Epoxy resin composition, electronic component device, and method for manufacturing electronic component device

Abstract

This epoxy resin composition contains an epoxy resin and a curing agent containing a compound represented by general formula (B). In general formula (B), each R1 independently represents a C1-6 alkyl group. n is an integer of 0 to 10.

Description

[Technical Field]

[0001] The present disclosure relates to an epoxy resin composition, an electronic component device, and a method for producing an electronic component device. [Background technology]

[0002] In recent years, semiconductor elements have become increasingly densely packed. Accordingly, surface-mounted packages have become the mainstream for resin-encapsulated semiconductor devices, replacing conventional pin-insertion packages. Surface-mounted ICs (Intergrated Circuits), LSIs (Large Scale Integration), and other devices are being packaged in thin, compact packages to increase packaging density and reduce mounting height. As a result, the area occupied by the elements in the package has increased, and the thickness of the package has become extremely thin.

[0003] Furthermore, these packages differ in their mounting method from conventional pin-insertion packages. Pin-insertion packages are soldered from the backside of the wiring board after the pins are inserted into the board, preventing direct exposure to high temperatures. However, surface-mount ICs are temporarily attached to the surface of the wiring board and then processed using a solder bath or reflow equipment, exposing them directly to soldering (reflow) temperatures. As a result, if the IC package absorbs moisture, the absorbed moisture vaporizes during reflow, generating vapor pressure that acts as peel stress, causing peeling between the insert (e.g., chip, lead frame) and the encapsulant, resulting in package cracks and poor electrical performance. Therefore, there is a need for encapsulating materials with excellent solder heat resistance (reflow resistance).

[0004] As an epoxy resin composition having excellent reflow resistance, an epoxy resin composition containing an epoxy resin including a specific epoxy resin and a curing agent including at least one selected from the group consisting of biphenylene-type phenol aralkyl resins, phenol aralkyl resins, and triphenylmethane-type phenol resins has been proposed (see, for example, Patent Document 1).

[0005] Furthermore, epoxy resin compositions have been widely used in the field of encapsulating electronic components such as transistors and ICs because epoxy resins offer a good balance of electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesive properties with insert parts.

[0006] Transfer molding is the most common method for encapsulating electronic components using epoxy resin compositions. However, in transfer molding, a molten epoxy resin composition is forced to flow within a mold by pressure, which can lead to wire sweep. To address this issue, methods for increasing the fluidity of epoxy resin compositions have been investigated, but there are still challenges in suppressing wire sweep. Compression molding is known as an alternative molding method to transfer molding. In compression molding, an epoxy resin composition is placed in a mold cavity and melted, and the mold is then closed and pressurized to encapsulate the device. Compression molding minimizes the flow of the epoxy resin composition, thereby suppressing wire sweep.

[0007] As an epoxy resin composition for encapsulating semiconductor elements by compression molding, for example, Patent Document 2 proposes a particulate epoxy resin composition containing an epoxy resin, a curing agent, a curing accelerator, an inorganic filler, a fatty acid having a melting point of 70°C or less, and a silane coupling agent having a boiling point of 200°C or more, and characterized in that the particle size distribution is such that 85% by mass or more falls within the range of 100 μm to 3 mm. It is described that the use of such an epoxy resin composition allows it to be sufficiently melted during compression molding, thereby improving filling properties.

[0008] Furthermore, in recent years, the trend toward higher speeds and higher densities in the field of electronic components has led to a significant increase in the amount of heat generated by these components. Demand for electronic components that operate at high temperatures is also increasing. Therefore, there is a demand for improved thermal conductivity in plastics, particularly cured epoxy resins, used to seal electronic components.

[0009] As a method for improving the thermal conductivity of a cured epoxy resin, a method has been reported in which the amount of a highly thermally conductive filler such as alumina filled in an epoxy resin composition is increased (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-74703 [Patent Document 2] Japanese Patent Application Laid-Open No. 2011-153173 [Patent Document 3] Japanese Patent Application Laid-Open No. 2007-153969 Summary of the Invention [Problem to be solved by the invention]

[0011] For example, there is room for improvement in reflow resistance in encapsulating materials that use phenol novolac resin as a curing agent, as in Patent Document 1. A first embodiment of the present disclosure relates to providing an encapsulating epoxy resin composition that has excellent reflow resistance, and an electronic component device that includes elements encapsulated therewith.

[0012] Furthermore, in the epoxy resin composition used in compression molding, the proportion and particle size distribution of the inorganic filler may be adjusted to achieve various properties such as low moisture absorption and high thermal conductivity in the cured product. Furthermore, from the viewpoint of obtaining desired physical properties, such as maintaining low viscosity while achieving high loading by adjusting the proportion and particle size distribution of the inorganic filler, it is desirable for the epoxy resin composition to have a high degree of freedom in design. Therefore, it is desirable to obtain an epoxy resin composition that is easily melted and suitable for device encapsulation by compression molding by a method other than the method described in Patent Document 1. In view of the above circumstances, a second embodiment of the present disclosure relates to providing an easily meltable epoxy resin composition for compression molding, and an electronic component device including an element encapsulated therewith.

[0013] Furthermore, in recent years, there has been an increasing demand for higher thermal conductivity, but with conventional methods, there have been limitations, such as the fact that the epoxy resin composition becomes highly viscous as the amount of highly thermally conductive filler added increases, making it impossible to knead, and so there have been limitations on how much higher thermal conductivity can be achieved. Furthermore, as semiconductor devices become thinner and larger, the stress applied to the cured product of an epoxy resin composition used to encapsulate the semiconductor device tends to increase. Therefore, there is a need for the development of an epoxy resin composition that not only exhibits thermal conductivity but also excellent strength after curing. Here, increasing the content of a highly thermally conductive filler such as alumina tends to increase the bending strength up to a certain level, but once the content exceeds a certain level, the cured product becomes brittle and the bending strength tends to decrease. Thus, it has been difficult to achieve high thermal conductivity while maintaining high bending strength. In view of the above circumstances, a third embodiment of the present disclosure relates to providing an encapsulating epoxy resin composition capable of producing a cured product having excellent thermal conductivity and bending strength, as well as an electronic component device including a cured product of the encapsulating epoxy resin composition and a method for manufacturing the same. [Means for solving the problem]

[0014] Specific means for achieving the above object are as follows. <1> An encapsulating epoxy resin composition comprising an epoxy resin and a curing agent containing a compound represented by the following general formula (B): [ka] (In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10. <2> The content of the compound represented by general formula (B) in the curing agent is 30% by mass to 100% by mass. <1> The encapsulating epoxy resin composition according to claim 1. <3> In the general formula (B), R 1 is a methyl group <1> or <2> The encapsulating epoxy resin composition according to claim 1. <4> Mixed with an inorganic filler having a volume average particle size of 2.0 μm or less <1> ~ <3> 10. The encapsulated epoxy resin composition according to claim 1, wherein the epoxy resin composition is a encapsulated epoxy resin composition. <5> The composition further contains an inorganic filler, and the content of the inorganic filler having a particle size of 2.0 μm or less is 5 mass % or more based on the total amount of the inorganic filler. <1> ~ <3> 10. The encapsulated epoxy resin composition according to claim 1, wherein the epoxy resin composition is a encapsulated epoxy resin composition. <6> An epoxy resin composition for compression molding, comprising an epoxy resin and a curing agent containing a compound represented by the following general formula (B):

[0015] [ka]

[0016] (In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10. <7> The content of the compound represented by the general formula (B) in the curing agent is 30% by mass to 100% by mass. <6> The epoxy resin composition for compression molding according to claim 1. <8> In the general formula (B), R 1 is a methyl group <6> or <7> The epoxy resin composition for compression molding according to claim 1. <9> The epoxy resin composition for compression molding further contains a release agent, and the content of the release agent is more than 0% by mass and 2.0% by mass or less relative to the total mass of the epoxy resin composition for compression molding. <6> ~ <8> 1. The epoxy resin composition for compression molding according to claim 1 . <10> An encapsulating epoxy resin composition comprising an epoxy resin, an inorganic filler containing alumina, and a curing agent containing a compound represented by the following general formula (B):

[0017] [ka]

[0018] (In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10. <11> the content of the compound represented by the general formula (B) relative to the total mass of the curing agent is 30% by mass to 100% by mass; <10> The encapsulating epoxy resin composition according to claim 1. <12> In the general formula (B), R 1 is a methyl group <10> or <11> The encapsulating epoxy resin composition according to claim 1. <13> The content of the inorganic filler is 75% by volume or more based on the total volume of the encapsulating epoxy resin composition. <10> ~ <12> 10. The encapsulated epoxy resin composition according to claim 1, wherein the epoxy resin composition is a encapsulated epoxy resin composition. <14> The content of alumina relative to the total mass of the inorganic filler is 75 mass% or more. <10> ~ <13> 10. The encapsulated epoxy resin composition according to claim 1, wherein the epoxy resin composition is a encapsulated epoxy resin composition. <15> The inorganic filler further contains silica, and the average particle size of the silica is 2.0 μm or less. <10> ~ <14> 10. The encapsulated epoxy resin composition according to claim 1, wherein the epoxy resin composition is a encapsulated epoxy resin composition. <16> An element and a device for sealing the element <1> ~ <15> and an electronic component device comprising a cured product of the epoxy resin composition according to any one of claims 1 to 4. <17> <1> ~ <15> 10. A method for producing an electronic component device, comprising encapsulating an element with the epoxy resin composition according to any one of claims 1 to 9. <18> The encapsulation of the element is performed by compression molding. <17> A method for manufacturing the electronic component device according to claim 1. [Effects of the Invention]

[0019] According to the first embodiment of the present disclosure, it is possible to provide an encapsulating epoxy resin composition having excellent reflow resistance, and an electronic component device including an element encapsulated therewith.

[0020] According to the second embodiment of the present disclosure, it is possible to provide an easily meltable epoxy resin composition for compression molding, and an electronic component device including an element encapsulated therein.

[0021] According to a third embodiment of the present disclosure, there are provided an encapsulating epoxy resin composition capable of producing a cured product having excellent thermal conductivity and bending strength, an electronic component device including a cured product of the encapsulating epoxy resin composition, and a method for producing the same. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, embodiments for carrying out the present invention will be described in detail. However, the present invention 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 invention. In the present disclosure, the term "process" includes not only a process that is independent of other processes, but also a process 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 the numerical ranges described in stages in this disclosure, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, in the numerical ranges described in this 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 substances corresponding to the component. 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, the composition may contain multiple types of particles corresponding to each component. 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.

[0023] The first, second and third embodiments will be described in detail below.

[0024] (1) First embodiment <Sealing epoxy resin composition> The encapsulated epoxy resin composition according to the first embodiment contains an epoxy resin and a curing agent including a compound represented by the following general formula (B) (hereinafter also referred to as a "specific curing agent").

[0025] [ka]

[0026] In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10. The encapsulating epoxy resin composition according to the first embodiment has excellent reflow resistance because it contains a specific curing agent.

[0027] Components that can be contained in the encapsulating epoxy resin composition according to the first embodiment will be described in detail below.

[0028] [Epoxy resin] The encapsulating epoxy resin composition according to the first embodiment contains an epoxy resin. The type of epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule. Specifically, the novolac type epoxy resins include novolac type epoxy resins (phenol novolac type epoxy resins, orthocresol novolac type epoxy resins, etc.) obtained by epoxidizing novolac resins obtained by condensing or co-condensing, under an acid 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 type epoxy resins obtained by epoxidizing triphenylmethane type phenolic resins obtained by condensing or co-condensing, under an acid catalyst, the above phenolic compound with an aromatic aldehyde compound such as benzaldehyde, salicylaldehyde, etc.; and novolac type epoxy resins obtained by co-condensing, under an acid catalyst, the above phenolic compound and naphthol compound with an aldehyde compound, Copolymerized epoxy resins, which are diglycidyl ethers of bisphenol A, bisphenol F, etc.; diphenylmethane-type epoxy resins, which are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; stilbene-type epoxy resins, which are diglycidyl ethers of stilbene-based phenolic compounds; sulfur-containing epoxy resins, which are diglycidyl ethers of bisphenol S, etc.; 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 the active hydrogen bonded to the nitrogen atom of aniline, diaminodiphenylmethane, isocyanuric acid, etc. is substituted with a glycidyl group; and dicyclopentadiene-type epoxy resins, which are epoxidized co-condensation resins of dicyclopentadiene and phenolic compounds.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 produced by epoxidizing the olefin bonds 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 phenolic resins, which are glycidyl ethers of dicyclopentadiene-modified phenolic resins. Examples of suitable epoxy resins include pentadiene-modified epoxy resins, cyclopentadiene-modified epoxy resins, which are glycidyl ethers of cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified epoxy resins, which are glycidyl ethers of polycyclic aromatic ring-modified phenolic resins; naphthalene-type epoxy resins, which are glycidyl ethers of naphthalene ring-containing phenolic resins; halogenated phenol novolac-type epoxy resins; hydroquinone-type epoxy resins; trimethylolpropane-type epoxy resins; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; and aralkyl-type epoxy resins obtained by epoxidizing aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins. Further examples of suitable epoxy resins include epoxidized silicone resins and epoxidized acrylic resins. These epoxy resins may be used alone or in combination of two or more.

[0029] Among the above epoxy resins, from the viewpoint of a balance between reflow resistance and fluidity, epoxy resins selected from the group consisting of biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, sulfur-atom-containing epoxy resins, novolac-type epoxy resins, dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, copolymer-type epoxy resins, and aralkyl-type epoxy resins (these are referred to as "specific epoxy resins"). The specific epoxy resins may be used alone or in combination of two or more.

[0030] When the epoxy resin contains a specific epoxy resin, the total content of the specific epoxy resin is preferably 30% by mass or more, and more preferably 50% by mass or more, of the total epoxy resin, from the viewpoint of exhibiting the performance of the specific epoxy resin.

[0031] Among the specific epoxy resins, from the viewpoint of fluidity, biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, and sulfur-atom-containing epoxy resins are more preferred, and from the viewpoint of heat resistance, dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, and aralkyl-type epoxy resins are preferred.

[0032] Among these, from the viewpoint of further enhancing fluidity, the epoxy resin preferably contains a biphenyl-type epoxy resin. When the epoxy resin contains a biphenyl-type epoxy resin, the content of the biphenyl-type epoxy resin is preferably 30% by mass to 100% by mass, more preferably 50% by mass to 100% by mass, and even more preferably 70% by mass to 100% by mass, based on the total mass of the epoxy resin. Specific examples of preferred epoxy resins are shown below.

[0033] The biphenyl type epoxy resin is not particularly limited as long as it is an epoxy resin having a biphenyl skeleton. For example, an epoxy resin represented by the following general formula (II) is preferred. Among the epoxy resins represented by the following general formula (II), R 8 When the oxygen atom is substituted at the 4 and 4' positions, the 3, 3', 5, and 5' positions are methyl groups, and the other R 8 YX-4000H (Mitsubishi Chemical Corporation, product name) where R is a hydrogen atom, 8 4,4'-bis(2,3-epoxypropoxy)biphenyl, where R is a hydrogen atom, 8 When is a hydrogen atom and R 8 When the oxygen atom is substituted at the 4 and 4' positions, the 3, 3', 5, and 5' positions are methyl groups, and the other R 8is a hydrogen atom, YL-6121H (trade name, Mitsubishi Chemical Corporation) and the like are commercially available.

[0034] [ka]

[0035] In formula (II), R 8 represents a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, or an aromatic group having 4 to 18 carbon atoms, and may all be the same or different. n is an average value and represents a number of 0 to 10.

[0036] The stilbene type epoxy resin is not particularly limited as long as it is an epoxy resin having a stilbene skeleton. For example, an epoxy resin represented by the following general formula (III) is preferred. Among the epoxy resins represented by the following general formula (III), R 9 When the oxygen atom is substituted at the 4 and 4' positions, the 3, 3', 5, and 5' positions are methyl groups, and the other R 9 is a hydrogen atom, and R 10 are all hydrogen atoms, and R 9 Three of the 3, 3', 5, and 5' positions are methyl groups, one is a t-butyl group, and the remaining R 9 is a hydrogen atom, and R 10 A mixture of 1 and 2 in which all of the above are hydrogen atoms is commercially available as ESLV-210 (product name, Sumitomo Chemical Co., Ltd.).

[0037] [ka]

[0038] In formula (III), R 9 and R 10 represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and may be the same or different from each other. n is an average value and represents a number of 0 to 10.

[0039] The diphenylmethane type epoxy resin is not particularly limited as long as it is an epoxy resin having a diphenylmethane skeleton. For example, an epoxy resin represented by the following general formula (IV) is preferred. Among the epoxy resins represented by the following general formula (IV), R 11 are all hydrogen atoms, and R 12 When the oxygen atom is substituted at the 4 and 4' positions, the 3, 3', 5, and 5' positions are methyl groups, and the other R 12 YSLV-80XY (Nippon Steel Chemical & Material Co., Ltd., product name) in which is a hydrogen atom is commercially available.

[0040] [ka]

[0041] In formula (IV), R 11 and R 12 represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and may be the same or different from each other. n is an average value and represents a number of 0 to 10.

