Method for producing thermosetting resin composition, thermosetting resin composition, and electronic component device

Abstract

To provide a method for producing a novel curable resin composition capable of suppressing mixing of metal foreign matter, a thermosetting resin composition obtained by the production method, and an electronic component device including an element sealed with the thermosetting resin composition.SOLUTION: A method for producing a thermosetting resin composition, the method comprising: primary kneading of kneading a mixture of a thermosetting resin and an inorganic filler with a kneading extruder; and secondary kneading of adding a curing agent after the primary kneading and further kneading the mixture with the kneading extruder.SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] Thermosetting resin compositions used for applications such as encapsulation of semiconductor elements are generally produced by premixing components such as a thermosetting resin, a curing agent, an inorganic filler, and additives in a mixer or the like, followed by melt-kneading. After cooling, the melt-kneaded composition is subjected to treatments such as pulverization and tableting depending on the application.

[0003] In the production of a thermosetting resin composition, metal contamination occurs in each production step, such as premixing, melt-kneading, and pulverization. For example, in the premixing using a mixer or the like, metals originating from the mixer are mixed in. It is preferable that the amount of such metal foreign matter mixed in the thermosetting resin composition be as small as possible.

[0004] For example, in the field of semiconductor packaging, there has been a rapid increase in demand for small packages, and semiconductor packages that can accommodate a large number of connection terminals despite their small size are required. As semiconductor packages become smaller and more powerful, the pitch of the internal metal wires has also become narrower, with the latest packages having metal wire pitches of just under 100 μm. In this case, if relatively large metal foreign particles are mixed into the thermosetting resin composition used to encapsulate semiconductor elements, they may become trapped between the narrowly-pitched metal wires, causing a short circuit.

[0005] In order to reduce the inclusion of conductive foreign matter, for example, a method of removing the conductive foreign matter using a magnetic separator has been adopted (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-294677 Summary of the Invention [Problem to be solved by the invention]

[0007] On the other hand, there is a need for the development of a new method for producing a thermosetting resin composition that can reduce the inclusion of metallic foreign matter through a simple process. In view of this situation, an object of the present disclosure is to provide a new method for producing a curable resin composition that can suppress the inclusion of metallic foreign matter, a thermosetting resin composition obtained by the method, and an electronic component device including an element encapsulated with the thermosetting resin composition. [Means for solving the problem]

[0008] Means for solving the above problems include the following aspects. <1> a primary mixing step in which a mixture of a thermosetting resin and an inorganic filler is mixed in a mixing extruder; After the primary kneading, a curing agent is added and the mixture is further kneaded in the kneading extruder. A method for producing a thermosetting resin composition, comprising: <2> Further comprising adding a hardening accelerator in the secondary kneading. <1> A method for producing the thermosetting resin composition according to claim 1. <3> In the secondary kneading, a mixture of the curing agent and the curing accelerator is added. <2> A method for producing the thermosetting resin composition according to claim 1. <4> A method for producing a thermosetting resin composition in which the content of metals having a particle size of 45 μm or more is 0.000042 mass% or less relative to the total mass of the thermosetting resin composition. <1> ~ <3> 10. A method for producing the thermosetting resin composition according to claim 9. <5> The kneading extruder A first kneading section; A second kneading section disposed downstream in the extrusion direction of the first kneading section; A main material inlet connected to the first kneading section; At least two side feeders including a first side feeder connected to the first kneading section and a second side feeder connected to the second kneading section; A twin-screw kneading extruder having <1> ~ <4> 10. A method for producing the thermosetting resin composition according to claim 9. <6> the primary kneading includes feeding the inorganic filler through the main material feeding port, feeding the thermosetting resin through the first side feeder, and kneading in the first kneading section; The secondary kneading includes adding the curing agent from the second side feeder and kneading in the second kneading section. <5> A method for producing the thermosetting resin composition according to claim 1. <7> The thermosetting resin and the inorganic filler are not premixed before being introduced into the kneading extruder. <1> ~ <6> 10. A method for producing the thermosetting resin composition according to claim 9. <8> <1> ~ <7> 1. A thermosetting resin composition obtained by the production method according to any one of claims 1 to 9. <9> <1> ~ <7> 1. An electronic component device comprising an element encapsulated with a thermosetting resin composition obtained by the manufacturing method according to any one of claims 1 to 9. [Effects of the Invention]

[0009] According to the present disclosure, there are provided a novel method for producing a curable resin composition that can suppress the inclusion of metallic foreign matter, a thermosetting resin composition obtained by the method, and an electronic component device including an element encapsulated with the thermosetting resin composition. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic cross-sectional view of a kneading extruder used in one embodiment of the production method of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, components (including element steps, etc.) are not essential unless otherwise specified. The same applies to numerical values ​​and their ranges, and do not limit the present invention.

[0012] In the present disclosure, the term "process" includes not only a process that is independent of other processes, but also a process that cannot be clearly distinguished from other processes as long as the purpose of the process is achieved. In the present disclosure, numerical ranges indicated using "to" include the numerical values ​​before and after "to" as the minimum and maximum values, respectively. In the numerical ranges described in stages in this disclosure, the upper or lower limit value described in one numerical range may be replaced with the upper or lower limit value of another numerical range described in stages. Furthermore, in the numerical ranges described in this disclosure, the upper or lower limit value of that numerical range may be replaced with a value shown in the examples. In the present disclosure, each component may contain multiple substances corresponding to the component. When multiple substances corresponding to each component are present in the composition, the content or amount of each component means the total content or amount of the multiple substances present in the composition, unless otherwise specified. In the present disclosure, multiple types of particles corresponding to each component may be contained. When multiple types of particles corresponding to each component are present in the composition, the particle size of each component means the value for a mixture of the multiple types of particles present in the composition, unless otherwise specified. In this disclosure, solid, solid, liquid, and liquid refer to the state at 25°C. When embodiments of the present disclosure are described with reference to the drawings, the configuration of the embodiment is not limited to the configuration shown in the drawings. Furthermore, the sizes of the components in each drawing are conceptual, and the relative size relationships between the components are not limited to these.

