Epoxy resin composition, cured product, sealing material, semiconductor package, and method for producing epoxy resin composition

Abstract

To provide an epoxy resin composition that exhibits superior injectability without clogging.SOLUTION: An epoxy resin composition comprises an epoxy resin and inorganic particles, and the inorganic particles have a solubility parameter (SP value) of 18 or more and 28 or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an epoxy resin composition, a cured product, an encapsulant, a semiconductor package, and a method for producing an epoxy resin composition. [Background technology]

[0002] Epoxy resins have been used in a wide range of applications, such as coating materials, electrical and electronic insulating materials, and adhesives, because their cured products have excellent performance in terms of mechanical properties, electrical properties, thermal properties, chemical resistance, adhesive properties, and the like.

[0003] Epoxy resin compositions used as electrical and electronic insulating materials typically contain inorganic particles as fillers to adjust their coefficient of thermal expansion (CTE). The primary purpose is to reduce the CTE mismatch between the substrate and the epoxy resin, thereby preventing mechanical stress during thermal cycling. This prevents mechanical and electrical defects in electronic devices, such as cracking and peeling of the substrate.

[0004] Meanwhile, as electronic devices have become more sophisticated in recent years, the demands placed on semiconductor devices used in such electronic devices have become more diverse. For example, as semiconductor devices have become smaller and semiconductor chips have become larger, the demands placed on each application have become more diverse. In addition, in recent years, as a high-integration technology, a layer used to establish electrical continuity between circuits on the front and back sides using through electrodes, i.e., an interposer, has been widely used (see, for example, Patent Documents 1 to 3).

[0005] In the semiconductor device, when gaps such as the gap between an electronic component such as a semiconductor chip and a circuit board, the gap between an electronic component and an interposer, and the gap between an interposer and a circuit board are reinforced with a resin (sealant), a technique has been adopted in which a liquid epoxy resin composition is supplied after solder bonding and then cured. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-175009 [Patent Document 2] Japanese Patent Application Laid-Open No. 2015-507360 [Patent Document 3] Japanese Patent Application Laid-Open No. 2016-58627 Summary of the Invention [Problem to be solved by the invention]

[0007] In recent years, as semiconductor devices have become thinner, the pitch and gap between solder joints have become narrower. Meanwhile, the surface area of ​​semiconductor elements has also increased. When using narrow gaps or large semiconductor elements, it is increasingly necessary to thoroughly penetrate the epoxy resin into the gap between the semiconductor element or interposer and the substrate, etc. However, the techniques disclosed in Patent Documents 1 to 3 have the problem that the epoxy resin does not sufficiently penetrate into small voids due to clogging caused by filler aggregation and the high viscosity of the epoxy resin, and there is still room for improvement in terms of filling properties.

[0008] Therefore, an object of the present invention is to provide an epoxy resin composition which is free from clogging and has excellent injectability. [Means for solving the problem]

[0009] As a result of extensive investigations, the present inventors have found that the above-mentioned problems of the conventional art can be solved by setting the solubility parameter (SP value) of the inorganic particles in an epoxy resin composition containing an epoxy resin and inorganic particles to a specific numerical range, and have thus completed the present invention. That is, the present invention is as follows.

[0010] [1] An epoxy resin composition containing an epoxy resin and inorganic particles, The epoxy resin composition, wherein the inorganic particles have a solubility parameter (SP value) of 18 or more and 28 or less. [2] The epoxy resin includes a p-aminophenol type epoxy resin. The epoxy resin composition according to [1] above. [3] Further containing a curing agent, the number of aggregates in a 700 μm × 500 μm observation area of ​​the cured product of the epoxy resin composition is 5 or less; The epoxy resin composition according to [1] or [2] above. [4] The surface element ratio C / Si of the inorganic particles is 0.1 or more and 0.7 or less. The epoxy resin composition according to any one of [1] to [3] above. [5] The inorganic particles have an average particle size of 0.01 μm or more and 10.0 μm or less. The epoxy resin composition according to any one of [1] to [4] above. [6] The specific surface area of ​​the inorganic particles is 2m 2 / g or more 24m 2 / g or less, The epoxy resin composition according to any one of [1] to [5] above. [7] The content of the inorganic particles is 65% by mass or more and 85% by mass or less. The epoxy resin composition according to any one of [1] to [6] above. [8] The epoxy resin composition according to any one of [1] to [7] above, wherein the inorganic particles are surface-treated with a surface treatment agent represented by the following formula (1) or the following formula (2):

[0011] [ka]

[0012] [ka]

[0013] In formula (1), m is an integer of 3 or more, and A represents one group selected from the group consisting of an epoxy group, an amino group, a mercapto group, a vinyl group, and a ureido group. In formula (2), n is an integer of 8 or more, and A represents one group selected from the group consisting of an epoxy group, an amino group, a mercapto group, a vinyl group, and a ureido group.

[0014] [9] An aromatic amine compound (A-1) represented by the following formula (4) or the following formula (5), an aromatic amine adduct (A-2) which is a reaction product of the aromatic amine compound (A-1) and a reactive compound having a functional group capable of reacting with the aromatic amine compound (A-1), Further containing The epoxy resin composition according to any one of [1] to [8] above.

[0015] [ka]

[0016] In formula (4), Rγ and Rδ each independently represent a monovalent organic group having 1 to 20 carbon atoms or a halogen group, c and d each independently represent an integer of 1 to 4, and Y represents a divalent organic group or a single bond.

[0017] [ka]

[0018] In formula (5), Rε represents a monovalent organic group having 1 to 20 carbon atoms or a halogen group, and e represents an integer of 1 to 4.

[0019]

[10] Further containing a curing agent, The viscosity increase rate after leaving it at 110°C for 60 minutes is 1.0 to 40.0 times, The epoxy resin composition according to any one of [1] to [9] above.

[11] A cured product of the epoxy resin composition according to any one of [1] to

[10] above.

[12] There are five or fewer aggregates in the 700 μm × 500 μm observation area. The cured product according to

[11] above.

[13] A sealing material comprising the cured product according to

[11] or

[12] above.

[14] A semiconductor package comprising the encapsulant described in

[13] .

[15] (a) modifying the surfaces of inorganic particles by mixing the inorganic particles with a surface treatment agent in a first solvent; (b) removing the surface treatment agent free in the first solvent; (c) a step of dispersing the inorganic particles in a second solvent to obtain an inorganic particle dispersion; a step (d) of mixing the inorganic particle dispersion liquid with an epoxy resin to obtain a mixed liquid; (e) placing the mixture under reduced pressure to remove the second solvent; The following steps are carried out in order: In the steps (a) to (e), the inorganic particles always coexist with a solvent and / or an epoxy resin. A method for producing an epoxy resin composition.

[16] The method for producing an epoxy resin composition according to

[15] above, wherein in the steps (a) to (c), the surface element ratio C / Si of the inorganic particles is controlled to 0.1 or more and 0.7 or less.

[17] The epoxy resin includes a p-aminophenol type epoxy resin. A method for producing the epoxy resin composition according to

[15] or

[16] above.

[18] In the step (e), The temperature of the mixture is 150°C or less. A method for producing an epoxy resin composition according to any one of

[15] to

[17] above.

[19]

[19] The method for producing an epoxy resin composition according to any one of

[15] to

[18] , wherein the inorganic particles have a solubility parameter (SP value) that differs by 0.1 or more before and after the step (a).

[20] In the step (c), Do not stir with a high shear force of 4.5 N·m or more. A method for producing an epoxy resin composition according to any one of

[15] to

[19] above. 〔twenty one〕 After the step (e), an aromatic amine compound (A-1) represented by the following formula (4) or formula (5) is added: an aromatic amine adduct (A-2) which is a reaction product of the aromatic amine compound (A-1) and a reactive compound having a functional group capable of reacting with the aromatic amine compound (A-1); A hardener comprising: A method for producing an epoxy resin composition according to any one of

[15] to

[20] above.

[0020] [ka]

[0021] In formula (4), Rγ and Rδ each independently represent a monovalent organic group having 1 to 20 carbon atoms or a halogen group, c and d each independently represent an integer of 1 to 4, and Y represents a divalent organic group or a single bond.