[0042] The sulfur atom-containing epoxy resin is not particularly limited as long as it is an epoxy resin containing a sulfur atom. For example, an epoxy resin represented by the following general formula (V) can be mentioned. Among the epoxy resins represented by the following general formula (V), R 13 When the oxygen atom is substituted at the 4 and 4' positions, the 3 and 3' positions are t-butyl groups, and the 6 and 6' positions are methyl groups. 13 YSLV-120TE (Nippon Steel Chemical & Material Co., Ltd., product name) in which is a hydrogen atom is commercially available.

[0043] [ka]

[0044] In formula (V), R 13represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and may be the same or different from each other. n is an average value and represents a number of 0 to 10.

[0045] The novolac epoxy resin is not particularly limited as long as it is an epoxy resin obtained by epoxidizing a novolac phenolic resin. For example, epoxy resins obtained by epoxidizing a novolac phenolic resin such as a phenol novolac resin, a cresol novolac resin, or a naphthol novolac resin using a method such as glycidyl etherification are preferred, and epoxy resins represented by the following general formula (VI) are more preferred. Among the epoxy resins represented by the following general formula (VI), R 14 are all hydrogen atoms, and R 15 is a methyl group, and i=1; ESCN-190, ESCN-195 (product names of Sumitomo Chemical Co., Ltd.); 14 are all hydrogen atoms and i=0, N-770 and N-775 (trade names, DIC Corporation), R 14 are all hydrogen atoms, and the part where i=0 and the part where i=1 are R 15 and a moiety that is —CH(CH 3 )—Ph, such as YDAN-1000-10C (trade name, Nippon Steel Chemical & Material Co., Ltd.).

[0046] [ka]

[0047] In formula (VI), R 14 R represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and may be the same or different. 15 represents a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i independently represents an integer of 0 to 3. n is an average value and represents a number of 0 to 10.

[0048] The dicyclopentadiene-type epoxy resin is not particularly limited as long as it is an epoxy resin obtained by epoxidizing a compound having a dicyclopentadiene skeleton as a raw material. For example, an epoxy resin represented by the following general formula (VII) is preferred. Among the epoxy resins represented by the following general formula (VII), HP-7200 (trade name, DIC Corporation), in which i = 0, is commercially available.

[0049] [ka]

[0050] In formula (VII), R 16 represents a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i independently represents an integer of 0 to 3. n is an average value and represents a number of 0 to 10.

[0051] The triphenylmethane epoxy resin is not particularly limited as long as it is an epoxy resin made from a compound having a triphenylmethane skeleton. For example, an epoxy resin obtained by glycidyl etherifying a triphenylmethane phenolic resin, such as a novolac phenolic resin made from a compound having a triphenylmethane skeleton and a compound having a phenolic hydroxyl group, is preferred, and an epoxy resin represented by the following general formula (VIII) is more preferred. Among the epoxy resins represented by the following general formula (VIII), 1032H60 (Mitsubishi Chemical Corporation, trade name) and EPPN-502H (Nippon Kayaku Co., Ltd., trade name), in which i is 0 and k is 0, are commercially available.

[0052] [ka]

[0053] In formula (VIII), R 17 and R 18 represents a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i independently represents an integer of 0 to 3, and each k independently represents an integer of 0 to 4. n is an average value and represents a number of 0 to 10.

[0054] The copolymerized epoxy resin obtained by epoxidizing a novolac resin obtained from a naphthol compound, a phenol compound, and an aldehyde compound is not particularly limited as long as it is an epoxy resin made from a compound having a naphthol skeleton and a compound having a phenol skeleton as raw materials. For example, an epoxy resin obtained by glycidyl etherifying a novolac phenolic resin using a compound having a naphthol skeleton and a compound having a phenol skeleton is preferred, and an epoxy resin represented by the following general formula (IX) is more preferred. Among the epoxy resins represented by the following general formula (IX), R 21 is a methyl group, i is 1, j is 0, and k is 0, and NC-7300 (trade name, Nippon Kayaku Co., Ltd.) is available as a commercially available product.

[0055] [ka]

[0056] In formula (IX), R 19 ~R 21 represents a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i independently represents an integer of 0 to 3, each j independently represents an integer of 0 to 2, and each k independently represents an integer of 0 to 4. Each l and m is an average value and a number of 0 to 10, and (l+m) represents a number of 0 to 10. The terminal of the epoxy resin represented by formula (IX) is either formula (IX-1) or (IX-2) below. In formulas (IX-1) and (IX-2), R 19 ~R 21 The definitions of i, j and k are R in formula (IX). 19 ~R 21 has the same definition as i, j, and k. n is 1 (when bonding via a methylene group) or 0 (when bonding not via a methylene group).

[0057] [ka]

[0058] Examples of the epoxy resin represented by the general formula (IX) include random copolymers containing l structural units and m structural units randomly, alternating copolymers containing them alternately, copolymers containing them regularly, block copolymers containing them in block form, etc. Any of these may be used alone or in combination of two or more.

[0059] Another preferred copolymer epoxy resin is Epiclon HP-5000 (trade name, DIC Corporation), a methoxynaphthalene-cresol-formaldehyde co-condensation epoxy resin containing the following two structural units in a random, alternating, or block order, and represented by the following general formula: In the following general formula, n and m each represent an average value and are numbers from 1 to 10, and (n+m) represents a number from 2 to 10, preferably n and m each represent an average value and are numbers from 1 to 9, and (n+m) represents a number from 2 to 10.

[0060] [ka]

[0061] The aralkyl epoxy resin is not particularly limited as long as it is an epoxy resin made from a phenolic resin synthesized from at least one selected from the group consisting of phenolic compounds such as phenol and cresol and naphthol compounds such as naphthol and dimethylnaphthol, and dimethoxyparaxylene, bis(methoxymethyl)biphenyl, or a derivative thereof. For example, an epoxy resin obtained by glycidyl etherifying a phenolic resin synthesized from at least one selected from the group consisting of phenolic compounds such as phenol and cresol and naphthol compounds such as naphthol and dimethylnaphthol, and dimethoxyparaxylene, bis(methoxymethyl)biphenyl, or a derivative thereof is preferred, and epoxy resins represented by the following general formulas (X) and (XI) are more preferred.

[0062] Among the epoxy resins represented by the following general formula (X), those in which i is 0 and R 38is a hydrogen atom, i is 0, and R 38 is a hydrogen atom and all R 8 CER-3000 (trade name, Nippon Kayaku Co., Ltd.), which is a mixture of an epoxy resin in which i is a hydrogen atom and an epoxy resin in which k is a hydrogen atom at a mass ratio of 80:20, is commercially available. Furthermore, among the epoxy resins represented by the following general formula (XI), ESN-175 (trade name, Nippon Steel Chemical & Material Co., Ltd.), in which i is 0, j is 0, and k is 0, is commercially available.

[0063] [ka]

[0064] In formulas (X) and (XI), R 38 R represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and may be the same or different. 37 , R 39 ~R 41 represents a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i is independently an integer of 0 to 3, each j is independently an integer of 0 to 2, each k is independently an integer of 0 to 4, and each l is independently an integer of 0 to 6. Each n is an average value and is independently a number of 0 to 10.

[0065] R in the above general formulas (II) to (XI) 8 ~R 21 and R 37 ~R 41 In the formula (II), "all of them may be the same or different" means, for example, that 8 to 88 R 8 This means that all of the R may be the same or different. 9 ~R 21 and R 37 ~R 41 In addition, the numbers of R may all be the same or different. 8 ~R 21 and R37 ~R 41 may be the same or different. For example, R 9 and R 10 may all be the same or different. Furthermore, the monovalent organic group having 1 to 18 carbon atoms in the general formulae (III) to (XI) is preferably an alkyl group or an aryl group.

[0066] In the general formulas (II) to (XI), n is an average value, and each independently is preferably in the range of 0 to 10. When n is 10 or less, the melt viscosity of the resin component does not become too high, and the viscosity of the epoxy resin composition during melt molding tends to decrease, and the occurrence of filling defects, deformation of bonding wires (gold wires connecting elements to leads), etc. is more preferably set in the range of 0 to 4.

[0067] The epoxy equivalent 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 functional group 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.

[0068] When the epoxy resin is solid, its softening point or melting point is not particularly limited. From the viewpoints of moldability and reflow resistance, it is preferably 40°C to 180°C, and from the viewpoint of handleability during preparation of the epoxy resin composition, it is more preferably 50°C to 130°C. The melting point of the epoxy resin is a value measured by differential scanning calorimetry (DSC), and the softening point of the epoxy resin is a value measured by a method (ring and ball method) in accordance with JIS K 7234:1986.

[0069] The content of the epoxy resin in the epoxy resin composition is preferably 0.5% by mass to 50% by mass, more preferably 2% by mass to 30% by mass, from the viewpoints of strength, fluidity, heat resistance, moldability, etc.

[0070] [Hardening agent] The encapsulated epoxy resin composition according to the first embodiment contains a curing agent containing a compound (specific curing agent) represented by the following general formula (B).

[0071] [ka]

[0072] In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an isopropyl group, an isobutyl group, a t-butyl group, etc. Of these, a methyl group is preferred.

[0073] The hydroxyl equivalent of the specific curing agent is preferably 100 g / eq to 130 g / eq. The hydroxyl equivalent of the specific curing agent is measured by the method described below.

[0074] When the specific curing agent is solid, its softening point or melting point is not particularly limited, and from the viewpoints of moldability and reflow resistance, it is preferably 40°C to 180°C, and from the viewpoint of handleability during production of the epoxy resin composition, it is more preferably 50°C to 130°C. From the viewpoints of improving flowability and reducing the high-temperature elastic modulus of the cured product of the epoxy resin composition and improving reflow resistance, it is preferably 50°C to 100°C, more preferably 50°C to 75°C, and even more preferably 50°C to 70°C.

[0075] The specific curing agents may be used alone or in combination of two or more. The content of the specific curing agent in the curing agent is preferably 30% by mass to 100% by mass, more preferably 50% by mass to 100% by mass, and even more preferably 70% by mass to 100% by mass.

[0076] Other curing agents include those having a phenolic hydroxyl group in the molecule (phenol curing agents) other than the compound represented by general formula (B).

[0077] Examples of phenolic curing agents other than the compounds represented by general formula (B) include phenolic resins and polyhydric phenolic compounds having two or more phenolic hydroxyl groups per molecule. Specific examples include polyhydric phenolic compounds such as resorcinol, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenols; novolak-type phenolic resins (excluding the compounds represented by general formula (B)) obtained by condensing or co-condensing at least one phenolic compound selected from the group consisting of phenolic compounds such as phenol, m-cresol, p-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, propionaldehyde, benzaldehyde, and salicylaldehyde under an acidic catalyst; and phenolic compounds obtained by condensing or co-condensing at least one phenolic compound selected from the group consisting of dimethoxyparaxylene, bis( Examples of suitable phenolic curing agents include aralkyl phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins synthesized from (methoxymethyl)biphenyl, etc.; paraxylylene and / or metaxylylene-modified phenolic resins; melamine-modified phenolic resins; terpene-modified phenolic resins; dicyclopentadiene-type phenolic resins and dicyclopentadiene-type naphthol resins synthesized by copolymerization of the above phenolic compounds with dicyclopentadiene; cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified phenolic resins; biphenyl-type phenolic resins; triphenylmethane-type phenolic resins obtained by condensing or co-condensing the above phenolic compounds with aromatic aldehyde compounds such as benzaldehyde and salicylaldehyde under an acidic catalyst; and phenolic resins obtained by copolymerizing two or more of these. These phenolic curing agents may be used alone or in combination of two or more.

[0078] Among phenolic curing agents other than the compound represented by general formula (B), from the viewpoint of reflow resistance, at least one selected from the group consisting of aralkyl phenolic resins, dicyclopentadiene phenolic resins, triphenylmethane phenolic resins, copolymerized phenolic resins of benzaldehyde phenolic resins and aralkyl phenolic resins, and novolac phenolic resins (excluding the compound represented by general formula (B)) (these are referred to as "specific phenolic curing agents"). The specific phenolic curing agents may be used alone or in combination of two or more.

[0079] When the curing agent contains a specific phenol curing agent, the content of the specific phenol curing agent may be 5% by mass to 75% by mass, 5% by mass to 70% by mass, 10% by mass to 50% by mass, or 15% by mass to 30% by mass of the entire curing agent.

[0080] Examples of aralkyl phenolic resins include phenol aralkyl resins and naphthol aralkyl resins synthesized from a phenolic compound and dimethoxy-para-xylene, bis(methoxymethyl)biphenyl, etc. The aralkyl phenolic resin may be further copolymerized with other phenolic resins. Examples of copolymerized aralkyl phenolic resins include copolymerized phenolic resins of benzaldehyde phenolic resins and aralkyl phenolic resins, copolymerized phenolic resins of salicylaldehyde phenolic resins and aralkyl phenolic resins, and copolymerized phenolic resins of novolac phenolic resins and aralkyl phenolic resins.

[0081] The aralkyl phenolic resin is not particularly limited as long as it is a phenolic resin synthesized from at least one compound selected from the group consisting of phenol compounds and naphthol compounds, and dimethoxy-para-xylene, bis(methoxymethyl)biphenyl, or a derivative thereof. For example, phenolic resins represented by the following general formulas (XII) to (XIV) are preferred. However, the phenol resin represented by the following general formula (XIII) does not include the compound represented by the above general formula (B).

[0082] [ka]

[0083] In formulas (XII) to (XIV), R 23 R represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and may be the same or different. 22 , R 24 , R 25 and R 28 R represents a monovalent organic group having 1 to 18 carbon atoms, and may be the same or different. 26 and R 27 represents a hydroxyl group or a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i is independently an integer of 0 to 3, each j is independently an integer of 0 to 2, each k is independently an integer of 0 to 4, and each p is independently an integer of 0 to 4. Each n is an average value and is independently a number of 0 to 10.

[0084] Among the phenolic resins represented by the general formula (XII), i is 0 and R 23 MEH-7851 (product name, Meiwa Kasei Co., Ltd.), in which all are hydrogen atoms, is commercially available.

[0085] Among the phenolic resins represented by the general formula (XIII) above, XL-225, XLC (Mitsui Chemicals, Inc., trade name), MEH-7800 (Meiwa Chemical Industry Co., Ltd., trade name), etc., in which i is 0 and k is 0, are commercially available.

[0086] Among the phenolic resins represented by the general formula (XIV), SN-170 (trade name, Nippon Steel Chemical & Material Co., Ltd.), in which j is 0, k is 0, and p is 0, and R 27is a hydroxyl group and p is 0, and SN-395 (trade name, Nippon Steel Chemical & Material Co., Ltd.) is available as a commercially available product.

[0087] The dicyclopentadiene-type phenolic resin is not particularly limited as long as it is a phenolic resin obtained from a compound having a dicyclopentadiene skeleton as a raw material. For example, a phenolic resin represented by the following general formula (XV) is preferred. Among the phenolic resins represented by the following general formula (XV), DPP (trade name, Nippon Petrochemical Co., Ltd.), in which i is 0, is commercially available.

[0088] [ka]

[0089] In formula (XV), R 29 represents a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i independently represents an integer of 0 to 3. n is an average value and represents a number of 0 to 10.

[0090] The triphenylmethane type phenolic resin is not particularly limited as long as it is a phenolic resin obtained from a compound having a triphenylmethane skeleton as a raw material. For example, a phenolic resin represented by the following general formula (XVI) is preferred.

[0091] Among the phenolic resins represented by the following general formula (XVI), MEH-7500 (trade name, Meiwa Kasei Co., Ltd.), in which i and k are 0, is commercially available.

[0092] [ka]

[0093] In formula (XVI), R 30 and R 31represents a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i is independently an integer of 0 to 3, and each k is independently an integer of 0 to 4. n is an average value and is a number of 0 to 10.

[0094] The copolymerized phenolic resin of a benzaldehyde type phenolic resin and an aralkyl type phenolic resin is not particularly limited as long as it is a copolymerized phenolic resin of a phenolic resin obtained from a compound having a benzaldehyde skeleton as a raw material and an aralkyl type phenolic resin. For example, a phenolic resin represented by the following general formula (XVII) is preferred.

[0095] Among the phenolic resins represented by the following general formula (XVII), HE-510 (trade name, Air Water Chemical Co., Ltd.), in which i is 0, k is 0, and q is 0, is commercially available.

[0096] [ka]

[0097] In formula (XVII), R 32 ~R 34 represents a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i is independently an integer of 0 to 3, each k is independently an integer of 0 to 4, and each q is independently an integer of 0 to 5. Each l and m is an average value and independently a number of 0 to 11, provided that the sum of l and m is a number of 1 to 11.

[0098] The novolac phenolic resin is not particularly limited as long as it is a phenolic resin obtained by condensing or co-condensing at least one phenolic compound selected from the group consisting of phenol compounds and naphthol compounds with an aldehyde compound in the presence of an acid catalyst. For example, a phenolic resin represented by the following general formula (XVIII) is preferred.

[0099] Among the phenolic resins represented by the following general formula (XVIII), those in which i is 0 and R 35 Tamanol 758, 759 (trade name, Arakawa Chemical Industries, Ltd.), etc., in which all are hydrogen atoms, are commercially available.

[0100] [ka]

[0101] In formula (XVIII), R 35 R represents a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and may be the same or different. 36 represents a monovalent organic group having 1 to 18 carbon atoms, and may all be the same or different. Each i independently represents an integer of 0 to 3. n is an average value and represents a number of 0 to 10.

