JPWO2018179438A1 - Epoxy resin composition, cured epoxy resin, and electronic component device - Google Patents

Abstract

An epoxy resin composition containing an epoxy resin, a curing agent, an inorganic filler, and an organic solvent having a boiling point of 50C to 100C.

Description

  The present invention relates to an epoxy resin composition, an epoxy resin cured product, and an electronic component device.

  2. Description of the Related Art Curable resins such as epoxy resins have been widely used as materials for molded articles, laminates, adhesives, various electronic and electrical components, paints, inks, and the like. In particular, epoxy resin compositions are widely used as sealing materials in the field of sealing technology for electronic components such as transistors and ICs (Integrated Circuits). The reason for this is that the epoxy resin is balanced in various properties such as moldability, electrical properties, moisture resistance, heat resistance, mechanical properties, and adhesiveness to insert products.

  On the other hand, in recent years, in the field of electronic components, higher speed and higher density have been promoted, and accordingly, the heat generation of the electronic components has been significantly increased. Demand for electronic components that operate at high temperatures is also increasing. Therefore, there is a demand for improved thermal conductivity of plastics used for electronic components, particularly cured epoxy resin.

  As a method for improving the thermal conductivity of a cured product of an epoxy resin, a method using a crystalline epoxy resin, a method of increasing a filling amount of a high thermal conductive filler in an epoxy resin composition, and the like have been reported (for example, , Patent Documents 1 to 4).

JP 2007-153969 A JP 2012-212225 A JP 2008-106126 A JP-A-11-323162

However, the methods described in the above patent documents involve an increase in the softening point of the epoxy resin or an increase in the filler filling amount, so that the flowability of the epoxy resin composition may be reduced and moldability may be impaired. Therefore, development of an epoxy resin composition that maintains high thermal conductivity after curing and has excellent fluidity is required.
An object of the present invention is to provide an epoxy resin composition having excellent fluidity, a cured epoxy resin that is a cured product of the epoxy resin composition, and an electronic component device including an element sealed with the cured epoxy resin. That is.

The present invention includes the following embodiments.
<1> An epoxy resin composition containing an epoxy resin, a curing agent, an inorganic filler, and an organic solvent having a boiling point of 50C to 100C.
<2> The epoxy resin composition according to <1>, wherein the content of the organic solvent is 0.1% by mass to 10% by mass.
<3> The epoxy resin composition according to <1> or <2>, wherein the content of the inorganic filler is 55% by mass to 95% by mass.
<4> The epoxy resin composition according to any one of <1> to <3>, further containing a coupling agent.
<5> The epoxy resin composition according to <4>, wherein the content of the coupling agent is 0.05% by mass to 5.0% by mass.
<6> An epoxy resin composition which is tablet-shaped and has a content of an organic solvent having a boiling point of 50 ° C to 100 ° C of 0.3% by mass to 3.0% by mass.

<7> A cured epoxy resin obtained by curing the epoxy resin composition according to any one of <1> to <6>.

<8> An electronic component device comprising: an element; and the epoxy resin cured product according to <7>, which seals the element.

  According to the present invention, there is provided an epoxy resin composition having excellent fluidity, an epoxy resin cured product which is a cured product of the epoxy resin composition, and an electronic component device including an element sealed with the epoxy resin cured product. be able to.

In this specification, the term "step" includes, in addition to a step independent of other steps, even if the purpose of the step is achieved even if it cannot be clearly distinguished from the other steps, the step is also included. It is.
In this specification, a numerical range indicated by using “to” indicates a range including numerical values described before and after “to” as a minimum value and a maximum value, respectively.
In the numerical ranges described in stages in this specification, the upper limit or lower limit described in one numerical range may be replaced with the upper limit or lower limit of the numerical range described in other stages. Good. Further, in the numerical ranges described in this specification, the upper limit or the lower limit of the numerical ranges may be replaced with the values shown in the embodiments.
In the present specification, the content and content of each component in the composition, when there are a plurality of types of substances corresponding to each component in the composition, unless otherwise specified, the plurality of types of the substances present in the composition It means the total content and content of the substance.
In the present specification, the particle diameter of each component in the composition, when there are a plurality of particles corresponding to each component in the composition, unless otherwise specified, a mixture of the plurality of particles present in the composition Means the value of

<Epoxy resin composition>
The epoxy resin composition according to one embodiment of the present invention contains an epoxy resin, a curing agent, an inorganic filler, and an organic solvent having a boiling point of 50C to 100C. Thereby, the epoxy resin composition of the present embodiment is excellent in fluidity.

