Epoxy resin composition, resin paste, film-type adhesive, printed wiring board, semiconductor chip package, and electronic device

Abstract

This epoxy resin composition comprises a component (A) that is an epoxy resin, a component (B) that is at least one curing agent selected from the group consisting of triazine skeleton-containing phenolic curing agents, active ester-based curing agents, and cyanate ester-based curing agents, and a component (C) that is a compound represented by a prescribed chemical formula and is preferably an imidazole compound.

Description

Epoxy resin composition, resin paste, film-type adhesive, printed wiring board, semiconductor chip package, and electronic device

[0001] The present invention relates to an epoxy resin composition, a resin paste, a film-type adhesive, a printed wiring board, a semiconductor chip package, and an electronic device.

[0002] Epoxy resins have traditionally been used in a wide range of applications, such as insulating materials for electrical and electronic components including semiconductor elements, sealing materials, adhesives, conductive materials, matrix resins for fiber-reinforced plastics, and impregnating and fixing agents for motor coils.

[0003] Among these, epoxy resin compositions, which have excellent adhesive properties and high reliability, are used as adhesives for semiconductor elements and printed wiring boards. The components of such epoxy resin compositions generally include an epoxy resin, a curing agent such as a phenolic resin that is reactive with the epoxy resin, and a curing accelerator that accelerates the reaction between the epoxy resin and the curing agent.

[0004] In recent years, with the increasing performance of electronic devices, build-up layers have been used and multi-layered in electronic circuit board materials such as printed wiring boards, and there are demands for finer and denser wiring, lower dielectric loss tangent to reduce transmission loss, and reduced warpage of the substrate. Furthermore, in the packaging of semiconductor chips using the epoxy resin composition, wafer-level packaging and panel-level packaging have attracted attention for their high productivity and low cost. Even in such packaging, the epoxy resin composition is applied to and cured on a large substrate, so reduced warpage is particularly required. Furthermore, in both applications, the epoxy resin composition is required to have stability during storage and to cure rapidly when heated. Furthermore, heat resistance is also required for the epoxy resin composition, as the heat generation of electronic devices increases with the increasing density of electronic components and the volume of electronic information handled.

[0005] Regarding epoxy resin compositions used as insulating resin materials for wafer-level packages and printed wiring boards, insulating resin materials containing a thermosetting resin, an inorganic filler, and a polymer resin having a glass transition temperature of 30°C or lower and having one or more skeletons selected from a butadiene skeleton, a carbonate skeleton, an acrylic skeleton, and a siloxane skeleton, and further having one or more skeletons selected from an amide skeleton, an imide skeleton, and a urethane skeleton, have been disclosed (see, for example, Patent Document 1). Such insulating resin materials are disclosed to have high dimensional stability and minimal warpage, due to the inorganic filler content being 80 to 95% by mass relative to 100% by mass of the nonvolatile components of the insulating resin material, the inorganic filler having an average particle size of 5 μm or less, and the linear thermal expansion coefficient of the cured product of the insulating resin material being 3 to 30 ppm / °C at 25°C to 150°C. Furthermore, with regard to the stability and rapid curing properties of epoxy resin compositions, a curable composition containing a curing agent for anionic curable compounds, which is an imidazole-based compound having a substituted phenyl group at the 2-position of the imidazole ring, has been disclosed (see, for example, Patent Document 2). It has been disclosed that such a curable composition can selectively cause a curing reaction of the epoxy resin in a high temperature range around 150°C and also has excellent storage stability.

[0006] Japanese Patent No. 7188486 Japanese Patent Application Laid-Open No. 2016-29152

[0007] Conventionally, methods for reducing warpage of substrates have been used, such as introducing a flexible skeleton into the molecules of resin components, such as epoxy resins and polymer resins, which make up the majority of epoxy resin compositions, to alleviate the stress that causes warpage, or incorporating a high concentration of inorganic filler to bring the linear expansion coefficients of the substrate material and the epoxy resin composition closer together to suppress warpage. However, as disclosed in Patent Document 1, when a certain amount of polymer resin having a flexible skeleton with a low glass transition temperature is included in an epoxy resin composition, there is a problem that the glass transition temperature of the cured product is lowered, making it difficult to obtain sufficient heat resistance. Furthermore, when an inorganic filler is included in an epoxy resin composition at a high concentration, there are problems such as limited freedom of formulation and an increased viscosity of the epoxy resin composition, making it difficult to handle.

[0008] Furthermore, the epoxy resin composition disclosed in Patent Document 1 has a problem in that there is room for improvement in achieving both storage stability and curability upon heating. On the other hand, the epoxy resin composition disclosed in Patent Document 2 is shown to be able to achieve both storage stability and curability in a high temperature range of around 150°C, but does not specify any composition that satisfies all of the physical properties, such as low warpage, heat resistance, and strength, required for applications such as printed wiring boards, wafer level packages, and panel level packages, and therefore there is still a problem in that there is room for further study.

[0009] In view of the above-mentioned problems of the prior art, the present invention aims to provide an epoxy resin composition which has both stability during storage and curability upon heating, reduces warpage, and also exhibits high heat resistance and high strength.

[0010] As a result of extensive research, the present inventors have discovered that, as a completely different approach from conventional approaches of reducing warpage by adjusting the resin skeleton or the amount of inorganic filler, adding an imidazole compound having a specific structure as a catalyst to a specific curing agent can provide an epoxy resin composition that is stable during storage and curable upon heating, reduces warpage, and also exhibits high heat resistance and high strength, thereby completing the present invention. That is, the present invention is as follows.

[0011] [1] An epoxy resin composition comprising: component (A): an epoxy resin; component (B): at least one curing agent selected from the group consisting of a triazine skeleton-containing phenolic curing agent, an active ester curing agent, and a cyanate ester curing agent; and component (C): a compound represented by the following formula (1) and / or a compound represented by the following formula (2).

[0012]

[0013]

[0014] In formulas (1) and (2), R １ , R ２ are each independently any one selected from the group consisting of a hydrogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, a halogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, and a cycloalkyl group having 6 to 20 carbon atoms which may have a substituent. １ , R ２ may be the same or different, R １ , R ２may be bonded to form a non-aromatic fused ring. X is any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aralkyl group having 7 to 20 carbon atoms which may have a substituent, and a heteroarylalkyl group having 4 to 20 carbon atoms which may have a substituent. Y and Z are any one selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 20 carbon atoms which may have a substituent, an aryloxy group having 6 to 20 carbon atoms which may have a substituent, and an acyl group having 1 to 20 carbon atoms which may have a substituent. Y and Z may be the same or different, and two or more Ys and two or more Zs may be bonded to form a monocyclic or fused ring. m and n are integers of 1 to 4.

[0015] [2] The epoxy resin composition according to [1] above, further comprising a component (D): a filler. [3] The epoxy resin composition according to [1] above, wherein in the component (C), Y and Z are one selected from the group consisting of a hydrogen atom, a hydroxyl group, a carboxyl group, an alkoxy group having 1 to 20 carbon atoms without a substituent, an alkyl group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent, an alkoxy group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent, an aryl group having 6 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent, an aryloxy group having 6 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent, and an acyl group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent. [4] In the component (C), the compound represented by formula (1) is any one selected from the group consisting of 2-(2-hydroxyphenyl)imidazole, 2-(2-hydroxyphenyl)-4(5)-methylimidazole, 4-ethyl-(2-hydroxyphenyl)-5-methylimidazole, (2-hydroxyphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-(2-hydroxyphenyl)-5-methylimidazole, and 2-(2-hydroxy-3(5)-methoxyphenyl)imidazole, and / or the compound represented by formula (2) is any one selected from the group consisting of 2-(2-hydroxyphenyl)imidazole, 2-(2-hydroxyphenyl)-4(5)-methylimidazole, 4-ethyl-(2-hydroxyphenyl)-5-methylimidazole, 4-butyl-(2-hydroxyphenyl)-5-methylimidazole, and 2-(2-hydroxy-3(5)-methoxyphenyl)imidazole. The epoxy resin composition according to any one of [1] to [3] above, which is any one selected from the group consisting of 2-(2-hydroxyphenyl)benzimidazole, 2-(2-hydroxy-3(5)-methoxyphenyl)benzimidazole, 2-(1-hydroxynaphthalen-2-yl)benzimidazole, 2-(2-hydroxynaphthalen-1-yl)benzimidazole, and 2-(2-hydroxyphenyl)benzimidazole-6-carboxylic acid. [5] The epoxy resin composition according to [4] above, further comprising component (D): a filler. [6] A resin paste comprising the epoxy resin composition according to any one of [1] to [5] above. [7] A film-type adhesive comprising: a support; and a resin layer on the support, the resin layer comprising the epoxy resin composition according to any one of [1] to [5] above.[8] A film-type adhesive comprising: a support; a resin layer on the support, the resin layer comprising the epoxy resin composition described in any one of [1] to [5]; and a protective layer on the resin layer. [9] A printed wiring board having a cured layer of the epoxy resin composition described in any one of [1] to [5].

[10] A semiconductor chip package having a cured layer of the epoxy resin composition described in any one of [1] to [5].

[11] An electronic device having the printed wiring board described in [9].

[12] An electronic device having the semiconductor chip package described in

[10] .

[0016] According to the present invention, it is possible to provide an epoxy resin composition which has both stability during storage and curability upon heating, reduces warpage, and also exhibits high heat resistance and high strength.

[0017] Hereinafter, a mode for carrying out the present invention (hereinafter referred to as "the present embodiment") will be described in detail. The following present embodiment is an example for explaining the present invention, and is not intended to limit the present invention to the following content. The present invention can be carried out by appropriately modifying it within the scope of its gist.

[0018] [Epoxy Resin Composition] The epoxy resin composition according to the present embodiment includes: Component (A): an epoxy resin; Component (B): at least one curing agent selected from the group consisting of a triazine skeleton-containing phenolic curing agent, an active ester curing agent, and a cyanate ester curing agent; and Component (C): a compound represented by the following formula (1) and / or a compound represented by the following formula (2).

[0019]

[0020]

[0021] In formulas (1) and (2), R １ , R ２ are each independently any one selected from the group consisting of a hydrogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, a halogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, and a cycloalkyl group having 6 to 20 carbon atoms which may have a substituent.１ , R ２ may be the same or different, R １ , R ２ may be bonded to form a non-aromatic fused ring. X is any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aralkyl group having 7 to 20 carbon atoms which may have a substituent, and a heteroarylalkyl group having 4 to 20 carbon atoms which may have a substituent. Y and Z are any one selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 20 carbon atoms which may have a substituent, an aryloxy group having 6 to 20 carbon atoms which may have a substituent, and an acyl group having 1 to 20 carbon atoms which may have a substituent. Y and Z may be the same or different, and two or more Ys and two or more Zs may be bonded to form a monocyclic or fused ring. m and n are integers of 1 to 4.

[0022] (Component (A): Epoxy Resin) The epoxy resin composition of the present embodiment contains an epoxy resin (hereinafter, may be referred to as epoxy resin (A) or component (A)). Examples of the epoxy resin (A) include, but are not limited to, bifunctional epoxy resins such as bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol E type epoxy resins, bisphenol AD ​​type epoxy resins, bisphenol AF type epoxy resins, tetrabromobisphenol A type epoxy resins, biphenyl type epoxy resins, bixylenol type epoxy resins, tetrabromobiphenyl type epoxy resins, diphenyl ether type epoxy resins, benzophenone type epoxy resins, phenylbenzoate type epoxy resins, diphenyl sulfide type epoxy resins, diphenyl sulfoxide type epoxy resins, diphenyl sulfone type epoxy resins, diphenyl disulfide type epoxy resins, naphthalene type epoxy resins, anthracene type epoxy resins, hydroquinone type epoxy resins, methylhydroquinone type epoxy resins, dibutylhydroquinone type epoxy resins, resorcinol type epoxy resins, methylresorcinol type epoxy resins, catechol type epoxy resins, and N,N-diglycidylaniline type epoxy resins.

[0023] Further examples include trifunctional epoxy resins such as N,N-diglycidylaminobenzene type epoxy resin, o-(N,N-diglycidylamino)toluene type epoxy resin, and triazine type epoxy resin.

[0024] Further examples include tetrafunctional epoxy resins such as naphthalene-type tetrafunctional epoxy resins, tetraglycidyldiaminodiphenylmethane-type epoxy resins, and diaminobenzene-type epoxy resins.

[0025] Further examples include polyfunctional epoxy resins such as phenol novolac type epoxy resins, cresol novolac type epoxy resins, triphenylmethane type epoxy resins, tetraphenylethane type epoxy resins, dicyclopentadiene type epoxy resins, naphthol aralkyl type epoxy resins, and brominated phenol novolac type epoxy resins.

[0026] Further examples include diepoxy resins such as (poly)ethylene glycol diglycidyl ether, (poly)propylene glycol diglycidyl ether, butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, trimethylolpropane diglycidyl ether, polytetramethylene ether glycol diglycidyl ether, glycerin diglycidyl ether, neopentyl glycol diglycidyl ether, cyclohexane diglycidyl ether, and dicyclopentadiene diglycidyl ether.

[0027] Further examples include triepoxy resins such as trimethylolpropane triglycidyl ether and glycerin triglycidyl ether.

[0028] Further examples include alicyclic epoxy resins such as vinyl(3,4-cyclohexene) dioxide and 2-(3,4-epoxycyclohexyl)-5,1-spiro-(3,4-epoxycyclohexyl)-m-dioxane.

[0029] Further examples include glycidylamine type epoxy resins such as tetraglycidylbis(aminomethyl)cyclohexane.

[0030] Further examples include hydantoin type epoxy resins such as 1,3-diglycidyl-5-methyl-5-ethylhydantoin; and epoxy resins having a silicone skeleton such as 1,3-bis(3-glycidoxypropyl)-1,1,3,3-tetramethyldisiloxane.

[0031] Also, 2-ethylhexyl glycidyl ether, cyclohexanedimethanol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene glycol diglycidyl ether, hydrogenated bisphenol A type epoxy resin, silicone modified epoxy resin, (poly)ethylene glycol diglycidyl ether, (poly)propylene glycol diglycidyl ether, butanediol diglycidyl ether, trimethylolpropane diglycidyl ether, poly(ethylene glycol) diglycidyl ether, Tramethylene ether glycol diglycidyl ether, glycerin diglycidyl ether, neopentyl glycol diglycidyl ether, cyclohexane type diglycidyl ether, dicyclopentadiene type diglycidyl ether, trimethylolpropane triglycidyl ether, glycerin triglycidyl ether, vinyl(3,4-cyclohexene) dioxide, 2-(3,4-epoxycyclohexyl)-5,1-spiro-(3,4-epoxycyclohexyl)-m-dioxane, tetraglycidyl bis(aminomethyl) Glycidyl amine type epoxy resins such as 1,3-diglycidyl-5-methyl-5-ethylhydantoin type epoxy resins, 1,3-bis(3-glycidoxypropyl)-1,1,3,3-tetramethyldisiloxane type epoxy resins, phenyl glycidyl ether, cresyl glycidyl ether, p-s-butylphenyl glycidyl ether, styrene oxide, p-tert-butylphenyl glycidyl ether, o-phenylphenol glycidyl ether, p-phenylphenol glycidyl ether aliphatic epoxy resins and alicyclic epoxy resins which can also be used as reactive diluents such as N-glycidyl phthalimide, n-butyl glycidyl ether, 2-ethylhexyl glycidyl ether, α-pinene oxide, allyl glycidyl ether, 1-vinyl-3,4-epoxycyclohexane, 1,2-epoxy-4-(2-methyloxiranyl)-1-methylcyclohexane, 1,3-bis(3-glycidoxypropyl)-1,1,3,3-tetramethyldisiloxane, and neodecanoic acid glycidyl ester.

[0032] The epoxy resin (A) may be solid or liquid at room temperature. By including an epoxy resin that is liquid at room temperature as the epoxy resin (A), the generated stress can be moderately alleviated, which tends to reduce warpage in the epoxy resin composition of this embodiment. Furthermore, when made into a film-type adhesive, it is possible to impart moderate tackiness, adhesion, and flexibility, which is preferable. Examples of such liquid epoxy resins include, but are not limited to, liquid epoxy resins having a bisphenol A structure, a bisphenol F structure, a bisphenol AF structure, a naphthalene structure, a glycidyl ester structure, a glycidyl amine structure, a phenol novolac structure, a cyclohexane structure, a cyclohexanedimethanol structure, or a butadiene structure, and alicyclic liquid epoxy resins having an ester skeleton are more preferable.