[0102] R in the above general formulas (XII) to (XVIII) 22 ~R 36 The expression "may be the same or different" means, for example, that i R 22 This means that all of the R may be the same or different from each other. 23 ~R 36 In addition, the numbers of R may be the same or different from each other. 22 ~R 36 may be the same or different. For example, R 22 and R 23 may be the same or different, and R 30 and R 31 may all be the same or different.

[0103] In the above general formulas (XII) to (XVIII), n is preferably in the range of 0 to 10. If it is 10 or less, the melt viscosity of the resin component will not be too high, and the viscosity of the epoxy resin composition during melt molding will also be low, making it less likely that filling defects, deformation of bonding wires (gold wires connecting elements to leads), etc. will occur. The average n in one molecule is preferably set in the range of 0 to 4.

[0104] The functional group equivalent of the curing agent (hydroxyl group equivalent for a curing agent having a phenolic hydroxyl group in the molecule) is not particularly limited, but from the viewpoint of the balance of various properties such as moldability, reflow resistance, and electrical reliability, it is preferably 70 g / eq to 1000 g / eq, and more preferably 80 g / eq to 500 g / eq.

[0105] The functional group equivalent of the curing agent (hydroxyl group equivalent in the case of a curing agent having a phenolic hydroxyl group in the molecule) may be a value measured by a method according to JIS K 0070:1992, for example.

[0106] When the curing agent is solid, its softening point or melting point is not particularly limited. From the viewpoints of moldability and reflow resistance, it is preferably 40°C to 180°C, and from the viewpoint of handleability during production of the epoxy resin composition, it is more preferably 50°C to 130°C. Furthermore, from the viewpoints of lowering the melt viscosity or improving the flowability, and from the viewpoints of lowering the high-temperature elastic modulus of the cured product of the epoxy resin composition and improving the reflow resistance, the softening point or melting point of the curing agent is preferably 50°C to 100°C, more preferably 50°C to 75°C, and even more preferably 50°C to 65°C.

[0107] 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.

[0108] The equivalent ratio of the epoxy resin to the curing agent, i.e., the ratio of the number of functional groups in the curing agent to the number of epoxy groups in the epoxy resin (number of functional groups in the curing agent / number of epoxy 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 0.7 to 1.2.

[0109] [Curing accelerator] The epoxy resin composition may contain a curing accelerator. The type of curing accelerator is not particularly limited and can be selected depending on the type of epoxy resin, the desired properties of the epoxy resin composition, and the like.

[0110] From the viewpoint of curability and fluidity or viscosity, the curing accelerator preferably contains a phosphonium compound. Specific examples of the phosphonium compound include tertiary phosphines such as triphenylphosphine, diphenyl(p-tolyl)phosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, tris(alkylalkoxyphenyl)phosphine, tris(dialkylphenyl)phosphine, tris(trialkylphenyl)phosphine, tris(tetraalkylphenyl)phosphine, tris(dialkoxyphenyl)phosphine, tris(trialkoxyphenyl)phosphine, tris(tetraalkoxyphenyl)phosphine, trialkylphosphine, dialkylarylphosphine, alkyldiarylphosphine, trinaphthylphosphine, and tris(benzyl)phosphine; and maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, and 2,3-dimethoxybenzoquinone. compounds having intramolecular polarization obtained by adding a compound having a π bond, such as quinone compounds such as bis-1,4-benzoquinone, phenyl-1,4-benzoquinone, and anthraquinone, or diazophenylmethane; compounds having intramolecular polarization obtained by adding the above tertiary phosphines or the above phosphine compounds with 4-bromophenol, 3-bromophenol, 2-bromophenol, 4-chlorophenol, 3-chlorophenol, 2-chlorophenol, 4-iodophenol, 3-iodophenol, 2-iodophenol, ... compounds with intramolecular polarization obtained by reacting halogenated phenolic compounds such as 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, and 4-bromo-4'-hydroxybiphenyl, followed by a dehydrohalogenation step;Examples of such tetra-substituted phosphonium compounds include tetra-substituted phosphonium compounds such as tetraphenylphosphonium, tetraphenylborate salts of tetra-substituted phosphonium compounds such as tetraphenylphosphonium tetra-p-tolylborate, and salts of tetra-substituted phosphonium compounds with phenolic compounds; salts of tetra-substituted phosphonium compounds with anions obtained by removing a proton from a phenolic compound; salts of tetra-substituted phosphonium compounds with anions obtained by removing a proton from a carboxylic acid compound; phosphobetaine compounds; and adducts of phosphonium compounds with silane compounds.

[0111] Among the above phosphonium compounds, the compound represented by the following general formula (I-1) (hereinafter also referred to as a specific curing accelerator) is preferred.

[0112] [ka]

[0113] In formula (I-1), R 1 ~R 3 are each independently a hydrocarbon group having 1 to 18 carbon atoms, and R 1 ~R 3 Two or more of R may be bonded to each other to form a cyclic structure; 4 ~R 7 are each independently a hydrogen atom, a hydroxyl group, or a monovalent organic group having 1 to 18 carbon atoms, and R 4 ~R 7 Two or more of these may be bonded to each other to form a cyclic structure.

[0114] R in general formula (I-1) 1 ~R 3 The "hydrocarbon group having 1 to 18 carbon atoms" described above includes an aliphatic hydrocarbon group having 1 to 18 carbon atoms and an aromatic hydrocarbon group having 6 to 18 carbon atoms.

[0115] From the viewpoint of fluidity or viscosity, the aliphatic hydrocarbon group having 1 to 18 carbon atoms preferably has 1 to 8 carbon atoms, more preferably 2 to 6 carbon atoms, and even more preferably 4 to 6 carbon atoms.

[0116] The aliphatic hydrocarbon group having 1 to 18 carbon atoms may be a linear or branched aliphatic hydrocarbon group having 1 to 18 carbon atoms, or an alicyclic hydrocarbon group having 3 to 18 carbon atoms. From the viewpoint of ease of production, a linear or branched aliphatic hydrocarbon group is preferred.

[0117] Specific examples of linear or branched aliphatic hydrocarbon groups having 1 to 18 carbon atoms include alkyl groups such as methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, t-butyl, pentyl, hexyl, octyl, decyl, and dodecyl; allyl; and vinyl. The linear or branched aliphatic hydrocarbon groups may or may not have a substituent. Examples of the substituent include alkoxy groups such as methoxy, ethoxy, butoxy, and t-butoxy; aryl groups such as phenyl and naphthyl; hydroxyl, amino, and halogen atoms. The linear or branched aliphatic hydrocarbon groups may have two or more substituents, and in such cases, the substituents may be the same or different. When the linear or branched aliphatic hydrocarbon group has a substituent, the total number of carbon atoms contained in the aliphatic hydrocarbon group and the substituent is preferably 1 to 18. From the viewpoint of curability, unsubstituted alkyl groups are preferred, unsubstituted alkyl groups having 1 to 8 carbon atoms are more preferred, and n-butyl, isobutyl, n-pentyl, n-hexyl and n-octyl groups are even more preferred.

[0118] Specific examples of alicyclic hydrocarbons having 3 to 18 carbon atoms include cycloalkyl groups such as cyclopentyl, cyclohexyl, and cycloheptyl, and cycloalkenyl groups such as cyclopentenyl and cyclohexenyl. The alicyclic hydrocarbon group may or may not have a substituent. Examples of the substituent include alkyl groups such as methyl, ethyl, butyl, and tert-butyl; alkoxy groups such as methoxy, ethoxy, butoxy, and t-butoxy; aryl groups such as phenyl and naphthyl; hydroxyl groups; amino groups; and halogen atoms. The alicyclic hydrocarbon group may have two or more substituents, and in such cases, the substituents may be the same or different. When the alicyclic hydrocarbon group has a substituent, the total number of carbon atoms contained in the alicyclic hydrocarbon group and the substituent is preferably 3 to 18. When the alicyclic hydrocarbon group has a substituent, the position of the substituent is not particularly limited. From the viewpoint of curability, unsubstituted cycloalkyl groups are preferred, unsubstituted cycloalkyl groups having 4 to 10 carbon atoms are more preferred, and cyclohexyl, cyclopentyl and cycloheptyl groups are even more preferred.

[0119] The aromatic hydrocarbon group having 6 to 18 carbon atoms preferably has 6 to 14 carbon atoms, and more preferably 6 to 10 carbon atoms. The aromatic hydrocarbon group may or may not have a substituent. Examples of the substituent include alkyl groups such as methyl, ethyl, butyl, and t-butyl; alkoxy groups such as methoxy, ethoxy, butoxy, and t-butoxy; aryl groups such as phenyl and naphthyl; hydroxyl groups; amino groups; and halogen atoms. The aromatic hydrocarbon group may have two or more substituents, and in such cases, the substituents may be the same or different. When the aromatic hydrocarbon group has a substituent, the total number of carbon atoms contained in the aromatic hydrocarbon group and the substituent is preferably 6 to 18. When the aromatic hydrocarbon group has a substituent, the position of the substituent is not particularly limited.

[0120] Specific examples of aromatic hydrocarbon groups having 6 to 18 carbon atoms include phenyl, 1-naphthyl, 2-naphthyl, tolyl, dimethylphenyl, ethylphenyl, butylphenyl, t-butylphenyl, methoxyphenyl, ethoxyphenyl, butoxyphenyl, and t-butoxyphenyl groups. The position of the substituent in these aromatic hydrocarbon groups may be any of ortho, meta, and para positions. From the viewpoint of fluidity or viscosity, unsubstituted aryl groups having 6 to 12 carbon atoms or 6 to 12 carbon atoms including substituents are preferred, unsubstituted aryl groups having 6 to 10 carbon atoms or 6 to 10 carbon atoms including substituents are more preferred, and phenyl, p-tolyl, and p-methoxyphenyl groups are even more preferred.

[0121] R in general formula (I-1) 1 ~R 3 The term "R" is written as 1 ~R 3 Two or more of R may be bonded to each other to form a cyclic structure. 1 ~R 3 In this case, two or three of the R 1 ~R 3 Examples of substituents that can form a cyclic structure when bonded to a phosphorus atom include alkylene groups such as ethylene, propylene, butylene, pentylene, and hexylene, alkenylene groups such as ethyleneylene, propylene, and butylene, aralkylene groups such as methylenephenylene, and arylene groups such as phenylene, naphthylene, and anthracenylene. These substituents may be further substituted with an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, a hydroxyl group, a halogen atom, or the like.

[0122] R in the above general formula (I-1) 4 ~R 7Examples of the "monovalent organic group having 1 to 18 carbon atoms" described above include aliphatic hydrocarbon groups, aromatic hydrocarbon groups, aliphatic hydrocarbonoxy groups, aromatic hydrocarbonoxy groups, acyl groups, hydrocarbonoxycarbonyl groups, and acyloxy groups, which have 1 to 18 carbon atoms and may be substituted or unsubstituted.

[0123] Examples of the aliphatic hydrocarbon group and aromatic hydrocarbon group include R 1 ~R 3 Examples of the aliphatic hydrocarbon group and aromatic hydrocarbon group represented by the formula (I) include those mentioned above.

[0124] Examples of the aliphatic hydrocarbon oxy group include aliphatic hydrocarbon oxy groups having a structure in which an oxygen atom is bonded to the above-mentioned aliphatic hydrocarbon group, such as a methoxy group, ethoxy group, propoxy group, isopropoxy group, n-butoxy group, 2-butoxy group, t-butoxy group, cyclopropyloxy group, cyclohexyloxy group, cyclopentyloxy group, allyloxy group, and vinyloxy group, as well as these aliphatic hydrocarbon oxy groups further substituted with an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, a hydroxyl group, a halogen atom, or the like.

[0125] Examples of the aromatic hydrocarbon oxy group include aromatic hydrocarbon oxy groups having a structure in which an oxygen atom is bonded to the above-mentioned aromatic hydrocarbon group, such as a phenoxy group, a methylphenoxy group, an ethylphenoxy group, a methoxyphenoxy group, a butoxyphenoxy group, or a phenoxyphenoxy group, and these aromatic hydrocarbon oxy groups are further substituted with an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, a halogen atom, or the like.

[0126] Examples of the acyl group include aliphatic hydrocarbon carbonyl groups such as formyl, acetyl, ethylcarbonyl, butyryl, cyclohexylcarbonyl, and allylcarbonyl; aromatic hydrocarbon carbonyl groups such as phenylcarbonyl and methylphenylcarbonyl; and these aliphatic hydrocarbon carbonyl groups or aromatic hydrocarbon carbonyl groups which are further substituted with an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, a halogen atom, or the like.

[0127] Examples of the hydrocarbon oxycarbonyl group include aliphatic hydrocarbon oxycarbonyl groups such as a methoxycarbonyl group, an ethoxycarbonyl group, a butoxycarbonyl group, an allyloxycarbonyl group, and a cyclohexyloxycarbonyl group; aromatic hydrocarbon oxycarbonyl groups such as a phenoxycarbonyl group and a methylphenoxycarbonyl group; and these aliphatic hydrocarbon carbonyloxy groups or aromatic hydrocarbon carbonyloxy groups which are further substituted with an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, a halogen atom, or the like.

[0128] Examples of the acyloxy group include aliphatic hydrocarbon carbonyloxy groups such as a methylcarbonyloxy group, an ethylcarbonyloxy group, a butylcarbonyloxy group, an allylcarbonyloxy group, and a cyclohexylcarbonyloxy group; aromatic hydrocarbon carbonyloxy groups such as a phenylcarbonyloxy group and a methylphenylcarbonyloxy group; and these aliphatic hydrocarbon carbonyloxy groups or aromatic hydrocarbon carbonyloxy groups which are further substituted with an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, a halogen atom, or the like.

[0129] R in the above general formula (I-1) 4 ~R 7 The term "2 or more R 4 ~R 7 may be bonded to each other to form a cyclic structure" means that 2 to 4 R 4 ~R 7may be bonded to form a single divalent to tetravalent organic group as a whole. 4 ~R 7 Examples of the substituent include alkylene groups such as ethylene, propylene, butylene, pentylene, and hexylene, alkenylene groups such as ethyleneylene, propylene, and butylene, aralkylene groups such as methylenephenylene, and arylene groups such as phenylene, naphthylene, and anthracenylene, and other substituents capable of forming a cyclic structure, as well as oxy or dioxy groups thereof. These substituents may be further substituted with an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an amino group, a hydroxyl group, a halogen atom, or the like.

[0130] R in the above general formula (I-1) 4 ~R 7 is not particularly limited. For example, it is preferable that each independently be selected from a hydrogen atom, a hydroxyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted alkoxy group, or a substituted or unsubstituted aryloxy group. Among these, from the viewpoint of availability of raw materials, a hydrogen atom, a hydroxyl group, an aryl group unsubstituted or substituted with at least one selected from the group consisting of an alkyl group and an alkoxy group, or a linear or cyclic alkyl group is preferred. Examples of an unsubstituted aryl group or substituted with at least one selected from the group consisting of an alkyl group and an alkoxy group include a phenyl group, a p-tolyl group, a m-tolyl group, an o-tolyl group, and a p-methoxyphenyl group. Examples of linear or cyclic alkyl groups include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a 2-butyl group, a t-butyl group, an octyl group, and a cyclohexyl group. From the viewpoint of curability, R 4 ~R 7 are all hydrogen atoms, or R 4 ~R 7 It is preferred that at least one of the groups is a hydroxyl group and the rest are all hydrogen atoms.

[0131] In the general formula (I-1), R 1 ~R 3two or more of R are alkyl groups having 1 to 18 carbon atoms or cycloalkyl groups having 3 to 18 carbon atoms; 4 ~R 7 are all hydrogen atoms, or at least one is a hydroxyl group and the rest are all hydrogen atoms. 1 ~R 3 are all alkyl groups having 1 to 18 carbon atoms or cycloalkyl groups having 3 to 18 carbon atoms, and R 4 ~R 7 are all hydrogen atoms, or at least one is a hydroxyl group and the rest are all hydrogen atoms.

[0132] From the viewpoint of rapid curing properties, the specific curing accelerator is preferably a compound represented by the following general formula (I-2).

[0133] [ka]

[0134] In formula (I-2), R 1 ~R 3 are each independently a hydrocarbon group having 1 to 18 carbon atoms, and R 1 ~R 3 Two or more of R may be bonded to each other to form a cyclic structure; 4 ~R 6 are each independently a hydrogen atom or a monovalent organic group having 1 to 18 carbon atoms, and R 4 ~R 6 Two or more of these may be bonded to each other to form a cyclic structure.

[0135] R in general formula (I-2) 1 ~R 6 Specific examples of R in general formula (I-1) 1 ~R 6 The specific examples and preferred ranges are the same as those of the above.

[0136] Specific examples of the specific curing accelerator include an addition reaction product of triphenylphosphine and 1,4-benzoquinone, an addition reaction product of tri-n-butylphosphine and 1,4-benzoquinone, an addition reaction product of tricyclohexylphosphine and 1,4-benzoquinone, an addition reaction product of dicyclohexylphenylphosphine and 1,4-benzoquinone, an addition reaction product of cyclohexyldiphenylphosphine and 1,4-benzoquinone, an addition reaction product of triisobutylphosphine and 1,4-benzoquinone, and an addition reaction product of tricyclopentylphosphine and 1,4-benzoquinone.