[Epoxy resin]
The epoxy resin composition of the present embodiment contains an epoxy resin, and preferably contains an epoxy resin having two or more epoxy groups in one molecule. Examples of the epoxy resin having two or more epoxy groups in one molecule include biphenylene type epoxy resin, stilbene type epoxy resin, sulfur atom containing epoxy resin, dicyclopentadiene type epoxy resin, naphthalene type epoxy resin, salicylaldehyde type epoxy resin. And at least one selected from the group consisting of a copolymerized epoxy resin of naphthols and phenols, an aralkyl type epoxy resin, a diphenylmethane type epoxy resin and a triphenylmethane type epoxy resin (hereinafter also referred to as a specific epoxy resin). No. Among them, biphenylene type epoxy resins and diphenylmethane type epoxy resins are preferred. The epoxy resins may be used alone or in combination of two or more.

  When the epoxy resin composition contains the specific epoxy resin as the epoxy resin, another epoxy resin other than the specific epoxy resin may be further included as the epoxy resin. As other epoxy resins, there can be mentioned those usually used in the art. Specific examples include an epoxy-silica hybrid resin in which a functional group or a skeleton is modified to improve flexibility or adhesiveness, and a flexible tough liquid epoxy resin. Other epoxy resins may be used alone or in combination of two or more.

  When the epoxy resin composition contains the specific epoxy resin as the epoxy resin, the total content of the specific epoxy resin in the total amount of the epoxy resin is preferably 60% by mass or more from the viewpoint of sufficiently exhibiting the performance of the specific epoxy resin. Preferably, it is at least 75% by mass, more preferably at least 90% by mass.

  The epoxy equivalent of the epoxy resin contained in the epoxy resin composition is preferably from 90 g / eq to 500 g / eq, more preferably from 140 g / eq to 450 g / eq, and from 190 g / eq to 400 g / eq. Is more preferred.

  The epoxy equivalent of the epoxy resin is a value measured by a method according to JIS K 7236: 2009.

  The melting point or softening point of the epoxy resin is preferably from 50C to 250C, more preferably from 65C to 200C, and still more preferably from 80C to 170C.

  The melting point or softening point of the epoxy resin is a value measured by a single cylinder rotational viscometer described in JIS K 7234: 1986 and JIS K 7233: 1986.

[Curing agent]
The epoxy resin composition of the present embodiment contains a curing agent. The curing agent is not particularly limited as long as it can react with the epoxy resin. From the viewpoint of improving heat resistance, the curing agent is preferably a compound having two or more phenolic hydroxyl groups in one molecule (hereinafter, also referred to as a phenol curing agent). The phenol curing agent may be a low-molecular phenol compound or a phenol resin obtained by polymerizing a low-molecular phenol compound. From the viewpoint of thermal conductivity, the phenol curing agent is preferably a phenol resin.

  The phenol resin is selected from the group consisting of biphenylene-type phenol resin, aralkyl-type phenol resin, dicyclopentadiene-type phenol resin, copolymer resin of benzaldehyde-type phenol resin and aralkyl-type phenol resin, and triphenylmethane-type phenol resin. At least one type (hereinafter, also referred to as a specific phenol curing agent) may be used. Especially, a triphenylmethane type phenol resin is preferable. As the curing agent, one type may be used alone, or two or more types may be used in combination.

  When the epoxy resin composition contains a specific phenol curing agent as a curing agent, it may further contain other curing agents other than the specific phenol curing agent. Other curing agents include phenolic resins other than the specific phenolic curing agent commonly used in the art. Other curing agents may be used alone or in combination of two or more.

  When the epoxy resin composition contains the specific phenol curing agent as a curing agent, the content of the specific phenol curing agent in the total amount of the curing agent is 60% by mass or more from the viewpoint of sufficiently exhibiting the performance of the specific phenol curing agent. Is preferably 75% by mass or more, more preferably 90% by mass or more.

  The hydroxyl equivalent of the curing agent contained in the epoxy resin composition is preferably from 70 g / eq to 500 g / eq, more preferably from 100 g / eq to 450 g / eq, and from 150 g / eq to 400 g / eq. Is more preferred.

  The hydroxyl equivalent of the curing agent is a value measured by a method according to JIS K 0070: 1992.

  The melting point or softening point of the curing agent contained in the epoxy resin composition is preferably from 50C to 250C, more preferably from 65C to 200C, and even more preferably from 80C to 170C. .

  The melting point or softening point of the curing agent is a value measured by a single cylinder rotational viscometer described in JIS K 7234: 1986 and JIS K 7233: 1986.