[0033] Specific examples of the liquid epoxy resin include those manufactured by DIC Corporation under the trade names of EXA850CRP (BisA type epoxy resin), EXA830CRP (BisF type epoxy resin), HP4032, HP4032D, and HP4032SS (naphthalene type epoxy resin); those manufactured by Mitsubishi Chemical Corporation under the trade names of jER828US, jER828EL, and jER825 (bisphenol A type epoxy resin), jER807, and jER1750 (bisphenol F type epoxy resin), and jER152 (phenol novolac type epoxy resin), jER630, and jER630LSD (glycidylamine type epoxy resin); and those manufactured by Nippon Steel Chemical & Material Co., Ltd. under the trade name of ZX1059 ( Examples of epoxy resins include those manufactured by Nagase ChemteX under the trade name of EX-721 (glycidyl ester epoxy resin), those manufactured by Daicel under the trade name of CELLOXIDE 2021P (alicyclic epoxy resin having an ester skeleton), those manufactured by Epolead PB-3600 (epoxy resin having a butadiene structure), those manufactured by Nippon Soda under the trade names of JP-100 and JP-200 (epoxy resin having a butadiene structure), and those manufactured by Asahi Kasei under the trade name of AER9000 (epoxy resin containing a special flexible skeleton). These may be used alone or in combination of two or more.

[0034] Furthermore, the epoxy resin (A) preferably contains a solid epoxy resin, which can improve the heat resistance and strength of the cured product of the cured product layer of the epoxy resin composition of this embodiment. More preferred examples of such epoxy resins include solid epoxy resins having a biphenyl structure, a bixylenol structure, a naphthalene structure, a cresol novolac structure, a dicyclopentadiene structure, a trisphenol structure, a naphthol structure, a naphthylene ether structure, an anthracene structure, a bisphenol A structure, a bisphenol AF structure, a tetraphenylethane structure, a bisphenolacetophenone structure, and a fluorene structure.

[0035] Specific examples of solid epoxy resins include those manufactured by DIC Corporation under the trade names: HP-4700, HP-4710 (naphthalene-type tetrafunctional epoxy resins), N-690, N-695 (cresol novolac-type epoxy resins), HP-7200, HP-7200H, HP-7200HH (dicyclopentadiene-type epoxy resins), HP-6000, HP-6000L, EXA-7311, EXA-7312, EXA-7313, EXA-7314, EXA-7315, EXA-7316, EXA-7317, EXA-7318, EXA-7319 ... A-7311-G3, EXA-7311-G4, EXA-7311-G4S (naphthylene ether type epoxy resin), Nippon Kayaku Co., Ltd. product names: EPPN-502H (trisphenol type epoxy resin), NC3000, NC3000H, NC3000L, NC3100 (biphenyl type epoxy resin), NC-7000L (naphthol novolac type epoxy resin), Nippon Kayaku Co., Ltd. product names: Examples of suitable epoxy resins include those manufactured by Tetsuo Sumikin Chemical Co., Ltd. under the trade names ESN475V and ESN485 (naphthol-type epoxy resins), those manufactured by Mitsubishi Chemical Corporation under the trade names YX4000, YX4000H, YX4000HS, and YL6121 (biphenyl-type epoxy resins), YX4000HK (bixylenol-type epoxy resins), YX8800 (anthracene-type epoxy resins), YX7700 (xylene structure-containing novolac-type epoxy resins), YL7760 (bisphenol AF-type epoxy resins), YL7800 (fluorene-type epoxy resins), jER1010 (bisphenol A-type solid epoxy resins), and jER1031S (tetraphenylethane-type epoxy resins), and those manufactured by Osaka Gas Chemicals Co., Ltd. under the trade names OGSOL PG-100 and CG-500 (fluorene-type epoxy resins). These may be used alone or in combination of two or more.

[0036] As the epoxy resin (A), it is preferable to use a liquid epoxy resin and a solid epoxy resin in combination, from the viewpoint of achieving a balanced combination of the above-mentioned effects. When a liquid epoxy resin and a solid epoxy resin are used in combination, the mass ratio thereof (liquid epoxy resin:solid epoxy resin) is not particularly limited, but is preferably in the range of 1:0.1 to 1:6. By setting the mass ratio of the liquid epoxy resin to the solid epoxy resin in this range, the following effects can be achieved: (i) improved tackiness and adhesion when used in the form of a film-type adhesive; (ii) sufficient flexibility and improved handleability when used in the form of a film-type adhesive; and (iii) a cured product with sufficient breaking strength can be obtained, thereby improving the reliability of printed wiring boards, semiconductor chip packages, and electronic devices using them. From the viewpoint of the effects (i) to (iii), the mass ratio of the liquid epoxy resin to the solid epoxy resin (liquid epoxy resin:solid epoxy resin) is more preferably in the range of 1:0.3 to 1:5, and even more preferably in the range of 1:0.6 to 1:4.

[0037] The epoxy resin (A) preferably has an epoxy equivalent of 50 g / eq. to 5000 g / eq., more preferably 50 g / eq. to 3000 g / eq., even more preferably 80 g / eq. to 2000 g / eq., even more preferably 100 g / eq. to 1000 g / eq., and even more preferably 120 to 900 g / eq. When the epoxy equivalent is within the above range, the crosslink density of the cured product of the epoxy resin composition of this embodiment tends to be sufficient, and a cured product layer with excellent breaking strength is obtained. The epoxy equivalent is the mass of a resin containing one equivalent of epoxy groups. The epoxy equivalent can be measured in accordance with JIS K7236.

[0038] From the viewpoint of obtaining an epoxy resin composition having excellent electrical properties and an excellent balance between curability and storage stability, the total chlorine content of the epoxy resin (A) is preferably 2500 ppm or less, more preferably 2000 ppm or less, even more preferably 1500 ppm or less, and even more preferably 900 ppm or less. Also, from the viewpoint of preventing excessive reduction, the total chlorine content of the epoxy resin (A) is preferably 0.01 ppm or more, more preferably 0.02 ppm or more, even more preferably 0.05 ppm or more, still more preferably 0.1 ppm or more, still more preferably 0.2 ppm or more, and particularly preferably 0.5 ppm or more.

[0039] Here, the total chlorine content refers to the total amount of organic chlorine and inorganic chlorine contained in the epoxy resin (A), and is a value based on the mass of the epoxy resin (A). The total chlorine content of the epoxy resin (A) is measured by the following method. The epoxy resin (A) is repeatedly washed with xylene and filtered until no epoxy resin remains in the xylene washing solution. The filtrate is then distilled under reduced pressure at 100°C or less to obtain the epoxy resin. 1 to 10 g of the obtained epoxy resin sample is precisely weighed to a titer of 3 to 7 mL, dissolved in 25 mL of ethylene glycol monobutyl ether, and 25 mL of 1 N KOH propylene glycol solution is added to the sample, followed by boiling for 20 minutes. The total chlorine content is then calculated from the titer obtained using an aqueous silver nitrate solution.

[0040] The content of the epoxy resin (A) in the epoxy resin composition of this embodiment can be appropriately set depending on the desired performance and is not particularly limited, but from the viewpoint of curability, it is preferably 5% by mass or more, more preferably 7.5% by mass or more, even more preferably 10% by mass or more, still more preferably 12% by mass or more, and even more preferably 14% by mass or more, of all non-volatile components excluding solvents. Also, from the viewpoint of handleability of the epoxy resin composition of this embodiment and a film-type adhesive using the epoxy resin composition of this embodiment, it is preferably 80% by mass or less, more preferably 70% by mass or less, even more preferably 60% by mass or less, still more preferably 55% by mass or less, and even more preferably 50% by mass or less, of all non-volatile components.

[0041] (Component (B): Specific Curing Agent) The epoxy resin composition of the present embodiment contains, as the specific curing agent, at least one curing agent selected from the group consisting of a triazine skeleton-containing phenolic curing agent, an active ester curing agent, and a cyanate ester curing agent (hereinafter, may be referred to as curing agent (B) or component (B)).

[0042] A triazine skeleton-containing phenolic curing agent functions as a curing agent for epoxy resins and has both a triazine skeleton and a structure derived from a phenolic compound in a single molecule. It is generally produced by condensing a phenolic compound with a compound having a triazine ring, such as melamine or benzoguanamine, and formaldehyde. By including the triazine skeleton-containing phenolic curing agent as component (B) in the epoxy resin composition of this embodiment, the linear expansion coefficient can be kept low due to the triazine skeleton, thereby reducing warpage and tending to improve heat resistance, strength, and adhesion to substrates. The nitrogen content of the triazine skeleton-containing phenolic curing agent is preferably 2% by mass or more, more preferably 4% by mass or more, even more preferably 5% by mass or more, even more preferably 6% by mass or more, and even more preferably 7% by mass or more, from the viewpoint of further improving the heat resistance, strength, and adhesion to substrates of the epoxy resin composition of this embodiment. On the other hand, from the viewpoint of maintaining the storage stability of the epoxy resin composition of this embodiment and the crosslink density of the cured product within an appropriate range, the nitrogen content is preferably 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less, even more preferably 25% by mass or less, and even more preferably 20% by mass or less. Furthermore, from the viewpoint of further increasing the crosslink density, the triazine skeleton-containing phenolic curing agent preferably contains a phenol novolac structure. Examples of triazine skeleton-containing phenolic curing agents containing a phenol novolac structure include, but are not limited to, LA3018, LA3018-50P, LA7052, LA7054, and LA1356, both of which are trade names manufactured by DIC Corporation.

[0043] An active ester curing agent functions as a curing agent for epoxy resins and has an active ester in its molecule. By including an active ester curing agent as component (B) in the epoxy resin composition of this embodiment, the reaction between the active ester and the epoxy group does not produce hydroxyl groups, which are a factor in increasing the dielectric loss tangent in the epoxy resin composition, and therefore the dielectric loss tangent tends to be lower. The active ester curing agent is not particularly limited, but from the viewpoint of ensuring crosslink density, a compound having two or more active ester groups in one molecule is preferred. Furthermore, from the viewpoint of the heat resistance of the epoxy resin composition of this embodiment, an active ester compound obtained by reacting a carboxylic acid compound and / or a thiocarboxylic acid compound with a hydroxy compound and / or a thiol compound is more preferred, and an active ester compound obtained by reacting a carboxylic acid compound with one or more compounds selected from a phenol compound, a naphthol compound, and a thiol compound is even more preferred. Furthermore, an aromatic compound having two or more active ester groups in one molecule obtained by reacting a carboxylic acid compound with an aromatic compound having a phenolic hydroxyl group is even more preferred. And, an aromatic compound obtained by reacting a compound having at least two or more carboxylic acids in one molecule with an aromatic compound having a phenolic hydroxyl group, and having two or more active ester groups in one molecule of the aromatic compound, is even more preferred. Furthermore, the active ester curing agent may be linear or multi-branched. Furthermore, if the compound having at least two or more carboxylic acids in one molecule is a compound containing an aliphatic chain, it tends to be able to improve compatibility with epoxy resins, and if it is a compound having an aromatic ring, it tends to be able to improve heat resistance.

[0044] Examples of the carboxylic acid compound used to prepare the active ester curing agent include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. In particular, from the viewpoint of the heat resistance of the epoxy resin composition of this embodiment, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, and terephthalic acid are preferred, and isophthalic acid and terephthalic acid are more preferred. Examples of the thiocarboxylic acid compound used to prepare the active ester curing agent include, but are not limited to, thioacetic acid and thiobenzoic acid. Examples of the phenol compound or naphthol compound used in preparing the active ester curing agent include, but are not limited to, hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalene, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucinol, benzenetriol, dicyclopentadienyl diphenol, and phenol novolak.Among these, from the viewpoints of the heat resistance of the epoxy resin composition of the present embodiment and solubility in epoxy resins and solvents, bisphenol A, bisphenol F, bisphenol S, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadienyldiphenol, and phenol novolak are preferred, and catechol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadienyldiphenol, and phenol novolak are preferred.

[0033] Examples of the thiol compound used in preparing the active ester curing agent include, but are not limited to, benzenedithiol, triazinedithiol, and the like.

[0045] The active ester compound that is the active ester-based curing agent may be the active ester compounds disclosed in JP-A-2004-277460 and JP-A-2013-40270, or commercially available active ester compounds may also be used. Examples of commercially available active ester compounds include those manufactured by DIC Corporation under the trade names EXB9451, EXB9460, EXB9460S, and HPC-8000-65T (active ester compounds containing a dicyclopentadiene-type diphenol structure), EXB9416-70BK (active ester compound containing a naphthalene structure), and EXB9050L-62M (phosphorus atom-containing active ester compound), and those manufactured by Mitsubishi Chemical Corporation under the trade names DC808 (active ester compound containing an acetylated product of phenol novolac), and YLH1026 (active ester compound containing a benzoylated product of phenol novolac).

[0046] The cyanate ester curing agent functions as a curing agent for epoxy resins and has a cyanate group in the molecule. The cyanate ester curing agent contained in the epoxy resin composition of this embodiment reacts with the epoxy group to form an oxazoline ring or an oxazolidinone ring, imparting flexibility to the epoxy resin composition. Furthermore, the trimerization of the cyanate group results in the formation of a triazine skeleton, which tends to reduce warpage and improve heat resistance in particular. Furthermore, the dielectric loss tangent tends to be kept low because hydroxyl groups are less likely to be generated during the reaction.

[0047] Examples of cyanate ester curing agents include, but are not limited to, novolac-type (phenol novolac type, alkylphenol novolac type, etc.) cyanate ester resins, dicyclopentadiene-type cyanate ester resins, bisphenol-type (bisphenol A type, bisphenol F type, bisphenol S type, etc.) cyanate ester resins, and prepolymers of these that are partially converted to triazine. Specific examples of cyanate ester resins include bifunctional cyanate resins such as bisphenol A dicyanate, polyphenol cyanate (oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanate phenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanate phenyl-1-(methylethylidene))benzene, bis(4-cyanate phenyl)thioether, and bis(4-cyanate phenyl)ether; polyfunctional cyanate resins derived from phenol novolac, cresol novolac, and dicyclopentadiene structure-containing phenolic resins; and prepolymers in which these cyanate resins are partially converted to triazine. These may be used alone or in combination of two or more. Commercially available cyanate ester resins include, for example, CYTESTER (registered trademark) TA (bisphenol A-type cyanate ester resin) manufactured by Mitsubishi Gas Chemical Company, Inc.

[0048] The above-mentioned triazine skeleton-containing phenolic curing agent, active ester curing agent, and cyanate ester curing agent may be used alone, but from the viewpoint of ensuring adhesion and bonding properties while keeping the dielectric tangent and warpage of the epoxy resin composition of the present embodiment small, it is preferable to use a combination of two or more of them, and it is more preferable to combine an active ester curing agent with a triazine skeleton-containing phenolic curing agent, or a cyanate ester curing agent with a triazine skeleton-containing phenolic curing agent.

[0049] As described above, the mass ratio of the curing agents when two types of component (B) are combined is not particularly limited, and a person skilled in the art would be able to appropriately set the mass ratio depending on the desired physical properties. However, when an active ester curing agent and a triazine skeleton-containing phenolic curing agent are combined, for example, from the viewpoint of achieving good adhesion and bondability while keeping the dielectric tangent and warpage of the epoxy resin composition of this embodiment small, the mass ratio of the active ester curing agent to the triazine skeleton-containing phenolic curing agent, in terms of the mass ratio of the non-volatile components excluding the solvent, is preferably 1:0.05 to 1:1.5, more preferably 1:0.05 to 1:1, even more preferably 1:0.07 to 1:0.8, and even more preferably 1:0.1 to 1:0.6. Furthermore, for example, when a cyanate ester curing agent and a triazine skeleton-containing phenolic curing agent are combined, from the same viewpoint as above, the mass ratio of the cyanate ester curing agent to the non-volatile components excluding the solvent is preferably 1:0.05 to 1:2.0, more preferably 1:0.1 to 1:1.5, even more preferably 1:0.2 to 1:1.2, and still more preferably 1:0.3 to 1:1, where the mass ratio of the cyanate ester curing agent is 1.

[0050] The content of component (B) in the epoxy resin composition of this embodiment can be appropriately set depending on the desired performance and is not particularly limited. However, if the number of epoxy groups in epoxy resin (A) is 1, from the viewpoint of maintaining an appropriate crosslink density between components (A) and (B) and preventing residual unreacted functional groups, the number of reactive groups in component (B) is preferably 0.1 to 3, more preferably 0.15 to 2.5, even more preferably 0.2 to 2, even more preferably 0.3 to 1.8, even more preferably 0.35 to 1.5, and particularly preferably 0.5 to 1.2. Here, the "number of epoxy groups" refers to the total value obtained by dividing the mass of each epoxy resin present in the epoxy resin composition by the epoxy equivalent weight for all epoxy resins. Furthermore, the term "reactive group" refers to a functional group capable of reacting with an epoxy group, and refers to the total value obtained by dividing the mass of the nonvolatile components of the triazine skeleton-containing phenolic curing agent, active ester curing agent, and cyanate ester curing agent present in the epoxy resin composition by the reactive group equivalent weight.