[0137] The specific curing accelerator can be obtained, for example, as an adduct of a tertiary phosphine compound and a quinone compound. Specific examples of the tertiary phosphine compound include triphenylphosphine, tributylphosphine, dibutylphenylphosphine, butyldiphenylphosphine, ethyldiphenylphosphine, triphenylphosphine, tris(4-methylphenyl)phosphine, tris(4-ethylphenyl)phosphine, tris(4-propylphenyl)phosphine, tris(4-butylphenyl)phosphine, tris(isopropylphenyl)phosphine, tris(t-butylphenyl)phosphine, tris(2,4-dimethylphenyl)phosphine, tris(2,6-dimethylphenyl)phosphine, tris(2,4,6-trimethylphenyl)phosphine, tris(2,6-dimethyl-4-ethoxyphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(4-ethoxyphenyl)phosphine, etc. From the viewpoint of moldability, triphenylphosphine and tributylphosphine are preferred.

[0138] Specific examples of the quinone compound include o-benzoquinone, p-benzoquinone, diphenoquinone, 1,4-naphthoquinone, anthraquinone, etc. From the viewpoints of moisture resistance and storage stability, p-benzoquinone is preferred.

[0139] The epoxy resin composition may contain a curing accelerator other than the phosphonium compound. Specific examples of curing accelerators other than phosphonium compounds include primary phosphines such as ethylphosphine and phenylphosphine, secondary phosphines such as dimethylphosphine and diphenylphosphine, and organic phosphines such as the above-mentioned tertiary phosphines; diazabicycloalkenes such as 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) and 1,8-diazabicyclo[5.4.0]undecene-7 (DBU); 2-methylimidazole, 2-phenylimidazoline; cyclic amidine compounds such as 2-heptadecylimidazole, 2-phenyl-4-methylimidazole, and 2-heptadecylimidazole; derivatives of the above cyclic amidine compounds; phenol novolak salts of the above cyclic amidine compounds or their derivatives; and the above compounds, in combination with maleic anhydride, 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 quinone compounds such as 1,4-dimethoxy-1,4-benzoquinone and phenyl-1,4-benzoquinone, and compounds having intramolecular polarization obtained by adding a compound having a π bond, such as 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; and ammonium salt compounds such as tetra-n-butylammonium acetate, tetra-n-butylammonium phosphate, tetraethylammonium acetate, tetra-n-hexylammonium benzoate, and tetrapropylammonium hydroxide.

[0140] When the epoxy resin composition contains a specific curing accelerator as a curing accelerator, the content of the specific curing accelerator is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more of the total curing accelerator.

[0141] When the epoxy resin composition contains a curing accelerator, the amount thereof is preferably 0.1 to 30 parts by mass, more preferably 1 to 15 parts by mass, per 100 parts by mass of the resin components. When the amount of the curing accelerator is 0.1 part by mass or more per 100 parts by mass of the resin components, 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 components, the curing speed is not too fast, and a good molded product tends to be obtained.

[0142] [Inorganic filler] The epoxy resin composition may contain an inorganic filler. In particular, when the epoxy resin composition is used as a sealing material for a semiconductor package, it is preferable that the epoxy resin composition contains an inorganic filler.

[0143] The type of inorganic filler is not particularly limited. Specific examples 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. Inorganic fillers with flame retardant properties may also be used. Examples of inorganic fillers with flame retardant properties include aluminum hydroxide, magnesium hydroxide, composite metal hydroxides such as magnesium-zinc composite hydroxide, and zinc borate. Among these, fused silica is preferred from the viewpoint of reducing the linear expansion coefficient, and alumina is preferred from the viewpoint of high thermal conductivity. One type of inorganic filler may be used alone, or two or more types may be used in combination. The inorganic filler may be in the form of powder, beads formed by spheroidizing the powder, or fibers.

[0144] The term "combining two or more inorganic fillers" refers to, for example, using two or more inorganic fillers with the same components but different average particle sizes, using two or more inorganic fillers with the same average particle size but different components, and using two or more inorganic fillers with different average particle sizes and types.

[0145] When the epoxy resin composition contains an inorganic filler, its content is not particularly limited. From the viewpoint of fluidity and strength, it is preferably 30 to 90% by volume, more preferably 35 to 88% by volume, and even more preferably 40 to 85% by volume of the entire epoxy resin composition. When the content of the inorganic filler is 30% by volume or more of the entire epoxy resin composition, the properties of the cured product, such as the thermal expansion coefficient, thermal conductivity, and elastic modulus, tend to be further improved. When the content of the inorganic filler is 90% by volume or less of the entire epoxy resin composition, an increase in the viscosity of the epoxy resin composition is suppressed, and the fluidity is further improved, tending to result in better moldability.

[0146] Furthermore, when the epoxy resin composition contains an inorganic filler, the content of the inorganic filler is preferably 80% by mass to 95% by mass of the total epoxy resin composition, more preferably 85% by mass to 94% by mass, and even more preferably 88% by mass to 93% by mass, from the viewpoints of reflow resistance and fluidity. When the content of the inorganic filler is 80% by mass or more of the total epoxy resin composition, reflow resistance tends to be improved. When the content of the inorganic filler is 95% by mass or less of the total epoxy resin composition, fluidity tends to be excellent.

[0147] The average particle diameter of the inorganic filler is not particularly limited. For example, the volume average particle diameter is preferably 0.2 μm to 80 μm, and more preferably 0.5 μm to 70 μm. When the volume average particle diameter is 0.2 μm or more, an increase in viscosity of the resin composition for mold underfill tends to be further suppressed. When the volume average particle diameter is 80 μm or less, the ability to fill narrow gaps tends to be further improved. The volume average particle diameter of the inorganic filler can be measured as the volume average particle diameter (D50) using a laser diffraction scattering particle size distribution analyzer.

[0148] The volume-average particle size of the inorganic filler in an epoxy resin composition or its cured product can be measured by known methods. For example, a sample of the epoxy resin composition or its cured product can be heated to 800°C or higher using an organic solvent, nitric acid, aqua regia, or the like, followed by ashing. The inorganic filler is extracted from the epoxy resin composition or cured product and thoroughly dispersed using an ultrasonic disperser or the like to prepare a dispersion. The volume-average particle size of the inorganic filler can be measured using this dispersion from the volume-based particle size distribution measured using a laser diffraction / scattering particle size distribution analyzer. Alternatively, the cured product can be embedded in a transparent epoxy resin or the like, polished, and the resulting cross-section observed using a scanning electron microscope to obtain the volume-based particle size distribution. Furthermore, the volume-average particle size of the inorganic filler can be measured by continuously observing two-dimensional cross-sections of the cured product using an FIB (focused ion beam SEM) device or the like and performing three-dimensional structural analysis.

[0149] The maximum particle size (also referred to as the cut point) of the inorganic filler is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of the inorganic filler is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

[0150] From the viewpoint of filling narrow gaps and suppressing burrs, the epoxy resin composition is preferably made by mixing an inorganic filler having a volume average particle size of 2.0 μm or less, more preferably 0.1 μm to 2.0 μm, even more preferably 0.2 μm to 1.5 μm, and particularly preferably 0.3 μm to 1.0 μm.

[0151] When the epoxy resin composition is mixed with an inorganic filler having a volume average particle diameter of 2.0 μm or less, it may also be mixed with an inorganic filler having a volume average particle diameter of more than 2.0 μm. In the epoxy resin composition, the mixing ratio of the inorganic filler having a volume average particle diameter of 2.0 μm or less may be 0.1% by mass to 10% by mass, 0.2% by mass to 5% by mass, or 0.3% by mass to 2% by mass, based on the total mass of the inorganic fillers.

[0152] In the epoxy resin composition, from the viewpoint of filling narrow gaps and suppressing burrs, the content of inorganic fillers having a particle size of 2.0 μm or less is preferably 5% by mass or more relative to the total amount of inorganic fillers. The content of inorganic fillers having a particle size of 2.0 μm or less may be 5% by mass to 30% by mass, 6% by mass to 20% by mass, or 7% by mass to 15% by mass relative to the total amount of inorganic fillers.

[0153] Generally, when an epoxy resin composition contains an inorganic filler with a small particle size (such as fine silica), the increase in viscosity and the decrease in fluidity tend to become more pronounced. On the other hand, the epoxy resin composition according to the first embodiment uses a specific curing agent, and therefore tends to be able to suppress the increase in viscosity and the decrease in fluidity even when an inorganic filler with a small particle size is used.

[0154] From the viewpoint of the flowability of the epoxy resin composition, the particle shape of the inorganic filler is preferably spherical rather than angular, and the particle size distribution of the inorganic filler is preferably wide.

[0155] To obtain a cured product with high thermal conductivity, the inorganic filler preferably contains alumina, and more preferably contains alumina as a main component. When the inorganic filler contains alumina, the average particle size of the alumina is not particularly limited. For example, the volume average particle size of the alumina is preferably 0.2 μm to 80 μm, and more preferably 0.5 μm to 70 μm. When the volume average particle size is 0.2 μm or more, an increase in the viscosity of the epoxy resin composition tends to be suppressed. When the volume average particle size is 80 μm or less, the ability to fill narrow gaps tends to be improved.

[0156] The maximum particle size of the alumina is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of the alumina is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

[0157] In a preferred embodiment, alumina having an average particle size of 0.1 μm to 2.0 μm, preferably 0.2 μm to 1.5 μm, more preferably 0.3 μm to 1.0 μm, and alumina having an average particle size of more than 2.0 μm to 75 μm or less, preferably 5.0 μm to 55 μm, more preferably 8.0 μm to 20 μm, may be used in combination. By using two or more types of alumina having different average particle sizes in combination, the packing property tends to be favorable.

[0158] The shape of the alumina is not particularly limited, but from the viewpoint of kneadability of the epoxy resin composition, the alumina particles are preferably spherical.

[0159] When the inorganic filler contains alumina, the alumina content relative to the total mass of the inorganic filler is preferably 90% by mass or more, more preferably 95% by mass or more, and even more preferably 98% by mass or more, from the viewpoint of high thermal conductivity. Furthermore, from the viewpoints of low viscosity and ease of kneading, the alumina content relative to the total mass of the inorganic filler is preferably 99.9% by mass or less, more preferably 99.8% by mass or less, and even more preferably 99.7% by mass or less.

[0160] When the inorganic filler contains alumina, it is preferable that the inorganic filler contains silica in addition to alumina. When the inorganic filler contains silica, the viscosity tends to decrease and the kneadability and flowability tend to be improved, and the use of particularly fine silica tends to suppress the occurrence of burrs when the cured product is formed. In particular, it is preferable that the inorganic filler contains fine silica, for example, silica having an average particle size of 0.01 μm to 2.0 μm, more preferably 0.1 μm to 1.5 μm, and even more preferably 0.2 μm to 1.0 μm. From the viewpoint of reducing the elastic modulus and the linear expansion coefficient, it is preferable that the inorganic filler contains large particle size silica. The large particle size silica is preferably silica having a particle size of more than 2.0 μm and not more than 75 μm, more preferably 5.0 μm to 55 μm, and even more preferably 8.0 μm to 20 μm.

[0161] From the viewpoints of reflow resistance and suppression of viscosity increase, the inorganic filler preferably contains silica, and may contain silica as a main component. When the inorganic filler contains silica, the average particle size of the silica is not particularly limited. For example, the volume average particle size of silica is preferably 0.2 μm to 80 μm, more preferably 0.5 μm to 70 μm. When the volume average particle size is 0.2 μm or more, the increase in viscosity of the epoxy resin composition tends to be suppressed. When the volume average particle size is 80 μm or less, the filling ability into narrow gaps tends to be improved. Furthermore, the inorganic filler preferably contains fine silica, for example, silica having an average particle size of 0.01 μm to 2.0 μm, more preferably 0.1 μm to 1.5 μm, and even more preferably 0.2 μm to 1.0 μm. When the inorganic filler contains fine silica, the filling ability into narrow gaps tends to be improved and the occurrence of burrs when the cured product is obtained tends to be suppressed.

[0162] The maximum particle size of the silica is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of the silica is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

[0163] The shape of the silica is not particularly limited, but from the viewpoint of kneadability of the epoxy resin composition, the silica particle shape is preferably spherical.

[0164] When the inorganic filler contains silica, the content of silica is not particularly limited and may be 70% to 100% by mass, 80% to 100% by mass, or 90% to 100% by mass relative to the total mass of the inorganic filler. When silica is used in combination with alumina, the content of silica may be 0.1% to 10% by mass, 0.2% to 5% by mass, or 0.3% to 2% by mass relative to the total mass of the inorganic filler.

[0165] [Various additives] In addition to the above-mentioned components, the epoxy resin composition may contain various additives such as coupling agents, ion exchangers, mold release agents, flame retardants, colorants, stress relaxation agents, etc. In addition to the additives exemplified below, the epoxy resin composition may also contain various additives known in the art, as needed.

[0166] (coupling agent) When the epoxy resin composition contains an inorganic filler, it may contain a coupling agent to enhance adhesion between the resin component and the inorganic filler. Examples of the coupling agent include known coupling agents such as silane-based compounds such as epoxysilane, mercaptosilane, aminosilane, alkylsilane, ureidosilane, and vinylsilane, titanium-based compounds, aluminum chelate compounds, and aluminum / zirconium-based compounds.

[0167] Examples of silane compounds include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, octenyltrimethoxysilane, glycidoxyoctyltrimethoxysilane, and methacryloxyoctyltrimethoxysilane.

[0168] Examples of titanium compounds include isopropyl triisostearoyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, isopropyl tri(N-aminoethyl-aminoethyl) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl phosphite) titanate, bis(dioctyl pyrophosphate)oxyacetate titanate, bis(dioctyl pyrophosphate)ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl tridodecyl benzenesulfonyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumyl phenyl titanate, and tetraisopropyl bis(dioctyl phosphite) titanate.

[0169] When the epoxy resin composition contains a coupling agent, the amount of the coupling agent is preferably 0.05 to 5 parts by mass, more preferably 0.1 to 2.5 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, the 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, the moldability of the package tends to be further improved.

[0170] (Ion exchanger) The epoxy resin composition may contain an ion exchanger. In particular, when the epoxy resin composition is used as a molding material for sealing, it is preferable to contain an ion exchanger from the viewpoint of improving the moisture resistance and high-temperature storage characteristics of an electronic component device including the element to be sealed. The ion exchanger is not particularly limited, and a conventionally known one can be used. Specifically, hydrotalcite compounds, and hydrous oxides of at least one element selected from the group consisting of magnesium, aluminum, titanium, zirconium, and bismuth can be mentioned. The ion exchanger may be used alone or in combination of two or more. Among them, hydrotalcite represented by the following general formula (A) is preferable.

[0171] <00008,42>Mg (1-X) Al X (OH)2(CO3) X / 2 ·mH2O ……(A) (0 < X ≦ 0.5, m is a positive number)

[0172] When the epoxy resin composition contains an ion exchanger, its content is not particularly limited as long as it is sufficient to capture ions such as halogen ions. For example, it is preferably 0.1 to 30 parts by mass, more preferably 1 to 15 parts by mass, per 100 parts by mass of the resin component.

[0173] (Release agent) The epoxy resin composition may contain a mold release agent from the viewpoint of obtaining good releasability from the mold 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.

[0174] When the epoxy resin composition contains a release agent, the amount thereof is preferably 0.01 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, per 100 parts by mass of the resin component. 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 15 parts by mass or less, better adhesion tends to be obtained.

[0175] (Flame retardant) The epoxy 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.

[0176] When the epoxy 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 300 parts by mass, more preferably 2 to 150 parts by mass, per 100 parts by mass of the resin component.

[0177] (coloring agent) The epoxy resin composition may further 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.

[0178] (Stress reliever) The epoxy resin composition may contain a stress relaxation agent such as silicone oil or silicone rubber particles. The inclusion of a stress relaxation agent can further reduce package warpage and package cracking. Examples of the stress relaxation agent include commonly used known stress relaxation agents (flexibilizers). Specific examples include thermoplastic elastomers such as silicone, styrene, olefin, urethane, polyester, polyether, polyamide, and polybutadiene; 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. The stress relaxation agents may be used alone or in combination of two or more. Silicone-based stress relaxation agents are preferred. Examples of silicone-based stress relaxation agents include those having epoxy groups, those having amino groups, and polyether-modified versions of these.

[0179] [Method for preparing epoxy resin composition] The method for preparing the epoxy resin composition is not particularly limited. A typical method includes thoroughly mixing predetermined amounts of components using a mixer or the like, melt-kneading the mixture using a mixing roll, extruder, or the like, cooling, and pulverizing the mixture. More specifically, a method includes uniformly 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.

[0180] The epoxy resin composition is preferably solid at room temperature and normal pressure (for example, 25°C and atmospheric pressure). When the epoxy resin composition is solid, its shape is not particularly limited, and examples include powder, granules, tablets, etc. When the epoxy resin composition is in tablet form, it is preferable that the dimensions and mass of the tablet be set to suit the molding conditions of the package, from the viewpoint of handleability.

[0181] (2) Second embodiment <Epoxy resin composition for compression molding> The compression molding epoxy resin composition according to the second embodiment (hereinafter also referred to as "epoxy resin composition") contains an epoxy resin and a curing agent including a compound represented by the following general formula (B) (i.e., "specific curing agent").

