is cured. In this case, when imaging with an SEM, the entire cured product is imaged in the direction of gravity, and the area S containing the entire cured product in the direction of gravity is determined.

[0092] The relative dielectric constant of the entire inorganic filler at 10 GHz is, for example, in the range of 80 or less, and from the viewpoint of suppressing dielectric loss, it is preferably 50 or less, more preferably 40 or less, and even more preferably 30 or less. From the viewpoint of miniaturizing electronic components such as antennas, the relative dielectric constant of the entire inorganic filler at 10 GHz is preferably 5 or more, more preferably 10 or more, and even more preferably 15 or more. From the viewpoint of suppressing dielectric loss and miniaturizing electronic components such as antennas, the relative dielectric constant of the entire inorganic filler at 10 GHz is preferably 5 to 50, more preferably 10 to 40, and even more preferably 15 to 30.

[0093] The relative dielectric constant of the entire inorganic filler at 20 GHz is, for example, in the range of 85 or less, and from the viewpoint of suppressing dielectric loss, it is preferably 55 or less, more preferably 45 or less, and even more preferably 35 or less. From the viewpoint of miniaturizing electronic components such as antennas, the relative dielectric constant of the entire inorganic filler at 20 GHz is preferably 6 or more, more preferably 2 or more, and even more preferably 16 or more. From the viewpoint of suppressing dielectric loss and miniaturizing electronic components such as antennas, the relative dielectric constant of the entire inorganic filler at 20 GHz is preferably 6 to 55, more preferably 12 to 45, and even more preferably 16 to 35.

[0094] Here, the relative dielectric constant of the entire inorganic filler is determined, for example, as follows. Specifically, three or more measurement resin compositions containing the inorganic filler to be measured and a specific curable resin, but with different inorganic filler contents, and a measurement resin composition containing the specific curable resin but without the inorganic filler, are prepared. Examples of measurement resin compositions containing the inorganic filler to be measured and the specific curable resin include a measurement resin composition containing a biphenylaralkyl epoxy resin, a phenolic curing agent that is a phenolaralkyl phenolic resin, a curing accelerator containing an organic phosphine, and the inorganic filler to be measured. Examples of three or more measurement resin compositions with different inorganic filler contents include measurement resin compositions with inorganic filler contents of 10 vol%, 20 vol%, and 30 vol% relative to the entire measurement resin composition. Each of the prepared measurement resin compositions is compression molded under conditions of a mold temperature of 175°C, a molding pressure of 6.9 MPa, and a curing time of 600 seconds, to obtain a measurement cured product. The dielectric constant of each of the obtained cured products for measurement at a measurement frequency (10 GHz, 20 GHz, etc.) is measured, and a graph is prepared by plotting the inorganic filler content on the horizontal axis and the measured dielectric constant on the vertical axis. From the obtained graph, a linear approximation is performed using the least squares method, and the dielectric constant when the inorganic filler content is 100% by volume is determined by extrapolation, and this is defined as the "dielectric constant of the entire inorganic filler."

[0095] [Various Additives] In addition to the components described above, the resin composition may contain various additives such as a curing accelerator, a coupling agent, an ion exchanger, a release agent, a flame retardant, a colorant, and a stress relaxation agent, as exemplified below. The resin composition of the present embodiment may contain various additives known in the technical field as needed, in addition to the additives exemplified below.

[0096] (Curing Accelerator) The resin composition may contain a curing accelerator as needed. The type of curing accelerator is not particularly limited and can be selected depending on the type of epoxy resin or curing agent, the desired properties of the resin composition, etc.