[0013] <Method for producing thermosetting resin composition> The method for producing a thermosetting resin composition of the present disclosure (hereinafter also referred to as the production method of the present disclosure) includes a primary kneading step in which a mixture of a thermosetting resin and an inorganic filler is kneaded in a kneader extruder, and a secondary kneading step in which a curing agent is added after the primary kneading and further kneading is performed in the kneader extruder. According to the production method of the present disclosure, the inorganic filler and the thermosetting resin are first kneaded, and then the curing agent is added and kneaded sequentially, thereby ensuring favorable dispersion of each component without uneven distribution. As a result, it has been found that good physical properties can be ensured when the thermosetting resin composition is cured. Furthermore, in the production of a thermosetting resin composition, it has been common to premix the components in a mixer before kneading and then charge the mixture into a kneader to prevent uneven distribution of each component. However, according to the method of the present disclosure, it is possible to omit the premixing step, and it has been found that this method can prevent the inclusion of metallic foreign matter due to premixing.

[0014] [Primary kneading] In the primary kneading, a mixture of a thermosetting resin and an inorganic filler is kneaded in a kneading extruder. At this time, a coupling agent and other additives may be further mixed as needed. In the primary kneading, a portion of the curing agent added in the secondary kneading may be mixed, as long as the effect on the dispersibility of the resulting thermosetting resin composition is not a practical problem. In the present disclosure, when the curing agent is added in multiple batches, for convenience, the kneading after adding the majority of the total curing agent to be added, i.e., 50% by mass or more of the curing agent, is referred to as the secondary kneading. When a portion of the curing agent is mixed in the primary kneading, the amount mixed is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 10% by mass or less of the total curing agent to be added. From the viewpoint of simplifying the manufacturing process, the thermosetting resin and the inorganic filler are preferably kneaded in the primary kneading without adding a curing agent.

[0015] An example of a kneading method for the primary kneading is a method of melt-kneading using a kneading extruder preheated to a desired temperature. The specific embodiment of the kneading extruder is not particularly limited, and it may have one or more component inlets. In one embodiment, the kneading extruder can extrude the mixture in a predetermined direction using a motor while kneading each component. For example, by adding additional components through an inlet (side feeder) provided separately from the inlet for the main material, the components can be sequentially added and kneaded. This makes it possible to improve the dispersibility of each component. Examples of kneading extruders include screw extruders such as single-screw kneading extruders, twin-screw kneading extruders, and triple-screw kneading extruders. Among these, twin-screw kneading extruders are preferred from the viewpoint of component dispersibility and distribution. In this disclosure, for convenience, terms such as "main material inlet" and "inlet (side feeder) provided separately from the main material inlet" may be used, but there are no particular limitations on the types or amounts of components added through these inlets. In other words, the main material refers to any component in any amount among the components contained in the thermosetting resin composition.

[0016] The temperature of the primary kneading is preferably adjusted according to the melting temperature of the resin material used. The temperature of the primary kneading is preferably higher than the melting point or softening point of the thermosetting resin (when multiple types of thermosetting resins are used in combination, the thermosetting resin with the highest melting point or softening point). For example, the temperature of the primary kneading is preferably 1°C to 90°C higher than the melting point or softening point of the thermosetting resin (when multiple types of thermosetting resins are used in combination, the thermosetting resin with the highest melting point or softening point), more preferably 1°C to 70°C higher, and even more preferably 1°C to 50°C higher. By kneading at such a temperature, the thermosetting resin can be melted and fluidity can be maintained, thereby enabling good stirring and mixing.

[0017] In one embodiment, the temperature of the primary kneading may be 70°C or higher, 80°C or higher, 90°C or higher, 100°C or higher, 110°C or higher, or 120°C or higher. From the viewpoint of suppressing an increase in viscosity, the temperature of the primary kneading may be 200°C or lower. From this viewpoint, the temperature of the primary kneading may be 70°C to 200°C, 80°C to 200°C, 90°C to 200°C, 100°C to 200°C, 110°C to 200°C, or 120°C to 200°C.

[0018] [Secondary kneading] In the secondary kneading, a curing agent is added after the primary kneading, and further kneading is performed in the kneading extruder. Since the curing agent is added sequentially following the primary kneading, uneven distribution of each component tends to be suppressed and kneading properties can be improved. The method of adding the curing agent is not particularly limited as long as it allows for post-addition of the curing agent. For example, there is a method in which the curing agent is added to the mixture that has undergone the primary kneading as described above through the inlet into which the components for the primary kneading were added, or a method in which the curing agent is added through an inlet (side feeder) provided separately from the inlet into which the components for the primary kneading were added.

[0019] The manufacturing method of the present disclosure may further include adding a curing accelerator during secondary kneading. The method of adding the curing accelerator is not particularly limited as long as it allows for post-addition of the curing accelerator. For example, the curing agent may be added to the mixture that has undergone primary kneading as described above through an inlet where the components for primary kneading were added, or through an inlet (side feeder) provided separately from the inlet for the components for primary kneading. Adding the curing accelerator during secondary kneading can suppress thickening during primary kneading compared to adding the curing accelerator during primary kneading. This tends to ensure sufficient kneadability during primary kneading. It is also possible to suppress viscosity increase during primary kneading by adding a portion of the curing accelerator during primary kneading and then adding the remaining amount, preferably a majority of the total curing accelerator by mass, during secondary kneading. Adding the entire amount of the curing accelerator during secondary kneading is preferred.

[0020] A mixture of a curing agent and a curing accelerator may be added in the secondary kneading. Even if the amount of the curing accelerator added is small relative to the resin component, for example, about 1 to 30 parts by mass per 100 parts by mass of the resin component (i.e., the total of the thermosetting resin and the curing agent) as described below, adding the curing accelerator as a mixture with the curing agent in the secondary kneading can prevent uneven distribution of the curing accelerator, which tends to ensure good physical properties when the cured product is obtained.

[0021] In a preferred embodiment, the kneading extruder may be a twin-screw kneading extruder having a first kneading section, a second kneading section disposed downstream of the first kneading section in the extrusion direction, a main material inlet connected to the first kneading section, and at least two side feeders including a first side feeder connected to the first kneading section and a second side feeder connected to the second kneading section.