[0182] [ka]

[0183] In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms. n represents an integer of 0 to 10. The epoxy resin composition according to the second embodiment contains a specific curing agent, and therefore is easily melted and can be suitably used for compression molding. Furthermore, the epoxy resin composition according to the second embodiment contains a specific curing agent, and therefore has excellent reflow resistance.

[0184] Components that can be contained in the epoxy resin composition according to the second embodiment will be described in detail below.

[0185] [Epoxy resin] The epoxy resin composition according to the second embodiment contains an epoxy resin. The type of the epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule. Specifically, the novolac type epoxy resins include novolac type epoxy resins (phenol novolac type epoxy resins, orthocresol novolac type epoxy resins, etc.) obtained by epoxidizing novolac resins obtained by condensing or co-condensing, under an acid 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 type epoxy resins obtained by epoxidizing triphenylmethane type phenolic resins obtained by condensing or co-condensing, under an acid catalyst, the above phenolic compound with an aromatic aldehyde compound such as benzaldehyde, salicylaldehyde, etc.; and novolac type epoxy resins obtained by co-condensing, under an acid catalyst, the above phenolic compound and naphthol compound with an aldehyde compound, Copolymerized epoxy resins, which are diglycidyl ethers of bisphenol A, bisphenol F, etc.; diphenylmethane-type epoxy resins, which are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; stilbene-type epoxy resins, which are diglycidyl ethers of stilbene-based phenolic compounds; sulfur-containing epoxy resins, which are diglycidyl ethers of bisphenol S, etc.; 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 the active hydrogen bonded to the nitrogen atom of aniline, diaminodiphenylmethane, isocyanuric acid, etc. is substituted with a glycidyl group; and dicyclopentadiene-type epoxy resins, which are epoxidized co-condensation resins of dicyclopentadiene and phenolic compounds.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 produced by epoxidizing the olefin bonds 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 phenolic resins, which are glycidyl ethers of dicyclopentadiene-modified phenolic resins. Examples of suitable epoxy resins include pentadiene-modified epoxy resins, cyclopentadiene-modified epoxy resins, which are glycidyl ethers of cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified epoxy resins, which are glycidyl ethers of polycyclic aromatic ring-modified phenolic resins; naphthalene-type epoxy resins, which are glycidyl ethers of naphthalene ring-containing phenolic resins; halogenated phenol novolac-type epoxy resins; hydroquinone-type epoxy resins; trimethylolpropane-type epoxy resins; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; and aralkyl-type epoxy resins obtained by epoxidizing aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins. Further examples of suitable epoxy resins include epoxidized silicone resins and epoxidized acrylic resins. These epoxy resins may be used alone or in combination of two or more.

[0186] Among the above epoxy resins, from the viewpoint of the balance between reflow resistance and viscosity, epoxy resins selected from the group consisting of biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, sulfur-containing epoxy resins, novolac-type epoxy resins, dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, copolymer-type epoxy resins, and aralkyl-type epoxy resins (these are referred to as "specific epoxy resins"). The specific epoxy resins may be used alone or in combination of two or more.

[0187] When the epoxy resin contains a specific epoxy resin, the total content of the specific epoxy resin is preferably 30% by mass or more, and more preferably 50% by mass or more, of the total epoxy resin, from the viewpoint of exhibiting the performance of the specific epoxy resin.

[0188] Among the specific epoxy resins, from the viewpoint of viscosity, biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, and sulfur-atom-containing epoxy resins are more preferred, and from the viewpoint of heat resistance, dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, and aralkyl-type epoxy resins are preferred.

[0189] The details of the preferably used biphenyl type epoxy resin, stilbene type epoxy resin, diphenylmethane type epoxy resin, sulfur atom-containing type epoxy resin, novolac type epoxy resin, dicyclopentadiene type epoxy resin, triphenylmethane type epoxy resin, copolymer type epoxy resin, and aralkyl type epoxy resin are as described in the first embodiment.

[0190] The epoxy equivalent 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 functional group 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.

[0191] When the epoxy resin is solid, its softening point or melting point is not particularly limited. From the viewpoints of moldability and reflow resistance, it is preferably 40°C to 180°C, and from the viewpoint of handleability during preparation of the epoxy resin composition, it is more preferably 50°C to 130°C. The melting point of the epoxy resin is a value measured by differential scanning calorimetry (DSC), and the softening point of the epoxy resin is a value measured by a method (ring and ball method) in accordance with JIS K 7234:1986.

[0192] The content of the epoxy resin in the epoxy resin composition is preferably 0.5 to 50% by mass, more preferably 2 to 30% by mass, from the viewpoints of strength, viscosity, heat resistance, moldability, etc.

[0193] [Hardening agent] The epoxy resin composition according to the second embodiment contains a curing agent containing the compound (specific curing agent) represented by the general formula (B) described above. The curing agent may further contain other curing agents in addition to the specific curing agent. The details of the curing agent are the same as those of the curing agent according to the first embodiment.

[0194] [Curing accelerator] The epoxy resin composition may contain a curing accelerator. The type of the curing accelerator is not particularly limited. The details of the curing accelerator are the same as those of the curing accelerator in the first embodiment.

[0195] [Inorganic filler] The epoxy resin composition according to the second embodiment may contain an inorganic filler. In particular, when the epoxy resin composition is used as a sealing material for a semiconductor package, it is preferable that the epoxy resin composition contains an inorganic filler.

[0196] The type of inorganic filler is not particularly limited. Specific examples 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. Inorganic fillers with flame retardant properties may also be used. Examples of inorganic fillers with flame retardant properties include aluminum hydroxide, magnesium hydroxide, composite metal hydroxides such as magnesium-zinc composite hydroxide, and zinc borate. Among these, fused silica is preferred from the viewpoint of reducing the linear expansion coefficient, and alumina is preferred from the viewpoint of high thermal conductivity. One type of inorganic filler may be used alone, or two or more types may be used in combination. The inorganic filler may be in the form of powder, beads formed by spheroidizing powder, or fibers.

[0197] The term "combining two or more inorganic fillers" refers to, for example, using two or more inorganic fillers with the same components but different average particle sizes, using two or more inorganic fillers with the same average particle size but different components, and using two or more inorganic fillers with different average particle sizes and types.

[0198] When the epoxy resin composition contains an inorganic filler, its content is not particularly limited. From the viewpoint of viscosity and strength, it is preferably 30 to 90% by volume, more preferably 35 to 88% by volume, and even more preferably 40 to 85% by volume of the entire epoxy resin composition. When the content of the inorganic filler is 30% by volume or more of the entire epoxy resin composition, the properties of the cured product, such as the thermal expansion coefficient, thermal conductivity, and elastic modulus, tend to be further improved. When the content of the inorganic filler is 90% by volume or less of the entire epoxy resin composition, an increase in the viscosity of the epoxy resin composition is suppressed, and the viscosity is further improved, tending to improve moldability.

[0199] Furthermore, when the epoxy resin composition contains an inorganic filler, the content of the inorganic filler is preferably 80% by mass to 95% by mass of the entire epoxy resin composition, more preferably 85% by mass to 94% by mass, and even more preferably 88% by mass to 93% by mass, from the viewpoints of reflow resistance and viscosity. When the content of the inorganic filler is 80% by mass or more of the entire epoxy resin composition, reflow resistance tends to be improved. When the content of the inorganic filler is 95% by mass or less of the entire epoxy resin composition, viscosity tends to be excellent.

[0200] The average particle diameter of the inorganic filler is not particularly limited. For example, the volume average particle diameter is preferably 0.2 μm to 80 μm, and more preferably 0.5 μm to 70 μm. When the volume average particle diameter is 0.2 μm or more, an increase in viscosity of the epoxy resin composition tends to be further suppressed. When the volume average particle diameter is 80 μm or less, the ability to fill narrow gaps tends to be further improved. The volume average particle diameter of the inorganic filler can be measured as the volume average particle diameter (D50) using a laser diffraction scattering particle size distribution analyzer.

[0201] The volume-average particle size of the inorganic filler in an epoxy resin composition or its cured product can be measured by known methods. For example, the inorganic filler is extracted from the epoxy resin composition or its cured product using an organic solvent, nitric acid, aqua regia, or the like, and then thoroughly dispersed using an ultrasonic disperser or the like to prepare a dispersion. Using this dispersion, the volume-average particle size of the inorganic filler can be measured from the volume-based particle size distribution measured using a laser diffraction / scattering particle size distribution analyzer. Alternatively, the cured product can be embedded in a transparent epoxy resin or the like, polished, and the resulting cross-section observed using a scanning electron microscope to obtain the volume-based particle size distribution. Furthermore, the volume-average particle size of the inorganic filler can also be measured by continuously observing two-dimensional cross-sections of the cured product using an FIB (focused ion beam SEM) device or the like and performing three-dimensional structural analysis.

[0202] The maximum particle size (also referred to as the cut point) of the inorganic filler is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of the inorganic filler is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

[0203] From the viewpoint of kneadability of the epoxy resin composition, the particle shape of the inorganic filler is preferably spherical rather than angular, and the particle size distribution of the inorganic filler is preferably wide.

[0204] To obtain a cured product with high thermal conductivity, the inorganic filler preferably contains alumina, and more preferably contains alumina as a main component. When the inorganic filler contains alumina, the average particle size of the alumina is not particularly limited. For example, the volume average particle size of the alumina is preferably 0.2 μm to 80 μm, and more preferably 0.5 μm to 70 μm. When the volume average particle size is 0.2 μm or more, an increase in the viscosity of the epoxy resin composition tends to be suppressed. When the volume average particle size is 80 μm or less, the ability to fill narrow gaps tends to be improved.

[0205] The maximum particle size of the alumina is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of the alumina is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

[0206] In a preferred embodiment, alumina having an average particle size of 0.1 μm to 2.0 μm, preferably 0.2 μm to 1.5 μm, more preferably 0.3 μm to 1.0 μm, and alumina having an average particle size of more than 2.0 μm to 75 μm or less, preferably 5.0 μm to 55 μm, more preferably 8.0 μm to 20 μm, may be used in combination. By using two or more types of alumina having different average particle sizes in combination, the packing property tends to be favorable.

[0207] The shape of the alumina is not particularly limited, but from the viewpoint of kneadability of the epoxy resin composition, the alumina particles are preferably spherical.

[0208] When the inorganic filler contains alumina, the alumina content relative to the total mass of the inorganic filler is preferably 90% by mass or more, more preferably 95% by mass or more, and even more preferably 98% by mass or more, from the viewpoint of high thermal conductivity. Furthermore, from the viewpoints of low viscosity and ease of kneading, the alumina content relative to the total mass of the inorganic filler is preferably 99.9% by mass or less, more preferably 99.8% by mass or less, and even more preferably 99.7% by mass or less.

[0209] When the inorganic filler contains alumina, it is preferable that the inorganic filler contains silica in addition to alumina. When the inorganic filler contains silica, the viscosity tends to decrease and the kneadability and flowability tend to be improved, and the use of particularly fine silica tends to suppress the occurrence of burrs when the cured product is formed. In particular, it is preferable that the inorganic filler contains fine silica, for example, silica having an average particle size of 0.01 μm to 2.0 μm, more preferably 0.1 μm to 1.5 μm, and even more preferably 0.2 μm to 1.0 μm. From the viewpoint of reducing the elastic modulus and the linear expansion coefficient, it is preferable that the inorganic filler contains large particle size silica. The large particle size silica is preferably silica having a particle size of more than 2.0 μm and not more than 75 μm, more preferably 5.0 μm to 55 μm, and even more preferably 8.0 μm to 20 μm.

[0210] From the viewpoints of reflow resistance and suppression of viscosity increase, the inorganic filler preferably contains silica, and may contain silica as a main component. When the inorganic filler contains silica, the average particle size of the silica is not particularly limited. For example, the volume average particle size of silica is preferably 0.2 μm to 80 μm, more preferably 0.5 μm to 70 μm. When the volume average particle size is 0.2 μm or more, the increase in viscosity of the epoxy resin composition tends to be suppressed. When the volume average particle size is 80 μm or less, the filling ability into narrow gaps tends to be improved. Furthermore, the inorganic filler preferably contains fine silica, for example, silica having an average particle size of 0.01 μm to 2.0 μm, more preferably 0.1 μm to 1.5 μm, and even more preferably 0.2 μm to 1.0 μm. When the inorganic filler contains fine silica, the filling ability into narrow gaps tends to be improved and the occurrence of burrs when the cured product is obtained tends to be suppressed.

[0211] The maximum particle size of the silica is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of the silica is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

[0212] The shape of the silica is not particularly limited, but from the viewpoint of kneadability of the epoxy resin composition, the silica particle shape is preferably spherical.

[0213] When the inorganic filler contains silica, the content of silica is not particularly limited and may be 70% to 100% by mass, 80% to 100% by mass, or 90% to 100% by mass relative to the total mass of the inorganic filler. When silica is used in combination with alumina, the content of silica may be 0.1% to 10% by mass, 0.2% to 5% by mass, or 0.3% to 2% by mass relative to the total mass of the inorganic filler.

[0214] [Various additives] The epoxy resin composition according to the second embodiment may contain, in addition to the above-mentioned components, various additives such as a coupling agent, an ion exchanger, a release agent, a flame retardant, a colorant, and a stress relaxation agent. The epoxy resin composition may contain various additives known in the art as needed. Details of the various additives are the same as those of the various additives in the first embodiment.

[0215] In particular, the epoxy resin composition according to the second embodiment contains a release agent, and the content of the release agent is preferably more than 0% by mass and not more than 2.0% by mass, more preferably more than 0% by mass and not more than 1.5% by mass, and even more preferably more than 0% by mass and not more than 1.2% by mass, relative to the total mass of the epoxy resin composition. By containing the release agent at the above content, it tends to be possible to suppress significant deterioration in appearance, adhesive strength, and laser markability, compared to when a release agent is contained in a content greater than the above content. Furthermore, according to the epoxy resin composition according to the second embodiment, good release properties tend to be able to be maintained even when the content of the release agent is within the above range.

[0216] [Method for preparing epoxy resin composition] There are no particular limitations on the method for preparing the epoxy resin composition according to the second embodiment, and the details of the method for preparing the epoxy resin composition according to the second embodiment are the same as those of the method for preparing the epoxy resin composition according to the first embodiment.

[0217] In the description of the epoxy resin composition according to the second embodiment, where the description of the first embodiment is applied, "first embodiment" will be read as "second embodiment."

[0218] (3) Third embodiment <Sealing epoxy resin composition> An encapsulating epoxy resin composition according to the third embodiment (hereinafter also simply referred to as an epoxy resin composition) contains an epoxy resin, an inorganic filler containing alumina, and a curing agent containing a compound represented by the following general formula (B) (i.e., a "specific curing agent"):

[0219] [ka]

[0220] In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10.

[0221] It has been found that the epoxy resin composition according to the third embodiment makes it possible to produce a cured product with excellent thermal conductivity and flexural strength. The reason for this is not entirely clear, but it can be considered as follows. The epoxy resin composition according to the third embodiment contains a curing agent containing a compound represented by general formula (B). This compound has good wettability with respect to alumina, and it is thought that when the epoxy resin composition according to the third embodiment is cured, good interfacial bonding between the alumina and the resin is achieved. As a result, it is thought that the heat dissipation properties of the alumina are well exhibited. Similarly, it is thought that good interfacial bonding between the alumina and the resin also contributes to improving the flexural strength of the cured product.

[0222] The epoxy resin composition according to the third embodiment may further contain a curing accelerator, other additives, etc. Components that may be contained in the epoxy resin composition according to the third embodiment will be described in detail below.

[0223] [Epoxy resin] The epoxy resin composition according to the third embodiment contains an epoxy resin. The type of epoxy resin is not particularly limited as long as it has two or more epoxy groups in one molecule. Specifically, novolac epoxy resins (phenol novolac epoxy resins, orthocresol novolac epoxy resins, etc.) are obtained by epoxidizing novolac resins obtained by condensing or co-condensing, under an acid 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 are obtained by epoxidizing triphenylmethane phenolic resins obtained by condensing or co-condensing, under an acid catalyst, the above phenolic compounds with aromatic aldehyde compounds such as benzaldehyde, salicylaldehyde, etc.; and novolac resins obtained by co-condensing, under an acid catalyst, the above phenolic compounds and naphthol compounds with an aldehyde compound, etc., are epoxidized. diphenylmethane-type epoxy resins, which are diglycidyl ethers of bisphenol A, bisphenol F, etc.; biphenyl-type epoxy resins, which are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; stilbene-type epoxy resins, which are diglycidyl ethers of stilbene-based phenolic compounds; sulfur-containing epoxy resins, which are diglycidyl ethers of bisphenol S, etc.; 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 the active hydrogen bonded to the nitrogen atom of aniline, diaminodiphenylmethane, isocyanuric acid, etc. is substituted with a glycidyl group; and dicyclopentadiene-type epoxy resins, which are epoxidized co-condensation resins of dicyclopentadiene and phenolic compounds.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 produced by epoxidizing the olefin bonds 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 phenolic resins, which are glycidyl ethers of dicyclopentadiene-modified phenolic resins. Examples of suitable epoxy resins include pentadiene-modified epoxy resins, cyclopentadiene-modified epoxy resins, which are glycidyl ethers of cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified epoxy resins, which are glycidyl ethers of polycyclic aromatic ring-modified phenolic resins; naphthalene-type epoxy resins, which are glycidyl ethers of naphthalene ring-containing phenolic resins; halogenated phenol novolac-type epoxy resins; hydroquinone-type epoxy resins; trimethylolpropane-type epoxy resins; linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid; and aralkyl-type epoxy resins obtained by epoxidizing aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins. Further examples of suitable epoxy resins include epoxidized silicone resins and epoxidized acrylic resins. These epoxy resins may be used alone or in combination of two or more.

