Epoxy resin composition and uses of same

Abstract

The present invention provides an epoxy resin composition which has excellent storage stability and cured product properties although the epoxy resin composition can be cured at a low temperature in a short time. The epoxy resin composition comprises (A) an epoxy resin that has two or more epoxy groups in each molecule, (B) an aromatic amine curing agent, (C) a gallium chelate compound, and (D) one or more organosilicon compounds that are selected from among silane compounds represented by formula (1) (wherein R1 represents an alkyl group having 1 to 4 carbon atoms, and n represents an integer of 1 to 3) and partial hydrolysis products thereof. The mass ratio (C) / (D) of the component (C) to the component (D) is 1 / 1 to 1 / 30.

Description

Epoxy Resin Composition and Its Use

[0001] The present invention relates to an epoxy resin composition and its use, preferably to an epoxy resin composition that is liquid at 25°C and its use.

[0002] Epoxy resins are used in a wide range of fields such as electronic components, adhesives, and paints. Since their properties and curing conditions vary depending on the type of curing agent, they are used in combination with various curing agents according to the application. Main curing agents include amines, acid anhydrides, phenols, etc. Among them, aromatic amine curing agents have the characteristic of obtaining a cured product with good balance such as adhesiveness and heat resistance, but have the drawback of requiring curing at high temperatures.

[0003] In recent years, attention has been focused on product development in line with SDGs, and shortening the curing time or low-temperature curability of epoxy resins has been demanded for energy conservation. To enhance curability, it is common to add a curing accelerator to the epoxy resin composition.

[0004] As a curing accelerator for epoxy resins, for example, a composite catalyst of a metal complex and a silane compound has been proposed. Since these composite catalysts do not remain as ionic impurities after acting on the curing of epoxy resins, they can prevent migration in the cured product while accelerating the curing rate (Patent Documents 1 to 4).

[0005] JP-A-2015-187209 JP-A-2015-189825 JP-A-2008-255178 JP-A-2012-117033

[0006] However, by adding a curing accelerator to the epoxy resin composition, the reaction tends to proceed even at room temperature, causing thickening. This thickening shortens the pot life of the epoxy resin. From this, it can be said that the improvement of reactivity and the thickening of the composition are in a trade-off relationship, and it has been difficult to produce an epoxy resin composition having both characteristics.

[0007] Therefore, an object of the present invention is to provide an epoxy resin composition that is excellent in storage stability and cured physical properties despite being curable at low temperature and in a short time.

[0008] In view of these circumstances, the inventors conducted diligent research and found that the aforementioned problems can be solved by adding a gallium chelate compound and a silane compound to an epoxy resin composition containing an epoxy resin and an aromatic amine curing agent, thus completing the present invention. That is, the present invention provides the following epoxy resin composition and its uses.

[0009] [1] (A) an epoxy resin having two or more epoxy groups in one molecule, (B) an aromatic amine curing agent: in an amount such that the ratio of the number of moles of amino groups in component (B) to the number of moles of epoxy groups in component (A) is 0.8 to 1.2, (C) a gallium chelate compound: 0.05 parts by mass or more and less than 1.0 parts by mass per 100 parts by mass of the total of components (A) and (B), and (D) the following formula (1) (In the formula, R 1 [1] The epoxy resin composition comprising: (A) an alkyl group having 1 to 4 carbon atoms, and n an integer from 1 to 3 carbon atoms; (B) an alkyl group having 1 to 4 carbon atoms, and n an integer from 1 to 3 carbon atoms; (C) an alkyl group having 1 to 4 carbon atoms, and n an integer from 1 to 3 carbon atoms; (D) an alkyl group having 1 to 4 carbon atoms; (N) an alkyl group having 1 to 4 carbon atoms; (N) an alkyl group having 1 to 3 carbon atoms; (D3 carbon atoms; (N) an alkyl group having 1 to 4 carbon atoms; (D) an alkyl group having 1 to 3 carbon atoms; (N) an alkyl group having 1 to 3 carbon atoms; (D) an alkyl group having 1 to 4 carbon atoms; (N) an alkyl group having 1 to 3 carbon atoms; (D) an alkyl group having 1 to 3 carbon atoms; (D) an alkyl group having 1 to 4 carbon atoms; (N) an alkyl group having 1 to 3 carbon atoms; (D) an alkyl group having 1 to 3 carbon atoms; (D) an alkyl group having 1 to 4 carbon atoms; (N) an alkyl group having 1 to 3 carbon atoms; (D) an alkyl group having 1 to 4 carbon (In equations (2) and (3), R 2(The C1 is independently an alkoxy group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms.) [5] The epoxy resin composition according to any one of [1] to [4], wherein the (C) component is gallium(III) acetylacetonate. [6] A potting agent containing the epoxy resin composition according to any one of [1] to [5]. [7] A power module sealed with the potting agent according to [6]. [8] An underfill agent containing the epoxy resin composition according to any one of [1] to [5]. [9] A flip-chip package sealed with the underfill agent according to [8].