[0022] In a preferred embodiment, the primary mixing may include adding the inorganic filler through the main material inlet, adding the thermosetting resin through the first side feeder, and mixing in the first kneading section, and the secondary mixing may include adding the curing agent through the second side feeder and mixing in the second kneading section. In this embodiment, the mixing is performed, for example, as follows: The inorganic filler is added through the main material inlet, the thermosetting resin is added through the first side feeder, and the primary mixing is performed in the first kneading section, kneading the mixture of the thermosetting resin and the inorganic filler. In this case, for example, the inorganic filler added through the main material inlet may be added in the direction of gravity, and the thermosetting resin and the curing agent added through the first and second side feeders may be added while applying a forcing force using a screw or the like. The mixture from the primary mixing is extruded by a motor and moves to the second kneading section downstream in the extrusion direction. A curing agent (a mixture of a curing agent and a curing accelerator, if necessary) is added from the second side feeder, and secondary kneading is carried out in the second kneading section.

[0023] In one embodiment, cooling may be performed after the primary kneading when transitioning to the secondary kneading. The cooling process is particularly useful when it is preferable to perform the primary kneading at a higher temperature than the secondary kneading, that is, when it is preferable to perform the secondary kneading at a lower temperature than the primary kneading. The cooling process is useful when a thermosetting resin with a relatively high melting point or softening point, for example, a thermosetting resin with a melting point or softening point of 90°C or higher, 100°C or higher, 110°C or higher, or 120°C or higher, is melted in the primary kneading.

[0024] The temperature of the secondary kneading is not particularly limited, and may be 110°C to 100°C, 100°C to 90°C, or 90°C to 80°C from the viewpoints of kneading properties, suppressing thickening, and the like.

[0025] [Other steps] The manufacturing method of the present disclosure may include other steps at any timing in addition to the primary kneading and secondary kneading. For example, any component other than the thermosetting resin, inorganic filler, and curing agent may be added simultaneously with or at a different time from one or more of the thermosetting resin, inorganic filler, and curing agent, and kneaded. The composition obtained through the primary kneading and secondary kneading may be cooled and pulverized to obtain a solid thermosetting resin composition. The obtained solid thermosetting resin composition may be tableted using a tablet press.

[0026] Conventionally, in the production of a thermosetting resin composition, in order to sufficiently knead each component, it has been common to perform premixing in which each component, such as a thermosetting resin and an inorganic filler, is mixed in advance in a mixer or the like before adding the components to a kneader. On the other hand, according to the production method of a thermosetting resin composition disclosed herein, sufficient kneadability tends to be ensured even without premixing the thermosetting resin and the inorganic filler before feeding the thermosetting resin and the inorganic filler into a kneading extruder. This makes it possible to suppress the introduction of metallic foreign matter that occurs during premixing.

[0027] A schematic cross-sectional view of a kneading extruder used in one embodiment is shown in Figure 1. The kneading extruder 10 includes a first kneading section A, a second kneading section B disposed downstream of the first kneading section A in the extrusion direction, a main material inlet 1 connected to the first kneading section A, a first side feeder 2 connected to the first kneading section A, and a second side feeder 3 connected to the second kneading section B. In Figure 1, the arrow indicates the extrusion direction of the composition. Specific examples of the kneading method are as described above.

[0028] Hereinafter, each component used in the production method of the present disclosure, i.e., each component contained in the thermosetting resin composition, will be described.

[0029] <Thermosetting resin> The type of thermosetting resin is not particularly limited, and examples include epoxy resins, phenolic resins, urea resins, melamine resins, urethane resins, silicone resins, and unsaturated polyester resins. In the present disclosure, "thermosetting resins" include those that exhibit both thermoplastic and thermosetting properties, such as acrylic resins containing epoxy groups. Thermosetting resins may be solid or liquid at room temperature and normal pressure (e.g., 25°C and atmospheric pressure), and are preferably solid. Thermosetting resins may be used alone or in combination of two or more.

[0030] The thermosetting resin preferably includes an epoxy resin. Specific examples of epoxy resins include novolac epoxy resins (phenol novolac epoxy resins, orthocresol novolac epoxy resins, etc.) obtained by epoxidizing novolac resins obtained by condensing or co-condensing, under an acid catalyst, at least one phenolic compound selected from the group consisting of phenolic compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, etc., and naphthol compounds such as α-naphthol, β-naphthol, dihydroxynaphthalene, etc., with an aliphatic aldehyde compound such as formaldehyde, acetaldehyde, propionaldehyde, etc.; triphenylmethane epoxy resins obtained by epoxidizing triphenylmethane phenolic resins obtained by condensing or co-condensing, under an acid catalyst, the above-mentioned phenolic compound with an aromatic aldehyde compound such as benzaldehyde, salicylaldehyde, etc.; and novolac resins obtained by co-condensing, under an acid catalyst, the above-mentioned phenolic compound and naphthol compound with an aldehyde compound. Copolymerized epoxy resins obtained by epoxidizing a fatty acid; diphenylmethane-type epoxy resins, which are diglycidyl ethers of bisphenol A, bisphenol F, etc.; biphenyl-type epoxy resins, which are diglycidyl ethers of alkyl-substituted or unsubstituted biphenols; stilbene-type epoxy resins, which are diglycidyl ethers of stilbene-based phenolic compounds; sulfur-containing epoxy resins, which are diglycidyl ethers of bisphenol S, etc.; epoxy resins, which are glycidyl ethers of alcohols such as butanediol, polyethylene glycol, and polypropylene glycol; glycidyl ester-type epoxy resins, which are glycidyl esters of polycarboxylic acids such as phthalic acid, isophthalic acid, and tetrahydrophthalic acid; glycidylamine-type epoxy resins, in which the active hydrogen bonded to the nitrogen atom of aniline, diaminodiphenylmethane, isocyanuric acid, etc. is substituted with a glycidyl group; and dicyclopentadiene-type epoxy resins, which are epoxidized co-condensation resins of dicyclopentadiene and phenolic compounds.Alicyclic epoxy resins such as vinylcyclohexene diepoxide, 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and 2-(3,4-epoxy)cyclohexyl-5,5-spiro(3,4-epoxy)cyclohexane-m-dioxane, which are produced by epoxidizing the olefin bonds in the molecule; paraxylylene-modified epoxy resins, which are glycidyl ethers of paraxylylene-modified phenolic resins; metaxylylene-modified epoxy resins, which are glycidyl ethers of metaxylylene-modified phenolic resins; terpene-modified epoxy resins, which are glycidyl ethers of terpene-modified phenolic resins; and dicyclopentadiene-modified phenolic resins, which are glycidyl ethers of dicyclopentadiene-modified phenolic resins. Examples of suitable epoxy resins include pentadiene-modified epoxy resins, cyclopentadiene-modified epoxy resins which are glycidyl ethers of cyclopentadiene-modified phenolic resins, polycyclic aromatic ring-modified epoxy resins which are glycidyl ethers of polycyclic aromatic ring-modified phenolic resins, naphthalene-type epoxy resins which are glycidyl ethers of naphthalene ring-containing phenolic resins, halogenated phenol novolac-type epoxy resins, hydroquinone-type epoxy resins, trimethylolpropane-type epoxy resins, linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid, and aralkyl-type epoxy resins obtained by epoxidizing aralkyl-type phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins. Further examples of suitable epoxy resins include epoxidized silicone resins and epoxidized acrylic resins. These epoxy resins may be used alone or in combination of two or more.