[0224] Among the above epoxy resins, from the viewpoint of a balance between reflow resistance and fluidity, epoxy resins selected from the group consisting of biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, sulfur-atom-containing epoxy resins, novolac-type epoxy resins, dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, copolymer-type epoxy resins, and aralkyl-type epoxy resins (these are referred to as "specific epoxy resins"). The specific epoxy resins may be used alone or in combination of two or more.

[0225] When the epoxy resin contains a specific epoxy resin, the total content of the specific epoxy resin is preferably 30% by mass or more, and more preferably 50% by mass or more, of the total epoxy resin, from the viewpoint of exhibiting the performance of the specific epoxy resin.

[0226] Among the specific epoxy resins, biphenyl-type epoxy resins, stilbene-type epoxy resins, diphenylmethane-type epoxy resins, and sulfur-atom-containing epoxy resins are more preferred from the viewpoint of fluidity, and dicyclopentadiene-type epoxy resins, triphenylmethane-type epoxy resins, and aralkyl-type epoxy resins are preferred from the viewpoint of heat resistance.

[0227] In a preferred embodiment, the epoxy resin composition may contain at least one selected from the group consisting of diphenylmethane type epoxy resins and biphenyl type epoxy resins. When the epoxy resin composition contains a diphenylmethane type epoxy resin, the content of the diphenylmethane type epoxy resin may be 40% by mass to 100% by mass, 50% by mass to 100% by mass, or 60% by mass to 100% by mass, relative to the total mass of the epoxy resin. When the epoxy resin composition contains a biphenyl-type epoxy resin, the content of the biphenyl-type epoxy resin may be 20% by mass to 100% by mass, or 25% by mass to 100% by mass, based on the total mass of the epoxy resin.

[0228] In a preferred embodiment, a diphenylmethane type epoxy resin and a biphenyl type epoxy resin may be used in combination. In this case, the total content of the diphenylmethane type epoxy resin and the biphenyl type epoxy resin relative to the total mass of the epoxy resins is preferably 70 mass% or more, more preferably 80 mass% or more, and even more preferably 90 mass% or more. When a diphenylmethane type epoxy resin and a biphenyl type epoxy resin are used in combination, the content ratio of the diphenylmethane type epoxy resin to the biphenyl type epoxy resin (diphenylmethane type epoxy resin:biphenyl type epoxy resin) may be 90:10 to 10:90 or 80:20 to 50:50 by mass.

[0229] The details of the preferably used biphenyl type epoxy resin, stilbene type epoxy resin, diphenylmethane type epoxy resin, sulfur atom-containing type epoxy resin, novolac type epoxy resin, dicyclopentadiene type epoxy resin, triphenylmethane type epoxy resin, copolymer type epoxy resin, and aralkyl type epoxy resin are as described in the first embodiment.

[0230] The epoxy equivalent of the epoxy resin is not particularly limited. From the viewpoint of the 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.

[0231] When the epoxy resin is solid, its softening point or melting point is not particularly limited. From the viewpoints of moldability and reflow resistance, it is preferably 40°C to 180°C, and from the viewpoint of handleability during preparation of the epoxy resin composition, it is more preferably 50°C to 130°C. The melting point of the epoxy resin is a value measured by differential scanning calorimetry (DSC), and the softening point of the epoxy resin is a value measured by a method (ring and ball method) in accordance with JIS K 7234:1986.

[0232] The content of the epoxy resin in the epoxy resin composition is preferably 0.5% by mass to 50% by mass, more preferably 2% by mass to 30% by mass, from the viewpoints of strength, fluidity, heat resistance, moldability, etc.

[0233] [Inorganic filler] The epoxy resin composition according to the third embodiment contains an inorganic filler containing alumina. As the inorganic filler, alumina may be used alone, or alumina may be used in combination with another inorganic filler.

[0234] The average particle diameter of the inorganic filler is not particularly limited. For example, the volume average particle diameter is preferably 0.2 μm to 80 μm, more preferably 0.5 μm to 70 μm, and even more preferably 1 μm to 50 μm. When the volume average particle diameter is 0.2 μm or more, an increase in the viscosity of the epoxy resin composition tends to be suppressed. When the volume average particle diameter is 80 μm or less, the ability to fill narrow gaps tends to be improved. The volume average particle diameter of the inorganic filler can be measured as the volume average particle diameter (D50) using a laser diffraction scattering particle size distribution analyzer. From the viewpoint of the flowability of the epoxy resin composition, it is preferable that the particle diameter of the inorganic filler be distributed over a wide range.

[0235] Specifically, the volume average particle size of the inorganic filler in the epoxy resin composition or the cured product thereof can be measured by the following method. The crucible containing the epoxy resin composition or its cured product is placed in a muffle furnace and heated to 800°C. The sample is left for approximately 4 hours until it is completely incinerated. The sample is allowed to cool naturally until it returns to room temperature, and the ash (inorganic filler) is extracted. The inorganic filler is thoroughly dispersed using an ultrasonic disperser or the like to prepare a dispersion. Using this dispersion, the volume-average particle size of the inorganic filler can be measured from the volume-based particle size distribution measured using a laser diffraction / scattering particle size distribution analyzer.

[0236] The maximum particle size (also referred to as the cut point) of the inorganic filler is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of the inorganic filler is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

[0237] The shape of the inorganic filler is not particularly limited, but from the viewpoint of the flowability of the epoxy resin composition, the particle shape of the inorganic filler is preferably spherical.

[0238] The content of the inorganic filler is not particularly limited. The content of the inorganic filler is preferably 50% by volume or more, more preferably 60% by volume or more, even more preferably 70% by volume or more, particularly preferably 75% by volume or more, and extremely preferably 80% by volume or more, based on the total volume of the epoxy resin composition. When the content of the inorganic filler is 50% by volume or more based on the total volume of the epoxy resin composition, the properties of the cured product, such as the thermal expansion coefficient, thermal conductivity, and elastic modulus, tend to be further improved. Furthermore, the content of the inorganic filler is preferably 95% by volume or less, more preferably 90% by volume or less, and even more preferably 87% by volume or less, based on the total volume of the epoxy resin composition. When the content of the inorganic filler is 95% by volume or less of the total volume of the epoxy resin composition, an increase in viscosity of the epoxy resin composition is suppressed, and the flowability is further improved, tending to result in better moldability. From the above viewpoints, the content of the inorganic filler is preferably 50% by volume to 95% by volume, more preferably 60% by volume to 95% by volume, even more preferably 70% by volume to 95% by volume, particularly preferably 75% by volume to 90% by volume, and extremely preferably 80% by volume to 87% by volume, relative to the total volume of the epoxy resin composition.

[0239] Furthermore, the epoxy resin composition according to the third embodiment tends to be able to be kneaded well even when the content of the inorganic filler is, for example, 82 vol% or more, more preferably 84 vol% or more, even more preferably 85 vol% or more, particularly preferably 86 vol% or more, and extremely preferably 87 vol% or more of the epoxy resin composition.

[0240] Furthermore, the epoxy resin composition according to the third embodiment tends to be able to be kneaded well even when the content of the inorganic filler is, for example, 90% by mass or more, more preferably 92% by mass or more, even more preferably 94% by mass or more, particularly preferably 96% by mass or more, and extremely preferably 98% by mass or more of the epoxy resin composition.

[0241] -alumina- The inorganic filler includes alumina. The average particle size of the alumina is not particularly limited. For example, the volume average particle size of the alumina is preferably 0.2 μm to 80 μm, and more preferably 0.5 μm to 70 μm. When the volume average particle size is 0.2 μm or more, an increase in viscosity of the epoxy resin composition tends to be suppressed. When the volume average particle size is 80 μm or less, the ability to fill narrow gaps tends to be improved. From the viewpoint of the flowability of the epoxy resin composition, it is preferable that the particle size of the alumina is distributed over a wide range.

[0242] The maximum particle size (also referred to as the cut point) of the alumina is not particularly limited. From the viewpoint of filling narrow gaps, the maximum particle size of the alumina is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

[0243] In a preferred embodiment, alumina having an average particle size of 0.1 μm to 2.0 μm, preferably 0.2 μm to 1.5 μm, more preferably 0.3 μm to 1.0 μm, and alumina having an average particle size of more than 2.0 μm to 75 μm or less, preferably 5.0 μm to 55 μm, more preferably 8.0 μm to 20 μm, may be used in combination. By using two or more types of alumina having different average particle sizes in combination, it tends to be possible to achieve favorable filling properties and flowability.

[0244] The shape of the alumina is not particularly limited, but from the viewpoint of the flowability of the epoxy resin composition, the alumina particles are preferably spherical.

[0245] From the viewpoint of high thermal conductivity, the alumina content relative to the total mass of the inorganic filler is preferably 75% by mass or more, more preferably 80% by mass or more, even more preferably 85% by mass or more, particularly preferably 90% by mass or more, and extremely preferably 95% by mass or more. Also, from the viewpoints of low viscosity and ease of kneading, the alumina content relative to the total mass of the inorganic filler is preferably 99.9% by mass or less, more preferably 99.8% by mass or less, and even more preferably 99.7% by mass or less.

[0246] -Other inorganic fillers- The epoxy resin composition according to the third embodiment may contain an inorganic filler other than alumina. The type of inorganic filler other than alumina is not particularly limited. Specific examples include inorganic materials such as silica (fused silica, crystalline silica, etc.), glass, 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 composite hydroxides of magnesium and zinc, and zinc borate. Among these, silica is preferred from the viewpoints of flowability and a reduced linear expansion coefficient, and fused silica is more preferred. The inorganic filler may be in the form of a powder, beads formed by spheroidizing the powder, or fibers.

[0247] The inorganic filler preferably contains silica in addition to alumina. When the inorganic filler contains silica, the viscosity tends to decrease and the kneadability and flowability tend to be improved. The use of particularly fine silica tends to suppress the occurrence of burrs when the cured product is formed. In particular, the inorganic filler preferably contains fine silica, for example, silica having an average particle diameter of 2.0 μm or less, preferably an average particle diameter of 0.01 μm to 2.0 μm, more preferably 0.1 μm to 1.5 μm, and particularly preferably 0.2 μm to 1.0 μm. From the viewpoint of reducing the modulus of elasticity and the coefficient of linear expansion, the inorganic filler may contain large particle silica. Examples of large particle silica include large particle silica having an average particle diameter of more than 2.0 μm but not exceeding 75 μm, preferably 5.0 μm to 55 μm, and more preferably 8.0 μm to 20 μm.

[0248] When the inorganic filler contains silica, from the viewpoint of kneadability and fillability, the maximum particle size of the silica is preferably 150 μm or less, more preferably 75 μm or less, and even more preferably 55 μm or less.

[0249] When the inorganic filler contains silica, the content of silica is preferably 0.1% by mass to 3.0% by mass, more preferably 0.1% by mass to 2.0% by mass, and even more preferably 0.1% by mass to 1.0% by mass, relative to the total mass of the inorganic filler.

[0250] Generally, when an epoxy resin composition contains particulate silica, the viscosity tends to increase. However, the epoxy resin composition according to the third embodiment has been found to have a low viscosity, and even when particulate silica is contained, the increase in viscosity tends to be effectively suppressed.

[0251] [Hardening agent] The epoxy resin composition according to the third embodiment contains a curing agent containing the compound (specific curing agent) represented by the general formula (B) described above. The curing agent may further contain other curing agents in addition to the specific curing agent. The details of the curing agent are the same as those of the curing agent according to the first embodiment.

[0252] [Curing accelerator] The epoxy resin composition according to the third embodiment may contain a curing accelerator. The type of the curing accelerator is not particularly limited. The details of the curing accelerator are the same as those of the curing accelerator according to the first embodiment.

[0253] [Various additives] The epoxy resin composition according to the third embodiment may contain various additives such as a coupling agent, an ion exchanger, a mold release agent, a flame retardant, a colorant, and a stress relaxation agent in addition to the above-mentioned components. The epoxy resin composition may contain various additives known in the art as needed. Details of the various additives are the same as those of the various additives in the first embodiment.

[0254] [Method for preparing epoxy resin composition] There are no particular limitations on the method for preparing the epoxy resin composition according to the third embodiment, and the details of the method for preparing the epoxy resin composition according to the third embodiment are the same as those of the method for preparing the epoxy resin composition according to the first embodiment.

[0255] [Uses of epoxy resin composition] The epoxy resin composition according to the third embodiment is used for sealing elements. The method for sealing elements is not particularly limited, and may be transfer molding, injection molding, compression molding, or the like.

[0256] [Characteristics of Epoxy Resin Composition] It has been found that the epoxy resin composition according to the third embodiment tends to have excellent kneadability. While the reason for this is not entirely clear, it is thought that the good dispersibility of inorganic filler particles and the suppression of friction between the inorganic fillers make it difficult for shear heat to occur during kneading, thereby suppressing thickening of the epoxy resin composition due to shear heat. Therefore, even if the content of inorganic filler is increased, the epoxy resin composition tends to be prepared satisfactorily. Furthermore, particularly when the epoxy resin composition according to the third embodiment is subjected to compression molding, the content of the release agent is generally increased to maintain kneadability. However, with the epoxy resin composition according to the third embodiment, good kneadability tends to be maintained even if the content of the release agent is reduced (for example, 3.0 mass % or less, preferably 2.0 mass % or less, more preferably 1.5 mass % or less, relative to the total mass of the epoxy resin), from the viewpoints of reducing surface contamination of molded products, maintaining adhesive strength, maintaining laser marking properties, and the like.

[0257] (Liquidity) It has been found that the epoxy resin composition according to the third embodiment tends to have excellent fluidity. Although the reason for this is not entirely clear, it is thought that the resin component has good wettability with the inorganic filler, which improves the dispersion state of the fine inorganic filler and suppresses thickening due to friction. Therefore, for example, when the epoxy resin composition according to the third embodiment is subjected to transfer molding, it is advantageous because the epoxy resin composition has excellent fluidity even when it contains a high proportion of inorganic filler.

[0258] When an epoxy resin composition is molded using a spiral flow measurement mold conforming to MMI-1-66 under conditions of a mold temperature of 175°C, a molding pressure of 6.9 MPa, and a curing time of 90 seconds, the flow distance (inches) is preferably 40.0 inches (1016 mm) or more, more preferably 46.0 inches (1168 mm) or more, and even more preferably 48.0 inches (1219 mm) or more. The flow distance may also be 70 inches (1778 mm) or less. Specifically, the measurement is carried out by the method described in the Examples.

[0259] When 5 g of the epoxy resin composition is compression molded using a flat plate mold for disk flow measurement under conditions of 180°C, a load of 78 N, and a cure time of 90 seconds, the disk flow is preferably 80.0 mm or more, more preferably 86.0 mm or more, even more preferably 88.0 mm or more, and particularly preferably 90.0 mm or more. Alternatively, the disk flow may be 160 mm or less. Specifically, the measurement is carried out by the method described in the Examples.

[0260] (Solubility) It has been found that the epoxy resin composition according to the third embodiment tends to have excellent solubility, and therefore, for example, when the epoxy resin composition according to the third embodiment is subjected to compression molding, it is preferable because it improves the ability to fill narrow passages.

[0261] The solubility can be evaluated, for example, by the method described in the Examples. The solubility measured by the method described in the Examples is preferably 40% or less, more preferably 35% or less.

[0262] [Properties of the cured product] (thermal conductivity) The thermal conductivity of the epoxy resin composition when cured is not particularly limited. From the viewpoint of obtaining the desired heat dissipation properties, the thermal conductivity at room temperature (25°C) may be 3.0 W / (m·K) or more, 4.0 W / (m·K) or more, 5.0 W / (m·K) or more, 5.4 W / (m·K) or more, 6.0 W / (m·K) or more, 7.0 W / (m·K) or more, 8.0 W / (m·K) or more, 9.0 W / (m·K) or more, or even 10.0 W / (m·K) or more. The thermal conductivity of the cured product can be measured by the xenon flash (Xe-flash) method (e.g., using a Hyper Flash instrument, trade name: LFA467, manufactured by NETZSCH).

[0263] (bending strength) The flexural strength of the cured product of the epoxy resin composition is not particularly limited. For example, the flexural strength of the cured product is preferably 100 MPa or more, more preferably 150 MPa or more, even more preferably 160 MPa or more, and particularly preferably 165 MPa or more. The upper limit of the flexural strength is not particularly limited, and may be, for example, 250 MPa or less. The flexural strength of the cured product can be measured, for example, by the method described in the Examples.

[0264] In the description of the encapsulating epoxy resin composition according to the third embodiment, where the description of the first embodiment is applied, "first embodiment" will be read as "third embodiment."