[0022] [ka]

[0023] In formula (5), Rε represents a monovalent organic group having 1 to 20 carbon atoms or a halogen; [Effects of the Invention]

[0024] According to the present invention, an epoxy resin composition that is free from clogging and has excellent injectability can be provided. DETAILED DESCRIPTION OF THE INVENTION

[0025] Hereinafter, an embodiment of the present invention (hereinafter referred to as "the present embodiment") will be described in detail for the purpose of illustrating the present invention, but the present invention is not limited to the present embodiment.

[0026] [Epoxy resin composition] The epoxy resin composition of the present embodiment contains an epoxy resin and inorganic particles, and the solubility parameter (SP value) of the inorganic particles is 18 or more and 28 or less. According to the above-mentioned method, an epoxy resin composition having excellent injectability without clogging can be obtained.

[0027] (SP value) In this specification, the solubility parameter (SP value) refers to the Hansen solubility parameter, which can be determined using the Hansen dissolved sphere method. That is, the SP value of inorganic particles can be determined by dispersing small amounts of inorganic particles in multiple solvents with different SP values, and using HSPiP, an HSP calculation software, to determine the SP value of inorganic particles. Two solvents that show values ​​close to the particle size d50 of the inorganic particles are considered "compatible" and the others are considered "incompatible."

[0028] The SP value can also be expressed as three components: dispersion term: energy due to intermolecular dispersion forces (δDD), polar term: energy due to intermolecular dipole interactions (δP), and hydrogen bond term: energy due to intermolecular hydrogen bonds (δH). (SP value) 2 =(δD) 2 +(δP) 2 +(δH) 2 As for the inorganic particles used in the epoxy resin composition of this embodiment, the preferred ranges for each are ΔD of preferably 13 or more, more preferably 14 or more, even more preferably 18 or less, and still more preferably 17 or less. ΔP is preferably 4 or more, more preferably 5 or more, even more preferably 12 or less, and still more preferably 11 or less. ΔH is preferably 9 or more, more preferably 10 or more, even more preferably 20 or less, and still more preferably 19 or less.

[0029] (Inorganic particles) The inorganic particles used in the epoxy resin composition of this embodiment have an SP value of 18 or more and 28 or less. By setting the SP value within this range, compatibility with the epoxy resin is improved, and dispersion of the inorganic particles can be facilitated. From the viewpoint of compatibility with the epoxy resin, the SP value is preferably 19 or more, more preferably 20 or more, even more preferably 21 or more, and still more preferably 22 or more. The SP value is also preferably 27 or less, more preferably 26 or less, and even more preferably 25 or less. Furthermore, by setting the SP value of the inorganic particles within the above range, the inorganic particles are uniformly dispersed in the epoxy resin, and the epoxy resin composition of this embodiment tends to have excellent injectability without clogging. This is because setting the SP value of the inorganic particles to 18 or more makes it possible to keep the difference in SP value between the epoxy resin and the inorganic particles small, and setting it to 28 or less makes it possible to prevent water contamination and deterioration of the epoxy groups. The SP value of inorganic particles can be controlled within the above-mentioned range by treating the surfaces of the inorganic particles with any surface treatment agent. The SP value of inorganic particles can be determined using the Hansen dissolved sphere method as described above, and specifically, can be measured by the method described in the Examples below.

[0030] The type of inorganic particles is not limited to the following, but examples thereof include silica, alumina, silicon nitride, mica, and white carbon. From the viewpoint of suppressing the thermal expansion coefficient when the epoxy resin composition of the present embodiment is used as a material for an interlayer adhesive, silica and alumina are preferred. From the viewpoint of high dispersibility in the epoxy resin composition, silica is more preferred.

[0031] The inorganic particles have an average particle size of preferably 10 μm or less, more preferably 8 μm or less, even more preferably 5 μm or less, even more preferably 3 μm or less, and still more preferably 1 μm or less, from the viewpoint of permeability when the epoxy resin composition of this embodiment is used as a sealant. Also, from the viewpoint of preventing an increase in viscosity of the epoxy resin composition of this embodiment, the average particle size is preferably 0.01 μm or more, more preferably 0.05 μm or more, even more preferably 0.1 μm or more, and even more preferably 0.2 μm or more. The average particle size of the inorganic particles can be measured by the method described in the Examples below, and can be controlled to fall within the above-mentioned range by controlling the particle size of the inorganic particles that will become the base material before surface treatment.

[0032] The specific surface area of ​​the inorganic particles is 24 m from the viewpoint of preventing an increase in the viscosity of the epoxy composition of the present embodiment. 2 / g or less is preferable, and 15m 2 / g or less, more preferably 13m 2 / g or less, and even more preferably 12m 2 / g or less, even more preferably 10m 2 / g or less. 2 / g or more is preferable, and 3m 2 / g or more, more preferably 4m 2 / g or more, more preferably 5m 2 / g or more. The specific surface area of ​​the inorganic particles can be measured by the BET method, which measures the amount of gas physically adsorbed on the particle surface when the particles are cooled to a low temperature. The specific surface area can be controlled to fall within the above-mentioned range by controlling the synthesis method of the inorganic particles, the particle size of the inorganic particles, and the surface treatment method.

[0033] The particle size distribution of the inorganic particles is not particularly limited, but from the viewpoint of the permeability of the epoxy resin composition of this embodiment into narrow gaps, the upper limit of the particle size is preferably 50 μm or less, more preferably 45 μm or less, more preferably 40 μm or less, and even more preferably 35 μm or less.

[0034] The shape of the inorganic particles is not particularly limited, and examples thereof include spherical, scaly, fibrous, amorphous, etc. From the viewpoint of the flowability of the epoxy resin composition of the present embodiment, spherical shapes are preferred.

[0035] The inorganic particles are preferably surface-treated with a surface treatment agent represented by the following formula (1) or (2).

[0036] [ka]

[0037] In the formula (1), m is an integer of 3 or more, and A represents one group selected from the group consisting of an epoxy group, an amino group, a mercapto group, a vinyl group, and a ureido group.

[0038] [ka]

[0039] In the formula (2), n is an integer of 8 or more, and A represents one group selected from the group consisting of an epoxy group, an amino group, a mercapto group, a vinyl group, and a ureido group.

[0040] By using a surface treatment agent on the inorganic particles, the flexibility of the epoxy resin composition of this embodiment after curing can be increased, and the fluidity before curing tends to be able to be maintained at a high level.

[0041] The surface treatment agents may be used singly or in combination of two or more. Examples of surface treatment agents include, but are not limited to, epoxy-functional alkoxysilanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; amino-functional alkoxysilanes such as N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane; mercapto-functional alkoxysilanes such as γ-mercaptopropyltrimethoxysilane; and amine-functional alkoxysilanes such as γ-aminopropyltrimethoxysilane and N-2-(aminoethyl)-3-aminopropyltrimethoxysilane.

[0042] The SP value of the surface treatment agent is not particularly limited, but is preferably 7.0 or more and 12.0 or less. By setting it within this range, the SP value of the inorganic particles after surface treatment tends to be in the preferred range. It is more preferably 7.5 or more, even more preferably 8.0 or more, still more preferably 11.0 or less, and even more preferably 10.0 or less.