[0051] (Component (C): Compound Represented by Formula (1) or (2) Below) The epoxy resin composition of the present embodiment contains a compound represented by Formula (1) below and / or a compound represented by Formula (2) below (hereinafter, may be referred to as compound (C) or component (C)).

[0052]

[0053]

[0054] In formulas (1) and (2), R １ , R ２ are each independently any one selected from the group consisting of a hydrogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, a halogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, and a cycloalkyl group having 6 to 20 carbon atoms which may have a substituent. １ , R ２ may be the same or different, R １ , R ２ may be bonded to form a non-aromatic fused ring. X is any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aralkyl group having 7 to 20 carbon atoms which may have a substituent, and a heteroarylalkyl group having 4 to 20 carbon atoms which may have a substituent. Y and Z are any one selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 20 carbon atoms which may have a substituent, an aryloxy group having 6 to 20 carbon atoms which may have a substituent, and an acyl group having 1 to 20 carbon atoms which may have a substituent. Y and Z may be the same or different, and two or more Ys and two or more Zs may be bonded to form a monocyclic or fused ring. m and n are integers of 1 to 4.

[0055] R in the above general formula (1) １and R ２ As described above, each of R is independently one selected from the group consisting of a hydrogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, a halogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, and a cycloalkyl group having 6 to 20 carbon atoms which may have a substituent, or R １ , R ２ are on the same fused ring without aromaticity, and R １ , R ２ may be the same or different. The alkyl group having 1 to 20 carbon atoms may be linear or branched, and the number of carbon atoms in the alkyl group is preferably 1 to 18, more preferably 1 to 15, and even more preferably 1 to 10. Examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, an isopropyl group, a butyl group, an isobutyl group, a hexyl group, an octyl group, and a 2-ethylhexyl group. The number of carbon atoms in the cycloalkyl group having 6 to 20 carbon atoms is preferably 6 to 18, and more preferably 6 to 15. Examples of the cycloalkyl group having 6 to 20 carbon atoms include a cyclohexyl group, a cycloheptane group, and a cyclooctane group. The R １ , R ２ Specific examples of the structure in which R is on the same condensed ring without aromaticity include cyclopentane, cyclohexane, dicyclopentadiene, etc. １ , R ２ The structure on the same fused ring that does not have aromaticity may have a substituent, and examples of the substituent include a halogen atom, a hydroxyl group, an alkoxy group, and a nitro group, and preferably a hydroxyl group or an alkoxy group.

[0056] X in the formulas (1) and (2) is any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aralkyl group having 7 to 20 carbon atoms which may have a substituent, and a heteroarylalkyl group having 4 to 20 carbon atoms which may have a substituent.

[0057] The alkyl group having 1 to 20 carbon atoms represented by X may be linear or branched, and the number of carbon atoms in the alkyl group is preferably 1 to 18, more preferably 1 to 15. Examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, an isopropyl group, a butyl group, an isobutyl group, a hexyl group, and an octyl group.

[0058] The alkenyl group having 2 to 20 carbon atoms represented by X may be linear or branched, and the number of carbon atoms in the alkenyl group is preferably 2 to 18, and more preferably 2 to 15. Examples of the alkenyl group having 2 to 20 carbon atoms include a vinyl group, an aryl group, a 1-propenyl group, an isopropenyl group, a 2-butenyl group, a 3-butenyl group, a 2-pentenyl group, and a 2-hexenyl group.

[0059] The aralkyl group having 7 to 20 carbon atoms represented by X may be linear or branched, and the number of carbon atoms in the aralkyl group is preferably 7 to 18, more preferably 7 to 15. Examples of the aralkyl group having 7 to 20 carbon atoms include a benzyl group, a phenethyl group, and a naphthylmethyl group.

[0060] The heteroarylalkyl group having 4 to 20 carbon atoms represented by X may be linear or branched, and the number of carbon atoms in the heteroarylalkyl group is preferably 4 to 18, and more preferably 4 to 15. Examples of the heteroarylalkyl group having 4 to 20 carbon atoms include a triazinylmethyl group, a triazinylethyl group, a 2-pyridylmethyl group, a 2-pyridylethyl group, a 3-pyridylmethyl group, a 3-pyridylethyl group, a 4-pyridylmethyl group, and a 4-pyridylethyl group.

[0061] The alkyl group, alkenyl group, aralkyl group, or heteroarylalkyl group may each have a substituent. Examples of the substituent include a halogen atom, a cyano group, a nitro group, a hydroxyl group, an alkoxy group, an amino group, an ester group, an arylsulfonyl group, an alkylsulfonyl group, and a phenyl group, and preferred are a cyano group, an alkoxy group, an amino group, an ester group, and a phenyl group.

[0062] Y and Z in the general formulas (1) and (2) each represent one selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 20 carbon atoms which may have a substituent, an aryloxy group having 6 to 20 carbon atoms which may have a substituent, and an acyl group having 1 to 20 carbon atoms which may have a substituent, or a structure in which two or more Ys and two or more Zs are bonded to form a monocycle or a condensed ring, and m and n are integers of 1 to 4.

[0063] The alkyl group having 1 to 20 carbon atoms represented by Y and Z may be linear or branched, and the number of carbon atoms in the alkyl group is preferably 1 to 18, more preferably 1 to 15. Examples of the alkyl group having 1 to 20 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a hexyl group, an octyl group, a 2-ethylhexyl group, a decyl group, and an undecyl group.

[0064] The alkoxy group having 1 to 20 carbon atoms represented by Y and Z may be linear or branched, and preferably has 1 to 18 carbon atoms, more preferably 1 to 15 carbon atoms. Examples of the alkoxy group having 1 to 20 carbon atoms include a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, a hexyloxy group, and a 2-ethylhexyloxy group.

[0065] The alkenyl group having 2 to 20 carbon atoms represented by Y and Z may be linear or branched, and the number of carbon atoms in the alkenyl group is preferably 2 to 18, more preferably 2 to 15. Examples of the alkenyl group having 2 to 20 carbon atoms include a vinyl group, an aryl group, a 1-propenyl group, an isopropenyl group, a 2-butenyl group, a 3-butenyl group, a 2-pentenyl group, and a 2-hexenyl group.

[0066] The number of carbon atoms in the aryl group having 6 to 20 carbon atoms represented by Y and Z is preferably 6 to 18, more preferably 6 to 15. Examples of the aryl group having 6 to 20 carbon atoms include a phenyl group, a naphthyl group, an anthracenyl group, and a biphenyl group.

[0067] Examples of the structure in which two or more Y's or two or more Z's are bonded to form a single ring or a condensed ring include a naphthyl group and an anthracenyl group.

[0068] The number of carbon atoms in the acyl group having 1 to 20 carbon atoms represented by Y and Z is preferably 1 to 18, more preferably 1 to 15. Examples of the acyl group having 1 to 20 carbon atoms include an acetyl group, a benzoyl group, and a pivaloyl group.

[0069] The alkyl group, alkoxy group, alkenyl group, aryl group, aryloxy group, and acyl group may have a substituent. Examples of the substituent include an alkyl group, a halogen atom, a hydroxyl group, a carboxy group, an alkoxy group, a nitro group, an ester group, and a phenyl group, and preferred are an alkyl group, a hydroxyl group, a carboxy group, and an alkoxy group.

[0070] Y may be substituted at any of the ortho, meta, or para positions of the phenyl group which is the substituent at the 2-position of the imidazole; however, when Y has a substituent, it is preferably substituted at a position other than the ortho position, and more preferably at least the meta position, and more preferably the meta position is substituted with a hydroxyl group or an alkoxy group having 1 to 20 carbon atoms which may have a substituent.

[0071] Among the above, Y and Z in general formulas (1) and (2) are more preferably any one selected from the group consisting of a hydrogen atom, a hydroxyl group, a carboxy group, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent, an alkoxy group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent, an aryl group having 6 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent, an aryloxy group having 6 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent, and an acyl group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent. When Y and Z are hydrogen atoms, the dielectric loss tangent of the cured product obtained using the epoxy resin composition of this embodiment can be further reduced. Furthermore, when Y and Z are a hydroxyl group, a carboxyl group, an alkoxy group having 1 to 20 carbon atoms and no substituent, an alkyl group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent, an alkoxy group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent, an aryl group having 6 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent, an aryloxy group having 6 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent, or an acyl group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxyl group as a substituent, the coordination bond to an adherend such as a metal is increased, and therefore the adhesion and adhesive strength tend to be improved.

[0072] Examples of the compound represented by the general formula (1) include, but are not limited to, the following imidazole compounds: 2-(2-hydroxyphenyl)imidazole, 2-(2-hydroxyphenyl)-4(5)-methylimidazole, 4(5)-ethyl-2-(2-hydroxyphenyl)imidazole, 4,5-dimethyl-2-(2-hydroxyphenyl)imidazole, 4-ethyl-(2-hydroxyphenyl)-5-methylimidazole, (2-hydroxyphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-(2-hydroxyphenyl)-5-methylimidazole, 2-(2-hydroxy-3-methylphenyl)imidazole, 2-(2-hydroxy-3-methylphenyl)-4(5)-methylimidazole, 4(5)-ethyl 2-(2-hydroxy-3-methylphenyl)imidazole, 4,5-dimethyl-2-(2-hydroxy-3-methylphenyl)imidazole, 4-ethyl-(2-hydroxy-3-methylphenyl)-5-methylimidazole, (2-hydroxy-3-methylphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-(2-hydroxy-3-methylphenyl)-5-methylimidazole, 2-(2-hydroxy-4-methylphenyl)imidazole, 2-(2-hydroxy-4-methylphenyl)-4(5)-methylimidazole, 4(5)-ethyl-2-(2-hydroxy-4-methylphenyl)imidazole.

[0073] Also, 4,5-dimethyl-2-(2-hydroxy-4-methylphenyl)imidazole, 4-ethyl-(2-hydroxy-4-methylphenyl)-5-methylimidazole, (2-hydroxy-4-methylphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-(2-hydroxy-4-methylphenyl)-5-methylimidazole, 2-(2-hydroxy-5-methylphenyl)imidazole, 2-(2-hydroxy-5-methylphenyl)-4(5)-methylimidazole, 4(5)-ethyl-2-(2-hydroxy-5-methylphenyl)imidazole, 4,5- Examples of the hydroxyphenylimidazole include dimethyl-2-(2-hydroxy-5-methylphenyl)imidazole, 4-ethyl-(2-hydroxy-5-methylphenyl)-5-methylimidazole, (2-hydroxy-5-methylphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-(2-hydroxy-5-methylphenyl)-5-methylimidazole, 2-(3-t-butyl-2-hydroxyphenyl)imidazole, 2-(3-t-butyl-2-hydroxyphenyl)-4(5)-methylimidazole, and 2-(3-t-butyl-2-hydroxyphenyl)-4(5)-ethylimidazole.

[0074] Further, 2-(3-t-butyl-2-hydroxyphenyl)-4,5-dimethylimidazole, 2-(3-t-butyl-2-hydroxyphenyl)-4-ethyl-5-methylimidazole, 2-(3-t-butyl-2-hydroxyphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-2-(3-t-butyl-2-hydroxyphenyl)-5-methylimidazole, 2-(4-fluoro-2-hydroxyphenyl)imidazole, 2-(4-fluoro-2-hydroxyphenyl)-4(5)-methylimidazole, 2-(4-fluoro-2-hydroxyphenyl)-4(5)-ethylimidazo imidazole, 2-(4-fluoro-2-hydroxyphenyl)-4,5-dimethylimidazole, 4-ethyl-2-(4-fluoro-2-hydroxyphenyl)-5-methylimidazole, 2-(4-fluoro-2-hydroxyphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-2-(4-fluoro-2-hydroxyphenyl)-5-methylimidazole, 2-(4-chloro-2-hydroxyphenyl)imidazole, 2-(4-chloro-2-hydroxyphenyl)-4(5)-methylimidazole, and 2-(4-chloro-2-hydroxyphenyl)-4(5)-ethylimidazole.

[0075] Further, 2-(4-chloro-2-hydroxyphenyl)-4,5-dimethylimidazole, 2-(4-chloro-2-hydroxyphenyl)-4-ethyl-5-methylimidazole, 2-(4-chloro-2-hydroxyphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-2-(4-chloro-2-hydroxyphenyl)-5-methylimidazole, 2-(4-bromo-2-hydroxyphenyl)imidazole, 2-(4-bromo-2-hydroxyphenyl)-4(5)-methylimidazole 2-(4-bromo-2-hydroxyphenyl)-4(5)-ethylimidazole, 2-(4-bromo-2-hydroxyphenyl)-4,5-dimethylimidazole, 2-(4-bromo-2-hydroxyphenyl)-4-ethyl-5-methylimidazole, 2-(4-bromo-2-hydroxyphenyl)-4-isopropyl-5-methylimidazole, 2-(4-bromo-2-hydroxyphenyl)-4-butyl-5-methylimidazole, and 2-(2,3-dihydroxyphenyl)imidazole.

[0076] Furthermore, 2-(2,3-dihydroxyphenyl)-4(5)-methylimidazole, 2-(2,3-dihydroxyphenyl)-4(5)-ethylimidazole, 2-(2,3-dihydroxyphenyl)-4,5-dimethylimidazole, 2-(2,3-dihydroxyphenyl)-4(5)-phenylimidazole, 2-(2,3-dihydroxyphenyl)-4,5-diphenylimidazole, 2-(2,5-dihydroxyphenyl)imidazole, 2-(2,5-dihydroxyphenyl)-4(5)-methylimidazole, 2-(2,5-dihydroxyphenyl)-4(5)-ethylimidazole, 2-(2,5-dihydroxyphenyl)-4,5-dimethylimidazole, 2-(2,5-dihydroxyphenyl)-4(5)-phenylimidazole, 2-(2,5-dihydroxyphenyl)-4(5)-phenylimidazole, phenyl)-4,5-diphenylimidazole, 2-(2-hydroxy-4-methoxyphenyl)imidazole, 2-(2-hydroxy-4-methoxyphenyl)-4(5)-methylimidazole, 4(5)-ethyl-2-(2-hydroxy-4-methoxyphenyl)imidazole, 4,5-dimethyl-2-(2-hydroxy-4-methoxyphenyl)imidazole, 2-(2-hydroxy-4-methoxyphenyl)-4(5)-phenylimidazole, 4,5-diphenyl-2-(2-hydroxy-4-methoxyphenyl)imidazole, 2-(2-hydroxy-3-methoxyphenyl)imidazole, 2-(2-hydroxy-3-methoxyphenyl)-4(5)-methylimidazole, 4(5)-ethyl-2-(2-hydroxy-3-methoxyphenyl)imidazole.

[0077] Also, 4,5-dimethyl-2-(2-hydroxy-3-methoxyphenyl)imidazole, 2-(2-hydroxy-3-methoxyphenyl)-4(5)-phenylimidazole, 4,5-diphenyl-2-(2-hydroxy-3-methoxyphenyl)imidazole, 2-(2-hydroxy-5-methoxyphenyl)imidazole, 2-(2-hydroxy-5-methoxyphenyl)-4(5)-methylimidazole, 4(5)-ethyl-2-(2-hydroxy-5-methoxyphenyl)imidazole, 4,5-dimethyl-2-(2-hydroxy-5-methoxyphenyl)imidazole, 2-(2-hydroxy-5-methoxyphenyl)-4(5)-phenylimidazole, 4,5-diphenyl-2-(2-hydroxy-5-methoxyphenyl)imidazole, 2-(2-hydroxy-6-methoxyphenyl)imidazole, 2-(2- hydroxy-6-methoxyphenyl)-4(5)-methylimidazole, 4(5)-ethyl-2-(2-hydroxy-6-methoxyphenyl)imidazole, 4,5-dimethyl-2-(2-hydroxy-6-methoxyphenyl)imidazole, 2-(2-hydroxy-6-methoxyphenyl)-4(5)-phenylimidazole, 4,5-diphenyl-2-(2-hydroxy-6-methoxyphenyl)imidazole, 2-(3-ethoxy-2-hydroxyphenyl)imidazole, 2-(3-ethoxy-2-hydroxyphenyl)-4(5)-methylimidazole, 2-(3-ethoxy-2-hydroxyphenyl)-4(5)-ethylimidazole, 4,5-dimethyl-2-(3-ethoxy-2-hydroxyphenyl)imidazole, 2-(3-ethoxy-2-hydroxyphenyl)-4(5)-phenylimidazole.