[0265] <Electronic component equipment> The electronic component device includes an element and a cured product of the epoxy resin composition according to any one of the first to third embodiments that seals the element. Examples of electronic component devices include devices obtained by mounting elements (active elements such as semiconductor chips, transistors, diodes, and thyristors, and passive elements such as capacitors, resistors, and coils) on a support member such as a lead frame, a pre-wired tape carrier, a wiring board, glass, a silicon wafer, or an organic substrate, and then sealing the resulting element part with an epoxy resin composition. More specifically, typical resin-sealed ICs such as DIP (Dual Inline Package), PLCC (Plastic Leaded Chip Carrier), QFP (Quad Flat Package), SOP (Small Outline Package), SOJ (Small Outline J-lead package), TSOP (Thin Small Outline Package), and TQFP (Thin Quad Flat Package) have a structure in which an element is fixed on a lead frame, and terminal portions of the element such as bonding pads and leads are connected by wire bonding, bumps, or the like, and then sealed with an epoxy resin composition; TCP (Tape Carrier Package) has a structure in which an element connected to a tape carrier by bumps is sealed with an epoxy resin composition; and COB (Chip On Board) has a structure in which an element is connected to wiring formed on a support member by wire bonding, flip chip bonding, solder, or the like, and then sealed with an epoxy resin composition. Examples of suitable printed wiring boards include BGA (Ball Grid Array), CSP (Chip Size Package), and MCP (Multi Chip Package), which have a structure in which elements are mounted on the surface of a support member having terminals for connecting a wiring board formed on the back surface thereof, the elements are connected to wiring formed on the support member by bump or wire bonding, and the elements are then sealed with an epoxy resin composition. Epoxy resin compositions can also be suitably used in printed wiring boards.

[0266] Methods for encapsulating electronic component devices using epoxy resin compositions include low-pressure transfer molding, injection molding, and compression molding. Among these, low-pressure transfer molding is the most common. However, in the second embodiment, the electronic component device is encapsulated by compression molding.

[0267] <Method for manufacturing electronic component device> The method for manufacturing an electronic component device includes encapsulating an element with the epoxy resin composition according to any one of the first to third embodiments. The encapsulation method for the element is not particularly limited, and examples thereof include the molding methods described above. However, in the second embodiment, the encapsulation of the electronic component device is performed by compression molding. [Example]

[0268] Hereinafter, embodiments of the present disclosure will be specifically described using examples, but the embodiments of the present disclosure are not limited to these examples.

[0269] 1. Example of the First Embodiment [Preparation of Epoxy Resin Composition] <Examples 1-1 to 1-8 and Comparative Examples 1-1 to 1-5> The epoxy resin compositions of Examples 1-1 to 1-8 and Comparative Examples 1-1 to 1-5 were prepared by mixing the following materials in the compositions (parts by mass) shown in Table 1 and performing roll kneading at a kneading temperature of 80° C. Note that "-" in Table 1 means that the corresponding component was not blended.

[0270] (epoxy resin) Epoxy resin 1: Orthocresol novolac epoxy resin with an epoxy equivalent weight of 197 g / eq (Chang Chun Plastic Co., Ltd., product name "CNE-195LLB") Epoxy resin 2: Methoxynaphthalene-cresol-formaldehyde co-condensation epoxy resin with an epoxy equivalent of 250 g / eq and a softening point of 58°C (DIC Corporation, product name "HP-5000")

[0271] (hardening agent) Curing agent 1: Orthocresol novolac resin with a hydroxyl equivalent of 116 g / eq and a softening point of 64°C (Meiwa Kasei Co., Ltd., product name "MEH-5100-5S") Curing agent 2: Orthocresol novolac resin with a hydroxyl equivalent of 117 g / eq and a softening point of 70°C (Meiwa Kasei Co., Ltd., prototype) Curing agent 3: Orthocresol novolac resin with a hydroxyl equivalent of 117 g / eq and a softening point of 81°C (DIC Corporation, product name "KA-1160") Curing agent A: Novolac phenolic resin with a hydroxyl equivalent of 103 g / eq to 107 g / eq and a softening point of 67°C to 75°C (Meiwa Kasei Co., Ltd., product name "H-4")

[0272] (curing accelerator) Curing accelerator: Addition product of triphenylphosphine and 1,4-benzoquinone (inorganic filler) Fused silica (spherical fused silica, average particle size 17.5 μm, specific surface area 3.8 m 2 / g) (coupling agent) Coupling agent: Epoxysilane (γ-glycidoxypropyltrimethoxysilane) (coloring agent) Carbon black (Mitsubishi Chemical Corporation, product name "MA-100") (mold release agent) Carnauba wax (Cerarica NODA Co., Ltd.)

[0273] [Table 1]

[0274] [Evaluation of Epoxy Resin Composition] The properties of the epoxy resin compositions prepared in Examples 1-1 to 1-8 and Comparative Examples 1-1 to 1-5 were evaluated by the following property tests. The evaluation results are shown in Table 2 below. Unless otherwise specified, the epoxy resin compositions were molded 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 90 seconds. If necessary, post-curing was performed at 175°C for 5 hours.

[0275] (1) Spiral flow The epoxy resin composition was molded under the above conditions using a spiral flow measurement mold conforming to EMMI-1-66, and the flow distance (cm) was determined.

[0276] (2) Hardness when heated The epoxy resin composition was molded under the above conditions into a disk having a diameter of 50 mm and a thickness of 3 mm, and immediately after molding, the Shore D hardness was measured using a Shore D hardness tester (Ueshima Seisakusho Co., Ltd., HD-1120 (Type D)).

[0277] (3) Elastic modulus measurement at 260°C The epoxy resin composition was molded into a size of 50 mm long x 5 mm wide x 2 mm thick under the above conditions and post-cured under the same conditions. The viscoelasticity was then measured using a viscoelasticity measuring device RSA-3 (TA Instruments) in three-point bending mode at a heating rate of 10°C / min and a frequency of 1 Hz. The elastic modulus (GPa) at 260°C was read from the measurement results.

[0278] (4) Water absorption rate The disk molded in (2) above was post-cured under the above conditions. The resulting disk was then left to stand for 168 hours under conditions of 85°C and 60% RH (relative humidity), and the change in mass before and after standing was measured. The water absorption rate was calculated from the measurement results using the following formula: Water absorption rate (mass%) = [(mass of disc after standing - mass of disc before standing) / mass of disc before standing] × 100

[0279] (5) Reflow resistance An 80-pin flat package (QFP) with dimensions of 20 mm × 14 mm × 2 mm (lead frame material: copper alloy, die pad top surface and lead tips silver-plated) mounted with an 8 mm × 10 mm × 0.4 mm silicon chip was molded using the epoxy resin composition and post-cured under the conditions described above. The resulting packages were humidified at 85°C and 60% RH for 168 hours. Subsequently, reflow treatments were performed at predetermined temperatures (250°C, 260°C, and 270°C) for 10 seconds. The presence or absence of external cracks on the package was visually observed, and the presence or absence of internal delamination on the package was observed using an ultrasonic flaw detector (Hitachi Construction Machinery Co., Ltd., HYE-FOCUS). Reflow resistance was evaluated by the total number of packages that exhibited either cracking or delamination out of 10 tested packages.

[0280] [Table 2]

[0281] As shown in Tables 1 and 2, by using the epoxy resin compositions of Examples 1-1 to 1-8 containing curing agents 1 to 3, the high-temperature elastic modulus was reduced and reflow resistance was improved compared to the epoxy resin compositions of Comparative Examples 1-1 to 1-5 not containing curing agents 1 to 3. The degree of reduction in high-temperature elastic modulus was greater than expected from the resin structure and hydroxyl group equivalent. This is thought to have resulted in better-than-expected reflow resistance. Furthermore, the reduction in elastic modulus of Example 1-5, which used curing agent 1 as part of the curing agent, was greater than expected from the blending ratio, and better-than-expected reflow resistance was exhibited even when a specific curing agent was used as part of the curing agent.

[0282] <Examples 1-9 to 1-10 and Comparative Examples 1-6 to 1-10> [Preparation of Epoxy Resin Composition] The epoxy resin compositions of the Examples and Comparative Examples were prepared by mixing the following materials in the compositions shown in Tables 3 and 4 and kneading them using a twin-screw kneader at a kneading temperature of 100°C. Note that "-" in the tables below means that the component was not blended.

[0283] (epoxy resin) Epoxy resin 1: Diphenylmethane type epoxy resin (product name: YSLV-80XY, Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent weight 190 g / eq) Epoxy resin 2: Biphenyl-type epoxy resin (product name: YX-4000, Mitsubishi Chemical Corporation, epoxy equivalent weight 190 g / eq) Epoxy resin 3: Triphenylmethane type epoxy resin (multifunctional type (product name: 1032H60, Mitsubishi Chemical Corporation, epoxy equivalent weight 170 g / eq))

[0284] (hardening agent) Hardener 1: Novolac phenolic resin (product name: H-4, Meiwa Kasei Co., Ltd., hydroxyl equivalent: 103 g / eq to 107 g / eq, softening point: 67°C to 75°C) Curing agent 2: Aralkyl phenolic resin (product name: MEHC7800-4S, Meiwa Kasei Co., Ltd., hydroxyl equivalent 167g / eq to 179g / eq, softening point 61°C to 65°C) Curing agent 3: Orthocresol novolac resin (product name: MEH5100-5S, Meiwa Kasei Co., Ltd., hydroxyl equivalent 116 g / eq, softening point 65°C; compound represented by general formula (B)) Curing agent 4: Aralkyl phenolic resin (product name: MEHC7851-SS, Meiwa Kasei Co., Ltd., hydroxyl equivalent 201g / eq to 205g / eq, softening point 64°C to 69°C) Hardener 5: Triphenylmethane phenolic resin (product name: MEH-7500-3S, Meiwa Kasei Co., Ltd., hydroxyl equivalent: 103 g / eq)

[0285] (Inorganic filler) Inorganic filler 1: Fine particle alumina (average particle size 0.4 μm, maximum particle size 2.0 μm) Inorganic filler 2: Large particle alumina (average particle size 10 μm, maximum particle size 75 μm) Inorganic filler 3: Ultrafine silica (average particle size 0.1 μm) Inorganic filler 4: fine particle silica (average particle size 0.4 μm, maximum particle size 2.0 μm) Inorganic filler 5: Large particle silica (average particle size 12 μm, maximum particle size 75 μm)

[0286] (curing accelerator) Curing accelerator: Addition product of triphenylphosphine and 1,4-benzoquinone

[0287] (Other additives) Coupling agent: N-phenyl-3-aminopropyltrimethoxysilane (trade name: KBM-573, Shin-Etsu Chemical Co., Ltd.) Release agent: Carnauba wax Colorant: Carbon black Ion exchanger: Product name: DHT-4A, Kyowa Chemical Industry Co., Ltd.

[0288] [Evaluation of Epoxy Resin Composition] The properties of the epoxy resin compositions prepared in the examples and comparative examples were evaluated by the following property tests. Unless otherwise specified, the epoxy resin compositions were molded 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 90 seconds. If necessary, post-curing was performed at 175°C for 5 hours.

[0289] (1) Spiral flow The epoxy resin composition was molded under the above conditions using a spiral flow measurement mold conforming to EMMI-1-66, and the flow distance (inches) was determined. Those with a flow distance of 40.0 inches or more were judged to have good fluidity.

[0290] (2) Hardness when heated The epoxy resin composition was molded in a high-temperature vacuum molding machine under conditions of 175°C, 600 seconds, and a pressure of 7 MPa, and the hardness was measured using a Shore D hardness tester (Ueshima Seisakusho Co., Ltd., HD-1120 (Type D)). A hot hardness of 70 or more was considered to indicate good curability.

[0291] (3) Disk flow A disk flow measurement plate mold was used, with an upper mold measuring 200 mm (W) × 200 mm (D) × 25 mm (H) and a lower mold measuring 200 mm (W) × 200 mm (D) × 15 mm (H). Five grams of epoxy resin composition was weighed on a balance and placed in the center of the lower mold heated to 180°C. After five seconds, the upper mold, also heated to 180°C, was closed and compression molded under a load of 78 N and a cure time of 90 seconds. The major and minor axes of the molded product were measured with calipers, and the average value (mm) was taken as the disk flow. A disk flow of 80 mm or greater was considered to have good fluidity.

[0292] (4) Melt viscosity at 175°C (ηFT) The epoxy resin composition was heated to melt, and the melt viscosity at 175°C was measured using a Koka type flow tester. A melt viscosity of 250 Pa·s or less was determined to be low viscosity.

[0293] (5) Thermal conductivity Using the epoxy resin composition, semiconductor elements were encapsulated in a compression molding machine at a mold temperature of 175-180°C, a molding pressure of 7 MPa, and a curing time of 150 seconds to prepare test specimens for evaluating thermal conductivity. The thermal conductivity of the test specimens was then measured using the xenon flash (Xe-flash) method. A specimen with a thermal conductivity (λ) of 5.0 W / (m·°C) was deemed to have excellent thermal conductivity.

[0294] (6) Bending strength Cured epoxy resin compositions obtained in the examples and comparative examples were cut into rectangular parallelepipeds measuring 2.0 mm x 5.0 mm x 40 mm to prepare test specimens for evaluating flexural strength. These test specimens were subjected to bending tests using a Tensilon universal testing machine (Instron 5948, Instron Corporation) at a support distance of 32 mm and a crosshead speed of 1 mm / min. Using the measurement results, a bending stress-displacement curve was created using equation (1), and the maximum stress was taken as the flexural strength. σ=3FL / 2bh 2 ...Equation (1) σ: Bending stress (MPa) F: Bending load (N) L: Distance between fulcrums (mm) b: Test piece width (mm) h: test piece thickness (mm)

[0295] [Table 3]

[0296] [Table 4]

[0297] As can be seen from Tables 3 and 4, the epoxy resin compositions of the Examples had higher fluidity than the epoxy resin compositions of the Comparative Examples, and even when an inorganic filler with a relatively small particle size was used, an increase in viscosity and a decrease in fluidity were suppressed. Furthermore, the epoxy resin compositions of the Examples also maintained good curability.

[0298] 2. Example of the Second Embodiment

[0299] [Preparation of Epoxy Resin Composition] The epoxy resin compositions of the Examples and Comparative Examples were prepared by mixing the following materials in the compositions shown in Tables 5 and 6 and kneading them using a twin-screw kneader at a kneading temperature of 100°C. Note that "-" in the tables below means that the component was not blended.

[0300] (epoxy resin) Epoxy resin 1: Diphenylmethane type epoxy resin (product name: YSLV-80XY, Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent weight 190 g / eq) Epoxy resin 2: Biphenyl-type epoxy resin (product name: YX-4000, Mitsubishi Chemical Corporation, epoxy equivalent weight 190 g / eq) Epoxy resin 3: Triphenylmethane type epoxy resin (multifunctional type (product name: 1032H60, Mitsubishi Chemical Corporation, epoxy equivalent weight 170 g / eq))

[0301] (hardening agent) Hardener 1: Novolac phenolic resin (product name: H-4, Meiwa Kasei Co., Ltd., hydroxyl equivalent: 103 g / eq to 107 g / eq, softening point: 67°C to 75°C) Curing agent 2: Aralkyl phenolic resin (product name: MEHC7800-4S, Meiwa Kasei Co., Ltd., hydroxyl equivalent 167g / eq to 179g / eq, softening point 61°C to 65°C) Curing agent 3: Orthocresol novolac resin (product name: MEH5100-5S, Meiwa Kasei Co., Ltd., hydroxyl equivalent 116 g / eq, softening point 65°C; compound represented by general formula (B)) Curing agent 4: Aralkyl phenolic resin (product name: MEHC7851-SS, Meiwa Kasei Co., Ltd., hydroxyl equivalent 201g / eq to 205g / eq, softening point 64°C to 69°C) Hardener 5: Triphenylmethane phenolic resin (product name: MEH-7500-3S, Meiwa Kasei Co., Ltd., hydroxyl equivalent: 103 g / eq)

[0302] (Inorganic filler) Inorganic filler 1: Fine particle alumina (average particle size 0.4 μm, maximum particle size 2.0 μm) Inorganic filler 2: Large particle alumina (average particle size 10 μm, maximum particle size 75 μm) Inorganic filler 3: Ultrafine silica (average particle size 0.1 μm) Inorganic filler 4: fine particle silica (average particle size 0.4 μm, maximum particle size 2.0 μm) Inorganic filler 5: Large particle silica (average particle size 12 μm, maximum particle size 75 μm)

[0303] (curing accelerator) Curing accelerator: Addition product of triphenylphosphine and 1,4-benzoquinone

[0304] (Other additives) Coupling agent: N-phenyl-3-aminopropyltrimethoxysilane (trade name: KBM-573, Shin-Etsu Chemical Co., Ltd.) Release agent: Carnauba wax Colorant: Carbon black Ion exchanger: Product name: DHT-4A, Kyowa Chemical Industry Co., Ltd.

[0305] [Evaluation of Epoxy Resin Composition] The properties of the epoxy resin compositions prepared in the Examples and Comparative Examples were evaluated by the following property tests.

[0306] (1) Solubility Approximately 1.5 g of epoxy resin composition powder (3.5 mm mesh pass, 1.0 mm mesh on) was prepared. The epoxy resin composition powder was placed on a hot plate heated to 175°C so that it formed a circular shape in the plane and had a height of approximately 3 mm. A 200 g mold, also heated to 175°C, was then dropped horizontally onto the powder. The upper mold was supported by the lower mold and a vertical support, allowing a constant load to be applied in the plane. The time when the upper mold fell (when the upper mold reached the top surface of the powder) was defined as 0 seconds, and the distance the upper mold fell after the powder began to melt was measured using a laser displacement meter. The height at 0 seconds was defined as A, and the height after 1 second was defined as B. The powder solubility was evaluated by calculating (B / A) x 100 (%). The solubility was judged to be good when the height of the epoxy resin composition was 40% or less in 1 second.