[0043] The inorganic particles used in the epoxy resin composition of this embodiment preferably have a surface element ratio C / Si of 0.1 or more and 0.7 or less. When the element ratio on the surface of the inorganic particles is within this numerical range, the above-mentioned surface treatment agent tends to cover the surface of the inorganic particles in just the right amount, which increases compatibility with the epoxy resin described below and tends to improve the flow properties of the epoxy resin composition of this embodiment. The surface element ratio C / Si of the inorganic particles is more preferably 0.15 or more, and even more preferably 0.18 or more. It is also more preferably 0.65 or less, and even more preferably 0.63 or less. The surface element ratio C / Si can be controlled within the above range by adjusting the concentration of the surface treatment agent during the surface treatment of the inorganic particles, the concentration of the inorganic particles relative to the solvent during the surface treatment, the surface treatment temperature, and the surface treatment time. As a method for measuring the surface element ratio C / Si of inorganic particles, XPS measurement is performed, and the relative element concentrations of C and Si can be obtained from the area intensities of the C 1s and Si 2p spectra. The measurement conditions of XPS are shown below. <XPS Measurement Conditions> Equipment used: ULVAC-PHI Versa probeII Excitation source: mono.AlKα 20kV × 5mA 100W Analysis size: 100μm × 1.4mm (When acquiring data, mono.AlKα with a diameter of 100μm is oscillated with a width of 1.4mm) Photoelectron extraction angle: 45° Acquisition region Survey scan: 0~1,100eV Narrow scan: C 1s, Si 2p, O 1s Pass Energy Survey scan: 117.4eV Narrow scan: 46.95eV

[0044] The content of the inorganic particles in the epoxy resin composition of this embodiment is preferably 65% by mass or more and 85% by mass or less. In order to ensure good dispersibility, 85% by mass or less is preferable, more preferably 84% by mass or less, still more preferably 83% by mass or less, and even more preferably 80% by mass or less. Also, in order to keep the CTE after curing low, 65% by mass or more is preferable, more preferably 67% by mass or more, and still more preferably 70% by mass or more.

[0045] (Epoxy resin) The epoxy resin composition of this embodiment contains an epoxy resin. The epoxy resin used in the epoxy resin composition of this embodiment preferably includes a p-aminophenol type epoxy resin. By including a p-aminophenol type epoxy resin, the epoxy resin composition of this embodiment tends to be able to keep the viscosity low even when it contains inorganic particles at a high concentration.

[0046] The epoxy resin is not limited to the following, but examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD ​​type epoxy resin, bisphenol M type epoxy resin, bisphenol P type epoxy resin, tetrabromobisphenol A type epoxy resin, biphenyl type epoxy resin, tetramethylbiphenyl type epoxy resin, tetrabromobiphenyl type epoxy resin, diphenyl ether type epoxy resin, benzophenone type epoxy resin, phenylbenzoate type epoxy resin, diphenyl sulfide type epoxy resin, diphenyl sulfoxide type epoxy resin, diphenyl sulfone type epoxy resin, diphenyl disulfide type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, hydroquinone type epoxy resin, methylhydroquinone type epoxy resin, dibutylhydroquinone type epoxy resin, resorcinol type epoxy resin, methylresorcinol type epoxy resin, catechol type epoxy resin, N,N-diglycidylaniline type epoxy resin, ethylene oxide adduct bisphenol A type epoxy resin, propylene oxide adduct bisphenol Examples of epoxy resins include bifunctional epoxy resins such as phenol A-type epoxy resins, ethylene oxide-added bisphenol F-type epoxy resins, p-aminophenol-type epoxy resins, and propylene oxide-added bisphenol F-type epoxy resins; trifunctional epoxy resins such as trisphenol-type epoxy resins, N,N-diglycidylaminobenzene-type epoxy resins, o-(N,N-diglycidylamino)toluene-type epoxy resins, triazine-type epoxy resins, ethylene oxide-added trisphenol-type epoxy resins, and propylene oxide-added trisphenol-type epoxy resins; tetrafunctional epoxy resins such as tetraglycidyldiaminodiphenylmethane-type epoxy resins and diaminobenzene-type epoxy resins; multifunctional epoxy resins such as pentaerythritol-type epoxy resins, phenol novolac-type epoxy resins, cresol novolac-type epoxy resins, triphenylmethane-type epoxy resins, tetraphenylethane-type epoxy resins, dicyclopentadiene-type epoxy resins, naphthol aralkyl-type epoxy resins, and brominated phenol novolac-type epoxy resins; and alicyclic epoxy resins. The liquid epoxy resin preferably has a viscosity of, for example, 0.0001 to 10 Pa·s as measured with an E-type viscometer at room temperature. The epoxy resins may be used alone or in combination of two or more.

[0047] The content of the epoxy resin in the epoxy resin composition of the present embodiment is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more, from the viewpoint of ensuring good dispersibility of the silica, and is preferably 40% by mass or less, more preferably 35% by mass or less, and even more preferably 30% by mass or less, from the viewpoint of keeping the CTE of the epoxy resin composition low.

[0048] (Aromatic amine compound (A-1), amine adduct (A-2)) The epoxy resin composition of the present embodiment comprises: An aromatic amine compound (A-1) represented by the following formula (4) or the following formula (5), an aromatic amine adduct (A-2) which is a reaction product of the aromatic amine compound (A-1) and a reactive compound having a functional group capable of reacting with the aromatic amine compound (A-1); It is preferred that the compound contains: By containing the aromatic amine compound (A-1) and the aromatic amine adduct (A-2), the epoxy resin composition of the present embodiment tends to have improved flowability before curing and improved flexibility after curing.

[0049] <Aromatic amine compound (A-1)> As described above, the aromatic amine compound (A-1) is represented by the following formula (4) or the following formula (5).

[0050] [ka]

[0051] In the formula (4), Rγ and Rδ each independently represent a monovalent organic group having 1 to 20 carbon atoms or a halogen group, c and d each independently represent an integer of 1 to 4, and Y represents a divalent organic group or a single bond.

[0052] In Rγ and Rδ, the monovalent organic group having 1 to 20 carbon atoms is preferably an organic group having 1 to 10 carbon atoms, more preferably an organic group having 1 to 5 carbon atoms, and even more preferably an organic group having 1 to 3 carbon atoms. c and d are each independently preferably an integer of 0 to 2, and more preferably an integer of 0 or 1. In Y of the formula (4), the divalent organic group may be a divalent organic group that does not have an aromatic ring.

[0053] Examples of the aromatic amine compound represented by formula (4) include, but are not limited to, m-tolidine, 2,2'-bis(trifluoromethyl)benzidine, 4,4'-diamino-3,3'-diethyl-5,5'-dimethyldiphenylmethane, 3,3'-diethyl-4,4'-diaminodiphenylmethane, 4,4'-diamino-3,3'-diethyl-5,5'-dimethyldiphenylmethane, bis(4-amino-3,5-dimethylphenyl)methane, and 4,4'-diamino-3,3'-5,5'-tetraethyldiphenylmethane. These aromatic amine compounds may be used alone or in combination of two or more. Among the above, 3,3'-diethyl-4,4'-diaminodiphenylmethane is more preferred as the aromatic amine compound represented by formula (4) from the viewpoint of achieving both curability and storage stability after mixing with an epoxy resin.

[0054] [ka]

[0055] In the formula (5), Rε represents a monovalent organic group having 1 to 20 carbon atoms or a halogen group, and e represents an integer of 1 to 4.

[0056] Examples of the aromatic amine compound represented by the formula (5) include, but are not limited to, diethyltoluenediamine (2,4-diamino-3,5-diethyltoluene, 2,6-diamino-3,5-diethyltoluene), dimethylthiotoluenediamine, and the like. These aromatic amine compounds may be used alone or in combination of two or more. Among the above, diethyltoluenediamine (2,4-diamino-3,5-diethyltoluene and 2,6-diamino-3,5-diethyltoluene) is preferred as the aromatic amine compound represented by formula (5) from the viewpoint of achieving both curability and storage stability after mixing with an epoxy resin.

[0057] <Aromatic amine adduct (A-2)> The aromatic amine adduct (A-2) is a reaction product between the aromatic amine compound (A-1) and a reactive compound having a functional group capable of reacting with the aromatic amine compound (A-1).

[0058] [Reactive compounds] The reactive compound has a functional group capable of reacting with the aromatic amine compound (A-1). Examples of the functional group include a -C(=O)OC(=O)- group, a carboxyl group, a sulfo group, an isocyanato group, a carbonyl group, an epoxy group, a fluoro group, a chloro group, a bromo group, and an iodo group.

[0059] The reactive compound is preferably at least one compound selected from the group consisting of acid anhydrides, acid dianhydrides, carboxylic acid compounds, sulfonic acid compounds, isocyanate compounds, urea compounds, epoxy compounds, and alkyl halide compounds.