  The content ratio of the epoxy resin to the curing agent in the epoxy resin composition is such that the ratio of the number of equivalents of hydroxyl groups of the curing agent to the number of equivalents of epoxy groups of the epoxy resin (equivalent number of hydroxyl groups / equivalent number of epoxy groups) is 0. It is preferably set to be in the range of 5 to 2.0, more preferably set to be in the range of 0.7 to 1.5, and set to be in the range of 0.8 to 1.3. More preferably, When the ratio is 0.5 or more, the epoxy resin is sufficiently cured, and the cured product tends to have excellent heat resistance, moisture resistance, and electrical properties. When the ratio is 2.0 or less, the amount of phenolic hydroxyl groups remaining in the cured resin is suppressed, and the electrical properties and the moisture resistance tend to be excellent.

Examples of the combination of the epoxy resin and the curing agent in the epoxy resin composition include the following.
(1) a combination in which the epoxy resin includes at least one selected from specific epoxy resins and the curing agent includes at least one selected from specific phenol curing agents; and (2) the epoxy resin includes a biphenylene-type epoxy resin, and is cured. (3) a combination in which the epoxy resin contains a diphenylmethane type epoxy resin and the curing agent contains a triphenylmethane type phenol resin

[Inorganic filler]
The epoxy resin composition of the present embodiment contains an inorganic filler. When the epoxy resin composition contains an inorganic filler, the cured product of the epoxy resin composition can be improved in thermal expansion coefficient (linear expansion coefficient), thermal conductivity, elastic modulus, and the like.

  The inorganic filler is not particularly limited, and those commonly used in epoxy resin compositions for sealing can be appropriately selected and used. As the inorganic filler, fused silica, crystalline silica, glass, alumina, calcium carbonate, zirconium silicate, magnesium oxide, calcium silicate, silicon nitride, aluminum nitride, boron nitride, silicon carbide, industrial diamond, beryllia, zirconia, Examples include inorganic particles such as zircon, fosterite, steatite, spinel, mullite, titania, talc, clay, and mica, and beads obtained by spheroidizing these particles. In addition, an inorganic filler having a flame retardant effect can be used. Examples of the inorganic filler having a flame retardant effect include particles of aluminum hydroxide, magnesium hydroxide, a composite metal hydroxide such as a composite hydroxide of magnesium and zinc, and particles of zinc borate. One kind of the inorganic filler may be used alone, or two or more kinds may be used in combination.

  Among the inorganic fillers, silica particles such as fused silica are preferred from the viewpoint of reducing the linear expansion coefficient of the cured product of the epoxy resin composition, and alumina particles are preferred from the viewpoint of improving the thermal conductivity of the cured product of the epoxy resin composition. Particles are preferred.

  The content of the inorganic filler in the epoxy resin composition is not particularly limited. The content of the inorganic filler is, for example, preferably from 55% by mass to 95% by mass, more preferably from 60% by mass to 90% by mass, based on the total mass of the epoxy resin composition. When the content of the inorganic filler is 55% by mass or more, the cured product of the epoxy resin composition tends to have excellent linear expansion coefficient, thermal conductivity, elastic modulus, and the like. When the content of the inorganic filler is 95% by mass or less, an increase in the viscosity of the epoxy resin composition is suppressed, the fluidity is excellent, and the package tends to be easily formed.

  The average particle size of the inorganic filler is not particularly limited. The average particle diameter of the inorganic filler is, for example, preferably from 0.1 μm to 80 μm, and more preferably from 0.3 μm to 50 μm. When the average particle diameter of the inorganic filler is 0.1 μm or more, the increase in the viscosity of the epoxy resin composition tends to be easily suppressed. When the average particle diameter of the inorganic filler is 80 μm or less, the mixing property between the epoxy resin composition and the inorganic filler is improved, and the state of the package obtained by curing is more homogenized, and the variation in characteristics tends to be suppressed. Yes, there is a tendency that the filling property in a narrower area is improved. The distribution of the particle diameter of the inorganic filler preferably has a maximum value in the range of 0.1 μm to 80 μm.

  In the present specification, the average particle diameter of the inorganic filler, using a dry type particle size distribution meter, or using a wet type particle size distribution measuring device in the state of a slurry in which the inorganic filler is dispersed in water or an organic solvent. Can be measured. In particular, when particles having a particle size of 1 μm or less are included, the measurement is preferably performed using a wet type particle size distribution meter. Specifically, a water slurry in which the concentration of the inorganic filler was adjusted to about 0.01% by mass was treated with a bath-type ultrasonic cleaner for 5 minutes, and a laser diffraction particle size analyzer (LA-960, Horiba, Ltd.) ) Can be determined from the average value of all the particles detected.