[0307] (2) Hardness when heated The epoxy resin composition was molded in a high-temperature vacuum molding machine under conditions of 175°C, 90 seconds, and a pressure of 7 MPa, and the hardness was measured using a Shore D hardness tester (Ueshima Seisakusho Co., Ltd., HD-1120 (Type D)). A hot hardness of 70 or more was considered to indicate good curability.

[0308] (3) Disk flow A disk flow measurement plate mold was used, with an upper mold measuring 200 mm (W) × 200 mm (D) × 25 mm (H) and a lower mold measuring 200 mm (W) × 200 mm (D) × 15 mm (H). Five grams of epoxy resin composition was weighed on a balance and placed in the center of the lower mold heated to 180°C. After five seconds, the upper mold, also heated to 180°C, was closed and compression molded under a load of 78 N and a cure time of 90 seconds. The major and minor axes of the molded product were measured with calipers, and the average value (mm) was taken as the disk flow. A disk flow of 80 mm or greater was considered to have good fluidity.

[0309] (4) Melt viscosity at 175°C (ηFT) The epoxy resin composition was heated to melt, and the melt viscosity at 175°C was measured using a Koka type flow tester. A melt viscosity of 250 Pa·s or less was determined to be low viscosity.

[0310] (5) Thermal conductivity Using the epoxy resin composition, semiconductor elements were encapsulated in a compression molding machine at a mold temperature of 175-180°C, a molding pressure of 7 MPa, and a curing time of 150 seconds to prepare test specimens for evaluating thermal conductivity. The thermal conductivity of the test specimens was then measured using the xenon flash (Xe-flash) method. A specimen with a thermal conductivity (λ) of 5.0 W / (m·°C) was deemed to have excellent thermal conductivity.

[0311] [Table 5]

[0312] [Table 6]

[0313] As can be seen from Tables 5 and 6, the epoxy resin compositions of the examples had excellent solubility. In addition, the epoxy resin compositions of the examples also maintained good curability. Furthermore, the epoxy resin compositions of the examples obtained good results in both the disk flow and melt viscosity evaluations.

[0314] 3. Example of the Third Embodiment [Preparation of Epoxy Resin Composition] The following materials were mixed in the compositions shown in Table 7, and the mixture was kneaded at a temperature of 100°C using a twin-screw kneader to prepare the epoxy resin compositions of the Examples and Comparative Examples. Note that "-" in Table 7 indicates that the component was not blended.

[0315] (epoxy resin) Epoxy resin 1: Diphenylmethane type epoxy resin (bisphenol type epoxy resin) (trade name: YSLV-80XY, Nippon Steel Chemical & Material Co., Ltd., epoxy equivalent weight 190 g / eq) Epoxy resin 2: Biphenyl-type epoxy resin (product name: YX-4000, Mitsubishi Chemical Corporation, epoxy equivalent weight 190 g / eq)

[0316] (hardening agent) Hardener 1: Novolac phenolic resin (product name: H-4, Meiwa Kasei Co., Ltd., hydroxyl equivalent: 103 g / eq to 107 g / eq, softening point: 67°C to 75°C) Curing agent 2: orthocresol novolac resin (product name: MEH5100-5S, Meiwa Kasei Co., Ltd., hydroxyl equivalent 116 g / eq, softening point 65°C; compound represented by general formula (B)) Curing agent 3: Aralkyl phenolic resin (product name: MEHC7800-4S, hydroxyl equivalent 167g / eq to 179g / eq, softening point 61°C to 65°C) Curing agent 4: Aralkyl phenolic resin (product name: MEHC7851-SS, Meiwa Kasei Co., Ltd., hydroxyl equivalent 201g / eq to 205g / eq, softening point 64°C to 69°C)

[0317] (Inorganic filler) Inorganic filler 1: Fine particle alumina (average particle size 0.4 μm, maximum particle size approximately 2.0 μm) Inorganic filler 2: Large particle alumina (average particle size 10 μm, maximum particle size 75 μm) Inorganic filler 3: Ultrafine silica (average particle size 0.1 μm, maximum particle size approximately 2.0 μm)

[0318] (curing accelerator) Curing accelerator: Phosphorus-based curing accelerator

[0319] (Other additives) Coupling agent: N-phenyl-3-aminopropyltrimethoxysilane (trade name: KBM-573, Shin-Etsu Chemical Co., Ltd.) Release agent: Carnauba wax Colorant: Carbon black Ion exchanger: Hydrotalcite compound (trade name: DHT-4A, Kyowa Chemical Industry Co., Ltd.)

[0320] 〔evaluation〕 The properties of the epoxy resin compositions prepared in the examples and comparative examples were evaluated by the following property tests. Unless otherwise specified, the epoxy resin compositions were molded 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 90 seconds. If necessary, post-curing was performed at 175°C for 5 hours.

[0321] (1) Spiral flow The epoxy resin composition was molded under the above conditions using a spiral flow measurement mold conforming to EMMI-1-66, and the flow distance (inch) was determined.

[0322] (2) Disk flow Using a flat plate mold for disk flow measurement having an upper mold of 200 mm (W) × 200 mm (D) × 25 mm (H) and a lower mold of 200 mm (W) × 200 mm (D) × 15 mm (H), 5 g of epoxy resin composition weighed out with a top-pan balance was placed on the center of the lower mold heated to 180°C. After 5 seconds, the upper mold heated to 180°C was closed and compression molded under conditions of a load of 78 N and a curing time of 90 seconds. The major axis (mm) and minor axis (mm) of the molded product were measured with vernier calipers, and the average value (mm) was taken as the disk flow.

[0323] (3) Evaluation of Bali 15 g of the epoxy resin composition was placed on a mold set at 180°C on a press hot plate and molded for 90 seconds. After molding, the length of the portion through which the epoxy resin composition flowed the longest was measured using calipers in 50 μm, 30 μm, 20 μm, 10 μm, 5 μm, and 2 μm slits made in the mold, and this measurement value was taken as the length of the burr.

[0324] (4) Melt viscosity (ηFT) The melt viscosity of the epoxy resin composition heated to 175°C was measured using a flow tester.

[0325] (5) Bending strength Cured epoxy resin compositions obtained in the examples and comparative examples were cut into rectangular parallelepipeds measuring 2.0 mm x 5.0 mm x 40 mm to prepare test specimens for evaluating bending strength. These test specimens were subjected to bending tests using a Tensilon universal testing machine (Instron 5948, Instron Corporation) at a support distance of 32 mm and a crosshead speed of 1 mm / min. Using the measurement results, a bending stress-displacement curve was created using equation (A), and the maximum stress was taken as the bending strength.

[0326] σ=3FL / 2bh 2 ··· Formula (A)

[0327] σ: Bending stress (MPa) F: Bending load (N) L: Distance between fulcrums (mm) b: Test piece width (mm) h: test piece thickness (mm)

[0328] (6) Thermal conductivity Using the epoxy resin composition, a semiconductor element was encapsulated in a compression molding machine under the following conditions: mold temperature 175°C to 180°C, molding pressure 7 MPa, and curing time 150 seconds, to prepare a test piece for evaluating thermal conductivity.The thermal conductivity of the test piece was then measured by the xenon flash (Xe-flash) method.

[0329] (7) Solubility Approximately 1.5 g of epoxy resin composition powder (3.35 mm mesh pass, 1.0 mm mesh on) was prepared. The epoxy resin composition powder was placed in a circular pattern on a hot plate (lower mold) heated to 175°C, with a height of approximately 3 mm. A 200 g upper mold, also heated to 175°C, was allowed to drop horizontally onto the placed epoxy resin composition. The upper mold was supported by the lower mold and a vertical support, so that a constant load was applied to the surface. The time when the upper mold fell (i.e., the time when the upper mold reached the top surface of the powder) was set as 0 seconds, and the distance the upper mold fell from when the epoxy resin composition powder began to melt was measured using a laser displacement meter. The height of the top surface of the epoxy resin composition at 0 seconds was defined as A, and the height 1 second later as B. The powder solubility was calculated as B / A × 100 (%).

[0330] (8) Mixing ability The temperature of the outlet for discharging the kneaded epoxy resin composition into the mold was set to 60°C, the temperature of the discharged kneaded product was measured, and the degree of temperature rise was used as an index of kneadability.

[0331] [Table 7]

[0332] As can be seen from Table 7, the epoxy resin compositions of the examples had a thermal conductivity of 5.4 W / (m K) or more when cured and a flexural strength of 168 MPa or more, achieving both high thermal conductivity and good flexural strength.

[0333] Furthermore, as can be seen from the spiral flow and disk flow evaluations, the epoxy resin compositions of the examples had excellent fluidity.

[0334] During kneading, the temperature of the epoxy resin composition discharge port was set to 60°C, but shear heat generated by the paddle and the epoxy resin composition caused the temperature of the kneaded material to rise above the set temperature. However, when the temperature of the discharged kneaded material was measured, it was found that the epoxy resin composition of the example was able to maintain a temperature closest to the set value, and it was found that excessive shear heat could be suppressed by using the epoxy resin composition of the example.

[0335] As can be seen from the evaluation of burrs, the examples using ultrafine silica can effectively suppress burrs. Furthermore, even when ultrafine silica is used, the epoxy resin compositions of the examples maintain excellent fluidity.

[0336] The evaluation of the melt viscosity reveals that the epoxy resin compositions of the examples have low melt viscosities.

[0337] The epoxy resin compositions of the examples also have excellent solubility, and are therefore considered suitable for use as epoxy resin compositions for compression molding.

[0338] (Addendum) The present disclosure includes the following aspects. <1> An encapsulating epoxy resin composition comprising an epoxy resin and a curing agent containing a compound represented by the following general formula (B):

[0339] [ka]

[0340] (In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10. <2> The content of the compound represented by the general formula (B) in the curing agent is 30% by mass to 100% by mass. <1> The encapsulating epoxy resin composition according to claim 1. <3> In the general formula (B), R 1 is a methyl group <1> or <2> The encapsulating epoxy resin composition according to claim 1. <4> Mixed with an inorganic filler having a volume average particle size of 2.0 μm or less <1> ~ <3> 10. The encapsulating epoxy resin composition according to claim 9, wherein the epoxy resin composition is a encapsulating epoxy resin composition. <5> The composition further contains an inorganic filler, and the content of the inorganic filler having a particle size of 2.0 μm or less is 5 mass % or more based on the total amount of the inorganic filler. <1> ~ <3> 10. The encapsulating epoxy resin composition according to claim 9, wherein the epoxy resin composition is a encapsulating epoxy resin composition. <6> An element and a device for sealing the element <1> ~ <5> and an electronic component device comprising a cured product of the encapsulating epoxy resin composition according to any one of the above items.

[0341] The present disclosure includes the following aspects. <1> An epoxy resin composition for compression molding, comprising an epoxy resin and a curing agent containing a compound represented by the following general formula (B):

[0342] [ka]

[0343] (In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10. <2> The content of the compound represented by the general formula (B) in the curing agent is 30% by mass to 100% by mass. <1> The epoxy resin composition for compression molding according to claim 1. <3> In the general formula (B), R 1 is a methyl group <1> or <2> The epoxy resin composition for compression molding according to claim 1. <4> The epoxy resin composition for compression molding further contains a release agent, and the content of the release agent is more than 0% by mass and 2.0% by mass or less relative to the total mass of the epoxy resin composition for compression molding. <1> ~ <3> 1. The epoxy resin composition for compression molding according to claim 1 . <5> An element and a device for sealing the element <1> ~ <3> and an electronic component device comprising a cured product of the epoxy resin composition for compression molding according to any one of the above items.

[0344] The present disclosure includes the following aspects. <1> An encapsulating epoxy resin composition comprising an epoxy resin, an inorganic filler containing alumina, and a curing agent containing a compound represented by the following general formula (B):

[0345] [ka]

[0346] (In general formula (B), R 1 each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10. <2> the content of the compound represented by the general formula (B) relative to the total mass of the curing agent is 30% by mass to 100% by mass; <1> The encapsulating epoxy resin composition according to claim 1. <3> In the general formula (B), R 1 is a methyl group <1> or <2> The encapsulating epoxy resin composition according to claim 1. <4> The content of the inorganic filler is 75% by volume or more. <1> ~ <3> 10. The encapsulated epoxy resin composition according to claim 1, wherein the epoxy resin composition is a encapsulated epoxy resin composition. <5> The content of alumina relative to the total mass of the inorganic filler is 75 mass% or more. <1> ~ <4> 10. The encapsulated epoxy resin composition according to claim 1, wherein the epoxy resin composition is a encapsulated epoxy resin composition. <6> The inorganic filler further contains silica, and the average particle size of the silica is 2.0 μm or less. <1> ~ <5> 10. The encapsulated epoxy resin composition according to claim 1, wherein the epoxy resin composition is a encapsulated epoxy resin composition. <7> An element and a device for sealing the element <1> ~ <6> 10. An electronic component device comprising a cured product of the encapsulating epoxy resin composition according to any one of claims 1 to 9. <8> <1> ~ <6> 10. A method for producing an electronic component device, comprising encapsulating an element with the encapsulating epoxy resin composition according to any one of claims 1 to 9. <9> The encapsulation of the element is performed by compression molding. <8> A method for manufacturing the electronic component device according to claim 1.

[0347] The disclosures of Japanese Patent Application Nos. 2019-189706, 2020-020134, and 2020-020135 are incorporated herein by reference in their entirety. All publications, patent applications, and technical standards mentioned in this specification are incorporated by reference into this specification to the same extent as if each individual publication, patent application, or technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. Epoxy resin, and a curing agent containing a compound represented by the following general formula (B), having a hydroxyl group equivalent of 100 g / eq to 130 g / eq, and having a melting point or softening point of 50°C to 75°C. An encapsulating epoxy resin composition in the form of a powder, granules, or tablet. 【Chemical 1】 (In general formula (B), R １ each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10.

2. 2. The encapsulated epoxy resin composition according to claim 1, wherein the content of the compound represented by general formula (B) in the curing agent is 30% by mass to 100% by mass.

3. In the general formula (B), R １ 3. The encapsulated epoxy resin composition according to claim 1, wherein R is a methyl group.

4. 4. The encapsulated epoxy resin composition according to claim 1, further comprising an inorganic filler having a volume average particle size of 2.0 μm or less.

5. Further comprising an inorganic filler, 4. The encapsulated epoxy resin composition according to claim 1, wherein the content of the inorganic filler having a particle size of 2.0 μm or less is 5 mass % or more based on the total amount of the inorganic filler.

6. The encapsulated epoxy resin composition according to any one of claims 1 to 4, further comprising a curing accelerator.

7. Epoxy resin, and a curing agent containing a compound represented by the following general formula (B), having a hydroxyl group equivalent of 100 g / eq to 130 g / eq, and having a melting point or softening point of 50°C to 75°C. An epoxy resin composition for compression molding in the form of powder, granules, or tablets. 【Chemistry 2】 (In general formula (B), R １ each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10.

8. 8. The epoxy resin composition for compression molding according to claim 7, wherein the content of the compound represented by general formula (B) in the curing agent is 30% by mass to 100% by mass.

9. In the general formula (B), R １ 9. The epoxy resin composition for compression molding according to claim 7 or 8, wherein is a methyl group.

10. 10. The epoxy resin composition for compression molding according to claim 7, further comprising a mold release agent, the content of which is more than 0% by mass and not more than 2.0% by mass, relative to the total mass of the epoxy resin composition for compression molding.

11. The epoxy resin composition for compression molding according to any one of claims 7 to 10, further comprising a curing accelerator.

12. Epoxy resin, an inorganic filler containing alumina; and a curing agent containing a compound represented by the following general formula (B), having a hydroxyl group equivalent of 100 g / eq to 130 g / eq, and having a melting point or softening point of 50°C to 75°C. An encapsulating epoxy resin composition in the form of a powder, granules, or tablet. 【Chemistry 3】 (In general formula (B), R １ each independently represents an alkyl group having 1 to 6 carbon atoms, and n represents an integer of 0 to 10.

13. 13. The encapsulated epoxy resin composition according to claim 12, wherein the content of the compound represented by general formula (B) relative to the total mass of the curing agent is 30% by mass to 100% by mass.

14. In the general formula (B), R １ The encapsulated epoxy resin composition according to claim 12 or 13, wherein R is a methyl group.

15. 15. The encapsulated epoxy resin composition according to claim 12, wherein the content of the inorganic filler is 75% by volume or more based on the total volume of the encapsulated epoxy resin composition.

16. 16. The encapsulated epoxy resin composition according to claim 12, wherein the content of alumina relative to the total mass of the inorganic filler is 75 mass% or more.

17. 17. The encapsulated epoxy resin composition according to claim 12, wherein the inorganic filler further comprises silica, and the silica has an average particle size of 2.0 μm or less.

18. The encapsulating epoxy resin composition according to any one of claims 12 to 17, further comprising a curing accelerator.

19. A method for producing an electronic component device, comprising encapsulating an element with the epoxy resin composition according to any one of claims 1 to 18.

20. The method for manufacturing an electronic component device according to claim 19, wherein the element is encapsulated by compression molding.

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