[0060] Examples of the carboxylic acid compound include, but are not limited to, succinic acid, adipic acid, sebacic acid, phthalic acid, and dimer acid.

[0061] The sulfonic acid compound is not limited to the following, but examples thereof include ethanesulfonic acid and p-toluenesulfonic acid.

[0062] Examples of the isocyanate compound include, but are not limited to, aliphatic diisocyanates, alicyclic diisocyanates, aromatic diisocyanates, aliphatic triisocyanates, and polyisocyanates. Examples of the aliphatic diisocyanate include, but are not limited to, ethylene diisocyanate, propylene diisocyanate, butylene diisocyanate, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate. Examples of alicyclic diisocyanates include, but are not limited to, isophorone diisocyanate, 4-4'-dicyclohexylmethane diisocyanate, norbornane diisocyanate, 1,4-isocyanatocyclohexane, 1,3-bis(isocyanatomethyl)-cyclohexane, and 1,3-bis(2-isocyanatopropyl-2-yl)-cyclohexane. Examples of aromatic diisocyanates include, but are not limited to, tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylene diisocyanate, and 1,5-naphthalene diisocyanate. Examples of the aliphatic triisocyanate include, but are not limited to, 1,3,6-triisocyanatomethylhexane, 2,6-diisocyanatohexanoate-2-isocyanatoethyl, and the like. The polyisocyanate is not limited to the following, but examples thereof include polymethylene polyphenyl polyisocyanate and polyisocyanates derived from the above diisocyanate compounds. Examples of polyisocyanates derived from the diisocyanates include, but are not limited to, isocyanurate-type polyisocyanates, biuret-type polyisocyanates, urethane-type polyisocyanates, allophanate-type polyisocyanates, and carbodiimide-type polyisocyanates.

[0063] Examples of urea compounds include, but are not limited to, urea, methyl urea, dimethyl urea, ethyl urea, and t-butyl urea.

[0064] As the epoxy compound, a monoepoxy compound and / or a polyepoxy compound can be used.

[0065] Examples of monoepoxy compounds include, but are not limited to, butyl glycidyl ether, hexyl glycidyl ether, phenyl glycidyl ether, 2-ethylhexyl glycidyl ether, dodecyl glycidyl ether, allyl glycidyl ether, para-tert-butylphenyl glycidyl ether, ethylene oxide, propylene oxide, paraxylyl glycidyl ether, glycidyl acetate, glycidyl butyrate, glycidyl hexoate, and glycidyl benzoate.

[0066] Examples of polyepoxy compounds include, but are not limited to, bisphenol-type epoxy compounds obtained by glycidylating bisphenols such as bisphenol A, bisphenol F, bisphenol AD, bisphenol S, tetramethylbisphenol A, tetramethylbisphenol F, tetramethylbisphenol AD, tetramethylbisphenol S, tetrabromobisphenol A, tetrachlorobisphenol A, and tetrafluorobisphenol A; epoxy compounds obtained by glycidylating dihydric phenols such as biphenol, dihydroxynaphthalene, and 9,9-bis(4-hydroxyphenyl)fluorene; epoxy compounds obtained by glycidylating trisphenols such as 1,1,1-tris(4-hydroxyphenyl)methane and 4,4-(1-(4-(1-(4-hydroxyphenyl)-1-methylethyl)phenyl)ethylidene)bisphenol; and epoxy compounds obtained by glycidylating tetrakisphenols such as 1,1,2,2-tetrakis(4-hydroxyphenyl)ethane. novolac-type epoxy compounds obtained by glycidylating novolacs such as phenol novolac, cresol novolac, bisphenol A novolac, brominated phenol novolac, and brominated bisphenol A novolac; aliphatic ether-type epoxy compounds obtained by glycidylating polyhydric alcohols such as glycerin and polyethylene glycol; ether ester-type epoxy compounds obtained by glycidylating hydroxycarboxylic acids such as p-oxybenzoic acid and β-oxynaphthoic acid; ester-type epoxy compounds obtained by glycidylating polycarboxylic acids such as phthalic acid and terephthalic acid; glycidyl-type epoxy compounds such as epoxy compounds obtained by glycidylating amine compounds such as 4,4-diaminodiphenylmethane and m-aminophenol, and epoxy compounds obtained by glycidylating amine-type epoxy compounds such as triglycidyl isocyanurate; and alicyclic epoxy compounds such as 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexanecarboxylate.

[0067] As the reactive compound, from the viewpoint of excellent curability and storage stability, an epoxy compound is preferred, and an epoxy compound having one glycidyl group in the molecule is more preferred.

[0068] From the viewpoint of achieving both high curability and storage stability, the total chlorine content of the epoxy compound is preferably 400 ppm or less, more preferably 300 ppm or less, even more preferably 200 ppm or less, still more preferably 180 ppm or less, still more preferably 150 ppm or less, particularly preferably 100 ppm or less, even more preferably 80 ppm or less, and most preferably 50 ppm or less. The total chlorine content of an epoxy compound refers to the total amount of organic chlorine and inorganic chlorine contained in the epoxy compound, and is a value based on the mass of the epoxy compound. Of the total chlorine, the chlorine contained in 1,2-chlorohydrin groups is generally called hydrolyzable chlorine, and the amount of hydrolyzable chlorine in the epoxy compound used in the aromatic amine adduct of the epoxy resin composition of this embodiment is preferably 50 ppm or less, more preferably 0.01 to 20 ppm, and even more preferably 0.05 to 10 ppm. If the amount of hydrolyzable chlorine is 50 ppm or less, the epoxy resin composition of this embodiment is advantageous in achieving both high curability and storage stability, and tends to exhibit excellent electrical properties. Examples of methods for reducing the total chlorine content of an epoxy compound used in an amine adduct include a method in which a dechlorination reaction is carried out using a base catalyst in an aprotic solvent, followed by purifying the epoxy compound by washing with water, and a method in which a dechlorination reaction is carried out using a metal amide compound such as a bis(trialkylsilyl)amide metal salt as a catalyst, followed by purifying the epoxy compound by washing with water.

[0069] The aromatic amine adduct (A-2) is a reaction product between the aromatic amine compound (A-1) and a reactive compound having a functional group capable of reacting with the aromatic amine compound (A-1). The aromatic amine adduct (A-2) used in the epoxy resin composition of the present embodiment can be obtained, for example, by reacting 1 to 5 moles of the aromatic amine compound (A-1) with 1 to 5 moles of a reactive compound (e.g., an epoxy compound) at a temperature of 50 to 250°C for 0.1 to 24 hours, if necessary, in the presence of a solvent, and optionally removing the unreacted aromatic amine compound (A-1) and the solvent. The solvent used here is not particularly limited, but examples thereof include hydrocarbons such as benzene, toluene, xylene, cyclohexane, mineral spirits, naphtha, etc.; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.; esters such as ethyl acetate, n-butyl acetate, propylene glycol monomethyl ether acetate, etc.; alcohols such as methanol, isopropanol, n-butanol, butyl cellosolve, butyl carbitol, etc.; water, etc., and these solvents may be used alone or in combination of two or more. In addition, when an aromatic amine compound (A-1) that is liquid at room temperature is used, a solvent is not required. Good too.

[0070] The content of the aromatic amine compound (A-1) in the aromatic amine adduct (A-2) is preferably from 1% by mass to 15% by mass in terms of obtaining good curability. The content of the aromatic amine adduct (A-2) in the epoxy resin composition of the present embodiment is preferably 1% by mass or more and 15% by mass or less, from the viewpoint of obtaining good curability. The content of the aromatic amine compound (A-1) in the epoxy resin composition is preferably 1% by mass or more and 15% by mass or less, from the viewpoint of obtaining good curability.