[0078] Further, 4,5-diphenyl-2-(3-ethoxy-2-hydroxyphenyl)imidazole, 2-(5-ethoxy-2-hydroxyphenyl)imidazole, 2-(5-ethoxy-2-hydroxyphenyl)imidazole, 2-(5-ethoxy-2-hydroxyphenyl)-4(5)-methylimidazole, 2-(5-ethoxy-2-hydroxyphenyl)-4(5)-ethylimidazole, 4,5-dimethyl-2-(5-ethoxy-2-hydroxyphenyl)imidazole, 2-(5-ethoxy-2-hydroxyphenyl)-4(5)-phenylimidazole, 4,5-diphenyl-2-(5-ethoxy-2-hydroxyphenyl)imidazole, 2-(4-allyl-2-hydroxyphenyl)imidazole 2-(4-allyl-2-hydroxy-3-methoxyphenyl)imidazole, 2-(4-allyl-2-hydroxy-3-methoxyphenyl)-4(5)-methylimidazole, 2-(4-allyl-2-hydroxy-3-methoxyphenyl)-4(5)-ethylimidazole, 2-(4-allyl-2-hydroxy-3-methoxyphenyl)-4,5-dimethylimidazole, 2-(4-allyl-2-hydroxy-3-methoxyphenyl)-4(5)-phenylimidazole, 2-(4-allyl-2-hydroxy-3-methoxyphenyl)-4,5-diphenylimidazole, and 2-(4,6-dimethoxy-2-hydroxyphenyl)imidazole.

[0079] Further, 2-(4,6-dimethoxy-2-hydroxyphenyl)-4(5)-methylimidazole, 2-(4,6-dimethoxy-2-hydroxyphenyl)-4(5)-ethylimidazole, 2-(4,6-dimethoxy-2-hydroxyphenyl)-4,5-dimethylimidazole, 2-(4,6-dimethoxy-2-hydroxyphenyl)-4(5)-phenylimidazole, 2-(4,6-dimethoxy-2-hydroxyphenyl)-4,5-diphenylimidazole, 2-(2-fluoro-5-hydroxyphenyl)imidazole, 2-(2-fluoro-5-hydroxyphenyl)-4(5)-methylimidazole, Examples of the fluoroisopropyl methylimidazole include imidazole, 2-(2-fluoro-5-hydroxyphenyl)-4(5)-ethylimidazole, 2-(2-fluoro-5-hydroxyphenyl)-4,5-dimethylimidazole, 2-(2-fluoro-5-hydroxyphenyl)-4(5)-phenylimidazole, 2-(2-fluoro-5-hydroxyphenyl)-4,5-diphenylimidazole, 2-(5-fluoro-2-hydroxyphenyl)imidazole, 2-(5-fluoro-2-hydroxyphenyl)-4(5)-methylimidazole, and 2-(5-fluoro-2-hydroxyphenyl)-4(5)-ethylimidazole.

[0080] Furthermore, 2-(5-fluoro-2-hydroxyphenyl)-4,5-dimethylimidazole, 2-(5-fluoro-2-hydroxyphenyl)-4(5)-phenylimidazole, 2-(5-fluoro-2-hydroxyphenyl)-4,5-diphenylimidazole, 2-(5-chloro-2-hydroxyphenyl)imidazole, 2-(5-chloro-2-hydroxyphenyl)-4(5)-methylimidazole, 2-(5-chloro-2-hydroxyphenyl)-4(5)-ethylimidazole, 2-(5-chloro-2-hydroxyphenyl)-4,5-dimethylimidazole, 2-(5-chloro-2-hydroxyphenyl)-4(5)-phenylimidazole imidazole, 2-(5-chloro-2-hydroxyphenyl)-4,5-diphenylimidazole, 2-(5-bromo-2-hydroxyphenyl)imidazole, 2-(5-bromo-2-hydroxyphenyl)-4(5)-methylimidazole, 2-(5-bromo-2-hydroxyphenyl)-4(5)-ethylimidazole, 2-(5-bromo-2-hydroxyphenyl)-4,5-dimethylimidazole, 2-(5-bromo-2-hydroxyphenyl)-4(5)-phenylimidazole, 2-(5-bromo-2-hydroxyphenyl)-4,5-diphenylimidazole, 2-(6-fluoro-2-hydroxy-3-methoxyphenyl)imidazole.

[0081] Also, 2-(6-fluoro-2-hydroxy-3-methoxyphenyl)-4(5)-methylimidazole, 2-(6-fluoro-2-hydroxy-3-methoxyphenyl)-4(5)-ethylimidazole, 2-(6-fluoro-2-hydroxy-3-methoxyphenyl)-4,5-dimethylimidazole, 2-(6-fluoro-2-hydroxy-3-methoxyphenyl)-4(5)-phenylimidazole, 2-(6-fluoro-2-hydroxy-3-methoxyphenyl)-4,5-diphenylimidazole, 2-(1-hydroxynaphthalen-2-yl)imidazole, 2-(1-hydroxynaphthalen-2-yl)-4(5)-methylimidazole, 2-(1-hydroxynaphthalen-2-yl)-4(5)-ethylimidazole, 4 , 5-dimethyl-2-(1-hydroxynaphthalen-2-yl)imidazole, 2-(1-hydroxynaphthalen-2-yl)-4(5)-phenylimidazole, 4,5-diphenyl-2-(1-hydroxynaphthalen-2-yl)imidazole, 2-(2-hydroxynaphthalen-1-yl)imidazole, 2-(2-hydroxynaphthalen-1-yl)-4(5)-methylimidazole, 2-(2-hydroxynaphthalen-1-yl)-4(5)-ethylimidazole, 4,5-dimethyl-2-(2-hydroxynaphthalen-1-yl)imidazole, 2-(2-hydroxynaphthalen-1-yl)-4(5)-phenylimidazole, 4,5-diphenyl-2-(2-hydroxynaphthalen-1-yl)imidazole and the like.

[0082] The compound represented by the general formula (2) includes, but is not limited to, the following imidazole compounds. For example, 2-(2-hydroxyphenyl)benzimidazole, 2-(2-hydroxy-3-methylphenyl)benzimidazole, 2-(2-hydroxy-4-methylphenyl)benzimidazole, 2-(2-hydroxy-5-methylphenyl)benzimidazole, 2-(3-t-butyl-2-hydroxyphenyl)benzimidazole, 2-(4-fluoro-2-hydroxyphenyl)benzimidazole, 2-(4-chloro-2-hydroxyphenyl)benzimidazole, 2-(4-bromo-2-hydroxyphenyl)benzimidazole, 2-(2,3-dihydroxyphenyl)benzimidazole, 2-(2,5-dihydroxyphenyl)benzimidazole, 2-(2-hydroxy-4-methoxyphenyl)benzimidazole, 2-(2-hydroxy-3-methoxyphenyl)benzimidazole, 2-(2-hydroxy-5-methoxyphenyl)benzimidazole, 2 2-(2-hydroxy-6-methoxyphenyl)benzimidazole, 2-(3-ethoxy-2-hydroxyphenyl)benzimidazole, 2-(5-ethoxy-2-hydroxyphenyl)benzimidazole, 2-(4-allyl-2-hydroxy-3-methoxyphenyl)benzimidazole, 2-(4,6-dimethoxy-2-hydroxyphenyl)benzimidazole, 2-(5-fluoro-2-hydroxyphenyl)benzimidazole, 2-(5-chloro-2-hydroxyphenyl)benzimidazole, 2-(5-bromo-2-hydroxyphenyl)benzimidazole, 2-(6-fluoro-2-hydroxy-3-methoxyphenyl)benzimidazole, 2-(1-hydroxynaphthalen-2-yl)benzimidazole, 2-(2-hydroxynaphthalen-1-yl)benzimidazole, 2-(2-hydroxyphenyl)benzimidazole-6-carboxylic acid and the like.

[0083] Among these, from the viewpoint of obtaining a uniform epoxy resin composition by having excellent solubility in the epoxy resin (A) and solvents, and achieving both reduced warpage and high heat resistance of the cured product, the compound represented by the general formula (1) is preferably R １, R ２ are preferably all hydrogen atoms or have different substituents. For example, 2-(2-hydroxyphenyl)imidazole, 2-(2-hydroxyphenyl)-4(5)-methylimidazole, 4-ethyl-(2-hydroxyphenyl)-5-methylimidazole, (2-hydroxyphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-(2-hydroxyphenyl)-5-methylimidazole, and 2-(2-hydroxy-3(5)-methoxyphenyl)imidazole are more preferred, and 2-(2-hydroxyphenyl)imidazole is even more preferred. Furthermore, from the viewpoint of obtaining similar effects, the compound represented by the general formula (2) is preferably 2-(2-hydroxyphenyl)benzimidazole, 2-(2-hydroxy-3(5)-methoxyphenyl)benzimidazole, 2-(1-hydroxynaphthalen-2-yl)benzimidazole, 2-(2-hydroxynaphthalen-1-yl)benzimidazole, or 2-(2-hydroxyphenyl)benzimidazole-6-carboxylic acid, and more preferably 2-(2-hydroxyphenyl)benzimidazole or 2-(2-hydroxy-3(5)-methoxyphenyl)benzimidazole.

[0084] The epoxy resin composition of this embodiment surprisingly reduces warpage of the cured product and also imparts high heat resistance by including component (C): a compound represented by general formula (1) or (2) as a catalyst. Such an effect cannot be easily predicted from the structure of component (C). Furthermore, the inventors tested the effects of imidazole compounds with various structures in the process of arriving at the present invention, but the only compounds that were able to reduce warpage of the cured product and also impart high heat resistance were those containing component (C) of the present invention as a catalyst, demonstrating a very unique effect. Furthermore, component (C) is a component that catalytically reacts with component (A): the epoxy resin, and can achieve the above-mentioned effect simply by adding it to the epoxy resin composition. Therefore, unlike conventional warpage reduction techniques, this warpage reduction effect can be achieved without incorporating epoxy resins or polymers with flexible backbones or high concentrations of fillers, thereby significantly increasing the blending flexibility of those skilled in the art.

[0085] In the epoxy resin composition of this embodiment, the addition of the compound of component (C) to the specific curing agent (component (B)) described above not only achieves both stability and curability, but also reduces warpage and exhibits high heat resistance in the cured product. The mechanism by which this is achieved is thought to be, but is not limited to, the following: Component (C) has a structural feature in which a hydroxyphenyl group is substituted at the 2-position of the imidazole structure that reacts with epoxy groups. Regarding the compatibility of stability and curability, as described in Patent Document 2, it is believed that an intramolecular hydrogen bond is formed between the nitrogen, which is the reaction site of the imidazole, and the adjacent hydroxyphenyl group, thereby suppressing the nucleophilicity of the nitrogen on the imidazole during storage, thereby maintaining stability, but dissociating the hydrogen bond and allowing a reaction upon heating. Subsequently, various imidazole compounds were investigated to determine whether the cured product exhibited reduced warpage and high heat resistance. As a result, it was confirmed that component (C) used in the epoxy resin composition of this embodiment exhibited a significant effect. From this, it is believed that component (C), due to its structural characteristics, plays a role as a chain transfer agent, in that the adjacent hydroxyphenyl group donates a proton to the anion generated when the epoxy group reacts with imidazole to open the ring, thereby stabilizing it. Therefore, during the polymerization reaction, the rapid generation of high molecular weight compounds concentrated around the reaction site and localized viscosity increase are suppressed, and the chain extension reaction can occur throughout the system. Therefore, the viscosity increase during curing occurs slowly and uniformly, which makes it easier to relieve stress generated during curing, reducing warpage in the cured product. In addition, it is believed that the low level of unreacted epoxy groups results in a high crosslink density and high heat resistance.

[0086] Furthermore, when the compound of component (C) described above is used as a catalyst for the specific curing agent (component (B)) described above, the above-mentioned effects can be further enhanced. For example, triazine skeleton-containing phenolic curing agents and cyanate ester curing agents, due to their structure, tend to have poor storage stability even in the absence of a catalyst due to the presence of amine groups and cyanato groups that react with epoxy groups, and the degree of deterioration becomes even more pronounced when a catalyst is added. Furthermore, active ester curing agents have low reactivity with epoxy groups as they are, so it is important to add a catalyst and cure at a high temperature of 180°C or higher in order to develop physical properties. However, with general catalysts, the self-polymerization reaction of epoxy groups occurs competitively before the active esters fully react at the curing temperature, so unreacted active ester groups tend to remain. On the other hand, due to its structure, the above-mentioned component (C) can significantly improve storage stability even when a triazine skeleton-containing phenolic curing agent or a cyanate ester curing agent is used. Furthermore, even during reactions at high temperatures such as 150°C or higher or 180°C or higher, its function as a chain transfer agent suppresses the rapid self-polymerization reaction of the epoxy group alone and allows the reaction between each curing agent (B) and the epoxy group to proceed efficiently, so that unreacted functional groups are less likely to remain and the inherent heat resistance and strength of the composition tend to be fully achieved. Furthermore, because component (C) uniformly catalyzes the reaction between curing agent (B) and the epoxy group, curing proceeds without localized stress concentration, further enhancing the effect of reducing warpage of the cured product.

[0087] Considering the above mechanism, the effects of the present invention can be achieved by using a wide range of components (C) having the structural characteristics represented by general formula (1) and / or (2), including those with various functional group substitutions, in combination with curing agent (B).

[0088] Because component (C) has an aromatic ring and a hydroxyl group, it has excellent compatibility with resins having an aromatic ring and polar solvents, and can dissolve well in various epoxy resins and solvents. Solid-dispersion imidazole compounds with reduced compatibility with epoxy resins are generally known as highly stable imidazole compounds. However, these imidazole compounds have concerns about reduced curing uniformity due to their solid state. Furthermore, when a process for thinning the film by blending a solvent is performed, such as in film-type adhesives, they have problems such as reduced film-forming properties due to residual particles, inapplicability to ultra-thin films, and instability due to dissolution in some solvents, even in solid-dispersion form. Therefore, component (C) used in the epoxy resin composition of this embodiment, which can dissolve uniformly in resins and solvents while maintaining both stability and reactivity, is particularly suitable for applications that use solvents, such as film-type adhesives.

[0089] In the epoxy resin composition of this embodiment, the mass ratio of the above-mentioned components (B) and (C) is not particularly limited, but in terms of the mass ratio of non-volatile components excluding the solvent, where component (B) is taken as 100, (component (B):component (C)) is preferably 100:0.1 to 100:40, more preferably 100:0.5 to 100:30, even more preferably 100:1 to 100:20, even more preferably 100:1.5 to 100:15, even more preferably 100:1.8 to 100:12, and particularly preferably 100:2 to 100:10. By setting the mass ratio within this range, it is possible to sufficiently obtain the reaction-accelerating effect of component (B) by component (C) while preventing unnecessary self-polymerization reaction of the epoxy resin by component (C). This also ensures that the crosslink density of the resulting cured product falls within an appropriate range, which tends to result in a cured product layer that is more excellent in heat resistance and strength.

[0090] The content of component (C) in the entire epoxy resin composition of this embodiment is not particularly limited, but from the viewpoint of obtaining sufficient curability, it is preferably 0.005% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, still more preferably 0.15% by mass or more, and even more preferably 0.2% by mass or more, based on all non-volatile components excluding the solvent. From the viewpoint of maintaining an appropriate curing rate and maintaining uniformity of the cured product layer, it is preferably 10% by mass or less, more preferably 5% by mass or less, even more preferably 4% by mass or less, still more preferably 3% by mass or less, and even more preferably 2% by mass or less. However, because component (C) catalytically reacts with component (A): the epoxy resin, a person skilled in the art can determine an appropriate amount taking into consideration the materials and composition used and the desired performance.

[0091] (Component (D): Filler) The epoxy resin composition of this embodiment may further contain a filler (hereinafter, may be referred to as filler (D) or component (D)). The filler (D) is not particularly limited, and examples thereof include one or more types selected from the group consisting of inorganic fillers (inorganic fillers) and inorganic fillers pre-treated with a silane coupling agent (H) described below from the viewpoint of reducing warpage, and organic fillers from the viewpoint of improving adhesive strength and crack resistance. These may be used alone or in combination of two or more types. The shape of the filler (D) is not particularly limited, and may be, for example, amorphous, spherical, or scaly. From the viewpoint of approximating the linear expansion coefficients of the epoxy resin composition of this embodiment and the substrate to be adhered, and thereby reducing warpage, it is preferable to contain an inorganic filler.

[0092] Examples of inorganic fillers include, but are not limited to, silica, alumina, glass, cordierite, silicone oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate titanate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate; carbons such as carbon nanotubes and graphene; metals or alloys such as gold, silver, copper, nickel, aluminum, zinc, tin, lead, solder, indium, and palladium; and particles of a polymer core coated with a metal thin film. Among these, silica is preferred from the viewpoint of further reducing warpage of the cured product. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, hollow silica, etc., and from the viewpoint of improving filling properties and ease of handling of the epoxy resin composition, it is more preferable that the shape is spherical. Examples of commercially available spherical fused silica include those manufactured by Admatechs Co., Ltd. under the trade names SO-C2, SO-C1, SO-E2, and SO-E1.