  From the viewpoint of the fluidity of the epoxy resin composition, the particle shape of the inorganic filler is preferably spherical rather than square, and the particle size distribution of the inorganic filler is preferably wide. For example, when the inorganic filler is contained in an amount of 55% by volume or more, 70% by mass or more thereof is formed into spherical particles, and the particle diameter of the spherical particles is preferably distributed over a wide range of 0.1 μm to 80 μm. Such an inorganic filler is easy to form a close-packed structure by mixing particles having different sizes, so even if the content of the inorganic filler is increased, an increase in the viscosity of the epoxy resin composition is suppressed, An epoxy resin composition having excellent fluidity tends to be obtained.

[Organic solvent]
The epoxy resin composition of the present embodiment contains an organic solvent having a boiling point of 50C to 100C (hereinafter, also referred to as a specific organic solvent). When the epoxy resin composition contains the specific organic solvent, the viscosity of the composition is reduced, so that the kneading property and the fluidity are improved.

  The specific organic solvent is not particularly limited, and for example, has a boiling point of 50 ° C. to 100 ° C., and preferably a non-reactive one can be appropriately selected and used as a component in the epoxy resin composition. Specific organic solvents include alcohol solvents, ether solvents, ketone solvents, ester solvents and the like. Among them, alcohol solvents are preferable, and methanol (boiling point 64.7 ° C.), ethanol (boiling point 78.37 ° C.), propanol (boiling point 97 ° C.), and isopropanol (boiling point 82.6 ° C.) are more preferable. The specific organic solvent may be used alone or in combination of two or more. The specific organic solvent may be added when preparing the epoxy resin composition, or may be generated by a reaction in a kneading process when preparing the epoxy resin composition. In addition, in this specification, the boiling point of a specific organic solvent refers to the boiling point of the specific organic solvent measured at normal pressure.

  The content of the specific organic solvent in the epoxy resin composition is not particularly limited. The content of the specific organic solvent is, for example, preferably from 0.1% by mass to 10% by mass with respect to the total mass of the epoxy resin composition, and from the viewpoint of further improving thermal conductivity, from 0.3% by mass. The amount is more preferably from 4.0 to 4.0% by mass, further preferably from 0.3 to 3.0% by mass, and particularly preferably from 0.3 to 2.5% by mass. When the content of the specific organic solvent is 0.3% by mass or more, the effect of improving the fluidity tends to be further increased. When the content of the specific organic solvent is 3.0% by mass or less, the generation of voids is more suppressed when the epoxy resin in the epoxy resin composition is cured, and the decrease in insulation reliability tends to be further suppressed. is there.

  The content of the alcohol-based solvent in the specific organic solvent is not particularly limited. The content of the alcohol-based solvent is, for example, preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, based on the total mass of the specific organic solvent. It is particularly preferred that the content be 95% by mass or more. Further, the epoxy resin composition may not substantially contain a specific organic solvent other than the alcohol-based solvent.

[Curing accelerator]
The epoxy resin composition of the present embodiment may contain a curing accelerator as needed. As the curing accelerator, those generally used in epoxy resin compositions for sealing can be appropriately selected and used. Examples of the curing accelerator include an organic phosphorus compound such as triphenylphosphine, an imidazole compound, a tertiary amine, and a quaternary ammonium salt. Among them, an organic phosphorus compound such as triphenylphosphine is preferable. The curing accelerator may be used alone or in combination of two or more.

  When the epoxy resin composition contains a curing accelerator, the content of the curing accelerator is not particularly limited, and may be, for example, 1.0% by mass to 10% by mass based on the total amount of the epoxy resin and the curing agent. Preferably, it is 1.5 mass%-7 mass%, more preferably, 2.0 mass%-6 mass%.

[Additive]
The epoxy resin composition of the present embodiment may contain additives such as an anion exchanger, a release agent, a flame retardant, a coupling agent, a stress relieving agent, and a coloring agent as needed.

(Anion exchanger)
The epoxy resin composition may contain an anion exchanger as needed. In particular, when the epoxy resin composition is used as a molding material for encapsulation, from the viewpoint of improving the moisture resistance and high-temperature storage characteristics of the electronic component device including the element to be encapsulated, it is possible to include an anion exchanger. preferable.

  The anion exchanger is not particularly limited, and can be selected from those conventionally used in the art. Examples include hydrotalcite compounds and hydrated oxides of elements selected from magnesium, aluminum, titanium, zirconium and bismuth.