[0071] (Agglutinate) When the epoxy resin composition of the present embodiment further contains a curing agent described below, the number of aggregates in a 700 μm × 500 μm observation area of ​​a cured product of the epoxy resin composition is preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less. The number of aggregates in the epoxy resin composition of this embodiment can be reduced to 5 or less by controlling the process parameters so as to prevent aggregation of inorganic particles in the processes from synthesis to kneading. Aggregates are generally 2.0 μm or larger in size and are separated from the background when the cured product is observed under the following conditions and data is processed. A test specimen with a surface for microscopic observation can be prepared by mixing the epoxy resin composition with the curing agent in a planetary mixer, applying it to a glass slide with a bar coater, and curing it at 165°C for two hours. The number of aggregates is counted by segmenting the image using the Segment Anything Model (Meta AI). <Microscope observation conditions> Model: KEYENCE VHX-X1 Magnification: 400x Lighting: Coaxial single beam Brightness: 80 <Conditions for counting the number of aggregates> The obtained image is segmented using Segment Anything Model (Meta AI), and the number of masks is counted to measure the number of agglutinations. In the Segment Anything Model, the image embedding and the embedded prompt (2D point or BB) information are input to the mask decoder to generate a segment mask, but by inputting the number of points specified in points_per_batch as prompts for the entire image and generating a mask for the corresponding prompt, it is possible to automatically segment the entire image without providing prompt information. The conditions for use are as follows: points_per_batch=64 pred_iou_thresh=0.6

[0072] (Thickening rate) When the epoxy resin composition of the present embodiment contains a curing agent described below, the viscosity increase rate after standing for 60 minutes at 110° C. is preferably 1.0 to 40.0 times. The viscosity after standing for 60 minutes at 110° C. can be measured using a rheometer (HAAKEMARS, manufactured by Thermoscientific). The viscosity increase ratio is more preferably 1.0 to 30 times, even more preferably 1.0 to 15 times, and even more preferably 1.0 to 5.0 times. When the viscosity increase ratio is within the above range, the epoxy resin composition of the present embodiment tends to have excellent flowability over a wide range. The viscosity increase rate after leaving the composition at 110°C for 60 minutes can be controlled within the above-mentioned range by selecting an appropriate type and combination of curing agents. For example, the use of an aromatic amine curing agent tends to decrease the viscosity increase rate, and when an amine adduct is used, the addition of an epoxy-based reactive diluent to the aromatic amine tends to decrease the viscosity increase rate. The use of a decomposition-type latent curing agent in combination with these also tends to decrease the viscosity increase rate. More specifically, the viscosity can be controlled by using, for example, a combination of an amine compound or an amine adduct containing an aromatic ring, ester group, sulfonyl group, or the like in its structure with an amine imide compound.

[0073] (hardening agent) The epoxy resin composition of the present embodiment may contain a curing agent. The curing agent is not particularly limited, and examples thereof include, but are not limited to, phenol-based curing agents, amine-based curing agents, and acid anhydride-based curing agents. Examples of phenolic curing agents include, but are not limited to, phenol novolac resin, cresol novolac resin, dicyclopentadiene-modified phenol resin, phenol aralkyl resin, naphthol aralkyl resin, and terpene-modified phenol resin. Examples of amines include, but are not limited to, dicyandiamide, diaminodiphenylethane, and guanylurea. Examples of imidazoles include, but are not limited to, 2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, and benzimidazole.

[0074] [Cured product] The cured product of the epoxy resin composition of the present embodiment can be obtained by heat curing the epoxy resin composition. Heat curing conditions may be 80° C. to 180° C. for 1 to 10 hours, and heating methods include methods using a heating oven, clean oven, pressure oven, or the like.

[0075] As described above in (Aggregates), the cured product of this embodiment preferably has 5 or fewer aggregates in an observation area of ​​700 μm × 500 μm, more preferably 4 or fewer, and even more preferably 3 or fewer. The number of aggregates in the cured product of this embodiment can be reduced to 5 or less by controlling the process parameters so as to prevent aggregation of the inorganic particles in the processes from synthesis to kneading.

[0076] [Sealing materials, etc.] The cured product of this embodiment is useful as a material for a sealing material, a filling material, an insulating material, a sealing material, and the like. As a sealing material, it is useful as a solid sealing material, a liquid sealing material, a film sealing material, etc. As a liquid sealing material, it is useful as an underfill material, a potting material, a dam material, etc. As an insulating material, it is useful as an insulating adhesive film, an insulating adhesive paste, a solder resist, etc. The cured product of this embodiment can be suitably used as a sealant, and the sealant is preferably a semiconductor sealant. The sealing material of this embodiment includes the cured product of this embodiment.

[0077] [Semiconductor Package] The semiconductor package of this embodiment includes the sealing material of this embodiment.

[0078] [Method for producing epoxy resin composition] The method for producing the epoxy resin composition of the present embodiment includes the steps of: (a) modifying the surfaces of inorganic particles by mixing the inorganic particles with a surface treatment agent in a first solvent; (b) removing the surface treatment agent free in the first solvent; (c) a step of dispersing the inorganic particles in a second solvent to obtain an inorganic particle dispersion; a step (d) of mixing the inorganic particle dispersion liquid with an epoxy resin to obtain a mixed liquid; (e) placing the mixture under reduced pressure to remove the second solvent; The following steps are carried out in order: In the steps (a) to (e), the inorganic particles are always present together with a solvent and / or an epoxy resin.

[0079] (Step (a)) Step (a) of the method for producing an epoxy resin composition of this embodiment will be described. In step (a), the inorganic particles are mixed with a surface treatment agent in a first solvent to modify the surfaces of the inorganic particles. The first solvent used in step (a) is not particularly limited, but is preferably compatible with both the inorganic particles and the surface treatment agent. Examples of the first solvent include, but are not limited to, ethanol, acetone, water, methanol, propanol, and isopropanol. One type of first solvent may be used alone, or two or more types may be used in combination.

[0080] Step (a) can also be carried out under heating. The heating temperature can be determined as appropriate, but heating at a temperature of 30°C or higher and 100°C or lower for 1 minute to 2 hours allows the surfaces of the inorganic particles to be treated uniformly. The concentration of the surface treatment agent in the first solvent is not particularly limited, but is preferably 10% by mass or less relative to the first solvent to prevent reactions between the surface treatment agents. It is more preferably 8% by mass or less, even more preferably 6% by mass or less, and even more preferably 5% by mass or less. Furthermore, to ensure uniform surface treatment, the concentration is preferably 0.01% by mass or more relative to the solvent, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, and even more preferably 0.5% by mass or more. The concentration of the inorganic particles in the first solvent is not particularly limited, but is preferably 30% by mass or less relative to the first solvent, more preferably 25% by mass or less, even more preferably 20% by mass or less, and even more preferably 15% by mass or less. Furthermore, to ensure uniform surface treatment, the concentration is preferably 0.1% by mass or more relative to the first solvent, more preferably 0.5% by mass or more, even more preferably 0.8% by mass or more, and even more preferably 1.0% by mass or more.

[0081] As the surface treatment agent, those mentioned above are preferably used. The mass ratio of the surface treatment agent to the inorganic particles is not particularly limited, but to prevent reactions between the surface treatment agents, it is preferably 10 parts by mass or less per 100 parts by mass of the inorganic particles. It is more preferably 8 parts by mass or less, even more preferably 6% by mass or less, and even more preferably 5% by mass or less. Furthermore, to ensure uniform surface treatment, it is preferably 0.01 parts by mass or more per 100 parts by mass of the inorganic particles. It is more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, and even more preferably 0.5 parts by mass or more. The content of the inorganic particles in step (a) is preferably 1% by mass or more and 50% by mass or less, and the content of the first solvent is preferably 99% by mass or more and 50% by mass or less.

[0082] In the method for producing an epoxy resin composition according to this embodiment, it is preferable that the SP value of the inorganic particles before and after step (a) differ by 0.1 or more. That is, it is preferable that the SP value of the inorganic particles before and after step (a) change by 0.1 or more. This tends to increase the compatibility of the inorganic particles with the epoxy resin and prevent aggregation of the inorganic particles. The range of change in the SP value is preferably 0.1 or more, more preferably 0.2 or more, and even more preferably 0.3 or more. The SP value of the inorganic particles before surface treatment is not particularly limited, but is preferably 20.0 or more and 28.0 or less from the viewpoint of ease of treatment with a surface treatment agent.