[0031] When the thermosetting resin is an epoxy resin, the epoxy equivalent (molecular weight / number of epoxy groups) of the epoxy resin is not particularly limited. From the viewpoint of the balance of various properties such as moldability, reflow resistance, and electrical reliability, it is preferably 100 g / eq to 1000 g / eq, and more preferably 150 g / eq to 500 g / eq. The epoxy equivalent of the epoxy resin is a value measured by a method in accordance with JIS K 7236:2009.

[0032] When the thermosetting resin is solid at 25° C., the melting point or softening point of the thermosetting resin is not particularly limited. From the viewpoint of blocking resistance, the melting point or softening point of the thermosetting resin is preferably 40° C. or higher, and more preferably 50° C. or higher. From the viewpoint of suppressing thickening due to kneading, the melting point or softening point of the thermosetting resin is preferably 150° C. or lower, more preferably 140° C. or lower, and even more preferably 130° C. or lower.

[0033] From the viewpoints of strength, fluidity, heat resistance, moldability, etc., the content of the thermosetting resin is preferably 0.5% by mass to 50% by mass, more preferably 2% by mass to 30% by mass, and even more preferably 2% by mass to 20% by mass, relative to the total mass of the thermosetting resin composition.

[0034] <Inorganic filler> The material of the inorganic filler is not particularly limited. Specific examples of the inorganic filler include silica such as fused silica and crystalline silica, glass, alumina, calcium carbonate, zirconium silicate, calcium silicate, silicon nitride, aluminum nitride, boron nitride, magnesium oxide, silicon carbide, beryllia, zirconia, zircon, fosterite, steatite, spinel, mullite, titania, talc, clay, and mica. Inorganic fillers with flame retardant properties may also be used. Examples of inorganic fillers with flame retardant properties include aluminum hydroxide, magnesium hydroxide, composite metal hydroxides such as composite hydroxides of magnesium and zinc, and zinc borate. Among inorganic fillers, silica such as fused silica is preferred from the viewpoint of reducing the linear expansion coefficient, and alumina is preferred from the viewpoint of high thermal conductivity.

[0035] The shape of the inorganic filler is not particularly limited, but from the viewpoints of filling properties and mold wear, a spherical shape is preferred.

[0036] The inorganic filler may be used alone or in combination of two or more. The term "use of two or more inorganic fillers" refers to, for example, the use of two or more inorganic fillers having the same components but different average particle sizes, the use of two or more inorganic fillers having the same average particle size but different components, and the use of two or more inorganic fillers having different average particle sizes and types.

[0037] The content of the inorganic filler is not particularly limited. From the viewpoint of further improving the properties of the cured product of the thermosetting resin composition, such as the thermal expansion coefficient, thermal conductivity, and elastic modulus, the content of the inorganic filler is preferably 30% by volume or more of the entire thermosetting resin composition, more preferably 40% by volume or more, even more preferably 50% by volume or more, particularly preferably 60% by volume or more, and extremely preferably 70% by volume or more. From the viewpoint of improving the fluidity and reducing the viscosity of the thermosetting resin composition, the content of the inorganic filler is preferably 99% by volume or less of the entire thermosetting resin composition, preferably 98% by volume or less, and more preferably 97% by volume or less. Furthermore, for example, when the thermosetting resin composition is used for compression molding, the content of the inorganic filler may be 70 to 99 volume % of the entire thermosetting resin composition, 80 to 99 volume %, 83 to 99 volume %, or 85 to 99 volume %.

[0038] The content of inorganic filler in a cured product of a thermosetting resin composition can be measured as follows. First, the total mass of the cured product is measured, and the cured product is baked at 400°C for 2 hours and then at 700°C for 3 hours to evaporate the resin components, etc., and the mass of the remaining inorganic filler is measured. The volumes are calculated from the obtained masses and their specific gravities, and the ratio of the volume of the inorganic filler to the total volume of the cured product is determined as the inorganic filler content.

[0039] The manufacturing method of the present disclosure tends to improve the kneadability of the mixture of components, and therefore, it is believed that the manufacturing method of the present disclosure makes it possible to increase the inorganic filler content in compositions in which the content of inorganic filler could not be increased by conventional methods due to concerns about the effects of increased viscosity, such as wire sweep in semiconductor packages.

[0040] When the inorganic filler is particulate, its average particle diameter is not particularly limited. For example, the volume average particle diameter of the entire inorganic filler is preferably 80 μm or less, and may be 50 μm or less, 40 μm or less, 30 μm or less, or 20 μm or less. Furthermore, the volume average particle diameter of the entire inorganic filler is preferably 0.1 μm or more, more preferably 0.2 μm or more, and even more preferably 0.3 μm or more. When the volume average particle diameter of the inorganic filler is 0.1 μm or more, the increase in viscosity of the thermosetting resin composition tends to be further suppressed. When the volume average particle diameter of the inorganic filler is 80 μm or less, the filling ability into narrow gaps tends to be further improved. The volume average particle diameter of the inorganic filler can be measured as the particle diameter (D50) at which the cumulative amount from the small diameter side reaches 50% in the volume-based particle size distribution measured using a laser scattering diffraction particle size distribution analyzer.