The anion exchanger is not particularly limited, and can be selected from those conventionally used in the art. Examples of the anion exchanger include a hydrotalcite compound having a composition represented by the following formula (I) and a hydrated oxide of an element selected from the group consisting of magnesium, aluminum, titanium, zirconium, bismuth and antimony. . The anion exchanger may be used alone or in combination of two or more.
Mg _1-x Al _x (OH) ₂ (CO ₃ ) _{x / 2} · mH ₂ O (I)
(0 <X ≦ 0.5, m is a positive number)

Hydrotalcite compounds are trapped by replacing anions such as halogen ions with CO ₃ in the structure, and the halogen ions incorporated in the crystal structure are desorbed at about 350 ° C or higher until the crystal structure is destroyed. It is a compound with no properties. The hydrotalcite having such properties, Mg ₆ Al ₂ which is produced as a natural product _{(OH) 16 CO 3 · 4H} 2 O, Mg 4.3 Al 2 (OH) 12.6 CO 3 as synthetic products -MH ₂ O and the like.

  When the epoxy resin composition contains a phenol curing agent as a curing agent, the epoxy resin composition shows acidity under the influence of the phenol curing agent (for example, the pH of an extract of a cured product using pure water becomes 3 to 5). . In this case, for example, aluminum, which is an amphoteric metal, becomes an environment that is easily corroded by the epoxy resin composition, but the epoxy resin composition contains a hydrotalcite compound that also has an action of adsorbing an acid, thereby causing corrosion of aluminum. Tend to be suppressed.

Further, a hydrated oxide of at least one element selected from the group consisting of magnesium, aluminum, titanium, zirconium, bismuth and antimony can also be captured by replacing an anion such as a halogen ion with a hydroxide ion. These ion exchangers show excellent ion exchange capacity on the acidic side. Therefore, when these ion exchangers are contained in the epoxy resin composition, similarly to the case where the hydrotalcite compound is contained, corrosion of aluminum tends to be suppressed. The hydrous _{oxide, MgO · nH 2 O, Al} 2 O 3 · nH 2 O, ZrO 2 · H 2 O, Bi 2 O 3 · H 2 O, Sb 2 O 5 · nH 2 O , and the like.

  When the epoxy resin composition contains an anion exchanger, the content of the anion exchanger is not particularly limited as long as it is a sufficient amount to capture anions such as halogen ions. When the epoxy resin composition contains an anion exchanger, the content of the anion exchanger is, for example, preferably from 0.1% by mass to 30% by mass, and more preferably from 1.0% by mass to 5% by mass. More preferably, there is.

(Release agent)
The epoxy resin composition may optionally contain a release agent from the viewpoint of exhibiting good release properties from the mold in the molding step. The type of the release agent is not particularly limited, and examples thereof include release agents known in the art. Specifically, examples of the release agent include carnauba wax, higher fatty acids such as montanic acid and stearic acid, higher fatty acid metal salts, ester waxes such as montanic acid esters, and polyolefin waxes such as polyethylene oxide and non-oxidized polyethylene. No. Among them, carnauba wax and polyolefin wax are preferred. One type of release agent may be used alone, or two or more types may be used in combination.

  Commercial products may be used as the polyolefin-based wax, and examples thereof include low molecular weight polyethylene having a number average molecular weight of about 500 to 10,000 such as H4, PE, and PED series manufactured by Hoechst.

When the epoxy resin composition contains a polyolefin-based wax, the content of the polyolefin-based wax is preferably 0.01% by mass to 10% by mass relative to the epoxy resin, and is 0.10% by mass to 5% by mass. Is more preferable. When the content of the polyolefin wax is 0.01% by mass or more, sufficient releasability tends to be obtained, and when it is 10% by mass or less, sufficient adhesiveness tends to be obtained.
When the epoxy resin composition contains other release agents other than the polyolefin wax, or when the epoxy resin composition contains a polyolefin wax and other release agents, the content of other release agents Is preferably from 0.1% by mass to 10% by mass, more preferably from 0.5% by mass to 3% by mass, based on the epoxy resin.

(Flame retardants)
The epoxy resin composition may contain a flame retardant as necessary from the viewpoint of imparting flame retardancy. The flame retardant is not particularly limited, and examples thereof include known organic and inorganic compounds containing a halogen atom, an antimony atom, a nitrogen atom or a phosphorus atom, metal hydroxides, and acenaphthylene. The flame retardants may be used alone or in combination of two or more.