[10] An epoxy resin adhesive containing the epoxy resin composition according to any one of [1] to [5].

[11] A semiconductor device using the epoxy resin adhesive according to

[10] .

[0010] The epoxy resin composition of the present invention has a long pot life, thus suppressing thickening even when stored at room temperature (25±5°C), and can be cured in a short time or at low temperatures, providing a cured product with good mechanical properties.

[0011] The present invention will be described in detail below. [(A) Epoxy Resin] In the present invention, the epoxy resin of component (A) is used as the main component of the epoxy resin composition. The epoxy resin has two or more epoxy groups in one molecule, preferably three or more, and its properties at 25°C may be solid or liquid, but it is preferable to be liquid in terms of handling. Component (A) may be used alone or in combination of two or more, but when using a solid epoxy resin, it is preferable to use it in combination with a liquid epoxy resin. In this case, the blending ratio of the solid epoxy resin should be 1 to 30% by mass, preferably 5 to 20% by mass, of the total mass of component (A). This improves handling and also improves the heat resistance of the cured product. Component (A) preferably has a viscosity of 3,000 to 10,000 mPa·s at 25°C. This viscosity is measured using a B-type viscometer in accordance with JIS K 7117-1:1999.

[0012] Examples of epoxy resins that are liquid at 25°C include liquid bisphenol A type epoxy resin, liquid bisphenol F type epoxy resin, liquid naphthalene type epoxy resin, liquid aminophenol type epoxy resin, liquid hydrogenated bisphenol type epoxy resin, liquid alcohol ether type epoxy resin, liquid fluorene type epoxy resin, and liquid alicyclic epoxy resin. Among these, liquid bisphenol A type epoxy resin, liquid bisphenol F type epoxy resin, liquid naphthalene type epoxy resin, and liquid aminophenol type epoxy resin are preferred.

[0013] Examples of epoxy resins that are solid at 25°C include biphenol-type epoxy resins such as 3,3',5,5'-tetramethyl-4,4'-biphenol-type epoxy resins and 4,4'-biphenol-type epoxy resins, phenol novolac-type epoxy resins, cresol novolac-type epoxy resins, bisphenol A novolac-type epoxy resins, stilbene-type epoxy resins, triazine skeleton-containing epoxy resins, fluorene skeleton-containing epoxy resins, trisphenol alkane-type epoxy resins, biphenyl-type epoxy resins, xylylene-type epoxy resins, biphenyl aralkyl-type epoxy resins, naphthalene-type epoxy resins, dicyclopentadiene-type epoxy resins, alicyclic epoxy resins, silicone-modified epoxy resins, diglycidyl ether compounds of polycyclic aromatics such as polyfunctional phenols and anthracenes, and phosphorus-containing epoxy resins obtained by introducing phosphorus compounds into these.

[0014] The epoxy equivalent of component (A) is not particularly limited, but is, for example, 80 to 200, preferably 90 to 180.