[0041] <Curing agent> The curing agent is not particularly limited as long as it is a compound that undergoes a curing reaction with the thermosetting resin that has been subjected to primary kneading, and may itself be a thermosetting resin. For example, curing agents that can be used in combination with epoxy resins include phenolic curing agents, amine curing agents, acid anhydride curing agents, polymercaptan curing agents, polyaminoamide curing agents, isocyanate curing agents, and blocked isocyanate curing agents. One type of curing agent may be used alone, or two or more types may be used in combination. From the viewpoint of improving heat resistance, the curing agent is preferably a compound having a phenolic hydroxyl group in the molecule (also referred to as a phenolic curing agent). The curing agent may be solid or liquid at room temperature and normal pressure (e.g., 25°C, atmospheric pressure), and is preferably solid.

[0042] Specific examples of the phenolic curing agent include polyhydric phenolic compounds such as resorcinol, catechol, bisphenol A, bisphenol F, and substituted or unsubstituted biphenols; novolak-type phenolic resins obtained by condensing or co-condensing at least one phenolic compound selected from the group consisting of phenolic compounds such as phenol, cresol, xylenol, resorcinol, catechol, bisphenol A, bisphenol F, phenylphenol, and aminophenol, and naphthol compounds such as α-naphthol, β-naphthol, and dihydroxynaphthalene, with an aldehyde compound such as formaldehyde, acetaldehyde, propionaldehyde, benzaldehyde, and salicylaldehyde, under an acidic catalyst; and copolymers of the above phenolic compounds with dimethoxyparaxylene, bis(methoxymethyl)biphenol, and the like. Examples of suitable phenolic curing agents include aralkyl phenolic resins such as phenol aralkyl resins and naphthol aralkyl resins synthesized from phenyl or the like; paraxylylene and / or metaxylylene-modified phenolic resins; melamine-modified phenolic resins; terpene-modified phenolic resins; dicyclopentadiene-type phenolic resins and dicyclopentadiene-type naphthol resins synthesized by copolymerization of the above phenolic compounds with dicyclopentadiene; cyclopentadiene-modified phenolic resins; polycyclic aromatic ring-modified phenolic resins; biphenyl-type phenolic resins; triphenylmethane-type phenolic resins obtained by condensation or co-condensation of the above phenolic compounds with aromatic aldehyde compounds such as benzaldehyde or salicylaldehyde under an acidic catalyst; and phenolic resins obtained by copolymerization of two or more of these. The phenolic curing agents may be used singly or in combination of two or more.

[0043] The functional group equivalent of the curing agent (hydroxyl group equivalent for phenolic curing agents, active hydrogen equivalent for amine curing agents) is not particularly limited. From the viewpoint of the balance of various properties such as moldability, reflow resistance, and electrical reliability, the functional group equivalent of the curing agent is preferably 70 g / eq to 1000 g / eq, and more preferably 80 g / eq to 500 g / eq.

[0044] The hydroxyl equivalent weight for phenolic curing agents is a value calculated based on the hydroxyl value measured in accordance with JIS K0070:1992, and the active hydrogen equivalent weight for amine curing agents is a value calculated based on the amine value measured in accordance with JIS K7237:1995.

[0045] When the curing agent is solid, its softening point or melting point is not particularly limited. The softening point or melting point of the curing agent is preferably 40°C to 180°C from the viewpoint of moldability and reflow resistance when the thermosetting resin composition is used as an encapsulant, and more preferably 50°C to 130°C from the viewpoint of handleability during production of the thermosetting resin composition.

[0046] The melting point or softening point of the curing agent is a value measured in the same manner as the melting point or softening point of the epoxy resin.

[0047] The equivalent ratio of the thermosetting resin to the curing agent, i.e., the ratio of the number of functional groups in the curing agent to the number of functional groups in the thermosetting resin (number of functional groups in the curing agent / number of functional groups in the thermosetting resin), is not particularly limited. In order to minimize the amount of unreacted components, the equivalent ratio of the thermosetting resin to the curing agent is preferably set in the range of 0.5 to 2.0, more preferably in the range of 0.6 to 1.3. From the viewpoint of moldability, the equivalent ratio of the thermosetting resin to the curing agent is more preferably set in the range of 0.8 to 1.2.

[0048] <Curing accelerator> The type of curing accelerator is not particularly limited, and examples thereof include diazabicycloalkenes such as 1,5-diazabicyclo[4.3.0]nonene-5 (DBN) and 1,8-diazabicyclo[5.4.0]undecene-7 (DBU), cyclic amidine compounds such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, and 2-heptadecylimidazole; derivatives of the cyclic amidine compounds; phenol novolac salts of the cyclic amidine compounds or their derivatives; and combinations of these compounds with maleic anhydride, quinone compounds such as 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, and phenyl-1,4-benzoquinone. compounds having intramolecular polarization obtained by adding a compound having a π bond, such as diazophenylmethane; cyclic amidinium compounds such as the tetraphenylborate salt of DBU, the tetraphenylborate salt of DBN, the tetraphenylborate salt of 2-ethyl-4-methylimidazole, and the tetraphenylborate salt of N-methylmorpholine; tertiary amine compounds such as pyridine, triethylamine, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, and tris(dimethylaminomethyl)phenol; derivatives of the above tertiary amine compounds; ammonium salt compounds such as tetra-n-butylammonium acetate, tetra-n-butylammonium phosphate, tetraethylammonium acetate, tetra-n-hexylammonium benzoate, and tetrapropylammonium hydroxide;organic phosphines such as primary phosphines such as ethylphosphine and phenylphosphine; secondary phosphines such as dimethylphosphine and diphenylphosphine; and tertiary phosphines such as triphenylphosphine, diphenyl(p-tolyl)phosphine, tris(alkylphenyl)phosphine, tris(alkoxyphenyl)phosphine, tris(alkylalkoxyphenyl)phosphine, tris(dialkylphenyl)phosphine, tris(trialkylphenyl)phosphine, tris(tetraalkylphenyl)phosphine, tris(dialkoxyphenyl)phosphine, tris(trialkoxyphenyl)phosphine, tris(tetraalkoxyphenyl)phosphine, trialkylphosphine, dialkylarylphosphine, alkyldiarylphosphine, trinaphthylphosphine, and tris(benzyl)phosphine; phosphine compounds such as complexes of the above organic phosphines with organoborons; and complexes of the above organic phosphines or the above phosphine compounds with maleic anhydride, 1,4-benzoquinone, 2,5-toluquinone, 1,4-naphthoquinone, 2,3-dimethylbenzoquinone, compounds having intramolecular polarization obtained by adding a compound having a π bond, such as quinone compounds, such as 2,6-dimethylbenzoquinone, 2,3-dimethoxy-5-methyl-1,4-benzoquinone, 2,3-dimethoxy-1,4-benzoquinone, phenyl-1,4-benzoquinone, and anthraquinone, or diazophenylmethane; compounds having intramolecular polarization obtained by adding the above organic phosphines or the above phosphine compounds with 4-bromophenol, 3-bromophenol, 2-bromophenol, 4-chlorophenol, 3-chlorophenol, 2-chlorophenol, and 4-iodophenol; compounds with intramolecular polarization obtained by reacting halogenated phenol compounds such as phenol, 3-iodophenol, 2-iodophenol, 4-bromo-2-methylphenol, 4-bromo-3-methylphenol, 4-bromo-2,6-dimethylphenol, 4-bromo-3,5-dimethylphenol, 4-bromo-2,6-di-t-butylphenol, 4-chloro-1-naphthol, 1-bromo-2-naphthol, 6-bromo-2-naphthol, and 4-bromo-4'-hydroxybiphenyl, followed by a dehydrohalogenation step;Examples of the curing accelerator include tetra-substituted phosphonium compounds such as tetraphenylphosphonium, tetraphenylborate salts of tetra-substituted phosphonium such as tetraphenylphosphonium tetra-p-tolylborate, and salts of tetra-substituted phosphonium with phenolic compounds; phosphobetaine compounds; and adducts of phosphonium compounds with silane compounds. One type of curing accelerator may be used alone, or two or more types may be used in combination.