  When the epoxy resin composition contains a flame retardant, the content of the flame retardant is not particularly limited as long as the flame retardant effect can be obtained. When the epoxy resin composition contains a flame retardant, the content of the flame retardant is preferably 1% by mass to 30% by mass, more preferably 2% by mass to 15% by mass with respect to the epoxy resin. preferable.

(Coupling agent)
The epoxy resin composition may optionally contain a coupling agent from the viewpoint of increasing the adhesiveness between the resin component and the inorganic filler. The type of the coupling agent is not particularly limited. Examples of the coupling agent include various silane compounds such as epoxy silane, mercapto silane, amino silane, alkyl silane, ureido silane, methacryl silane, acryl silane, and vinyl silane, a titanium compound, an aluminum chelate compound, and a compound containing aluminum and zirconium. One type of coupling agent may be used alone, or two or more types may be used in combination.

  When the epoxy resin composition contains a coupling agent, the content of the coupling agent is preferably 0.05% by mass to 5.0% by mass, and more preferably 0.10% by mass to 5.0% by mass with respect to the inorganic filler. More preferably, it is 2.5% by mass. When the content of the coupling agent is 0.05% by mass or more, the adhesiveness to the frame tends to be improved, and when the content is 5% by mass or less, the moldability of the package tends to be excellent.

(Stress relaxation agent)
The epoxy resin composition may contain a stress relieving agent such as silicone oil or silicone rubber particles as needed from the viewpoint of reducing the amount of warpage of the package and the package crack. As a usable stress relaxing agent, a known flexible agent (stress relaxing agent) generally used in the technical field can be appropriately selected and used.

  Specific examples of the stress relaxing agent include thermoplastic elastomers such as silicone, polystyrene, polyolefin, polyurethane, polyester, polyether, polyamide, and polybutadiene; NR (natural rubber), NBR (acrylonitrile-butadiene rubber), acrylic rubber, urethane rubber Rubber particles having a core-shell structure such as methyl methacrylate-styrene-butadiene copolymer (MBS), methyl methacrylate-silicone copolymer, methyl methacrylate-butyl acrylate copolymer Particles; and the like. Among them, a silicone-based stress relieving agent containing silicone is preferable. Examples of the silicone-based stress relaxation agent include those having an epoxy group, those having an amino group, and those modified with polyether. The stress relaxation agent may be used alone or in combination of two or more.

(Colorant)
The epoxy resin composition may contain a coloring agent such as carbon black, fibrous carbon, an organic dye, an organic coloring agent, titanium oxide, lead red, and red bengal. When the epoxy resin composition contains a colorant, the content of the colorant is preferably 0.05% by mass to 5.0% by mass, and more preferably 0.10% by mass to 2.0% by mass with respect to the inorganic filler. More preferably, it is 5% by mass.

[Method of preparing epoxy resin composition]
For preparing the epoxy resin composition, any method may be used as long as various components can be dispersed and mixed. As a general method, there can be mentioned a method in which components of a predetermined compounding amount are sufficiently mixed by a mixer or the like, and then melt-kneaded by a mixing roll, an extruder, or the like, cooled, and pulverized. More specifically, the epoxy resin composition, for example, after mixing and stirring a predetermined amount of the above-described components, kneaded in a pre-heated 70 to 140 ° C., kneaded with a roll, extruder, and the like, It can be obtained by a method such as cooling and pulverizing. The epoxy resin composition may be tableted with a size and a mass that match the molding conditions of the package. The tableting of the epoxy resin composition facilitates handling. The content of the specific organic solvent in the tablet-shaped epoxy resin composition is preferably from 0.1% by mass to 10% by mass based on the total mass of the epoxy resin composition, and the thermal conductivity is further improved. In light of this, it is more preferably from 0.3% by mass to 4.0% by mass, even more preferably from 0.3% by mass to 3.0% by mass, and more preferably from 0.3% by mass to 2.5% by mass. % Is particularly preferred.

<Epoxy resin cured product>
The cured epoxy resin of the present embodiment is a cured product of the above-described epoxy resin composition. Since the epoxy resin cured product of the present embodiment is obtained by curing the above-described epoxy resin composition, it tends to have excellent thermal conductivity.

<Electronic component device>
The electronic component device of the present embodiment includes an element and a cured product of the above-described epoxy resin composition that seals the element. Examples of the electronic component device include a device in which an element such as an active element or a passive element is mounted on a support member, and the element is sealed with the above-described epoxy resin composition. Examples of the support member include a lead frame, a wired tape carrier, a wiring board, a glass plate, and a silicon wafer. Examples of the active element include a semiconductor chip, a transistor, a diode, and a thyristor. Examples of the passive element include a capacitor, a resistor, and a coil.