[0015] When the inorganic filler described in (E) below is not included, the amount of component (A) is preferably 1 to 90% by mass, more preferably 10 to 80% by mass, and even more preferably 20 to 70% by mass, based on the total mass of the epoxy resin composition. When the inorganic filler described in (E) below is included, the amount of component (A) is preferably 1 to 40% by mass, more preferably 5 to 30% by mass, and even more preferably 5 to 20% by mass, based on the total mass of the epoxy resin composition.

[0016] [(B) Aromatic Amine Curing Agent] In the present invention, the aromatic amine curing agent of component (B) is used as a curing agent that reacts with component (A). Component (B) may be one or more types appropriately selected from conventionally known aromatic amine curing agents. The properties of component (B) at 25°C may be solid or liquid, but a liquid state is preferable in terms of handling and other factors. Component (B) may be used alone or in combination of two or more types, but when using a solid aromatic amine curing agent, it is preferable to use it in combination with a liquid aromatic amine curing agent. This improves workability and also improves the heat resistance of the cured product.

[0017] The amount of aromatic amine curing agent added is such that the ratio of moles of amino groups in component (B) to moles of epoxy groups in component (A) is 0.8 to 1.2, preferably 0.9 to 1.1. If the molar ratio exceeds this preferred range, the cured material properties may be impaired.

[0018] Examples of aromatic amine curing agents that are liquid at 25°C include 3,3'-diethyl-4,4'-diaminodiphenylmethane, 2,4-diamino-3,5-diethyltoluene, 2,6-diamino-3,5-diethyltoluene, and dimethylthiotoluenediamine. Among these, 3,3'-diethyl-4,4'-diaminodiphenylmethane is preferred.

[0019] Examples of aromatic amine curing agents that are solid at 25°C include 4,4'-methylenebis(2-ethyl-6-methylaniline), 2,2'-diisopropyl-6,6'-dimethyl-4,4'-methylenedianiline, 2,2',6,6'-tetraisopropyl-4,4'-methylenedianiline, 4,4'-methylenebis(2,6-diethylaniline), 4,4'-methylenebis(3-chloro-2,6-diethylaniline), 1,3-phenylenediamine, and 2,4-dia Examples include minotoluene, 2,6-diaminotoluene, 2,4,6-trimethyl-1,3-phenylenediamine, 3-aminobiphenyl, 3-amino-4-methoxybiphenyl, 2-aminofluorene, 2-amino-9-fluorenone, 2,7-diaminofluorene, 3-aminobenzophenone, 3,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4-diaminobenzophenone, and 3,3'-diaminobenzophenone. Among these, 4,4'-methylenebis(2-ethyl-6-methylaniline) is preferred.

[0020] [(C) Gallium Chelate Compound] In the present invention, the gallium chelate compound of component (C) is a catalytic component that promotes the curing of epoxy resin when used in combination with the organosilicon compound of component (D), which will be described later. Component (C) is preferably a compound in which a diketonate ligand and an o-carbonylphenolate ligand are coordinated to gallium, as shown in formula (2) or (3) below.

[0021] In equations (2) and (3), R 2 These are independently alkoxy groups having 1 to 4 carbon atoms or alkyl groups having 1 to 4 carbon atoms.

[0022] In equation (2) or (3), R 2 These are independently alkoxy groups having 1 to 4 carbon atoms or alkyl groups having 1 to 4 carbon atoms. Examples of alkoxy groups include methoxy groups and ethoxy groups, while examples of alkyl groups include methyl groups and ethyl groups.

[0023] As the gallium chelate compound of component (C), gallium(III) acetylacetonate is particularly preferred. The amount of component (C) is preferably 0.05 parts by mass or more and less than 1.0 part by mass, more preferably 0.05 parts by mass or more and 0.8 parts by mass or less, and more preferably 0.1 parts by mass or more and 0.5 parts by mass or less, relative to 100 parts by mass of the total amount of components (A) and (B).

[0024] [(D) Organosilicon compound] Component (D) of the present invention is a catalytic component that promotes the curing of epoxy resin when used in combination with component (C) above.