[0049] For example, when an epoxy resin is used as the thermosetting resin, examples of particularly suitable curing accelerators include triphenylphosphine and an adduct of triphenylphosphine and a quinone compound.

[0050] The content of the curing accelerator is preferably 0.1 to 30 parts by mass, and more preferably 1 to 15 parts by mass, per 100 parts by mass of the resin component. When the amount of the curing accelerator is 0.1 part by mass or more per 100 parts by mass of the resin component, good curing tends to occur in a short time. When the amount of the curing accelerator is 30 parts by mass or less per 100 parts by mass of the resin component, the curing speed is not too fast, and good molded products tend to be obtained.

[0051] <Additives> In addition to the above-mentioned components, the thermosetting resin composition may contain various additives such as a coupling agent, an ion exchanger, a release agent, a flame retardant, a colorant, a stress relaxation agent, etc. The thermosetting resin composition may contain various additives commonly used in the technical field, as needed, in addition to the additives exemplified below.

[0052] (coupling agent) The thermosetting resin composition may contain a coupling agent to enhance adhesion between the resin component and the inorganic filler, such as a silane-based compound, a titanium-based compound, an aluminum chelate compound, or an aluminum / zirconium-based compound.

[0053] Examples of silane compounds include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-(2-aminoethyl)aminopropyltrimethoxysilane, 3-(2-aminoethyl)aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-ureidopropyltriethoxysilane, octenyltrimethoxysilane, glycidoxyoctyltrimethoxysilane, and methacryloxyoctyltrimethoxysilane.

[0054] Examples of titanium compounds include isopropyl triisostearoyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, isopropyl tri(N-aminoethyl-aminoethyl) titanate, tetraoctyl bis(ditridecyl phosphite) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(ditridecyl phosphite) titanate, bis(dioctyl pyrophosphate)oxyacetate titanate, bis(dioctyl pyrophosphate)ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl tridodecyl benzenesulfonyl titanate, isopropyl isostearoyl diacryl titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumyl phenyl titanate, and tetraisopropyl bis(dioctyl phosphite) titanate.

[0055] When the thermosetting resin composition contains a coupling agent, the amount of the coupling agent is preferably 0.05 parts by mass to 20 parts by mass, more preferably 0.1 parts by mass to 15 parts by mass, based on 100 parts by mass of the inorganic filler. When the amount of the coupling agent is 0.05 parts by mass or more based on 100 parts by mass of the inorganic filler, the adhesiveness to the metal member tends to be further improved. When the amount of the coupling agent is 20 parts by mass or less based on 100 parts by mass of the inorganic filler, the moldability tends to be improved.

[0056] (Ion exchanger) The thermosetting resin composition may contain an ion exchanger. In particular, when the thermosetting resin composition is used as a molding material for sealing, it is preferable to contain an ion exchanger from the viewpoint of improving the moisture resistance and high-temperature storage characteristics of an electronic component device provided with an element to be sealed. The ion exchanger is not particularly limited, and a conventionally known one can be used. Specifically, hydrotalcite compounds, and hydrous oxides of at least one element selected from the group consisting of magnesium, aluminum, titanium, zirconium, and bismuth can be mentioned. The ion exchanger may be used alone or in combination of two or more. Among them, hydrotalcite represented by the following general formula (A) is preferable.

[0057] Mg Al X (OH)2(CO3) X / 2 ·mH2O ……(A) (0 < X ≦ 0.5, m is a positive number)

[0058] When the thermosetting resin composition contains an ion exchanger, its content is not particularly limited as long as it is sufficient to capture ions such as halogen ions. For example, it is preferably 0.1 parts by mass to 30 parts by mass, more preferably 1 part by mass to 10 parts by mass, based on 100 parts by mass of the resin component.

[0059] (Release agent) The thermosetting resin composition may contain a mold release agent from the viewpoint of obtaining good releasability from the mold during molding. There are no particular limitations on the mold release agent, and conventionally known ones can be used. Specific examples include carnauba wax, higher fatty acids such as montanic acid and stearic acid, higher fatty acid metal salts, ester waxes such as montanic acid esters, and polyolefin waxes such as oxidized polyethylene and non-oxidized polyethylene. One type of mold release agent may be used alone, or two or more types may be used in combination.

[0060] When the thermosetting resin composition contains a release agent, the amount thereof is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the resin component. When the amount of the release agent is 0.01 part by mass or more per 100 parts by mass of the resin component, sufficient release properties tend to be obtained. When the amount is 10 parts by mass or less, better adhesion and curability tend to be obtained.