[0097] Examples of the curing accelerator 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, 2-ethyl-4-methylimidazole, and 2-heptadecylimidazole; derivatives of the cyclic amidine compounds; phenol novolac salts of the cyclic amidine compounds or their derivatives; and the addition of maleic anhydride to these compounds, 1,4-benzoquinone, 2,5-toluquinone, 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 obtained by adding a compound having a π bond, such as a quinone compound or diazophenylmethane; cyclic amidinium compounds such as the tetraphenylborate salt of DBU, the tetraphenylborate salt of DBN, the tetraphenylborate salt of 2-ethyl-4-methylimidazole, and the 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 such as ethylphosphine and phenylphosphine, secondary phosphines such as dimethylphosphine and diphenylphosphine, and tertiary phosphines such as 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, alkyldiarylphosphine, trinaphthylphosphine, and tris(benzyl)phosphine; phosphine compounds such as complexes of the organic phosphines with organic borons; and the organic phosphines or the phosphine compounds, which may be combined with maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone. quinone compounds such as 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, and anthraquinone, and compounds having intramolecular polarization obtained by adding a compound having a π bond such as diazophenylmethane; a compound having intramolecular polarization, which is obtained by reacting a halogenated phenol compound such as 1-iodophenol, 2-iodophenol, 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, or 4-bromo-4'-hydroxybiphenyl with the halogenated phenol compound, followed by a dehydrohalogenation step;Examples of suitable curing accelerators include tetra-substituted phosphonium compounds such as tetraphenylphosphonium, tetraphenylborate salts of tetra-substituted phosphonium such as tetraphenylphosphonium tetra-p-tolylborate, and salts of tetra-substituted phosphonium with phenolic compounds; salts of tetraalkylphosphonium with partial hydrolysates of aromatic carboxylic acid anhydrides; phosphobetaine compounds; and adducts of phosphonium compounds with silane compounds. These curing accelerators may be used alone or in combination of two or more. Among these, particularly suitable curing accelerators include triphenylphosphine, an adduct of triphenylphosphine with a quinone compound, an adduct of tributylphosphine with a quinone compound, and an adduct of tri-p-tolylphosphine with a quinone compound.

[0098] When the resin composition contains a curing accelerator, the amount thereof 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 (total amount of epoxy resin and curing agent). When the amount of the curing accelerator is 0.1 part by mass or more per 100 parts by mass of the resin component, the composition tends to cure well in a short time. When the amount of the 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.

[0099] (Coupling Agent) The resin composition may contain a coupling agent. From the viewpoint of improving the adhesion between the resin component and the inorganic filler, the resin composition preferably contains a coupling agent. Examples of the coupling agent include known coupling agents such as silane-based compounds such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, vinylsilane, and disilazane, titanium-based compounds, aluminum chelate-based compounds, and aluminum / zirconium-based compounds.

[0100] When the resin composition contains a coupling agent, the amount of the coupling agent is preferably 0.05 to 5 parts by mass, and more preferably 0.1 to 2.5 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, adhesion to the frame tends to be further improved. When the amount of the coupling agent is 5 parts by mass or less per 100 parts by mass of the inorganic filler, moldability of the package tends to be further improved.

[0101] (Ion exchanger) The resin composition may contain an ion exchanger. The resin composition preferably contains an ion exchanger from the viewpoint of improving the moisture resistance and high-temperature storage characteristics of an electronic component device including an encapsulated electronic component. The ion exchanger is not particularly limited, and conventionally known ion exchangers 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 alone or in combination of two or more. Among these, hydrotalcites represented by the following general formula (A) are preferred.

[0102] Mg （１－Ｘ） Al Ｘ (OH) ２ (CO ３ ) Ｘ／２ ・mH ２ O ……(A) (0<X≦0.5, m is a positive number)

[0103] When the resin composition contains an ion exchanger, the content thereof is not particularly limited as long as it is an amount sufficient to capture ions such as halogen ions. For example, the content of the ion exchanger is preferably 0.1 to 30 parts by mass, and more preferably 1 to 10 parts by mass, per 100 parts by mass of the resin component (the total amount of the epoxy resin and the curing agent).

[0104] (Mold Release Agent) The resin composition may contain a mold release agent from the viewpoint of obtaining good mold releasability during molding. There are no particular limitations on the mold release agent, and conventionally known ones 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. One type of mold release agent may be used alone, or two or more types may be used in combination.

[0105] When the resin composition contains a release agent, the amount thereof is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the resin component (total amount of epoxy resin and curing agent). When the amount of the release agent is 0.01 part by mass or more per 100 parts by mass of the resin component, sufficient release properties tend to be obtained. When the amount is 10 parts by mass or less, better adhesion tends to be obtained.

[0106] (Flame retardant) The resin composition may contain a flame retardant. There are no particular limitations on the flame retardant, and conventionally known flame retardants can be used. Specific examples include organic or inorganic compounds containing halogen atoms, antimony atoms, nitrogen atoms, or phosphorus atoms, and metal hydroxides. The flame retardants may be used alone or in combination of two or more.

[0107] When the resin composition contains a flame retardant, the amount thereof is not particularly limited as long as it is an amount sufficient to obtain the desired flame retardant effect. For example, the amount 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 (total amount of the epoxy resin and the curing agent).