[0025] Component (D) is one or more organosilicon compounds selected from the silane compounds or their partial hydrolysates shown in formula (1) below. In the formula, R 1 R is an alkyl group having 1 to 4 carbon atoms, and n is an integer from 1 to 3. In this invention, a partially hydrolyzed condensate is an oligomer formed when a portion of the alkoxysilyl groups of the silane compound of formula (1) is hydrolyzed and condensed with other silane compounds. Preferably, the oligomer is a hydrolyzed condensate with a degree of polymerization of 5 or less. In formula (1), R 1 n is an alkyl group having 1 to 4 carbon atoms, such as a methyl group, ethyl group, or isopropyl group. A methyl group is preferred among these. n is an integer from 1 to 3. From the viewpoint of reactivity and improving pot life, n is preferably 2 or 3, and n=2 is more preferred.

[0026] Examples of component (D) include diphenyldimethoxysilane, diphenyldiethoxysilane, diphenyldiisopropoxysilane, and methoxytriphenylsilane. These may be used individually or in combination of two or more. Diphenyldimethoxysilane is more preferred. These alkoxysilane compounds may also be partially hydrolyzed condensates. The partially hydrolyzed condensates are preferably oligomers with a degree of polymerization of 5 or less.

[0027] The amount of component (D) is 0.1 parts by mass or more and 5.0 parts by mass or less, preferably 0.5 to 3.0 parts by mass, more preferably 0.8 to 2.5 parts by mass, and even more preferably 1.0 to 2.0 parts by mass, based on 100 parts by mass of the total of components (A) and (B).

[0028] The mechanism of action of the composite catalyst in the present invention is described below. In the present invention, by using two components, (C) a gallium chelate compound and (D) an organosilicon compound having a phenyl group, in combination with an epoxy resin composition, these components act as a composite catalyst on the epoxy resin to promote curing. At this time, because the substituent of (D) the organosilicon compound is a bulky phenyl group, its interaction with (C) the gallium chelate compound is suppressed at room temperature. However, by heating during curing, the thermal motion of each component becomes more active, making it easier for (C) the gallium chelate compound and (D) the organosilicon compound to interact. The composite formed by the interaction of the two components has improved catalytic activity as a Brønsted acid due to the electron delocalization of the phenyl group. Through the above mechanism of action of the two components, both pot life and curability can be imparted to the epoxy resin composition of the present invention.

[0029] The mass ratio of component (C) to component (D) in the epoxy resin composition of the present invention is (C) / (D) = 1 / 1 to 1 / 30, preferably 1 / 1.5 to 1 / 20, and more preferably 1 / 2 to 1 / 10. Outside this range, it becomes difficult to achieve both pot life and curability.

[0030] [(E) Inorganic filler] The epoxy resin composition of the present invention may also contain (E) an inorganic filler in addition to the above components (A) to (D) for the purpose of reducing the coefficient of thermal expansion and improving moisture resistance and heat resistance reliability.

[0031] (E) Examples of inorganic fillers include silicas such as fused silica, crystalline silica, and cristobalite, alumina, silicon nitride, aluminum nitride, boron nitride, titanium oxide, glass fiber, and magnesium oxide. These may be used individually or in combination of two or more. The average particle size and shape of these inorganic fillers can be selected according to the application. Spherical alumina, spherical fused silica, and glass fiber are particularly preferred. For example, the average particle size of the inorganic filler is preferably 1 to 100 μm, more preferably 5 to 90 μm, and even more preferably 10 to 80 μm. Here, the average particle size is the 50% cumulative distribution diameter based on volume, measured by dynamic light scattering using laser light.

[0032] Alternatively, (E) inorganic fillers pre-treated with a silane coupling agent may be used. Examples of silane coupling agents for treatment include aminosilane coupling agents, epoxysilane coupling agents, vinylsilane coupling agents, methacrylicsilane coupling agents, acrylicsilane coupling agents, mercaptosilane coupling agents, triazine functional group type silane coupling agents, isocyanate functional group type silane coupling agents, isocyanuric acid functional group type silane coupling agents, benzotriazole functional group type silane coupling agents, acid anhydride functional group type silane coupling agents, azasilacyclopentane functional group type silane coupling agents, imidazole functional group type silane coupling agents, and unsaturated group-containing silane coupling agents.