[0083] In step (a), the solubility parameter (SP value) of the inorganic particles after the surface treatment is preferably 18 or more and 28 or less. By controlling the SP value within this range, compatibility with epoxy resins increases, and kneading tends to be possible without aggregation.

[0084] (Step (b)) In step (b) of the method for producing an epoxy resin composition of this embodiment, the surface treatment agent liberated in the first solvent after the surface modification of the inorganic particles is removed. The surface treatment agent can be removed by centrifugal separation, decantation, or filtration. The content of the inorganic particles in step (b) is preferably 30% by mass or more and 98% by mass or less, and the content of the first solvent is preferably 2% by mass or more and 70% by mass or less.

[0085] (Process (c)) In step (c) of the method for producing an epoxy resin composition of this embodiment, the inorganic particles that have been surface-treated as described above are dispersed in a second solvent to obtain a particle dispersion. The second solvent used in step (c) is not limited to, but includes, for example, ethanol, acetone, water, methanol, propanol, and isopropanol. The second solvent may be used alone or in combination of two or more kinds. The boiling point of the second solvent is preferably 110° C. or lower for ease of handling in subsequent steps.

[0086] In step (c), mixing the solvent and inorganic particles does not require high shear force stirring with a torque of 4.5 N m or more; it is preferable to use low shear force stirring with a stirrer, three-one motor, etc. This allows for low energy consumption during the manufacturing process.

[0087] The content of inorganic particles in the inorganic particle dispersion in step (c) is preferably 20% by mass or more and 90% by mass or less, and the content of solvent is preferably 10% by mass or more and 80% by mass or less.

[0088] (Step (d)) In step (d) of the method for producing an epoxy resin composition according to the present embodiment, the inorganic particle dispersion obtained in step (c) is mixed with an epoxy resin to obtain a mixed solution. The mixing method may be, but is not limited to, a stirrer, a three-one motor, a planetary mixer, or the like.

[0089] The epoxy resin used in step (d) preferably contains a p-aminophenol type epoxy resin, which tends to keep the viscosity low even when a high concentration of inorganic particles is contained. The epoxy resins may be used alone or in combination of two or more. Other epoxy resins that can be included include, but are not limited to, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AD ​​type epoxy resins, bisphenol M type epoxy resins, bisphenol P type epoxy resins, tetrabromobisphenol A type epoxy resins, biphenyl type epoxy resins, tetramethylbiphenyl type epoxy resins, tetrabromobiphenyl type epoxy resins, diphenyl ether type epoxy resins, benzophenone type epoxy resins, phenylbenzoate type epoxy resins, diphenyl sulfide type epoxy resins, diphenyl sulfoxide type epoxy resins, diphenyl sulfone type epoxy resins, diphenyl disulfide type epoxy resins, naphthalene type epoxy resins, anthracene type epoxy resins, hydroquinone type epoxy resins, methylhydroquinone type epoxy resins, dibutylhydroquinone type epoxy resins, resorcinol type epoxy resins, methylresorcinol type epoxy resins, catechol type epoxy resins, N,N-diglycidylaniline type epoxy resins, ethylene oxide adduct type bisphenol A type epoxy resins, propylene oxide adduct type epoxy resins. bifunctional epoxy resins such as bisphenol A epoxy resins, ethylene oxide-added bisphenol F epoxy resins, p-aminophenol epoxy resins, and propylene oxide-added bisphenol F epoxy resins; trifunctional epoxy resins such as trisphenol epoxy resins, N,N-diglycidylaminobenzene epoxy resins, o-(N,N-diglycidylamino)toluene epoxy resins, triazine epoxy resins, ethylene oxide-added trisphenol epoxy resins, and propylene oxide-added trisphenol epoxy resins; tetrafunctional epoxy resins such as tetraglycidyldiaminodiphenylmethane epoxy resins and diaminobenzene epoxy resins; multifunctional epoxy resins such as pentaerythritol epoxy resins, phenol novolac epoxy resins, cresol novolac epoxy resins, triphenylmethane epoxy resins, tetraphenylethane epoxy resins, dicyclopentadiene epoxy resins, naphthol aralkyl epoxy resins, and brominated phenol novolac epoxy resins; and alicyclic epoxy resins.

[0090] The content of inorganic particles in the mixed solution in step (d) is preferably 20% by mass or more and 80% by mass or less, the content of solvent is preferably 10% by mass or more and 90% by mass or less, and the content of epoxy resin is preferably 20% by mass or more and 80% by mass or less.

[0091] (Step (e)) In step (e) of the method for producing an epoxy resin composition of this embodiment, the mixed liquid obtained in step (d) is placed under reduced pressure to remove the solvent. The pressure to be reduced is not particularly limited, but it is preferable to adjust it to about 20 hPa or more and 800 hPa or less. The content of inorganic particles in the epoxy resin composition after step (e) is not particularly limited, but to ensure good dispersibility, it is preferably 85% by mass or less, more preferably 84% by mass or less, even more preferably 83% by mass or less, and even more preferably 80% by mass or less. Furthermore, to maintain a low CTE after curing, it is preferably 65% ​​by mass or more, more preferably 67% by mass or more, and even more preferably 70% by mass or more.

[0092] In the step (e) of removing the second solvent, the mixed solution is preferably kept at 150°C or lower. By keeping the temperature within this range, decomposition of the compounds in the mixed solution can be prevented. The mixed solution is more preferably kept at 130°C or lower, even more preferably kept at 110°C or lower, even more preferably kept at 100°C or lower, still more preferably kept at 80°C or lower, and particularly preferably kept at 60°C or lower. The content of the second solvent after step (e) is preferably 5% by mass or less, and the content of the epoxy resin is preferably 15% by mass or more and 35% by mass or less.

[0093] In the method for producing the epoxy resin composition of this embodiment described above, it is preferable to control the surface element ratio C / Si of the inorganic particles to 0.1 or more and 0.7 or less in steps (a) to (c). This tends to ensure that the surface of the inorganic particles is covered with the surface treatment agent in just the right amount, which increases the compatibility between the inorganic particles and the epoxy resin and tends to improve the flowability of the epoxy resin composition of this embodiment. The surface element ratio C / Si of the inorganic particles is more preferably 0.15 or more, and even more preferably 0.18 or more. It is also more preferably 0.65 or less, and even more preferably 0.63 or less. The surface element ratio C / Si can be controlled within the above-mentioned range by adjusting the concentration of the surface treatment agent during the surface treatment of the inorganic particles in step (a), the concentration of the inorganic particles relative to the solvent during the surface treatment, the surface treatment temperature, and the surface treatment time.

[0094] In the method for producing an epoxy resin composition of this embodiment, after the step (e), it is preferable to carry out a step of kneading a curing agent containing the aromatic amine compound (A-1) represented by the formula (4) or the formula (5) and an aromatic amine adduct (A-2) which is a reaction product of the aromatic amine compound (A-1) and a reactive compound having a functional group capable of reacting with the aromatic amine compound (A-1). The amine compound (A-1) and aromatic amine adduct (A-2) are preferably those described above. [Example]

[0095] Hereinafter, the present embodiment will be described with reference to specific examples and comparative examples. However, the present invention is not limited to the following examples and comparative examples, and can be modified as appropriate within the scope of the invention.