  More specifically, for example, after fixing a semiconductor element on a lead frame and connecting a terminal part of the element such as a bonding pad and a lead part by wire bonding or a bump, the epoxy resin composition of the above-described embodiment is used. DIP (Dual Inline Package), PLCC (Plastic Leaded Chip Carrier), QFP (Quad Flat Package), SOP (Small Outline Package), SOJ (Small Outline J-lead Package), TSOP (Thin Small Outline Package), general resin-sealed IC such as TQFP (Thin Quad Flat Package); TCP in which a semiconductor chip connected to a tape carrier by a bump is sealed with the epoxy resin composition of the above-described embodiment. (Tape Carrier Package); Wire bonding, flip chip bonding, soldering on wiring formed on wiring board or glass (Chip on board) in which active elements such as semiconductor chips, transistors, diodes, and thyristors and / or passive elements such as capacitors, resistors, and coils are connected with the epoxy resin composition of the above embodiment. Module, hybrid IC, multi-chip module; after mounting the element on the surface of the organic substrate having terminals for wiring board connection formed on the back surface, connecting the element and the wiring formed on the organic substrate by bump or wire bonding, BGA (Ball Grid Array) and CSP (Chip Size Package) in which the element is sealed with the epoxy resin composition of the above embodiment. Further, the epoxy resin composition of the above-described embodiment can be effectively used for a printed circuit board.

  In the electronic component device of the present embodiment, the method for sealing the element with the cured epoxy resin is not particularly limited, and a method known in the art can be applied. For example, a low pressure transfer molding method is generally used, but an injection molding method, a compression molding method, or the like may be used.

  Hereinafter, the present embodiment will be specifically described with reference to examples, but the present embodiment is not limited to these examples.

[Examples 1 to 7 and Comparative Example 1]
Examples 1 to 7 and Comparative Examples were prepared by blending the various components shown below in the ratios (parts by mass) shown in Table 1 and kneading the rolls at a kneading temperature of 80 ° C. and a kneading time of 15 minutes. An epoxy resin composition of No. 1 was prepared.

The components used for preparing the epoxy resin composition are as follows.
Epoxy resin: diphenylmethane type epoxy resin having an epoxy equivalent of 192 g / eq and a melting point of 79 ° C. (trade name: YSLV-80XY, manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.)
-Curing agent (phenol resin): triphenylmethane type phenol resin having a hydroxyl equivalent of 102 g / eq and a softening point of 70 ° C (trade name: HE910-09, manufactured by Air Water Inc.)
・ Curing accelerator: Triphenylphosphine ・ Release agent: Carnauba wax (manufactured by Ceralica NODA)
・ Coupling agent: Epoxysilane (γ-glycidoxypropyltrimethoxysilane)
Colorant: carbon black (manufactured by Mitsubishi Chemical Corporation, trade name MA-100)
-Inorganic filler: alumina filler with an average particle size of 10 µm (Denka Corporation, trade name: DOW series mixed)

[Evaluation of thermal conductivity of epoxy resin composition]
The thermal conductivity of the epoxy resin compositions obtained in Examples 1 to 7 and Comparative Example 1 was evaluated by the following test methods. Table 2 shows the evaluation results. The molding of the epoxy resin composition for measuring thermal conductivity was performed using a vacuum hand press molding machine under the conditions of a mold temperature of 180 ° C., a molding pressure of 6.9 MPa, and a curing time of 10 minutes. Post-curing was performed at 175 ° C. for 6 hours.

Next, the thermal diffusivity in the thickness direction of the cured product (1 cm × 1 cm) molded by the above method was measured by a laser flash method. More specifically, the thermal diffusivity was measured using a xenon flash analyzer (apparatus: LFA447 nanoflash, manufactured by NETZSCH). The pulse light irradiation was performed under the conditions of a pulse width of 0.1 ms and an applied voltage of 247 V. The measurement was performed at an ambient temperature of 25 ° C. ± 1 ° C. Next, the value of the thermal conductivity was obtained by multiplying the specific heat and the density by the thermal diffusivity using the following equation (1). The specific heat of the cured product was calculated from DSC measurement data by a method according to JIS K 7123: 2012, and the density was measured with an electronic hydrometer (Alpha Mirage Co., Ltd., SD-200L).
λ = α · Cp · ρ Equation (1)
In the formula (I), λ is the thermal conductivity (W / (m · K)), α is the thermal diffusivity (m ² / s), Cp is the specific heat (J / (kg · K)), and ρ is the density ( d: kg / m ³ ).