[0033] (E) The amount of silane coupling agent added to the inorganic filler is not particularly limited. (E) The method for surface treating the inorganic filler with the silane coupling agent can be carried out according to conventional methods.

[0034] The amount of component (E) is 10 parts by mass or more and 1,000 parts by mass or less, preferably 100 to 750 parts by mass, and more preferably 200 to 500 parts by mass, relative to 100 parts by mass of the total of components (A) and (B).

[0035] [Other Additives] In addition to components (A) to (E) above, the epoxy resin composition of the present invention may contain other additives as needed, provided that they do not impair the purpose and effects of the present invention. Examples of additives include colorants, flame retardants, antioxidants, adhesion aids, stress reducers, and defoamers. The amount of other additives will vary depending on the intended use of the epoxy resin composition of the present invention. It should be adjusted as appropriate, provided that it does not impair the effects of the present invention. For example, the total amount of other additives may be 5% by mass or less of the total epoxy resin composition.

[0036] When storing the epoxy resin composition of the present invention at room temperature, it may be stored in two separate components. In this case, the main component is component (A) and optionally component (E), and the curing agent is component (B) and optionally component (E). Components (C) and (D) may be added to either the main component or the curing agent. That is, the present invention is preferably a two-component kit for obtaining an epoxy resin composition, comprising a first agent (resin component) containing component (A) and optionally a portion of component (E), and a second agent (curing agent component) containing component (B) and optionally the remainder of component (E), wherein components (C) and (D), and optional other components are included in either or both of the first and second agents. The mixing ratio of the first agent (resin component) and the second agent (curing agent component) should be such that the amount of components (A) to (D) or (A) to (E) in the whole composition satisfies the above-mentioned range.

[0037] The epoxy resin composition of the present invention is preferably liquid at 25°C. The epoxy resin composition has a viscosity of 10 to 500 Pa·s at 25°C, preferably 20 to 400 Pa·s, and more preferably 30 to 300 Pa·s. The viscosity is measured at 25°C using a rotational viscometer in accordance with JIS Z 8803:2011.

[0038] [Method for Producing Epoxy Resin Composition] The method for producing the epoxy resin composition of the present invention is not particularly limited. For example, the composition can be obtained by mixing, stirring, dissolving, and / or dispersing the components (A) to (D) or the components (A) to (E) while performing heat treatment simultaneously or separately as necessary. The apparatus for mixing, stirring, and dispersing in the production method is not particularly limited. For example, a kneader equipped with a stirring and heating device, a two-roll mill, a three-roll mill, a ball mill, a planetary mixer, or a mascoloider can be used, and these apparatuses can be used in appropriate combination.

[0039] [Method for Using Epoxy Resin Composition] A general epoxy resin composition can be cured, for example, at 150 to 200°C for 1 to 10 hours. However, although the epoxy resin composition of the present invention can be cured under the curing conditions of the above general epoxy resin composition, it can be cured well at a lower temperature and in a shorter time. The epoxy resin composition of the present invention can be cured, for example, by heating at a temperature of 60 to 200°C, preferably 80 to 180°C, for 30 minutes to 10 hours, preferably 1 to 5 hours. From the perspective of energy saving, for example, it is preferably cured under the conditions of a temperature of 100 to 150°C, preferably 100 to 120°C, for 1 to 2 hours.

[0040] The present invention further provides a potting agent containing the epoxy resin composition. The blending ratio of the epoxy resin composition contained in the potting agent may follow that of a conventionally known potting agent. The present invention provides a power module sealed with the potting agent. The method for sealing the power module with the potting agent is not particularly limited.

[0041] The present invention further provides an underfill agent containing the epoxy resin composition. The blending ratio of the epoxy resin composition contained in the underfill agent may follow that of a conventionally known underfill agent. The present invention provides a flip chip package sealed with the underfill agent. The method for sealing the chip with the underfill agent is not particularly limited.