[0108] (Colorant) The resin composition may contain a colorant. Examples of the colorant include known colorants such as carbon black, organic dyes, organic pigments, titanium oxide, red lead, and red iron oxide. The content of the colorant can be appropriately selected depending on the purpose, etc. The colorant may be used alone or in combination of two or more.

[0109] (Stress Relaxant) The resin composition may contain a stress relaxation agent. By including a stress relaxation agent, warpage of the package and the occurrence of package cracks can be further reduced. Examples of stress relaxation agents include commonly used known stress relaxation agents (flexibilizers). Specific examples include thermoplastic elastomers such as silicone-based, styrene-based, olefin-based, urethane-based, polyester-based, polyether-based, polyamide-based, and polybutadiene-based elastomers; rubber particles such as NR (natural rubber), NBR (acrylonitrile-butadiene rubber), acrylic rubber, urethane rubber, and silicone powder; and rubber particles having a core-shell structure such as methyl methacrylate-styrene-butadiene copolymer (MBS), methyl methacrylate-silicone copolymer, and methyl methacrylate-butyl acrylate copolymer. One type of stress relaxation agent may be used alone, or two or more types may be used in combination. Among stress relaxation agents, silicone-based stress relaxation agents are preferred. Examples of silicone-based stress relaxation agents include those having an epoxy group, those having an amino group, and those modified with polyether, and silicone compounds such as silicone compounds having an epoxy group and polyether-based silicone compounds are more preferred.

[0110] When the resin composition contains a stress relaxation agent, the amount thereof is, for example, preferably 1 part by mass to 30 parts by mass, and more preferably 2 parts by mass to 20 parts by mass, per 100 parts by mass of the resin component (the total amount of the epoxy resin and the curing agent).

[0111] The resin composition preferably has a solvent content of 5% by mass or less, more preferably 1% by mass or less, even more preferably 0.5% by mass or less, and particularly preferably contains substantially no solvent (0% by mass).

[0112] (Method for preparing resin composition) The method for preparing the resin composition is not particularly limited. A common method includes thoroughly mixing predetermined amounts of components using a mixer or the like, melt-kneading the components using a mixing roll, extruder, or the like, cooling, and pulverizing the mixture. More specifically, for example, a method includes stirring and mixing predetermined amounts of the components described above, kneading the mixture using a kneader, roll, extruder, or the like that has been preheated to 70°C to 140°C, cooling, and pulverizing the mixture.

[0113] The resin composition in this embodiment is preferably solid at room temperature and normal pressure (for example, 25°C, atmospheric pressure). When the resin composition is solid, the shape is not particularly limited, and examples include powder, granules, tablets, etc. When the resin composition is in tablet form, it is preferable that the dimensions and mass of the tablet-shaped resin composition be such that they are suitable for the molding conditions of the package, from the viewpoint of handleability.

[0114] (Characteristics of Resin Composition) —Dielectric Constant— The resin composition is compression molded under conditions of a mold temperature of 175°C, a molding pressure of 6.9 MPa, and a curing time of 600 seconds, and then post-cured at 175°C for 6 hours. The cured product has a dielectric constant at 10 GHz of, for example, 3 to 45, and from the viewpoint of miniaturizing electronic components such as antennas, preferably 7 to 40, and more preferably 8 to 25.

[0115] The dielectric constant of the cured product at 20 GHz is, for example, 3 to 50, preferably 7 to 45, and more preferably 8 to 30, from the viewpoint of miniaturizing electronic components such as antennas.

[0116] The measurement of the relative dielectric constant is carried out at a temperature of 25±3° C. using a dielectric constant measuring device (for example, Agilent Technologies, product name "Network Analyzer N5227A").

[0117] -Dielectric loss tangent- The resin composition is compression molded under conditions of a mold temperature of 175°C, a molding pressure of 6.9 MPa, and a curing time of 600 seconds, and then post-cured at 175°C for 6 hours to obtain a cured product having a dielectric loss tangent at 10 GHz of, for example, 0.020 or less, and from the viewpoint of reducing transmission loss, preferably 0.018 or less, and more preferably 0.015 or less. The lower limit of the dielectric loss tangent at 10 GHz of the cured product is not particularly limited, and for example, can be 0.002 or more.