[0061] (Flame retardant) The thermosetting resin composition may contain a flame retardant. There are no particular limitations on the flame retardant, and conventionally known flame retardants can be used. Specific examples include organic or inorganic compounds containing halogen atoms, antimony atoms, nitrogen atoms, or phosphorus atoms, and metal hydroxides. The flame retardants may be used alone or in combination of two or more.

[0062] When the thermosetting resin composition contains a flame retardant, the amount thereof is not particularly limited as long as it is an amount sufficient to obtain the desired flame retardant effect. For example, the amount is preferably 1 to 30 parts by mass, more preferably 2 to 20 parts by mass, per 100 parts by mass of the resin component.

[0063] (coloring agent) The thermosetting resin composition may further contain a colorant. Examples of the colorant include known colorants such as carbon black, organic dyes, organic pigments, titanium oxide, red lead, and red iron oxide. The content of the colorant can be appropriately selected depending on the purpose, etc. The colorant may be used alone or in combination of two or more.

[0064] (stress reliever) The thermosetting resin composition may contain a stress relaxation agent such as silicone oil or silicone rubber particles. The inclusion of a stress relaxation agent can reduce package warpage and package cracking when the thermosetting resin composition is used as an encapsulant. Examples of the stress relaxation agent include commonly used known stress relaxation agents (flexibilizers). Specific examples include thermoplastic elastomers such as silicone, styrene, olefin, urethane, polyester, polyether, polyamide, and polybutadiene elastomers; rubber particles such as NR (natural rubber), NBR (acrylonitrile-butadiene rubber), acrylic rubber, urethane rubber, and silicone powder; and rubber particles having a core-shell structure such as methyl methacrylate-styrene-butadiene copolymer (MBS), methyl methacrylate-silicone copolymer, and methyl methacrylate-butyl acrylate copolymer. The stress relaxation agents may be used alone or in combination of two or more.

[0065] ≪Thermosetting resin composition≫ The thermosetting resin composition of the present disclosure can be obtained by the manufacturing method of the present disclosure described above. The thermosetting resin composition may be solid or liquid at room temperature and normal pressure (e.g., 25°C and atmospheric pressure), and is preferably solid. When the thermosetting resin composition is solid, its shape is not particularly limited, and examples include powder, granules, tablets, etc.

[0066] [Amount of Metal Impurities in Thermosetting Resin Composition] The lower the content of metal particles with a large particle size, for example, 45 μm or larger, in a thermosetting resin composition, the more preferable. The method for producing a thermosetting resin composition according to the present disclosure tends to prevent the inclusion of relatively large particles, for example, metal particles with a particle size of 45 μm or larger. For example, when a thermosetting resin composition is used for sealing elements in electronic component devices, relatively large foreign particles may become trapped between wires, leading to a decrease in insulation. The method for producing a thermosetting resin composition according to the present disclosure can prevent the inclusion of metal foreign particles, making it suitable for use in applications where the prevention of metal foreign particles is desired. The content of metals having particle sizes of 45 μm or more is preferably 0.000042 mass % or less, more preferably 0.000030 mass % or less, and even more preferably 0.000010 mass % or less, based on the total amount of the thermosetting resin composition.

[0067] The amount of metal impurities is measured using the following method. 300 g of a sample of thermosetting resin composition is melted at a temperature below the onset. A magnet is brought close to the melt, and the metal impurities in the melt are attached to the magnet. The metal impurities attached to the magnet are passed through a sieve with 45 μm openings, and the total mass of the metal impurities remaining on the sieve is measured using a weighing scale. The particle size of the metal impurities refers to the diameter in the case of spherical metal impurities, and the length of the long side in the case of irregular shapes (oval, diamond, etc.).

[0068] [Uses of thermosetting resin composition] The use of the thermosetting resin composition of the present disclosure is not particularly limited, and for example, as exemplified above, it can be used in various packaging techniques as a sealing material for electronic component devices. Furthermore, the thermosetting resin composition of the present disclosure can be used in various applications where it is desirable for the resin composition to have good fluidity and curability, such as resin molded articles for various modules, resin molded articles for motors, resin molded articles for in-vehicle use, and sealing materials for electronic circuit protection materials.

[0069] <Electronic component devices> The electronic component device of the present disclosure includes an element encapsulated with the thermosetting resin composition obtained by the manufacturing method of the present disclosure described above. That is, the electronic component device includes a cured product of the thermosetting resin composition obtained by the manufacturing method of the present disclosure described above.

[0070] Examples of electronic component devices include devices obtained by mounting elements (active elements such as semiconductor chips, transistors, diodes, and thyristors, and passive elements such as capacitors, resistors, and coils) on a support member such as a lead frame, a pre-wired tape carrier, a wiring board, glass, a silicon wafer, or an organic substrate, and then sealing the resulting element portion with a thermosetting resin composition. More specifically, typical resin-sealed ICs such as DIP (Dual Inline Package), PLCC (Plastic Leaded Chip Carrier), QFP (Quad Flat Package), SOP (Small Outline Package), SOJ (Small Outline J-lead package), TSOP (Thin Small Outline Package), and TQFP (Thin Quad Flat Package) have a structure in which an element is fixed on a lead frame, and terminal portions of the element such as bonding pads and lead portions are connected by wire bonding, bumps, or the like, and then sealed by transfer molding or the like using a thermosetting resin composition; TCP (Tape Carrier Package) has a structure in which an element connected to a tape carrier by bumps is sealed with a thermosetting resin composition; and COB (Chip On Board) has a structure in which an element is connected to wiring formed on a support member by wire bonding, flip chip bonding, solder, or the like, and then sealed with a thermosetting resin composition. Examples of suitable thermosetting resin compositions include a BGA (Ball Grid Array), a CSP (Chip Size Package), and an MCP (Multi Chip Package), each of which has a structure in which elements are mounted on the surface of a support member having terminals for connecting a wiring board formed on the back surface thereof, the elements are connected to wiring formed on the support member by bump or wire bonding, and the elements are then sealed with a thermosetting resin composition. Thermosetting resin compositions can also be suitably used in printed wiring boards.

[0071] Examples of methods for encapsulating electronic component devices using a thermosetting resin composition include low-pressure transfer molding, injection molding, and compression molding. [Example]

[0072] The present invention will now be described in more detail with reference to examples, but the present invention is not limited to these examples.

[0073] <Preparation of Thermosetting Resin Composition> First, the following components were prepared.