[0042] The present invention further provides an epoxy resin adhesive containing the above epoxy resin composition. The blending ratio of the epoxy resin composition contained in the adhesive may follow that of a conventionally well-known epoxy resin adhesive. The present invention provides a semiconductor device having a layer made of the above adhesive. The manufacturing method of the semiconductor device is not particularly limited.

[0043] Hereinafter, examples and comparative examples will be shown to explain the present invention in more detail, but the present invention is not limited to the following examples.

[0044] [Examples 1 to 8 and Comparative Examples 1 to 6] Each of the components shown below was mixed at 25°C with the compositions shown in Tables 1 and 2 to obtain an epoxy resin composition.

[0045] (A) Epoxy resin Epoxy resin (A1) that is liquid at 25°C: Bisphenol A type epoxy resin (YD-8125: manufactured by Nippon Steel Chemical & Material Co., Ltd.) Epoxy resin (A2) that is liquid at 25°C: Aminophenol type trifunctional epoxy resin (jER630: manufactured by Mitsubishi Chemical Corporation) Silicone-modified epoxy resin (A3) Into a 1-liter four-necked flask equipped with a reflux condenser, a thermometer, a stirrer, and a dropping funnel, the following formula (4) 200 g of a phenol novolak resin (phenol equivalent 125, allyl equivalent 1,100) modified with allyl glycidyl ether represented by, 800 g of chloromethyloxirane, and 0.6 g of cetyltrimethylammonium bromide were each added and heated, and stirred and mixed at a temperature of 110°C for 3 hours. This was cooled to a temperature of 70°C, depressurized to 160 mmHg, and then 128 g of a 50% aqueous solution of sodium hydroxide was added dropwise thereto over 3 hours while performing azeotropic dehydration. The obtained content was depressurized to distill off the solvent, then dissolved in a mixed solvent of 300 g of methyl isobutyl ketone and 300 g of acetone, washed with water, and the solvent was distilled off under reduced pressure to obtain an allyl group-containing epoxy resin (allyl equivalent 1590, epoxy equivalent 190) represented by the following formula (5) 170 g of methyl isobutyl ketone, 330 g of toluene, and 0.07 g of a 2-ethylhexanol-modified chloroplatinic acid solution with a platinum concentration of 2% by mass were added to this epoxy resin, and azeotropic dehydration was performed for 1 hour, and at the reflux temperature, the following formula (6) ed 133 g of organopolysiloxane (weight-average molecular weight 8,000) represented by [formula] was added dropwise over a period of 30 minutes. The mixture was then stirred and reacted at the same temperature for 4 hours. The resulting contents were washed with water, and the solvent was removed under reduced pressure to obtain a yellowish-white opaque solid copolymer. The epoxy equivalent was 280, and the ICI melt viscosity at 150°C, measured using a cone-plate viscometer according to ASTM D4287, was 800 mPa·s, with a silicon content of 31% by mass.

[0046] (B) Amine curing agent Aromatic amine curing agent that is liquid at 25°C: 3,3'-diethyl-4,4'-diaminodiphenylmethane (Kayahard AA: manufactured by Nippon Kayaku Co., Ltd.)

[0047] (B)' Comparable curing agent: A mixture of 4-methylhexahydrophthalic anhydride and hexahydrophthalic anhydride (Ricacid MH-700: manufactured by Shin Nippon Rika Co., Ltd.)

[0048] (C) Gallium chelate compound gallium(III) acetylacetonate (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0049] (D) Organosilicon compound: Diphenyldimethoxysilane (KBM-202SS: manufactured by Shin-Etsu Chemical Co., Ltd.)

[0050] (D)'Comparative organosilicon compound: 3-glycidoxypropyltrimethoxysilane (KBM-403: manufactured by Shin-Etsu Chemical Co., Ltd.)

[0051] (E) Inorganic filler: Spherical silica with an average particle size of 15 μm, surface-treated with N-phenyl-3-aminopropyltrimethoxysilane.

[0052] Curing accelerator for comparison: Triphenylphosphinetriphenylborane (TPP-S: manufactured by Hokko Chemical Co., Ltd.)