[0118] The dielectric loss tangent of the cured product at 20 GHz is, for example, 0.030 or less, and from the viewpoint of miniaturization of electronic components such as antennas, is preferably 0.025 or less, and more preferably 0.020 or less. The lower limit of the dielectric loss tangent of the cured product at 20 GHz is not particularly limited, and is, for example, 0.005 or more.

[0119] - Flexural Strength - A test piece having a size of 4.0 mm x 10.0 mm x 80 mm is prepared from the resin composition using a transfer molding machine under conditions of a mold temperature of 175°C, a molding pressure of 6.9 MPa, and a curing time of 300 seconds, and post-curing is performed for 6 hours at 175°C. The flexural strength of the cured product obtained is preferably 70 MPa or more, more preferably 80 MPa or more, and even more preferably 100 MPa or more. There is no particular upper limit to the flexural strength, but it may be 200 MPa or less or 180 MPa or less.

[0120] The bending strength is measured by subjecting the cured product to a bending test at a temperature of 25°C using a Tensilon universal testing machine (for example, Instron Corporation, product name "Instron 5948"), creating a bending stress-displacement curve using the following formula (A), and taking the maximum stress as the bending strength (MPa).

[0121] σ=3FL / 2bh ２ Formula (A) σ: bending stress (MPa) F: bending load (N) L: distance between supports (mm) b: test piece width (mm) h: test piece thickness (mm)

[0122] -Spiral Flow- When the resin composition is molded using a spiral flow measurement mold conforming to EMMI-1-66 under conditions of a mold temperature of 175°C, a molding pressure of 6.9 MPa, and a curing time of 120 seconds, the flow distance (hereinafter also referred to as "spiral flow") is preferably 60 cm or more, more preferably 80 cm or more, and even more preferably 95 cm or more. The upper limit of the spiral flow is not particularly limited, and may be, for example, 200 cm or less.

[0123] The gel time of the resin composition at 175°C is preferably 30 to 90 seconds, and more preferably 40 to 60 seconds. The gel time at 175°C is measured as follows. Specifically, a 3 g sample of the resin composition is measured at 175°C using a Curelastometer (for example, manufactured by JSR Trading Co., Ltd.), and the time until the torque curve rises is measured as the gel time (sec).

[0124] (Uses of Resin Composition) The resin composition of the present disclosure can be applied to, for example, the manufacture of electronic component devices, particularly high-frequency devices, as described below. The resin composition is particularly suitable for use in antenna-in-package (AiP) applications in high-frequency devices, in which an antenna disposed on a support member is encapsulated with the resin composition.

[0125] An electronic component device according to an embodiment of the present disclosure includes a support member, an electronic component disposed on the support member, and a cured product of the resin composition encapsulating the electronic component. Examples of the electronic component device include a support member such as a lead frame, a pre-wired tape carrier, a wiring board, glass, a silicon wafer, or an organic substrate, on which electronic components (e.g., active elements such as semiconductor chips, transistors, diodes, and thyristors, passive elements such as capacitors, resistors, and coils, and antennas) are mounted, and the resulting electronic component region is encapsulated with the resin composition (e.g., a high-frequency device).

[0126] The type of the support member is not particularly limited, and a support member generally used in the manufacture of electronic component devices can be used. The electronic component may include an antenna, or may include an antenna and an element other than an antenna. The antenna is not limited as long as it functions as an antenna, and may be an antenna element or wiring.

[0127] In addition, in the electronic component device, if necessary, another electronic component may be disposed on the surface of the support member opposite to the surface on which the electronic component is disposed. The other electronic component may be encapsulated with the resin composition described above, with another resin composition, or may not be encapsulated.

[0128] (Method for manufacturing an electronic component device) A method for manufacturing an electronic component device according to one embodiment of the present disclosure includes the steps of placing electronic components on a support member and encapsulating the electronic components with the resin composition described above. The method for carrying out each of the above steps is not particularly limited, and can be performed using a general method. Furthermore, the types of support member and electronic components used in manufacturing the electronic component device are not particularly limited, and support members and electronic components commonly used in manufacturing electronic component devices can be used.

[0129] Methods for encapsulating electronic components using the resin composition include low-pressure transfer molding, injection molding, compression molding, etc. Among these, low-pressure transfer molding is the most common.

[0130] The above-described embodiment will be specifically described below using examples, but the scope of the above-described embodiment is not limited to these examples.