[0074] (thermosetting resin) Epoxy resin 1: NC-3000 (trade name, Nippon Kayaku Co., Ltd., aralkyl epoxy resin with an epoxy equivalent of 265g / eq to 285g / eq and a softening point of 53°C to 63°C) Epoxy resin 2: jER YX-4000H (trade name, Mitsubishi Chemical Corporation, biphenyl-type epoxy resin with an epoxy equivalent of 180 g / eq to 192 g / eq and a melting point of 105°C) Epoxy resin 3: EPPN501HY (trade name, Nippon Kayaku Co., Ltd., triphenylmethane-type epoxy resin with an epoxy equivalent of 163 g / eq to 175 g / eq and a softening point of 57°C to 63°C)

[0075] (hardening agent) Curing agent: MEHC-7851 (product name, Meiwa Kasei Co., Ltd., biphenylene aralkyl phenolic resin with a hydroxyl group equivalent of 205 g / eq, softening point 60°C to 70°C)

[0076] (Inorganic filler) Inorganic filler: Spherical silica filler with an average particle size of 1.5 μm (no surface treatment)

[0077] (coupling agent) Coupling agent: KBM-573 (trade name, Shin-Etsu Chemical Co., Ltd., N-phenyl-3-aminopropyltrimethoxysilane)

[0078] (curing accelerator) -Curing accelerator: Phosphorus-based curing accelerator

[0079] (Other additives) Release agent: Hoechst wax (Hoechst) Colorant: Carbon black

[0080] The thermosetting resin compositions of Examples 1 to 4 were produced by the following method (referred to as "production method A"). Of the components shown in Table 1, all components except the curing agent and curing accelerator were added to a twin-screw kneader (extruder), and primary kneading was carried out at 120°C for approximately 2 minutes. Then, a mixture of the curing agent and curing accelerator was further added, and secondary kneading was carried out at 80°C for 1 minute. The molten material was cooled with a press roll through which cold water at 10°C was circulated, and the resulting sheet was pulverized into powder, thereby preparing a powdered thermosetting resin composition. The blend amount of each component in Table 1 is expressed in parts by mass unless otherwise specified. In Table 1, "-" indicates that the corresponding component was not blended.

[0081] The thermosetting resin compositions of Comparative Examples 1 to 4 were produced by the following method (referred to as "production method B"). All of the components shown in Table 1 were mixed in a container, and then pulverized and stirred using a high-speed mixer. The mixture was then melt-kneaded for approximately 3 minutes using a twin-screw kneading extruder. The molten material was cooled using a press roll through which 10°C cold water was circulated, and the resulting sheet was pulverized into powder, thereby preparing a powdered thermosetting resin composition.

[0082] <Evaluation of Thermosetting Resin Composition> The prepared thermosetting resin compositions were evaluated by the following tests. The evaluation results are shown in Table 1. Unless otherwise specified, the thermosetting resin compositions were molded using a transfer molding machine under conditions of a mold temperature of 180°C, a molding pressure of 6.9 MPa, and a curing time of 90 seconds. If necessary, post-curing was performed at 175°C for 6 hours.

[0083] [Fluidity (Spiral Flow)] Using a spiral flow measurement mold conforming to EMMI-1-66, the thermosetting resin composition was molded under the above conditions, and the flow distance was determined.

[0084] [Melt Viscosity] The minimum melt viscosity of the thermosetting resin composition at 175°C was measured using a Koka type flow tester (manufactured by Shimadzu Corporation).

[0085] [Gel time] Measurement was carried out on 3 g of the thermosetting resin composition at a temperature of 175° C. using a Curelastometer manufactured by JSR Trading Co., Ltd., and the time until the torque curve rose was taken as the gel time (seconds).

[0086] [Amount of metal foreign matter] 300 g of the thermosetting resin composition was sampled and melted at a temperature equal to or lower than the onset temperature. A magnet was brought close to the molten material, and the metallic foreign matter in the molten material was attached to the magnet. The metallic foreign matter attached to the magnet was sieved on a sieve with 45 μm openings, and the total mass of the metallic foreign matter remaining on the sieve was measured using a weighing scale.

[0087] [Table 1]

[0088] The above evaluation results show that the thermosetting resin compositions of Examples 1 to 4 produced by Production Method A maintained good fluidity, melt viscosity, and gel time, and also had reduced amounts of metallic foreign matter. [Explanation of symbols]

[0089] 1 Main material inlet 2. First Side Feeder 3 Second Side Feeder 10. Kneading extruder A 1st kneading section B Second kneading section

Claims

1. a primary mixing step in which a mixture of a thermosetting resin and an inorganic filler is mixed in a mixing extruder; After the primary kneading, a curing agent is added and the mixture is further kneaded in the kneading extruder. A method for producing a thermosetting resin composition, comprising:

2. The method for producing a thermosetting resin composition according to claim 1 , further comprising adding a curing accelerator in the secondary kneading.

3. The method for producing a thermosetting resin composition according to claim 2 , wherein a mixture of the curing agent and the curing accelerator is added in the secondary kneading.

4. The method for producing a thermosetting resin composition according to any one of claims 1 to 3, wherein the content of metal having a particle size of 45 μm or more is 0.000042 mass% or less relative to the total mass of the thermosetting resin composition.

5. The kneading extruder A first kneading section; a second kneading section disposed downstream of the first kneading section in the extrusion direction; A main material inlet connected to the first kneading section; At least two side feeders including a first side feeder connected to the first kneading section and a second side feeder connected to the second kneading section; The method for producing the thermosetting resin composition according to any one of claims 1 to 4, wherein the extruder is a twin-screw kneading extruder having:

6. the primary kneading includes feeding the inorganic filler through the main material feeding port, feeding the thermosetting resin through the first side feeder, and kneading in the first kneading section; The method for producing a thermosetting resin composition according to claim 5 , wherein the secondary kneading comprises adding the curing agent from the second side feeder and kneading in the second kneading section.

7. 7. The method for producing a thermosetting resin composition according to claim 1, wherein the thermosetting resin and the inorganic filler are not premixed before being introduced into the kneading extruder.

8. A thermosetting resin composition obtained by the method according to any one of claims 1 to 7.

9. An electronic component device comprising an element sealed with the thermosetting resin composition obtained by the manufacturing method according to any one of claims 1 to 7.

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