[0093] The average particle size of the filler (D) is not particularly limited, but from the viewpoint of forming a cured layer using an epoxy resin composition containing component (D) and enabling the formation of fine wiring on the cured layer, it is preferably 3 μm or less, more preferably 2 μm or less, and even more preferably 1 μm or less, 0.7 μm or less, 0.5 μm or less, 0.4 μm or less, or 0.3 μm or less. On the other hand, from the viewpoint of obtaining a resin paste with an appropriate viscosity and good handleability when forming a resin paste using the epoxy resin composition, the average particle size of component (D): filler is preferably 0.01 μm or more, more preferably 0.03 μm or more, and even more preferably 0.05 μm or more, 0.07 μm or more, or 0.1 μm or more. The average particle size of the filler can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, it can be measured by creating a particle size distribution of the filler on a volume basis using a laser diffraction particle size distribution analyzer and using the median diameter as the average particle size. As the laser diffraction particle size distribution measuring device, a product name: HELOS manufactured by Sympatec or the like can be used.

[0094] When an inorganic filler is used as filler (D), the content of the inorganic filler in the epoxy resin composition of the present embodiment can be appropriately set depending on the desired performance and is not particularly limited, but is preferably 5 to 98 mass %, more preferably 10 to 95 mass %, even more preferably 15 to 90 mass %, still more preferably 20 to 88 mass %, even more preferably 25 to 85 mass %, and particularly preferably 30 to 80 mass % of all non-volatile components excluding the solvent. By setting the content within these ranges, the epoxy resin composition and film-type adhesive of the present embodiment can further exhibit the effects (i) to (iii), such as (i) maintaining an appropriate viscosity and excellent handleability, (ii) having just the right amount of resin component and inorganic filler, and therefore excellent adhesiveness, adhesion, and dimensional stability, and (iii) excellent warpage, heat resistance, and breaking strength when the resin composition is cured.

[0095] The organic filler functions as an impact absorbing agent having stress relaxation properties. By including the organic filler, the epoxy resin composition of the present embodiment can further improve adhesion to various connecting members and also tends to be able to suppress the occurrence and propagation of fillet cracks.

[0096] Examples of the organic filler include, but are not limited to, organic fine particles of acrylic resin, silicone resin, butadiene rubber, polyester, polyurethane, polyvinyl butyral, polyarylate, polymethyl methacrylate, acrylic rubber, polystyrene, acrylonitrile-butadiene rubber (NBR), styrene-butadiene rubber (SBR), silicone-modified resin, and copolymers containing these as components. From the viewpoint of improving adhesiveness, preferred examples of the organic fine particles include alkyl (meth)acrylate-butadiene-styrene copolymer, alkyl (meth)acrylate-silicone copolymer, silicone-(meth)acrylic copolymer, a composite of silicone and (meth)acrylic acid, a composite of alkyl (meth)acrylate-butadiene-styrene and silicone, and a composite of alkyl (meth)acrylate and silicone.

[0097] The organic filler may also be organic fine particles having a core-shell structure, with the core and shell layers having different compositions. Examples of core-shell organic fine particles include, but are not limited to, particles having a silicone-acrylic rubber core and an acrylic resin grafted thereto, and particles having an acrylic resin grafted to an acrylic copolymer. The low elastic modulus achieved by the inclusion of core-shell organic fine particles tends to reduce stress generated in the fillet portion and inhibit the occurrence of fillet cracks. Furthermore, if fillet cracks do occur, the contained core-shell organic fine particles act as a stress reliever, tending to inhibit the progression of the fillet cracks. A material with excellent flexibility is preferably used as the constituent material for the core layer. Examples of constituent materials for the core layer include, but are not limited to, silicone-based elastomers, butadiene-based elastomers, styrene-based elastomers, acrylic elastomers, polyolefin-based elastomers, and silicone / acrylic composite elastomers. On the other hand, the constituent material for the shell layer is preferably a material with excellent affinity for other components of the semiconductor resin encapsulant, particularly for epoxy resins. Examples of materials constituting the shell layer include, but are not limited to, acrylic resins and epoxy resins, among which acrylic resins are particularly preferred from the viewpoint of affinity with other components of the semiconductor resin encapsulant, particularly affinity with epoxy resins.

[0098] When an organic filler is used as the filler (D), the content of the organic filler in the epoxy resin composition of the present embodiment can be appropriately set depending on the desired performance and is not particularly limited, but is preferably 1 to 20 mass %, more preferably 2 to 18 mass %, and even more preferably 3 to 16 mass %, relative to the total amount of the epoxy resin composition. When the content of the organic filler is 1 mass % or more, stress relaxation works and the effect of improving adhesive strength tends to be obtained. When the content of the organic filler is 20 mass % or less, the effect of heat reflow resistance tends to be obtained.

[0099] (Component (E): Solvent) The epoxy resin composition of this embodiment may further contain a solvent (hereinafter, may be referred to as solvent (E) or component (E)). The inclusion of solvent (E) tends to facilitate uniform dissolution of the compound of component (C) described above in the epoxy resin composition. This can improve the curing uniformity of the cured product layer made from the epoxy resin composition of this embodiment. Furthermore, by using solvent (E) and selecting component (C) having various structures according to the desired reaction temperature range and reaction rate, performance such as reduced warpage and high heat resistance tends to be further exhibited.

[0100] The solvent (E) is not particularly limited, and known solvents can be used. Examples of the solvent (E) include, but are not limited to, hydrocarbons such as benzene, toluene, xylene, cyclohexane, mineral spirits, and solvent naphtha; ketones such as acetone, methyl ethyl ketone (MEK), methyl isopropyl ketone, methyl isobutyl ketone, cyclohexanone, and acetophenone; esters such as ethyl acetate, n-butyl acetate, propylene glycol monomethyl ethyl ether acetate, and γ-butyrolactone; alcohols such as methanol, ethanol, isopropanol, n-butanol, butyl cellosolve, butyl carbitol, 2-phenoxyethanol, and 1-methoxy-2-propanol; and amide solvents such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone. These may be used alone or in combination of two or more.

[0101] The content of solvent (E) in the epoxy resin composition of this embodiment is not particularly limited, but from the viewpoints of uniformly dissolving the various components and controlling the viscosity within an appropriate range to improve handleability when the composition is used as a varnish or paste by blending the solvent, the content is preferably 5 to 80 mass %, more preferably 10 to 75 mass %, even more preferably 15 to 70 mass %, even more preferably 20 to 65 mass %, and even more preferably 25 to 60 mass % relative to the total epoxy resin composition. Note that when other components contain solvents, such as when component (B) contains a solvent, the above content is a preferred range of the solvent proportion in the total epoxy resin composition, including those solvents.

[0102] Furthermore, when the epoxy resin composition of this embodiment is used as a film-type adhesive, the content of the solvent (E) is not particularly limited, but from the viewpoint of suppressing the generation of bubbles, it is preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 6% by mass or less, based on the total epoxy resin composition. On the other hand, from the viewpoint of preventing a decrease in the adhesion and flexibility of the film-type adhesive due to excessive reduction of the solvent, it is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and even more preferably 0.1% by mass or more, based on the total epoxy resin composition.

[0103] (Component (F): Other Curing Agents) The epoxy resin composition of this embodiment may further contain the above-described component (B): a predetermined curing agent (B) and component (C): a curing agent other than the compounds of general formulas (1) and (2) (hereinafter, sometimes referred to as curing agent (F) or component (F)). Component (F) may be any conventionally known curing agent used in epoxy resins, and is not particularly limited. Examples of component (F) include, but are not limited to, amine-based curing agents, amide-based curing agents, phenol-based curing agents (excluding triazine skeleton-containing phenol-based curing agents), acid anhydride-based curing agents, imidazole-based curing agents (excluding component (C)), carbodiimide-based curing agents, benzoxazine-based curing agents, phosphorus-based curing agents, thiol-based curing agents, catalyst-type curing agents, and modified products thereof. These may be used alone or in combination of two or more.

[0104] Examples of amine curing agents include, but are not limited to, aliphatic amines, aromatic amines, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diazabicyclo(5,4,0)-undecene, etc. Examples of aliphatic amines include, but are not limited to, triethylamine, tributylamine, diethylenetriamine, triethylenetetraamine, tetraethylenepentamine, m-xylenediamine, trimethylhexamethylenediamine, 2-methylpentamethylenediamine, isophoronediamine, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, bis(4-aminocyclohexyl)methane, norbornenediamine, 1,2-diaminocyclohexane, etc. Examples of aromatic amines include, but are not limited to, diaminodiphenylmethane, m-phenylenediamine, diaminodiphenylsulfone, diethyltoluenediamine, trimethylenebis(4-aminobenzoate), polytetramethylene oxide-di-p-aminobenzoate, KAYAHARD AA (trade name) manufactured by Nippon Kayaku Co., Ltd., and Ethacure 100 (trade name) manufactured by Mitsui Fine Chemicals, Inc.

[0105] Examples of amide-based curing agents include, but are not limited to, dicyandiamide and its derivatives, such as guanidine compounds, or amine-based curing agents to which acid anhydrides are added, and hydrazide-based compounds.

[0106] Examples of hydrazide curing agents made of hydrazide compounds include, but are not limited to, succinic acid dihydrazide, adipic acid dihydrazide, phthalic acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide, p-oxybenzoic acid hydrazide, salicylic acid hydrazide, phenylaminopropionic acid hydrazide, and maleic acid dihydrazide.

[0107] Examples of guanidine-based curing agents made of guanidine compounds include, but are not limited to, dicyandiamide derivatives such as dicyandiamide, dicyandiamide-aniline adduct, dicyandiamide-methylaniline adduct, dicyandiamide-diaminodiphenylmethane adduct, and dicyandiamide-diaminodiphenyl ether adduct; guanidine salts such as guanidine nitrate, guanidine carbonate, guanidine phosphate, guanidine sulfamate, and aminoguanidine bicarbonate; methylguanidine, ethylguanidine, propylguanidine, butylguanidine, dimethylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, cyclohexylguanidine, phenylguanidine, diphenylguanidine, toluylguanidine; methylbiguanide, diacetylguanidine, propionylguanidine, dipropionylguanidine, cyanoacetylguanidine, guanidine succinate, diethylcyanoacetylguanidine, dicyandiamidine, N-oxymethyl-N'-cyanoguanidine, N,N'-dicarbethoxyguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, 1-(o-tolyl)biguanide, and the like.

[0108] Examples of phenolic curing agents (excluding triazine skeleton-containing phenolic curing agents) include, but are not limited to, phenol novolac resins, bisphenol A novolac resins, cresol novolac resins, phenol aralkyl resins, cresol aralkyl resins, naphthol-phenol co-condensed novolac resins, naphthol-cresol co-condensed novolac resins, allyl acrylic phenol resins, dicyclopentadiene skeleton-containing phenolic resins, biphenyl skeleton-containing phenolic resins, and naphthalene skeleton-containing phenolic resins. Examples of commercially available phenolic curing agents include those manufactured by DIC Corporation under the trade names TD2090 (phenol novolac resin) and EXB-9500 (naphthalene skeleton-containing phenolic resin), those manufactured by UBE under the trade names HF-1M (phenol novolac resin), MEH-7700, MEH-7810, and MEH-7851 (biphenyl skeleton-containing phenolic resin), those manufactured by Nippon Kayaku Co., Ltd. under the trade names NHN, CBN, and GPH (naphthalene skeleton-containing phenolic resin), and those manufactured by Nippon Steel Chemical & Material Co., Ltd. under the trade names SN170, SN180, SN190, SN475, SN485, SN495, SN375, and SN395 (naphthalene skeleton-containing phenolic resin). Among these, from the viewpoint of improving the heat resistance and strength of the cured product, it is preferable to use a phenolic curing agent having a bisphenol A type structure, a bisphenol F type structure, a bisphenol AF type structure, a naphthalene structure, a phenol novolac structure, a cyclohexane structure, a cyclohexanedimethanol structure, a butadiene structure, a biphenyl type structure, a bixylenol structure, a cresol novolac structure, a dicyclopentadiene structure, a trisphenol structure, a naphthol structure, a naphthylene ether structure, an anthracene structure, a tetraphenylethane structure, a bisphenolacetophenone structure, or a fluorene structure.

[0109] Examples of acid anhydride curing agents include, but are not limited to, phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, hexahydrophthalic anhydride, and methylhexahydrophthalic anhydride.

[0110] The imidazole-based curing agent excluding the component (C) is not limited to the following, but examples thereof include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, and 1-cyanoethyl-2-phenylimidazolium trimellitate. 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine socyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, 2-phenylimidazoline, and the like.

[0111] Examples of carbodiimide curing agents include, but are not limited to, trade names Carbodilite V-02B, V-03, V-04K, V-07, and V-09 manufactured by Nisshinbo Chemical Inc., and trade names Stabaxol P, P400, and Hi-Kasil 510 manufactured by Rhein Chemie. Modified carbodiimide compounds such as those disclosed in Japanese Patent No. 7226954 may also be used.

[0112] Examples of benzoxazine curing agents include, but are not limited to, HFB2006M (trade name) manufactured by Showa Highpolymer Co., Ltd., and Pd, Fa, and ALP-d (trade names) manufactured by Shikoku Kasei Holdings Co., Ltd.

[0113] Examples of phosphorus-based curing agents include, but are not limited to, triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, and butyltriphenylphosphonium thiocyanate.

[0114] The thiol curing agent may be any agent containing two or more thiol groups in one molecule, and is not limited to the following. Examples include 3,3'-dithiodipropionic acid, trimethylolpropane tris(thioglycolate), pentaerythritol tetrakis(thioglycolate), ethylene glycol dithioglycolate, 1,4-bis(3-mercaptobutyryloxy)butane, tris[(3-mercaptopropionyloxy)-ethyl]-isocyanurate, 1,3,5-tris(3-mercaptobutyloxyethyl)-1, Examples of the alkyl acrylate include 3,5-triazine-2,4,6(1H,3H,5H)-trione, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), dipentaerythritol hexakis(3-mercaptopropionate), 1,3,4,6-tetrakis(2-mercaptoethyl)glycoluril, 4-butanedithiol, 1,6-hexaneedithiol, and 1,10-decanedithiol. From the viewpoint of the impact resistance of a cured product of the epoxy resin composition of the present embodiment, 1,4-bis(3-mercaptobutyryloxy)butane, 1,3,5-tris(3-mercaptobutyloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione, pentaerythritol tetrakis(3-mercaptopropionate), and pentaerythritol tetrakis(3-mercaptobutyrate) are preferred, and from the viewpoint of the low-temperature curing ability of the epoxy resin composition of the present embodiment, pentaerythritol tetrakis(3-mercaptopropionate) and pentaerythritol tetrakis(3-mercaptobutyrate) are more preferred.

[0115] The catalyst-type curing agent is not limited to the following, but examples thereof include cationic thermosetting catalysts, BF ３ -amine complexes and the like.

[0116] Modified curing agents include, but are not limited to, polyamine compounds, amine-epoxy adducts, amine-urea adducts, imidazole-epoxy adducts, amine imide compounds, or microcapsule-type curing agents coated with these, curing agents adsorbed on porous bodies, etc. Specific examples include, but are not limited to, products manufactured by Asahi Kasei Corporation under the trade names Novacure HX-3722, HX-3742, HX-3088, HX-3613, HXA3932HP, HXA9322HP, HXA9382HP, and HXA9192HP; products manufactured by Ajinomoto Fine-Techno Co., Inc. under the trade names Amicure PN-23J, PN-40J, and MY-24; and products manufactured by Fuji Chemical Industry Co., Ltd. under the trade names Fujicure FXR-1020 and FXR-1030.

[0117] Among the above, component (F) preferably contains a carbodiimide-based curing agent from the viewpoints of improving the adhesion between the epoxy resin composition of the present embodiment and substrate materials, and of increasing the crosslink density by reacting with various active hydrogen groups to sufficiently develop strength of the cured product. Furthermore, component (F) preferably contains a benzoxazine-based curing agent from the viewpoints of obtaining a cured product excellent in dimensional stability, high flame retardancy, low dielectric loss tangent, and low water absorption.

[0118] The content of component (F) in the epoxy resin composition of this embodiment can be appropriately set depending on the reactivity of the above-mentioned components (B) and (C) and the desired performance, and is not particularly limited, but from the viewpoint of obtaining good reactivity, it is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and even more preferably 1.0% by mass or more of all non-volatile components excluding the solvent. Furthermore, from the viewpoint of obtaining good storage stability, it is preferably 40% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less.

[0119] (Component (G): Thermoplastic Resin) The epoxy resin composition of the present embodiment may further contain a thermoplastic resin (hereinafter, may be referred to as thermoplastic resin (G) or component (G)). By containing the thermoplastic resin (G), when the epoxy resin composition of the present embodiment is formed into a film by casting or applying it to a certain thickness and drying it, it is possible to prevent cracks and breaks and maintain the film shape.