[0131] <Preparation of Resin Composition> The components shown below were mixed in the blending ratios (parts by mass) shown in Table 1 to prepare resin compositions of Examples and Comparative Examples. This resin composition was solid at room temperature and normal pressure. Table 1 also shows the content of the inorganic filler relative to the entire resin composition ("Vf" (volume %) in the table). Table 1 also shows the "equivalent ratio," which is expressed as "(equivalent number of ester groups of the active ester compound + equivalent number of imide groups of the cyclic carbodiimide compound) / equivalent number of epoxy groups of the epoxy resin."

[0132] Epoxy resin 1: biphenyl aralkyl type epoxy resin, epoxy equivalent 274 g / eq (Nippon Kayaku Co., Ltd., product name "NC-3000") Epoxy resin 2: biphenyl type epoxy resin, epoxy equivalent 192 g / eq (Mitsubishi Chemical Corporation, product name "YX-4000") Epoxy resin 3: orthocresol novolac type epoxy resin, epoxy equivalent 200 g / eq (DIC Corporation, "N500P-2")

[0133] Curing agent: Active ester compound, DIC Corporation, product name "EXB-8"

[0134] Cyclic carbodiimide compound (imide equivalent weight 256 g / eq, Teijin Limited, product name "TCC-FP10M")

[0135] Curing accelerator: Adduct of triphenylphosphine and 1,4-benzoquinone Coupling agent: N-phenyl-3-aminopropyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd., product name "KBM-573") Mold release agent: Montan acid ester wax (Clariant Japan Co., Ltd., product name "HW-E") Colorant: Carbon black

[0136] Inorganic filler 1 (high dielectric): calcium titanate particles, volume average particle size: 0.2 μm, shape: polyhedron Inorganic filler 2 (high dielectric): calcium titanate particles, volume average particle size: 6 μm, shape: polyhedron Inorganic filler 3: alumina particles, volume average particle size: 7 μm, shape: spherical

[0137] The volume-average particle size of each inorganic filler was a value obtained by the following measurement. Specifically, the inorganic filler was first added to a dispersion medium (water) in an amount ranging from 0.01% by mass to 0.1% by mass, and the mixture was dispersed in a bath-type ultrasonic cleaner for 5 minutes. Five milliliters of the resulting dispersion was poured into a cell, and the particle size distribution was measured at 25°C using a laser diffraction / scattering particle size distribution analyzer (HORIBA, Ltd., LA920). The particle size at an integrated value of 50% (volume basis) in the resulting particle size distribution was taken as the volume-average particle size.

[0138] <Evaluation of Resin Composition> (Dielectric Constant and Dielectric Loss Tangent) The resin composition was charged into a vacuum hand press and molded under the conditions of a mold temperature of 175°C, a molding pressure of 6.9 MPa, and a curing time of 600 seconds. Post-curing was carried out at 175°C for 6 hours to obtain a cured product having a length of 0 mm, a width of 0.5 mm, and a thickness of 0.5 mm. This cured product was used as a test piece and the dielectric constant (Dk) and dielectric loss tangent (Df) were measured at a temperature of 25±3°C, 10 GHz, and 20 GHz using a dielectric constant measuring device (Agilent Technologies, product name "Network Analyzer N5227A"). The results are shown in Table 1.

[0139] (Fluidity: Spiral Flow) Using a spiral flow measurement mold conforming to EMMI-1-66, the resin composition was molded under conditions of a mold temperature of 175°C, a molding pressure of 6.9 MPa, and a curing time of 120 seconds, and the flow distance (cm) was determined. The results are shown in Table 1.

[0140] (Gel Time) Measurement was carried out at a temperature of 175° C. using a Curelastometer manufactured by JSR Trading Co., Ltd. for 3 g of the resin composition, and the time until the torque curve rose was taken as the gel time (seconds). The results are shown in Table 1.

[0141] (Flexural Modulus) The resin composition was subjected to a transfer molding machine under conditions of a mold temperature of 175 ° C, a molding pressure of 6.9 MPa, and a curing time of 300 seconds to prepare a test piece having a shape of 4.0 mm x 10.0 mm x 80 mm. Then, post-curing was performed at 175 ° C for 6 hours. The obtained cured product was subjected to a three-point support bending test in accordance with JIS-K-7171 (2016) using a Tensilon universal testing machine (Instron Corporation, product name "Instron 5948") at 25 ° C., and the flexural modulus E1 (GPa) of the test piece at 25 ° C. was determined. The flexural modulus was calculated using the following formula. In the formula, E is the flexural modulus (GPa), P is the load cell value (N), y is the displacement (mm), l is the span = 64 mm, w is the test piece width = 12.7 mm, and h is the test piece thickness = 4 mm.