[0053] [Evaluation] Each epoxy resin composition of Examples 1 to 8 and Comparative Examples 1 to 6 was tested using the evaluation method described below. The results are shown in Tables 1 and 2. (1) After preparing the curable epoxy resin composition, it was molded at 120°C for 60 minutes. ○ was used to indicate that a cured product could be produced, and × was used to indicate that curing was insufficient and the product broke during demolding, preventing the production of a cured product. The results are shown in Tables 1 and 2.

[0054] (2) Bending strength The bending strength of the cured material prepared under the above curing conditions was measured in accordance with JIS K 6911:2006. The results are shown in Tables 1 and 2.

[0055] (3) Flexural modulus The flexural modulus of the cured product prepared under the above curing conditions was measured in accordance with JIS K 6911:2006. The results are shown in Tables 1 and 2.

[0056] (4) Exothermic Peak Temperature The exothermic peak temperature due to the curing reaction of the epoxy resin composition was measured using a differential scanning calorimeter (DSC). 10 mg of the epoxy resin composition was placed in a 40 μl aluminum sample pan and heated from 25°C to 300°C at a heating rate of 10°C / min. The exothermic peak temperature was calculated from the peak temperature in the resulting graph. The results are shown in Tables 1 and 2.

[0057] (5) Viscosity Increase The viscosity of the epoxy resin composition at 25°C was measured using a rotational viscometer in accordance with JIS Z 8803:2011. After storage at 25°C for 12 hours, the viscosity of the epoxy resin composition was measured again, and the increase in viscosity after storage relative to the viscosity before storage (viscosity after storage / viscosity before storage) was calculated. The results are shown in Tables 1 and 2.

[0058]

[0059]

[0060] In the compositions of Comparative Examples 1, 2, and 4, the reaction was slow, and the product remained uncured at 120°C / 60 minutes. In the composition of Comparative Example 3, the reaction was too fast, and curing began immediately upon mixing, making it impossible to perform bending measurements. In the composition of Comparative Example 5, a cured product was produced, but cracks were present in the cured product, making bending measurements impossible. Furthermore, in the composition of Comparative Example 6, which was the same as Comparative Example 5 but without component (D) and with an increased amount of gallium chelate compound (C), a cured product was produced and bending measurements could be performed, but after 12 hours of storage, the viscosity increased 2.6 times from the initial viscosity, resulting in a short pot life.

Claims

1. (A) an epoxy resin having two or more epoxy groups in one molecule, (B) an aromatic amine curing agent: in an amount such that the ratio of the number of moles of amino groups in component (B) to the number of moles of epoxy groups in component (A) is 0.8 to 1.2, (C) a gallium chelate compound: 0.05 parts by mass or more and less than 1.0 parts by mass per 100 parts by mass of the total of components (A) and (B), and (D) the following formula (1) (In the formula, R 1 An epoxy resin composition comprising: a silane compound selected from the silane compounds or their partial hydrolysates shown in (A) and (B), in an amount of 0.1 parts by mass or more and 5.0 parts by mass or less per 100 parts by mass of the total of components (A) and (B), wherein the mass ratio of component (C) to component (D) is (C) / (D) = 1 / 1 to 1 / 30.

2. The epoxy resin composition according to claim 1, further comprising (E) an inorganic filler.

3. The epoxy resin composition according to claim 1, wherein both component (A) and component (B) are in liquid form.

4. The epoxy resin composition according to claim 1, wherein the component (C) has a structure represented by the following formula (2) or (3). (In formula (2) and (3), R 2 is independently an alkoxy group having 1 to 4 carbon atoms or an alkyl group having 1 to 4 carbon atoms.) 5. The epoxy resin composition according to claim 1, wherein the (C) component is gallium(III) acetylacetonate.

6. A potting agent containing the epoxy resin composition described in claim 1.

7. A power module sealed with the potting agent described in claim 6.

8. An underfill agent containing the epoxy resin composition described in claim 1.

9. A flip-chip package sealed with the underfill material described in claim 8.

10. An epoxy resin adhesive containing the epoxy resin composition described in claim 1.

11. A semiconductor device using the epoxy resin adhesive described in claim 10.

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