[0120] Examples of the thermoplastic resin (G) include, but are not limited to, phenoxy resin, polyvinyl acetal resin, acid anhydride group-containing vinyl resin, polyolefin resin, polybutadiene resin, polyimide resin, polyamide-imide resin, styrene-based elastomer resin, polyether sulfone resin, polyphenylene ether resin, polysulfone resin, acrylic resin, etc. The thermoplastic resin (G) may be used singly or in combination of two or more.

[0121] From the viewpoint of obtaining a cured layer having sufficient strength using the epoxy resin composition of this embodiment, the weight average molecular weight of the thermoplastic resin (G) is preferably 10,000 or more, more preferably 15,000 or more, even more preferably 20,000 or more, still more preferably 25,000 or more, and even more preferably 30,000 or more. From the viewpoint of obtaining good compatibility, the upper limit of the weight average molecular weight of the thermoplastic resin (G) is preferably 200,000 or less, more preferably 180,000 or less, even more preferably 160,000 or less, and still more preferably 150,000 or less. The weight average molecular weight of the thermoplastic resin (G) can be measured, for example, by gel permeation chromatography (GPC). Specifically, the weight average molecular weight (polystyrene equivalent) of the thermoplastic resin can be measured at a column temperature of 40°C using a measuring device HLC-8320GPC manufactured by Tosoh Corporation, a column Shodex KF-804 / KF-803 / KF-802 / KF-802 manufactured by Resonac Inc., and tetrahydrofuran or the like as a mobile phase, and can be calculated using a calibration curve of standard polystyrene.

[0122] From the viewpoint of increasing the crosslink density of the cured product of the epoxy resin composition of this embodiment and ensuring sufficient heat resistance and strength of the cured product layer, it is preferable that the thermoplastic resin (G) has a functional group containing one or more atoms selected from the group consisting of oxygen atoms, nitrogen atoms, and sulfur atoms, or a carbon-carbon double bond. Examples of such functional groups include one or more selected from the group consisting of hydroxyl groups, carboxy groups, acid anhydride groups, epoxy groups, amino groups, thiol groups, enol groups, enamine groups, urea groups, cyanate groups, isocyanate groups, thioisocyanate groups, diimide groups, alkenyl groups, allene groups, and ketene groups. The acid anhydride group is preferably a carboxylic acid anhydride group. Suitable examples of alkenyl groups include vinyl groups, allyl groups, and styryl groups. When the thermoplastic resin contains such a functional group, the functional group equivalent of the thermoplastic resin (G) is preferably 100,000 or less, more preferably 90,000 or less, 80,000 or less, 70,000 or less, 60,000 or less, 50,000 or less, 40,000 or less, 30,000 or less, 20,000 or less, 10,000 or less, 8,000 or less, 6,000 or less, or 5,000 or less. The lower limit of the functional group equivalent is not particularly limited, but can usually be 50 or more, 100 or more, etc.

[0123] Suitable thermoplastic resins (G) will be described in more detail below, but thermoplastic resins obtained by further adding the above-mentioned functional groups to the thermoplastic resins shown below in accordance with known procedures can also be suitably used as component (G).

[0124] Suitable examples of the phenoxy resin include phenoxy resins having one or more skeletons selected from the group consisting of a bisphenol A skeleton, a bisphenol F skeleton, a bisphenol S skeleton, a bisphenolacetophenone skeleton, a phenol novolac skeleton, a biphenyl skeleton, a fluorene skeleton, a dicyclopentadiene skeleton, a norbornene skeleton, a naphthalene skeleton, an anthracene skeleton, an adamantane skeleton, a terpene skeleton, and a trimethylcyclohexane skeleton, and the terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. Specific examples of phenoxy resins include Mitsubishi Chemical Corporation's product names: 1256 and 4250 (phenoxy resin containing a bisphenol A skeleton), YX8100 (phenoxy resin containing a bisphenol S skeleton), YX6954 and YX6954BH30 (phenoxy resin containing a bisphenol acetophenone skeleton), YX7553 and YX7553BH30 (phenoxy resin containing a biscresol fluorenone skeleton), YL6794 (phenoxy resin containing a terpene skeleton), YL7213 and YL7290 (phenoxy resin containing a trimethylcyclohexane skeleton), YL7500BH30, YL7769BH30, and YL7482; and Nippon Steel Chemical & Material Co., Ltd.'s product names: FX280 and FX293 (phenoxy resin containing a bisphenol fluorenone skeleton).

[0125] Specific examples of polyvinyl acetal resins include Denka Butyral 4000-2, 5000-A, 6000-C, and 6000-EP, both manufactured by Denki Kagaku Kogyo Co., Ltd.; and S-LEC BH series, BX series, KS series (e.g., KS-1), BL series, and BM series, both manufactured by Sekisui Chemical Co., Ltd.

[0126] Examples of acid anhydride group-containing vinyl resins include copolymers of an acid anhydride group-containing monomer (d1) and another monomer (d2). Examples of the acid anhydride group-containing monomer (d1) include maleic anhydride, itaconic anhydride, citraconic anhydride, and aconitic anhydride. The other monomer (d2) is not particularly limited as long as it can be copolymerized with the acid anhydride group-containing monomer (d1), and examples include ethylenically unsaturated monomers such as (meth)acrylic acid, (meth)acrylic acid esters, and styrene. Specific examples of acid anhydride group-containing vinyl resins include Cray Valley Corporation's product names: EF-30, EF-40, EF-60, and EF-80.

[0127] Specific examples of polyimide resins include those manufactured by New Japan Chemical Co., Ltd. under the trade names of Rikacoat SN-20 and PN-20, and those manufactured by DIC Corporation under the trade name of Unidic V-8000. Specific examples of polyimide resins also include modified polyimides such as linear polyimides obtained by reacting bifunctional hydroxyl group-terminated polybutadiene, a diisocyanate compound, and a tetrabasic acid anhydride (JP 2006-37083 A), and polysiloxane skeleton-containing polyimides (JP 2002-12667 A, JP 2000-319386 A, WO 2010 / 53186 A, etc.).

[0128] Specific examples of polyamide-imide resins include Viromax HR11NN and HR16NN (trade names) manufactured by Toyobo Co., Ltd., and HPC-5020, HPC-6000, HPC-7200, and HPC-9000 (trade names) manufactured by Resonac Co., Ltd.

[0129] Examples of styrene-based elastomer resins include block copolymers containing a block of styrene or an analog thereof as at least one terminal block and an elastomer block of a conjugated diene or its hydrogenated product as at least one intermediate block. Specific examples include styrene-butadiene diblock copolymers, styrene-butadiene triblock copolymers, styrene-isoprene diblock copolymers, styrene-isoprene triblock copolymers, hydrogenated styrene-butadiene diblock copolymers, hydrogenated styrene-butadiene triblock copolymers, hydrogenated styrene-isoprene diblock copolymers, hydrogenated styrene-isoprene triblock copolymers, and hydrogenated styrene-butadiene random copolymers. Specific examples of styrene-based elastomer resins include Asahi Kasei Corporation's Asaprene, Tufprene, and Asaflex products, and Kuraray Co., Ltd.'s Hybler and Septon products.

[0130] A specific example of the polyethersulfone resin is PES5003P, a product of Sumitomo Chemical Co., Ltd.

[0131] Specific examples of polysulfone resins include Polysulfone P1700 and P3500, trade names of which are manufactured by Solvay Advanced Polymers.

[0132] Specific examples of polybutadiene resins include those manufactured by Nippon Soda Co., Ltd. under the trade names G-1000, G-3000, GI-1000, and GI-3000, those manufactured by Idemitsu Petrochemical Co., Ltd. under the trade name R-45EPI, those manufactured by Daicel Corporation under the trade name Epofriend AT501, and those manufactured by Cray Valley Corporation under the trade names Ricon 130, Ricon 142, Ricon 150, Ricon 657, and Ricon 130MA.

[0133] Specific examples of the acrylic resin include trade names SG-P3, SG-600LB, SG-280, SG-790, and SG-K2 manufactured by Nagase ChemteX Corporation, and trade names SN-50, AS-3000E, and ME-2000 manufactured by Negami Chemical Industrial Co., Ltd.

[0134] In particular, from the viewpoints of ensuring sufficient heat resistance and strength of the cured product layer obtained using the epoxy resin composition of the present embodiment, ensuring long-term connection reliability, and maintaining appropriate compatibility with the epoxy resin (A) and ensuring curing uniformity, it is preferable that the thermoplastic resin (G) contains one or more resins selected from the group consisting of phenoxy resins, polyvinyl acetal resins, acid anhydride group-containing vinyl resins, polyimide resins, polyamide-imide resins, styrene-based elastomer resins, and acrylic resins.

[0135] Furthermore, when the epoxy resin composition of this embodiment is used in materials that are folded and incorporated into electronic devices, such as flexible wiring boards, the inclusion of a thermoplastic resin (G) can reduce the elasticity of the cured layer of the epoxy resin composition, thereby preventing breakage and peeling. For applications requiring such reduced elasticity, the thermoplastic resin (G) is not limited to the following, but for example, a resin having one or more structures selected from a polybutadiene structure, a polysiloxane structure, a poly(meth)acrylate structure, a polyalkylene structure, a polyalkyleneoxy structure, a polyisoprene structure, a polyisobutylene structure, and a polycarbonate structure in the molecule is preferred, as this makes it easier to achieve the reduced elasticity effect. Furthermore, a thermoplastic resin having a glass transition temperature of 25°C or lower or that is liquid at 25°C can also be used preferably from the viewpoint of achieving the same reduced elasticity effect.

[0136] The content of thermoplastic resin (G) in the epoxy resin composition of this embodiment can be appropriately set depending on the contents and types of epoxy resin (A), curing agent (B), and other curing agents used, the content of filler (D), and the desired performance of the epoxy resin composition of this embodiment, and is not particularly limited, but from the viewpoint of ensuring the adhesion and flexibility of the epoxy resin composition of this embodiment, it is preferably 0.5% by mass or more, more preferably 1% by mass or more, even more preferably 1.2% by mass or more, and even more preferably 1.5% by mass or more of all non-volatile components excluding solvents. From the viewpoint of maintaining good heat resistance and strength of the epoxy resin composition of this embodiment, it is preferably 50% by mass or less, more preferably 40% by mass or less, even more preferably 30% by mass or less, and even more preferably 20% by mass or less.

[0137] (Component (H): Silane Coupling Agent) The epoxy resin composition of the present embodiment may further contain a silane coupling agent (hereinafter, may be referred to as silane coupling agent (H) or component (H)). By containing the silane coupling agent (H), the affinity between the resin component and the filler, or between the resin component and the substrate to be adhered, can be improved, the uniform dispersion of the filler component is improved, and the adhesiveness of the epoxy resin composition tends to be improved, which is preferable.

[0138] In this embodiment, "containing a silane coupling agent (H)" means that in the step of obtaining the epoxy resin composition of this embodiment, the silane coupling agent is incorporated into the epoxy resin composition by any of the following methods (i) to (iii). Method (i): A method in which the filler (D) is treated with a silane coupling agent and the treated filler is blended into the epoxy resin composition. Method (ii): A method in which the silane coupling agent is added directly to the epoxy resin composition (integral blend method). Method (iii): A method in which the silane coupling agent is reacted with the resin terminal or side chain of the epoxy resin (A) or thermoplastic resin (G) used, or a method in which the silane coupling agent is blended as a silylated resin, such as by using a resin obtained by copolymerizing a monomer and a silane coupling agent.

[0139] Any of the above-mentioned methods (i) to (iii) may be used, and method (i) is preferred from the viewpoint that alcohol, which is a by-product of the silane coupling reaction, is less likely to remain in the system and that the dispersibility of the filler is even better. Methods (ii) and (iii) are preferred from the viewpoint that affinity can be exerted not only between the resin and the filler but also between the resin and the substrate to be adhered, thereby improving the adhesiveness and adhesion.

[0140] The silane coupling agent (H) is a silicon atom to which at least one hydrolyzable group such as an alkoxy group or an aryloxy group is bonded, and in addition, an alkyl group, an alkenyl group, or an aryl group may be bonded.The alkyl group may also be substituted with an amino group, an alkoxy group, an epoxy group, or a (meth)acryloyloxy group.The silane coupling agent (H) is not limited to the following, but from the viewpoint of improving the uniform dispersion of the filler component and improving the adhesiveness and adhesion of the resin composition, it is preferable to include one or more silane coupling agents selected from, for example, aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, styrylsilane coupling agents, acrylate silane coupling agents, isocyanate silane coupling agents, sulfide silane coupling agents, vinylsilane coupling agents, silane coupling agents, organosilazane compounds, and titanate coupling agents.

[0141] Specific examples of the silane coupling agent (H) include aminosilane coupling agents such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, N-phenyl-3-aminopropyltrimethoxysilane, N-methylaminopropyltrimethoxysilane, N-2(aminoethyl)-3-aminopropyltrimethoxysilane, and N-(2-aminoethyl)-3-aminopropyldimethoxymethylsilane; 3-glycidyloxypropyltrimethoxysilane; epoxysilane-based coupling agents such as propyltriethoxysilane, 3-glycidyloxypropylmethyldiethoxysilane, 3-glycidyloxypropyl(dimethoxy)methylsilane, glycidylbutyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; mercaptosilane-based coupling agents such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and 11-mercaptoundecyltrimethoxysilane; p-styryltrimethoxysilane; styrylsilane coupling agents such as methoxysilane; acrylate silane coupling agents such as 3-acryloxypropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, and 3-methacryloxypropyldiethoxysilane; isocyanate silane coupling agents such as 3-isocyanatepropyltrimethoxysilane; bis(triethoxysilylpropyl)disulfide, bis(triethoxysilylpropyl)tetramethylsilane; Sulfide silane coupling agents such as sulfides, silane coupling agents such as methyltrimethoxysilane, octadecyltrimethoxysilane, phenyltrimethoxysilane, metachloroxypropyltrimethoxysilane, imidazole silane, triazine silane, and t-butyltrimethoxysilane, hexamethyldisilazane, 1,3-divinyl-1,1,3,3-tetramethyldisilazane, hexaphenyldisilazane, trisilazane, cyclotrisilazane, octamethylcyclotetrasilazane, hexabutyldisilazane, hexaoctyldisilazane, 1,Organosilazanes such as 3-diethyltetramethyldisilazane, 1,3-di-n-octyltetramethyldisilazane, 1,3-diphenyltetramethyldisilazane, 1,3-dimethyltetraphenyldisilazane, 1,3-diethyltetramethyldisilazane, 1,1,3,3-tetraphenyl-1,3-dimethyldisilazane, 1,3-dipropyltetramethyldisilazane, hexamethylcyclotrisilazane, dimethylaminotrimethylsilazane, and tetramethyldisilazane Titanium compounds, tetra-n-butyl titanate dimer, titanium i-propoxyoctylene glycolate, tetra-n-butyl titanate, titanium octylene glycolate, diisopropoxytitanium bis(triethanolaminate), dihydroxytitanium bislactate, dihydroxybis(ammonium lactate)titanium, bis(dioctyl pyrophosphate)ethylene titanate, bis(dioctyl pyrophosphate)oxyacetate titanate ate, tri-n-butoxytitanium monostearate, tetra-n-butyl titanate, tetra(2-ethylhexyl) titanate, tetraisopropyl bis(dioctyl phosphite) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl)phosphite titanate, isopropyl trioctanoyl titanate, isopropyl tricumyl phenyl titanate, isopropyl bis(dioctyl phosphite) titanate, Examples of titanate coupling agents include propyl triisostearoyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tridodecylbenzenesulfonyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, and isopropyl tri(N-amidoethyl aminoethyl) titanate.

[0142] Among these, aminosilane coupling agents, epoxysilane coupling agents, mercaptosilane coupling agents, and organosilazane compounds are preferred, and aminosilane coupling agents are more preferred. Examples of commercially available products include those manufactured by Shin-Etsu Chemical Co., Ltd. under the trade names: KBM403 (3-glycidoxypropyltrimethoxysilane), KBM803 (3-mercaptopropyltrimethoxysilane), KBE903 (3-aminopropyltriethoxysilane), KBM573 (N-phenyl-3-aminopropyltrimethoxysilane), and SZ-31 (hexamethyldisilazane).

[0143] The content of the silane coupling agent (H) in the epoxy resin composition of the present embodiment is not particularly limited, but from the viewpoint of improving the dispersibility of the filler (D) and the adhesiveness and adhesion of the epoxy resin composition of the present embodiment while suppressing excessive side reactions, it is preferably 0.1 to 2.0 parts by mass per 100 parts by mass of the filler (D).

[0144] (Additives) In addition to the above-described components (A) to (H), the epoxy resin composition of the present embodiment may further contain, as necessary, additives such as diluents, reactive diluents, pigments, dyes, flow modifiers, thickeners, toughening agents, release agents, wetting agents, flame retardants, surfactants, stabilizers, and adhesion aids.