[0142] (Bending Strength) The resin composition was charged into a transfer molding machine and molded into a 4.0 mm x 10.0 mm x 80 mm rectangular parallelepiped at a mold temperature of 175 ° C, a molding pressure of 6.9 MPa, and a curing time of 300 seconds. Post-curing was performed at 175 ° C for 6 hours to prepare a test specimen for bending strength evaluation. Using this test specimen, a bending test was performed using a Tensilon universal testing machine (Instron 5948, Instron Corporation) under conditions of a support distance of 64 mm, a crosshead speed of 10 mm / min, and a temperature of 25 ° C. Using the measured results, a bending stress-displacement curve was created from the above formula (A), and the maximum stress was taken as the bending strength (MPa). The results are shown in Table 1.

[0143] (Glass transition temperature) The resin composition was molded into a rectangle with a short side of 10 mm, a long side of 40 mm, and a thickness of 4 mm using a transfer molding machine under conditions of a mold temperature of 175 ° C, a molding pressure of 6.9 MPa, and a curing time of 300 seconds. Then, post-curing was performed at 175 ° C for 6 hours to prepare a test piece for glass transition temperature. Using this test piece, dynamic viscoelasticity measurement was performed using a viscoelasticity measuring device (TA Instruments, product name "RSA3") under the following conditions: test mode: three-point bending mode, measurement temperature: 25 ° C to 330 ° C, heating rate: 10 ° C / min, test frequency: 1 Hz. The temperature at which tan δ was maximized was determined as the glass transition temperature. The results are shown in Table 1.

[0144]

[0145] As shown in Table 1, when Examples 1 and 2, which use the same epoxy resin, are compared with Comparative Example 1, the cured products obtained from the resin compositions of Examples 1 and 2 maintained equally high relative permittivity, had lower dielectric dissipation factor, and exhibited significantly improved flexural strength at both 10 GHz and 20 GHz compared to the cured product obtained from the resin composition of Comparative Example 1. When Example 3, which uses the same epoxy resin, is compared with Comparative Example 2, the cured product obtained from the resin composition of Example 3 maintained equally high relative permittivity, had lower dielectric dissipation factor, and exhibited significantly improved flexural strength at both 10 GHz and 20 GHz compared to the cured product obtained from the resin composition of Comparative Example 2. Furthermore, when Examples 1 and 2 are compared with Comparative Example 1, and when Example 3 is compared with Comparative Example 2, the cured products obtained from the resin compositions of the Examples had higher glass transition temperatures than the cured products obtained from the resin compositions of the Comparative Examples.

[0146] The disclosure of Japanese Patent Application No. 2023-119483 is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards in this disclosure are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A resin composition containing an epoxy resin, an active ester compound as a curing agent, a highly dielectric inorganic filler, and a cyclic carbodiimide compound.

2. The resin composition according to claim 1, wherein the content of the cyclic carbodiimide compound is 1 part by mass or more per 100 parts by mass of the epoxy resin.

3. A resin composition according to claim 1 or claim 2, wherein the content of the cyclic carbodiimide compound is 50 parts by mass or less per 100 parts by mass of the epoxy resin.

4. A resin composition according to claim 1 or 2, wherein the ratio of the total amount of the functional group equivalent number of the entire curing agent and the imide group equivalent number of the cyclic carbodiimide compound to the epoxy group equivalent number of the epoxy resin [(functional group equivalent number of the entire curing agent + imide group equivalent number of the cyclic carbodiimide compound) / epoxy group equivalent number of the epoxy resin] is 0.51 to 2.

20.

5. The resin composition according to claim 1 or 2, wherein the highly dielectric inorganic filler includes a titanium-based inorganic filler.

6. The resin composition according to claim 1 or 2, further comprising at least one selected from the group consisting of a curing accelerator, a coupling agent, an ion exchanger, a release agent, a flame retardant, a colorant, and a stress relaxation agent.

7. The resin composition according to claim 1 or 2, which is used in a high-frequency device.

8. The resin composition according to claim 1 or 2, which is used for an antenna-in-package.

9. An electronic component device comprising: a support member; an electronic component arranged on the support member; and a cured product of the resin composition according to claim 1 or 2 encapsulating the electronic component.

10. The electronic component device of claim 9, wherein the electronic component includes an antenna.

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