[0096] [Methods for measuring physical properties] (Method for measuring the surface element ratio of inorganic particles: C / Si) XPS measurements were carried out on samples of inorganic particles dried on a hot plate at 80 °C for 1 hour or more. From the area intensities of the C 1s and Si 2p spectra, the relative elemental concentrations of C and Si were determined, and the surface element ratio C / Si was calculated. <XPS Measurement Conditions> Equipment used: ULVAC-PHI Versa probeII Excitation source: mono.AlKα 20 kV × 5 mA 100 W Analysis size: 100 μm × 1.4 mm (When data is imported, mono.AlKα with a diameter of 100 μm is oscillated with a width of 1.4 mm) Photoelectron extraction angle: 45° [[ID=I4]]Capture area Survey scan: 0~1,100 eV Narrow scan: C 1s, Si 2p, O 1s Pass Energy Survey scan: 117.4 eV Narrow scan: 46.95 eV

[0097] (SP value of inorganic particles, average particle size of inorganic particles) In five solvents with different SP values, a small amount of inorganic particles was dispersed before and after surface treatment. Two solvents showing values close to the d50 value of the particle size of the inorganic particles were defined as "compatible", and the others were defined as "incompatible". The HSP calculation software HSPiP was used to obtain the results. [[ID=3I]] Note that the measurement sample before surface treatment was prepared by dispersing a small amount of the dried sample in a solvent. The measurement samples after surface treatment used Samples 1 to 6 prepared as described below. In HSPiP, the solvents used were selected from the list of solvent SP values in the software and calculated as the compatible and incompatible solvents classified above. When an error occurred, one of the solvents defined as incompatible was added to the compatible solvents and recalculated. <Measurement Conditions for Particle Size of Inorganic Particles> A sample in which a small amount of inorganic particles were dispersed in a solvent was subjected to dynamic light scattering (DLS) to measure particle size. The d50 calculated by analysis software was used as the average particle size. Equipment: Otsuka Electronics nanoSAQLA Analysis: Cumulant method

[0098] (Method for measuring the number of aggregates) Test pieces for microscopic observation were prepared by dropping 2 mL of the epoxy resin composition onto a 76 × 26 mm glass slide, then applying it to a thickness of 20 μm using a bar coater, and curing it at 165°C for 2 hours to obtain a cured product measuring 30 mm × 20 mm. The side of the test piece on which the epoxy resin composition was applied was used as the observation surface. <Microscope observation conditions> Model: KEYENCE VHX-X1 Magnification: 400x Lighting: Coaxial single beam Brightness: 80 Observation area: 700 μm x 500 μm <Conditions for counting the number of aggregates> The obtained image was segmented using Segment Anything Model (Meta AI), and the number of masks was counted to measure the number of aggregates. In the Segment Anything Model, the image embedding and the embedded prompt (2D point or BB) information are input to the mask decoder to generate a segment mask, but by inputting the number of points specified in points_per_batch as prompts for the entire image and generating a mask for the corresponding prompt, it is possible to automatically segment the entire image without providing prompt information. The conditions for use are as follows: points_per_batch=64 pred_iou_thresh=0.6

[0099] [Method of evaluating characteristics] (Flow evaluation) A test piece was prepared by fixing a glass plate instead of a semiconductor element on a glass substrate (26 mm wide x 75 mm long) with a gap of 25 μm. Next, this test piece was placed on a hot plate set to 110°C, and an epoxy resin composition was applied to one end of the glass plate, and the time (seconds) required for the epoxy resin composition to pass through the gap and reach a point 20 mm away was measured. The obtained time was evaluated according to the following evaluation criteria. <Evaluation criteria> ◎: The arrival time was less than 100 seconds. ○: Arrival time was less than 200 seconds. ×: The arrival time was 200 seconds or more.

[0100] (Method for evaluating the viscosity increase rate) The viscosity increase rate of the epoxy resin composition was evaluated by dropping 0.2 mL of the epoxy resin composition onto a measurement plate. Five and sixty minutes after the sample temperature reached 110°C, the viscosity was measured using a rheometer (HAAKEMARS, manufactured by Thermoscientific) at a constant temperature (110°C) in oscillation mode (f = 1 Hz) (aluminum parallel plate R = 20 mm, 20 ( / sec)). The viscosity after 5 minutes was designated "η1" and the viscosity after 60 minutes was designated "η2." The viscosity increase rate was calculated as η2 / η1. The viscosity increase rate was evaluated according to the following criteria. <Evaluation criteria> A: The viscosity increase rate was 3.0 times or less. B: The viscosity increase rate was more than 3.0 times and 10.0 times or less. C: The viscosity increase rate was more than 10.0 times and 40.0 times or less. D: The viscosity increase rate exceeded 40.0 times.

[0101] [Epoxy resin composition] (Preparation of Sample 1 of Inorganic Particles Used in Examples 1, 7, and 8) 7 g of silica particles (SS-10 manufactured by Tokuyama Corporation, particle size 1.0 μm), 100 g of distilled water, and 0.07 g of a surface treatment agent, a silane coupling agent (KBM403 manufactured by Shin-Etsu Chemical Co., Ltd.), were placed in a flask and reacted for 20 minutes at 30°C while stirring with a magnetic stirrer. The supernatant was then removed by centrifugation. Acetone was added, the mixture was stirred again with a magnetic stirrer, and the supernatant was removed again by centrifugation. This procedure was repeated twice to remove excess silane coupling agent. Acetone was added again and the mixture was stirred with a magnetic stirrer, yielding inorganic particle sample 1. For the inorganic particle sample 1, the sample was dried and then subjected to XPS measurement, and the element ratio C / Si, SP value, and average particle size were calculated.

[0102] (Preparation of Sample 2 of Inorganic Particles Used in Example 2) Sample 2 of inorganic particles was obtained in the same manner as in Example 1, except that the amount of the silane coupling agent was changed to 0.28 g. For the inorganic particle sample 2, the sample was dried and then subjected to XPS measurement, and the element ratio C / Si, SP value, and average particle size were calculated.

[0103] (Preparation of Sample 3 of Inorganic Particles Used in Example 3) Sample 3 of inorganic particles was obtained in the same manner as in Example 1, except that the silica particles used were SS-10 manufactured by Tokuyama Corporation, with a particle size of 1.0 μm. For Sample 3 of inorganic particles, the sample was dried and then subjected to XPS measurement, and the element ratio C / Si, SP value, and average particle size were calculated.

[0104] (Preparation of Sample 4 of Inorganic Particles Used in Examples 4 and 5) Sample 4 was obtained in the same manner as in Example 3, except that the silane coupling agent was KBM402 manufactured by Shin-Etsu Chemical Co., Ltd. For Sample 4 of the inorganic particles, the sample was dried and then subjected to XPS measurement, and the element ratio C / Si, SP value, and average particle size were calculated.

[0105] (Preparation of Sample 5 of Inorganic Particles Used in Example 6) Sample 5 was obtained in the same manner as in Example 3, except that the silane coupling agent was Shin-Etsu Chemical KBM4803.

[0106] (Preparation of Sample 6 of Inorganic Particles Used in Comparative Example 1) 7 g of silica particles (SS-10, manufactured by Tokuyama Corporation, particle size 1.0 μm), 100 g of distilled water, and 0.7 g of silane coupling agent (KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.) were placed in a flask and reacted at 80°C for 60 minutes while stirring with a magnetic stirrer. The supernatant was then removed by centrifugation. Acetone was added, the mixture was stirred again with a magnetic stirrer, and the supernatant was removed by centrifugation. This procedure was repeated twice to remove excess silane coupling agent. The sample was spread on a petri dish and dried at 25°C for 24 hours, followed by drying at 80°C for 2 hours, yielding inorganic particle sample 6. After drying, the sample was subjected to XPS measurement, and the element ratio C / Si, SP value, and average particle size were calculated.

[0107] (Preparation of Curing Agent A Used in Examples 5, 6, and 8) <Synthesis of aromatic amine compounds and aromatic amine adducts> A 500 ml four-neck flask equipped with a reflux condenser and stirring blade was purged with nitrogen, and then 20 g of 1-butanol and 0.05 mol of Ethacure 100 Plus were added and heated until the internal temperature reached 120°C. Then, using a dropping funnel, 0.05 mol of 2-ethylhexyl glycidyl ether (2-EH) was added dropwise over 30 minutes. After the addition was complete, the reaction solution was heated at 120°C for 6 hours while stirring to complete the reaction. Using an evaporator, the 1-butanol was distilled off from the resulting solution over 2 hours, while maintaining the temperature at 80°C and the pressure at 15 mmHg or less, to obtain an epoxy resin curing agent (Curing Agent A). The molar ratios of the aromatic amine (A-1), aromatic amine adduct (A-2-1) in which one molecule of a reactive compound is added to one molecule of the aromatic amine compound (A-1), and aromatic amine adduct (A-2-2X) in which two or more molecules of a reactive compound are added to one molecule of the aromatic amine compound (A-1) contained in the obtained epoxy resin curing agent (curing agent A) were determined by LC / MS measurement and confirmed to be 23:63:14.