[0145] The diluent is not limited to, but includes, for example, dioctyl phthalate, dibutyl phthalate, benzyl alcohol, and the like.

[0146] The reactive diluent is a compound having a reactive functional group that can be incorporated into the cured structure of an epoxy group, an acrylic group, or the like, and is a compound that has the effect of lowering the viscosity of the epoxy resin composition when added to the epoxy resin composition of this embodiment. Examples of the reactive diluent include, but are not limited to, acrylate compounds and epoxy compounds that can lower the viscosity without impairing reactivity.

[0147] Examples of the acrylate compound that is a reactive diluent include, but are not limited to, a compound having (meth)acryloyl groups at both ends of a polyalkylene oxide, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polybutylene glycol di(meth)acrylate, trimethylolpropane-type polyfunctional (meth)acrylate, pentaerythritol-type polyfunctional (meth)acrylate, and dipentaerythritol-type polyfunctional (meth)acrylate.

[0148] Examples of the epoxy compound that is a reactive diluent include, but are not limited to, n-butyl glycidyl ether, tert-butyl glycidyl ether, diglycidyl aniline, N,N'-glycidyl-o-toluidine, phenyl glycidyl ether, cresyl glycidyl ether, p-tert-butylphenyl glycidyl ether, styrene oxide, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, and 1,6-hexanediol diglycidyl ether.

[0149] Various monoepoxy compounds and glycidyl ether compounds of polyhydric alcohols can also be used as reactive diluents. However, these compounds have only one functional group (epoxy group, glycidyl group) per molecule that contributes to the reaction with components (B), (C), and (F). Although these compounds do not volatilize and cause voids, they tend to be unable to form three-dimensional crosslinks upon curing, making it difficult to ensure sufficient heat resistance and toughness for the cured product of the epoxy resin composition. Therefore, from the viewpoint of being able to form three-dimensional crosslinks upon curing and suppressing a decrease in heat resistance and toughness upon curing, a compound containing two or more glycidyl groups per molecule is preferred as the reactive diluent. The reactive diluents may be used alone or in combination of two or more.

[0150] The content of the reactive diluent can be appropriately set depending on the desired performance of the epoxy resin composition of this embodiment and is not particularly limited, but is preferably 1.0 part by mass or more and 30 parts by mass or less per 100 parts by mass of the epoxy resin (A). A content of 1.0 part by mass or more tends to suppress an increase in viscosity of the epoxy resin composition of this embodiment at room temperature, and to suppress deterioration of embeddability when used as a film for embedding wiring. Furthermore, a decrease in heat resistance and toughness during curing tends to be suppressed, and the occurrence and progression of fillet cracks tends to be suppressed. On the other hand, a content of the reactive diluent of 30 parts by mass or less per 100 parts by mass of the epoxy resin (A) tends to suppress a decrease in adhesion and to suppress peeling during a moisture absorption reflow test. It is also preferable to further contain a reactive diluent to suppress an increase in viscosity that occurs when the filler (D) is highly loaded.

[0151] Examples of pigments include, but are not limited to, kaolin, chalk powder, gypsum, antimony trioxide, pentone, aerosol, lithopone, baryte, and titanium dioxide.

[0152] Examples of dyes include, but are not limited to, natural dyes such as plant-derived dyes such as madder and indigo, and mineral-derived dyes such as yellow ochre and red clay, synthetic dyes such as alizarin and indigo, and fluorescent dyes.

[0153] Examples of flow control agents include, but are not limited to, organic titanium compounds such as titanium tetraisopropoxide and titanium diisopropoxybis(acetylacetonate); and organic zirconium compounds such as zirconium tetra-normal-butoxide and zirconium tetraacetylacetonate.

[0154] Examples of thickeners include, but are not limited to, animal-based thickeners such as gelatin; plant-based thickeners such as polysaccharides and cellulose; and chemically synthesized thickeners such as polyacrylics, modified polyacrylics, polyethers, urethane-modified polyethers, and carboxymethylcellulose.

[0155] Examples of the reinforcing agent include, but are not limited to, polyethylene sulfone powder such as "Sumikaexcel PES" manufactured by Sumitomo Chemical Co., Ltd.; nano-sized functional group-modified core-shell rubber particles such as "Kane Ace MX" manufactured by Kaneka Corporation; and silicone-based reinforcing agents such as polyorganosiloxane.

[0156] Examples of the release agent include, but are not limited to, fluorine-based release agents, silicone-based release agents, and acrylic release agents made of a copolymer of glycidyl (meth)acrylate and a linear alkyl (meth)acrylate having 16 to 22 carbon atoms.

[0157] Examples of wetting agents include, but are not limited to, unsaturated polyester copolymer wetting agents having acidic groups, such as acrylic polyphosphate esters.

[0158] Examples of flame retardants include, but are not limited to, bromine-based flame retardants, phosphorus-based flame retardants, and inorganic flame retardants. Bromine-based flame retardants include, but are not limited to, tetrabromophenol. Phosphorus-based flame retardants include, but are not limited to, 9,10-dihydro-9-oxa-10-phosphananthrene-10-oxide and its epoxy derivatives, triphenylphosphine and its derivatives, phosphate esters, condensed phosphate esters, and phosphazene compounds. Nitrogen-based flame retardants include, but are not limited to, melamine polyphosphate, isocyanuric acid, guanidine-based flame retardants, and triazine-based flame retardants. Inorganic flame retardant compounds include, but are not limited to, magnesium hydroxide and aluminum hydroxide. Phosphazene compounds and magnesium hydroxide are preferred from the standpoint of heat resistance. The phosphazene compounds disclosed in Japanese Patent Publication No. 723041 can also be used. The flame retardant may be used alone or in combination of two or more. The content of the flame retardant is not particularly limited, but is preferably 5.0 parts by mass or more and 200 parts by mass or less, more preferably 10 parts by mass or more and 100 parts by mass or less, relative to the mass (100 parts by mass) of the epoxy resin (A).

[0159] Examples of surfactants include, but are not limited to, anionic surfactants such as alkylbenzene sulfonates and alkyl polyoxyethylene sulfates, cationic surfactants such as alkyl dimethyl ammonium salts, amphoteric surfactants such as alkyl dimethyl amine oxides and alkyl carboxy betaines, and nonionic surfactants such as linear alcohols and fatty acid esters having 25 or more carbon atoms.

[0160] As stabilizers that improve the storage stability of epoxy resin compositions, for example, boric acid, cyclic borate ester compounds, isocyanuric acid, barbituric acid, aluminum chelating agents, etc. can be suitably used, but are not limited to these. A cyclic borate ester compound is one in which boron is contained in a cyclic structure. From the viewpoints of compatibility with the resin and uniformity of curing, the cyclic borate ester compound is preferably 2,2'-oxybis(5,5'-dimethyl-1,3,2-oxaborinane). Note that one stabilizer may be used alone, or two or more stabilizers may be used in combination.

[0161] A wide variety of adhesion aids can be used as long as they are components that are added for the purpose of forming coordinate bonds with metals or substrate materials or improving affinity. However, from the viewpoint of further obtaining the effect of forming a good coating on the surface of the adherend and improving adhesion, thiazole-based compounds and triazole-based compounds are preferred.

[0162] The additives described above can be added in functionally appropriate amounts, for example, pigments and / or dyes can be added in amounts that can impart a desired color to the epoxy resin composition of the present embodiment. In addition, a person skilled in the art can appropriately determine the amount of additives to be added depending on the formulation and the desired performance.

[0163] [Epoxy Resin Composition and Resin Paste Using the Same] The epoxy resin composition of this embodiment and the resin paste using the same contain the above-described components (A) to (C), and can be obtained by adding, as needed, components (D) to (H) and the above-described additives, and mixing them. That is, the resin paste of this embodiment contains the epoxy resin composition of this embodiment. The mixing method is not particularly limited, and methods known to those skilled in the art can be applied. For example, the composition can be obtained by thoroughly mixing until homogeneous using, but not limited to, a mixing roll such as a three-roll mixer, a dissolver, a planetary mixer, a rotary mixer, a kneader, an extruder, or the like.

[0164] (Specific Aspects of Epoxy Resin Composition and Resin Paste Using the Same) The epoxy resin composition of the present embodiment not only achieves both stability and reactivity, but also excels in low warpage, high heat resistance, and high strength. Therefore, it can be used as a sealing material for electric and electronic components such as a relay sealant; paste materials such as various insulating liquid adhesives, die attach pastes, conductive pastes, and thermally conductive pastes; ink materials such as solder resist inks and hole-filling inks; matrix resins for fiber-reinforced plastics; and impregnating and fixing materials for motor coils. In particular, solvents are often added to paste materials and ink materials. In the case of the epoxy resin composition of the present embodiment containing component (C), component (C) dissolves uniformly in the solvent, so no granular residue is generated when the paste or ink is applied or filled, and a cured product with high curing uniformity is obtained. Therefore, the epoxy resin composition of the present embodiment is more preferable because it has excellent strength and long-term durability. Low warpage, high heat resistance and high strength are common properties required for liquid adhesives, matrix resins for fiber-reinforced plastics and impregnating adhesives for motor coils, and the epoxy resin composition of the present embodiment satisfies these requirements and is suitable for all of these applications.

[0165] [Film-type adhesive] The epoxy resin composition of the present embodiment can be made into a film-type adhesive. The film-type adhesive of the present embodiment has, for example, a predetermined support and a resin layer containing the epoxy resin composition of the present embodiment described above, and may optionally have a protective layer on the surface of the resin layer opposite the support.

[0166] (Support) The support constituting the film-type adhesive is preferably a material that can withstand the temperature during solvent drying.Such a support is not limited to the following, but includes, for example, polyethylene terephthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, polymethyl methacrylate copolymer film, polystyrene film, polyacrylonitrile film, styrene copolymer film, polyamide film, cellulose derivative film, etc.As these films, stretched films can also be used as needed.

[0167] (Protective Layer) The protective layer is preferably made of a material that can sufficiently maintain the surface smoothness of the resin layer that constitutes the film-type adhesive. Examples of such protective layers include, but are not limited to, polyethylene films, polypropylene films, polyethylene terephthalate films that have been treated to be easily peeled, and oriented polypropylene films.

[0168] (Method for Producing Film-Type Adhesive) The film-type adhesive of this embodiment can be produced by sequentially laminating a support, a resin layer, and, if necessary, a protective layer. Known methods can be used to laminate the support, resin layer, and protective layer. For example, the epoxy resin composition of this embodiment containing solvent (E) is prepared, and then coated onto a support using a known method such as an applicator, bar coater, lip coater, die coater, roll coater, or doctor blade coater, followed by drying to form a resin layer on the support. The drying method is not particularly limited, but examples include oven drying and hot air blowing. The drying temperature and time are also not particularly limited. However, from the viewpoint of thoroughly removing the solvent and suppressing deformation of the support due to excessive heating and excessive reaction of the resin layer during drying, drying at a temperature range of 50°C to 160°C for 1 to 30 minutes is preferred, and drying at 80°C to 150°C for 3 to 25 minutes is more preferred. The drying temperature may be a constant temperature or a temperature gradient may be applied. Next, if necessary, a protective layer is laminated on the formed resin layer, thereby producing a film-type adhesive.

[0169] (Specific Aspects of Film-Type Adhesive) The film-type adhesive of this embodiment can be used, for example, as an interlayer insulating film, a film-type solder resist, an encapsulating sheet for semiconductor packages, a die attach film, a conductive film, an anisotropically conductive film, a non-conductive film, a thermally conductive film, and the like, without being limited thereto. A film-type adhesive using the epoxy resin composition of this embodiment not only exhibits the various stabilities required in the production of a film-type adhesive, such as varnish storage stability until coating and drying, stability at drying temperatures, and film storage stability, but also combines low warpage, heat resistance, and strength of the cured product layer. Therefore, it is particularly effective for materials that are prone to warpage, such as film-type adhesives, and that must ensure high strength and reliability in the thin cured product layer. Furthermore, because component (C) dissolves uniformly in the epoxy resin composition or solvent, the film-type adhesive of this embodiment has excellent surface smoothness and can be adhered to a substrate without gaps. The above-mentioned properties are commonly required for interlayer insulating films, film-type solder resists, sealing sheets for semiconductor packages, die attach films, conductive films, anisotropically conductive films, non-conductive films, thermally conductive films, etc., and therefore the film-type adhesive of this embodiment is suitable for these applications.

[0170] [Printed Wiring Board] The printed wiring board of this embodiment has a cured product layer of the epoxy resin composition of this embodiment. When manufacturing a printed wiring board using the film-type adhesive of this embodiment described above, the film-type adhesive manufactured by the above method is attached to a patterned inner layer circuit board, and laminated while applying pressure and heat from the support side. The inner layer circuit surface may be pre-roughened. Lamination is performed under normal or reduced pressure, either batchwise or continuously using a roll, but simultaneous lamination on both sides is preferred. The lamination conditions are preferably a pressure bonding temperature of 70°C to 150°C and a pressure bonding pressure of 0.1 to 1 MPa. Furthermore, to prevent the generation of voids, lamination is preferably performed under reduced pressure of 2 KPa or less. After lamination, the adhesive film is cooled to room temperature, the support film is peeled off, and the adhesive film laminated on the inner layer circuit board is heat-cured to form a cured product layer. Curing conditions are preferably a curing temperature of 130 to 200°C and a curing time of 30 to 120 minutes.

[0171] Next, via holes are drilled using a laser such as a carbon dioxide laser, and then roughening treatment is performed using an oxidizing agent such as permanganate, dichromate, or ozone to remove smears and improve adhesion with the plating. Subsequently, conductor circuits are selectively formed on the cured product layer using electroless plating or electrolytic plating, and simultaneously, conductors are formed on the inner walls of the via holes to form outer layer circuits. Annealing is then performed at 150 to 200°C for 30 to 60 minutes to improve adhesion between the conductor layer and the resin layer. By repeating the above manufacturing process using a film-type adhesive on the conductor circuit layer thus obtained, multiple build-up layers can be formed to produce a printed wiring board.

[0172] As described above, the cured product of the epoxy resin composition of the present embodiment has little warpage, high heat resistance, and high strength, and therefore can be widely used for printed wiring boards such as rigid substrates, flexible substrates, single-area laminate substrates, and thin substrates, and can be particularly suitably used as a build-up layer for multilayer printed wiring boards.

[0173] [Semiconductor Chip Package] The semiconductor chip package of this embodiment has a cured product layer of the epoxy resin composition of this embodiment. By using the film-type adhesive of this embodiment, a semiconductor chip package with low warpage, excellent heat resistance, and strength can be produced. In particular, since a large-area substrate is used, it is suitable for use in wafer-level packages and panel-level packages, where low warpage is important. The film-type adhesive may be laminated on both sides or one side of the substrate used. Various methods for manufacturing packages have been devised, but they can be broadly divided into fan-in structures and fan-out structures.

[0174] When a fan-in semiconductor chip package is manufactured using the film-type adhesive produced as described above, for example, the film-type adhesive produced by the above method is laminated on a substrate such as a silicon wafer on which circuits, elements, and electrode pads are formed and cured to obtain a cured layer. The lamination and curing conditions may be the same as those used when manufacturing a printed wiring board, or may be changed as appropriate depending on the heat resistance, etc., of the elements used. Subsequently, a circuit layer is obtained by forming a rewiring layer on the cured layer through drilling, smear removal, electroless plating, and electrolytic plating. Further, a multilayer circuit can be formed by repeating the lamination and circuit layer formation as necessary. Subsequently, solder balls are arranged so as to be electrically connected to the circuit layer, and the substrate is diced into individual pieces to produce the fan-in semiconductor chip package of the present invention. Note that, before laminating the film-type adhesive on the substrate, columnar electrodes may be formed on the electrode pads, and after curing the film-type adhesive, the circuit layer may be formed by polishing the upper surface of the cured layer until the columnar electrode surfaces are exposed.

[0175] When a fan-out semiconductor chip package is manufactured using the film-type adhesive produced as described above, for example, a substrate such as a silicon wafer is diced into individual pieces, and each individual piece is rearranged and fixed on a support via a film such as a die attach film. The film-type adhesive of this embodiment is then laminated onto the individual pieces and cured to form a cured layer. Subsequently, a rewiring layer is formed on the cured layer by drilling, smear removal, electroless plating, and electrolytic plating to obtain a circuit layer. Further, multilayer circuits can be formed by repeating the lamination and circuit layer formation as necessary. Subsequently, solder balls are arranged so as to be electrically connected to the circuit layer, thereby manufacturing a fan-out semiconductor chip package. Circuits, elements, and electrode pads may be formed in advance before dicing the substrate. In this case, after rearrangement to form a cured layer, openings can be formed in the electrode pad areas by etching, and a circuit layer can be formed in the openings by plating. A fan-out semiconductor chip package can also be manufactured by subsequently forming a circuit pattern and electrodes on the cured layer using a photoresist material, and then arranging solder balls so as to be electrically connected to the circuit.