  The thermal conductivity of Comparative Example 1 was taken as a reference, and A having improved thermal conductivity was designated as A, and B having almost the same thermal conductivity was designated as B.

[Evaluation of fluidity of epoxy resin composition]
The fluidity of the epoxy resin compositions obtained in Examples 1 to 7 and Comparative Example 1 was evaluated by the following test methods. Table 2 shows the evaluation results. The epoxy resin composition was molded using a transfer molding machine under the conditions of a mold temperature of 180 ° C., a molding pressure of 6.9 MPa, and a curing time of 90 seconds. Post-curing was performed at 175 ° C. for 6 hours.

  The spiral flow test was performed by molding an epoxy resin composition under the above conditions using a mold for measuring spiral flow according to EMMI-1-66, and measuring the flow distance (cm). With the flow distance of Comparative Example 1 as a standard, A with improved fluidity was designated as A, and B with slightly improved fluidity was designated as B.

[Evaluation of reliability of epoxy resin composition]
The reliability (insulation reliability) of the epoxy resin compositions obtained in Examples 1 to 7 and Comparative Example 1 was evaluated by a partial discharge test shown below.
First, copper foil was provided on both sides of an epoxy resin cured product obtained from an epoxy resin composition by molding using the above-described transfer molding machine. A circular pattern having a diameter of 20 mm was formed on one side of a cured epoxy resin having a double-sided copper foil (sample size 50 mm × 50 mm, resin thickness 0.2 mm, copper foil thickness 0.1 mm) by etching. Next, the epoxy resin composition was dried on a hot plate at 120 ° C. for 1 hour to obtain an electrode-formed sample, which was used in the following partial discharge test. The surface of the electrode forming sample on which the pattern was formed was defined as the front side.

  Next, a stainless steel container was filled with insulating oil (Fluorinert FC-40 manufactured by 3M), and the electrode measurement sample was immersed. Then, an aluminum weight was placed on the sample front electrode to fix the sample. The stainless steel container was installed together with the stainless steel container in a measurement box of a partial discharge test device (DAC-6032C, Soken Electric Co., Ltd.), and the front electrode was connected to the high voltage side, and the stainless steel container was connected to the ground terminal. The frequency was set to 60 Hz, and the step-up / step-down speed was set to 0.1 kV step / second, and the discharge charge amount was measured. A voltage at which a discharge charge of 2 pC or more was detected was defined as a partial discharge start voltage. A was used when the voltage was equal to or higher than Comparative Example 1, and B was used when the voltage was lowered. When the voltage is reduced, it means that the reliability (insulation reliability) is reduced.

As shown in Table 2, Examples 1 to 7 in which the epoxy resin composition contained an organic solvent had better fluidity evaluated by spiral flow as compared with Comparative Example 1 containing no organic solvent, and in particular, In Examples 1 to 5, the thermal conductivity (thermal conductivity after curing) and the fluidity evaluated by spiral flow were better than Comparative Example 1. In Examples 1 to 6, the reliability evaluated by the partial discharge test was equal to or higher than Comparative Example 1.
In Examples 1 to 5, in particular, the lowering of the viscosity improves the dispersibility of the epoxy resin, improves the curability (reaction rate), and promotes the molecular motion of the epoxy resin to improve the orientation. It is presumed that this contributes to the improvement in conductivity.

  All documents, patent applications, and technical standards mentioned herein are to the same extent as if each individual document, patent application, and technical standard were specifically and individually stated to be incorporated by reference. Incorporated herein by reference.

Claims (8)

  An epoxy resin composition containing an epoxy resin, a curing agent, an inorganic filler, and an organic solvent having a boiling point of 50C to 100C.   The epoxy resin composition according to claim 1, wherein the content of the organic solvent is from 0.1% by mass to 10% by mass.   The epoxy resin composition according to claim 1, wherein the content of the inorganic filler is 55% by mass to 95% by mass.   The epoxy resin composition according to any one of claims 1 to 3, further comprising a coupling agent.   The epoxy resin composition according to claim 4, wherein the content of the coupling agent is 0.05% by mass to 5.0% by mass.   An epoxy resin composition which is tablet-shaped and has a content of an organic solvent having a boiling point of 50 ° C to 100 ° C of 0.3% by mass to 3.0% by mass.   An epoxy resin cured product obtained by curing the epoxy resin composition according to any one of claims 1 to 6.   An electronic component device comprising: an element; and the epoxy resin cured product according to claim 7, which seals the element.