[0108] (Preparation of Curing Agent B Used in Example 7) Synthesis and purification were carried out under the same conditions as for curing agent A, except that Ethacure 100 Plus was changed to Kayahard AA, to obtain a curing agent for epoxy resin (curing agent B). The ratio of aromatic amine (B-1), aromatic amine adduct (B-2-1) in which one molecule of a reactive compound is added to one molecule of the aromatic amine compound (B-1), and aromatic amine adduct (B-2-2X) in which two or more molecules of a reactive compound are added to one molecule of the aromatic amine compound (B-1) contained in the obtained epoxy resin curing agent was determined by LC / MS measurement and confirmed to be 11:46:43.

[0109] (Preparation of Epoxy Resin Composition) To 12.0 g of inorganic particle samples 1 to 6 and 9 g of inorganic particle sample 6, 3.0 g of p-aminophenol-type epoxy resin (JER-630LSD, Mitsubishi Chemical) was added, and the mixture was then heated to 45°C under reduced pressure to remove acetone, yielding a mixture. The mixture was stirred in a planetary mixer, and then the curing agent shown in Table 1 below was added. After further stirring in the planetary mixer, the mixture was kneaded using a triple roll mill to yield an epoxy resin composition. The flowability of the epoxy resin composition and the amount of agglomerates in the cured product were measured.

[0110] The compositions, physical properties, and evaluation results of the epoxy resin compositions of Examples 1 to 8 and Comparative Example 1 are shown in Table 1 below. The curing agents and surface treatment agents shown in Table 1 are as follows. <Curing agent> Ethacure 100 Plus (+): A hardener containing diethyltoluenediamine (manufactured by Mitsui Fine Chemicals, Inc.) KAYAHARD AA: A hardener containing 3,3'-diethyl-4,4'-diaminodiphenylmethane (manufactured by Nippon Kayaku Co., Ltd.) <Surface treatment agent> KBM403: 3-glycidoxypropyltrimethoxysilane (silane coupling agent (Shin-Etsu Chemical Co., Ltd.)) KBM402: 3-glycidoxypropylmethyldimethoxysilane (silane coupling agent (Shin-Etsu Chemical Co., Ltd.)) KBM4803: 8-glycidoxyoctyltrimethoxysilane (silane coupling agent (Shin-Etsu Chemical Co., Ltd.))

[0111] [Table 1]

[0112] In all of Examples 1 to 8, the number of agglomerates in the cured product was extremely small or non-existent, and the flowability of the epoxy resin composition was good. In Comparative Example 1, the SP value could not be measured because there was significant interparticle aggregation, making it difficult to redisperse the particles in the solvent. The poor compatibility with the epoxy resin resulted in significant aggregation, resulting in poor flowability. [Industrial Applicability]

[0113] The epoxy resin composition of the present embodiment has industrial applicability in the fields of sealing materials for electric and electronic components such as underfills and relay sealing materials, paste materials such as various insulating liquid adhesives, die attach pastes, conductive pastes and thermally conductive pastes, ink materials such as solder resist inks and hole-filling inks, interlayer insulating materials, film-type solder resists, sealing sheets for semiconductor packages, die attach films, conductive films, anisotropically conductive films, non-conductive films and thermally conductive films.

Claims

1. An epoxy resin composition containing an epoxy resin and inorganic particles, The epoxy resin composition, wherein the inorganic particles have a solubility parameter (SP value) of 18 or more and 28 or less.

2. The epoxy resin includes a p-aminophenol type epoxy resin. The epoxy resin composition according to claim 1.

3. Further containing a curing agent, the number of aggregates in a 700 μm × 500 μm observation surface of the cured product of the epoxy resin composition is 5 or less; The epoxy resin composition according to claim 1.

4. The inorganic particles have a surface element ratio C / Si of 0.1 or more and 0.7 or less. The epoxy resin composition according to claim 1.

5. The inorganic particles have an average particle size of 0.01 μm or more and 10.0 μm or less. The epoxy resin composition according to claim 1.

6. The specific surface area of ​​the inorganic particles is 2 m ２ / g or more 24m ２ / g or less, The epoxy resin composition according to claim 1.

7. The content of the inorganic particles is 65% by mass or more and 85% by mass or less. The epoxy resin composition according to claim 1.

8. 2. The epoxy resin composition according to claim 1, wherein the inorganic particles are surface-treated with a surface treatment agent represented by the following formula (1) or (2): 【Chemical 1】 【Chemistry 2】 In formula (1), m is an integer of 3 or more, and A represents one group selected from the group consisting of an epoxy group, an amino group, a mercapto group, a vinyl group, and a ureido group. In formula (2), n is an integer of 8 or more, and A represents one selected from the group consisting of an epoxy group, an amino group, a mercapto group, a vinyl group, and a ureido group.

9. An aromatic amine compound (A-1) represented by the following formula (4) or the following formula (5), an aromatic amine adduct (A-2) which is a reaction product of the aromatic amine compound (A-1) and a reactive compound having a functional group capable of reacting with the aromatic amine compound (A-1); Further containing The epoxy resin composition according to claim 1. 【Chemistry 3】 (In formula (4), Rγ and Rδ each independently represent a monovalent organic group having 1 to 20 carbon atoms or a halogen group, c and d each independently represent an integer of 1 to 4, and Y represents a divalent organic group or a single bond.) 【Chemistry 4】 (In formula (5), Rε represents a monovalent organic group having 1 to 20 carbon atoms or a halogen group, and e is an integer of 1 to 4.)

10. Further containing a curing agent, The viscosity increase rate after leaving the composition at 110°C for 60 minutes is 1.0 times or more and 40.0 times or less. The epoxy resin composition according to claim 1.

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

12. There are 5 or less aggregates on the 700 μm × 500 μm observation surface. The cured product according to claim 11.

13. A sealing material comprising the cured product according to claim 12.

14. A semiconductor package comprising the encapsulant of claim 13.

15. (a) modifying the surfaces of inorganic particles by mixing inorganic particles with a surface treatment agent in a first solvent; (b) removing the surface treatment agent free in the first solvent; (c) a step of dispersing the inorganic particles in a second solvent to obtain an inorganic particle dispersion; a step (d) of mixing the inorganic particle dispersion liquid with an epoxy resin to obtain a mixed liquid; (e) placing the mixture under reduced pressure to remove the second solvent; The following steps are carried out in order: In the steps (a) to (e), the inorganic particles always coexist with a solvent and / or an epoxy resin. A method for producing an epoxy resin composition.

16. 16. The method for producing an epoxy resin composition according to claim 15, wherein in the steps (a) to (c), the surface element ratio C / Si of the inorganic particles is controlled to be 0.1 or more and 0.7 or less.

17. The epoxy resin includes a p-aminophenol type epoxy resin. A method for producing the epoxy resin composition according to claim 15.

18. In the step (e), The temperature of the mixture is 150°C or less. A method for producing the epoxy resin composition according to claim 15.

19. The inorganic particles have a solubility parameter (SP value) that differs by 0.1 or more before and after the step (a). A method for producing the epoxy resin composition according to claim 15.

20. In the step (c), Do not stir with a high shear force of 4.5 N m or more. A method for producing the epoxy resin composition according to claim 15.

21. After the step (e), an aromatic amine compound (A-1) represented by the following formula (4) or formula (5) is mixed with an aromatic amine adduct (A-2) which is a reaction product of the aromatic amine compound (A-1) and a reactive compound having a functional group capable of reacting with the aromatic amine compound (A-1); A hardener comprising: A method for producing the epoxy resin composition according to claim 15. 【Chemistry 5】 (In formula (4), Rγ and Rδ each independently represent a monovalent organic group having 1 to 20 carbon atoms or a halogen group, c and d each independently represent an integer of 1 to 4, and Y represents a divalent organic group or a single bond.) 【Chemistry 6】 (In formula (5), Rε represents a monovalent organic group having 1 to 20 carbon atoms or a halogen, and e is an integer of 1 to 4.)

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