[0176] [Electronic Device] The electronic device of this embodiment includes the printed wiring board and / or semiconductor chip package of this embodiment described above. The printed wiring board and semiconductor chip package of this embodiment have a cured material layer with low warpage, high heat resistance, and high strength. Therefore, even when mounted on an electronic device that is miniaturized, downsized, and highly dense, they can prevent poor connection and cracks due to warpage and can withstand heat generated by the increasing volume of electronic information handled. Therefore, the resulting electronic device has excellent long-term reliability, which is preferable.

[0177] The electronic device is not particularly limited as long as it is a device that functions by incorporating electronic components, and examples include electrical appliances such as personal computers, smartphones, game consoles, digital cameras and televisions, vehicles such as motorcycles, automobiles, trains, ships and aircraft, and various electronic devices used in high-speed communication antennas, servers, etc.

[0178] The electronic device of this embodiment can be manufactured by mounting various semiconductor chips at the circuit connection locations on the printed wiring board to ensure electrical continuity.

[0179] The method for mounting a semiconductor chip when manufacturing the electronic device of this embodiment is not particularly limited, but specific examples include a wire bonding mounting method, a flip chip mounting method, a mounting method using a bumpless build-up layer (BBUL), a mounting method using an anisotropic conductive film, a mounting method using a non-conductive film, etc. Furthermore, in mounting, the epoxy resin composition of this embodiment, and a resin paste or film-type adhesive using the same can be used to seal, bond, etc. the semiconductor chip.

[0180] Hereinafter, the present embodiment will be described with reference to specific examples and comparative examples, but the present invention is not limited to the following examples and comparative examples and can be appropriately modified within the scope of the invention. In the following, "parts" and "%" are based on mass unless otherwise specified.

[0181] [Preparation of Epoxy Resin Compositions] Epoxy resin compositions were obtained by weighing out each component in the number of parts shown in Tables 1 to 3 below and mixing them until they were sufficiently uniform. In the tables, the number of parts of component (B) is listed including the solvent in cases where the solvent is contained in the product used, as described below.

[0182] [Methods for measuring and evaluating properties] (Evaluation of varnish storage stability: measurement of varnish thickening ratio) The viscosity of the epoxy resin composition immediately after preparation (initial viscosity) and the viscosity of the epoxy resin composition after storage at 25°C for two weeks were measured at room temperature (25°C) using an E-type viscometer (TVE-35H, manufactured by Toki Sangyo Co., Ltd.), and the varnish thickening ratio was calculated using the following formula (1): Varnish thickening ratio (times) = Viscosity after storage at 25°C for two weeks / Initial viscosity Formula (1) The thickening ratio was evaluated as preferably 1.5 times or less, more preferably 1.2 times or less, even more preferably 1.1 times or less, and even more preferably 1.0 times. In Tables 1 to 3 below, epoxy resin compositions that showed such significant thickening after storage that viscosity measurement was impossible were designated as gelled.

[0183] (Evaluation of Curability: Visual Inspection) Using the prepared epoxy resin composition, an epoxy resin composition layer was coated on the center of an aluminum foil measuring 15 cm in length, 8 cm in width, and 1.7 mm in thickness to a length of 12 cm, a width of 5 cm, and a dry film thickness of 150 μm. The coating was then dried by heating in an oven preheated to 120°C for 5 minutes to obtain a film. The dried film was allowed to cool to room temperature and then cured in an oven at 150°C for Examples 1 to 6 and Comparative Examples 1 and 2 for 1 hour with the four corners fixed with heat-resistant tape, or in an oven at 180°C for the other Examples and Comparative Examples to obtain a cured product layer. If the cured cured product layer was free of tack on the surface and cross section and had a uniform cured product layer with no areas of different color tone, the curing property was evaluated as good and marked with a circle.

[0184] (Warp Evaluation: Measurement of Warp Amount) Using the prepared epoxy resin composition, an epoxy resin composition layer was applied to the center of an aluminum foil measuring 15 cm in length, 8 cm in width, and 1.7 mm in thickness, to a length of 12 cm, a width of 5 cm, and a dry film thickness of 150 μm. The coating was then dried in an oven preheated to 120°C for 5 minutes to obtain a film. The dried film was allowed to cool to room temperature, and then cured in an oven at 150°C for Examples 1 to 6 and Comparative Examples 1 and 2 for 1 hour with the four corners secured with heat-resistant tape, or in an oven at 180°C for the other Examples and Comparative Examples to obtain a cured product. One end of the cured aluminum foil was fixed to a flat surface along its long side, and the height of the aluminum foil end on the opposite side lifted from the flat surface was measured to determine the amount of warp. Evaluation was based on the following criteria depending on the amount of warp. <Evaluation criteria> Warpage ≦ 5 mm... ◎◎ 5 mm < warpage ≦ 10 mm... ◎ 10 mm < warpage ≦ 25 mm... ◯ 25 mm < warpage... ×

[0185] (Evaluation of Heat Resistance: Measurement of Film Glass Transition Temperature) An epoxy resin composition was cured by the method described above (Evaluation of Warpage) to obtain a cured product, and then the aluminum foil was peeled off to remove the cured product layer. The removed cured product layer was subjected to DMA measurement (RSA-G2, manufactured by TA Instruments, Inc.) at a temperature rise rate of 4°C / min from 25°C to 250°C, and the temperature at which tan δ took a maximum value was taken as the glass transition temperature. A film glass transition temperature of 160°C or higher was considered to have good heat resistance.

[0186] (Evaluation of Strength: Measurement of Film Tensile Strength) The epoxy resin composition was cured by the method described above in (Evaluation of Warpage) to obtain a cured product, and then the aluminum foil was peeled off to remove the cured product layer. The removed cured product layer was cut into a width of 5 mm and a length of 4 cm to obtain a test piece. The cut test piece was subjected to a tensile test (AUTOGRAPH AGS-X 5kN, manufactured by Shimadzu Corporation) at a tension rate of 100 mm / min in a constant temperature and humidity chamber at 23°C and 50% RH, and the tensile strength was calculated from the break point.

[0187] [Component Description] The components used in the epoxy resin compositions of the Examples and Comparative Examples are shown in Tables 1 to 3 below.

[0188] (Component (A): Epoxy resin) A-1: ​​EXA850CRP (BisA type liquid epoxy resin, epoxy equivalent 190 g / eq, manufactured by DIC Corporation) A-2: EXA830CRP (BisF type liquid epoxy resin, epoxy equivalent 160 g / eq, manufactured by DIC Corporation) A-3: HP4032D (naphthalene type liquid epoxy resin, epoxy equivalent 142 g / eq, manufactured by DIC Corporation) A-4: NC-3000 (biphenyl type solid epoxy resin, epoxy equivalent 275 g / eq, manufactured by Nippon Kayaku Co., Ltd.) A-5: YX4000 (biphenyl type solid epoxy resin, epoxy equivalent 186 g / eq, manufactured by Mitsubishi Chemical Corporation) A-6: HP-4710 (naphthalene-type tetrafunctional solid epoxy resin, epoxy equivalent 170 g / eq, manufactured by DIC Corporation)

[0189] (Component (B): Specific curing agent) B-1: HPC-8000-65T (active ester curing agent, 65% solids, toluene solution, active group equivalent: 223 g / eq, manufactured by DIC Corporation) B-2: LA-3018-50P (triazine skeleton-containing phenolic curing agent, 50% solids, 1-methoxy-2-propanol solution, OH group equivalent: 151 g / eq, manufactured by DIC Corporation) B-3: CYTESTER (registered trademark) TA (bisphenol A-type cyanate ester curing agent, active group equivalent: 139 g / eq, manufactured by Mitsubishi Gas Chemical Company, Inc.)

[0190] (Component (C): Compounds represented by general formula (1) and general formula (2)) C-1: 2-(2-hydroxyphenyl)imidazole (manufactured by Ambeed, Inc.) C-2: 2-(2-hydroxyphenyl)benzimidazole (manufactured by Tokyo Chemical Industry Co., Ltd.) C-3: 2-(2-hydroxyphenyl-5-methoxyphenyl)benzimidazole (manufactured by AOBChemUSA) C-4: 2-(2-hydroxyphenyl)benzimidazole-6-carboxylic acid (manufactured by Apollo Scientific Ltd.)

[0191] (Comparative compounds not corresponding to component (C)) R-1: DMAP (4-dimethylaminopyridine, manufactured by Tokyo Chemical Industry Co., Ltd.) R-2: 1B2PZ (1-benzyl-2-phenylimidazole, manufactured by Shikoku Chemical Holdings Co., Ltd.) R-3: 2P4MZ (2-phenyl-4-methylimidazole, manufactured by Shikoku Chemical Holdings Co., Ltd.) R-4: 2MZ-A (2,4-diamino-6-[2-(2-methyl-1-imidazolyl)ethyl]-1,3,5-triazine, manufactured by Shikoku Chemical Holdings Co., Ltd.)

[0192] (Component (D): Filler) D-1: SO-E2 (spherical silica filler, average particle size 0.5 μm, manufactured by Admatechs Co., Ltd.)

[0193] (Component (E): Solvent) E-1: Methyl ethyl ketone (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) E-2: Cyclohexanone (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)

[0194] (Component (F): Other curing agents) F-1: HF-1M (phenol novolac resin curing agent, OH group equivalent 106 g / eq, manufactured by UBE)

[0195] (Component (G): Thermoplastic resin) G-1: PKHB (phenoxy resin, weight average molecular weight 32,000, manufactured by Gabriel Phenoxies)

[0196] (Component (H): Silane coupling agent) H-1: KBM-573 (aminosilane coupling agent, manufactured by Shin-Etsu Chemical Co., Ltd.)

[0197] [Examples 1 to 22], [Comparative Examples 1 to 7] Epoxy resin compositions were prepared by the above-mentioned method by blending the components in the proportions (parts by mass) shown in Tables 1 to 3. The properties of the prepared epoxy resin compositions were measured and evaluated by the above-mentioned methods.

[0198]

[0199]

[0200]

[0201] Comparing Examples 1 to 6, which used a triazine skeleton-containing phenolic curing agent as component (B), with Comparative Examples 1 and 2, it was found that the inclusion of component (C) resulted in high varnish storage stability and low warpage, and the glass transition temperature was approximately 20 to 30°C higher, demonstrating excellent results. Furthermore, comparing Examples 1 and 2 with Comparative Example 1, and Examples 3 to 6 with Comparative Example 2, which used the same curing agent type and blending amount, it was found that the Examples exhibited higher tensile strength. Examples 7 to 15, which used only an active ester curing agent or a triazine skeleton-containing phenolic curing agent as component (B), exhibited warpage approximately 20 mm smaller, glass transition temperatures approximately 10 to 30°C higher, and tensile strengths up to 28 MPa higher than Comparative Examples 3 to 5, which had the same blending system, demonstrating significantly better warpage, heat resistance, and strength. Furthermore, it was found that the varnish storage stability was also excellent. Comparing Examples 16-22 and Comparative Examples 6 and 7, which used a cyanate ester curing agent and a triazine skeleton-containing phenolic curing agent or an active ester curing agent as component (B), all had glass transition temperatures of 160°C or higher, which presented practical problems. However, the varnish storage stability of Comparative Examples 6 and 7 was extremely poor and impractical. On the other hand, it was found that the use of component (C) dramatically improved the varnish storage stability. Furthermore, comparing Examples 16-20 and Comparative Example 6, and Examples 21 and 22 and Comparative Example 7, which have the same formulation, it was found that the Examples were superior in terms of warpage and film tensile strength. These results demonstrate that the Examples containing component (C) in combination with a specific curing agent (B) were able to achieve excellent varnish storage stability, warpage, glass transition temperature, and tensile strength, demonstrating exceptional effects.

[0202] This application is based on a Japanese patent application (Patent Application No. 2023-109093) filed with the Japan Patent Office on July 3, 2023, the contents of which are incorporated herein by reference.

[0203] The epoxy resin composition of the present embodiment, while achieving both stability and reactivity, also exhibits excellent properties such as low warpage, high heat resistance, and high strength. Therefore, it has industrial applicability in the fields of: sealing materials for electrical and electronic components such as relay sealing materials; paste materials such as various insulating liquid adhesives, die attach pastes, conductive pastes, and thermally conductive pastes; ink materials such as solder resist inks and hole-filling inks; matrix resins for fiber-reinforced plastics; and resin materials such as impregnating and fixing materials for motor coils; and film materials such as interlayer insulating films, film-type solder resists, sealing sheets for semiconductor packages, die attach films, conductive films, anisotropically conductive films, non-conductive films, and thermally conductive films. In particular, multilayer printed wiring boards, coreless substrates, and large package substrates for high-speed servers and network servers require even greater low warpage, high heat resistance, and high strength, and therefore the film-type adhesive, printed wiring boards, semiconductor chip packages, electronic devices, and the like of the present invention can be effectively used.

Claims

1. An epoxy resin composition comprising: component (A): an epoxy resin; component (B): at least one curing agent selected from the group consisting of a triazine skeleton-containing phenolic curing agent, an active ester curing agent, and a cyanate ester curing agent; and component (C): a compound represented by the following formula (1) and / or a compound represented by the following formula (2). (In formulas (1) and (2), R １ , R ２ R is independently any one selected from the group consisting of a hydrogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, a halogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, and a cycloalkyl group having 6 to 20 carbon atoms which may have a substituent. １ , R ２ may be the same or different, R １ , R ２ may be bonded to form a condensed ring having no aromaticity. X is any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aralkyl group having 7 to 20 carbon atoms which may have a substituent, and a heteroarylalkyl group having 4 to 20 carbon atoms which may have a substituent. Y and Z are any one selected from the group consisting of a hydrogen atom, a halogen atom, a hydroxyl group, a carboxy group, a cyano group, a nitro group, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an alkoxy group having 1 to 20 carbon atoms which may have a substituent, an alkenyl group having 2 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 20 carbon atoms which may have a substituent, an aryloxy group having 6 to 20 carbon atoms which may have a substituent, and an acyl group having 1 to 20 carbon atoms which may have a substituent. Y and Z may be the same or different, and two or more Ys and two or more Zs may be bonded to form a monocyclic ring or a condensed ring. m and n are integers from 1 to 4.

2. The epoxy resin composition according to claim 1, further comprising component (D): a filler.

3. The epoxy resin composition according to claim 1, wherein in said component (C), Y and Z are one selected from the group consisting of a hydrogen atom, a hydroxyl group, a carboxy group, an unsubstituted alkoxy group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent, an alkoxy group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent, an aryl group having 6 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent, an aryloxy group having 6 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent, and an acyl group having 1 to 20 carbon atoms and having a hydroxyl group and / or a carboxy group as a substituent.

4. In the component (C), the compound represented by the formula (1) is any one selected from the group consisting of 2-(2-hydroxyphenyl)imidazole, 2-(2-hydroxyphenyl)-4(5)-methylimidazole, 4-ethyl-(2-hydroxyphenyl)-5-methylimidazole, (2-hydroxyphenyl)-4-isopropyl-5-methylimidazole, 4-butyl-(2-hydroxyphenyl)-5-methylimidazole, and 2-(2-hydroxy-3(5)-methoxyphenyl)imidazole, and / or the compound represented by the formula (2) is any one selected from the group consisting of 2-(2-hydroxyphenyl)imidazole, 2-(2-hydroxyphenyl)-4(5)-methylimidazole, 4-ethyl-(2-hydroxyphenyl)-5-methylimidazole, 4-butyl-(2-hydroxyphenyl)-5-methylimidazole, and 2-(2-hydroxy-3(5)-methoxyphenyl)imidazole. The epoxy resin composition according to claim 1, which is any one selected from the group consisting of 2-(2-hydroxyphenyl)benzimidazole, 2-(2-hydroxy-3(5)-methoxyphenyl)benzimidazole, 2-(1-hydroxynaphthalen-2-yl)benzimidazole, 2-(2-hydroxynaphthalen-1-yl)benzimidazole, and 2-(2-hydroxyphenyl)benzimidazole-6-carboxylic acid.

5. The epoxy resin composition according to claim 4, further comprising component (D): a filler.

6. A resin paste comprising the epoxy resin composition according to any one of claims 1 to 5.

7. A film-type adhesive comprising: a support; and a resin layer on the support, the resin layer comprising the epoxy resin composition according to any one of claims 1 to 5.

8. A film-type adhesive comprising: a support; a resin layer comprising the epoxy resin composition according to any one of claims 1 to 5 on said support; and a protective layer on said resin layer.

9. A printed wiring board having a cured layer of the epoxy resin composition according to any one of claims 1 to 5.

10. A semiconductor chip package having a cured layer of the epoxy resin composition according to any one of claims 1 to 5.

11. An electronic device comprising the printed wiring board according to claim 9.

12. An electronic device comprising the semiconductor chip package of claim 10.

Images